TECHNICAL FIELD

The present disclosure relates to a method performed by a control device for changing a drill bit in a rock drilling unit, a control device of a rock drilling unit , rock drilling unit and a rock drilling rig. The present disclosure further relates to computer program and a computer- readable medium.

BACKGROUND ART

When performing drilling operations in rock-type materials generally special kinds of drilling rigs are used. There are different types of drilling rigs, wherein "DTH" (down the hole)-drilling rigs and top hammer drilling rigs are two commonly used rigs for such operations being performed in a vertical, or close to vertical, direction. As rock drilling is performed in hard materials special kinds of drill bits are used for such operations. Such drill bits are often heavy and may get oily and dirty when used, and may also after usage comprise sharp edges and/or chips of material which may cause harm to a person when handling such a drill bit. The drill bits will however require maintenance in the form of replacement and/or re-grinding, which in turn leads to a need to remove and attach such drill bits to the drilling rig every now and then.

DTH-drilling rigs generally comprise a spline coupling for attaching a drill bit to such a drilling rig, whereas top hammer drilling rigs in general instead utilize a threaded connection. Drill bit change systems are known, which systems may provide a fully or semi-automatic replacement process for drilling rigs. The drill bit changing systems are designed differently for DTH-drilling rigs and top hammer drilling rigs.

SUMMARY OF THE INVENTION

Due to the above described properties and circumstances surrounding handling of drill bits, such removing and attaching operations are heavy, inconvenient and at times the cause of personal injury. There is thus a need for an improved method for changing an handling such drill bits. There is also a need to develop an improved control device configured to perform drill bit change operations to a rock drilling unit automatically or at least semi-automatically. There is also a need to develop a rock drilling unit comprising such a control device, a rock drilling rig comprising such a rock drilling unit, a computer program and a computer-readable medium for executing the method. There is also a need to develop a rock drilling unit and a rock drilling rig which may be autonomously controlled.

An object of the invention is thus to provide an improved method for changing and handling drill bits. A further object is to develop an improved control device configured to perform drill bit change operations to a rock drilling unit automatically or at least semi-automatically. Additional objects are respectively to develop a rock drilling unit comprising such a control device, a rock drilling rig comprising such a rock drilling unit, a computer program and a computer-readable medium for executing the method. A further object is to develop a rock drilling unit and a rock drilling rig which may be autonomously controlled.

These objects are achieved by a method performed by a control device for changing a drill bit in a rock drilling unit, a control device of a rock drilling unit, rock drilling unit and a rock drilling rig a computer program and a computer-readable medium according to the appended claims.

According to an aspect of the invention, a method performed by a control device for changing a drill bit in a rock drilling unit is provided. The drill bit is configured to be connected to at least one drill rod by a first threaded connection. The rock drilling unit comprising: a first feeding device for feeding the at least one drill rod and the drill bit in an axial direction; a rotating device, which is configured to generate a rotational movement of the at least one drill rod and the drill bit; an impact device for providing impact pulses on the at least one drill rod and the drill bit; and a drill bit changer for changing drill bits on the at least one drill rod, the method comprising: receiving information about changing the drill bit; controlling the impact device for punching the drill bit against a bottom of a formed drill bore for loosen the first threaded connection between the drill bit and the at least one drill rod; controlling the first feeding device for moving the at least one drill rod and the drill bit out of the drill bore; controlling the rotating device for removing the drill bit from the at least one drill rod; controlling the drill bit changer for changing and replacing the drill bit; and controlling the rotating device for attaching the at least one drill rod to the drill bit by the first threaded connection.

This has the advantage that instructions from the control device may control the first feeding device, the rotating device and the impact device for changing a drill bit by means of the drill bit changer. The instructions from the control device may be based on information received from sensors and from experience data. The control device may be configured to initiate the changing of a drill bit based on operational data of the drilling rig and the drill bit connected to the drilling rig. Thus, a drill bit changing operation may be initiated automatically between drilling operations if a need for such an operating is detected based on the operational data. The operational data may be data comprising any one or a combination of: time spent drilling, time spent drilling since last maintenance, expected time left until change is needed, meters drilled, meters drilled since last maintenance, or other. The control device may thus initiate a drill bit changing operation if the current state of a drill bit is deemed as not in shape for drilling in an upcoming drilling operation. As a result, a plurality of drilling operations after each other may be performed in a safe, fast and efficient manner. The object to provide an improved method for changing and handling drill bits is thus achieved.

According to an aspect of the invention, a computer program comprising instructions which, when the program is executed by a computer, cause the computer to carry out the method. A computer-readable medium comprising instructions, which when executed by a computer, cause the computer to carry out the method. This has the advantage that the method may be comprised in pre-programmed software, which may be implemented into the drilling unit suitable for utilizing the method.

According to an aspect of the invention, a control device of a rock drilling unit is provided. The rock drilling unit comprises: a drill bit, which is configured to be connected to at least one drill rod by a first threaded connection; a first feeding device for feeding the at least one drill rod and the drill bit in an axial direction; a rotating device, which is configured to generate a rotational movement of the at least one drill rod and the drill bit; an impact device for providing impact pulses on the at least one drill rod and the drill bit; and a drill bit changer for changing drill bits on the at least one drill rod, the control device being configured to: receive information about changing the drill bit; control the impact device for punching the drill bit against a bottom of a formed drill bore for loosen the first threaded connection between the drill bit and the at least one drill rod; control the first feeding device for moving the at least one drill rod and the drill bit out of the drill bore; control the rotating device for removing the drill bit from the at least one drill rod; control the drill bit changer for changing and replacing the drill bit; and control the rotating device for attaching the at least one drill rod to the drill bit by the first threaded connection.

This has the advantage that the drill bit change operations to a rock drilling unit may be performed automatically. The first feeding device, the rotating device, the impact device and the drill bit changer are controlled by the control unit to automatically changing the drill bits in a safe manner. The drill bits, which may be heavy, sharp and/or non-comfortable to hold and carry, may be completely handled by means of instructions from the control device. The drill bit change operations are performed by the control device and may be based on information received from sensors and from experience data. The control device may be configured to initiate the changing of a drill bit based on operational data of the drilling rig and the drill bit connected to the drilling rig. Thus, a drill bit changing operation may be initiated automatically between drilling operations if a need for such an operating is detected based on the operational data.

According to an aspect of the invention, a rock drilling unit is provided, wherein the rock drilling unit comprises at least one control device disclosed herein. The rock drilling unit comprises the first feeding device, the rotating device, the impact device and the drill bit changer are controlled by the control unit to automatically changing the drill bits. This has the advantage that the rock drilling unit may be arranged in a rock drilling rig, in order to achieve automatically performed drill bit change operations.

According to an aspect of the invention, a rock drilling rig is provided, which rock drilling rig comprises the rock drilling unit disclosed herein. Different types of drilling rigs may used depending on demands for typical rock drilling. According to an aspect the rock drilling rig may be configured for vertical drilling or drilling in an angled direction, in the range of about 0° to about 95° relative a vertical line. Such rock drilling rig may be a top hammer drilling rig, which utilize a threaded connection for attaching a drill bit to the rock drilling rig.

Further objects, advantages and novel features of the present invention will become apparent to one skilled in the art from the following details, and also by putting the invention into practice. Whereas embodiments of the invention are described below, it should be noted that it is not restricted to the specific details described. Specialists having access to the teachings herein will recognise further applications, modifications and incorporations within other fields, which are within the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

For fuller understanding of the present disclosure and further objects and advantages of it, the detailed description set out below should be read together with the accompanying drawings, in which the same reference notations denote similar items in the various figures, and in which:

Fig. 1 illustrates a view in perspective of a rock drilling rig according to an example;

Fig. 2 schematically illustrates a side view of a rock drilling unit according to an example;

Fig. 3 illustrates a view in perspective of a drill bit changer according to an example;

Fig. 4 schematically illustrates a view in perspective of a gripping arm of a drill bit changer according to an example;

Fig. 5 shows a flowchart of a method according to an example;

Fig. 6 shows a flowchart of a method according to an example; and

Fig. 7 schematically illustrates a control device or computer according to an embodiment.

DETAILED DESCRIPTION

The detailed description with reference to the examples depicted are to be viewed as examples comprising a combination of certain features, which features have been described in detail above. It is thus to be understood that additional examples may be achieved by combining other features into examples not depicted herein. The figures are to be viewed as examples and not mutually exclusive combinations. It should also be noted that all figures shown and described are schematically represented, wherein generic parts of machinery or similar is not depicted for the sake of simplicity.

According to an aspect of the present disclosure, a method performed by a control device for changing a drill bit in a rock drilling unit is provided. The drill bit is configured to be connected to at least one drill rod by a first threaded connection. The rock drilling unit comprising: a first feeding device for feeding the at least one drill rod and the drill bit in an axial direction; a rotating device, which is configured to generate a rotational movement of the at least one drill rod and the drill bit; an impact device for providing impact pulses on the at least one drill rod and the drill bit; and a drill bit changer for changing drill bits on the at least one drill rod, the method comprising: receiving information about changing the drill bit; controlling the impact device for punching the drill bit against a bottom of a formed drill bore for loosen the first threaded connection between the drill bit and the at least one drill rod; controlling the first feeding device for moving the at least one drill rod and the drill bit out of the drill bore; controlling the rotating device for removing the drill bit from the at least one drill rod; controlling the drill bit changer for changing and replacing the drill bit; and controlling the rotating device for attaching the at least one drill rod to the drill bit by the first threaded connection.

The control device may be arranged on the rock drilling unit or at a distance to the rock drilling unit. The control device may be connected to sensors, which are arranged on the rock drilling unit or at components connected to the rock drilling unit. Such sensors may detect activities or characteristics of the rock drilling unit or of the components connected to the rock drilling unit. The control device may comprise a memory in which experience data may be stored.

The drill bit is adapted for rock drilling in hard materials. The drill bit may be designed and provided with a shape adapted to the boring operation to be performed. Such drill bits are often heavy and may after usage comprise sharp edges and/or chips of material. The drill bit is provided with a thread, which is adapted to be connected to a corresponding thread on the drill rod to form a first threaded connection.

The rock drilling unit may comprise an elongated frame or beam, on which the first feeding device, the rotating device and the impact device are arranged. The rock drilling unit may be arranged on and connected to a vehicle by means of a boom, so that the rock drilling unit can be arranged in different positions in relation to the vehicle and to the rock to be drilled. Together, the rock drilling unit, the boom and the vehicle form a rock drilling rig. The drilling unit may be configured for vertical drilling, which is to be perceived as completely vertical or deviating from vertical to some extent. The drilling unit may thus be able to be tilted and drill at an angled direction, in the range of about 0° to about 95° relative a vertical line without deviating from the scope of the disclosure. Such rock drilling unit configured for vertical drilling or drilling in an angled direction, in the range of about 0° to about 95° relative a vertical line, in rock drilling rig may be configured as a top hammer drilling rig.

The drilling unit may also be provided with a drill bit changer, which assists in the automatically changing of drill bits. The drill bit changer may comprise a drill bit storage device, arranged adjacent and parallel with a drill centre axis of the rock drilling unit and being arranged to hold a plurality of drill bits and to move drill bits between storage positions and an exchange position comprised therein. The drill bit storage device may have a cylindrical drum shape, wherein the movement between internal positions within the drill bit storage device may be performed by rotation of such a cylindrical storage device, or by means of a rotation of internal parts thereof. The drill bit storage device may of course have other designs without deviating from the scope of the disclosure herein.

The rock drilling unit may also be provided with a rod handling system, which comprises gripping elements for drill rods. The rod handling system comprises a magazine of drill rods. The drill rods may be brought from the magazine by the gripping elements during the boring operation for assembling a bore string with drill rods and thus make it possible to bore deeper into the rock. When changing drill bit, the drill rods are disassembled from each other and successively are brought back to the magazine by the gripping elements. The first feeding device is configured for feeding the drill rod and the drill bit in an axial direction, both during the drilling operation and also during changing of a drill bit. The first feeding device may be axially driven in relation to the rock drilling unit and in the direction of the drill centre axis by means of a hydraulic or pneumatic actuator.

The rotating device, which is configured to generate a rotational movement of the drill rod and the drill bit may be driven by a first hydraulic or pneumatic machine. The impact device for providing impact pulses on the at least one drill rod and the drill bit may be driven by a second hydraulic or pneumatic machine. The impact pulses are provided on the drill rod in the direction of the drill centre axis and the impact pulses are transferred from the drill rod to the drill bit.

By the method step receiving information about changing the drill bit, the control device may receive information from a memory in which operational data are stored. Alternatively or in combination, the control device may receive information from a device, which provides operational data. The operational data may be data comprising any one or a combination of: time spent drilling, time spent drilling since last maintenance, expected time left until change is needed, meters drilled, meters drilled since last maintenance, or other.

By the method step controlling the impact device for punching the drill bit against a bottom of a formed drill bore for loosen the first threaded connection between the drill bit and the at least one drill rod, the control device communicates with the impact device and sends signals for controlling the impact device. The time, frequency of punching the drill bit and punching force may be controlled depending on the type of rock and type of used drill bit.

By the method step controlling the first feeding device for moving the at least one drill rod and the drill bit out of the drill bore, the control device communicates with the first feeding device and sends signals for controlling the first feeding device. The feeding rate and feeding distance of the first feeding device may be controlled depending on the depth of the drilled bore in the rock. By the method step controlling the rotating device for removing the drill bit from the at least one drill rod, the control device communicates with the rotating device and sends signals for controlling the rotating device. The rotational speed and torque of rotating device may be controlled depending on the condition of the first threaded connection.

By the method step controlling the drill bit changer for changing and replacing the drill bit, the control device communicates with the drill bit changer and sends signals for controlling the drill bit changer. The control device may thus control the drill bit storage device and the gripping arm comprised in the drill bit changer.

By the method step controlling the rotating device for attaching the at least one drill rod to the drill bit by the first threaded connection, the control device communicates with the rotating device and sends signals for controlling the rotating device. The rotational speed and torque of rotating device may be controlled depending on the drill rod, the type of drill bit and/or the type of first threaded connection between the drill rod and the drill bit.

A fast and efficient method is provided, for automatically or at least semi-automatically changing of drill bits in a rock drilling unit. The method may handle the potentially harmful drill bits and their potential additional coupling parts without the need for manual work which in turn provides an increased safety and personal safety at a drilling site where said method if performed. As should be realized, the method as presented herein may provide additional benefits coupled to the various optional features of the drill bit changer according to the disclosure.

According to an aspect, after controlling the drill bit changer for changing the drill bits, and before controlling the rotating device for attaching the at least one drill rod to the drill bit by the first threaded connection, the method further comprises: controlling a second feeding device of the rock drilling unit for moving a support device to a position where the support device abuts the drill bit.

In this method step, the control device communicates with the second feeding device and sends signals for controlling the second feeding device. The feeding rate and feeding distance of the second feeding device may be controlled depending on the type of drill bit. The second feeding device may be axially driven in relation to the rock drilling unit and in the direction of the drill centre axis by means of a hydraulic or pneumatic actuator. The support device may be a lower support device of the rock drilling unit arranged for supporting and/or holding/gripping a drill bit or a drill rod. Thus, the drill bit may be supported by the support device, so that the drill bit rests or abuts the support device. Alternatively, the support device is moved to a position, so that the support device may grip the drill bit. In case the drill bit may be supported by the support device, the support device should be arranged below the drill bit, so as to support a drill bit from underneath when held by the gripping means. Moving the support device to a position, so that the support device supports the drill bit from underneath has the advantage that a wide range of drill bits having different designs may be changed in the rock drilling unit. As the type and design of drill bit may vary depending on the type of drilling rig, the gripping means may not be able to hold the drill bit without additional lower support, which may thus be provided by support device. By means of such a synchronized movement of the gripping means and the support device, changing of drill bits may thus increase its usage and be used for various types of drilling units. The support device of the drilling unit may comprise two hydraulically controlled gripping devices, arranged circumferentially around, and at separate positions along, the drill centre axis. Moving the gripping devices to a position close to each other will provide a support underneath the drill bit. The support device may be connected to the control device.

According to an aspect, after controlling the first feeding device for moving the at least one drill rod and the drill bit out of the drill bore, and before controlling the rotating device for removing the drill bit from the at least one drill rod, the method further comprises: controlling gripping elements of a rod handling system for gripping the at least one drill rod, which is connected to the rotating device; and controlling the rotating device for tightening a second threaded connection between the at least one drill rod and the rotating device.

In this method step, the control device communicates with the gripping elements of the rod handling system and the rotating device and thus sends signals for controlling the gripping elements of the rod handling system and the rotating device. During the step of punching the drill bit against the bottom of the formed drill bore for loosen the first threaded connection between the drill bit and the at least one drill rod, also the second threaded connection between the drill rod and the rotating device may be loosened. The gripping elements, which bring drill rods from and to the magazine of the rod handling system may be controlled to firmly gripping the drill rod which is connected to the rotating device in order to tightening the second threaded connection between the at least one drill rod and the rotating device. Thereafter, the rotating device may be controlled for tightening the second threaded connection.

According to an aspect, receiving information about changing the drill bit is based on the drilling condition of the drill bit.

By this method step, the control device may receive information from a sensor or a similar detector element. For example, the sensor or similar detector element may sense any differences in or characteristics of the torque from the rotating device and/or characteristics from the impact device in order to determine the state of the drill bit.

According to an aspect, controlling the drill bit changer for changing and replacing the drill bit comprising moving the drill bit from a drill centre axis to a drill bit storage device by means of a gripping arm and thereafter retrieving a new drill bit from the drill bit storage device and moving it to the drill centre axis.

The drill bit storage device may comprise a number of storage position for holding drill bits. Each storage position may hold one drill bit, which may be a ready to use drill bit or a drill bit used in a previous drilling operation. The exchange position may be the single position within the storage device from which a drill bit may be retrieved or positioned, wherein the internal movement of the storage device may be used to position a desired slot for holding a specific drill bit at the exchange position. The drill bit changer may further comprise a gripping arm comprising gripping means configured for selective gripping of a drill bit, the gripping arm being arranged to move the gripping means between the exchange position and the drill centre axis of the drilling unit. The gripping arm and the gripping means may be hydraulically controlled, wherein movement and gripping of the two may be exerted with high precision and apply large forces to said functions. Furthermore, as the gripping arm only needs to move to a single position within the drill bit storage device, the movement of the gripping arm may be performed by means of a pivoting motion which reduces the complexity of the gripping arm and its design.

The present disclosure also relates to a computer program comprising instructions which, when the program is executed by a computer, causes the computer to carry out the method disclosed above. The invention further relates to a computer-readable medium comprising instructions, which when executed by a computer causes the computer to carry out the method disclosed above. The method may be comprised in pre-programmed software, which may be implemented into the drilling unit suitable for utilizing the method. The pre programmed software may be stored in the control device. Alternatively, or in combination, the software may be stored in a memory or in computer at a distance from the control device.

Furthermore, the present disclosure relates to a control device of a rock drilling unit, the rock drilling unit comprising: a drill bit, which is configured to be connected to at least one drill rod by a first threaded connection; a first feeding device for feeding the at least one drill rod and the drill bit in an axial direction; a rotating device, which is configured to generate a rotational movement of the at least one drill rod and the drill bit; an impact device for providing impact pulses on the at least one drill rod and the drill bit; and a drill bit changer for changing drill bits on the at least one drill rod, the control device being configured to: receive information about changing the drill bit; control the impact device for punching the drill bit against a bottom of a formed drill bore for loosen the first threaded connection between the drill bit and the at least one drill rod; control the first feeding device for moving the at least one drill rod and the drill bit out of the drill bore; control the rotating device for removing the drill bit from the at least one drill rod; control the drill bit changer for changing and replacing the drill bit; and control the rotating device for attaching the at least one drill rod to the drill bit by the first threaded connection.

This has the advantage that the drill bit change operations to a rock drilling unit may be performed automatically. The first feeding device, the rotating device, the impact device and the drill bit changer are controlled by the control unit to automatically changing the drill bits in a safe manner. The drill bits, which may be heavy, sharp and/or non-comfortable to hold and carry, may be completely handled by means of instructions from the control device. The drill bit change operations are performed by the control device and may be based on information received from sensors and from experience data. The control device may be configured to initiate the changing of a drill bit based on operational data of the drilling rig and the drill bit connected to the drilling rig. Thus, a drill bit changing operation may be initiated automatically.

It will be appreciated that all the examples described for the method aspect of the disclosure performed by the control device are also applicable to the rock drilling unit, the rock drilling rig and the control device aspect of the disclosure. That is, the control device may be configured to perform any one of the steps of the method according to the various examples described above. Thus, according to the following aspects, the control device may be configured to perform the method steps according to the corresponding examples described above.

According to an aspect, the control device may thus be configured to control a second feeding device of the rock drilling unit for moving a support device to a position where the support device abuts the drill bit. According to a further aspect, the control device may be configured to control gripping elements of a rod handling system for gripping the at least one drill rod, which is connected to the rotating device; and to control the rotating device for tightening a second threaded connection between the at least one drill rod and the rotating device. According to a further aspect, the received information about changing the drill bit is based on the drilling condition of the drill bit. According to a further aspect, the drill bit changer for changing and replacing the drill bit is controlled by moving the drill bit from a drill centre axis to a drill bit storage device by means of a gripping arm and thereafter retrieving a new drill bit from the drill bit storage device and moving it to the drill centre axis.

The control device may be implemented as a separate entity or distributed in two or more physical entities. The control device may comprise one or more computers. The control device may thus be implemented or realised by the control device comprising a processor and a memory, the memory comprising instructions, which when executed by the processor causes the control device to perform the herein disclosed method. Furthermore, the present disclosure relates to a rock drilling unit comprising: a drill bit is configured to be connected to at least one drill rod by a first threaded connection; a first feeding device for feeding the at least one drill rod and the drill bit in an axial direction; a rotating device, which is configured to generate a rotational movement of the at least one drill rod and the drill bit; an impact device for providing impact pulses on the at least one drill rod and the drill bit; and a drill bit changer for changing drill bits on the at least one drill rod, wherein the rock drilling unit comprises at least one control device as disclosed herein.

The rock drilling unit may comprise an elongated frame or beam, on which the first feeding device, the rotating device and the impact device are arranged. The rock drilling unit may be arranged on and connected to a vehicle by means of a boom, so that the rock drilling unit can be arranged in different positions in relation to the vehicle and to the rock to be drilled. Together, the rock drilling unit, the boom and the vehicle form a rock drilling rig. The drilling unit may be configured for vertical drilling, which is to be perceived as completely vertical or deviating from vertical to some extent. The drilling unit may thus be able to be tilted and drill at an angled direction, in the range of about 0° to about 95° relative a vertical line without deviating from the scope of the disclosure. Such rock drilling unit configured for vertical drilling or in an angled direction, in the range of about 0° to about 95° relative a vertical line, in rock drilling rig may be configured as a top hammer drilling rig.

The control device may be arranged on the rock drilling unit or at a distance to the rock drilling unit. The control device may be connected to sensors, which are arranged on the rock drilling unit or at components connected to the rock drilling unit. Such sensors may detect activities or characteristics of the rock drilling unit or of the components connected to the rock drilling unit. The control device may comprise a memory in which experience data may be stored.

The drilling unit may also be provided with a drill bit changer, which assists in the automatically changing of drill bits. The drill bit changer may comprise a drill bit storage device, arranged adjacent and parallel with a drill centre axis of the rock drilling unit and being arranged to hold a plurality of drill bits and to move drill bits between storage positions and an exchange position comprised therein. The drill bit storage device may have a cylindrical drum shape, wherein the movement between internal positions within the drill bit storage device may be performed by rotation of such a cylindrical storage device, or by means of a rotation of internal parts thereof. The drill bit storage device may of course have other designs without deviating from the scope of the disclosure herein.

The rock drilling unit may also be provided with a rod handling system, which comprises gripping elements for drill rods. The rod handling system comprises a magazine of drill rods. The drill rods may be brought from the magazine by the gripping elements during the boring operation for assembling a bore string with drill rods and thus make it possible to bore deeper into the rock. When changing drill bit, the drill rods are disassembled from each other and successively are brought back to the magazine by the gripping elements.

The first feeding device is configured for feeding the drill rod and the drill bit in an axial direction, both during the drilling operation and also during changing of a drill bit. The first feeding device may be axially driven in relation to the rock drilling unit and in the direction of the drill centre axis axis by means of a hydraulic or pneumatic actuator.

The rotating device, which is configured to generate a rotational movement of the drill rod and the drill bit may be driven by a first hydraulic or pneumatic machine. The impact device for providing impact pulses on the at least one drill rod and the drill bit may be driven by a second hydraulic or pneumatic machine. The impact pulses are provided on the drill rod in the direction of the drill centre axis and the impact pulses are transferred from the drill rod to the drill bit.

According to an aspect, the drill bit changer comprises a drill bit storage device for drill bits and a gripping arm for moving drill bits between the drill bit storage device and a drill centre axis.

The drill bit storage device may comprise at least one drill bit sensor, arranged to monitor drill bits located in the positions of the drill bit storage device. Thus, the control device may be provided with information regarding not only a present drilling operation but also for drilling operations to be performed at a later point in time. As the drill bit storage device may hold a plurality of drill bits, the control device may in a fast and easy manner monitor how many drill bits are present in the device, wherein planning of drilling operations becomes faster and more efficient. An operator may also receive information from the control device how many drill bits are present in the device.

The control device may further be arranged to determine an operational condition of a drill bit based on its operational data, and to provide a user interface with a signal when drill bit change is needed. Thus, the control device may assist in a continuous monitoring of a plurality of drill bits, which may be utilized so as to maximize the usage of each drill bit in the system. The control device may estimate an operational state of a drill bit based on ingoing operational data coupled with further usage of said drill bit when used for drilling in drilling operation. The operational condition may be determined by the control device and provided to an operator prior to the need of an upcoming drill bit change operation.

The drill bit storage device may comprise an enclosing protective housing. The housing may comprise at least a first door arranged at the exchange position, the first door may be arranged to be selectively opened and closed depending on a drill bit exchange operation being performed. This will result in that the drill bits being stored within the drill bit storage device are protected from dust, dirt, oil or debris or similar, which may be common at a drilling site. The stored drill bits being protected in such a manner increases the longevity of said drill bits and ensures that a drill bit is in good shape and condition when it is drawn from the drill bit storage device to be used in a drilling operation.

The first door of the housing may be coupled to the gripping arm, wherein the first door automatically opens and closes depending on the movement of the gripping arm. This will simplify the operation of the first door as it may be performed completely automatically coupled with the gripping arm. As the first door in general only should be open when a drill bit changing operation is being performed, the opening and closing of said first door may thus in a reliable and efficient manner be synchronized and controlled by the movement of the griping arm during its movement during such an operation.

Furthermore, the present disclosure relates to a rock drilling rig comprising the rock drilling unit as disclosed herein. The rock drilling rig comprises the rock drilling unit as disclosed herein. In addition the rock drilling rig may also comprise a drilling platform, such as a vehicle. Connecting the rock drilling unit to a vehicle results in the rock drilling rig may easily be moved to different places and to different positions between drilling operations. The rock drilling unit may be arranged on and connected to a vehicle by means of a boom, so that the rock drilling unit can be arranged in different positions in relation to the vehicle and to the rock to be drilled.

According to an aspect the rock drilling rig is configured for vertical drilling or in an angled direction, in the range of about 0° to about 95° relative a vertical line

The drilling rig may comprise an interchangeable plurality of drill rods, wherein drill bits may be arranged at an end section of an end drill rod. The drill bit may be attached to the end section by means of a threaded connection. The rock drilling rig is configured for vertical drilling. However, the rock drilling rig may also be configured for drilling in a direction which deviates from vertical drilling. Such rock drilling rig may be configured for drilling in an angled direction, in the range of about 0° to about 95° relative a vertical line.

The drilling rig may be a top hammer drilling rig. This has the advantage that a commonly used drilling rig may be provided having the drill bit changer for at least semi-automatic changing of drill bits according to the disclosure. The commonly used top hammer drilling rig may thus be provided with a reliable and safe system for changing the drill bits of said drilling rig. An efficient and reliable drilling rig is thus provided, which by means of the system arranged thereto provides a safe and convenient work environment due to not having the need to change drill bits manually.

The present invention will now be further illustrated with reference to the appended figures.

Fig. 1 shows a rock drilling rig 5 in a view of perspective according to an example. The rock drilling rig 5 comprises a rock drilling unit 8, which may comprise an elongated frame or beam 2. The rock drilling unit 8 may be arranged on and connected to a vehicle 6 by means of a boom 4, so that the rock drilling unit 8 can be arranged in different positions in relation to the vehicle 6 and to the rock to be drilled. Together, the rock drilling unit 8, the boom 4 and the vehicle 6 form the rock drilling rig 5. The drilling rig 5 is configured for vertical drilling, which is to be perceived as completely vertical or deviating from vertical to some extent. The drilling rig 5 may thus be able to be tilted and drill at an angled direction, in the range of about 0° to about 95° relative a vertical line without deviating from the scope of the disclosure. The drilling rig 5 may comprise an interchangeable plurality of drill rods 7 (fig. 2), arranged to form a drill string within a rock drilling unit 8 of the drilling rig 5. Each drill rod 7 comprises threads providing the option of connecting additional drill rods 7 as a drill bore 50 (fig. 2) being drilled gets deeper. A drill bit 3 is then arranged at an end section of an end drill rod 7, wherein said drill bit 3 may be attached to the end section by means of a first threaded connection 40.

The drilling rig 5 may further comprise a support device 9, such as a lower support device, which may be arranged at a lower portion of the rock drilling unit 8 and being arranged for supporting and/or holding/gripping a drill bit 3 or a drill rod 7, which may be utilized for maintenance and/or assembly/disassembly or such parts. In addition, the support device 9 may guide the drill rod 7.

The drilling rig 5 shown in fig. 1 may further comprise a drill bit changer 1 for automatically or at least semi-automatic changing of drill bits 3. Said drill bit changer 1 is arranged close to ground level and being arranged parallel with a drill centre axis 15 of the drilling unit 8. The term drill centre axis 15 may be perceived as a centre line in a drill bore 50 (fig. 2) being drilled by means of the drilling rig 5. The drill bit changer 1 is thus arranged so as to follow the alignment of the drill centre axis 15 when being used. If the rock drilling unit 8 is being tilted to an angle, the drill bit changer 1 and its ingoing parts may this also be tilted along with the drill centre axis 15 and the drilling unit 8.

Fig. 2 schematically illustrates a side view of a rock drilling unit 8 according to an example.

The drill bit 3 is configured to be connected to a drill rod 7 by the first threaded connection 40. The rock drilling unit 8 comprising a first feeding device 42 is configured for feeding the at least one drill rod 7 and the drill bit 3 in an axial direction. A rotating device 44 is configured to generate a rotational movement of the at least one drill rod 7 and the drill bit 3. An impact device 46 is configured for providing impact pulses on the at least one drill rod 7 and the drill bit 3. The drill bit changer 1 is arranged on the rock drilling unit 8 for changing drill bits 3 on the drill rod 7. The rotating device 44 and the impact device 44 are arranged on the first feeding device 42. The rotating device 44 and the impact device 44 are configured to be displaced by means of the first feeding device 42. The first feeding device 42 is arranged on elongated frame or beam 2. The first feeding device 42 is configured for feeding the drill rod 7 and the drill bit 3 in an axial direction, both during the drilling operation and also during changing of a drill bit 3. The first feeding device 42 may be axially driven in relation to the rock drilling unit 8 and in the direction of the drill centre axis 15 by means of a hydraulic or pneumatic actuator 10. The control device 100 is connected to the first feeding device 42, the rotating device 44, the impact device 46 and to the drill bit changer 1. The control device 100 may be connected to sensors 11, which are arranged on the rock drilling unit 8 or at the components connected to the rock drilling unit 8. The control device 100 may receive information from a memory 12 in which operational data are stored.

The control device 100 is configured to receive information about changing the drill bit 3; to control the impact device 46 for punching the drill bit 3 against a bottom 48 of a formed drill bore 50 for loosen the first threaded connection 40 between the drill bit 3 and the at least one drill rod 7; to control the first feeding device 42 for moving the at least one drill rod 7 and the drill bit 3 out of the drill bore 50; to control the rotating device 44 for removing the drill bit 3 from the at least one drill rod 7; to control the drill bit changer for changing and replacing the drill bit 3; and to control the rotating device 44 for attaching the at least one drill rod 7 to the drill bit 3 by the first threaded connection 40.

In addition, the control device 100 being configured to control a second feeding device 52 moving the support device 9 to a position where the support device 9 abuts the drill bit 3. The second feeding device 52 may be axially driven in relation to the rock drilling unit 8 and in the direction of the drill centre axis 15 by means of a hydraulic or pneumatic actuator. The control device 100 is connected to the second feeding device 52. The support device 9 is connected to the control device 100. The control device 100 is also configured to control gripping elements 54 of a rod handling system 56 for gripping the at least one drill rod 7, which is connected to the rotating device 44; and to control the rotating device 44 for tightening a second threaded connection 58 between the at least one drill rod 7 and the rotating device 44. The rod handling system 56 comprises a magazine 60 of drill rods 7. The control device 100 is connected to the rod handling system 56. The drill bit changer 1 for changing and replacing the drill bit 3 is controlled by moving the drill bit 3 from the drill centre axis 15 to a drill bit storage device 13 by means of a gripping arm 21 and thereafter retrieving a new drill bit 3 from the drill bit storage device 13 and moving it to the drill centre axis 15.

Fig. 3 illustrates a view in perspective of a drill bit changer 1 according to an example, wherein parts of the drilling unit 8 to which the drill bit changer 1 is arranged is also shown in the figure. The drilling unit 8 may be a drilling unit 8 as shown in figures 1 and 2 or similar, wherein the drilling unit 8 may be configured for vertical drilling or drilling in an angled direction, in the range of about 0° to about 95° relative a vertical line. The drilling unit 8 may comprise the magazine 60 of an interchangeable plurality of drill rods 7. The drilling unit 8 may further comprise the lower support device 9. The drilling unit 8 may further comprise an additional support element 14, configured for loosening threaded connections 16 (fig. 2) of the drill rods 7. The additional support element 14 of the drilling unit 8 may comprise two hydraulically controlled gripping devices 27, arranged circumferentially around, and at separate positions along, the drill centre axis 15.

The drill bit changer 1 with the drill bit storage device 13 may be arranged adjacent and parallel with the drill centre axis 15 of the drilling unit 8 and being arranged to hold a plurality of drill bits 3 and to move drill bits 3 between storage positions 17 and an exchange position 19 comprised therein. The drill bit storage device 13 may have a cylindrical drum shape, wherein the movement between internal positions 17, 19 within the drill bit storage device 13 may be performed by rotation of such a cylindrical storage device 13, or by means of a rotation of internal parts thereof. Each storage position 17 may hold one drill bit 3, which may be a ready to use drill bit 3 or a drill bit 3 used in a previous drilling operation. The exchange position 19 may be the single position within the storage device 13 from which a drill bit 3 may be retrieved or positioned, wherein the internal movement of the storage device 13 may be used to position a desired slot for holding a specific drill bit 3 at the exchange position 19. The gripping arm 21 of the drill bit changer 1 may further comprise gripping means 23 configured for selective gripping of a drill bit 3. The gripping arm 21 being arranged to move the gripping means 23 between the exchange position 19 and the drill centre axis 15 of the drilling unit 8. As is shown in fig. 3, the gripping arm 21 and the gripping means 23 may be hydraulically controlled, wherein movement and gripping of the two may be exerted with high precision and apply large forces to said functions. Furthermore, as the gripping arm 21 only needs to move to a single position 19 within the drill bit storage device 13, the movement of the gripping arm 21 may be performed by means of a pivoting motion which reduces the complexity of the gripping arm 21 and its design.

The gripping means 23 may further comprise a sensor 11 (fig. 2), arranged to monitor an operational state of the gripping means 23 and an applied pressure towards a drill bit 3. Such sensor 11 may easily be arranged within or at the hydraulics of the gripping means 23, as the internal pressure of the hydraulic cylinders controlling the gripping movement of the gripping means 23 directly correlates to when the gripping means 23 engages an object. The sensor 11 may thus be utilized to ensure that the gripping means 23 always provides the same amount of gripping force to an object (such as a drill bit) regardless of the size of said object.

The gripping arm 21 may further comprise a sensor 11, arranged to monitor movement of the gripping arm 21. Such sensor 11 may, similar to the sensor 11 for the gripping means 23, be a sensor 11 arranged within or at the hydraulics for controlling the gripping arm 21. Other types of sensors 11 may of course also be used, such as IR-sensors or similar, without deviating from the scope of the disclosure. By means of monitoring the movement of the gripping arm 21, it should be noted that such a monitoring may also be utilized to obtain positional information relating to the position of the gripping arm 21 and thus also the gripping means 23 at any given point in time. Thereby movement and positioning of the gripping arm 21, and deviations thereof, may be monitored with high accuracy and reliability. If for example the gripping arm 21 is to move a drill bit 3 from the drill centre axis 15 and the drill bit 3 for some reason gets stuck in its intended path, the internal pressure of the hydraulics will increase at a non-expected point in time and the sensor 11 may alarm the drill bit changer 1 of an unexpected occurrence.

The drill bit changer 1 is connected to the control unit 100 (fig. 2), arranged to receive input from the sensors 11 and the drilling unit 8, and to control movement of the gripping arm 21, the gripping means 23, the drill bit storage device 13, and the additional support element 14 of the drilling unit 8. The control unit 100 may be arranged within the drill bit changer 1, or at a remote location such as within an operator cabin of the drilling rig 5 for example. The control unit 100 may be coupled to the sensors 11, the drill bit changer 1 and the drilling unit 8 by means of wires or by means of a wireless interface according to known art.

By means of connecting the control unit 100 not only to the drill bit changer 1 and its parts but also to the drilling unit 8 and its parts, the control unit 100 may be able to allow the drilling unit 8 and the drill bit changer 1 to interact and cooperate, which provides more efficient operations performed by the drill bit changer 1. Furthermore, as the control unit 100 may take control over and control machinery such as the additional support element 14 of the drilling unit 8, lesser complex machinery is needed for the drill bit changer 1 itself, which lowers manufacturing costs for the drill bit changer 1.

The drill bit storage device 13 may further comprise at least one drill bit sensor 11, arranged to monitor drill bits 3 located in the positions 17, 19 of the drill bit storage device 13. Such an at least one sensor 11 may be an optical sensor or a pressure sensor or similar, arranged to monitor if a drill bit 3 is positioned in a specific position 17, 19, or a plurality of positions 17, 19 if arranging a plurality of such sensors 11. Such a sensor 11 may also be a more complex sensor device, arranged not only for monitoring positioning within the storage device 13, but also to analyse and evaluate drill bits 3 positioned in the storage device 13. Such a sensor device may scan the surface of a drill bit 3 and compare it to a predetermined surface of a well-functioning drill bit 3, wherein the control unit 100 may provide an operator of the drilling unit 8 with information regarding the state of the drill bits 3 positioned in the storage device 13. Thereby faulty drill bits 3 may be discovered and replaced for a higher operational uptime of such a drilling unit 8.

The control unit 100 may be configured to initiate the automatically or the at least semi automatic changing of drill bits 3 based on operational data of the drilling unit 8 and the drill bit 3 connected to the drilling unit 8. Such operational data may be data comprising any one or a combination of: time spent drilling, time spent drilling since last maintenance, expected time left until change is needed, meters drilled, meters drilled since last maintenance, or other. Such operational data may relate to the drilling unit 8, each drill bit 3 arranged in the drill bit changer 1, or both. By means of taking such operational data into consideration, and by having a drilling scheme available, the control unit 100 may thus automatically initiate a drill bit changing operation in-between drilling of drill bores 50 (fig. 2), if it is determined that the current drill bit 3 will not be operational for the entirety of the next bore 50 to be drilled. Thereby a lot of wasted time may be cut from a drilling scheme comprising a plurality of bores 50, as inspection of the drill bits 3 is not needed in-between bores 50 to be drilled.

The control unit 100 may further be arranged to determine an operational condition of a drill bit 3 based on its operational data, and to provide an interface with a signal when drill bit change is needed. If certain operational data is known beforehand, such as previous time spent drilling, in what type of material etc. for a specific drill bit 3, and said drill bit 3 is used for drilling a bore, the control unit may then monitor and update such operational data so as to provide and update an operational condition for said drill bit 3. If for example a drill bit 3 is estimated to be able to drill for a certain amount of time in a certain type of material, the control unit 100 may add operational time for said drill bit 3 and monitor its usage over time. Such data may then be stored in a memory and kept track of for each specific drill bit 3 in a drill bit changer 1, wherein the drill bits 3 positioned in the storage positions 17 of the drill bit storage device 13 may be monitored with regards to their individual operational conditions. Such information may then be sent to a user interface or similar so as to display the operational conditions for all drill bits 3 available, wherein an operator of a drilling rig 5 may use said information to better plan future drilling operations. The control unit 100 may also plan the drilling operations in combination with a provided drilling scheme, wherein a suitable drill bit 3 is moved to the exchange position 19 when a bore, for which the operational condition of said drill bit 3 is deemed suitable, is to be drilled. By means of allowing the control unit 100 to plan drilling operations in such a manner, and to automatically initiate drill bit changing operations, a lot of time may be saved, and the drill bits 3 may be used to the their combined maximum capacity.

Fig. 4 schematically illustrates a view in perspective of a gripping arm of a drill bit changer 1 according to an example. The gripping arm 21 drill bit changer 1 comprising gripping means 23 configured for selective gripping of a drill bit 3. The gripping arm 21 is in fig. 4 moved to the drill centre axis 15 of the drilling unit 8 and above the support device 9. The support device 9 may be a lower support device of the rock drilling unit 8 arranged for supporting and/or holding/gripping a drill bit 3 or a drill rod 7. Thus, the drill bit 3 may be supported by the support device 9, so that the drill bit 3 rests on or abuts the support device 9. Alternatively, the support device 9 is moved to a position, so that the support device 9 may grip the drill bit 3. In case the drill bit 3 may be supported by the support device 9, the support device 9 should be arranged below the drill bit 3, so as to support a drill bit 3 from underneath when held by the gripping means 23. Moving the support device 9 to a position, so that the support device 9 supports the drill bit 3 from underneath has the advantage that a wide range of drill bits 3 having different designs may be changed in the rock drilling unit 8. As the type and design of drill bit 3 may vary depending on the type of drilling rig 5, the gripping means 23 may not be able to hold the drill bit 3 without the support device 9, which may thus be provided by support device 9. By means of such a movement of the gripping means 23 and the support device 9, changing of drill bits 3 may thus increase its usage and be used for various types of drilling units 8.

Fig. 5 shows a flowchart of a method according to an example. The method is performed by a control device 100, for changing a drill bit in a rock drilling unit 8. The method thus relates to the controlling of changing a drill bit 3 in a rock drilling unit 8 disclosed in figures 1-4. The rock drilling unit 8 comprising: a first feeding device 42 for feeding the at least one drill rod 7 and the drill bit 3 in an axial direction; a rotating device 44, which is configured to generate a rotational movement of the at least one drill rod 7 and the drill bit 3; an impact device 46 for providing impact pulses on the at least one drill rod 7 and the drill bit3 ; and a drill bit changer 1 for changing drill bits 3 on the at least one drill rod 7.

The method comprising: receiving slOl information about changing the drill bit 3; controlling sl02 the impact device 46 for punching the drill bit 3 against a bottom 48 of a formed drill bore 50 for loosen the first threaded connection 40 between the drill bit 3 and the at least one drill rod 7; controlling sl03 the first feeding device 42 for moving the at least one drill rod 7 and the drill bit 3 out of the drill bore 50; controlling sl04 the rotating device 44 for removing the drill bit 3 from the at least one drill rod 7; controlling sl05 the drill bit changer 1 for changing and replacing the drill bit 3; and controlling sl06 the rotating device 44 for attaching the at least one drill rod 7 to the drill bit 3 by the first threaded connection 40.

Fig. 6 shows a flowchart of a method according to an example. The method is performed by a control device 100, for changing a drill bit 3 in a rock drilling unit 8. The method thus relates to the controlling of changing a drill bit 3 in a rock drilling unit 8 disclosed in figures 1 - 4. The method comprising: receiving slOl information about changing the drill bit 3; controlling sl02 the impact device 46 for punching the drill bit 3 against a bottom 48 of a formed drill bore 50 for loosen the first threaded connection 40 between the drill bit 3 and the at least one drill rod 7; controlling sl03 the first feeding device 42 for moving the at least one drill rod 7 and the drill bit 3 out of the drill bore 50; controlling sl04 the rotating device 44 for removing the drill bit 3 from the at least one drill rod 7; controlling sl05 the drill bit changer 1 for changing and replacing the drill bit 3; and controlling sl06 the rotating device 44 for attaching the at least one drill rod 7 to the drill bit 3 by the first threaded connection 40.

After controlling sl05 the drill bit changer 1 for changing the drill bits 3, and before controlling sl06 the rotating device 44 for attaching the at least one drill rod 7 to the drill bit 3 by the first threaded connection 40, the method further comprises: controlling sl07 a second feeding device 52 of the rock drilling unit 8 for moving a support device 9 to a position where the support device 9 abuts the drill bit 3.

After controlling sl03 the first feeding device 42 for moving the at least one drill rod 7 and the drill bit 3 out of the drill bore 50, and before controlling sl04 the rotating device 44 for removing the drill bit 3 from the at least one drill rod 7, the method further comprises: controlling sl08 gripping elements 54 of a rod handling system 56 for gripping the at least one drill rod 7, which is connected to the rotating device 44; and controlling sl09 the rotating device 44 for tightening a second threaded connection 58 between the at least one drill rod 7 and the rotating device 44.

Figure 7 is a diagram of a version of a device 500. The control device 100 described with reference to fig. 2 and fig. 3 may in a version comprise the device 500. The device 500 comprises a non-volatile memory 520, a data processing unit 510 and a read/write memory 550. The non volatile memory 520 has a first memory element 530 in which a computer programme, e.g. an operating system, is stored for controlling the function of the device 500. The device 500 further comprises a bus controller, a serial communication port, I/O means, an A/D converter, a time and date input and transfer unit, an event counter and an interruption controller (not depicted). The non-volatile memory 520 has also a second memory element 540. There is provided a computer programme P which comprises routines for controlling the rock drilling rig 5. The programme P may be stored in an executable form or in a compressed form in a memory 560 and/or in a read/write memory 550.

Where the data processing unit 510 is described as performing a certain function, it means that the data processing unit 510 effects a certain part of the programme stored in the memory 560 or a certain part of the programme stored in the read/write memory 550.

The data processing device 510 can communicate with a data port 599 via a data bus 515. The non-volatile memory 520 is intended for communication with the data processing unit 510 via a data bus 512. The separate memory 560 is intended to communicate with the data processing unit 510 via a data bus 511. The read/write memory 550 is adapted to communicating with the data processing unit 510 via a data bus 514.

When data are received on the data port 599, they are stored temporarily in the second memory element 540. When input data received have been temporarily stored, the data processing unit 510 is prepared to effect code execution as described above.

Parts of the methods herein described may be effected by the device 500 by means of the data processing unit 510 which runs the programme stored in the memory 560 or the read/write memory 550. When the device 500 runs the programme, methods herein described are executed.

The foregoing description of the embodiments has been furnished for illustrative and descriptive purposes. It is not intended to be exhaustive, or to limit the embodiments to the variations described. Many modifications and variations will obviously be apparent to one skilled in the art. The embodiments have been chosen and described in order to best explicate principles and practical applications, and to thereby enable one skilled in the arts to understand the invention in terms of its various embodiments and with the various modifications that are applicable to its intended use. The components and features specified above may, within the framework of the disclosure, be combined between different embodiments specified.