FIELD OF THE INVENTION The present invention relates to a door lock with a position sensor that measures the relative position of the lock element, for example lock bolt, with respect to locking and unlocking a door.

BACKGROUND OF THE INVENTION

In order to ease operation of door locks, various types of electromechanical lock actuators are known. Often, an electrical motor drives a rotational axis, which via spindle and/or gear wheels moves a lock bolt inside the lock in the door. A worm gear is described in US patent No. 6400278 and International patent application WO2013/116265, and a sprocket gearing is disclosed in WO2005/024160.

In some cases, the door lock can be operated by hand in addition to the motorised actuation; this is explained in WO2013/116265, for example. In order to measure the locked or unlocked status of the lock, there are provided cooperating electrical wiper contacts and conducting zones on a gear wheel indicating the status of the lock bolt when the corresponding contacts and wipers are in electrical contact with each other, as disclosed in WO2013/116265. Alternatively, Hall elements are used in cooperation with magnets in order to reveal the position of the lock bolt, for example as disclosed in WO2005/024160. As locks can be mounted in right-handed doors and in left-handed doors, the electrical conducting zones for the wipers or the magnets for the Hall elements are provided symmetrically on either side of a middle position, thus, indicating open and locked position for a door irrespectively whether it is a right handed or left handed door. Generally, as mentioned in German patent application DE3941086, Hall elements are preferred to electromechanical micro-switches for greater reliability less sensitivity to dirt and humidity. However, the proposed technical solutions in the prior art are not always suitable for post-mounting or retrofitting on existing doors. For example, for fixed positions of hall sensor and magnets on a gear wheel, or wipers and conducting zones, the rotation of the gear wheel may not be sufficient for the magnets to reach the Hall elements or the conductors to reach the wipers in case of a lock with a short lock-bolt actuation length. On the other hand, a very long lock bolt actuation length may turn the gear wheel too much so that the conducting lines pass the wipers, or the magnets pass the Hall elements, such that no status of the lock can be determined. For this reason, the prior art actuators are most useful for locks for which they are specially designed or existing locks that have approximately the same specifications with respect to actuation lengths of the lock bolt.

It would be desirable, however, to have door lock actuators for retrofitting and which have a greater degree of freedom with respect to the lock bolt actuation length on ex- isting door locks.

DESCRIPTION / SUMMARY OF THE INVENTION

It is therefore the object of the invention to provide electromechanical door lock actua- tors that are suitable also for manual operation and which have a simple mechanism indicating whether a door has been locked or unlocked, irrespective of whether the locking element in the lock, typically lock bolt, has a short or long actuation length and irrespective of the direction of locking in right handed or left handed doors. This objective is achieved with a door lock actuation system as described in the following.

The actuation system comprises a casing and inside the casing an electrical motor and an actuator driven by the motor for actuating the locking element in the door lock, typically a lock bolt, in a first direction for locking and in a second, opposite direction for unlocking the door lock. For moving the locking element, typically lock bolt, the actuator is mechanically connected to the locking element, for example via a rotating driver that transfers the power from the motor to the locking element. The rotating driver, optionally, comprises a lock pin, which is typically used in door locks. For example, in order to rotate the lock pin, the actuator comprises a pin receiver having a slot into which the pin in inserted for connection to the actuator.

Furthermore, in order to measure the rotation, the actuator comprises a positioning element that moves in a direction of movement when the actuator is driven by the mo- tor. The positioning element is provided with a plurality of indentations or openings having a spacing period along the direction of movement. Advantageously, the indentations or openings are equidistant, thus, have a fixed distance and period.

Inside the casing, there is further provided a sensor system with at least two micro- switches mutually spaced a distance apart along the direction of movement. Each micro-switch comprises a contact- switching moveable part arranged for moving in and out of the alternating indentations or openings during movement of the positioning element along the direction of movement and thereby creating on-off signals in dependence of whether the contact- switching moveable part is inside or outside an indentation or opening. Thus, when the positioning element is moving, for example linearly or rotationally, the on-off signals by the micro-switches can be used to count the number of indentations that have passed by the micro-switches, from which the moving distance can be determined. For example, the positioning element is provided rotational about a rotation axis and wherein the indentations or openings are spaced along a circle centred on the rotation axis.

Advantageously, the distance between the micro-switches is smaller or larger than a spacing period or a whole number of spacing periods. By such an arrangement, the direction of the positioning element passing the micro-switches can be determined. This is so, because the different spacing implies that the contact- switching movable part of the micro switches do not enter an indentation at the same time but slightly offset in time. The offset reveals whether the movement of the positioning element is in one direction or the opposite direction. The sensor system also comprises a detection unit electrically connected to the micro- switches and programmed to determine on the basis of the timing of received on-off signals from the micro-switches a direction of movement of the positioning element in one or an opposite direction. It is also programmed to count the number of on-off sig- nals and from this number determine the distance of the movement of the positioning element. Typically, the detection unit is an integral part of a control module which is also used for general programming of the door lock and for wireless digital communication, for example with a cell phone for receiving digital commands for locking and unlocking.

In some embodiments, the motor inside the casing is connected to a rotational driving element via a gear worm or gear wheel system for rotationally driving the rotational driving element by the motor. Optionally, the rotational driving element comprises a mechanical connector, typically rotational connector, optionally lock pin, for connec- tion to a locking element, typically lock bolt. In certain embodiments, a gearwheel of the gearwheel system comprises the positioning element. Alternatively, the rotational driving element comprises the positioning element. In a practical embodiment, the rotational driving element comprises a pin receiver configured for receiving a lock pin from a door lock, the lock pin being connected to the locking element such that rotation of the lock pin actuates the locking element. For example, such pin receiver is provided with a slot into which the pin is inserted.

For manual actuation, as alternative or in addition to a motor driven actuator, the actuation system comprises a handle for operating the door lock. The handle is functionally connected to the actuator for driving the actuator by manually driving the handle.

The objective is also achieved by a method for operating an actuation system as described above. The method comprises driving the actuator by the motor and thereby moving the connected positioning element pass the micro-switches and thereby creat- ing a plurality of series of on-off signals from the plurality of micro-switches. The plurality of on-off signals are time-wise shifted due to the distance between the micro- switches being smaller or larger than the spacing period or a plurality of spacing periods of the indentations or openings in the positioning element. Further the method comprises receiving the time-wise shifted plurality of series of on-off signals by the detection unit and determining from the time-wise shift, on the basis of predetermined criteria, whether the positioning element is moving in the first or the second, opposite direction.

Optionally, the method comprises, actuating the actuator and thereby moving the positioning element, until the door changes between a locked state and an unlocked state; during the actuating, by the detection unit determining the direction of movement of the positioning element and counting the number of on-off signals during the actuation and storing the number is a memory. This number is then used subsequently for restricting the movement of the actuator to less than a maximum range of movement of the actuator, thereby minimizing time and electrical consumption during locking and unlocking. The actuation system advantageously comprises a control module in which the detection system is integrated. Optionally, the control module is connected to a wireless transceiver in order to communicate by wireless digital communication with corresponding command terminals, for example a computer, optionally a mobile telephone. The latter can be equipped with a suitable operating system and user interface in order for a user to operate the lock by the cell phone. Typically, the user would use a pointer action on a touch sensitive screen of the cell phone on which screen a correspondingly programmed user interface is provided.

SHORT DESCRIPTION OF THE DRAWINGS

The invention will be explained in more detail with reference to the drawing, where FIG. 1 is a drawing of an actuation system in perspective a) front view and b) view;

FIG. 2 is a cut-open view of an actuation system;

FIG. 3 is a cut-open view of an alternative actuation system:

FIG. 4 is a sketch of a micro-switch useful for the actuation system,

FIG. 5 is a principle sketch of an actuation system; FIG. 6 is an explanatory scheme for the functioning of the micro-switches and the positioning element, where a)-d) illustrates various situations of the micro- switches where positioning element is incrementally moving to the right;

FIG. 7 illustrates the signal sequence during movement of the positioning element; FIG. 8 shows illustrations of parts of the actuation system with a) the back plate with motor, gear and micro-switches; and b) the second gear wheel in greater detail.

DETAILED DESCRIPTION / PREFERRED EMBODEVIENT FIG. 1 shows an example of a door lock actuator unit 1 in perspective view, where FIG. la is a front view and FIG. lb is a rear view. The actuator unit 1, as illustrated, is suitable for post-mount and retrofit on door locks as explained in the following.

The actuator system 1 comprises a casing 1 ' with a front plate 2 with a passive visual indicator 3 that shows the rotational position of the front plate 2. Around its central part 2', the front plate 2 is provided with a circle of small windows 4 through which or from which the light from diodes is transmitted. Optionally, corresponding diodes can be provided behind the windows or inside the windows. For example, a green light transmission indicates that the door is unlocked, whereas a red light indicates that the door is locked. The front plate is fastened by a snap-lock 6 to a cylindrical handle 5. The cylindrical handle 5 forms part of the casing and is mounted rotationally about a central rotation axis 5' and can be used for opening the lock manually. If the door lock is opened electrically, the cylindrical handle 5 would be driven by a motor, whereas it can also be used manually for opening a door from inside a dwelling or commercial building.

FIG. lb illustrated the actuator unit in perspective rear view. An adapter plate 11 constitutes the rear of the actuator unit 1. The adapter plate 11 is provided with a row of pairs of elongate openings 10 as mounting holes for pairs of bolts in order to mount it onto a door in various orientations and positions. Typically, the adapter plate 11 is mounted onto the door first with screws or bolts, after which the remaining parts of the actuator unit 1 are screwed onto the adapter plate 11 , which for this purpose is provid- ed with corresponding threaded screw holes 7 for screws extending from the front side and into the adapter plate 11.

Typically, the door contains a lock inside the door blade with a locking element, typi- cally lock bolt, that is actuated by rotational connector, optionally a lock pin, that extends into the lock. Typically, such rotational connector is rotated by a lock handle or motor mounted on the door blade or by a key inserted into the lock. For example, the lock handle or motor comprises a receiver for a rotational connector, optionally a lock pin, for providing a connection to the rotational connector to allow the rotation thereof by hand or by the motor. Such lock handles can have various forms. In the present case, the rotational connector, optionally lock pin, is rotated by the actuator unit 1.

With reference to FIG. lb and the cross sectional view in FIG. 2, the actuator unit 1 is equipped with an electrical actuator inside the casing , the actuator comprising an electrical motor 14 powered by batteries 19 and mechanically connected through gearwheel system 17 to a first pin receiver 8a and a second pin receiver 8b for rotating the pin receivers 8a, 8b and thereby actuating the lock in the door. In more detail, the pin receivers 8a, 8b are configured with a slot 9 for receiving the rotational lock pin that drives the locking element in the lock inside the door. The first of the pin receivers 8a is provided centrally, for example with a rotational axis exactly coaxially with the cylinder axis 5' of the cylindrical handle 5 or slightly displaced with respect to the cylinder axis 5', for example a few millimetres, optionally within 5 mm from the cylinder axis. In contrast thereto, the second pin receiver 8b is provided off-centred relatively to the cylinder axis 5' of the cylindrical handle 5, typically a few centimetres off-centred, for example at least 2 cm or at least 3 centimetres. The advantage of having such two pin receivers 8a, 8b is a rich versatility with respect to mounting options. If the distance from the edge of the door to the location of the lock pin is less than the radius of the cylindrical handle 5, the off-centred lock pin receiver 8b is used. Otherwise, the central pin receiver 8a is used, which also has the advantage that the adapter plate 11, and thus the actuator unit 1, would cover even a relatively large access hole that is provided in the door blade for access to the lock inside the door. As an alternative to a pin receiver, the lock is configured for a different type of rotational connector for connection to the locking element ion the door lock, typically lock bolt. As an alternative, only the central pin receiver 8a is provided and not the off-centred pin receiver 8b. The mechanics inside the casing would be modified accordingly.

FIG. 2 is a view into the actuation system from a cut-open side perspective. It also shows the cylindrical axis as a stippled vertical line. Behind the windows 4 in the front plate 2, diodes 22 are provided for indicating the locking status of the door. For example, a green light transmission indicates that the door is unlocked, whereas a red light indicates that the door is locked. The diodes 22 are provided on a printed circuit board (PCB) 21 with an integrated circuit for communication between the motor, the diodes, and an external wireless communication system, such as a WIFI system, a Bluetooth system or another type of wireless radio frequency system. The printed circuit board also has the function as a control module. The front plate 2 is fastened to the cylindrical handle 5 by a snap connection 6. The cylindrical handle 5 is connected to a rear plate 26 by a plain bearing. The plain bearing comprises a groove 23 in the cylindrical handle 5 in cooperation with slider plates 24, 25 in a recess 27 which are used to secure and hold the cylindrical handle 5 in rotational connection to the rear plate 26.

The typical mounting procedure is as follows. The adapter plate 11 is mounted onto the door blade. Subsequently, a pin receiver 8a (or 8b if provided) is pushed over the lock pin from the door lock. While the specific pin receiver 8a is accommodating the lock pin, the rear plate 26 is screwed onto the adapter plate 25. For the latter to be possible, the front plate 2 is removed and re-mounted after the fastening of the rear plate 26 onto the adapter plate 25.

FIG. 3 shows an alternative configuration of a door lock actuator in which the pin receiver 8 is driven by a motor 14 through gear wheel system 17. This door lock actuator also comprises a handle 5 for manual locking or unlocking.

FIG. 4 is a principle sketch of a first micro-switch 12 with a contact-switching movable part 13, which at the instance as illustrated to the left is pressed such that the electrical contacts GND and SIGNAL are short-circuited ("shorted"). In the right illustration, the contact- switching movable part 13 is unpressed such that the contacts GND and SIGNAL are not short-circuited ("unshorted"). Such micro-switch is used to give an electrical signal when the contact- switching movable part 13 is pressed upwards. The concrete configuration and use of the micro-switches is explained below.

FIG. 5 illustrates the actuation system. Under control of an electronic control module 15, an electrical motor 14 drives a first gear wheel 17a which in turn drives a second gearwheel 17b. The second gearwheel 17b is driving a pin 18 which actuates a locking element in the door lock 16, typically lock bolt. By adjusting the number of teeth between the gear wheels 17a, 17b, a proper speed can be provided for driving the locking element.

The control module 15 is provided with a wireless transceiver for receiving digital wireless command signals, for example through a Bluetooth, WiFi, Zigbee or Z-wave wireless communication system, for locking or unlocking the door lock 16. Depending on the digital command signal, the control module 15 causes the motor 14 to drive in one or the opposite direction which translates to driving the pin 18 in one or the other direction in order to push or pull the locking element, typically lock bolt, for locking or unlocking the door lock 16.

The micro-switches 12a, 12b are electrically connected to a detector unit. The detec- tion unit, optionally, is an integral part of the control module 15.

FIG. 6 a-d illustrates various situations of a first micro-switch 12a and a second micro- switch 12b relatively to a positioning element 20 when it is moving to the right. The positioning element 20 comprises indentations 20a and elevations 20b such that the micro-switches 12a, 12b during passing of the positioning element 20 are either short- circuited or not in dependence on whether the micro-switch is within an indentation 20a or on an elevation 20b. As illustrated in FIG. 6a, the distance LI between the micro-switches 12a, 12b is larger than the length L2 that is twice the distance (period) between consecutive intendations 20a. This implies that the micro-switches 12a, 12b do not enter intendations 20a at the same time during movement of the positioning element 20. For example, in the situation as illustrated in FIG. 6b, where the positioning element 20 has moved a distance to the right, the second micro-switch has not yet changed state but the first micro-switch 12a has changed its state from a short circuited state to a non-contact state because the contact-switching moveable part 13 of the first micro-switch 12a has entered an indentation 20a. While the positioning element 20 continues to move in the direction to the right, as illustrated in FIG. 6c, the second micro-switch get to the edge of the indentation 20a. The first micro-switch is still in a non-contact state. At further movement of the positioning element 20, the first micro- switch 12a comes to the edge of an indentation 20a and into a short-circuit state, and the second micro-switch 12b gets into a non-contact state.

Optionally, between the situations as illustrated in FIG. 6c and 6d, both micro-switches are in non-contact state. The sequence is illustrated in FIG. 7. 1 half periods with length 2D and displaced by a quarter period D, the first micro-switch 12a and the second micro-switch 12b are shifting between a short-circuit state and a non-contact state. Due to the delayed shift between the short-circuit state and non-contact state of the second micro-switch 12b relatively to the first micro-switch 12a, the direction of the move- ment of the positioning element 20 can be determined. This is so, because the direction of the positioning element 20 causes either the first or the second micro-switch to change state first. Thus, the timing of whether the first or the second micro-switch changes state first determines the direction, and the number of changes determines the distance of the movement of the positioning element 20 relatively to the micro-switches 12a, 12b. The system is simple but very reliable and yields a precision sufficient for locks to be operated reliably.

In some embodiments, the positioning element 20 is a linear element. Alternatively, is it a wheel with periodic elevations and indentations or openings into which the contact- switching movable part 13 fits during rotational movement of the wheel.

FIG. 8 illustrates an exploded drawing with a rear base plate 23 having a support structure 23' on which there is mounted a first gear wheel 17a that is driven by a motor 14 and which drives a second gear wheel 17b. The second gear wheel 17b, better shown in FIG. 8b, comprises openings 20a and elevations 20b for the purpose of changing the state of the micro-switches 12a and 12b when rotating. As illustrated in FIG. 8a, the micro-switches 12a, 12b are provided on a switch base plate 28, which fits on top of the second gear wheel 17b. The second gear wheel 17b has six openings 20a and six elevations 20b, yielding six periods, each of a length of 60 degrees. In a simple programming model, the resolution for the movement of the gear wheel 17b relatively to the micro-switches is 60 degrees. The precision for the lock is given by the number of rotations of the second gear wheel 17b necessary to shift between a locked and an unlocked state. Such calculation would be done in the control module 15, which is electrically connected to the two micro- switches 12a and 12b

Typically, the range of rotation of the pin for the door lock is larger than necessary for actuation of the lock pin between a locked and unlocked state. When a pin is rotated while connected to a locking element, typically lock bolt, the first part of the rotation does not yet activate the locking element, and only upon some further rotation, the locking element is driven into a locked state from an unlocked state, or vice versa. After the locking or unlocking action has been performed, there is typically still another part of the rotation of the pin that is possible without any further action on the locking element. In order to save electricity and in order to minimize time, the control unit can be programmed to only perform a movement of the positioning element 20 that corresponds to the actuation of the locking element. In this situation, the control module 15 is set into a learning mode and the actuator is set, typically manually, to a state in which the locking element is in a locked or unlocked state; the control module is instructed to regard this position as one endpoint for the range of movement for locking or unlocking. Subsequently, the actuator is set to the corresponding unlocked or locked state of the locking element and the control module instructed to record this as a second endpoint for the movement. The range for the total movement of the actuator and its positioning element is thus shortened as compared to the original, maximum range of motion, where a rotation of the pin would not cause any actuation of the locking element over a part of the actuation. Numbering of elements:

1 actuation system

2 front plate

2' central part

3 passive indicator

4 small windows

5 handle

5' cylinder axis

6 snap lock

7 screw holes

8 pin receiver

8a first pin receiver

8b second pin receiver

9 slot

10 mounting holes

11 adapter plate

12 micro-switch

12a first micro-switch

12b second micro-switch

13 contact-switching movable part of micro-switch 12

14 motor

15 control module

16 door lock

17 gearwheel system

17a first gear wheel

17b second gear wheel

18 pin

19 batteries

20 positioning element

20a intendations

20b elevations

21 printed circuit board

22 diodes rear basis plate

' stabilizing structure on rear plate 23 slider plate

slider plate

rear plate

recess

switch base plate

screws

recess part