THREAD CLEANER

TECHNICAL FIELD

The present invention relates to a cleaning device for cleaning threads on e.g. a bolt or the like. This cleaning device is especially advantageous for the removal of dirt in long threaded pins or bolts, but is also well adapted to be used on any threaded device.

BACKGROUND ART

Threaded devices, such as bolts or threaded shanks provided with an external/male thread, used in dirty surroundings may pick up dirt in the thread grooves. This will obstruct a proper function of the threaded part, since a threaded counterpart, such as a nut, will be prevented to be screwed on to the threaded device. The nut will be exposed to greater friction which prevents the nut to be mounted in the normal way with the normal force. In some cases, the nut may even get stuck which in turn may cause damage to either one or both of the threaded parts.

The contamination of the thread may also be caused by paint, rust protection means, dried out grease or rust. For example, a machine or the like is assembled in a plant. After the assembly, parts of the machine may be coated with e.g. paint, grease or different types of rust inhibitors to protect the machine to environmental influences. This will cause a problem when the machine is to be repaired or maintained, since the coating will also hinder e.g. a nut to be removed from or replaced to a threaded part.

To solve this problem, different solutions have been proposed.

WO 2005/084863 A1 and WO 2005/084864 discloses a hand operated tool for repairing damaged treads of a screw. The tool is adjustable to different thread dimensions. The tool is usable when a thread has a minor damage in the form of a nick or another smaller deformation. The tool is

positioned over the thread and adjusted to accommodate the screw. A cutting blade will, when the tool or screw is rotated, restore the thread.

GB 2393771 A discloses a cleaning device for removing debris from the thread of a threaded member such as a bolt. The device is a nut provided with a toothed portion that projects into the tread and expels debris when the nut is rotated on the thread. The cleaning device is adapted for one fixed thread dimension.

US 6206620 B1 discloses a pivoting split thread chasing die. The die can be used for the rethreading and cleaning of damaged or inhibited studs or bolts. The die is adapted for one fixed thread dimension.

US 6023807 discloses a cleaning device with a plurality of adjustable brushes.

None of the above documents discloses a thread cleaner that is adapted for the cleaning of threads of different dimensions in an easy way.

DISCLOSURE OF INVENTION

An object of the invention is therefore to provide a cleaning device for cleaning threads that is adjustable and easy to mount on a threaded part.

Another object of the invention is to provide an improved cleaning device that provides a fast cleaning action. A further object of the invention is to provide an improved cleaning device that provides less wear of the cutting teeth. A further object of the invention is also to provide a cleaning device that is adapted to be used in a nut runner.

The solution to this problem according to the invention is described in the characterizing part of claim 1. The other claims contain advantageous embodiments and further developments of the gripping device according to the invention.

With a cleaning device for the cleaning of a threaded part, comprising a first body portion comprising at least one adjustable cutter and a second body portion comprising at least one adjustable member, the object of the invention is achieved in that the at least one adjustable cutter of the first body portion and the at least one adjustable member of the second body portion are adjustable with the same adjustment screw.

By this first embodiment of the gripping device according to the invention, a cleaning device is obtained which can be adjusted to accommodate threads of different sizes in an easy way, since both the cutter(s) and the adjustable member are adjusted at the same time with the same adjustment screw. This obviates the need of having a plurality of different sized cleaning devices in a workshop. In this first embodiment, the adjustable member of the second body portion is a bearing surface, against which the threaded part will bear during the cleaning action. The threaded part will be clamped between the cutters and the bearing surface. Since both the cutters and the bearing surface are adjusted at the same time with the same adjustment screw, the threaded part will be centred in the cleaning device, which will improve the cleaning process.

In an advantageous further development of the cleaning device according to the invention, the adjustable member of the second body portion is also a cutter. The threaded part will in this case be clamped between the cutters of the first body portion and the cutters of the second body portion.

Since the cutters are adjusted at the same time with the same adjustment screw, the threaded part will be centred in the cleaning device, which will improve the cleaning process.

In an advantageous further development of the cleaning device according to the invention, the adjustment screw connects the first body portion with the second body portion. This allows for a simplified cleaning device.

In an advantageous further development of the cleaning device according to the invention, the first body portion and the second body portion are pivotably connected to the adjustment screw. This allows for a splitable cleaning device, which facilitates the mounting of the cleaning device to a threaded part. This is especially advantageous when long threaded parts are to be cleaned.

In an advantageous further development of the cleaning device according to the invention, each body portion of the cleaning device is provided with a plurality of cutters. This allows for a faster and more precise cleaning action. The wear of each cutter will also be reduced.

In an advantageous further development of the cleaning device according to the invention, the cutters and the body portions are suspended on the same axle. This is advantageous in that the cleaning device can be opened and closed without the need to readjust the cleaning device.

In an advantageous further development of the cleaning device according to the invention, the cutters of the cleaning device are resiliently suspended. This allows for a smoother handling of the device and will lessen the wear of the cutters, since irregularities of a threaded part can be compensated for.

In an advantageous further development of the cleaning device according to the invention, the cutters of the cleaning device are adjustable between a first inner operation mode and a second outer operation mode. By this, a range of different sized threaded parts can be cleaned by one cleaning device.

In an advantageous further development of the cleaning device according to the invention, the cutters of the cleaning device are provided with teeth. This allows for an improved cleaning action.

In an advantageous further development of the cleaning device according to the invention, the angle of the cutter surface is perpendicular to the centre of the cleaning device when the cutters are adjusted to the middle of the adjustment range. In this way, a good cleaning action is guaranteed for all threaded parts in the cleaning range, for which the cleaning device is adapted.

In an advantageous further development of the cleaning device according to the invention, the cutter surface is provided with a radius. This is advantageous in that the cleaning device can be especially adapted to a specific thread size, but still be able to clean all thread sizes in the adjustment range.

In an advantageous further development of the cleaning device according to the invention, at least one body portion is provided with at least one magnet. In this way, the handling of the cleaning device will be facilitated.

In an advantageous further development of the cleaning device according to the invention, the outer surface of the cleaning device is provided with at least one protrusion, which may be resilient. In this way, the cleaning device can be kept in place when mounted to a driving tool.

In an advantageous further development of the cleaning device according to the invention, the cleaning device is adapted to be mounted in a nut runner. This is advantageous in that nut runner tools may already be available in e.g. a work shop. No special driving tools are thus required.

The invention also discloses a nut runner comprising an inventive cleaning device.

BRIEF DESCRIPTION OF DRAWINGS

The invention will be described in greater detail in the following, with reference to the embodiments that are shown in the attached drawings, in which

Fig. 1 shows a cleaning device according to the invention,

Fig. 2 shows a view of a body portion of the cleaning device according to the invention,

Fig. 3 shows a side view of the cleaning device according to the invention in a first operation mode,

Fig. 4 shows a side view of the cleaning device according to the invention in a second operation mode,

Fig. 5 shows the cleaning device according to the invention when mounted in a nut runner.

MODES FOR CARRYING OUT THE INVENTION

The embodiments of the invention with further developments described in the following are to be regarded only as examples and are in no way to limit the scope of the protection provided by the patent claims.

Fig. 1 shows a first embodiment of the inventive cleaning device. The cleaning device 1 comprises a first body portion 2 and a second body portion 3 connected to each other by an adjustment screw 4. The adjustment screw 4 is provided with two sections, each section covering substantially half of the length of the screw. The first section is provided with an external right-hand thread and the second section is provided with an external left-hand thread. The first body portion 2 comprises a first axle 5 and the second body portion 3 comprises a second axle 6. The first axle 5 is provided with an internal right-hand thread and the second axle 6 is provided with an internal left-hand thread.

The adjustment screw 4 runs through the internal threads of the first axle 5 and the second axle 6, with the right-hand thread of the first section running in the internal right-hand thread of the first axle 5 and the left-hand thread of the second section running in the internal left-hand thread of the

second axle 6. When adjustment screw 4 is rotated, the first axle 5 and the second axle 6 will move in opposite directions along the length of the adjustment screw 4. This action, as will be described below, is used to adjust the cleaning device.

The adjustment screw 4 is provided with a headed screw in each end. This is preferably a hexagonal socket cap screw, i.e. a headed screw with an internal hexagonal key grip. These screws are inserted after the axles 5, 6 have been mounted to the adjustment screw 4, and will function both as an end stop for the axles 5, 6 and also as a key grip when adjusting the cleaning device.

The body portions 2, 3 are in a preferred embodiment uniform to each other, except for the direction of the thread in axles 5 and 6. Thus, only body portion 2 will be described closer.

Body portion 2, shown in fig. 2, comprises a first arm cover 7 and a second arm cover 8 connected to each other by an intermediate member

9. The first arm cover 7 is at one side provided with an elongated opening

10. The first arm cover is mounted to axle 5 through the elongated opening 10 using a screw. The second arm cover is mounted to axle 5 in the same way. The body portion is further provided with a first cutter 11 and a second cutter 12. The cutters 11 and 12 are in a preferred embodiment uniform to each other. The second body portion 3 is in this example provided with a third cutter 20 and a fourth cutter 21. The third cutter 20 and the fourth cutter 21 are in this example identical to the first cutter 11 and the second cutter 12.

Each cutter is at one end mounted onto axle 5 through an opening in the cutter. Each cutter is mounted between the arm covers 7, 8 and the adjustment screw 4. Each cutter is further provided with an elongated opening 13 in the mid-section of the cutter. The elongated opening 13 is adapted to run on a pin 14, which connects the arm cover and the

intermediate member. Each cutter 11 and 12 (and 20, 21) is mounted in the same way. The elongated openings in the arm covers and the elongated openings in the cutters are parallel to one another and to plane

16 (shown in Fig. 3). At the same time, the elongated openings in the arm covers and the elongated openings in the cutters are perpendicular to a plane 15 (shown in Fig. 3) of the device. Plane 15 is the plane around which the device can be opened, i.e. the splitting line of the device.

The cutters are thus arranged so that they can move along plane 16 in a parallel way when the adjustment screw 4 is rotated. The cleaning device can in this way be adjusted to accommodate threaded parts with different diameters. The adjustment range is set by the length of the adjustment screw 4 and the length of the elongated openings. In one embodiment, it is possible to use different sets of cutters in order to set the adjustment range for the cleaning device. The height of the cutter, i.e. the dimension along plane 16, can thus be varied such that different ranges of threaded parts can be cleaned by the device.

Fig. 3 shows the cleaning device adjusted to a first operation mode, i.e. when the cutters are adjusted to the innermost position for that specific cutter. In this first operation mode, the cleaning device is set to clean the thinnest of threaded parts possible for this adjustment range.

Fig. 4 shows the cleaning device adjusted to a second operation mode, i.e. when the cutters are adjusted to the outermost position for that specific cutter. In this second operation mode, the cleaning device is set to clean the thickest of threaded parts possible for this adjustment range. Since the device is variable and can be adjusted steplessly, it can be set to any dimension in the adjustment range between the first and second operation mode.

The cutters 11 , 12 are in a first embodiment provided with cleaning teeth

17 on the cutter surface 22 facing inwards towards the centre of the

cleaning device when mounted. The angle α of the cutter surface 22 is preferably selected such that the midsection of the cutter surface points toward i.e. is perpendicular to, the centre of the cleaning device when the cutters are adjusted to the middle of the adjustment range. In this way, at least some teeth will bear on the thread that is to be cleaned over the complete adjustment range. The angle of inclination of a cleaning tooth 24 may be selected as desired and may be different for each side of the tooth. It is advantageous to let the teeth be symmetrical with respect to plane 16. In this way, the cleaning action of the cleaning device will be the same regardless of the operating direction, i.e. regardless of in which direction the cleaning device is moved with respect to the threaded part.

It is advantageous to let the teeth be pointed sideways, i.e. laterally, with an angle that resembles that of the thread groove that is to be cleaned. The angle may be slightly larger than the angle of the thread in order to allow for as much dirt removal as possible in the outer part of the thread. With the teeth pointed with an angle slightly smaller than the thread angle, the inner part of the thread will be reached completely by the teeth. It is also possible to provide the cutter surface 22 with other types of shapes, e.g. serrated, wavy or straight. It is advantageous to use a cutter with only one row of teeth adapted to fit one thread groove. For a cleaning device that is adjustable only over a small range, e.g. for two or three tread sizes or for a metric thread and an imperial thread, it is also possible to provide two or more teethed rows beside each other, in order to improve the cleaning action. The width of a cutter is relatively thin and is preferably in the same order as the pitch of the thread.

The outer shape of the cleaning device is in one embodiment hexagonal. This means that each arm cover 7, 8 are provided with three 60-degree angles. In this way, the cleaning device resembles a hexagon nut and can be used together with a tool having a hexagonal opening, such as a wrench or a nut runner. The outer surface of the cleaning device may be

provided with one or more protrusions 19, e.g. in the form of a spring- loaded pressure screw or a resilient member. This protrusion may be adapted to fit a recess in a nut driver, allowing a hold of the cleaning device in e.g. a nut runner. In Fig. 5, an example of the cleaning device of the invention is shown when positioned in a nut runner 23. If the cleaning device is to be rotated in another way, e.g. by hand, it is also possible to give the cleaning device another outer shape, e.g. a more rounded shape.

The cleaning device can be mounted to the threaded part that is to be cleaned in two different ways. If the threaded part is short, such as e.g. a bolt, or if the threaded part is to be cleaned from its free end, the cleaning device can be mounted to the threaded part in the same way as a nut, i.e. the cleaning device is rotated onto the free end of the threaded part.

If the thread is to be cleaned from the inside and out, e.g. from the head of a bolt in the direction to its free end, the cleaning device can be opened in the horizontal plane 15 by moving the first body portion 2 and the second body portion 3 away from each other. The first axle 5 and the second axle 6 will function as hinges, so that the first body portion will rotate around the first axle 5 and the second body portion will rotate around the second axle 6. This is possible since the outer bodies and the cutters have the same rotational centre, i.e. the axles. The cleaning device is thus opened, and the device is closed around the threaded part. The intermediate member 9 of the first body portion and the intermediate member of the second body portion may be provided with one or more magnets 18 to keep the cleaning device closed. This will improve the handling of the cleaning device. Other closing devices, such as locking pins, hooks, clips etc can be used to keep the cleaning device closed.

When the cleaning device is mounted around the threaded part that is to be cleaned, the cutters are adjusted to the appropriate cleaning position by turning the adjustment screw 4. This may be done with a hexagonal wrench fitting the end screw inserted into adjustment screw 4. When the

cleaning device is appropriately adjusted, the cleaning device may either be rotated using e.g. a wrench, a spanner or the like, or it may be inserted into a nut runner that is inserted along the threaded part. When the cleaning device is inserted into the nut runner, the nut runner is powered by an appropriate means, e.g. a power tool such as an electric or pneumatic screw driver.

The cleaning device is thus driven along the threaded part and the teeth of the cutters runs in the thread, thereby removing dirt, rust, paint etc from the thread. Since the cleaning device is of an open internal design, the removed particles will have plenty of room to dispose in without clogging the cleaning device. When the cleaning device is mounted in a driving device, the removed particles will be collected inside the cleaning device for later disposal, which may be advantageous for environmental reasons.

The cleaning device comprises in one embodiment two cutters in each body portion. The distance between the two cutters is preferably adapted to a multiple of the pitch of the thread that is to be cleaned. Since different diameters of a thread may have different thread pitches, the cutters are preferably somewhat resilient suspended. This may be done by applying resilient means such as O-rings to both sides of the cutters during mounting. The resilient means will allow the cutters to flex somewhat sideways, allowing the cutter teeth of both cutters to enter two different thread grooves in the threaded part. The resilient means may also allow the cutters to flex somewhat away from the threaded part. This makes it possible to apply a slight pretension on the cutters in respect to the threaded part. This will also allow the cutters to move somewhat if the thread is slightly damaged, which will avoid damage to the cleaning device.

In a second embodiment of the invention, the cutter surface 22 is provided with a continuous radius surface instead of on two angled portions. The radius of the surface, and thus of the teeth, is preferably selected such

that the radius corresponds to a threaded part when the cutters are adjusted to the middle of the adjustment range. In this way, at least some teeth will bear on the thread that is to be cleaned over the complete adjustment range. This embodiment is advantageous when the cleaning device is mainly used to clean one specific thread dimension, but where occasional cleaning of other dimensions may occur.

In a third embodiment of the invention, the second body portion is provided with an adjustable member acting as a bearing surface instead of the cutters 20 and 21. The bearing surface may either be provided with the same angle as the cutter surface 22 or may be provided with a radius. The bearing surface may have the width of the cleaning device or may be slightly narrower. The bearing surface is preferably of a hard material in order to reduce friction when it bears on the crests of the thread of the threaded part. Since the bearing surface will be adjusted at the same time as the cutters, the threaded part will always be centred in the cleaning device, which in turn improves the cleaning procedure. This embodiment may be advantageous to reduce friction when using the cleaning device manually.

One further advantage of the inventive cleaning device compared to a cleaning device with a single, fixed cleaning dimension is that when the inventive cleaning device wears somewhat, the cutters can be adjusted to bear against the thread. In this case, the cleaning device can be used for a longer time without the need to replace the cutters or the complete cleaning device.

The invention is not to be regarded as being limited to the embodiments described above, a number of additional variants and modifications being possible within the scope of the subsequent patent claims. The cleaning device can, for example, also be provided with another number of cutters and the cutters may have different shapes and different types of teeth.

REFERENCE SIGNS

1 : Cleaning device

2: First body portion

3: Second body portion

4: Adjustment screw

5: First axle

6: Second axle

7: First arm cover

8: Second arm cover

9: Intermediate member

10: Elongated opening

11 : First cutter

12: Second cutter

13: Elongated opening

14: Pin

15: Horizontal plane

16: Vertical plane

17: Cleaning teeth

18: Magnet

19: Protrusion

20: Third cutter

21 : Fourth cutter

22: Cutter surface

23: Nut runner

24: Cleaning tooth