CLAMP ROLLER LOCK

Description

[0001] The invention relates to a clamping roller locking mechanism with a housing and at least two, preferably at least three clamping discs which are rotatably arranged in the housing and each have at least one recess in which a clamping roller is located, at least one drive projection and at least one output projection, wherein the clamping discs are arranged and designed in such a way that rotation of the clamping discs is possible by driving the drive projection and rotation of the clamping discs is prevented when driving the output projections.

[0002] Such a roller-type locking mechanism is known, for example, from DE 10 2006 046 495 A1. US 2002 / 0148696 A1 describes a special type of conventional freewheel in which rotation in one direction is possible and in the opposite direction is impossible. This is independent of whether the drive projections or the driven projections are driven.

[0003] Locking mechanisms and, in particular, roller-type locking mechanisms and other types of freewheels are used in a wide variety of applications, for example in orthopedic devices, when rotation of two components relative to each other should not be permitted in all directions or from all sides. For example, in upper extremity prostheses, the gripping, lifting, or rotating of end effectors is usually achieved using electric motors and corresponding gears. In most of these cases, the force applied once, for example a gripping force, should be maintained even after the power to the electric motor is switched off. However, this should be achieved without the need to maintain the power in order to save energy. This task is usually solved by a locking mechanism, which blocks the drive train from actuation by external forces.For some applications, this blocking is independent of the external force, while in others, a blockage should only be achieved in one direction of rotation. In upper extremity prostheses, these forces can be caused, for example, by holding an object or by the wearer of the orthopedic device, primarily the prosthesis, leaning on the gripping device. At the same time, however, it must be ensured that the drive train can run freely on the motor side. If it is driven by the motor, e.g. the electric motor, there should be no additional resistance to the movement of the end effector. The connection in an arm or hand prosthesis are just two examples of a whole range of possible applications, particularly in the field of orthopedic devices.Joints of orthoses, other components of orthoses or other prostheses can also be designed with corresponding clamping roller locks.

[0004] Hand prostheses are known from the prior art in which a wrap spring locking mechanism is used to achieve the desired locking of the drive train against actuation by external forces. In this case, the twisting of two spring ends causes a change in diameter and thus a frictional engagement of a stationary housing. This frictional engagement creates the desired locking effect. This can be implemented with a locking action on both sides or with free-running action on both sides. Other products and orthopedic devices often use simplified variations of roller locking mechanisms, which typically only lock in one direction of rotation and allow drive in the opposite direction.It is often irrelevant from which side the roller locking mechanism is driven, i.e. whether the acting force or torque is applied by a drive device, in particular the electric motor, or by an external force or torque.

[0005] GB 495 281 A discloses an artificial knee joint in which a drum brake is combined with a freewheel mechanism. This freewheel mechanism comprises a clamping roller lock with a clamping disc rotatably mounted in a housing. Rotation is possible in one direction, with clamping elements driven together with an inner element. Rotation in the opposite direction, however, activates the brake.

[0006] US 2002 / 148696 A1 relates to a freewheel clutch with a terminal housing constructed from rings pressed into one another in layers, in which an axle is rotatably mounted.

[0007] The invention is therefore based on the object of proposing a clamping roller locking mechanism which has the desired locking effects and at the same time is inexpensive, quick and easy to manufacture.

[0008] The invention solves the problem by a clamping roller locking mechanism according to claim 1.

[0009] The locking force can be scaled almost arbitrarily by changing the number of recesses and clamping rollers used.

[0010] Advantageously, at least one of the clamping rollers, but preferably all of the clamping rollers, extends through the recess of at least some, but preferably all of the clamping discs.

[0011] According to the invention, the recesses of the clamping discs are open radially outward and bounded on this side by the housing. They have a freewheel side large enough to prevent a clamping roller from coming into contact with the housing, and a locking side small enough to allow a clamping roller to come into contact with the housing.

[0012] The operating principle of a clamping roller locking mechanism has long been known in the art. At least one clamping roller is located in at least one recess, which is open radially outwards and delimited by the housing. If the clamping disc is now rotated, the clamping roller moves relative to the clamping disc within the recess. If it moves to the freewheeling side of the recess, it does not come into contact with the housing but can move freely on the freewheeling side of the recess. Rotation of the clamping disc relative to the housing is possible in this way. However, if the clamping roller moves to the locking side of the recess, it comes into contact with the housing on this side due to the small size of the recess and is clamped between the base of the recess, i.e. the clamping roller, and the housing, so that further rotation of the clamping disc relative to the housing is not possible.

[0013] According to the invention, for some of the clamping discs, the freewheel side is positioned clockwise in front of the locking side, and for another part of the locking discs, it is positioned clockwise behind the locking side. This distinguishes a corresponding roller-clamping locking mechanism from prior art roller-clamping locking mechanisms. These typically have only one clamping disc or a plurality of identical clamping discs, so that the freewheel side of all clamping discs, for example, is positioned clockwise exclusively in front of or exclusively behind the locking side.This allows the clamping discs in the housing to rotate in one direction when the rotation moves the clamping roller to the freewheel side of the recess. Rotation of the clamping discs in the housing in the opposite direction is blocked by the clamping roller, which moves to the locking side of the recess as a result of the movement and is thus clamped between the clamping disc and the housing. Simultaneous driving or blocking of all clamping discs is not possible with the clamping roller locks of this design described here.

[0014] In a preferred embodiment, by driving the drive projections in one direction of rotation, only those clamping discs are driven for which the freewheel side is located behind the locking side in the direction of rotation. For these clamping discs, this drive consequently moves the clamping roller into the freewheel side of the recess, so that rotation is not impaired by these clamping discs. However, since this is preferably only the case for some of the clamping discs, only this part of the clamping discs is driven. The other part of the clamping discs, for which the freewheel side is located in front of the locking side in the direction of rotation for the given direction of rotation, is not driven via the drive projections or the output projections, but is moved via the clamping roller, which in this case acts as a driver.The clamping roller for this section of the locking discs is located in the front part of the recess in the direction of rotation, which is the freewheel side for this section of the clamping discs. This ensures that rotation is always possible, regardless of the direction of rotation, as long as the drive is provided via the drive projections. The drive projections of the first section of the clamping discs are preferably arranged offset from the drive projections of the other section of the locking discs, so that a corresponding drive-side driver, which is coupled, for example, to an electric motor or other drive device, only reaches the desired drive projections and can drive the corresponding clamping discs.

[0015] Advantageously, by driving the output projections in one direction of rotation, only those clamping discs are driven for which the locking side lies behind the freewheeling direction in the direction of rotation. This drive and the corresponding movement of the locking discs move the clamping roller into the locking side of the recess, preventing further rotation because the clamping roller is clamped between the bottom of the recess and the housing. This also occurs independently of the direction of rotation, since depending on the direction of rotation, one or the other part of the locking discs is driven via the output projections. The output projections of the two parts of the clamping discs are therefore preferably arranged offset from one another.

[0016] It has proven advantageous if the clamping roller locking mechanism has an odd number of clamping discs and / or at least three recesses per clamping disc. At least one clamping roller is advantageously located in each of these at least three recesses. The more recesses and clamping rollers there are, the greater the locking force that can be achieved. In a particularly simple design of the clamping roller locking mechanism, the individual clamping discs are identical and are simply offset and, if necessary, rotated relative to one another. This reduces the number of different components required to construct the clamping roller locking mechanism.

[0017] In a preferred embodiment, the clamping discs are made of a metallic material. Alternatively or additionally, plastics, wood, wood-based materials, or other materials can also be used. They can be extruded, punched, laser-cut, water-jet cut, sawn, or injection-molded, for example.

[0018] The invention also achieves the stated object by means of an orthopaedic device having a drive device which is coupled to at least one drive-side driver, and an end effector which is coupled to an output-side driver, and having a clamping roller locking mechanism of the type described here, wherein the drive-side driver engages or can be brought into engagement with the drive projections and the output-side driver engages or can be brought into engagement with the output projections.

[0019] If the end effector is to be driven by the drive device, the drive-side driver is first set in rotation by the drive device. This driver is coupled to the drive projections, so that only those clamping discs are driven for which the freewheel side is located behind the locking side in the direction of rotation. This allows the clamping discs to rotate in the housing without additional resistance. This also drives the output-side driver, and the torque applied by the drive device is transferred to the end effector.

[0020] If, however, a torque or force is applied to the end effector from the outside, this torque or force is transferred to the output-side driver, which engages or can be brought into engagement with the output projections. However, when driving these output projections, only the part of the clamping discs for which the locking side is located behind the freewheel side in the direction of rotation is advantageously driven. This leads, as already explained, to a locking of the clamping roller locking mechanism.

[0021] An embodiment of the present invention is explained in more detail below with the aid of the accompanying drawings. It shows Figure 1 - a clamping disc for a clamping roller locking mechanism according to a first embodiment of the present invention, Figure 2 - a part of an orthopaedic device in an exploded view, Figure 3 - the top view of an output side of the device from Figure 2, Figure 4 - the top view of a drive side of the device from Figure 2 , Figure 5 - two detailed views of a clamping roller locking mechanism and Figure 6 - an orthopaedic device according to a further embodiment of the present invention in an exploded view.

[0022] Figure 1 shows a clamping disc 2 for a roller-clamping locking mechanism according to a first embodiment of the present invention. The clamping disc 2 has four recesses 4, which in the illustrated embodiment are distributed equidistantly around the circumference. Each of the recesses has a freewheel side 6 and a locking side 8. The recesses 4 open radially outward and are delimited by a housing when the roller-clamping locking mechanism is assembled.

[0023] Two projections 10 protrude radially inward, one side of which forms a drive projection 12 and the opposite side forms an output projection 14. Of course, the drive projection 12 and output projection 14 can also be separate projections.

[0024] Figure 2 shows an exploded view of a clamping roller locking mechanism according to an embodiment of the present invention with a drive-side driver 16 and a driven-side driver 18. The clamping roller locking mechanism has five clamping discs 2, each of which has four recesses 4, as shown in Figure 1 are shown. It contains four clamping rollers 20. The clamping discs 2 with the clamping rollers 20 are located in a housing 22 that radially delimits the recesses 4. In the illustrated embodiment, a cover disc 24 prevents the clamping rollers 20 from moving out of the recesses 4 in the axial direction.

[0025] Both the drive-side driver 16 and the output-side driver 18 have driver claws 26 with which they engage or can be brought into engagement with the drive projections 12 or the output projections 14.

[0026] You can already see in Figure 2 that the clamping discs 2 are arranged offset from one another, so that an angle between the projections 10 of two adjacent clamping discs 2 is 90° in the embodiment shown.

[0027] Figure 3 shows a top view of an output side of such a device. The output-side driver 18 with the two driver claws 26 and a clamping disc 2 with two projections 10 can be seen. The two driver claws 26 of the output-side driver 18 can be brought into engagement with the respective output projection 14 of the projections 10 by rotating the output-side driver 18.

[0028] In Figure 3 Two further projections 10 are also shown, which are located in Figure 3 right and left. These belong to a clamping disc 2, which is arranged behind the clamping disc 2 shown. These projections 10 also have output projections 14, with which the output-side driver 18 can be engaged via the driver claws 26.

[0029] The front clamping disc 2 shown has four recesses 4, each of which houses a clamping roller 20, which in the illustrated embodiment is located on the freewheel side 6. The recesses 4 of the additional locking disc 2 located behind the locking disc 2 are shown by a dashed line. The respective clamping roller 20 for these recesses 4 is also located on the freewheel side 6.

[0030] If, in the illustrated embodiment, the output-side driver 18 is set in rotation, the driver claws 26 engage either with the output projections 14 of the front clamping disc 2 or with the output projections 14 of the clamping disc 2 located behind it. If the output-side driver 18 is rotated counterclockwise, for example, its driver claws 26 engage with the output projections 14 of the frontmost clamping disc 2. This is consequently also rotated counterclockwise, whereby the clamping rollers 20 are moved in the respective recesses 4 to the respective locking side 8. This results in a locking of the clamping roller locking mechanism, since the clamping rollers 20 are clamped between the floor or the bottom of the recess 4 and the housing 22.

[0031] If, however, the output-side driver 18 is rotated clockwise, its driver claws 26 engage with the output projections 14 of the clamping disc behind it. This also moves clockwise, causing the clamping rollers 20 in the recesses 4 of this clamping disc 2 to move from the freewheel side 6 to the locking side 8, thus resulting in a locking action. Regardless of the direction in which the output-side driver 18 is subsequently moved, the clamping roller locking mechanism is always locked.

[0032] Figure 4shows a plan view of the drive side of such a clamping roller locking mechanism. The recesses 4 can be seen, each of which contains a clamping roller 20, although in the illustrated embodiment these are partially covered by the cover plate 24. The clamping rollers 20 are each located on the freewheel side 6 of the recess 4. The two driver claws 26 of the drive-side driver 16 are also shown. The two projections 10 shown on the right and left belong to the clamping disc 2 that is foremost in this direction, while the projections 10 shown above and below belong to the clamping disc located behind it. The projections 10 each have a drive projection 12 that can be brought into engagement with the respective driver claw 26.

[0033] If the drive-side driver 16 is moved with its driver claws 26 in a clockwise direction, the driver claws 26 come into contact with the drive projections 12 of the Figure 4The projections 10 shown on the right and left engage. This front clamping disc 2, to which these projections 10 belong, is also consequently moved clockwise, so that the clamping rollers 20 remain on the freewheel sides 6 of the recesses 4. Rotation is therefore possible.

[0034] However, if the drive-side driver 16 with its driver claws 26 is moved counterclockwise, the driver claws 26 come into contact with the drive projections 12 of the Figure 4 The projections shown above and below engage, which belong to the clamping disc located behind the clamping disc 2 shown. As shown in Figure 4 As shown, for this clamping disc 2, the locking side 8 of the recess 4 for this counterclockwise direction of rotation is located in front of the corresponding freewheel side 6, so that rotation of the clamping discs 2 relative to the housing 22 is also possible in this direction of rotation.

[0035] Regardless of the direction in which the drive-side driver 16 is rotated, rotation is therefore always possible.

[0036] This will be Figure 5 clearly. In the upper part of the Figure 5 A clamping roller 20 is shown, which is located in a recess 4 of the front clamping disc 2, with the recess 4 being represented by a solid line. For this recess 4, the locking side 8 is located on the right side of the recess 4, and the freewheel side 6, in which the clamping roller 20 is located, is located on the left side. For the clamping disc 2 located behind it, the recess 4 is also shown by a dashed line, but this time it is oriented the other way around. The freewheel side 6 is on the right, while the locking side 8 is on the left. A driver claw 26 of the output-side driver 18 can also be seen.

[0037] In the lower part of the Figure 5shows what happens when the front clamping disc 2 is rotated by the output-side driver 18 along the arrow 28, i.e. counterclockwise in the illustrated embodiment. The two recesses 4, which are again represented by the solid line for the frontmost clamping disc 2 and by the dashed line for the clamping disc behind it, move relative to one another, and the clamping roller 20 is moved to the right in the recess 4 of the frontmost clamping disc 2, i.e. in the direction of the locking side 8. As a result, it is clamped between the clamping disc 2 and the housing 22, and further rotation of the clamping disc 2 relative to the housing 22 is prevented.

[0038] Figure 6shows a schematic exploded view of a part of an orthopaedic device with a drive device 30, a drive-side driver 16, the clamping roller locking mechanism with the housing 22 and the clamping discs 2 arranged therein, as well as an output-side driver 18, which is coupled to an end effector 32 shown only schematically. List of reference symbols

[0039] 2Clamping disc 4Recess 6Freewheel side 8Locking side 10Protrusion 12Drive projection 14Output projection 16Drive-side driver 18Output-side driver 20Clamping roller 22Housing 24Cover disc 26Drive claw 28Arrow 30Drive device 32End effector

Claims

1. A jamming roller lock with a housing (22) and at least two, preferably at least three, clamping discs (2) which • are arranged in the housing (22) such that they can be rotated and • comprise at least one recess (4), in which a jamming roller (20) is situated, characterized in that the clamping discs comprise • at least one driving projection (12) and • at least one driven projection (14), wherein the clamping discs (2) are arranged and designed in such a way that a rotation of the clamping discs (2) is possible by driving the driving projections (12) and a rotation of the clamping discs (2) by driving the driven projections (14) is prevented wherein the recesses (4) of the clamping discs (2) are open radially outwards and are restricted by the housing (22) on this side, wherein they comprise a freewheel side (6), which is large enough to ensure that a jamming roller (20) does not come into contact with the housing (22), and a locking side (8), which is small enough to ensure that a jamming roller (20) comes into contact with the housing (22), wherein for one part of the clamping discs (2), the freewheel side (6) lies in front of the locking side (8) in the clockwise direction, and for the other part of the locking discs (2) it lies behind the locking side (8) in the clockwise direction.

2. The jamming roller lock according to claim 1, characterized by the fact that at least one, preferably all, jamming rollers (20) extend through recesses (4) of at least one, preferably all, clamping discs (2).

3. The jamming roller lock according to claim 1 or 2, characterized by the fact that, by driving the driving projections (12) in one direction of rotation, only those clamping discs (2) are driven for which the freewheel side (6) lies behind the locking side (8) in the direction of rotation.

4. The jamming roller lock according to claim 1, 2 or 3, characterized by the fact that, by driving the driven projections (14) in one direction of rotation, only those clamping discs (2) are driven for which the locking side (8) lies behind the freewheel side (6) in the direction of rotation.

5. The jamming roller lock according to one of the above claims, characterized by the fact that the jamming roller lock comprises an uneven number of clamping discs (2) and / or at least three recesses (4) per clamping disc (2).

6. The jamming roller lock according to one of the above claims, characterized by the fact that the clamping discs (2) have the same contour.

7. The jamming roller lock according to one of the above claims, characterized by the fact that the clamping discs (2) are made of a metallic material and / or a ceramic material.

8. An orthopedic device with a driving device (30), which is coupled with at least one driver on the driving side (16), and an end effector (21), which is coupled with a driver on the driven side (18), and a jamming roller lock according to one of the preceding claims, wherein the driver on the driving side (16) is or can be engaged with the driving projections (12) and the driver on the driven side (18) is or can be engaged with the driven projections (14).