DEVICE FOR STABILISING JOINTS

Abstract

The present invention relates to a device (1) for stabilising joints, comprising a receptacle (20), wherein the receptacle (20) is filled with a filling medium (30), a first body (40) for interaction with the filling medium (30), wherein the first body is arranged displaceably in the receptacle (20), a force-transmission means (50) for the transmission of an external force onto the first body (40), a second body (60) for interaction with the filling medium (30) which is arranged displaceably in the receptacle (20), wherein the second body is coupled elastically to the first body (40) via a coupling element (70), wherein at least one of the second body (60) and the first body (40) have at least one outlet opening (64) through which the filling medium (30) can flow, and wherein the first body (40) forms a valve body and the second body (60) forms a valve seat so that a flow of the filling medium (30) through the outlet opening (64) can be allowed or prevented as a function of the valve position.

Claims

1. Device for stabilising joints, comprising: a receptacle, wherein the receptacle is filled with a filling medium, a first body for interaction with the filling medium, wherein the first body is arranged displaceably in the receptacle, a force-transmission means for the transmission of an external force onto the first body, wherein a second body for interaction with the filling medium, which second body is arranged displaceably in the receptacle, wherein the second body is coupled elastically to the first body via a coupling element, wherein at least one of the second body and the first body have at least one outlet opening through which the filling medium can flow, and wherein the first body forms a valve body and the second body forms a valve seat so that a flow of the filling medium through the outlet opening can be allowed or prevented as a function of the valve position.

2. Device according to claim 1, characterised in that the shear surface of the first body and the shear surface of the second body have a different size.

3. Device according to claim 1, characterised in that the shear surface of the first body is smaller than the shear surface of the second body.

4. Device according to claim 1, characterised in that a gap dimension between the first body and the receptacle is different from a gap dimension between the second body and the receptacle.

5. Device according to claim 1, characterised in that the gap dimension between the first body and the receptacle is larger than the gap dimension between the second body and the receptacle.

6. Device according to claim 1, characterised in that the coupling element comprises at least one spring element.

7. Device according to claim 1, characterised in that the coupling element is manufactured from a material with a temperature-dependent modulus of elasticity.

8. Device according to claim 1, characterised in that the outlet opening can be closed by means of the first body and/or the second body so that a flow of the filling medium through the outlet opening can be prevented.

9. Device according to claim 1, characterised in that the force-transmission means for transmission of the external force is formed in one piece with the first body.

10. Device according to claim 1, characterised in that the first body can exert a compressive force and/or a tractive force on the second body by means of coupling element.

11. Device according to claim 1, characterised in that the size of the shear surface of the first body, and the size of the shear surface of the second body are configured in such a manner that, if the external force acts with a speed below a threshold value on the first body, the first body and the second body can be moved almost uniformly through the filling medium, and that, if the external force acts with a speed greater than or equal to the threshold value on the first body, the first body and the second body can be moved relative to one another.

12. Device according to claim 1, characterised in that the filling medium is a fluid.

13. Device according to claim 1, characterised in that the filling medium is shear-thickening.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0042] Further embodiments and aspects of the present invention will be explained in greater detail by the following description of the figures. In the figures:

[0043] FIG. 1A shows a perspective view of a device for stabilising joints,

[0044] FIG. 1B shows a perspective sectional view of the device from FIG. 1A in an initial state,

[0045] FIG. 1C shows a sectional view of the device from FIG. 1A in an initial state,

[0046] FIG. 2A shows a perspective sectional view of the device from FIG. 1A in a holding state,

[0047] FIG. 2B shows a sectional view of the device from FIG. 1A in a holding state,

[0048] FIG. 3A shows a sectional view of the device from FIG. 1A along sectional line A-A from FIG. 2B,

[0049] FIG. 3B shows a sectional view of the device from FIG. 1A along sectional line C-C from FIG. 2B,

[0050] FIG. 4A shows a perspective view of the first body and of the second body in an initial state,

[0051] FIG. 4B shows a perspective view of the first body and of the second body in a compressed state,

[0052] FIG. 5 shows a schematic sectional view of a device for stabilisation of joints, wherein the bodies have gap dimensions of different sizes,

[0053] FIG. 6 shows a schematic sectional view of a device for stabilisation of joints, wherein the bodies have shear surfaces of different sizes,

[0054] FIG. 7 shows a schematic sectional view of a device for stabilisation of joints, wherein the receptacle has a step, and

[0055] FIG. 8 shows a schematic sectional view of a device for stabilisation of joints, wherein the receptacle has a conical form.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0056] A perspective view of a device 1 for stabilising joints can be inferred from FIG. 1A. A force-transmission means 50 protrudes out of a cylindrical receptacle 20. In this case, the receptacle can be fastened to a body part of a user and force-transmission means 50 to a different body part of the user. Direction B represents the direction of movement of the device. Alternatively, the receptacle can also be formed to be quadratic.

[0057] The interior of device 1, which is in an initial state, can be inferred from FIGS. 1B and 1C. Device 1 comprises a receptacle 20 which can be fastened to a region of the body of a user. Receptacle 20 20 has an opening 22 through which a force-transmission means 50 projects into the inner space of device 20. The end of force-transmission means 50, which lies outside device 20, can be fastened to a different region of the body of the user.

[0058] If the body region of the user to which receptacle 20 is fastened moves relative to the body region of the user on which force-transmission means 50 is arranged, force-transmission means 50 moves relative to receptacle 20. In particular, force-transmission means 50 can move in a main direction of movement B further into receptacle 20 or further out of receptacle 20. The receptacle of the device is manufactured from plastic. Among other things, fibre-reinforced plastics can also be used. Alternatively, the receptacle can also be manufactured from metals such as, for example, aluminium or magnesium. Moreover, the receptacle can also be manufactured from ceramic. Force-transmission means 50 is a rod element made of plastic. Alternatively, the force-transmission means can also be formed to be fibrous. Moreover, the force-transmission means can also be manufactured from metal such as, for example, aluminium, magnesium or steel.

[0059] The inner space of device 20 is filled with a filling medium 30. Filling medium 30 is a dilatant fluid. Alternatively, Newtonian fluids such as, for example, silicon oil can be used as filling medium. Moreover, a shear-thickening plastic can also be used. The plastic is present in this case in powder form. Moreover, sand can also be used as the medium.

[0060] Furthermore, a first body 40 is arranged in inner space 24 of device 20 and is movable in direction of movement B relative to receptacle 20 through filling medium 30. First body 40 is coupled at a force-transmission region 44 to the force-transmission means 50 so that a force proceeding from force-transmission means 50 can be transmitted to first body 40.

[0061] The surface of first body 40, relative to which the filling medium flows if first body 40 is moved in direction of movement B, forms a shear surface 42. An increase in shear stress arises in the region of shear surface 42 as a result of the filling medium if first body 40 is moved with a non-physiological speed through the filling medium.

[0062] A gap dimension S1 represents the minimal distance between shear surface 42 of first body 40 and inner surface 26 of the receptacle. First body 40 is manufactured from plastic. Alternatively, the first body can also be manufactured from a metal such as, for example, aluminium.

[0063] A second body 60 which is movable relative to receptacle 20 in direction of movement B is furthermore arranged in inner space 24 of receptacle 20. The outer circumferential surface of second body 60 forms a shear surface 62. Second body 60 comprises guide projections 66 which can contact the inner space of receptacle 20 in a punctiform manner in order to movably guide second body 60 in inner space 24 of receptacle 20.

[0064] The smallest distance between shear surface 62 and inner surface 26 of receptacle 20 forms gap dimension S2. Second body 60 is manufactured from plastic. Alternatively, the second body can also be manufactured from a metal such as, for example, aluminium.

[0065] First body 40 is coupled to second body 60 via an elastic coupling element 70. Elastic coupling element 70 shown in FIGS. 1B and 1C is formed by a spring which is mounted at one end in a spring seat 46 of first body 40 and at the other end in a spring seat 68 of second body 60. According to the direction of movement B in which a force acts on force-transmission means 50, second body 60 can be pulled or pushed via coupling element 70 by means of first body 40. In this case, the spring can be manufactured from plastic or from metal. Alternatively, elastic coupling element 70 can also be formed in the form of an elastic polymer or rubber.

[0066] In one further alternative, the first body, the second body and the elastic coupling element are injection moulded in one piece.

[0067] Second body 60 furthermore comprises an outlet opening 64 through which filling medium 30 can flow. If second body 60 is correspondingly moved by a force proceeding from coupling element 70 relative to receptacle 20, shear-thickening medium 30 can flow both externally in the region of gag dimension S2 and internally through outlet opening 64 along the second body.

[0068] Device 1 shown in FIGS. 1A to 1C is designed for tensile loads. I.e. also loads which result from a moving away from one another of the body region of the user to which receptacle 20 is fastened and of the body region of the user to which force-transmission means 50 is fastened. If force-transmission means 50 is pulled out of device 20, it pulls second body 40 with it, as a result of which the latter pushes onto second body 60 by means of coupling element 70. Force-transmission means 50 is embodied to be rod-shaped and extends from first body 40 through outlet opening 64 of second body 60 and finally through opening 22 of receptacle 20. Sealing means, which are not represented in FIGS. 1A and 1B and seal off inner space 24 of receptacle 20 from the surroundings, are arranged in the region of opening 22 so that filling medium 30 can be kept in inner space 24 of receptacle 20.

[0069] The function of the device is described below on the basis of FIGS. 1B to 2B. If a force acts in the range of a physiological speed on force-transmission means 50 so that first body 40 is pulled in the direction of opening 22, second body 60 is also pushed by means of coupling element 70 in the direction of opening 22. Depending on the size of shear surface 62 and/or gap dimension S2, a threshold valve can be defined which specifies a speed of the second body in the case of which an increase in shear stress arises as a result of the flow of filling medium 30 along shear surface 62 which does not allow any further movement of second body 60. This threshold value can furthermore be influenced by the properties of elastic coupling element 70. In the case of coupling element 70 shown in FIGS. 1A and 1B in the form of a spring, a standstill of second body 60 comes about if the resultant holding force generated in the region of shear surface 62 is greater than or equal to a spring force proceeding from the spring.

[0070] Once second body 60 has been blocked as a result of the shear hardening in the region of shear surface 62, the force acting on force-transmission means 50 moves second body 40 furthermore in the direction of opening 22. In this case, filling medium 30 can flow along shear surface 42 of first body 40 and through outlet opening 64 of second body 60. The further first body 40 moves towards opening 22, the smaller the distance between first body 40 and second body 60. Second body 40 can moved in the direction of opening 22 for so long until the distance between first body 40 and second body 60 is closed, as shown in FIGS. 2A and 2B.

[0071] In the state of device 1 shown in FIGS. 2A and 2B, first body 40 contacts second body 60 in such a manner that outlet opening 64 of second body 60 is closed. It is now only in the region between shear surfaces 42, 62 of first and of second body 40, 60 and of inner surface 26 that filling medium 30 located in inner space 24 has the possibility of flowing relative to first body 40 and second body 60 in so far as the degree of shear hardening allows.

[0072] In order to move first body 40 and second body 60 in the direction of opening 22, a holding force which results from the interaction of a sum of shear surface 42 and shear surface 62 with filling medium 30 must now be overcome. Device 1 is correspondingly able to provide a significantly larger holding force after closing outlet opening 64. In device 1 shown in FIGS. 1A, 1B, 1C, 2A and 2B, the speed-dependent resistance of device 1 against pulling out of force-transmission means 50 increases with the closing of outlet opening 64 by a factor of 50. Device 1 can correspondingly be dimensioned in such a manner that, in the case of an open outlet opening 64, a physiological force outlay of 20 N is necessary in order to move first body 40 relative to receptacle 20 and in the case of closed outlet opening 64 a force outlay of 1000 N is necessary in order to move first body 40 and second body 60 in the state lying next to one another relative to receptacle 20.

[0073] FIG. 3A shows a sectional view along sectional line A-A from FIG. 2B. It can be inferred from FIG. 3A that guide projections 66 guide second body 60 along inner surface 26 of receptacle 20. Gap dimension S1 which represents the smallest distance between shear surface 42 and inner surface 26 and gap dimension S2 which represents the smallest distance between shear surface 62 and inner surface 26 can furthermore be inferred from FIG. 3A.

[0074] FIG. 3B is a sectional view along sectional line C-C from FIG. 2B, from which outlet opening 64 in second body 60 can be inferred. FIG. 3B furthermore shows a concentric arrangement of force-transmission means 50 which extends through outlet opening 64 without touching second body 60.

[0075] FIG. 4A shows a perspective view of first body 40, coupling element 70 and second body 60 in the state shown in FIG. 1.

[0076] FIG. 4B shows a perspective view of first body 40, coupling element 70 and second body 60 in the state shown in FIG. 2.

[0077] FIG. 5 schematically shows a device 1 which is suitable for pressure loading. Force-transmission means 50 is connected to first body 40 in one piece and protrudes through opening 22 out of receptacle 20. If force-transmission means 50 is pushed into receptacle 20, first body 40 and second body 60 move away from opening 22. If the speed at which first body 40 moves away from opening 22 lies in the physiological range, second body 60 is pushed via coupling element 70 away from opening 22.

[0078] Second body 60 possesses a gap dimension S2 which is smaller than gap dimension S1 of first body 40. Moreover, shear surface 62 of second body 60 is larger than shear surface 42 of first body 40.

[0079] The ratio of the shear surfaces and the ratio of the gap dimensions of first body 40 and of second body 60 allows an increase in shear stress to occur in the region of shear surface 62 in the case of a speed in direction of movement B, in the case of which no or a significantly lower increase in shear stress occurs at shear surface 42. As a result, it is possible that second body 60 is blocked by the holding force, which is a result of the increase in shear stress, when a critical speed in direction of movement B is reached. In this situation, the holding force acting on second body 60 is greater than or equal to the opposite elastic force proceeding from coupling element 70.

[0080] If second body 60 is blocked as a result of the increase in shear stress in the region of shear surface 62 and if first body 40 is furthermore moved away from opening 22, the distance between first body 40 and second body 60 is reduced. In this state, the critical speed of first body 40 is defined by the size of shear surface 42 and gap dimension S1.

[0081] If the distance between first body 40 and second body 60 is closed by an ongoing force acting on force-transmission means 50, the critical speed at which an increase in shear stress occurs is defined by the sum of shear surfaces 42 and 62. A significantly larger holding force or resistance force acts counter to the compressive force acting on force-transmission means 50 after closing of the distance between first body 40 and second body 60.

[0082] Device 1 shown in FIG. 6 differs from the device shown in FIG. 5 in that gap dimension S1 between first body 40 and inner surface 26 is equal to gap dimension S2 between second body 60 and inner surface 26. Moreover, shear surface 62 of first body 40 is significantly larger than shear surface 42 of first body 40.

[0083] As a result, the speed in direction of movement B at which second body 60 is blocked as a result of the increase in shear stress of filling medium 30 in the region of shear surface 62 is lower than the speed in direction of movement B at which first body 40 is blocked as a result of the increase in shear stress of filling medium 30 in the region of shear surface 42.

[0084] Device 1 shown in FIG. 6 behaves like the device shown in FIG. 5 in the case of compressive loading of the force-transmission means into the interior of receptacle 20.

[0085] FIG. 7 shows a simplified representation of receptacle 20 and first body 40 arranged therein which is connected via coupling element 70 to second body 60. The profile of receptacle 20 has a step 28 by which receptacle 20 in a region with a large diameter and a region with a small diameter is defined. For the sake of simplicity, the force-transmission means is not represented in FIG. 7. However, FIG. 7 shows an arrow which represents an external force F which points in the direction of the region of the receptacle with a smaller diameter. First body 40 and second body 60 have the same dimensions. Alternatively, the dimensions can also vary as shown in FIGS. 5 and 6. First body 40 and second body 60 are arranged in such a manner that, in the case of a movement in direction of movement B towards the region of receptacle 20 with the smaller diameter, second body 60 reaches this region before first body 40.

[0086] If first body 40 and second body 60 move through the region of receptacle 20 with the larger diameter, both bodies are spaced apart by gap dimension S1 from inner surface 26 of receptacle 20. If second body 60 reaches the region of receptacle 20 with the smaller diameter, second body 60 is now only spaced apart by gap dimension S2 from inner surface 26 of receptacle 20. As is apparent from FIG. 7, gap dimension S2 is smaller than gap dimension S1. By reaching the region of receptacle 20 with the smaller diameter, as represented in FIG. 7, the speed reduces at which second body 60 is blocked as a result of the shear hardening of filling medium 30 and cannot move further. The further behaviour of the device corresponds to that of the devices from FIGS. 5 and 6.

[0087] FIG. 8 shows a simplified representation of a device 1 which differs from the device shown in FIG. 7 in that the surface of receptacle 20 runs conically in direction of movement B. As a result of the conical configuration of receptacle 20, in the case of the same dimension of first body 40 and of second body 60, gap dimension S1 of first body 40 is always larger than gap dimension S2 of second body 60. The behaviour of device 1 shown in FIG. 8 as a result of the introduction of a force F onto the first body corresponds to the behaviour of the devices from FIGS. 5, 6 and 7.

[0088] In order to return the devices represented in the above figures to an initial position, restoring means can be provided. These restoring means can be embodied, for example, elastically and connect the first body to the opposite side in the direction of movement of the receptacle. If the first body is deflected out of the initial position by an acting force, the elastic restoring means is expanded. If the external force and the holding force of the shear hardening abate, the elastic restoring means can convey the first body, the coupling element and the second body back into the initial position as a result of the previously experienced expansion.

[0089] The device can be used, for example, in the following products: shoes, trousers, jackets, shirts, stockings, gloves, protectors, protective clothing, prostheses, bandages, orthotics, tapes, helmets, shin guards, boots, dressings, etc.

[0090] Where applicable, all of the individual features which are represented in the individual exemplary embodiments can be combined with one another and/or exchanged without departing from the scope of the invention.

LIST OF REFERENCE SIGNS

[0091] 1 Device [0092] 20 Receptacle [0093] 22 Opening [0094] 24 Inner space [0095] 26 Inner surface [0096] 28 Step [0097] 30 Filling medium [0098] 40 First body [0099] 42 Shear surface [0100] 44 Force-transmission region [0101] 46 Spring seat [0102] 50 Force-transmission means [0103] 60 Second body [0104] 62 Shear surface [0105] 64 Outlet opening [0106] 66 Guide projection [0107] 68 Spring seat [0108] 70 Coupling element [0109] S1 Gap dimension [0110] S2 Gap dimension [0111] B Direction of movement [0112] F Force