PROTHESENFUSS

Description

[0001] The invention relates to a prosthetic foot with a foot element, a proximal connecting element arranged on the foot element, and a locking device that can be moved into a release position and a locking position, wherein the orientation in which the connecting element is arranged on the foot element can be changed when the locking device is in the release position.

[0002] Such prosthetic feet are known from the prior art. The proximal connecting element serves to attach the prosthetic foot to another prosthetic element, for example, a lower leg tube. The foot element is arranged on the connecting element. The orientation between the connecting element and the foot element can be changed when the locking device is in the release position. This allows, for example, adjustments to a changing heel height when the wearer of the prosthetic foot changes the shoe into which the prosthetic foot is inserted. InIn this case, the locking device is moved from the locked position to the released position. This is generally done by manually actuating a mechanical actuator. This actuator is, for example, a push button or a similar element, the actuation of which disengages two components of the locking device, thereby moving the locking device into the released position. The orientation between the foot element and the proximal connecting element can then be changed. Preferably, this means that the foot element is pivoted relative to the proximal connecting element about a pivot axis. This pivot axis preferably runs in a medial-lateral direction, i.e., transversely to the longitudinal extent of the foot, which extends from the heel to the toes.

[0003] Once the desired orientation is found, the locking device is moved from the release position to the locked position. InIn the locking position, the locking device prevents the orientation between the foot element and the proximal connection element from being changed. In In many designs, the actuating element that was already used to move the locking device from the locked position to the released position is actuated again. If the actuating element is actuated when the locking device is in the released position, the locking device is thereby moved into the locked position. This occurs, for example, by bringing the two components of the locking device back into engagement.

[0004] A disadvantage is that the actuating element must be pressed to move the locking mechanism from the release position to the locked position. Since the actuating element is usually located on the foot element or the proximal connecting element, the wearer of the prosthetic foot must move, for example, bend over, to operate this element. This is not particularly problematic for moving the locking mechanism from the locked position to the release position because the locking mechanism is already in the locked position at that time, and therefore the orientation between the foot element and the connecting element cannot be changed. However, when the locking mechanism needs to be moved from the release position to the locked position, it is already in the release position, so the orientation between the foot element and the proximal connecting element can be changed.The movement required to actuate the actuating element can easily cause such a change in orientation to occur accidentally, so that the desired orientation just found is again altered. EP 1 933 775 B1 describes a prosthetic foot with the features of the preamble of claim 1.

[0005] The invention is therefore based on the objective of improving a prosthetic foot in such a way that the orientation can be changed less easily when the changeability is to be stopped.

[0006] The invention solves the stated problem by means of a prosthetic foot according to the preamble of claim 1, which is characterized in that the locking device is designed in such a way that the locking device automatically moves from the release position to the locked position after a switching torque is applied to the foot element.

[0007] The switching torque, which can be, for example, a force impulse or a torque, causes the locking device to move from the release position to the locked position, without the use of any electronic component, such as a sensor or electrical control unit, for example, in the form of an electronic data processing device. The switching torque is not detected by a sensor, and the electronic sensor signal is not then used to switch the locking device, i.e., to move it from the release position to the locked position.

[0008] Since a switching torque must be applied to the foot element of a prosthetic foot according to the invention to move the locking device from the release position to the locked position, it is unnecessary to actuate an additional actuating element. While this is possible, it is not preferred. Preferably, the switching torque can be applied to the foot element when the wearer of the prosthetic foot is standing upright. This eliminates the need for the wearer to move their hand to reach an actuating element, which may be located on the foot element or the proximal connecting element. This also eliminates the risk of altering the established and approved orientation between the foot element and the proximal connecting element during such a movement.

[0009] The orientation of the foot element relative to the connecting element refers to the orientation in which the two elements are in relation to each other without the influence of external forces. This could be described as a neutral position or a rest orientation. In preferred embodiments, the foot element cannot be moved relative to the connecting element when the locking device is in the locked position. InIn alternative embodiments, however, it is possible to move the foot element relative to the connecting element, in particular to pivot it around the pivot axis, even when the locking device is in the locked position. This is not a change of orientation as defined by the present invention, but merely a change in the instantaneous position of the two elements relative to each other. This instantaneous position can be changed within a predetermined range, for example, a predefined angular range. For this to occur, an external force must act on the foot element or the connecting element, causing the movement of the two elements relative to each other. The orientation, i.e., the neutral or rest orientation that exists without the external forces, is not affected by this.

[0010] The switching torque moves the locking device from the release position to the locked position. However, this does not necessarily mean that the switching torque must be applied when the locking device is in the inactive position. InIn particular embodiments of the present invention, the switching torque is applied when the locking device is in the locked position. Preferably, the switching torque moves the device into the release position, and from there it automatically returns to the locked position, i.e., without the need for any further torque or actuation of an actuator. Preferably, these embodiments include a delay element that delays the moment at which the locking device moves from the release position to the locked position. Thus, in these embodiments, the locking position is moved into the release position by the switching torque. This allows the orientation between the foot element and the connecting element, for example, a lower leg, to be adjusted. The time period during which this adjustment is possible is determined by the delay element.Once the locking device returns to the locked position, the orientation can no longer be changed.

[0011] The switching torque is applied to the foot element. This does not necessarily have to be applied homogeneously or to all elements that make up the foot element. It is sufficient and in accordance with the invention if the switching torque is applied, for example, to only one component of the foot element. This component is preferably the actuating element, by the actuation of which the locking device moves from the locked position to the released position.

[0012] Preferably, the foot element is pivotable relative to the proximal connecting element about a pivot axis, wherein the switching torque is a torque about this pivot axis. Such a torque, the magnitude of which preferably must exceed a predetermined limit to act as a switching torque, can be applied, for example, by the wearer of the prosthetic foot changing the load on the prosthetic foot. The pivot axis can extend in a medial-lateral direction and be the axis about which the foot element is pivoted relative to the proximal connecting element to adjust the orientation between the two elements. In this case, to apply the switching torque, it is preferably sufficient for the wearer of the prosthetic foot to shift their weight forward toward the forefoot or backward toward the heel.

[0013] Preferably, the switching torque is a torque about a pivot axis extending from a heel area of ​​the prosthetic foot to a forefoot area. In this case, the switching torque can be generated by the wearer of the prosthetic foot applying weight to the right or left. This has the advantage that the switching torque cannot cause a change in the orientation between the foot element and the proximal connecting element. In this embodiment, the locking device is also designed to influence only the movement about the medially-laterally extending pivot axis around which the two elements are moved relative to each other to adjust their orientation.

[0014] Preferably, the prosthetic foot has an actuating element, for example, a push button. Actuating this actuating element preferably moves the locking device from the locked position to the released position. The switching torque preferably causes the actuating element to be actuated again, thus returning the locking device from the released position to the locked position. Preferably, the prosthetic foot has a delay element designed and configured to delay the effect of the switching torque. This gives the wearer of the prosthetic foot time to adjust the orientation between the foot element and the connecting element as desired before the locking device is moved from the released position to the locked position.

[0015] Preferably, the delay element comprises a component that is in a first position when the locking device is in the locked position and in a second position when the locking device is in the released position. This component can, for example, be the actuating element, preferably the mechanical actuating element, by actuating the locking device from the locked position to the released position. When the locking device is in the locked position, the actuating element is in the first position. From this first position, the actuating element is preferably moved to the second position, thereby moving the locking device to the released position. Alternatively or additionally, a component other than the actuating element is moved to the second position when the locking device is moved from the locked position to the released position.

[0016] The component is held in the second position by a holding mechanism. To return the component to the first position and thus return the locking device to the locked position, the holding mechanism is deactivated by the switching torque. The component is then preferentially subjected to a force that moves it from the second position to the first position. This force is applied, for example, by a spring.

[0017] Preferably, a fluid, for example a liquid or a gas, preferably air, is forced out of or drawn into a first volume when the component is moved from the second position to the first position. For this purpose, the fluid is preferably moved through a channel or conduit whose geometry creates flow resistance that opposes the fluid. The greater this flow resistance, the less fluid is moved through the channel or conduit for the same force. The amount of fluid flowing through the channel or conduit preferably limits the speed at which the force can move the component from the second position to the first position and thus the locking device from the release position to the locked position.

[0018] Preferably, the channel or pipe has a valve through which the flow resistance can be adjusted, preferably by limiting the free cross-section of the channel or pipe at least one point. Such a valve is, for example, designed as an orifice plate, which can preferably be moved into different positions and / or orientations relative to the channel or pipe, preferably rotated, thereby changing the cross-sectional area through which the flow resistance can be adjusted.

[0019] Preferably, the prosthetic foot has a hydraulic system with a first hydraulic chamber and a second hydraulic chamber connected by at least one hydraulic line, wherein hydraulic fluid is passed from one hydraulic chamber to the other to change the orientation, the hydraulic system having a valve arrangement by which the hydraulic line is closed when the locking device is in the locked position. Preferably, the hydraulic line is open when the locking device is in the unlocked position.

[0020] In In a preferred embodiment, the valve arrangement has an actuating element that can be moved into a flow position and a closed position and is designed and configured such that it is moved from the flow position to the closed position by the switching torque.

[0021] Advantageously, the actuating element moves from the flow position to the closed position against a damping force, preferably generated by at least one friction element and / or a viscous element. The actuating element is, for example, a valve body or another component of the valve assembly, which is moved from the flow position to the closed position by being displaced along a predetermined path. InIn a preferred embodiment, this movement is slowed, or damped, by at least one friction element, for example, one or more sealing rings. The stronger the damping, the slower the movement of the actuating element and the longer it takes for the valve assembly to close the hydraulic line and thus bring the locking device into the locked position. The time available to the prosthetic foot wearer between the application of the switching torque and the point at which the locking device is in the locked position can be adjusted in this way. Alternatively or additionally, the movement of the actuating element from the flow position to the closed position can also take place within a viscous medium. The more viscous the medium, the more viscous it is and the longer it takes the actuating element to move from the flow position to the closed position.

[0022] InIn a preferred embodiment, the valve arrangement has a hydraulic volume in which the actuating element is located and which is connected to the first hydraulic chamber by means of a first hydraulic connection and to the second hydraulic chamber by means of a second hydraulic connection, wherein the first hydraulic connection can be closed by a first valve and the second hydraulic connection by means of a second valve. Preferably, the first valve and the second valve are open by the actuating element when the actuating element is in the flow position. In this case, the actuating element is not the valve body or any other component that closes the respective connection, but merely ensures that these components or valve bodies are moved from the closed position to the flow position when the actuating element is actuated.

[0023] Preferably, the first and second valves are closed simultaneously after the actuating element has been moved into the closed position by the switching torque. This is particularly advantageous when no movement is possible between the base element and the proximal connection element while the locking device is in the locked position.

[0024] In In an alternative embodiment, the first and second valves are closed sequentially after the actuating element has been moved to the closed position. This is particularly advantageous if movement between the base element and the connection element is possible even when the locking device is in the locked position. However, even in this embodiment, the orientation between the base element and the connection element can only be changed when the locking device is in the released position.

[0025] The invention further solves the stated problem by means of a prosthetic foot with a foot element, a proximal connecting element arranged on the foot element, and a locking device which can be moved into a release position and a locked position, wherein the orientation in which the connecting element is arranged on the foot element is changeable when the locking device is in the release position, wherein the locking device has a first positive locking element and a second positive locking element which are engaged with each other when the locking device is in the locked position and which are disengaged when the locking device is in the release position.

[0026] Preferably, the first positive locking element is part of the foot element and the second positive locking element is part of the proximal connection element. InIn a preferred embodiment, the two positive locking elements are disengaged by pivoting the foot element relative to the connecting element about a switching axis, which is preferably a vertical axis or at least runs from proximal to distal. Particularly preferably, the locking device has a locking element that must be removed from its locking position to disengage the two positive locking elements.

[0027] To adjust a heel height in this embodiment, the locking element is first removed from its locking position. InIn a second step, the two interlocking elements are disengaged. This can be achieved, for example, by moving the two components on which the respective interlocking elements are located relative to each other. This could involve, for instance, pivoting the foot element and the proximal connecting element relative to each other about a pivot axis. The movement can be quite small, provided it is sufficient to disengage the interlocking elements. The desired plantar flexion angle can then be set, for example, by applying a torque around the axis to be adjusted. This allows the foot element to be tilted or rotated relative to the proximal connecting element, thus setting the desired angle. Finally, the disengagement movement is reversed, re-engaging the two interlocking elements.After that, a change in the plantar flexion angle is not possible without disengaging the two positive locking elements. Finally, the locking element is returned to its locking position to prevent accidental disengagement.

[0028] With the aid of the accompanying figures, some embodiments of the invention are explained in more detail below. They show: Figures 1 and 2 – schematic representations of a part of a prosthetic foot according to a first embodiment of the present invention; Figures 3 to 5 – schematic representations of a part of a prosthetic foot according to another embodiment of the present invention; Figure 6 – the schematic sketch of the function of a further embodiment; Figures 7 to 10 – schematic representations of another embodiment of a prosthetic foot; Figure 11 – the schematic sectional view through a section of a prosthetic foot; and Figure 12 – the schematic representation of a part made of Figure 11 in a different view.

[0029] Figure 1Figure 4 shows part of a hydraulic system and a locking device for the prosthetic foot. This device has an actuating element 2 in the form of a push button. The hydraulic system has a first hydraulic chamber and a second hydraulic chamber, which are connected to each other, so that when the orientation of the foot element changes relative to the proximal connection element, hydraulic fluid is directed from one hydraulic chamber to the other. The first hydraulic chamber 4 is located in Figure 1 to be recognized section by section.

[0030] The actuating element 2, like the locking device, is in the locked position. The first hydraulic chamber 4 is connected via a first hydraulic connection 6, in which a first check valve 8 is located, to a hydraulic volume 10 into which the actuating element 2 projects. InIn the illustration shown, the first check valve 8 is closed, so no fluid can flow from the first hydraulic chamber 4 into the hydraulic volume 10. The second hydraulic chamber (not shown) is connected to the hydraulic volume 10 via a second hydraulic connection 12, in which a second hydraulic valve 14 is located.

[0031] Figure 2 shows the design from Figure 1 , wherein the actuating element 2 was actuated by being pushed upwards as shown. The actuating element 2 has a piston 16 that projects into the hydraulic volume 10 and which has projections 18. When the actuating element 2 is actuated as shown Figure 2When actuated as shown, the piston 16 also moves, and with it the projections 18. The projections 18 open the first check valve 8 and the second check valve 14 by moving the switching levers 20. These push the balls of the check valves 8 and 14 upwards in the illustration, thus opening the first fluid connection 6 and the second fluid connection 12. This allows fluid to flow from the two hydraulic chambers into the fluid volume 10.

[0032] The piston 16 has a plunger 22 at its end facing away from the actuating element 2, which is also displaced when the actuating element 2 is actuated. A switching line 24 exists between the hydraulic volume 10 and the first hydraulic chamber 4, but this line does not allow fluid to be exchanged between the first hydraulic chamber 4 and the hydraulic volume 10. The first hydraulic chamber 4 is separated from the hydraulic volume 10 by a diaphragm 25, which has two stable states. It can also be referred to as a bistable diaphragm 25. The diaphragm 25 is, for example, made of a metal. In the embodiment shown, the diaphragm 25 is in a first stable state, which is Figure 1 As shown, it is curved downwards. When the actuating element 2 is now actuated and the piston 16 is moved with the plunger 22, the plunger 22 presses against the diaphragm 25 and thus moves it out of the in Figure 1 shown first stable state in the in Figure 2 shown second stable state.

[0033] In the Figure 2 In the illustrated state of the actuating element 2, the actuating element 2 is in its flow position, allowing fluid to be exchanged between the two hydraulic chambers. To return the locking device, to which the actuating element 2 belongs in this configuration, to the locked position, a switching torque must be applied to the foot element (not shown). In the illustrated embodiment, this is achieved by applying pressure to the forefoot of the prosthetic foot. This leads to an increase in pressure in the first hydraulic chamber 4 and thus also in the switching line 24 connected to it. This causes the diaphragm 25 to return to the position shown. Figure 1 The first stable state shown was pressed and the actuating element 2 was moved from its flow position, which is in Figure 2As shown, the piston 16 is moved into its closed position. This causes the piston 16 with the projections 18 to move downwards, which also moves the switching levers 20 back and closes the check valves 8, 14. The locking device is then back in the closed position.

[0034] The Figures 3 to 5 show a slightly different design, which is the one in the Figures 1 and 2 The design shown, however, is very similar. Here too, the hydraulic volume 10 is located between the two hydraulic chambers, of which again only the first hydraulic chamber 4 is shown. This is connected to the hydraulic volume 10 via the first hydraulic connection 6, in which the first check valve 8 is located. The second hydraulic chamber, which is located in the Figures 3 to 5 The hydraulic volume 10, which is also not shown, is connected via the second hydraulic connection 12. In The second hydraulic connection 12 contains the second check valve 14. In Figure 3 The actuating element 2 has been actuated and the piston 16 with the projections 18 has been displaced. Unlike in the embodiment of the Figures 1 and 2 are the two leads 18 in the Figures 3 to 5 not trained identically. In the in Figure 3 However, in the situation shown, both check valves 8, 14 are open.

[0035] Another difference between the design of the Figures 3 to 5 and the design of the Figures 1 and 2 is located in switching line 24, which is in the Figures 3 to 5A switching volume 26 with a floating piston 28 is located. The floating piston 28 divides the switching volume 26 into two sections, which can also be referred to as chambers. The first section is located above the floating piston 28 and is connected to the first hydraulic chamber 4 via the switching line 24. The second section is located below the floating piston 28 and is connected to the hydraulic volume 10 via another check valve 30.

[0036] In Figure 3The piston 16 with the projections 18 is shifted upwards to such an extent that both shift levers 20 open the respective check valves 8, 14, thus enabling a connection between the two hydraulic chambers and the hydraulic volume 10. If the switching torque is applied in this situation, which can consist, for example, of a load on the forefoot, the pressure within the first hydraulic chamber 4, and thus also in the switching line 24, is increased. The floating piston 28 is moved downwards until it closes the switching valve 30, thereby moving the actuating element 2 from its flow position to the closed position. This situation is described in Figure 4 depicted.

[0037] The in Figure 4 The left projection 18 of the piston 16 is designed such that the corresponding shift lever 20 can be disengaged from the Figure 4The piston 16, which is moving downwards, can move again in the position shown, and thus closes the first check valve 8 due to the prevailing pressures. This situation is described in Figure 5 The first check valve 8 is already closed, while the second check valve 14 is still open due to the larger projection 18. Therefore, it is still possible for fluid from the second hydraulic chamber (not shown) to enter the hydraulic volume 10 through the open second check valve 14 and from there into the second part of the switching volume 26, thereby moving the floating piston 28 back upwards.

[0038] This means that even after the first check valve 8 is closed, movement of the foot element relative to the connection element is possible by moving the floating piston 28. This allows for positioning of the two elements relative to each other that is independent of the step height.

[0039] Figure 6 This schematically shows another design of a locking device. The actuating element 2, which is located in... Figure 6 in its flow position. Figure 6 The actuator 2 is moved from its closed position from right to left. It reaches the flow position when the hook 32 engages in the designated recess 34 and thus holds the actuator 2 in its flow position. Applying a switching torque moves a pin 36 upwards, ensuring that the hook 32 no longer engages in the recess 34, thereby compressing the retaining spring 38. As soon as the hook 32 no longer holds the actuator 2, the push spring 40 returns it to the closed position.

[0040] The Figures 7 to 10 show a different design of a prosthetic foot. Figure 8Figure 1 schematically shows a proximal connection element 42, on which a first positive locking element 44 is arranged and which is connected to a base element 46. A second positive locking element 48 is arranged on the base element 46, which is located in the Figure 8 The situation shown involves the first positive locking element 44 in engagement. Figure 7 Figure 1 shows a top view in which part of the connecting element 42 and the second positive locking element 48 can be seen. Additionally, a locking element 50 is shown, which prevents the first positive locking element 44 and the second positive locking element 48 from being disengaged.

[0041] In Figure 9 The locking element 50 has been removed and the foot element 46 has been rotated relative to the connecting element 42 about a switching axis that extends perpendicular to the plane of the drawing. It can be seen that the second positive locking element 48 is different from the one shown in the diagram. Figure 7The foot element 46 is no longer positioned at the upper end of the recess in the connecting element 42, but at the lower end of this recess. This illustrates that the foot element 46, and thus also the second positive locking element 48, has been rotated relative to the connecting element 42. As a result, the first positive locking element 44 and the second positive locking element 48 have been disengaged, and the foot element 46 can be reoriented relative to the connecting element 42. To do this, it is, as shown in Figure 10 depicted rotated around a pivot axis running from medial to lateral.

[0042] Figure 11Figure 50 shows a section of a schematic sectional view through part of a locking device. Component 50, which in the illustrated embodiment is the actuating element used to move the locking device from the locked position to the released position, is in the second position. The locking device is therefore in the released position. Component 50 was moved into the position shown by the switching torque. The spring 52 exerts a force on component 50, which, in the illustrated example, moves component 50 to the right into the first position. As soon as component 50 reaches this first position, the locking device is in the locked position.

[0043] The spring 52 is located in a first volume 54, which increases in size when the spring 52 relaxes and the component 50 moves to the right. Therefore, a fluid, for example, air, is drawn into the volume 54 through a line (not shown). The fluid is forced out of the volume 54 through the line 56 when the component 50 moves to the left due to the switching torque, thus reducing the volume 54. The flow resistance opposing the backflow of the fluid into the volume 54 is limited by an orifice 58, which acts as a throttle valve. This limits the speed at which the spring 52 moves the component 50, causing it to reach its final position with a delay.

[0044] Figure 12 Figure 58 shows a top view of the aperture. It has an elongated hole 60 that connects to an opening 62 of the return line, which is located in Figure 11not shown, and through which the fluid flows back into volume 54, depending on the position of the aperture 58, it is more or less closed off, thus creating more or less flow resistance. Reference symbol list

[0045] 2 Actuating element 4 First hydraulic chamber 6 First hydraulic connection 8 First check valve 10 Hydraulic volume 12 Second hydraulic connection 14 Second check valve 16 Piston 18 Projection 20 Shift lever 22 Plunger 24 Switching line 25 Diaphragm 26 Switching volume 28 Floating piston 30 Check valve 32 Hook 34 Recess 36 Pin 38 Retaining spring 40 Thrust spring 42 Connection element 44 First positive locking element 46 Foot element 48 Second positive locking element 50 Component 52 Spring 54 Volume 56 Line 58 Orifice

Claims

1. A prosthetic foot with a foot element, a proximal connection element (42) arranged on the foot element and a blocking device that can be brought into a release position and a blocking position, wherein an orientation in which the connection element (42) is arranged on the foot element can be modified when the blocking device is in the release position, characterized in that the blocking device is designed in such a way that the blocking device automatically moves from the release position into the blocking position once a switching torque is applied to the foot element.

2. The prosthetic foot according to claim 1, characterized in that the blocking device can be brought out of the blocking position into the release position by actuating a mechanical actuation element (2), wherein the actuation element is preferably actuated by applying the switching torque.

3. The prosthetic foot according to claim 1 or 2, characterized in that the prosthetic foot, preferably the blocking device, comprises a delay element that is designed and configured to delay the effect of the switching torque of moving the blocking device out of the release position into the blocking position.

4. The prosthetic foot according to one of the preceding claims, characterized in that the foot element can be swivelled relative to the connection element about a swivel axis and the switching torque is a torque about the swivel axis.

5. The prosthetic foot according to claim 4, characterized in that the swivel axis extends from a heel area of the prosthetic foot to a forefoot area of the prosthetic foot.

6. The prosthetic foot according to one of the preceding claims, characterized in that the prosthetic foot comprises a hydraulic system with a first hydraulic chamber (4) and a second hydraulic chamber that are connected by at least one hydraulic line, wherein hydraulic fluid is directed from one hydraulic chamber into the other hydraulic chamber in order to modify the orientation, wherein the hydraulic system comprises a valve arrangement by means of which the hydraulic line is closed when the blocking device is in the blocking position.

7. The prosthetic foot according to claim 6, characterized in that the valve arrangement comprises an actuation element which can be brought into a through-flow position and a closing position, and which is configured and designed in such a way that it is brought out of the through-flow position into the closing position by the switching torque.

8. The prosthetic foot according to claim 7, characterized in that the actuation element (2) moves out of the through-flow position into the closing position against a damping force, which is preferably generated by at least one friction element and / or one viscous element.

9. The prosthetic foot according to claim 7 or 8, characterized in that the valve arrangement comprises a hydraulic volume (10) in which the actuation element (2) is located and which is connected to the first hydraulic chamber by means of a first hydraulic connection (6) and to the second hydraulic chamber by means of a second hydraulic connection (12), wherein the first hydraulic connection can be closed by a first valve and the second hydraulic connection (12) by a second valve.

10. The prosthetic foot according to claim 9, characterized in that the first valve and the second valve are opened by the actuation element (2) when the actuation element is in the through-flow position.

11. The prosthetic foot according to claim 10, characterized in that the first valve and the second valve are closed at the same time once the actuation element (2) has been brought into the closing position.

12. The prosthetic foot according to claim 10, characterized in that the first valve and the second valve are closed one after the other once the actuation element (2) has been brought into the closing position.