Hydraulic actuator and regulating valve

Abstract

The invention relates to a hydraulic actuator for an orthopedic device, comprising a control valve in a flow channel which has an inlet and an outlet for a hydraulic fluid. The control valve has a valve sleeve and a valve body. The valve sleeve has a sleeve wall which forms a receiving space and in which at least one radially oriented inlet opening is formed. The valve body is movably arranged in the receiving space of the valve sleeve between a closed position and an open position and opens into the outlet. The valve body has at least one valve body wall, which is opposite the at least one inlet opening and in which a channel opening is formed, which in the open position is opposite the corresponding inlet opening. The valve body forms a cavity in which a diffuser insert is arranged, which diverts the hydraulic fluid in the direction of the outlet.

Description

Technical Field

[0001] The invention relates to a hydraulic actuator for an orthopedic device, comprising a regulating valve in a flow channel, the flow channel having an inlet and an outlet for a hydraulic fluid. The regulating valve comprises a valve sleeve and a valve body, the valve sleeve having a sleeve wall, the sleeve wall forming a receiving space and forming at least one radially oriented inlet opening in the sleeve wall, the valve body being arranged in the receiving space of the valve sleeve so as to be movable between a closed position and an open position, opening into the outlet and having at least one valve body wall, the valve body wall being opposite the at least one inlet opening and forming a through-flow opening in the valve body wall, the through-flow opening being opposite the corresponding inlet opening in the open position. Background Art

[0002] Orthopedic devices include, in particular, but are not limited to, prostheses, orthoses and exoskeletons. Prostheses replace missing or no longer existing limbs. Orthoses and exoskeletons are fixed to a limb and support, influence or limit certain movements or postures of the limb. In the case of cross-joint orthoses or exoskeletons, the upper part is fixed to the proximal end of the limb and the lower part is fixed to the distal end of the limb and are pivotably connected to each other via a joint.

[0003] The prosthesis may have a proximal upper part and a distal lower part, between which a joint device is arranged to achieve a pivotable connection between the upper part and the lower part.

[0004] Between the proximal upper part and the distal lower part of the orthopedic device, an actuator or a resistance device can be arranged, which can influence the deflection movement between the upper part and the lower part. This influence can be achieved by providing a resistance, for example by a hydraulic damper or a pneumatic damper. In order to actively support the movement, the orthopedic device is equipped with a drive device or a power storage device to actively realize the movement or to convert and store kinetic energy. Instead of a joint device, the orthopedic device can also influence a linear displacement between the two components.

[0005] In order to be able to influence the movement between two components (for example the upper and lower parts of a joint device), a device for influencing the flow resistance is arranged in the flow channel of the hydraulic actuator, which can be designed as a hydraulic drive or a passive damper. Usually, one or more regulating valves are arranged in the flow channel separated by a piston between two hydraulic chambers, by which the flow cross section can be adjusted. The adjustment can be carried out based on sensors, especially during the use of the orthopedic device. For this purpose, the sensor data is detected and transmitted to the control unit. The sensor data is analyzed in the control unit and converted into control signals during the use of the orthopedic device, on the basis of which the regulating valve is adjusted. In this way, the orthopedic device can be adapted to the corresponding usage situation.

[0006] Due to the relatively small dimensions and high pressures in the orthopedic device, the flow velocities in the flow channels and therefore also in the control valves are high. This sometimes results in high noise levels, which are perceptible not only to the user of the orthopedic device but also to the surroundings. In addition, the hydraulic actuator in the area of ​​the control valve is susceptible to flow losses, which leads to an increase in the basic resistance in the orthopedic device. As a result, the control accuracy decreases and the deflection properties of the joint components or the movement properties of the components in which the hydraulic actuator is located are affected over the long term. Summary of the invention

[0007] The object of the present invention is to provide a hydraulic actuator and a regulating valve for an orthopedic device, by means of which greater comfort of use and improved control properties can be provided.

[0008] The object can be achieved by a hydraulic actuator having the features of a preferred technical solution and a control valve having the features of a preferred technical solution. Advantageous solutions and developments of the present invention are disclosed in the optional technical solution, the description and the drawings.

[0009] A hydraulic actuator for an orthopedic device has a regulating valve in a flow channel, the flow channel having an inlet and an outlet for a hydraulic fluid, wherein the regulating valve has a valve sleeve and a valve body, the valve sleeve having a sleeve wall, the sleeve wall forming a receiving space and forming at least one radially oriented inlet opening in the receiving space, wherein the valve body is arranged in the receiving space of the valve sleeve so as to be movable between a closed position and an open position and opens into the outlet, wherein the valve body has at least one valve body wall, which is opposite to the at least one inlet opening and in which a flow opening is formed, which in the open position is opposite to the corresponding inlet opening, characterized in that the valve body forms a cavity, in which a diffuser insert is arranged, which diverts the hydraulic fluid in the direction of the outlet. The diffuser insert prevents the hydraulic fluid flowing radially from hitting the opposite wall of the valve body or mixing or hitting the hydraulic flow flowing in from another inlet opening. Otherwise, this would lead to turbulence in the cavity in the valve body, resulting in high noise and increased flow resistance, especially when the flow opening is fully open. The diffuser insert in the valve body cavity deflects the hydraulic fluid so that it does not hit the valve body wall at a right angle, but instead deflects it in the direction of the outlet. This prevents the formation of dead space and turbulence in the valve body cavity, thereby reducing flow resistance and noise.

[0010] In one embodiment, the cavity is designed to be closed, except for at least one passage opening and an outlet opening, because in particular the cavity end wall opposite the outlet opening is closed. A plurality of throughflow openings corresponding to the inlet openings in the sleeve wall can be formed in the valve body wall so that a plurality of partial flows of the hydraulic fluid can be introduced into the cavity. The otherwise closed design of the cavity can promote effective deflection of the hydraulic fluid.

[0011] In one embodiment, the diffuser insert is manufactured separately from the valve body and is fastened to or in the valve body. As a result, the diffuser insert can be manufactured from a different material than the valve body, in particular from a different material than the valve body wall, on which one or more inlet openings are formed. In addition, the separate manufacture of the diffuser insert also makes it possible to adapt the outer contour or geometry of the diffuser insert to different conditions of use or models and to different hydraulic actuators. In addition, complex three-dimensional structures with free access from the outside can be manufactured more easily than with a sleeve-type valve body. Alternatively, the valve body is an integral component of the valve body and is manufactured, for example, within the framework of an additive manufacturing process, in which complex three-dimensional structures can be manufactured by stacking layers of material in layers during forming.

[0012] In one embodiment, the valve body has a plurality of channel openings and the diffuser insert has partition walls arranged between the channel openings. As a result, the flow channels of the respective channel openings can be separated and redirected separately. Different flow conditions can exist in the flow channels, so that the partial flows can also be redirected in different ways in order to achieve an optimal influencing and redirection of the partial flows.

[0013] In one embodiment, the partition wall does not extend to the outlet, but only divides the cavity of the valve body over a partial axial extension, so that the individual partial flows of the hydraulic fluid merge in the cavity. It is advantageous if the partition wall tapers toward the outlet, so that the cross section of the fluid flow gradually widens, in order to minimize turbulence, in particular to maintain or generate a laminar flow. In an alternative, the partition wall extends all the way to the outlet, so that the individual partial flows merge only after the outlet.

[0014] In one embodiment, the valve body is rotatably or movably supported in the valve sleeve. By rotating or moving the valve body in the valve sleeve, different cross sections can be provided for the hydraulic fluid in the valve body cavity. The total available inlet cross section originates from the overlapping geometry of the inlet opening and the passage openings respectively opposite. In a static valve sleeve and a valve body movably supported relative to it, the inlet cross section can be increased or reduced due to relative movement, and in extreme cases, the inlet cross section is completely closed. Through the corresponding geometry of the inlet opening and the passage opening, the optimal cross section for the inlet opening can be generated for each torsion angle or each displacement position. For example, starting from the closed position, initially only the inlet cross section is slowly increased and only gradually increased from a predetermined torsion angle or displacement position, and then the increase is reduced until the fully open position, so as to make fine adjustments, which may be meaningful and desirable. Conversely, it is also possible to choose a smaller change in the unit displacement stroke or unit adjustment angle in the medium opening range, so as to make fine adjustments in the medium damping range or activation range.

[0015] In one embodiment, the valve body is coupled to an adjusting device, by means of which the valve body can be adjusted or moved to a desired position and held in a desired position. The adjusting device can be coupled to a manual or electric drive; the adjusting device can also be coupled to a mechanical drive, for example to achieve path- or load-dependent opening or closing of the inlet cross section.

[0016] In one embodiment, the diffuser insert is configured to taper in the direction of the outlet so as to increase the flow cross section gradually in the direction of the outlet.

[0017] The valve sleeve can be designed as part of a hydraulic actuator housing, for example a damper housing. Alternatively, the valve sleeve can be designed as a separate component, so that the regulating valve consisting of valve sleeve, valve body and diffuser insert can be designed as a modular unit and can be manufactured separately. Such a regulating valve can be inserted into the hydraulic actuator and, if necessary, can also be coupled to the regulating device.

[0018] The inlet and the outlet can be fluidically connected to the piston-cylinder unit of the orthopedic device and to two chambers separated by the piston of the piston-cylinder unit. A hydraulic circuit is thus established between the inlet and the outlet. In principle, there can be only one flow channel between the chambers of the piston-cylinder unit in which the regulating valve is located. In this case, the diffuser insert is only effective in one direction, in the opposite direction, the inlet will be the outlet and the hydraulic fluid will flow back to the inlet opening under high pressure through the cavity and the channel opening. It is preferred to arrange a plurality of regulating valves in the hydraulic connection between the chambers, in particular to be able to influence the regulating movement separately.

[0019] In one embodiment, the inlet opening and / or the outlet opening are oriented obliquely relative to the longitudinal extension of the regulating valve and are designed as a slot. The slot can be straight, i.e. have a constant slope on the circumference of the valve sleeve and / or the valve body. Alternatively, the slot is curved or at least regionally curved, whereby different overlaps of the inlet opening and the outlet opening can be achieved with a uniform regulating movement. The width of the slot can be varied along its longitudinal extension to achieve an increase or decrease in the width along its longitudinal extension direction or along the axial extension direction of the regulating valve. In this way, a suitable change of the inlet cross section into the cavity can be achieved.

[0020] The invention also relates to a regulating valve as described above, which is designed as a modular unit and consists of a valve sleeve and a valve body and a corresponding diffuser insert. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. In the accompanying drawings:

[0022] Figure 1 a schematic diagram showing a prosthesis being worn;

[0023] Figure 2 A schematic diagram showing a prosthetic leg;

[0024] Figure 3 A cross-sectional view of a regulating valve is shown;

[0025] Figure 4 A single schematic diagram showing a diffuser insert;

[0026] Figure 5 A cross-sectional view showing a regulating valve assembly;

[0027] Figure 6 showing a perspective view of a diffuser insert;

[0028] Figure 7 A view of the diffuser insert is shown from an oblique rear view;

[0029] Figure 8 showing a cross-sectional view of a valve body with a diffuser insert;

[0030] Fig. 9 An exploded view of a regulating valve is shown;

[0031] Fig.10 Show Fig. 9 The regulating valve is shown in the open position;

[0032] Fig.11 Show Fig.10 A perspective view of the regulating valve is shown;

[0033] Fig.12 A longitudinal section view of a regulating valve is shown;

[0034] Fig.13 A cross-sectional view showing an open regulating valve;

[0035] Fig.14 a perspective view showing a closed regulating valve;

[0036] Fig.15 Show Fig.14 A cross-sectional view of the regulating valve shown;

[0037] Fig.16 A perspective view showing a regulating valve;

[0038] Fig.17 Show Fig.16 A partial transparent view of the regulating valve is shown;

[0039] Fig.18 Show Fig.17 A partially closed view of the regulating valve shown;

[0040] Fig.19 Show Fig.18A flow diagram in a regulating valve as shown; and

[0041] Fig. 20 Show Fig.16 A cross-sectional view of the regulating valve is shown. DETAILED DESCRIPTION

[0042] Figure 1 A person is shown wearing a lower limb orthosis device having an upper part 100 with a prosthesis shaft and a lower part 200 in the form of a lower leg part having a prosthetic foot fastened thereto at the distal end. The upper part 100 can be pivoted relative to the lower part 200 about a pivot 150 .

[0043] Figure 2A schematic diagram of an orthopedic joint device in the form of a lower limb prosthesis is shown. The orthopedic joint device has an upper part 100 and a lower part 200, which are pivotally supported on each other about a pivot 150. In order to influence the relative deflection of the upper part 100 relative to the lower part 200 about the pivot 150, an actuator 300 is arranged on the upper part 100 and the lower part 200, which is designed as a hydraulic damper in the embodiment shown. The hydraulic damper 300 is designed as a piston-cylinder unit and has a cylinder in a housing, which is divided into two hydraulic chambers 310, 320 by a piston 330, and the piston is coupled to a piston rod. There is at least one fluid connection between the two hydraulic chambers 310 and 320, so that when a hydraulic chamber is enlarged, hydraulic fluid can flow into the hydraulic chamber, and vice versa, when the hydraulic chamber is reduced, the hydraulic fluid can flow out of the hydraulic chamber and into the opposite hydraulic chamber. A regulating valve is arranged in the fluid technology connection between the two chambers 310 and 320, which is not shown, and the regulating valve will be described in detail below. In an alternative embodiment, the actuator 300 can be an active actuator with a drive device, such as an electric motor, a power storage device or other types of drive devices, to influence the deflection movement of the upper part 100 relative to the lower part 200. In the illustrated embodiment, the actuator 300 is designed as a passive actuator to provide resistance for flexion movement and, if necessary, also for extension movement. The actuator 300 is coupled to a control device 400, which is arranged on the lower part 200 in the illustrated embodiment. The control device 400 is coupled to a sensor 500, which is arranged on the upper part 100 and / or the lower part 200. The sensor 500 can detect state variables of the joint device, such as position, orientation, force, torque, acceleration or the posture of the components in space or relative to each other, wherein a plurality of sensors can be used to detect the desired state variables of the orthopedic joint device. The sensor 500 is coupled to the control device 400 and transmits corresponding sensor data or sensor signals to the control device 400, wherein the ability of the actuator 300 to influence the deflection movement or deflectability of the upper part 100 relative to the lower part 200 is changed according to the sensor value or sensor data. For example, the flexion resistance and / or extension resistance is changed according to the sensor value. For this purpose, a valve or a throttle device can be adjusted. In an alternative embodiment, the magnetic field can be changed to change the viscosity of the magnetorheological fluid. In a mechanical brake device, the braking force can be increased or reduced so that the actuator 300 produces a suitable resistance performance. In an active drive device with at least one electromechanical actuator, resistance to movement can be applied by current and voltage, but movement can also be supported. In addition to applying torques and torque curves, trajectories can also be tracked by control algorithms and sensor information about the deflection movement of the upper part 100 and the lower part 200, or system performance can be simulated in the sense of impedance or admittance control.For example, the properties of linear or nonlinear springs, the properties of dampers or inertia, or a combination of properties, can be simulated so that a deflection movement that resists buckling can be influenced. This type of control offers a high degree of flexibility. Deflection movements can also be actively supported by this control. If a torque or force is applied by the actuator without a deflection occurring, for example because external and internal forces are in equilibrium, the deflection movement is also subject to resistance. The actuator can also activate and deactivate energy storage devices, such as hydraulic spring accumulators, change the transmission ratio of the drive devices and / or couple or decouple them. These types of drives can also be used to influence deflection movements. The resistance is the force and torque applied by the actuator to influence the deflection movement. The resistance can act in opposition to the deflection movement, but it can also support the deflection movement, i.e. act in the direction of the deflection.

[0044] The biosignal sensor 600 is constructed on the upper part 100 or fastened on the upper part, such as a prosthesis sleeve or a bracket, and is configured to detect muscle activity or drive muscles or muscle tissues and generate biosignals, which are transmitted to the control device 400. The biosignal sensor 600 can be designed as a discharge electrode, which is coupled to the control device 400 through a conductive connection or wirelessly and transmits a corresponding signal to the control device 400, and the control device also activates, deactivates or modulates the actuator 300 according to the biosignal to change the resistance or affect the movement behavior or the mobility between the components.

[0045] Instead of designing the orthopedic joint device as a prosthesis, it can also be designed as an orthosis, wherein a calf splint is formed on the artificial knee joint to replace the calf part as the lower part 200. The upper part 100 is a thigh splint, which can be fixed to the thigh by a corresponding fastening device (such as a belt, shell or cuff). The biosignal sensor 600 can be fastened to the thigh or other muscle groups separately, or it can be arranged on the fastening device. The orthopedic joint device can also be designed as an exoskeleton as a special form of orthosis. As an alternative to the illustrated embodiment of the lower limb orthopedic joint device, the orthopedic joint device can also be designed for the upper limbs, for example as an artificial shoulder joint or artificial elbow joint of a prosthetic arm, or as an orthosis or exoskeleton of an arm.

[0046] The activation, deactivation and, if necessary, modulation of the actuator for influencing the deflection movement or deflectability of the joint device are carried out according to at least one signal from a sensor, i.e., if there is a corresponding sensor signal, the influence on the deflection movement or the anti-flexion deflectability will increase. Influencing the deflection movement can also be understood as preventing the deflection movement, thereby locking the lower part 200 relative to the upper part 100, and then no relative movement occurs or cannot occur between the two parts. Therefore, the deflectability of the upper part 100 relative to the lower part 200 can be affected by locking the joint in the flexion direction or increasing the flexion resistance. This influence can be achieved by a passive or active actuator. In order to reduce the increased flexion resistance of the joint device again, it can be controlled according to the sensor value, i.e., the value transmitted to the control device 400 by this sensor 500 or these sensors 500 and / or the biosignal sensor 600. This control of an orthopedic joint device (e.g., a lower limb) is advantageous and useful, for example, for the standing function, in which flexion (e.g., flexion of the knee joint) becomes difficult or locked. For example, the influencing of the deflection movement can be influenced by adjusting a control valve.

[0047] Figure 3 A cross-sectional view of a regulating valve 10 is shown, which is arranged in a flow channel 1 between one of two chambers 310, 320 (not shown in the figure). In the flow channel, the hydraulic fluid is supplied to the inlet 2 of the regulating valve 10. As soon as the hydraulic fluid flows through the regulating valve 10, it leaves through the outlet 3. The regulating valve 10 has a valve sleeve 20, which is designed to be essentially cylindrical in the illustrated embodiment. The valve sleeve 20 has a sleeve wall 22, which surrounds a receiving chamber 23. The valve body 30 is arranged in the receiving chamber 23. The hydraulic fluid flows out of the flow channel 1 from the inlet 2 through the inlet opening 24 in the direction of the valve body 30. At Figure 3 Only one inlet opening 24 is shown in the cross-sectional view of FIG. 2 , which is divided into two partial inlet openings. The inlet opening 24 is oriented radially so that a hydraulic fluid supplied to the inlet opening 24 from the outside through the flow channel 1 circumferentially surrounding the valve sleeve 20 can enter the interior of the valve sleeve 20. The flow channel 1 is arranged annularly around the valve sleeve 20 so that the hydraulic fluid can flow to the valve body 30 through a plurality of inlet openings.

[0048] The valve body 30 is movable in the receiving chamber 23 of the valve sleeve 20 and is supported in a rotatable manner in the illustrated embodiment. The regulating valve 10 can be opened or closed by twisting the valve body 30 in the valve sleeve 20. For this purpose, the valve body 30 is twisted between a closed position and an open position. In the intermediate position, the regulating valve 10 is partially open or partially closed, resulting in a reduced flow of the hydraulic fluid. At the same time, the flow resistance in the hydraulic system increases, so that the resistance of the hydraulic actuator can be adjusted. In order to allow the hydraulic fluid to flow from the inlet 2 to the outlet 3 through the inlet opening 24, the valve body 30 has at least one valve body wall 32, which is opposite to this inlet opening 24 or these inlet openings and forms at least one channel opening 34 therein, which in the open position is opposite to the corresponding or opposite inlet opening 24. In the open position, the maximum cross section of the hydraulic fluid channel opening is formed due to the overlap of the inlet opening 24 and the channel opening 34. In the closed position, the cross section of the channel opening is 0, so that the hydraulic fluid cannot flow from the inlet 2 to the outlet 3. By twisting the valve body 30 in the receiving chamber 23 , different channel cross sections can be produced in order to set a desired hydraulic resistance.

[0049] for Figure 3 As an alternative to the twisting shown, a change in the channel cross section can also be achieved by moving the valve body 30 relative to the valve sleeve 20. The twisting of the valve body 30 takes place about an axis of rotation, which also defines the longitudinal extension of the regulating valve 10; when the valve body 30 moves in the valve sleeve 20, the movement direction is the longitudinal extension of the regulating valve 10.

[0050] To avoid leakage, two sealing rings 25 are arranged on the outer circumference of the valve sleeve 20, which provide a seal relative to the housing or the hydraulic line on both sides of the flow channel 20. In order to rotate or shift the valve body 30 relative to the valve sleeve 20, an adjusting device 50 is arranged on the valve body 30, by which the valve body can be rotated. In the illustrated embodiment, the adjusting device 50 is designed as a shaft, which is coupled to a drive or a manually operable adjusting element or adjusting wheel. The adjustment can be carried out manually or also by a motor drive, which is preferably controlled by a control device based on sensors in order to adjust the hydraulic resistance according to the sensor data.

[0051] A cavity 31 is formed in the valve body 30, which cavity is cylindrical in the illustrated embodiment. A diffuser insert 40 is arranged in the cavity 31, which is arranged in a rotationally fixed manner and in a non-displaceable manner in the longitudinal extension of the valve body 30. The end of the valve body 30 opposite the outlet 3 is sealed, in particular by the diffuser insert 40. For this purpose, the diffuser insert 40 has a substantially cylindrical end piece, which fits in the cavity 31. The cylindrical end piece extends almost to the diffuser opening 34, which in the illustrated embodiment is located on the same circumferential area, which is also located between the sealing rings as the inlet opening 24. In the illustrated embodiment, the diffuser insert 40 is designed as a separate component, which is inserted and fixed in the valve body 30. As an alternative to a multi-component design, the diffuser insert 40 can also be formed integrally with the valve body 30, or can be manufactured using additive manufacturing processes, or can also be separated from corresponding solid materials using corresponding processes.

[0052] The diffuser insert 40 tapers from its rear end closing the cavity 31 in the direction of the outlet 30 and has a rounded shape, so that the hydraulic fluid flowing radially from the outside through the inlet opening 24 and the channel opening 34 is turned by the diffuser insert at 90° in the direction of the outlet opening 37 of the cavity 31. The change in the surface shape of the diffuser insert 31 in the direction of the outlet opening 37 increases the flow cross section in the area of ​​the cavity 31 formed between the inner wall of the valve body 30 and the diffuser insert 40. The rounded surface shape and the curvature in the direction of the outlet opening 37 and the gradually increasing flow cross section turn the flow direction and slow down the flow speed, thereby avoiding or at least reducing turbulence inside the hydraulic fluid.

[0053] The regulating valve 10 has a plurality of passage openings 34 and inlet openings 24, which are radially arranged around the valve sleeve 20 and the valve body 30, preferably arranged at equal intervals. Therefore, a relatively large amount of hydraulic fluid can be allowed to enter the cavity 31 through the plurality of passage openings 34. In such an embodiment with a plurality of inlet openings 24 and passage openings 34, partition walls 44, 45, 46 are preferably arranged in the region of the passage openings 34, which are arranged at Figure 4 4 is shown in a perspective view of the diffuser insert 40 . Figure 4The diffuser insert 40 in the embodiment of the present invention is an integrally formed molded part having three partition walls 44, 45 and 46 which, in the installed state, extend in the valve body 30 up to the inner wall of the cavity 31. In the case of a cylindrical design of the cavity 31, the partition walls 44, 45, 46 extend in a straight line from the rear end of the diffuser insert 40 in the direction of the outlet 3 or the outlet opening 37. Between the rear walls 44, 45, 46, a groove-shaped, rounded flow surface is formed in each case, which extends radially inwards from the outer circumference of the valve body 40 in the direction of the central body 47. The central body 47 is conical and tapers in the direction of the outlet opening 37. The central body 47 preferably ends in front of the outlet opening 37, so that the entire cross section of the cavity 31 is available in the region of the outlet opening 37 as a flow cross section for the hydraulic fluid. The partition walls 44 , 45 , 46 end in front of the tip of the central body 47 , wherein rounded transitions are provided both between the grooves between the partition walls 44 , 45 and 46 and also radially inwards in order to avoid turbulence in the hydraulic fluid.

[0054] A groove is formed at the rear end of the diffuser insert 40 as an anti-rotation lock, which can be engaged with a protrusion in the valve body 30 in a form-fitting manner.

[0055] Figure 5 A cross-sectional view of two regulating valves 10 is shown, which are arranged in parallel with each other and open to a common outlet 3. The hydraulic fluid can be conveyed from the outlet 3 to the respective chambers of the hydraulic actuator via the non-return valve. In principle, the reverse movement of the hydraulic fluid can also be allowed without the use of a non-return valve.

[0056] Figure 6 A variant of a diffuser insert 40 is shown. This diffuser insert 40 also has three partition walls 44, 45, 46 which are oriented evenly distributed relative to one another on the circumference so that the center planes of the partition walls 44, 45, 46 are at an angle of 120° to one another. An anti-rotation lock 48 as well as an axial lock 49 are formed at the rear end of the diffuser insert 40, which prevent the diffuser insert 40 from shifting and twisting within the valve body 30.

[0057] Figure 7 Show Figure 6 4 is a rear view of the diffuser insert 40. The figure also shows the anti-rotation lock 48 and the axial lock 49 at the rear end, as well as the design as a hollow body and the flow surface extending forward with a certain curvature in the direction of the tip of the central body 47, so that the diffuser insert 40 tapers in the flow direction from the inlet 2 to the outlet 3. The partition walls 44, 45, 46 also taper in the direction of the tip of the central body 47 and preferably have a curved profile.

[0058] Figure 8 A cross-sectional view of the valve body 30 is shown with an inserted Figure 6 and Figure 7The diffuser insert 40 is shown. The outer circumference of the partition wall rests on the inner wall of the valve body 30, and the partition wall 46 is shown to rest on the inner wall of the cavity 31. Between the other two partition walls, the passage opening 34 is arranged inside the valve body wall 32, so that three mutually separated inflow areas are formed in the cavity 31 by the partition walls 44, 45, 46. The hydraulic flow flowing radially from the outside through the passage opening 34 is turned 90° on the surface of the diffuser insert 40 and flows along the tapering center body 47 to the outlet opening.

[0059] Fig. 9 An exploded view of a regulating valve is shown, which comprises three main components: a valve sleeve 20, a valve body 30 and a diffuser insert 40. The valve sleeve 20 is cylindrical and has a substantially closed sleeve wall 22, in which inlet openings 24 are arranged uniformly around the circumference with a 120° offset. In the illustrated embodiment, the inlet opening 24 is formed by two partial openings, which are designed as curved slits. The direction of the slits is at an angle to the longitudinal extension of the valve sleeve 20; alternatively, they can also be formed linearly and at an angle to the longitudinal extension. In the valve sleeve 20, the receiving space 23 is designed as a cylindrical shell and receiving space for the valve body 30. The inlet opening 24 penetrates the sleeve wall 22, so that the fluid can pass through the inlet opening 24 and through the sleeve wall 22 in the direction of the receiving space 23 to the valve body 30.

[0060] In the embodiment shown, the valve body 30 also has a cylindrical outer circumference. The valve body 30 is constructed as a sleeve-like insert by means of a valve body wall 32, in which three passage openings are arranged one after the other in the circumferential direction in the sleeve wall 32 offset by 120°. In the embodiment shown, the passage openings, of which only one passage opening 34 can be seen, are designed as linear slits extending along the longitudinal extension of the valve body 30. The valve body 30 forms a cavity 31 with an outlet opening 37. On the outside of the valve body 30, at the rear end opposite the outlet opening 37, a form-fitting element 38 is arranged as a stop limiter to limit twisting in the valve sleeve 20.

[0061] Similar to the diffuser insert described above, the diffuser insert 40 is designed with three partition walls 44, 45, 46 and is arranged in a torsionally rigid and axially immovable manner in the cavity 31 of the valve body 30. All components of the regulating valve 10 are coaxially oriented and nested in one another. As an alternative to arranging the passage opening 34 as a linear slot extending in the longitudinal direction of the valve body 30, it can also be arranged on the circumference of the valve body wall 33 obliquely with respect to the longitudinal extension. This design can be similar to the outlet opening 34 on the sleeve wall 22 of the valve sleeve 20. The inlet opening 24 can also be designed as a longitudinal slot. It is also possible to design both the inlet opening 24 and the passage opening 34 as Fig. 9The appearance of the inlet opening 24 shown, the size, shape and orientation thereof must ensure that the openings do not overlap to completely close the regulating valve. In order to move to the open position, the valve body 30 must be twisted relative to the valve sleeve 20 until the openings have the maximum degree of overlap.

[0062] Fig.10 and Fig.11 The regulating valve is shown in the open position. Fig.10 A longitudinal section and a cross section are shown, wherein the valve sleeve 20 is indicated by a broken line. Fig.11 The perspective view shows the maximum passage opening, which is achieved by the passage opening 34 covering the entire width of the inlet opening 24. A guide channel 28 is formed in the valve sleeve 20, in which the interest-matching element 38 of the valve body 30 is guided. Fig.10 The right-hand figure shows the maximum open position, in which the form-fit element 38 rests on the end of the guide 28. Fig.11 , it can be seen that the front end of the central body 47 ends shortly before the end of the outlet opening 37 of the cavity 31 of the valve body 30. The hydraulic fluid flowing in radially from the outside is deflected in the direction of the diffuser insert 40 via the overlap of the inlet opening 24 and the passage opening 34, where it strikes the curved surface between the partition walls 44, 45 and is then deflected in the direction of the outlet opening 37. The direct meeting of the hydraulic fluid partial flows entering through the passage opening 34 is achieved by the complete hydraulic separation of the partition walls 44, 45, 46, wherein the partition walls 44, 45, 46 preferably extend to the end of the passage opening 34.

[0063] Fig.12 The hydraulic fluid enters the cavity 31 radially from the outside through the inlet opening 24 and the outlet opening 34 and is deflected at the surface of the diffuser insert 40 and deflected by 90° in the direction of the outlet opening 37 .

[0064] Fig.13 Show Fig. 9 The cross-sectional view of the control valve 10 in the assembled state is shown. Three inlet openings 24, 25, 26 are evenly distributed on the circumference and are connected to the flow channel or inlet in terms of flow technology. The hydraulic fluid flows into the cavity 31 through the inlet openings 24, 25, 26 and the channel openings 34, 35, 36 of the valve body 30 that are oriented accordingly. The partial flow of the hydraulic fluid meets the valve body 40 and is blocked by the partition wall in the inflow area to avoid direct encounter. The channels formed by the partition wall converge in the direction of the outlet opening 37, so that a common fluid flow of the hydraulic fluid is applied at the outlet opening 37.

[0065] Fig.14 and Fig.15 The control valve is shown in the closed position. Its structure basically corresponds to Fig.11 and 10 From Fig.15 As can be seen in FIG. 1 , the form-fit element 38 is twisted in the guide in the valve sleeve until it reaches an opposing stop. The valve body 30 is thus moved from the open position to the illustrated closed position, in which there is no overlap between the inlet opening 24 and the passage opening 34. Apart from any leakage that may exist, which can be minimized or eliminated by reducing the gap width, no hydraulic fluid can flow from the outside through the inlet opening 24 and the passage opening 34.

[0066] Fig.16 A variant of the regulating valve 10 is shown; here too, a valve sleeve 20 is shown, which has a valve body 30 arranged rotatably therein and a diffuser insert 40 arranged in a rotationally fixed manner and axially fastened therein. The difference from the previous embodiment lies in the geometry and design of the inlet opening 24 and the passage opening 34. Here too, three inlet openings and three passage openings are provided, but a design with only two inlet openings and passage openings or more than three inlet openings and passage openings can also be selected, and if necessary, a design with only one inlet opening and one passage opening can also be selected.

[0067] In the illustrated embodiment, the inlet opening 24 is formed as a slot which is formed obliquely relative to the longitudinal extension of the regulating valve in the wall of the valve body 30 and the valve sleeve 20. The inclination of the inlet opening 24 and the inclination of the passage opening 34 are in opposite directions, so that when rotating from the open position shown to the Fig.18 and 19 In the embodiment shown in the figures, the width of the slot increases continuously from the rear end to the front end facing the outlet 37, because the flanks of the slot are not parallel to each other, but separate from the back to the front in the direction of the outlet 37.

[0068] exist Fig.18 and 19 In the embodiment, the valve sleeve 20 and the valve insert 30 are in an almost closed position. Fig.16 Compared to the arrangement shown, the free passage cross section obtained due to the overlap of the inlet opening 24 and the passage opening 34 is reduced. The point at which the hydraulic fluid enters the cavity 31 of the valve body 30 moves from approximately the center of the valve body 30 to the rear end in the direction of the shoulder of the diffuser insert, which rests on the inside of the cavity 31 of the valve body 30. Fig.19 The arrow in the figure indicates the direction in which the free passage cross section moves toward the cavity 31 when the valve body 30 rotates downward. Then, the free passage cross section moves downward and forward from the rear position. Due to the forward movement of the free passage cross section position, the path of the hydraulic fluid from the passage opening to the surface of the diffuser insert 40 becomes larger, thereby optimizing the steering. Fig.18 and19 As shown, due to the reduced channel cross section, a reduced volume flow can enter the cavity closer to the surface of the diffuser insert 40 and flow through the channel between the partition walls to the outlet 37 .

[0069] Fig. 20 Show Figures 16 to 19 The inlet opening in the valve sleeve 20 is not shown, relative to which the passage opening 34 moves during a corresponding rotation, wherein the free passage cross sections of the overlapping inlet opening and passage opening move not only in the circumferential direction but also in the axial direction. Fig.18 and 19 In the position shown, the hydraulic fluid continues to enter the cavity 31 at the rear end, which is indicated by the longer rear arrow. Fig.16 and 17 In the open position shown, a greater volume flow passes through the free passage cross section of the inlet opening and the passage opening, which is indicated by the thicker front arrow.

[0070] By adjusting or twisting the overlap of the inlet opening and the channel opening, the free channel cross section and the flow of the hydraulic fluid entering the cavity are shifted along the longitudinal extension in the direction of the diffuser insert 40. Depending on the relative position of the valve sleeve 20 and the valve body 30, the axial position of the free channel cross section and the position of the inflowing hydraulic fluid change. The diffuser insert 40 is shaped so as to achieve a flow-technically optimal flow, so that when flowing into the regulating valve, almost no turbulence or only slight turbulence occurs.

Claims

1. A hydraulic actuator for an orthopaedic device, comprising a regulating valve (10) in a flow channel (1), the flow channel having an inlet (2) and an outlet (3) for a hydraulic fluid, The regulating valve (10) comprises a valve sleeve (20) and a valve body (30). The valve sleeve (20) has a sleeve wall (22) which forms a receiving space (23) and in which at least one radially oriented inlet opening (24, 25, 26) is formed. The valve body (30) is arranged in a receiving space (23) of the valve sleeve (20) so as to be movable between a closed position and an open position and opens into the outlet (3). The valve body (30) has at least one valve body wall (32) which is opposite the at least one inlet opening (24, 25, 26) and in which a passage opening (34, 35, 36) is formed, which passage opening is opposite the corresponding inlet opening (24, 25, 26) in the open position, It is characterized in that The valve body (30) forms a cavity (31) in which a diffuser insert (40) is arranged, which deflects the hydraulic fluid in the direction of the outlet (3).

2. The hydraulic actuator according to claim 1, characterized in that: Apart from at least one passage opening (34, 35, 36) and an outlet opening (37), the cavity (31) is designed to be closed.

3. The hydraulic actuator according to claim 1 or 2, characterized in that: The diffuser insert (40) is manufactured separately from the valve body (30) and is fastened to or in the valve body (30), or is an integral component of the valve body (30).

4. Hydraulic actuator according to one of the preceding claims, characterized in that The valve body (30) has a plurality of passage openings (34, 35, 36) and the diffuser insert (40) has partition walls (44, 45, 46) which are arranged between the passage openings (34, 35, 36).

5. The hydraulic actuator according to claim 4, characterized in that: The partition walls (44, 45, 46) extend to the outlet (3) or end before the outlet.

6. Hydraulic actuator according to one of the preceding claims, characterized in that The valve body (30) is supported in the valve sleeve (20) in a rotatable or displaceable manner.

7. Hydraulic actuator according to one of the preceding claims, characterized in that The valve body (30) is coupled to the regulating device (50).

8. Hydraulic actuator according to one of the preceding claims, characterized in that The diffuser insert (40) is designed to taper in the direction of the outlet (3).

9. Hydraulic actuator according to one of the preceding claims, characterized in that The valve sleeve (20) is designed as a part of the housing (4) or as a separate component.

10. Hydraulic actuator according to one of the preceding claims, characterized in that The inlet (2) and the outlet (3) are fluidically connected to the piston-cylinder unit (300) and to the two chambers separated by the piston.

11. Hydraulic actuator according to one of the preceding claims, characterized in that The inlet opening (24, 25, 26) and / or the passage opening (34, 35, 36) are configured as slots oriented obliquely with respect to the longitudinal extension of the regulating valve (10).

12. The hydraulic actuator according to claim 11, characterized in that: The slot is designed to be straight or curved and / or varies in width along its longitudinal extension.

13. A regulating valve according to any one of the preceding claims.

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