CN111365305A

CN111365305A - Knee joint prosthesis, hydraulic damper for prosthesis and energy storage acting method of knee joint prosthesis

Info

Publication number: CN111365305A
Application number: CN202010304725.5A
Authority: CN
Inventors: 金坤锋; 李哲; 梁燕平; 冯琴琴; 申骏军; 谢浩; 玄利圣; 韩毓
Original assignee: Huzhou Institute Of International Innovation Harbin University Of Technology Robot
Current assignee: Zhenxing Technology (Huzhou) Co.,Ltd.
Priority date: 2020-04-17
Filing date: 2020-04-17
Publication date: 2020-07-03

Abstract

The invention provides a knee joint prosthesis, a hydraulic damper for a prosthesis and an energy storage acting method of the knee joint prosthesis. A hydraulic damper for a prosthesis comprising: a hydraulic cylinder block; the energy accumulator is arranged on the hydraulic cylinder body, a first port of the energy accumulator is communicated with the rod cavity through a first pipeline, the first port of the energy accumulator is communicated with the rodless cavity through a second pipeline, and the second pipeline comprises a first branch pipeline and a second branch pipeline which are arranged in parallel; the first check valve is arranged on the first branch pipeline, the second check valve is arranged on the second branch pipeline, and the control directions of the first check valve and the second check valve are opposite; the first control valve is installed on the first branch pipeline, and the second control valve is installed on the second branch pipeline. The invention can reduce the volume and the mass of the whole damper, has simple structure and further reduces the production cost of the hydraulic damper for the artificial limb.

Description

Knee joint prosthesis, hydraulic damper for prosthesis and energy storage acting method of knee joint prosthesis

Technical Field

The invention relates to the technical field of artificial limb components, in particular to a knee joint prosthesis, a hydraulic damper for an artificial limb and an energy storage acting method of the knee joint prosthesis.

Background

The hydraulic damper of the artificial limb mainly comprises a single-rod double-acting hydraulic cylinder, three throttle valves, a one-way valve, a spring accumulator and an oil tank.

As shown in fig. 1, the conventional single-rod double-acting cylinder hydraulic damper operates as follows:

a) in stage one, the throttle valve 1 is opened, the throttle valve 2 and the throttle valve 3 are closed, and the piston rod moves downwards under the action of external force. At the moment, the single-rod double-acting hydraulic cylinder forms differential connection, hydraulic fluid passes through the throttling valve 1 from the rodless cavity, one part of the hydraulic fluid enters the rod cavity, and the hydraulic fluid and part of the hydraulic fluid enter the spring accumulator through the one-way valve; the accumulator stores energy at this stage.

b) And in the second stage, the throttle valve 1 and the throttle valve 3 are closed, the throttle valve 2 is opened, and the piston rod moves upwards under the action of external force. At the moment, hydraulic fluid in the oil tank enters the rodless cavity through the throttle valve 2, and hydraulic fluid in the rod cavity enters the spring accumulator through the one-way valve; the accumulator stores energy at this stage.

c) And stage three, closing the throttle valve 1, and opening the

throttle valves

2 and 3. At the moment, high-pressure hydraulic fluid in the spring energy accumulator enters the rodless cavity through the throttle valve 3 to push the piston rod to move downwards, and the hydraulic fluid in the rodless cavity enters the oil tank through the throttle valve 2; the accumulator does work at this stage.

d) And stage four, opening the throttle valve 1 and the throttle valve 3, and closing the throttle valve 2. At the moment, the single-rod double-acting hydraulic cylinder forms differential connection, part of high-pressure hydraulic fluid in the spring accumulator enters a rod cavity through the throttle valve 3, and part of the hydraulic fluid enters a rodless cavity through the throttle valve 1. Because the area of the rodless cavity is larger than that of the oil cylinder cavity, the piston rod moves upwards; the accumulator does work at this stage.

According to the structure, the prior single-rod double-acting cylinder hydraulic damper has the following defects:

(1) the single-rod double-acting cylinder hydraulic damper is provided with three throttle valves, and three sets of devices for adjusting the opening degree or opening and closing of the throttle valves are needed, so that the hydraulic damper is bulky in structure, large in mass and high in cost. The hydraulic oil tank always needs low pressure or is communicated with the atmosphere, and the oil tank can not suck air when rotating at any angle. Therefore, the hydraulic oil tank meeting the above conditions has the advantages of complex structural design, overstaffed appearance, large mass and high cost. However, the artificial limb worn by the patient has the advantages of simple and reliable structure, small mass and low cost, which are always the priority targets.

(2) In stages three and four, i.e. the accumulator work stage, the hydraulic accumulator cannot prevent the reverse movement of the piston rod. In the field of artificial limbs, under the action of external force, a piston rod which plays a supporting role moves reversely, and accidental injury can be caused to a patient. The reverse movement here refers to the following conditions:

in the third stage, the energy accumulator does work, and the piston rod moves downwards; at this time, the piston rod is moved upward by an external force actually downward, and when the external force is larger than the driving force of the energy accumulator.

In the fourth stage, the energy accumulator works, and the piston rod moves upwards; at this time, the piston rod is moved downward by an external force actually applied upward to the piston rod when the external force is larger than the driving force of the accumulator.

Disclosure of Invention

The invention mainly aims to provide a knee joint prosthesis, a hydraulic damper for an artificial limb and an energy storage acting method thereof, and aims to solve the problems of overstaffed appearance, large mass and high cost of the hydraulic damper for the artificial limb in the prior art.

In order to achieve the above object, according to one aspect of the present invention, there is provided a hydraulic damper for a prosthesis, comprising: the hydraulic cylinder body is provided with a cavity, a piston and a piston rod connected to the piston are installed in the cavity, and the cavity is divided into a rod cavity and a rodless cavity by the piston; the energy accumulator is arranged on the hydraulic cylinder body, a first port of the energy accumulator is communicated with the rod cavity through a first pipeline, the first port of the energy accumulator is communicated with the rodless cavity through a second pipeline, and the second pipeline comprises a first branch pipeline and a second branch pipeline which are arranged in parallel; the first check valve is arranged on the first branch pipeline, the second check valve is arranged on the second branch pipeline, and the control directions of the first check valve and the second check valve are opposite; the first control valve is installed on the first branch pipeline, and the second control valve is installed on the second branch pipeline.

Further, both ends of the first control valve are respectively communicated with the rodless chamber and the first check valve, and the first check valve is used for enabling the hydraulic liquid in the first control valve to flow towards the accumulator.

Further, both ends of the second control valve are respectively communicated with the second check valve and the accumulator, and the second check valve is used for enabling the hydraulic liquid in the second control valve to flow towards the direction of the rodless cavity.

Further, the first control valve and the second control valve are both throttle valves.

Further, the second one-way valve is installed at the bottom of the rodless cavity, and the first one-way valve is installed on one side, far away from the piston rod, of the second one-way valve.

Further, the hydraulic damper for a prosthesis further includes a mount housing mounted on an outer side wall surface of the hydraulic cylinder body, and the first control valve is mounted inside the mount housing.

Further, the second control valve is mounted within the mounting housing and is positioned alongside the first control valve.

Further, the mounting housing is fixed to the hydraulic cylinder body by a locking member or a welding method.

According to another aspect of the present invention, there is provided a knee joint prosthesis comprising a hydraulic damper as described above for a prosthesis.

According to a third aspect of the present invention, there is provided an energy-storing work-doing method for a hydraulic damper of a prosthesis, which is implemented by using the above-mentioned hydraulic damper for a prosthesis, and comprises: and (3) energy storage working stage: opening the first control valve, closing the second control valve, and compressing the piston rod by external force to realize downward movement of the piston rod; at this time, after the hydraulic fluid in the rodless cavity passes through the first control valve and the first check valve, one part of the hydraulic fluid enters the rod cavity, and the rest part of the hydraulic fluid enters the energy accumulator, so that the energy accumulation of the energy accumulator is realized; in the energy storage working stage, the action direction of external force is changed, the piston rod is stretched outwards, and the piston rod cannot stretch out; working stage of doing work: closing the first control valve, opening the second control valve, allowing high-pressure hydraulic fluid in the accumulator to pass through the second control valve and the second check valve and enter the rodless chamber, moving the piston rod upwards, and allowing all of the hydraulic fluid in the rod chamber and the high-pressure hydraulic fluid in the accumulator to enter the rodless chamber; in the working stage, an external force opposite to the movement direction of the piston rod is applied to the piston rod, namely, the piston rod is compressed, and the piston rod cannot retract.

Compared with the existing single-rod double-acting cylinder hydraulic damper structure, the whole system does not comprise an oil tank, and only comprises two control valves, so that the volume and the mass of the whole damper can be reduced, the structure is simple, and the production cost of the hydraulic damper for the artificial limb is further reduced.

The hydraulic damper for the artificial limb is more stable and reliable in structure. The reverse movement can be completely inhibited under the action of an external force. That is, in the retraction stage of the piston rod, no matter which direction of external force is applied to the piston rod, the piston rod will not extend out; in the extension stage of the piston rod, no matter which direction of external force is applied to the piston rod, the piston rod cannot retract.

In addition to the objects, features and advantages described above, other objects, features and advantages of the present invention are also provided. The present invention will be described in further detail below with reference to the drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 schematically illustrates a prior art single rod double acting cylinder hydraulic damper schematic;

FIG. 2 schematically illustrates a schematic diagram of the hydraulic damper for a prosthesis of the present invention;

fig. 3 schematically shows an exploded view of the hydraulic damper for a prosthesis of the present invention.

Wherein the figures include the following reference numerals:

10. a hydraulic cylinder block; 11. a rodless cavity; 12. a rod cavity; 20. a piston; 30. a piston rod; 40. an energy storage device; 50. a first pipeline; 51. a first branch conduit; 52. a second branch conduit; 60. a second pipeline; 61. a first branch conduit; 62. a second branch conduit; 70. a first check valve; 80. a second one-way valve; 90. a first control valve; 100. a second control valve; 110. and (5) installing the shell.

Detailed Description

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances for describing embodiments of the invention herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

Referring to fig. 2 and 3, according to an embodiment of the present invention, a hydraulic damper for a prosthesis is provided. The hydraulic damper for a prosthesis in the present embodiment includes a hydraulic cylinder 10, an accumulator 40, a first check valve 70, a second check valve 80, a first control valve 90, and a second control valve 100.

Wherein, the hydraulic cylinder 10 is provided with a cavity, the cavity is internally provided with a piston 20 and a piston rod 30 connected with the piston 20, and after the hydraulic cylinder is assembled, the piston 20 divides the cavity into a rod cavity 12 and a rodless cavity 11; the accumulator 40 is mounted on the hydraulic cylinder 10, and a first port of the accumulator 40 is communicated with the rod chamber 12 through a first pipeline 50, and a first port of the accumulator 40 is communicated with the rodless chamber 11 through a second pipeline 60, wherein the second pipeline 60 in the embodiment comprises a first branch pipeline 61 and a second branch pipeline 62 which are arranged in parallel; a first check valve 70 is provided on the first branch pipe 61, a first end of the first branch pipe 61 communicates with the rodless chamber 11, a second end of the first branch pipe 61 communicates with the first port of the accumulator 40, a second check valve 80 is provided on the second branch pipe 62, a first end of the second branch pipe 62 communicates with the rodless chamber 11, a second end of the second branch pipe 62 communicates with the first port of the accumulator 40, and control directions of the first check valve 70 and the second check valve 80 are opposite; a first control valve 90 is installed on the first branch duct 61, and a second control valve 100 is installed on the second branch duct 62.

Compared with the existing single-rod double-acting cylinder hydraulic damper structure, the whole system does not comprise an oil tank, only comprises two control valves, can reduce the volume and the mass of the whole damper, is simple in structure, and further reduces the production cost of the hydraulic damper for the prosthesis in the embodiment.

In actual operation, the hydraulic damper for the artificial limb in the embodiment has an energy storage working stage and a working stage.

In particular, when the hydraulic damper for a prosthesis is in the charging phase: opening the first control valve 90 and closing the second control valve 100, the piston rod 30 is compressed by external force to realize downward movement of the piston rod 30; at this time, after the hydraulic fluid in the rodless chamber 11 passes through the first control valve 90 and the first check valve 70, a part of the hydraulic fluid enters the rod chamber 12 from the first pipeline 50, and the rest of the hydraulic fluid enters the accumulator 40, so that the accumulator 40 accumulates energy; in this working phase, the direction of the external force is changed, the piston rod 30 is pulled outward, and the piston rod 30 does not extend.

When the hydraulic damper for the prosthesis is in the working stage of doing work: closing the first control valve 90, opening the second control valve 100, allowing the high pressure hydraulic fluid in the accumulator 40 to pass through the second control valve 100 and the second check valve 80, and enter the rodless chamber 11 from the second branch conduit 62, and since the surface area of the piston 20 on the side of the rodless chamber 11 is larger than the surface area on the side of the rod chamber 12, the piston rod 30 moves upward, and the hydraulic fluid in the rod chamber 12 and the high pressure hydraulic fluid in the accumulator 40 all enter the rodless chamber 11; in this working phase, an external force opposite to the movement direction of the piston rod 30 is applied to the piston rod 30, i.e., the piston rod 30 is compressed, and the piston rod 30 is not retracted.

It can be seen that the hydraulic damper for a prosthesis in this embodiment is more stable and reliable in structure. The reverse movement can be completely inhibited under the action of an external force. That is, in the retraction stage of the piston rod 30, the piston rod 30 does not extend regardless of the direction of the external force applied to the piston rod 30; in the extending stage of the piston rod 30, the piston rod 30 is not retracted regardless of the direction of the external force applied to the piston rod 30.

In practice, the first control valve 90 in this embodiment is connected at both ends to the rodless chamber 11 and the first check valve 70, respectively, and the first check valve 70 is used to allow the hydraulic fluid in the first control valve 90 to flow toward the accumulator 40. Correspondingly, both ends of the second control valve 100 are in communication with the second check valve 80 and the accumulator 40, respectively, the second check valve 80 being adapted to allow hydraulic fluid in the second control valve 100 to flow in the direction of the rodless chamber 11.

Of course, in other embodiments of the present invention, the control directions of the first check valve 70 and the second check valve 80 may be reversed, and any other modifications within the spirit of the present invention are within the scope of the present invention.

Preferably, the first control valve 90 and the second control valve 100 in this embodiment are both throttles, which are simple in structure and facilitate the control of the hydraulic fluid inside the damper. Of course, in other embodiments of the present invention, the first control valve 90 and the second control valve 100 may be configured as other types of on-off valves, and any other modifications under the concept of the present invention are within the protection scope of the present invention.

The second check valve 80 is arranged at the bottom of the rodless cavity 11, and the first check valve 70 is arranged at one side of the second check valve 80, which is far away from the piston rod 30, so that the whole structure is more compact, and the size of the damper is further reduced.

Referring again to fig. 3, the hydraulic damper for a prosthesis in the present embodiment further includes a mounting housing 110, the mounting housing 110 being mounted on an outer side wall surface of the hydraulic cylinder 10, the first control valve 90 being mounted inside the mounting housing 110, and the second control valve 100 being mounted inside the mounting housing 110 and being arranged side by side with the first control valve 90.

In the present embodiment, the first control valve 90 and the second control valve 100 are fixed to the outer wall surface of the cylinder block 10 by the same mounting case 110, and the volume of the damper can be further reduced.

In practice, the mounting housing 110 of the present embodiment may be fixed to the cylinder body 10 by a locking member, or may be fixed to the cylinder body 10 by welding, and any other modifications within the spirit of the present invention are within the scope of the present invention. Preferably, the locking member in this embodiment may be a screw, a bolt, a snap, or the like.

According to another aspect of the invention, an energy storage and work doing method for a hydraulic damper of a prosthesis is provided, and the energy storage and work doing method for the hydraulic damper of the prosthesis in the embodiment is realized by adopting the hydraulic damper for the prosthesis in the embodiment.

Specifically, the energy storage working method for the hydraulic damper for the prosthesis in the embodiment includes an energy storage working stage and a working stage, and when the hydraulic damper for the prosthesis is in the energy storage working stage: opening the first control valve 90 and closing the second control valve 100, the piston rod 30 is compressed by external force to realize downward movement of the piston rod 30; at this time, after the hydraulic fluid in the rodless chamber 11 passes through the first control valve 90 and the first check valve 70, a part of the hydraulic fluid enters the rod chamber 12 from the first pipeline 50, and the rest of the hydraulic fluid enters the accumulator 40, so that the accumulator 40 accumulates energy; in this working phase, the direction of the external force is changed, the piston rod 30 is pulled outward, and the piston rod 30 does not extend. When the hydraulic damper for the prosthesis is in the working stage of doing work: closing the first control valve 90, opening the second control valve 100, allowing the high pressure hydraulic fluid in the accumulator 40 to pass through the second control valve 100 and the second check valve 80, and enter the rodless chamber 11 from the second branch conduit 62, and since the surface area of the piston 20 on the side of the rodless chamber 11 is larger than the surface area on the side of the rod chamber 12, the piston rod 30 moves upward, and the hydraulic fluid in the rod chamber 12 and the high pressure hydraulic fluid in the accumulator 40 all enter the rodless chamber 11; in this working phase, an external force opposite to the movement direction of the piston rod 30 is applied to the piston rod 30, i.e., the piston rod 30 is compressed, and the piston rod 30 is not retracted.

According to another embodiment of the present invention, there is provided a knee joint prosthesis comprising a hydraulic damper for a prosthesis in the above-described embodiment.

From the above description, it can be seen that the above-described embodiments of the present invention achieve the following technical effects:

the whole system of the hydraulic damper for a prosthesis of the present invention does not contain an oil tank and the number of throttle valves is as small as possible.

The hydraulic damper for the artificial limb of the invention adopts a differential connection mode for a single-rod double-acting hydraulic cylinder to realize the function of a single-acting piston cylinder, and is convenient for adding a cylinder buffer structure.

The hydraulic damper for a prosthesis of the present invention is a hydraulic damper system. In the energy storage stage, the piston rod is compressed by external force, the piston rod retracts, and the system stores energy; in the working stage, the energy accumulator releases energy to push the piston rod to extend out.

The piston rod of the hydraulic damper for the artificial limb does not move reversely under the action of external force. The reverse movement here refers to the following conditions: in the stage that the piston rod retracts into the oil cylinder, the piston rod is pulled outwards by external force, and cannot extend out; in the piston rod extending stage, the piston rod is compressed by external force and can not retract.

The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

In the description of the present invention, it is to be understood that the orientation or positional relationship indicated by the orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc. are usually based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and in the case of not making a reverse description, these orientation words do not indicate and imply that the device or element being referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore, should not be considered as limiting the scope of the present invention; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A hydraulic damper for a prosthetic limb, comprising:

the hydraulic cylinder comprises a hydraulic cylinder body (10), wherein a cavity is formed in the hydraulic cylinder body (10), a piston (20) and a piston rod (30) connected to the piston (20) are installed in the cavity, and the cavity is divided into a rod cavity (12) and a rodless cavity (11) by the piston (20);

the energy accumulator (40) is mounted on the hydraulic cylinder body (10), a first port of the energy accumulator (40) is communicated with the rod cavity (12) through a first pipeline (50), a first port of the energy accumulator (40) is communicated with the rodless cavity (11) through a second pipeline (60), and the second pipeline (60) comprises a first branch pipeline (61) and a second branch pipeline (62) which are arranged in parallel;

a first check valve (70) and a second check valve (80), wherein the first check valve (70) is arranged on the first branch pipeline (61), the second check valve (80) is arranged on the second branch pipeline (62), and the control directions of the first check valve (70) and the second check valve (80) are opposite;

a first control valve (90) and a second control valve (100), the first control valve (90) being mounted on the first branch conduit (61), the second control valve (100) being mounted on the second branch conduit (62).

2. A hydraulic damper for a prosthesis according to claim 1, wherein both ends of said first control valve (90) communicate with said rodless chamber (11) and said first check valve (70), respectively, said first check valve (70) being adapted to allow hydraulic fluid in said first control valve (90) to flow in a direction toward said accumulator (40).

3. A hydraulic damper for a prosthesis according to claim 1, wherein both ends of said second control valve (100) communicate with said second check valve (80) and said accumulator (40), respectively, said second check valve (80) being adapted to allow hydraulic fluid in said second control valve (100) to flow in a direction towards said rodless chamber (11).

4. A hydraulic damper for a prosthetic limb according to claim 1, wherein said first control valve (90) and said second control valve (100) are both throttle valves.

5. A hydraulic damper for a prosthesis according to claim 1, wherein said second one-way valve (80) is mounted at the bottom of said rodless chamber (11), and said first one-way valve (70) is mounted on the side of said second one-way valve (80) remote from said piston rod (30).

6. A hydraulic damper for a prosthesis according to claim 1, further comprising a mount housing (110), said mount housing (110) being mounted on an outer side wall surface of said hydraulic cylinder block (10), said first control valve (90) being mounted inside said mount housing (110).

7. A hydraulic damper for a prosthetic limb according to claim 6, wherein said second control valve (100) is mounted within said mounting shell (110) and is located alongside said first control valve (90).

8. A hydraulic damper for a prosthesis according to claim 6, wherein said mounting shell (110) is fixed to said hydraulic cylinder (10) by locking or welding.

9. A knee joint prosthesis comprising a hydraulic damper, wherein the hydraulic damper is as claimed in any one of claims 1 to 8 for a prosthesis.

10. An energy-storing work doing method for a hydraulic damper for a prosthesis, characterized in that the energy-storing work doing method for a hydraulic damper for a prosthesis is implemented by using the hydraulic damper for a prosthesis according to any one of claims 1 to 8, and the energy-storing work doing method for a hydraulic damper for a prosthesis comprises:

and (3) energy storage working stage: opening the first control valve (90), closing the second control valve (100), and compressing the piston rod (30) by external force to realize downward movement of the piston rod (30); at the moment, after the hydraulic liquid in the rodless cavity (11) passes through the first control valve (90) and the first check valve (70), one part of the hydraulic liquid enters the rod cavity (12), and the rest part of the hydraulic liquid enters the energy accumulator (40), so that the energy accumulator (40) can accumulate energy; in the energy storage working stage, the action direction of external force is changed, the piston rod (30) is stretched outwards, and the piston rod (30) cannot stretch out;

working stage of doing work: closing the first control valve (90), opening the second control valve (100), allowing high-pressure hydraulic fluid in the accumulator (40) to pass through the second control valve (100) and the second check valve (80) and enter the rodless chamber (11), moving the piston rod (30) upward, and allowing all of the hydraulic fluid in the rod chamber (12) and the high-pressure hydraulic fluid in the accumulator (40) to enter the rodless chamber (11); in the working stage, an external force opposite to the movement direction of the piston rod (30) is applied to the piston rod (30), namely the piston rod (30) is compressed, and the piston rod (30) cannot retract.