Internal sealing device applied to vane type hydraulic rotary actuator

Abstract

The invention relates to the technical field of mechanical sealing, and particularly discloses an internal sealing device applied to a vane type hydraulic rotary actuator, which comprises an outer cylinder and an inner cylinder, a boss which protrudes inwards is arranged on the inner side of the outer cylinder, an outer cylinder sealing piece is embedded in the middle of the boss on the inner side of the outer cylinder, a boss which protrudes outwards is arranged on the outer side of the inner cylinder, and the outer cylinder sealing piece is embedded in the middle of the boss on the inner side of the outer cylinder. An inner cylinder sealing piece is embedded in the middle of the boss on the outer side of the inner cylinder, the inner cylinder is embedded in the outer cylinder, the outer wall of the inner cylinder abuts against the outer cylinder sealing piece on the inner side of the outer cylinder, the boss of the inner cylinder and the inner wall of the outer cylinder abut against the inner cylinder sealing piece, and therefore the inner cylinder divides the interior of the outer cylinder into two working cavities. According to the rotary actuator, the outer cylinder sealing piece and the inner cylinder sealing piece which are composed of the sealing framework, the elastic piece and the sealing ring are arranged, so that an internal sealing structure exists between two working cavities formed by the blades of the outer cylinder and the blades of the inner cylinder, and the internal sealing performance of the rotary actuator is improved on the basis of mechanical sealing; and the working efficiency of the blade type hydraulic rotary actuator is improved.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical seals, and in particular to an internal sealing device applied to a vane type hydraulic rotary actuator. Background Art

[0002] The vane-type hydraulic rotary actuator is composed of moving parts and stationary parts. Generally, the inner cylinder is the stationary part and the outer cylinder is the moving part. When the actuator in the hydraulic system is a vane-type hydraulic rotary actuator, the system hydraulic pump supplies oil of a certain pressure to the rotary actuator, and the moving parts of the rotary actuator are driven to rotate through the vanes of the rotary actuator, and the rotary actuator outputs the corresponding load. In order to ensure the working efficiency of the hydraulic rotary actuator with a vane-type structure, one of the measures is to improve the internal sealing performance of the rotary actuator, and the internal sealing performance is guaranteed by the internal sealing device. Generally, the internal sealing device of the vane-type hydraulic rotary actuator adopts a mechanical gap seal between the matching surfaces of the vane and the outer cylinder (or inner cylinder).

[0003] The vane-type hydraulic rotary actuator generally has two working chambers. When working, the system hydraulic pump supplies hydraulic oil of a certain pressure to one of the working chambers of the rotary actuator. The pressure oil drives the moving parts of the rotary actuator to rotate through the blades of the rotary actuator, and outputs the corresponding load. Generally, the internal sealing method of the vane-type hydraulic rotary actuator adopts the mechanical gap sealing between the matching surface of the blade and the outer cylinder (or inner cylinder), and there is no special sealing device in the internal sealing part. Because the inner cylinder and the outer cylinder of the rotary actuator need to move smoothly and smoothly, the matching gap between the blade and the outer cylinder (or inner cylinder) cannot be too small. If the matching gap is too small, the friction between the inner cylinder and the outer cylinder will increase, making the relative rotation between the inner cylinder and the outer cylinder sluggish. Therefore, when the internal seal of the vane-type hydraulic rotary actuator adopts the mechanical gap sealing method, the oil flows from the high-pressure chamber to the low-pressure chamber through the matching gap between the blade and the outer cylinder (or inner cylinder) under the drive of pressure, causing the pressure loss of the working oil in the high-pressure chamber, thereby causing a large power loss of the hydraulic system, reducing the working efficiency, and making the theoretical output load of the rotary actuator differ greatly from the actual output load. Summary of the invention

[0004] The object of the present invention is to provide an internal sealing device for a vane-type hydraulic rotary actuator, which can improve the working efficiency of the vane-type hydraulic rotary actuator and has good sealing performance and long service life.

[0005] The present invention is achieved through the following technical scheme: an internal sealing device applied to a blade-type hydraulic rotary actuator, comprising an outer cylinder and an inner cylinder, wherein an inwardly protruding boss is arranged on the inner side of the outer cylinder, an outer cylinder seal is embedded in the middle of the boss on the inner side of the outer cylinder, an outwardly protruding boss is arranged on the outer side of the inner cylinder, an inner cylinder seal is embedded in the middle of the boss on the outer side of the inner cylinder, the inner cylinder is embedded in the outer cylinder, the outer wall of the inner cylinder abuts against the outer cylinder seal on the inner side of the outer cylinder, the boss of the inner cylinder and the inner wall of the outer cylinder abut against the inner cylinder seal, so that the inner cylinder divides the inner side of the outer cylinder into two working chambers.

[0006] The working principle of this technical solution is to design an internal sealing device composed of a sealing frame, an elastomer, and a sealing ring according to the specific structural form of the hydraulic rotary actuator blade structure, so as to improve the internal sealing performance of the rotary actuator on the basis of mechanical sealing.

[0007] In order to better realize the present invention, further, the outer tube seal and the inner tube seal have the same structure, both comprising a rectangular sealing frame, a ring-shaped embedding groove is provided in the middle of the sealing frame, an elastic part is nested in the embedding groove, the elastic part of the outer tube seal abuts against the outer wall of the inner tube, and the elastic part of the inner tube seal abuts against the inner wall of the outer tube.

[0008] In order to better implement the present invention, further, a sealing ring is nested in the groove in the middle of the sealing frame outside the elastic member, the sealing ring of the outer tube seal abuts against the outer wall of the inner tube, and the sealing ring of the inner tube seal abuts against the inner wall of the outer tube.

[0009] In order to better realize the present invention, further, the outer tube seal includes a sealing frame, a ring-shaped embedding groove is arranged in the middle of the sealing frame, an elastic part is nested in the embedding groove, and the side of the sealing frame facing the inner tube is a concave arc surface that fits the outer wall of the inner tube, and the elastic part of the outer tube seal and the concave arc surface of the sealing frame are in contact with the outer wall of the inner tube.

[0010] In order to better implement the present invention, further, a sealing ring is nested outside the elastic member in the embedding groove in the middle of the sealing frame, and the sealing ring of the outer cylinder seal and the concave arc surface of the sealing frame abut against the outer wall of the inner cylinder.

[0011] In order to better implement the present invention, further, a boss protruding inward is provided on the inner side of the outer tube, and a concave arc surface that fits with the outer wall of the inner tube is provided on the side of the boss facing the inner tube, and the sealing ring of the outer tube seal, the concave arc surface of the sealing frame, and the concave arc surface of the boss on the inner side of the outer tube are in contact with the outer wall of the inner tube.

[0012] In order to better realize the present invention, further, the inner tube seal includes a sealing frame, a ring-shaped embedding groove is arranged in the middle of the sealing frame, an elastic part is nested in the embedding groove, and the side of the sealing frame facing the outer tube is a convex arc surface that fits the outer wall of the outer tube, and the elastic part of the inner tube seal and the convex arc surface of the sealing frame are in contact with the inner wall of the outer tube.

[0013] In order to better implement the present invention, further, a sealing ring is embedded in the embedding groove in the middle of the sealing frame outside the elastic member, and the sealing ring of the inner tube seal and the convex arc surface of the sealing frame abut against the inner wall of the outer tube.

[0014] In order to better realize the present invention, further, a boss protruding outward is provided on the outer side of the inner tube, and a convex arc surface is provided on the side of the boss facing the outer tube that fits the outer wall of the outer tube. The sealing ring of the inner tube seal, the convex arc surface of the sealing frame, and the convex arc surface of the boss on the outer side of the inner tube are in contact with the inner wall of the outer tube.

[0015] In order to better realize the present invention, further, the axes of the outer tube and the inner tube coincide with each other, the axis of the boss in the middle of the inner side of the outer tube coincides with the axis of the outer tube, and the axis of the boss in the middle of the outer side of the inner tube coincides with the axis of the inner tube; the groove of the boss in the middle of the inner side of the outer tube coincides with the axis of the outer tube, and the groove of the boss in the middle of the outer side of the inner tube coincides with the axis of the inner tube; the axes of the outer tube seal and the inner tube seal respectively coincide with the axes of the grooves in which they are embedded.

[0016] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0017] According to the specific structural form of the blade structure of the hydraulic rotary actuator, the present invention provides an outer cylinder seal and an inner cylinder seal composed of a sealing frame, an elastic member, and a sealing ring in order to improve the internal sealing performance of the rotary actuator on the basis of a mechanical seal, so that an internal sealing structure exists between the two working chambers formed by the blades of the outer cylinder and the blades of the inner cylinder. By utilizing the effect of the elastic member, the sealing ring is tightly fitted to the surface of the blade and the surface of the sealing frame to prevent the oil in the high-pressure chamber from flowing to the low-pressure chamber, thereby improving the working efficiency of the blade-type hydraulic rotary actuator. In addition, due to the provision of the sealing ring, the internal sealing device is more wear-resistant and has a long service life, and is suitable for wide promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments with reference to the following drawings:

[0019] Figure 1 It is a schematic diagram of the split three-dimensional structure of the present invention;

[0020] Figure 2It is a schematic diagram of the disassembled structure of the outer cylinder seal or the inner cylinder seal in the present invention;

[0021] Figure 3 It is a cross-sectional structural schematic diagram of Example 2 of the present invention;

[0022] Figure 4 It is a schematic diagram of the cross-sectional structure of Example 3 and Example 4 of the present invention.

[0023] Among them: 1 - outer tube, 2 - inner tube, 3 - outer tube seal, 4 - inner tube seal, 5 - sealing frame, 6 - elastic part, 7 - sealing ring. DETAILED DESCRIPTION

[0024] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0025] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0026] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] Embodiment 1:

[0028] The main structure of this embodiment is as follows: Figure 1 , Figure 3 , Figure 4As shown, it includes an outer tube 1 and an inner tube 2, the inner side of the outer tube 1 is provided with a boss protruding inwards, the middle part of the boss inside the outer tube 1 is embedded with an outer tube seal 3, the outer side of the inner tube 2 is provided with a boss protruding outwards, the middle part of the boss outside the inner tube 2 is embedded with an inner tube seal 4, the inner tube 2 is embedded in the outer tube 1, the outer wall of the inner tube 2 abuts against the outer tube seal 3 inside the outer tube 1, the boss of the inner tube 2 and the inner wall of the outer tube 1 abut against the inner tube seal 4, so that the inner tube 2 divides the inner side of the outer tube 1 into two working chambers.

[0029] The specific implementation process is that the inner cylinder 2 of the vane-type hydraulic rotary actuator divides the outer cylinder 1 into two working chambers. When the vane-type hydraulic rotary actuator is working, the system hydraulic pump supplies oil with a certain pressure to one of the working chambers of the rotary actuator. The pressurized oil completely fills the working chamber. When the oil in the working chamber establishes an internal pressure value that can overcome the load, the hydraulic pressure drives the blades of the rotary actuator to rotate, the moving parts of the rotary actuator start to move, and the rotary actuator outputs the corresponding load.

[0030] The contact parts between the outer cylinder seal 3 and the outer wall of the inner cylinder 2, and the contact parts between the inner cylinder seal 4 and the inner wall of the outer cylinder are dynamic seals, and the contact parts between the outer cylinder seal 3 and the inner cylinder seal 4 and the blade grooves of the outer cylinder 1 or the inner cylinder 2 are static seals. Since the blades of the outer cylinder 1 or the inner cylinder 2 and the corresponding grooves are the conventional structures of the vane-type hydraulic rotary actuator, in order to better show the relationship between the outer cylinder seal 3, the inner cylinder seal 4 and the outer cylinder 1 or the inner cylinder 2, the following figure shows the contact parts between the outer cylinder seal 3 and the inner cylinder seal 4 and the outer cylinder 1 or the inner cylinder 2. Figures 1 to 4 In the figure, the blades of the outer cylinder 1 or the inner cylinder 2 and the corresponding grooves are not drawn.

[0031] The two working chambers formed by the outer cylinder 1 and the inner cylinder 2 of the vane-type hydraulic rotary actuator are closed chambers. When there is no internal sealing device at the blades of the outer cylinder 1 and the inner cylinder 2, the oil will seep out through the assembly gap between the internal parts. When the internal sealing device is set at the blades of the outer cylinder 1 and the inner cylinder 2, when the internal oil of the closed chamber flows to the internal sealing device through the gap between the blades of the outer cylinder 1 and the inner cylinder 2, due to the action of the outer cylinder seal 3 and the inner cylinder seal 4, the flowing oil is prevented from continuing to flow in the original direction under the action of the compressive stress of the outer cylinder seal 3 and the inner cylinder seal 4. When the oil pressure value in the working chamber increases, the cross-sectional shape of the outer cylinder seal 3 and the inner cylinder seal 4 changes under the extrusion of the pressure oil, so that the compressive stress of the outer cylinder seal 3 and the inner cylinder seal 4 increases, and the outer cylinder seal 3 and the inner cylinder seal 4 are more closely attached to the inner wall of the outer cylinder 1 or the outer wall of the inner cylinder 2, the contact stress value is larger, and the performance of the sealing oil is better.

[0032] Embodiment 2:

[0033] Based on the above embodiments, this embodiment further defines the structure of the outer cylinder seal 3 or the inner cylinder seal 4, such as Figure 3 As shown, the outer tube seal 3 and the inner tube seal 4 have the same structure and both include a rectangular sealing skeleton 5. A ring-shaped embedding groove is provided in the middle of the sealing skeleton 5, and an elastic member 6 is nested in the embedding groove. The elastic member 6 of the outer tube seal 3 abuts against the outer wall of the inner tube 2. A sealing ring 7 is also nested outside the elastic member 6 in the embedding groove in the middle of the sealing skeleton 5. The sealing ring 7 of the outer tube seal 3 abuts against the outer wall of the inner tube 2, and the sealing ring 7 of the inner tube seal 4 abuts against the inner wall of the outer tube 1.

[0034] When an internal sealing device is provided at the blades of the outer cylinder 1 and the inner cylinder 2, when the internal oil of the closed cavity flows to the internal sealing device through the gap between the blades of the outer cylinder 1 and the inner cylinder 2, the flowing oil is stopped from continuing to flow in the original direction due to the elastic force of the elastic member 6 under the action of the compressive stress of the sealing ring 3. When the oil pressure value in the working chamber increases, the cross-sectional shape of the elastic member 6 changes under the extrusion of the pressure oil, so that the compressive stress between the elastic member 6 and the sealing ring 7 increases, and the sealing ring 7 fits more closely with the inner wall of the outer cylinder 1 or the outer wall of the inner cylinder 2, the contact stress value is larger, and the performance of the sealing oil is better. The wear resistance of the elastic member 6 is relatively poor. In order to avoid direct contact between the elastic member 6 and the moving surface of the inner wall of the outer cylinder 1 or the outer wall of the inner cylinder 2 during the operation of the rotary actuator, the elastic member 6 is severely worn with the extension of the use time, and the sealing performance is reduced. A sealing ring 7 with excellent wear resistance is arranged between the elastic member 6 and the sealing surface of the inner wall of the outer tube 1 or the outer wall of the inner tube 2, so as to avoid direct contact between the elastic member 6 and the moving surface of the inner wall of the outer tube 1 or the outer wall of the inner tube 2, thereby improving the sealing performance and durability of the internal sealing device. Among them, the material selected for the elastic body 2 is rubber, and the material selected for the sealing ring 3 is plastic. The other parts of this embodiment are the same as those of the above embodiment and will not be described in detail.

[0035] Embodiment 3:

[0036] Based on the above embodiments, this embodiment further defines the structure and connection relationship between the outer cylinder seal 3 and the outer cylinder 1, such as Figure 4As shown, the outer tube seal 3 includes a sealing skeleton 5, a ring-shaped embedding groove is provided in the middle of the sealing skeleton 5, an elastic member 6 is nested in the embedding groove, and the side of the sealing skeleton 5 facing the inner tube 2 is a concave arc surface that fits the outer wall of the inner tube 2; a sealing ring 7 is also nested outside the elastic member 6 in the embedding groove in the middle of the sealing skeleton 5, and the sealing ring 7 of the outer tube seal 3 and the concave arc surface of the sealing skeleton 5 are in contact with the outer wall of the inner tube 2; an inwardly protruding boss is provided on the inner side of the outer tube 1, and a concave arc surface that fits the outer wall of the inner tube 2 is provided on the side of the boss facing the inner tube 2, and the sealing ring 7 of the outer tube seal 3, the concave arc surface of the sealing skeleton 5, and the concave arc surface of the boss inside the outer tube 1 are in contact with the outer wall of the inner tube 2. In order to make the outer wall of the inner tube 2 better contact with the sealing ring 7 of the outer tube seal 3, the sealing frame 5, and the inner boss of the outer tube 1, ensure the sealing effect, and improve the working efficiency of the vane type hydraulic rotary actuator, the structures of the sealing ring 7 of the outer tube seal 3, the sealing frame 5, and the inner boss of the outer tube 1 are particularly limited. The other parts of this embodiment are the same as the above embodiment and will not be repeated.

[0037] Embodiment 4:

[0038] Based on the above embodiments, this embodiment further defines the structure and connection relationship between the outer cylinder seal 3 and the outer cylinder 1, such as Figure 4 As shown, the inner tube seal 4 includes a sealing skeleton 5, a ring-shaped embedding groove is provided in the middle of the sealing skeleton 5, an elastic member 6 is nested in the embedding groove, and the side of the sealing skeleton 5 facing the outer tube 1 is a convex arc surface that fits the outer wall of the outer tube 1; a sealing ring 7 is also nested outside the elastic member 6 in the embedding groove in the middle of the sealing skeleton 5, and the sealing ring 7 of the inner tube seal 4 and the convex arc surface of the sealing skeleton 5 abut against the inner wall of the outer tube 1; an outwardly protruding boss is provided on the outer side of the inner tube 1, and a convex arc surface that fits the outer wall of the outer tube 1 is provided on the side of the boss facing the outer tube 1, and the sealing ring 7 of the inner tube seal 4, the convex arc surface of the sealing skeleton 5, and the convex arc surface of the boss on the outer side of the inner tube 1 abut against the inner wall of the outer tube 1. In order to make the sealing ring 7 of the inner wall cylinder seal 4 of the outer cylinder 1, the sealing frame 5, and the outer boss of the inner cylinder 1 better contact, ensure the sealing effect, and improve the working efficiency of the vane type hydraulic rotary actuator, the structures of the sealing ring 7 of the inner wall cylinder seal 4, the sealing frame 5, and the outer boss of the inner cylinder 1 are particularly limited. The other parts of this embodiment are the same as the above embodiment and will not be repeated.

[0039] Embodiment 5:

[0040] Based on the above embodiment, this embodiment further defines the positional relationship between the outer tube 1, the inner tube 2, the outer tube seal 3, and the inner tube seal 4, such as Figure 3 Figure 4As shown, the axes of the outer tube 1 and the inner tube 2 coincide with each other, the axis of the boss in the middle of the inner side of the outer tube 1 coincides with the axis of the outer tube 1, and the axis of the boss in the middle of the outer side of the inner tube 2 coincides with the axis of the inner tube 1; the groove of the boss in the middle of the inner side of the outer tube 1 coincides with the axis of the outer tube 1, and the groove of the boss in the middle of the outer side of the inner tube 2 coincides with the axis of the inner tube 1; the axes of the outer tube seal 3 and the inner tube seal 4 coincide with the axes of the grooves in which they are embedded. The other parts of this embodiment are the same as those of the above embodiment and will not be repeated.

[0041] It can be understood that the internal sealing device structure applied to the blade-type hydraulic rotary actuator according to an embodiment of the present invention, such as the working principle and working process of the elastic member 6 and the sealing ring and other components are all prior art and are well known to technicians in this field, and will not be described in detail here.

[0042] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. An internal sealing device for a vane-type hydraulic rotary actuator, characterized in that: The invention comprises an outer cylinder (1) and an inner cylinder (2), wherein the inner side of the outer cylinder (1) is provided with an inwardly protruding boss, and an outer cylinder seal (3) is embedded in the middle of the boss on the inner side of the outer cylinder (1), and the outer side of the inner cylinder (2) is provided with an outwardly protruding boss, and an inner cylinder seal (4) is embedded in the middle of the boss on the outer side of the inner cylinder (2). The inner cylinder (2) is embedded in the outer cylinder (1), and the outer wall of the inner cylinder (2) abuts against the outer cylinder seal (3) on the inner side of the outer cylinder (1), and the boss of the inner cylinder (2) and the inner wall of the outer cylinder (1) abut against the inner cylinder seal (4), so that the inner cylinder (2) divides the inner side of the outer cylinder (1) into two working chambers.

2. The internal sealing device for a vane-type hydraulic rotary actuator according to claim 1, characterized in that: The outer tube seal (3) and the inner tube seal (4) have the same structure, both comprising a rectangular sealing frame (5), a ring-shaped embedding groove is provided in the middle of the sealing frame (5), an elastic member (6) is nested in the embedding groove, the elastic member (6) of the outer tube seal (3) abuts against the outer wall of the inner tube (2), and the elastic member (6) of the inner tube seal (4) abuts against the inner wall of the outer tube (1).

3. The internal sealing device for a vane-type hydraulic rotary actuator according to claim 2, characterized in that: A sealing ring (7) is also embedded in the groove in the middle of the sealing frame (5) outside the elastic member (6); the sealing ring (7) of the outer tube sealing member (3) abuts against the outer wall of the inner tube (2); and the sealing ring (7) of the inner tube sealing member (4) abuts against the inner wall of the outer tube (1).

4. The internal sealing device for a vane-type hydraulic rotary actuator according to claim 1, characterized in that: The outer tube seal (3) comprises a sealing frame (5), a ring-shaped embedding groove is arranged in the middle of the sealing frame (5), an elastic member (6) is embedded in the embedding groove, and the side of the sealing frame (5) facing the inner tube (2) is a concave arc surface that fits the outer wall of the inner tube (2), and the elastic member (6) of the outer tube seal (3) and the concave arc surface of the sealing frame (5) are in contact with the outer wall of the inner tube (2).

5. The internal sealing device for a vane-type hydraulic rotary actuator according to claim 4, characterized in that: A sealing ring (7) is nested in the embedded groove in the middle of the sealing frame (5) outside the elastic member (6), and the sealing ring (7) of the outer cylinder sealing member (3) and the concave arc surface of the sealing frame (5) are in contact with the outer wall of the inner cylinder (2).

6. The internal sealing device for a vane-type hydraulic rotary actuator according to claim 5, characterized in that: An inwardly protruding boss is provided on the inner side of the outer cylinder (1); a concave arc surface that fits the outer wall of the inner cylinder (2) is provided on the side of the boss that faces the inner cylinder (2); the sealing ring (7) of the outer cylinder seal (3), the concave arc surface of the sealing frame (5), and the concave arc surface of the boss on the inner side of the outer cylinder (1) are in contact with the outer wall of the inner cylinder (2).

7. The internal sealing device for a vane-type hydraulic rotary actuator according to claim 1, characterized in that: The inner tube seal (4) comprises a sealing frame (5), a ring-shaped embedding groove is arranged in the middle of the sealing frame (5), an elastic member (6) is embedded in the embedding groove, and the side of the sealing frame (5) facing the outer tube (1) is a convex arc surface that fits the outer wall of the outer tube (1), and the elastic member (6) of the inner tube seal (4) and the convex arc surface of the sealing frame (5) are in contact with the inner wall of the outer tube (1).

8. The internal sealing device for a vane-type hydraulic rotary actuator according to claim 7, characterized in that: A sealing ring (7) is nested in the embedding groove in the middle of the sealing frame (5) outside the elastic member (6), and the sealing ring (7) of the inner cylinder sealing member (4) and the convex arc surface of the sealing frame (5) abut against the inner wall of the outer cylinder (1).

9. The internal sealing device for a vane-type hydraulic rotary actuator according to claim 8, characterized in that: The outer side of the inner tube (1) is provided with a boss protruding outward, and the side of the boss facing the outer tube (1) is provided with a convex arc surface that fits with the outer wall of the outer tube (1), and the sealing ring (7) of the inner tube seal (4), the convex arc surface of the sealing frame (5), and the convex arc surface of the boss on the outer side of the inner tube (1) are in contact with the inner wall of the outer tube (1).

10. An internal sealing device for a vane type hydraulic rotary actuator according to any one of claims 1 to 9, characterized in that: The axes of the outer cylinder (1) and the inner cylinder (2) coincide with each other; the axis of the boss in the middle of the inner side of the outer cylinder (1) coincides with the axis of the outer cylinder (1); the axis of the boss in the middle of the outer side of the inner cylinder (2) coincides with the axis of the inner cylinder (1); the groove of the boss in the middle of the inner side of the outer cylinder (1) coincides with the axis of the outer cylinder (1); the groove of the boss in the middle of the outer side of the inner cylinder (2) coincides with the axis of the inner cylinder (1); the axes of the outer cylinder seal (3) and the inner cylinder seal (4) coincide with the axes of the grooves in which they are embedded.

Images