Support and seal structure for an asymmetric actuator cylinder and asymmetric actuator cylinder

Abstract

This invention belongs to the field of hydraulic sealing, and relates to a support and sealing structure for an asymmetric actuated cylinder and the asymmetric actuated cylinder itself. The structure includes: a cylinder body, a piston, and a bushing; the cylinder body is a double-layered cylinder structure, with an annular cavity between the inner and outer cylinders serving as the piston cavity; the piston structure corresponds to the piston cavity and is cylindrical; the piston head extends into the annular cavity, and the piston slides and seals against the inner wall of the outer cylinder; the piston rod slides and seals against the outer wall of the inner cylinder at the piston cavity inlet via the bushing; the bushing is pressed into the annular gap between the piston cavity inlet on the outer wall of the inner cylinder and the piston rod; a return oil hole is formed on the bushing, and a first support ring groove is formed on the outer side of the return oil hole near the outlet of the annular cavity; a first sealing ring groove is formed on the outer side of the first support ring groove; the first support ring groove accommodates a first support ring, which is higher than the first support ring groove but does not obstruct the sliding seal of the piston; the first sealing ring groove accommodates a first sealing ring.

Description

Technical Field

[0001] This invention belongs to the field of hydraulic sealing, and relates to a support and sealing structure for an asymmetric actuator and an asymmetric actuator. Background Technology

[0002] The two piston rods of the asymmetric actuator experience significant force conflict during operation. This force conflict leads to substantial lateral loads on the piston rods during movement, thus exacerbating wear between the piston rods and the bushings. After a period of use, the piston rods will eventually wear out and fail, resulting in increased external leakage from the actuator and failure to meet sealing durability requirements. Therefore, it is necessary to improve the sealing structure of the actuator to achieve the required sealing durability.

[0003] Asymmetric actuators typically employ a support ring design to prevent premature failure due to wear between the piston rod and bushing. To ensure good lubrication, the support ring is usually positioned on the side adjacent to the hydraulic pressure in the actuator's control chamber, avoiding dry friction and premature wear that compromises durability. However, this support ring arrangement has minimal effect on reducing wear between the piston rod and bushing. Under lateral loads, the piston rod first contacts and wears against the bushing. Only after the bushing has worn to a certain extent does the support ring provide support and reduce wear, offering negligible improvement to actuator durability. Positioning it on the outer side exposes the support ring to dry friction, leading to premature wear and failure, thus limiting its effectiveness. Summary of the Invention

[0004] Purpose of the invention: In order to solve the problems of dry film and support function of the support ring, it is necessary to improve the design structure of support and sealing.

[0005] Technical solution:

[0006] In a first aspect, a support and sealing structure for an asymmetric actuator is provided, comprising: a cylinder, a piston, and a bushing;

[0007] The cylinder has a double-layer cylinder structure, with the annular cavity between the inner and outer cylinders serving as the piston cavity. The piston structure corresponds to the piston cavity and is a cylindrical structure.

[0008] The piston head extends into the annular cavity, the piston slides and seals against the inner wall of the outer cylinder, and the piston rod slides and seals against the outer wall of the inner cylinder at the piston cavity inlet through a bushing. The bushing is pressed into the annular gap between the piston cavity inlet and the piston rod on the outer wall of the inner cylinder.

[0009] An oil return hole is provided on the bushing, and a first support ring groove is provided on the outer side of the oil return hole near the outlet of the annular cavity. A first sealing ring groove is provided on the outer side of the first support ring groove.

[0010] The first support ring groove accommodates the first support ring, which is higher than the first support ring groove but does not obstruct the piston's sliding seal; the first sealing ring groove accommodates the first sealing ring; the first support ring allows the piston to directly contact the first support ring to form a friction pair, ensuring that the piston and bushing do not directly contact each other.

[0011] Furthermore, the structure also includes a second support ring;

[0012] A second support ring groove is formed inside the oil return hole; a second sealing ring groove is formed between the oil return hole and the second support ring groove.

[0013] The second support ring groove accommodates the second support ring, which is higher than the second support ring groove but does not obstruct the piston's sliding seal; the second sealing ring groove accommodates the second sealing ring.

[0014] Furthermore, a dust scraper ring groove is provided outside the first sealing ring groove to accommodate the dust scraper ring.

[0015] Furthermore, two annular grooves are made at the contact point between the piston head and the inner wall of the outer cylinder, one to accommodate the piston sealing ring and the other to accommodate the piston support ring.

[0016] Furthermore, the height of both the first and second support rings is 0.30-0.05mm higher than the groove of their own support rings.

[0017] Furthermore, the first and second support rings and the piston support ring are all made of high-strength non-metallic PEEK composite material.

[0018] Furthermore, the second support ring is in direct contact with the oil, while the first support ring is lubricated by the return oil.

[0019] Secondly, an asymmetric actuator is provided, comprising:

[0020] Support and sealing structure for asymmetric actuators.

[0021] The beneficial effects of this invention are:

[0022] By introducing return oil, rationally arranging the support rings, and selecting appropriate support ring materials, the durability of the actuator is further improved, thus enhancing the reliability of the product. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the sealing structure of an asymmetric actuator.

[0024] Among them, 1-cylinder, 2-piston head support ring, 3-piston head sealing ring, 4-second support ring, 5-first sealing ring, 6-oil return hole, 7-first support ring, 8-second sealing ring, 9-bulb, 10-dust scraper ring, 11-piston. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] The features and illustrative embodiments of various aspects of the present invention will now be described in detail. Numerous specific details are set forth in the following detailed description to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced without requiring some of these specific details. The following description of embodiments is merely intended to provide a better understanding of the invention by illustrating examples of the invention. The invention is by no means limited to any specific setups and methods set forth below, but covers any improvements, substitutions, and modifications to structures, methods, and devices without departing from the spirit of the invention. Well-known structures and techniques are not shown in the drawings and the following description to avoid unnecessarily obscuring the invention.

[0027] It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other, and the various embodiments can be referenced and cited in each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0028] This invention provides a support and sealing structure for an asymmetric actuator, such as... Figure 1 As shown, it includes: a cylinder, a piston, and a bushing;

[0029] The cylinder has a double-layer cylinder structure, with the annular cavity between the inner and outer cylinders serving as the piston cavity. The piston structure corresponds to the piston cavity and is a cylindrical structure.

[0030] The piston head extends into the annular cavity, the piston slides and seals against the inner wall of the outer cylinder, and the piston rod slides and seals against the outer wall of the inner cylinder at the piston cavity inlet through a bushing. The bushing is pressed into the annular gap between the piston cavity inlet and the piston rod on the outer wall of the inner cylinder.

[0031] An oil return hole is provided on the bushing, and a first support ring groove is provided on the outer side of the oil return hole near the outlet of the annular cavity. A first sealing ring groove is provided on the outer side of the first support ring groove.

[0032] The first support ring groove accommodates the first support ring, which is higher than the first support ring groove but does not obstruct the piston's sliding seal; the first sealing ring groove accommodates the first sealing ring; the first support ring allows the piston to directly contact the first support ring to form a friction pair, ensuring that the piston and bushing do not directly contact each other.

[0033] Furthermore, the structure also includes a second support ring;

[0034] A second support ring groove is formed inside the oil return hole; a second sealing ring groove is formed between the oil return hole and the second support ring groove.

[0035] The second support ring groove accommodates the second support ring, which is higher than the second support ring groove but does not obstruct the piston's sliding seal; the second sealing ring groove accommodates the second sealing ring.

[0036] Furthermore, a dust scraper ring groove is provided outside the first sealing ring groove to accommodate the dust scraper ring.

[0037] Furthermore, two annular grooves are made at the contact point between the piston head and the inner wall of the outer cylinder, one to accommodate the piston sealing ring and the other to accommodate the piston support ring.

[0038] Furthermore, the height of both the first and second support rings is 0.30-0.05mm higher than the groove of their own support rings.

[0039] Furthermore, the first and second support rings and the piston support ring are all made of high-strength non-metallic PEEK composite material.

[0040] Furthermore, the second support ring is in direct contact with the oil, while the first support ring is lubricated by the return oil.

[0041] In this invention, a piston head support ring 2 and a piston head sealing ring 3 are arranged between the cylinder 1 and the piston 11, with the piston head support ring located on one side of the rodless chamber of the actuating cylinder. A second support ring 4, a first sealing ring 5, a first support ring 7, a second sealing ring 8, and a dust scraper ring 10 are arranged between the bushing 9 and the piston 11. An oil return hole 6 is designed between the second sealing ring and the first support ring in the bushing 9. The first support ring is in direct contact with the oil, while the second support ring is lubricated by the oil return. The three support rings 2, 4, and 7 are made of high-strength non-metallic PEEK composite material. The support rings ensure that the piston and the support rings directly contact to form a friction pair, preventing direct contact between the piston and the bushing.

[0042] During the piston rod's movement, the support ring and piston wear against each other. Since the support ring is made of non-metallic material, the wear on the piston rod is relatively small, extending the piston rod's wear life and thus ensuring that the actuator cylinder has a high durability life.

[0043] The width of the support ring is selected based on the side load and the strength of the support ring material. The selection is based on the principle that the strength of the side load acting on the support ring must be less than the strength of the support ring material. If a support ring with higher strength is selected, the width of the support ring will be smaller under the same side load. Consequently, the length of the actuator cylinder will be reduced, resulting in a smaller volume and weight.

[0044] Return oil is introduced into the groove of the outer support ring on the bushing. Two support rings are arranged on the bushing.

[0045] The first support ring is arranged adjacent to the bushing and the control cavity.

[0046] A second support ring is arranged outside the first sealing ring of the bushing.

[0047] The support ring is made of high-strength PEEK composite material. Under the same working conditions, the support ring is shorter and the weight of the actuator cylinder structure increases less.

[0048] The piston head uses a support ring located on one side of the rodless chamber.

[0049] The present invention also provides an asymmetric actuator, comprising:

[0050] Support and sealing structure for asymmetric actuators.

[0051] The above-described embodiments are merely preferred embodiments of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be included within the scope of protection of the present invention.

Claims

1. A support and sealing structure for an asymmetric actuator, characterized in that, include: Cylinder, piston, and bushing; The cylinder has a double-layer cylinder structure, with the annular cavity between the inner and outer cylinders serving as the piston cavity. The piston structure corresponds to the piston cavity and is a cylindrical structure. The piston head extends into the annular cavity, the piston slides and seals against the inner wall of the outer cylinder, and the piston rod slides and seals against the outer wall of the inner cylinder at the piston cavity inlet through a bushing. The bushing is pressed into the annular gap between the piston cavity inlet and the piston rod on the outer wall of the inner cylinder. An oil return hole is provided on the bushing, and a first support ring groove is provided on the outer side of the oil return hole near the outlet of the annular cavity. A first sealing ring groove is provided on the outer side of the first support ring groove. The first support ring groove accommodates the first support ring, which is higher than the first support ring groove but does not obstruct the sliding seal of the piston; the first sealing ring groove accommodates the first sealing ring; the first support ring allows the piston to directly contact the first support ring to form a friction pair, ensuring that the piston and the bushing do not directly contact each other; The structure also includes a second support ring; A second support ring groove is formed inside the oil return hole; a second sealing ring groove is formed between the oil return hole and the second support ring groove. The second support ring groove accommodates the second support ring, which is higher than the second support ring groove but does not obstruct the piston's sliding seal; the second sealing ring groove accommodates the second sealing ring. A dust scraper ring groove is also provided outside the first sealing ring groove to accommodate the dust scraper ring. Two annular grooves are made at the contact point between the piston head and the inner wall of the outer cylinder, one to accommodate the piston sealing ring and the other to accommodate the piston support ring.

2. The structure according to claim 1, characterized in that, The height of both the first and second support rings is 0.30-0.05mm higher than the groove of their own support rings.

3. The structure according to claim 1, characterized in that, The first and second support rings, as well as the piston support ring, are all made of high-strength non-metallic PEEK composite material.

4. The structure according to claim 1, characterized in that, The second support ring is in direct contact with the oil, while the first support ring is lubricated by the return oil.

5. An asymmetric actuator, characterized in that, include: The support and sealing structure of the asymmetric actuator according to any one of claims 1-4.

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