Durability test bed for sealing ring of hydraulic cylinder

Abstract

The utility model discloses a hydraulic cylinder sealing ring endurance test bench, which comprises a servo motor, an eccentric wheel, a connecting rod and a sealing ring test tool which are connected in sequence, a piston rod of a hydraulic cylinder is connected with the connecting rod, the piston rod and the connecting rod are arranged along the horizontal direction, and a support device is arranged on the piston rod between the sealing ring test tool and the connecting rod. The supporting device can balance radial force of the piston rod, so that the piston rod is only subjected to axial resultant force. The novel test bed is designed, the vertically arranged connecting rod is changed into the horizontally arranged connecting rod, the connecting rod is directly connected with the piston rod, the problem that a guide rail pair is easy to damage is solved, the radial force of the piston rod is balanced through the supporting device, the piston rod is only subjected to axial resultant force, a sealing ring is prevented from being subjected to lateral force, and the service life of the sealing ring is prolonged. The test data of the oil cylinder sealing ring is closer to the real working condition, and the service life of the sealing ring can be effectively estimated.

Description

Technical Field

[0001] The utility model relates to the technical field of experimental equipment for sealing rings, in particular to a durability test bench for sealing rings of hydraulic cylinders. Background Art

[0002] The durability of the hydraulic cylinder seal ring directly affects the reliability of engineering machinery. The seal ring test structure in the prior art is shown in the figure. The drive unit is connected to the horizontally moving slider, the piston rod of the hydraulic cylinder is connected, and the connecting rod connected to the drive unit is located at the bottom of the slider. The eccentric wheel in the drive unit is used to drive the connecting rod and the slider to move, so as to transmit the force to the piston rod, and the oil cylinders on both sides are tested for sealing. Since the connecting rod has both horizontal and vertical components on the slider, it is easy to cause damage to the guide rail that slides with the slider, and will cause the tested oil cylinder seal ring to be subjected to a large lateral force, aggravating the seal ring loss, causing deviation in the experimental results, and the seal ring life cannot be accurately evaluated through the test.

[0003] Therefore, it is necessary to design an experimental bench that can prevent the sealing ring from being subjected to lateral force and improve the accuracy of the experiment. Utility Model Content

[0004] In order to solve the technical problem in the prior art that the guide rail and the sealing ring are worn due to the additional lateral force during the hydraulic cylinder sealing ring test, resulting in the inability to accurately evaluate the life of the sealing ring, the utility model provides a hydraulic cylinder sealing ring durability test bench to solve the above problem.

[0005] The technical solution adopted by the utility model to solve its technical problems is: a hydraulic cylinder sealing ring durability test bench, including a servo motor, an eccentric wheel, a connecting rod and a sealing ring testing fixture connected in sequence, the piston rod of the hydraulic cylinder is connected to the connecting rod, the piston rod and the connecting rod are arranged in a horizontal direction, and a supporting device is also provided on the piston rod located between the sealing ring testing fixture and the connecting rod, and the supporting device can balance the radial force of the piston rod so that the piston rod is only subjected to an axial resultant force.

[0006] Furthermore, the supporting device includes a supporting frame and a bearing or a guide sleeve mounted on the supporting frame.

[0007] Furthermore, the support device includes a support frame and a hydrostatic support plate installed on the support frame. The hydrostatic support plate is connected to the hydraulic system and achieves the balance of the force acting on the piston rod in the circumferential direction through the flow of hydraulic oil.

[0008] Furthermore, the hydrostatic support plate comprises a disc sleeved on a piston rod, and three or more oil grooves are arranged in a circular array on the inner circumference of the disc, each of the oil grooves is connected to the outer circumference of the disc through a main oil channel, and the oil pipeline of the hydraulic system is connected to the main oil channel, and each main oil channel is connected to each other.

[0009] Furthermore, at least two of the main oil passages are connected to the first oil passage extending to the end face of the disc, each first oil passage is connected to the second oil passage extending from the outer circumference of the disc to the interior of the disc, and at least every two second oil passages are connected to each other, thereby reducing the number of main oil passages connected to the oil pipeline.

[0010] Furthermore, the ratio of the axial thickness of the oil groove to the axial thickness of the disc is 1 / 4 to 1 / 3.

[0011] Furthermore, the oil groove is composed of two or more arc-shaped grooves arranged axially at intervals, and adjacent arc-shaped grooves are connected through notches.

[0012] Furthermore, there are three corresponding oil tanks and main oil passages, two of which are connected through the corresponding first oil passage and second oil passage, and one of the two main oil passages and the third main oil passage are connected to the oil pipeline.

[0013] Furthermore, one end of the second oil passage extending to the outer peripheral surface of the disc has a countersunk hole structure that cooperates with the plug.

[0014] Furthermore, the servo motor, the sealing ring testing fixture and the supporting device are all placed on a horizontal platform.

[0015] The beneficial effects of the utility model are:

[0016] (1) The utility model designs a new test bench, changes the vertically arranged connecting rod to a horizontal one, and directly connects the connecting rod to the piston rod, thereby solving the problem of easy damage when using a guide pair. At the same time, the radial force of the piston rod is balanced by a supporting device, so that the piston rod is only subjected to an axial force, thereby preventing the sealing ring from being subjected to lateral force. This makes the test data of the cylinder sealing ring closer to the actual working conditions, which is convenient for effectively estimating the service life of the sealing ring.

[0017] (2) The test bench described in the utility model has low cost and is easy to promote.

[0018] (3) The utility model adopts a static pressure support plate connected to the hydraulic system, and utilizes the free distribution of hydraulic oil in each oil tank to balance the lateral force. It has a simple structure and is easy to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0020] Figure 1 It is a schematic diagram of a durability test structure of a hydraulic cylinder seal ring in the prior art;

[0021] Figure 2 This is a front view of a specific implementation of the hydraulic cylinder seal ring durability test bench described in the utility model

[0022] Figure 3 This is a front view of the static pressure support plate in the utility model;

[0023] Figure 4 It is a left view of the static pressure support plate in the utility model;

[0024] Figure 5 yes Figure 3 AA section view;

[0025] Figure 6 yes Figure 4 BB section view;

[0026] Figure 7 yes Figure 4 CC section view;

[0027] Figure 8 yes Figure 4 DD section view.

[0028] In the figure, 1. drive unit, 2. slider, 3. piston rod, 4. connecting rod, 5. servo motor, 6. eccentric wheel, 7. sealing ring test fixture, 8. horizontal platform, 9. supporting device, 901. supporting frame, 902. static pressure supporting plate, 9021. disc, 9022. oil tank, 9023. main oil channel, 9024. first oil channel, 9025. second oil channel, 10. hydraulic system, 11. countersunk structure, 12. arc groove, 13. notch. DETAILED DESCRIPTION

[0029] The embodiments of the present invention are described in detail below, and examples of the embodiments 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.

[0030] like Figure 2 As shown, a hydraulic cylinder sealing ring durability test bench comprises a servo motor 5, an eccentric wheel 6, a connecting rod 4 and a sealing ring test fixture 7. The eccentric wheel 6 is connected to the motor shaft of the servo motor 5, one end of the connecting rod 4 is connected to the eccentric shaft, and the other end is hinged to the piston rod 3 of the hydraulic cylinder. The sealing ring test fixture 7 has a testing function. The sealing ring of the hydraulic cylinder to be tested is installed in the sealing ring test fixture 7. A supporting device 9 is also provided on the piston rod 3 located between the sealing ring test fixture 7 and the connecting rod 4. The servo motor 5, the sealing ring test fixture 7 and the supporting device 9 are all placed on a horizontal platform 8 or a factory floor. The piston rod 3 and the connecting rod 4 are arranged in a horizontal direction. The supporting device 9 can balance the radial force of the piston rod 3 so that the piston rod 3 is only subjected to an axial resultant force.

[0031] The connecting rod 4 in the utility model applies the force of the piston rod 3 to the end of the piston rod 3. Compared with the prior art in which the force of the connecting rod 4 is applied to the slider (i.e., the outer peripheral surface of the piston rod 3), there is no need for the cooperation of the slider and the guide rail, thereby avoiding the risk of damage to the linear guide rail. In addition, the force of the connecting rod 4 on the piston rod 3 mainly acts in the axial direction, and the influence of the lateral force (i.e., the force in the radial direction) is reduced. At the same time, due to the use of a supporting device 9 that can balance the radial force, the piston rod 3 can be subjected to balanced force in the circumferential direction without radial deviation. The piston rod 3 only transmits the axial force in the direction of the sealing ring of the hydraulic cylinder 7, thereby avoiding the reduction of detection accuracy of the sealing ring due to the lateral force.

[0032] Since there is no bearing or guide structure between the sealing ring and the piston rod 3 in the hydraulic cylinder, the hydraulic cylinder cannot balance the lateral force through its own structure. The support device 9 can balance the lateral force at the middle of the piston rod 3 (outside the cylinder body of the hydraulic cylinder 7). The support device 9 can include a support frame 901 and a bearing or a guide sleeve mounted on the support frame 901. The bearing or the guide sleeve is used to limit the circumferential position of the piston rod 3 so that the piston rod 3 has only axial movement, thereby completing the balance of the lateral force outside the hydraulic cylinder, and there is no need to solve the lateral force problem at the sealing ring.

[0033] In a preferred embodiment of the utility model, the support device 9 includes a support frame 901 and a hydrostatic support plate 902 installed on the support frame 901. The hydrostatic support plate 902 is connected to the hydraulic system 10, and realizes the balance of the circumferential force of the piston rod 3 through the flow of hydraulic oil. The hydrostatic support plate 902 has multiple oil channels inside. The hydrostatic support means that the hydraulic pressure input into the hydrostatic support plate 902 is constant. Through the free flow of hydraulic oil between the oil channels, the direction of the hydraulic pressure is adjusted according to the lateral force of the connecting rod 4 on the piston rod 3, so that the piston rod 3 is subjected to a balanced circumferential force.

[0034] The working principle is: the servo motor 5 drives the eccentric wheel 6 to rotate and drive the connecting rod 4, and the connecting rod 4 drives the piston rod 3 to move horizontally. The horizontal movement of the piston rod 3 causes loss to the sealing ring installed in the sealing ring test fixture 7. When working, the sealing ring test fixture is also connected to a separate hydraulic system to apply hydraulic pressure to the sealing ring. The static pressure support plate 902 is connected to the hydraulic system 10 to balance the lateral force.

[0035] The static pressure support plate 902 may, but is not limited to, adopt the following structure:

[0036] like Figure 7As shown, the hydrostatic support disc 902 includes a disc 9021 sleeved on the piston rod 3, and three or more oil grooves 9022 are arranged in a circular array on the inner circumference of the disc 9021. Each oil groove 9022 is connected to the outer circumference of the disc 9021 through a main oil channel 9023. The oil pipeline of the hydraulic system 10 is connected to the main oil channel 9023, and each main oil channel 9023 is connected to each other. The disc 9021 fits the outer circumferential surface of the piston rod 3, and the piston rod 3 blocks the inner surface of the oil groove 9022 to form a cavity for accommodating hydraulic oil. Before the test, the hydraulic system 10 first inputs hydraulic oil into the disc 9021, and the hydraulic oil is evenly distributed to each oil groove 9022. The hydraulic oil in the oil groove 9022 is in direct contact with the piston rod 3. When the connecting rod 4 exerts a radial component on the piston rod 3, at the moment of force, the hydraulic oil in the oil groove 9022 along the direction of the radial component will flow to other oil grooves 9022 through the interconnected main oil channels 9023 due to the pressure (the movement amplitude of this action is very small, so the piston rod 3 is always in contact with the circumferential surface of the disc 9021, and the hydraulic oil will not leave the oil groove 9022), so that the circumferential direction The hydraulic pressure is different, which is balanced with the radial component of the connecting rod 4 on the piston rod 3, so that the resultant force on the piston rod 3 is an axial force, thereby preventing the sealing ring from being subjected to lateral force.

[0037] The main oil passages 9023 can be interconnected by connecting each main oil passage 9023 to the same oil pipeline, but this will result in too many pipelines outside the disc 9021. Therefore, the utility model can connect part or all of the main oil passages 9023 inside the disc 9021 to simplify the structure outside the disc 9021. The specific structure is as follows:

[0038] like Figure 3-Figure 6 As shown, at least two main oil passages 9023 are connected to the first oil passage 9024 extending to the end surface of the disc 9021, and each first oil passage 9024 is connected to the second oil passage 9025 extending from the outer circumference of the disc 9021 to the inside of the disc 9021. At least every two second oil passages 9025 are connected to each other, so that the number of main oil passages 9023 connected to the oil pipeline is reduced. The first oil passage 9024 and the second oil passage 9025 extending to the end of the surface of the disc 9021 are blocked under normal conditions, and preferably a countersunk hole structure 11 cooperating with the plug is set at the end. The second oil passage 9025 and the main oil passage 9023 are located in different planes, such as Figure 5As shown, the second oil passage 9025 is close to one axial end of the disc 9021, and the main oil passage 9023 is close to the other axial end of the disc 9021. The second oil passage 9025 and the main oil passage 9023 are connected through the first oil passage 9024 extending axially, which can avoid too many hole structures in the same plane in the disc 9021, affecting the structural strength of the disc 9021. Among the main oil passages 9023 interconnected through the first oil passage 9024 and the second oil passage 9025, only one main oil passage 9023 needs to be connected to the oil pipeline, and the other main oil passages 9023 can be blocked with plugs, and the hydraulic oil flows between the interconnected main oil passages 9023 through the first oil passage 9024 and the second oil passage 9025. In addition, the first oil passage 9024 and the second oil passage 9025 extend to the surface of the disc 9021. Compared with the channel structure completely located inside the disc 9021, the processing technology is simpler and can be achieved by drilling after the disc 9021 is processed.

[0039] In a specific embodiment of the present utility model, Figure 6 and Figure 7 As shown, there are three oil grooves 9022 and three main oil passages 9023 correspondingly arranged, wherein two main oil passages 9023 are connected through the corresponding first oil passage 9024 and second oil passage 9025, and one of the two main oil passages 9023 and the third main oil passage 9023 are connected to the oil pipeline. Assuming that the three main oil passages 9023 are named as the first main oil passage 9023, the second main oil passage 9023 and the third main oil passage 9023 respectively, and the main oil passage 9023 connected with the first oil passage 9024 and the second oil passage 9025 is the first main oil passage 9023 and the second main oil passage 9023, then one of the first main oil passage 9023 and the second main oil passage 9023 is connected to the oil pipeline, and the third main oil passage 9023 is also connected to the oil pipeline.

[0040] Regarding the axial dimension setting of the oil groove 9022, in order to distribute the hydraulic pressure of the hydraulic oil on the piston rod 3 as much as possible in the axial direction and reduce the single-point pressure on the outer peripheral surface of the piston rod 3, the axial thickness of the oil groove 9022 cannot be too small. Preferably, the ratio of the axial thickness of the oil groove 9022 to the axial thickness of the disk 9021 is 1 / 4~1 / 3.

[0041] The oil groove 9022 is an arc groove 12. In a preferred embodiment, Figure 5 and Figure 8 As shown, the oil groove 9022 is composed of two or more arc grooves 12 arranged axially at intervals, and adjacent arc grooves 12 are connected through gaps 13. The main oil channel 9023 is connected to one of the arc grooves 12 to improve the effect of axially uniform distribution of radial force.

[0042] In the description of the present invention, it is necessary to understand that the terms "thickness", "vertical", "horizontal", "inside", "outside", "axial", "radial", 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, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0043] In addition, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood in specific circumstances. In addition, in the description of the present utility model, unless otherwise specified, the meaning of "plurality" is two or more.

[0044] In this specification, the schematic representation of the terms does not necessarily refer to the same embodiment. Moreover, the specific features, structures, materials or characteristics described can be combined in any suitable manner in one or more embodiments.

[0045] Based on the above ideal embodiments of the utility model, the relevant staff can make various changes and modifications without deviating from the technical concept of the utility model through the above description. The technical scope of the utility model is not limited to the content of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A hydraulic cylinder seal durability test bench, Features: The invention comprises a servo motor (5), an eccentric wheel (6), a connecting rod (4) and a sealing ring testing fixture (7) which are connected in sequence. The piston rod (3) of the hydraulic cylinder is connected to the connecting rod (4). The piston rod (3) and the connecting rod (4) are arranged in a horizontal direction. A supporting device (9) is also provided on the piston rod (3) between the sealing ring testing fixture (7) and the connecting rod (4). The supporting device (9) can balance the radial force of the piston rod (3) so that the piston rod (3) is only subjected to the axial resultant force.

2. The hydraulic cylinder seal ring durability test bench according to claim 1, Features: The support device (9) comprises a support frame (901) and a bearing or a guide sleeve mounted on the support frame (901).

3. The hydraulic cylinder seal ring durability test bench according to claim 1, Features: The support device (9) comprises a support frame (901) and a static pressure support plate (902) mounted on the support frame (901); the static pressure support plate (902) is connected to the hydraulic system (10) and achieves a balance of the force acting in the circumferential direction of the piston rod (3) through the flow of hydraulic oil.

4. The hydraulic cylinder seal ring durability test bench according to claim 3, Features: The static pressure support disc (902) comprises a disc (9021) sleeved on a piston rod (3); three or more oil grooves (9022) are arranged in a circular array on the inner circumference of the disc (9021); each of the oil grooves (9022) is connected to the outer circumference of the disc (9021) via a main oil channel (9023); the oil pipeline of the hydraulic system (10) is connected to the main oil channel (9023), and each main oil channel (9023) is connected to each other.

5. The hydraulic cylinder seal ring durability test bench according to claim 4, Features: At least two of the main oil passages (9023) are in communication with a first oil passage (9024) extending to the end surface of the disc (9021), each first oil passage (9024) is in communication with a second oil passage (9025) extending from the outer circumference of the disc (9021) toward the inside of the disc (9021), and at least every two second oil passages (9025) are in communication with each other, thereby reducing the number of main oil passages (9023) connected to the oil pipeline.

6. The hydraulic cylinder seal ring durability test bench according to claim 4, Features: The ratio of the axial thickness of the oil groove (9022) to the axial thickness of the disc (9021) is 1 / 4 to 1 / 3.

7. The hydraulic cylinder seal ring durability test bench according to claim 6, Features: The oil groove (9022) is composed of two or more arc-shaped grooves (12) arranged at intervals in the axial direction, and adjacent arc-shaped grooves (12) are connected via notches (13).

8. The hydraulic cylinder seal ring durability test bench according to claim 5, Features: The oil grooves (9022) and the main oil passages (9023) are provided in three corresponding ways, wherein two main oil passages (9023) are connected via the corresponding first oil passages (9024) and second oil passages (9025), and one of the two main oil passages (9023) and the third main oil passage (9023) are connected to the oil pipeline.

9. The hydraulic cylinder seal ring durability test bench according to claim 5, Features: One end of the second oil channel (9025) extending to the outer peripheral surface of the disc (9021) has a countersunk hole structure (11) that cooperates with the plug.

10. The hydraulic cylinder seal ring durability test bench according to any one of claims 1 to 9, Features: The servo motor (5), the sealing ring testing fixture (7) and the supporting device (9) are all placed on a horizontal platform (8).

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