Multi-point sealing test limiting tool for non-self-limiting hydraulic cylinder

Abstract

The utility model provides a multi-point sealing test limiting tool for a non-self-limiting hydraulic cylinder, and solves the technical problem that a piston rod cannot stay at a certain designated position after pressurization due to the fact that the hydraulic cylinder is not self-limited during a static sealing test of the non-self-limiting hydraulic cylinder. Comprising a base, and a mounting block, an adjusting block and a limiting block which are sequentially arranged on the base along the same straight line, a mounting through hole is formed in the mounting block and is used for being matched with a fastener to horizontally fix a shell of the non-self-limiting hydraulic cylinder; a threaded through hole is formed in the adjusting block, and a limiting assembly is installed on the threaded through hole. The limiting assembly comprises an adjusting bolt and a nut, and the piston rod of the non-self-limiting hydraulic cylinder is limited at different sites by adjusting the connecting position of the adjusting bolt and the threaded through hole; the limiting block is used for limiting movement of the shell of the non-self-limiting hydraulic cylinder and supporting the other end of the piston rod of the non-self-limiting hydraulic cylinder, and guiding is provided for movement of the piston rod.

Description

Technical Field

[0001] This utility model belongs to the field of aircraft hydraulic cylinder testing technology, specifically relating to a multi-point sealing test limiting tooling for hydraulic cylinders without self-limiting position. Background Technology

[0002] Hydraulic cylinders, as actuators in hydraulic systems, are widely used in aircraft hydraulic systems, commonly for landing gear retraction and extension, cabin door retraction and extension, speed brake retraction and extension, and flap retraction and extension. Most hydraulic cylinders have built-in limit functions, while a small number, due to special functions (such as when used with accessories), do not have self-limiting functions, such as... Figure 1 , Figure 2 As shown, the device includes a housing and a piston rod. The housing consists of a housing body and four symmetrically arranged support legs. A hydraulic chamber for mounting the piston rod is located within the housing body, and a sealing ring is installed within the hydraulic chamber. A pipe joint is also provided on the housing body, and mounting holes are provided on the support legs. A large disc is coaxially positioned at a distance from the bottom end of the piston rod (i.e., the end closest to the support leg), with a cylindrical section at the bottom end and the other end extending out of the hydraulic chamber. Because this type of hydraulic cylinder lacks self-limiting during operation, the static sealing performance of the cylinder can only be verified by using a limiting block after production or repair. This method is unreliable and only allows testing the sealing performance at a single point. After pressurization, the piston rod cannot remain at a specific position, affecting the test results and production progress.

[0003] Therefore, it is necessary to design a test limiting fixture that can limit the piston rod during the static sealing test of the hydraulic cylinder and allow the piston rod to remain at any position within the working stroke. Utility Model Content

[0004] The purpose of this invention is to solve the technical problem that, during the static sealing test of a hydraulic cylinder without self-limiting position, the piston rod cannot stay at a certain designated position after pressurization because the hydraulic cylinder itself has no self-limiting position. Therefore, this invention provides a limiting tooling for multi-point sealing test of a hydraulic cylinder without self-limiting position.

[0005] To achieve the above objectives, the technical solution provided by this utility model is as follows:

[0006] A multi-point sealing test limiting fixture for a hydraulic cylinder without self-limiting position is characterized by comprising a base, and a mounting block, an adjusting block, and a limiting block arranged sequentially on the base along the same straight line.

[0007] The mounting block is provided with mounting through holes for use with fasteners to horizontally fix the housing of the hydraulic cylinder without self-limiting position.

[0008] The adjusting block is provided with a threaded through hole, and a limit component is installed on the threaded through hole; the limit component includes an adjusting bolt and a nut, and the end of the adjusting bolt is provided with a blind hole adapted to the bottom end of the piston rod of the hydraulic cylinder without self-limiting; the adjusting bolt and the nut cooperate to limit the piston rod of the hydraulic cylinder without self-limiting at different positions by adjusting the connection position of the adjusting bolt and the threaded through hole;

[0009] The limiting block is used to restrict the movement of the housing of the hydraulic cylinder without self-limiting and to support the other end of the piston rod of the hydraulic cylinder without self-limiting, providing guidance for the movement of the piston rod; the limiting block is provided with an upward-opening groove, and the bottom of the groove is a semi-circular groove that matches the outer circumferential surface of the piston rod.

[0010] In use, the threaded through hole, the semi-circular groove and the piston rod of the hydraulic cylinder without self-limiting are coaxial (that is, the center of the threaded through hole, the center of the semi-circular groove and the axis of the piston rod of the hydraulic cylinder without self-limiting are on the same straight line), and the other end of the piston rod without self-limiting passes through the groove and is exposed.

[0011] The adjustment length of the adjusting bolt is greater than the working stroke of the piston rod of the hydraulic cylinder without self-limiting position.

[0012] Further, the direction of the straight line is defined as the X direction, the direction that is on the same horizontal plane and perpendicular to the X direction is the Y direction, and the direction that is perpendicular to the horizontal plane is the Z direction.

[0013] The mounting block is a cuboid with two mounting through holes along the Z direction.

[0014] The dimensions of the mounting block along the Y direction are adapted to the distance between the support legs of the hydraulic cylinder housing without self-limiting position;

[0015] The opening positions of the two mounting through holes correspond to the mounting hole positions on the support leg of the hydraulic cylinder housing without self-limiting. That is, the diameter of the two mounting through holes is not only consistent with the diameter of the mounting hole on the support leg of the hydraulic cylinder housing without self-limiting, but the center distance between the two mounting through holes is also consistent with the center distance between the mounting holes on the support leg of the hydraulic cylinder housing without self-limiting, which can ensure that the hydraulic cylinder housing is accurately and reliably connected to the mounting block.

[0016] The fastener is a pin.

[0017] Furthermore, the adjusting block is a cuboid, and its dimension along the Y direction is smaller than the distance between the legs of the housing of the hydraulic cylinder without self-limiting position; the threaded through hole includes a connecting section and a chamfered opening, and the connecting section of the threaded through hole is provided with an internal thread that matches the external thread of the adjusting bolt; the distance from the center of the threaded through hole to the bottom surface of the adjusting block is consistent with the distance from the central axis of the piston rod to the bottom surface of the housing when it is placed horizontally, ensuring accurate guidance.

[0018] Furthermore, the adjusting bolt includes a threaded connection section and a bolt head;

[0019] The threaded connection section includes a thread and a relief groove that are adapted to the threaded through hole of the adjusting block; the length of the thread is greater than the working stroke of the piston rod, ensuring that the piston rod can stay at any position within the working stroke.

[0020] The bolt head has a blind hole; the depth of the blind hole is greater than the length of the cylindrical section at the bottom of the piston rod, ensuring that the pressure is applied to the large circular end face at the bottom of the piston rod during the test. Its inner diameter is slightly larger than the outer diameter of the cylindrical section at the bottom of the piston rod (to provide good guidance) and smaller than the outer diameter of the large circular disc at the bottom of the piston rod; the nut is a hexagonal nut, used to tighten the adjusting bolt.

[0021] Furthermore, the limiting block is a cuboid, and its upper half has an upward-opening U-shaped groove along the Z direction; the semi-circular groove at the bottom of the U-shaped groove along the Y direction is slightly larger than the diameter of the exposed part of the piston rod.

[0022] Furthermore, the pin includes a cylindrical body and a cylindrical handle; the cylindrical body includes a cylindrical working section and a chamfer, the diameter of the cylindrical working section is consistent with the diameter of the mounting through hole of the mounting block and the diameter of the mounting hole of the hydraulic cylinder housing without self-limiting position; the diameter of the cylindrical handle is larger than that of the cylindrical body and the outer surface is knurled.

[0023] Furthermore, the base is rectangular, serving as the base of the entire tooling, with mounting blocks, adjusting blocks, and limiting blocks arranged sequentially along the length direction.

[0024] Furthermore, the mounting block, adjusting block, and limiting block are all connected to the base by welding to ensure a firm and reliable connection.

[0025] Furthermore, the base, mounting block, adjusting block, limiting block, pin, adjusting bolt, and nut are all made of 30CrMnSiA material.

[0026] Furthermore, the base, mounting block, adjusting block, limiting block, pin, adjusting bolt, and nut are all heat-treated, with a tensile strength of σ. b ≥900 ensures that it will not deform during long-term use.

[0027] In summary, the relative positions of the mounting blocks, adjusting blocks, and limiting blocks on the entire tooling should be compatible with the assembly dimensions of the hydraulic cylinder without self-limiting.

[0028] The advantages of this utility model are:

[0029] 1. The tooling designed in this utility model is simple to operate and easy to use. It can limit the piston rod of a hydraulic cylinder without self-limiting position, allowing the piston rod to stay at any position within the working stroke, so as to reliably carry out multi-point tests, ensure the static sealing performance of the hydraulic cylinder after repair, improve the production and maintenance progress, and also provide ideas and methods for testing similar products.

[0030] 2. This utility model can effectively solve the technical problem that, during static sealing tests of hydraulic cylinders without self-limiting mechanisms, the piston rod cannot remain at a specific position after pressurization because the hydraulic cylinder itself lacks self-limiting mechanisms. By changing the connection position between the adjusting bolt and the threaded through hole, the piston rod can be stopped at any designated position, facilitating static sealing tests. Attached Figure Description

[0031] Figure 1 Schematic diagram of an existing hydraulic cylinder without self-limiting position. Figure 1 ;

[0032] Figure 2 Schematic diagram of an existing hydraulic cylinder without self-limiting position. Figure 2 ;

[0033] Figure 3 This is a schematic diagram of the multi-point sealing test limiting tooling of this utility model;

[0034] Figure 4 This is a schematic diagram of the structure of the multi-point sealing test limiting tooling base of this utility model;

[0035] Figure 5 This is a schematic diagram of the structure of the multi-point sealing test limiting tooling mounting block of this utility model;

[0036] Figure 6 This is a schematic diagram of the structure of the adjusting block of the multi-point sealing test limiting tooling of this utility model;

[0037] Figure 7 This is a schematic diagram of the limiting block of the multi-point sealing test limiting tooling of this utility model;

[0038] Figure 8 This is a schematic diagram of the structure of the limiting tooling pin for the multi-point sealing test of this utility model;

[0039] Figure 9 This is a schematic diagram of the structure of the adjusting bolt of the multi-point sealing test limit tooling of this utility model;

[0040] Figure 10 This is a schematic diagram of the structure of the multi-point sealing test limiting tool nut of this utility model;

[0041] Figure 11 This is a diagram showing the usage status of the multi-point sealing test limiting tooling of this utility model;

[0042] Icon labels:

[0043] 1-Housing shell, 2-Piston rod, 3-Sealing ring, 4-Pipe fitting;

[0044] 5-Base, 6-Mounting block, 7-Adjusting block, 8-Limit block, 9-Pin, 10-Adjusting bolt, 11-Nut. Detailed Implementation

[0045] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0046] For convenience only, specific directional terms are used in the following description with reference to the corresponding drawings. This should not be considered a limitation of the present invention. When the defined directions in the drawings change, the directions indicated by these terms should be interpreted as the corresponding different directions.

[0047] A schematic diagram of a hydraulic cylinder without self-limiting position is shown below. Figure 1 and Figure 2 As shown, this utility model designs a multi-point sealing test limiting fixture for this type of hydraulic cylinder, the structure of which is as follows: Figures 3-10 As shown, it includes a base, and a mounting block, an adjusting block, and a limiting block that are sequentially mounted on the base along the same straight line. The relative positions of the three should be compatible with the assembly dimensions of the hydraulic cylinder without self-limiting. They can be connected to the base by welding to ensure reliable installation. The base is rectangular and serves as the base of the entire test limiting fixture, supporting the mounting block, adjusting block, and limiting block.

[0048] The direction of the straight line is defined as the X direction, the direction that is on the same horizontal plane and perpendicular to the X direction is the Y direction, and the direction that is perpendicular to the horizontal plane is the Z direction.

[0049] The mounting block is a cuboid used to mount and fix the housing of the self-limiting hydraulic cylinder. It has two mounting through holes along the Z-direction. The dimensions of the mounting block along the Y-direction are matched to the distance between the legs of the self-limiting hydraulic cylinder housing. The positions of the two mounting through holes correspond to the positions of the mounting holes on the legs of the self-limiting hydraulic cylinder housing. That is, the diameters of the two mounting through holes not only match the diameters of the mounting holes on the legs of the self-limiting hydraulic cylinder housing, but the center distance between the two mounting through holes also matches the center distance between the mounting holes on the legs of the self-limiting hydraulic cylinder housing. This ensures that the self-limiting hydraulic cylinder housing is accurately and reliably connected to the mounting block via pins. The pin consists of a cylindrical body and a cylindrical handle. The cylindrical body includes a cylindrical working section and a chamfer. The diameter of the cylindrical working section matches the diameter of both the mounting through holes in the mounting block and the mounting holes in the self-limiting hydraulic cylinder housing. The cylindrical handle has a larger diameter than the cylindrical body, and its outer surface is knurled.

[0050] The adjusting block is a cuboid, and its dimension along the Y direction is smaller than the distance between the legs of the hydraulic cylinder housing without self-limiting. The adjusting block has a threaded through hole, on which a limiting component is installed. The threaded through hole includes a connecting section and a chamfered opening. The limiting component includes an adjusting bolt and a nut. The connecting section of the threaded through hole has an internal thread that matches the external thread of the adjusting bolt. The adjusting bolt is used to adjust the test point of the hydraulic cylinder and includes a threaded connecting section and a bolt head. The threaded connecting section includes a thread that matches the threaded through hole of the adjusting block and a relief groove. The length of the thread is greater than the working stroke of the piston rod, ensuring that the piston rod can stop at any position within its working stroke. A blind hole is formed on the bolt head; the depth of the blind hole is greater than the length of the cylindrical section at the bottom of the piston rod, ensuring that the pressure acts on the large circular end face at the bottom of the piston rod during the test. Its inner diameter is slightly larger than the outer diameter of the cylindrical section at the bottom of the piston rod but smaller than the outer diameter of the large circular disc at the bottom of the piston rod. A hexagonal nut is used to tighten the adjusting bolt. The adjusting bolt and nut work together to limit the piston rod of the hydraulic cylinder without self-limiting position at different points by adjusting the connection position of the adjusting bolt and the threaded through hole. The distance from the center of the threaded through hole to the bottom surface of the adjusting block is the same as the distance from the piston rod to the bottom surface of the housing when it is placed horizontally.

[0051] The limiting block serves two purposes: firstly, it restricts the movement of the housing of the hydraulic cylinder without self-limiting, and secondly, it supports the other end of the piston rod of the hydraulic cylinder without self-limiting and provides guidance for the movement of the piston rod. The limiting block is a cuboid with an upward-opening U-shaped groove on its upper half along the Z direction. The bottom of the U-shaped groove is a semi-circular groove that matches the outer circumference of the piston rod, and the dimension of the semi-circular groove along the Y direction is slightly larger than the diameter of the exposed part of the piston rod.

[0052] In use, the other end of the piston rod of the hydraulic cylinder without self-limiting position extends out from the U-shaped groove; the threaded through hole and the semi-circular groove are coaxial with the piston rod of the hydraulic cylinder without self-limiting position.

[0053] To extend the overall service life of the tooling, the base, mounting block, adjusting block, limit block, pin, adjusting bolt, and nut are all made of 30CrMnSiA material. Furthermore, all components—base, mounting block, adjusting block, limit block, pin, adjusting bolt, and nut—have undergone heat treatment, achieving a tensile strength of σ. b ≥900, ensuring no deformation occurs during long-term use.

[0054] When using, such as Figure 11 As shown, the hydraulic cylinder is placed flat on the tooling of this utility model. After aligning the mounting through hole of the mounting block with the mounting hole of the hydraulic cylinder housing, the pin is inserted and fixed. The piston rod is placed at a certain position within the working stroke. The adjusting bolt is turned counterclockwise until the end face of the piston rod is in contact with its end face, and the nut is tightened. Then, the specified test pressure is applied to the pipe joint to conduct a static sealing test. Similarly, this method can be used to conduct static sealing performance tests on multiple points in sequence.

[0055] The above description is only a specific embodiment of this utility model, but the protection scope of this utility model 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 this utility model, and these modifications or substitutions should all be covered within the protection scope of this utility model.

Claims

1. A multi-point sealing test limiting tool for a self-limiting hydraulic cylinder, characterized in that: The base, the mounting block, the adjusting block and the limiting block are arranged in sequence along the same straight line; The mounting block is provided with a mounting through hole for cooperating with a fastener to horizontally fix the housing of the self-limiting hydraulic cylinder; The adjusting block is provided with a threaded through hole, and a limiting assembly is mounted on the threaded through hole; the limiting assembly comprises an adjusting bolt and a nut, and the end of the adjusting bolt is provided with a blind hole matched with the bottom end of the piston rod of the self-limiting hydraulic cylinder; the adjusting bolt and the nut are matched, and the connecting position of the adjusting bolt and the threaded through hole is adjusted to limit the piston rod of the self-limiting hydraulic cylinder at different positions; The limiting block is used for limiting the movement of the housing of the self-limiting hydraulic cylinder and supporting the other end of the piston rod of the self-limiting hydraulic cylinder to provide guidance for the movement of the piston rod; the limiting block is provided with a groove with an opening upward, and the groove bottom is a semicircular groove matched with the outer surface of the piston rod; In use, the threaded through hole, the semicircular groove and the piston rod of the self-limiting hydraulic cylinder are coaxial; The adjusting length of the adjusting bolt is greater than the working stroke of the piston rod of the self-limiting hydraulic cylinder.

2. The multi-point sealing test limiting tool for the self-limiting hydraulic cylinder according to claim 1, wherein: the straight line direction is defined as the X direction, the Y direction is perpendicular to the X direction and located in the same horizontal plane, and the Z direction is perpendicular to the horizontal plane; the mounting block is a cuboid, and two mounting through holes are formed in the mounting block along the Z direction; the size of the mounting block along the Y direction is matched with the distance between the legs of the housing of the self-limiting hydraulic cylinder; the opening positions of the two mounting through holes correspond to the mounting hole positions on the legs of the housing of the self-limiting hydraulic cylinder; the fastener is a pin.

3. The multi-point sealing test limiting tool for the self-limiting hydraulic cylinder according to claim 2, wherein: the adjusting block is a cuboid, and the size of the adjusting block along the Y direction is smaller than the distance between the legs of the housing of the self-limiting hydraulic cylinder; the threaded through hole comprises a connecting section and a hole opening chamfer.

4. The multi-point sealing test limiting tool for the self-limiting hydraulic cylinder according to claim 3, wherein: the adjusting bolt comprises a threaded connecting section and a bolt head; the threaded connecting section comprises threads matched with the threaded through hole and a tool withdrawal groove; the blind hole is formed in the bolt head; the depth of the blind hole is greater than the length of the bottom end cylindrical section of the piston rod, the inner diameter of the blind hole is greater than the outer diameter of the bottom end cylindrical section and smaller than the outer diameter of the large disc at the bottom end of the piston rod.

5. The multi-point sealing test limiting tool for the self-limiting hydraulic cylinder according to any one of claims 2-4, wherein: the limiting block is a cuboid, and a U-shaped groove is formed in the limiting block along the Z direction; the size of the semicircular groove at the groove bottom of the U-shaped groove along the Y direction is greater than the diameter of the exposed part of the piston rod.

6. The multi-point sealing test limiting tool for the self-limiting hydraulic cylinder according to claim 5, wherein: the pin comprises a cylindrical body and a cylindrical handle; the diameter of the cylindrical handle is greater than that of the cylindrical body, and the outer circular surface of the cylindrical handle is knurled.

7. The multi-point sealing test limiting tool for the self-limiting hydraulic cylinder according to claim 1, wherein: ​ The base is rectangular.

8. The multi-point sealing test limiting tool for the hydraulic cylinder without self-limiting position according to claim 1, characterized in that: The mounting block, the adjusting block and the limiting block are connected with the base by welding.

9. The multi-point sealing test limiting tool for the hydraulic cylinder without self-limiting position according to claim 2, characterized in that: The base, the mounting block, the adjusting block, the limiting block, the pin, the adjusting bolt and the nut are made of 30CrMnSiA material.

10. The multi-point sealing test limiting tool for the hydraulic cylinder without self-limiting position according to claim 9, characterized in that: The base, mounting block, adjusting block, limiting block, pin, adjusting bolt and nut are all heat treated, and the tensile strength σ b ≥900.

Images