Plunger hydraulic cylinder and oil passing structure thereof

Abstract

The utility model provides a plunger hydraulic cylinder and an oil passing structure thereof. The plunger hydraulic cylinder comprises a cylinder body, a piston, a piston rod and a valve seat assembly. The cylinder body is of a hollow structure; the piston and the piston rod are mounted in the cylinder body, and the piston is sleeved on the piston rod; the piston is provided with at least one oil passing channel capable of communicating the vertical faces of the two sides of the piston. The valve seat assembly is installed on the radial peripheral face of the cylinder body, a plurality of oil ports communicated with the cylinder body oil port are formed in the valve seat assembly, and the oil ports in the valve seat assembly are communicated. According to the novel oil passing structure of the plunger type cylinder, the plunger type cylinder extends out stably and is not clamped.

Description

Technical Field

[0001] The utility model relates to an oil passage structure for a plunger hydraulic cylinder, belonging to the technical field of hydraulic cylinders. Background Art

[0002] The structure of the plunger hydraulic cylinder is simple. The piston rod is driven to extend by the pressure difference between the large and small chambers, and is retracted by an external force. The plunger hydraulic cylinder ensures that the oil can always enter the cylinder by welding a oil pipe on the cylinder barrel. However, the existing oil passage method of the welded oil pipe occupies a large space and affects the installation of the main engine.

[0003] Therefore, the plunger hydraulic cylinder needs a new oil passage structure, which can ensure simple assembly, meet the installation of the main engine, and ensure the reliability of the product. Summary of the Invention

[0004] In view of the deficiencies of the prior art, the utility model provides an oil passage structure for a plunger hydraulic cylinder, which can make the plunger cylinder extend smoothly without jamming.

[0005] The utility model is realized according to the following technical solutions:

[0006] In a first aspect, the utility model provides an oil passage structure for a plunger hydraulic cylinder, including a cylinder block, a piston, a piston rod and a valve seat assembly; the cylinder block is a hollow structure; the piston and the piston rod are installed in the cylinder block, and the piston is sleeved on the piston rod; at least one oil passage is opened on the piston to communicate the two side vertical surfaces of the piston; the valve seat assembly is installed on the radial outer peripheral surface of the cylinder block, and a plurality of oil ports communicated with the oil ports of the cylinder block are arranged on the valve seat assembly, and the plurality of oil ports on the valve seat assembly are communicated with each other.

[0007] In some embodiments, a plurality of symmetrically arranged oil grooves are opened on the axial annular surfaces on both sides of the piston. The oil grooves are not communicated with the inner circumferential surface of the piston, and are communicated with the outer circumferential surface of the piston; all two oil grooves located on the axial annular surfaces on both sides and in the same position are communicated with each other through an axially extending oil hole, thereby forming the oil passage.

[0008] In some embodiments, a plurality of oil grooves are opened on each axial annular surface of the piston and are evenly arranged along the entire circumference.

[0009] In some embodiments, among the plurality of oil ports in the valve seat assembly, at least one oil port is a countersunk threaded hole and is blocked by a plug.

[0010] In some embodiments, there are three oil ports on the valve seat assembly that communicate with three oil ports on the cylinder block. Among them, the centers of the oil ports on both sides of the valve seat assembly are generally located on the horizontal center line of the top surface of the valve seat assembly, and the center of the oil port in the middle of the valve body assembly deviates from the horizontal center line and the vertical center line of the top surface of the valve seat assembly. The oil ports on both sides of the valve seat assembly are both set as counterbore threaded holes and are each blocked by a plug.

[0011] In some embodiments, a groove that encloses all the oil ports is formed on the side of the valve seat assembly that fits with the cylinder block, and all the oil ports are communicated through this groove.

[0012] In some embodiments, one side of the piston is axially limited in one direction by a stepped portion protruding outward on the piston rod, and the other side of the piston is axially limited in the other direction by a keyway structure.

[0013] In some embodiments, the keyway structure is realized in the following way:

[0014] A ring of keyways is provided on the piston rod. After the key abuts against the side of the piston, it is clamped in the keyway. The key cap is sleeved on the key, and then the key cap is fixed by a shaft retaining ring.

[0015] In some embodiments, the bottom surface of the valve seat assembly is set as an inner arc surface that can make it fit completely on the outer peripheral surface of the cylinder block, and the valve seat assembly is fixed on the cylinder block by welding; a plurality of blind threaded holes are provided on the top surface of the valve seat assembly for cooperating with fasteners to fix the valve seat assembly on the main machine.

[0016] In a second aspect, the present invention provides a plunger hydraulic cylinder, including the above-mentioned oil passage structure of the plunger hydraulic cylinder.

[0017] Advantages of the present invention:

[0018] The novel oil passage structure of the plunger cylinder provided by the present invention enables the plunger cylinder to extend smoothly without jamming; the key-fixed piston structure is simple in structure, easy to process and assemble, and improves the processing and assembly efficiency. Description of the Drawings

[0019] The drawings, as a part of the present invention, are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention, but do not constitute an improper limitation to the present invention. Obviously, the drawings described below are only some embodiments, and those of ordinary skill in the art can obtain other drawings based on these drawings without creative efforts.

[0020] In the drawings:

[0021] Figure 1 Cross-sectional view of the oil passage structure of the plunger hydraulic cylinder of the present utility model;

[0022] Figure 2 Top view of the oil passage structure of the plunger hydraulic cylinder of the present utility model;

[0023] Figure 3 Schematic diagram of the piston of the present utility model (a is the side view, b is the cross-sectional view);

[0024] Figure 4 Schematic diagram of the valve seat assembly of the present utility model (a is the partial cross-sectional view, b is the side view, c is the top view, d is the bottom view).

[0025] Reference signs in the drawings: retaining ring 1, key cap 2, key 3, piston 4, plug 5, valve seat assembly 6, cylinder block 7, piston rod 8, oil passage groove 9, oil passage hole 10, oil port 11, groove 12, threaded blind hole 13.

[0026] It should be noted that these drawings and textual descriptions are not intended to limit the scope of the concept of the present utility model in any way, but to illustrate the concept of the present utility model to those skilled in the art by referring to specific embodiments. Detailed implementation manners

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present utility model with reference to the accompanying drawings in the embodiments of the present utility model. The following embodiments are used to illustrate the present utility model, but are not used to limit the scope of the present utility model.

[0028] In the description of the present utility model, it should be noted that the orientation or positional relationships indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present utility model 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 should not be construed as a limitation of the present utility model.

[0029] In the description of the present utility model, 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 directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0030] Such as Figure 1 、 Figure 2As shown in the figure, a fuel passage structure of a plunger hydraulic cylinder includes a cylinder block 7, a piston 4, a piston rod 8, and a valve seat assembly 6; the cylinder block 7 is a hollow structure; the piston 4 and the piston rod 8 are installed in the cylinder block 7, and the piston 4 is sleeved on the piston rod 8; at least one fuel passage is provided on the piston 4 to communicate the two vertical surfaces on both sides of the piston; the valve seat assembly 6 is installed on the radial outer peripheral surface of the cylinder block 7, and a plurality of oil ports 11 communicating with the cylinder block oil ports are provided on the valve seat assembly 6, and the plurality of oil ports 11 on the valve seat assembly 6 communicate with each other.

[0031] The above piston structure will be further described below.

[0032] As Figure 3 shown in the figure, a plurality of symmetrically arranged fuel grooves 9 are provided on the axial annular surfaces on both sides of the piston 4. The fuel grooves 9 do not communicate with the inner circumferential surface of the piston 4 and communicate with the outer circumferential surface of the piston 4; all two fuel grooves 9 located on the axial annular surfaces on both sides and in the same position are communicated with each other through an axially extending fuel hole 10, thereby forming a fuel passage.

[0033] For a further solution, continue to refer to Figure 3 shown in the figure, a plurality of fuel grooves 9 are evenly arranged along the entire circumference on each axial annular surface of the piston 4.

[0034] In a preferred solution, in this embodiment, four fuel grooves 9 are provided on each axial annular surface of the piston 4, and the four fuel grooves 9 on the axial annular surfaces on both sides are communicated through four axially extending fuel holes 10. Of course, in actual design, it is not limited to the above four fuel grooves, and three fuel grooves or five fuel grooves can also be provided.

[0035] The above valve seat assembly structure will be further described below.

[0036] As Figure 4 shown in the figure, among the plurality of oil ports 11 in the valve seat assembly 6, at least one oil port 11 is a countersunk threaded hole and is blocked by a plug 5.

[0037] For a further solution, continue to refer to Figure 1 、 Figure 2 、 Figure 4 shown in the figure, the valve seat assembly 6 is provided with three oil ports 11 communicating with three oil ports on the cylinder block; among them, the centers of the oil ports 11 on both sides of the valve seat assembly 6 are generally located on the horizontal center line of the top surface of the valve seat assembly 6, and the center of the oil port 11 in the middle of the valve body assembly 6 deviates from the horizontal center line and the vertical center line of the top surface of the valve seat assembly 6; the oil ports 11 on both sides of the valve seat assembly 6 are both countersunk threaded holes and are each blocked by a plug 5.

[0038] For a further solution, continue to refer to Figure 4As shown, on the side of the valve seat assembly 6 that fits against the cylinder block 7, there is a groove 12 that encloses all the oil ports 11, and all the oil ports 11 are connected through this groove 12.

[0039] For a further solution, continue to refer to Figure 4 As shown, the bottom surface of the valve seat assembly 6 is set as an inner arc surface that can make it fit completely on the outer peripheral surface of the cylinder block 7 in the radial direction, and the valve seat assembly 6 is fixed on the cylinder block 7 by welding; there are a plurality of blind threaded holes 13 on the top surface of the valve seat assembly 6, which are used to cooperate with fasteners to fix the valve seat assembly 6 on the main machine.

[0040] The following further explains the structure for limiting the above-mentioned piston.

[0041] Continue to refer to Figure 1 As shown, one side of the piston 4 is axially limited in one direction by the stepped portion protruding outward on the piston rod 8, and the other side of the piston 4 is axially limited in the other direction by a keyway structure.

[0042] For a further solution, continue to refer to Figure 1 As shown, the keyway structure is realized in the following way: there is a circumferential keyway on the piston rod 8, the key 3 abuts against the side surface of the piston 4 and is clamped in the keyway, the key cap 2 is sleeved on the key 3, and then the key cap 2 is fixed by a shaft retaining ring 1.

[0043] In summary, the present invention provides a new oil passage structure for a plunger cylinder. By providing an oil passage groove and oil passage holes on the piston, the three oil ports on the valve seat assembly communicate with the three oil ports on the cylinder block, and the three oil ports on the valve seat assembly also communicate with each other. This oil passage structure ensures smooth oil flow when the plunger cylinder extends, making the plunger cylinder extend smoothly without jamming; in addition, the structure of using a key to fix the piston is simple in assembly and reliable in structure.

[0044] The following describes the plunger hydraulic cylinder provided by the present invention. The plunger hydraulic cylinder described below can be mutually corresponding and referred to with the oil passage structure of the plunger hydraulic cylinder described above.

[0045] A plunger hydraulic cylinder provided by the present invention may include the oil passage structure of the plunger hydraulic cylinder described in any one of the above embodiments.

[0046] The beneficial effects achieved by the plunger hydraulic cylinder provided by the present invention are consistent with those achieved by the oil passage structure of the plunger hydraulic cylinder provided by the present invention, so they will not be elaborated here.

[0047] In the specification provided herein, a large number of specific details are set forth. However, it will be understood that embodiments of the present invention may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0048] In addition, those skilled in the art will understand that although some of the embodiments described herein include certain features contained in other embodiments but not others, the combinations of the features of different embodiments are equally meant to be within the scope of protection of the present invention and form different embodiments. For example, in the above embodiments, those skilled in the art can use them in combination according to the known technical solutions and the technical problems to be solved by this application.

[0049] The above are only the preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. Although the present invention has been disclosed above with the preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art of this patent, without departing from the scope of the technical solution of the present invention, can make some changes or modifications using the technical content prompted above into equivalent embodiments of equivalent changes. However, as long as the content does not depart from the technical solution of the present invention, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A fuel passage structure of a plunger hydraulic cylinder, characterized in that, Comprising: A cylinder block, which is a hollow structure; A piston and a piston rod, which are installed in the cylinder block, and the piston is sleeved on the piston rod; at least one oil passage is opened on the piston to communicate the two vertical surfaces on both sides of the piston; A valve seat assembly, which is installed on the outer peripheral surface of the radial direction of the cylinder block, and a plurality of oil ports communicating with the oil ports of the cylinder block are provided on the valve seat assembly, and the plurality of oil ports on the valve seat assembly communicate with each other.

2. The oil passage structure of a plunger hydraulic cylinder according to claim 1, wherein: A plurality of symmetrically arranged oil grooves are opened on the axial annular surfaces on both sides of the piston, the oil grooves do not communicate with the inner circumferential surface of the piston, and the oil grooves communicate with the outer circumferential surface of the piston; All two oil grooves located on the axial annular surfaces on both sides and in the same position are communicated with each other through an axially extending oil hole, thereby forming the oil passage.

3. The oil passage structure of a plunger hydraulic cylinder according to claim 2, wherein: A plurality of oil grooves are opened on each axial annular surface of the piston and are evenly arranged along the entire circumference at intervals.

4. The oil passage structure of a plunger hydraulic cylinder according to claim 1, wherein: Among the plurality of oil ports in the valve seat assembly, at least one oil port is a countersunk threaded hole and is blocked by a plug.

5. The oil passage structure of a plunger hydraulic cylinder according to claim 4, wherein: The valve seat assembly is provided with three oil ports communicating with three oil ports on the cylinder block; wherein, the centers of the oil ports located on both sides of the valve seat assembly are generally located on the horizontal center line of the top surface of the valve seat assembly, and the center of the oil port located in the middle of the valve body assembly deviates from the horizontal center line and the vertical center line of the top surface of the valve seat assembly; The oil ports located on both sides of the valve seat assembly are both countersunk threaded holes and are each blocked by a plug.

6. The oil passage structure of a plunger hydraulic cylinder according to claim 1, wherein: A groove wrapping all the oil ports is opened on the surface of the valve seat assembly that fits the cylinder block, and all the oil ports are communicated through this groove.

7. The oil passage structure of a plunger hydraulic cylinder according to claim 1, wherein: One side surface of the piston is axially limited in one direction by a step protruding on the piston rod, and the other side surface of the piston is axially limited in the other direction by a keyway structure.

8. A hydraulic cylinder plunger oil passage structure according to claim 7, characterized in that, The keyway structure is realized in the following way: A circle of keyway grooves is provided on the piston rod, the key abuts against the side surface of the piston and is clamped in the keyway grooves, the key cap is sleeved on the key, and then the key cap is fixed by a shaft retaining ring.

9. The oil passage structure of a plunger hydraulic cylinder according to claim 1, wherein: The bottom surface of the valve seat assembly is an inner arc surface that can make it completely fit on the outer peripheral surface of the radial direction of the cylinder block, and the valve seat assembly is fixed on the cylinder block by welding; The top surface of the valve seat assembly is provided with a plurality of blind threaded holes for cooperating with fasteners to fix the valve seat assembly on the main machine.

10. A plunger hydraulic cylinder, wherein: It includes the oil passage structure of a plunger hydraulic cylinder according to any one of claims 1 to 9.

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