Multi-rod plunger long-stroke hollow hydraulic cylinder

Abstract

The invention provides a multi-rod plunger long-stroke hollow hydraulic cylinder which comprises an annular cylinder body, the annular cylinder body comprises an oil inlet cavity, an oil port communicated with the oil inlet cavity is formed in the annular cylinder body, a plurality of sets of holes which are evenly formed in the annular direction at intervals are formed in the end of the annular cylinder body, and plunger rods are arranged in the multiple sets of holes in a sliding and penetrating mode along the axes of the holes. Outer guide assemblies are arranged on the annular cylinder body in a sliding mode along the axes of the plunger rods, the outer guide assemblies are fixedly connected with the ends, extending out of the annular cylinder body, of the multiple sets of plunger rods, inner guide assemblies are arranged in the multiple sets of holes, and the inner guide assemblies conduct inner guide on the plunger rods. When the hydraulic cylinder is used, stress is more uniform, unbalance loading resistance and lateral force resistance are higher, the hydraulic cylinder is particularly suitable for the working condition of a long-stroke hydraulic cylinder, and the service life of the hydraulic cylinder is greatly prolonged. And meanwhile, the hollow structure of the hydraulic cylinder facilitates penetration of a mandrel and is used for load lifting working conditions, and the application range of the hydraulic cylinder is expanded.

Description

Technical Field

[0001] The invention relates to the technical field of hydraulic cylinders, and in particular to a multi-rod plunger long-stroke hollow hydraulic cylinder. Background Art

[0002] The plunger hydraulic cylinder is a single-acting cylinder. The hydraulic power can only work in one direction. The return stroke of the plunger usually needs to rely on gravity or external force. Due to its simple structure, the plunger hydraulic cylinder is usually used to achieve the movement of equipment under unidirectional load conditions, such as the lifting of large metallurgical machinery equipment, the horizontal pushing of heavy equipment, and the pushing up of the barrel of military equipment.

[0003] For example, a Chinese invention patent with publication number CN104454756B provides a self-returning plunger hydraulic cylinder, including an annular cylinder body with a cylindrical structure and a plunger extending into the interior of the annular cylinder body; the plunger is a cylindrical structure, and one end of the plunger outside the annular cylinder body is closed; it also includes a piston rod, one end of which is fixedly connected to the annular cylinder body, and the other end extends to the interior of the plunger, forming a closed cavity inside the plunger, and vacuuming the closed cavity.

[0004] Another example is the Chinese invention patent with publication number CN212868088U, which provides a long-stroke plunger hydraulic cylinder, including a cylinder barrel and a plunger. A cylinder cover is provided at the end of the cylinder barrel to close the cylinder barrel, one end of the plunger is arranged in the cylinder barrel, and a plunger ring is provided at the end of the plunger arranged in the cylinder barrel; a guide rail is provided in the cylinder barrel, and a guide slider is provided on the end of the plunger arranged in the cylinder barrel, the plunger slides and moves in the cylinder barrel, and the guide slider cooperates with the guide rail.

[0005] By analyzing the above patents and combining them with the existing technology, it is found that most of the existing hydraulic cylinders are single-plunger structures, and most of the application scenarios of single-plunger hydraulic cylinders are non-vertical installations. When the mass of the plunger is large, the plunger rod is unevenly stressed, and the overall structure of the hydraulic cylinder is easily bent downward due to the deadweight of the plunger, resulting in unilateral wear of the seals and guides. Especially for the use of long-stroke hydraulic cylinders, there are often eccentric loads and lateral forces, which also cause unilateral wear of the seals and guides of the single-plunger hydraulic cylinder, causing the hydraulic cylinder seal to leak oil, greatly reducing the service life of the hydraulic cylinder. In addition, since the plunger hydraulic cylinder is single-chamber controlled, the piston rod can usually only be extended for jacking conditions. When used for load lifting conditions, it is usually implemented with an external auxiliary arm, and the structure is bulky. Summary of the invention

[0006] In view of the shortcomings of the prior art, the present invention proposes a multi-rod plunger long-stroke hollow hydraulic cylinder to solve the technical problem that the existing non-vertically mounted plunger hydraulic cylinder and long-stroke plunger hydraulic cylinder mentioned in the background art will cause unilateral wear of the seal and guide due to the presence of eccentric load and lateral force during use. At the same time, the hollow structure of the hydraulic cylinder is convenient for passing the core shaft and is used in load lifting conditions, which expands the scope of application of the hydraulic cylinder.

[0007] To achieve the above object, the present invention provides the following technical solution: a multi-rod plunger long-stroke hollow hydraulic cylinder, comprising:

[0008] An annular cylinder body, the annular cylinder body includes an oil inlet chamber, the annular cylinder body is provided with an oil port connected to the oil inlet chamber, and the end of the annular cylinder body is provided with a plurality of groups of holes evenly arranged in annular directions and connected to the oil inlet chamber;

[0009] The plunger rod is provided with the same number as the holes, and is respectively slidably arranged along its axis and penetrated into the plurality of holes;

[0010] An external guide assembly is fixedly connected to the ends of the multiple groups of plunger rods and guides the plunger rods externally along the outer cylinder wall of the annular cylinder body; and

[0011] The inner guide components are provided in multiple groups and are respectively arranged in the multiple groups of holes and connected with the multiple groups of plunger rods to guide the plunger rods internally.

[0012] In a preferred embodiment, the annular cylinder comprises:

[0013] A first cylinder head, wherein a second cylinder head is arranged in parallel with each other at an interval on one side of the first cylinder head;

[0014] An inner cylinder barrel, both ends of which are sealed and fixedly connected to the first cylinder head and the first cylinder head respectively; and

[0015] The outer cylinder barrel has two ends respectively connected to the first cylinder head and the first cylinder head in a sealed and fixed manner, and is sleeved on the inner cylinder barrel to form an annular cavity for the plunger rod to move.

[0016] In a preferred embodiment, the first cylinder head and the second cylinder head are annular, and the inner cylinder barrel is a hollow structure and is connected to the center holes of the first cylinder head and the second cylinder head to cooperate to form a core shaft hole.

[0017] In a preferred embodiment, the outer guide assembly includes an outer guide sleeve, which is cylindrical and slidably sleeved on the annular cylinder along its axis, and the ends of the plurality of groups of plunger rods are fixedly connected to the outer guide sleeve.

[0018] In a preferred embodiment, the inner guide assembly includes:

[0019] An inner guide sleeve is disposed in the oil inlet chamber and communicated with the hole, and the plunger rod is slidably disposed in the inner guide sleeve; and

[0020] A sealing member is arranged in the inner guide sleeve and contacts the outer wall of the plunger rod so as to seal the gap between the plunger rod and the inner guide sleeve.

[0021] In a preferred embodiment, a mounting flange is provided at the end of the annular cylinder.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. When the hydraulic cylinder is in use, the oil port is connected to the pressure oil of the external hydraulic system, and oil is supplied to the oil inlet chamber through the oil port, so as to drive multiple plunger rods to move synchronously under the action of the external guide component. The hydraulic cylinder decomposes the traditional single plunger rod into multiple ones, and seals and guides the multiple plunger rods respectively through the cooperation of multiple groups of internal guide components, so that the force of the hydraulic cylinder is more uniform when in use, and the plunger rod has no contact with the inside of the oil inlet chamber. Only fine processing of the plunger rod surface is required to ensure the sealing performance, which reduces the processing difficulty and has a longer sealing life. The overall movement of multiple groups of plunger rods is guided by the external guide component, and the ability to resist eccentric load and lateral force is stronger, so that when it is installed in a non-vertical manner, it is not easy for the plunger rod to bend downward due to its own weight, which effectively avoids the unilateral wear of the contact surface caused by uneven force when the plunger rod contacts the annular cylinder body, and greatly improves the service life of the hydraulic cylinder. Especially for the use conditions of long-stroke hydraulic cylinders, since the internal and external guiding methods increase the piston rod rigidity and the ability to resist offset load and lateral force, the stroke of the hydraulic cylinder can be made longer and the service life of the hydraulic cylinder is also improved.

[0024] 2. The annular cylinder body in the hydraulic cylinder forms an annular cavity structure through the first cylinder head, the second cylinder head, the inner cylinder barrel and the outer cylinder barrel, so that the hydraulic cylinder can pass the mandrel of the mechanical equipment through the mandrel hole when in use, and can be used for load lifting conditions. The mandrel hole can also be used to thread cables or other components. Compared with traditional external cables, the hydraulic cylinder can protect the cables when threading them, reduce the wear of the moving part of the cables when the hydraulic cylinder is in use, effectively increase the service life of the cables, and make the appearance of the mechanical equipment more beautiful and practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific implementation of the present invention, the following will briefly introduce the drawings required for use in the specific implementation. In all the drawings, each element or part is not necessarily drawn according to the actual scale.

[0026] Figure 1 A cross-sectional view of a multi-rod plunger long-stroke hollow hydraulic cylinder provided by the present invention;

[0027] Figure 2 It is a cross-sectional schematic diagram of a multi-rod plunger long-stroke hollow hydraulic cylinder of the present invention.

[0028] Reference numerals:

[0029] 1. First cylinder head; 2. Mounting flange; 3. Outer cylinder barrel; 4. Outer guide sleeve; 5. Plunger rod; 6. Core shaft hole; 7. Inner guide sleeve; 8. Oil port; 9. Second cylinder head; 10. Inner cylinder barrel. DETAILED DESCRIPTION

[0030] The present invention is further described in detail below in conjunction with the accompanying drawings. It is necessary to point out here that the following specific implementation methods are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Technicians in this field can make some non-essential improvements and adjustments to the present invention based on the above application content.

[0031] Example:

[0032] like Figure 1 , 2 As shown, the present invention provides a multi-rod plunger long-stroke hollow hydraulic cylinder, including an annular cylinder body, the annular cylinder body including an oil inlet chamber, an oil port 8 connected to the oil inlet chamber is opened on the annular cylinder body, and multiple groups of holes are arranged evenly in annular directions and connected to the oil inlet chamber are opened at the end of the annular cylinder body. The annular cylinder body includes a first cylinder head 1, a second cylinder head 9, an inner cylinder barrel 10 and an outer cylinder barrel 3. The first cylinder head 1 and the second cylinder head 9 are arranged in parallel with each other, and the two ends of the inner cylinder barrel 10 and the outer cylinder barrel 3 are respectively sealed and fixedly connected to the first cylinder head 1 and the first cylinder head 1, and the outer cylinder barrel 3 is sleeved on the inner cylinder barrel 10 and forms an annular cavity for the movement of the plunger rod 5. The first cylinder head 1 and the second cylinder head 9 are annular, and the inner cylinder barrel 10 is a hollow structure and is connected to the center holes of the first cylinder head 1 and the second cylinder head 9 to form a core shaft hole 6.

[0033] It is installed in the use area, and a mounting flange 2 is provided at the end of the annular cylinder body to facilitate the installation of the hydraulic cylinder. The cable or core shaft can be passed through the core shaft hole 6 formed by the first cylinder head 1 and the second cylinder head 9 and the inner cylinder barrel 10. The core shaft is used for load lifting conditions, and when the cable is passed through, the cable can be protected and the aesthetics of the equipment is improved.

[0034] like Figure 1 , 2As shown, in this embodiment, it also includes plunger rods 5 with the same number of groups as the holes. The multiple groups of plunger rods 5 are respectively slidably arranged along their axes and penetrated into the multiple groups of holes. An outer guide component is slidably arranged on the annular cylinder body along the axes of the plunger rods 5. The outer guide component is fixedly connected to one end of the multiple groups of plunger rods 5 extending out of the annular cylinder body. The outer guide component includes an outer guide sleeve 4. The outer guide sleeve 4 is cylindrical and is slidably arranged on the annular cylinder body along its axis. The ends of the multiple groups of plunger rods 5 are fixedly connected to the outer guide sleeve 4.

[0035] The outer guide sleeve 4 can slide on the annular cylinder body along its axis, thereby externally guiding and positioning the movement of multiple groups of plunger rods 5, improving the anti-bending performance of the hydraulic cylinder and improving the anti-eccentric load capacity and reliability of the hydraulic cylinder.

[0036] like Figure 1 As shown, in this embodiment, multiple groups of holes are provided with inner guide components connected to multiple groups of plunger rods 5, and the plunger rods 5 are guided by the inner guide components. The inner guide components include an inner guide sleeve 7 disposed in the oil inlet chamber and connected to the holes, and the plunger rod 5 is slidably inserted into the inner guide sleeve 7. A seal in contact with the outer wall of the plunger rod 5 is disposed in the inner guide sleeve 7, and the gap between the plunger rod 5 and the inner guide sleeve 7 is sealed by the seal.

[0037] By arranging multiple inner guide sleeves 7 and coordinating with the arrangement of the outer guide sleeve 4, the guide contact area of ​​the plunger rod 5 is increased, and the sealing life and the anti-bending performance of the plunger rod 5 are further improved, which is particularly suitable for long-stroke hydraulic cylinders, broadens the application range of the hydraulic cylinder, and reduces the use cost. At the same time, the plunger rod 5 has no contact with the annular cylinder body, and there is no matching requirement between the two. Therefore, only the surface of the plunger rod 5 needs to be finely processed to ensure the sealing performance, which reduces the processing difficulty, and the material cost and processing cost are lower.

[0038] Specific usage and beneficial effects of the present invention:

[0039] When the hydraulic cylinder is in use, the oil port 8 is connected to the pressure oil of the external hydraulic system, and oil is supplied to the oil inlet chamber through the oil port 8, so as to drive multiple plunger rods 5 to move synchronously under the action of the external guide component. The hydraulic cylinder decomposes the traditional single plunger rod 5 into multiple ones, and seals and guides the multiple plunger rods 5 respectively through the cooperation of multiple groups of internal guide components, so that the force of the hydraulic cylinder is more uniform when in use, and the plunger rod 5 has no contact with the inside of the oil inlet chamber. It only needs to fine-process the surface of the plunger rod 5 to ensure the sealing performance, which reduces the processing difficulty and has a longer sealing life; the overall movement of the plunger rod 5 is guided by the external guide sleeve 4, and the ability to resist eccentric load and lateral force is stronger, so that when it is installed in a non-vertical manner, it is not easy for the plunger rod 5 to bend downward due to its own weight, which effectively avoids the uneven force when the plunger rod 5 contacts the annular cylinder body and causes unilateral wear of the contact surface, thereby greatly improving the service life of the hydraulic cylinder. Especially for the use conditions of long-stroke hydraulic cylinders, since the internal and external guiding methods increase the piston rod rigidity and the ability to resist offset load and lateral force, the stroke of the hydraulic cylinder can be made longer and the service life of the hydraulic cylinder is also improved.

[0040] The annular cylinder body in the hydraulic cylinder forms an annular cavity structure through the cooperation of the first cylinder head 1, the second cylinder head 9, the inner cylinder 10 and the outer cylinder 3, so that the hydraulic cylinder can pass the mandrel of the mechanical equipment through the mandrel hole 6 when in use, and can be used for load lifting conditions, expanding the scope of use of the plunger hydraulic cylinder. The mandrel hole 6 can also be used to thread cables or other components. Compared with traditional external cables, the hydraulic cylinder can protect the cables when threading them, reduce the wear of the moving part of the cables when the hydraulic cylinder is in use, effectively increase the service life of the cables, and make the appearance of the mechanical equipment more beautiful and practical.

[0041] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments. On the basis of the present invention, some modifications or improvements can be made thereto, which is obvious to those skilled in the art. Therefore, these modifications or improvements made on the basis of not departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

Claims

1. A multi-rod plunger long-stroke hollow hydraulic cylinder, characterized in that: Included are: An annular cylinder body, the annular cylinder body comprising an oil inlet chamber, the annular cylinder body being provided with an oil port (8) communicating with the oil inlet chamber, and the end of the annular cylinder body being provided with a plurality of groups of holes evenly arranged in an annular direction and communicating with the oil inlet chamber; The plunger rod (5) is provided with the same number of groups as the holes, and is respectively slidably arranged along its axis and penetrated into the plurality of groups of holes; An external guide assembly is fixedly connected to the ends of the plurality of groups of plunger rods (5) and guides the plunger rods (5) externally along the outer cylinder wall of the annular cylinder body; and The inner guide components are provided in a plurality of groups and are respectively arranged in the plurality of groups of holes and connected to the plurality of groups of plunger rods (5) to guide the plunger rods (5) internally.

2. A multi-rod plunger long-stroke hollow hydraulic cylinder according to claim 1, characterized in that: The annular cylinder comprises: A first cylinder head (1), wherein a second cylinder head (9) is arranged in parallel with an interval on one side of the first cylinder head (1); An inner cylinder barrel (10), both ends of which are respectively sealed and fixedly connected to the first cylinder head (1) and the first cylinder head (1); and The outer cylinder (3) has two ends which are respectively sealed and fixedly connected to the first cylinder head (1) and the first cylinder head (1), and is sleeved on the inner cylinder (10) to form an annular cavity for the plunger rod (5) to move.

3. A multi-rod plunger long-stroke hollow hydraulic cylinder according to claim 2, characterized in that: The first cylinder head (1) and the second cylinder head (9) are annular in shape, and the inner cylinder barrel (10) is a hollow structure and is connected to the center holes of the first cylinder head (1) and the second cylinder head (9) to cooperate to form a core shaft hole (6).

4. The multi-rod plunger long-stroke hollow hydraulic cylinder according to claim 1, characterized in that: The outer guide assembly comprises an outer guide sleeve (4), which is cylindrical and slidably sleeved on the annular cylinder body along its axis. The ends of the plurality of groups of plunger rods (5) are fixedly connected to the outer guide sleeve (4).

5. The multi-rod plunger long-stroke hollow hydraulic cylinder according to claim 1, characterized in that: The inner guide assembly comprises: An inner guide sleeve (7) is disposed in the oil inlet chamber and communicated with the hole, and the plunger rod (5) is slidably disposed in the inner guide sleeve (7); and A sealing member is arranged in the inner guide sleeve (7) and contacts the outer wall of the plunger rod (5) so as to seal the gap between the plunger rod (5) and the inner guide sleeve (7).

6. The multi-rod plunger long-stroke hollow hydraulic cylinder according to claim 1, characterized in that: A mounting flange (2) is provided at the end of the annular cylinder.

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