CN210599660U - Single-action multistage hydraulic oil cylinder - Google Patents
Single-action multistage hydraulic oil cylinder Download PDFInfo
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- CN210599660U CN210599660U CN201921392194.9U CN201921392194U CN210599660U CN 210599660 U CN210599660 U CN 210599660U CN 201921392194 U CN201921392194 U CN 201921392194U CN 210599660 U CN210599660 U CN 210599660U
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Abstract
The utility model relates to a multi-stage hydraulic cylinder of nonoculture belongs to hydraulic machine technical field. The utility model discloses need not bore the oilhole again on the lateral wall of each grade cylinder, but set up the oil passageway at the piston support ring for the bulge position of cylinder outer wall, fluid between each grade cylinder and the cylinder can carry out oil through the oil passageway of crossing on the piston support ring, has guaranteed promptly that the motion of hydro-cylinder is steady reliable, has reduced present piston support ring again in the motion by the scratch, scrape the rotten condition, very big increase the life of hydro-cylinder. Different piston support rings and oil passing areas can be replaced according to actual requirements of products, and the ascending and descending speeds of the multistage hydraulic oil cylinder are controlled.
Description
Technical Field
The utility model relates to a multi-stage hydraulic cylinder of nonoculture belongs to hydraulic machine technical field.
Background
The multi-stage hydraulic cylinder is an important actuating mechanism in engineering machinery, is particularly suitable for being used on the conditions that the installation position is limited and the stroke requirement is large, and mainly comprises a single-acting multi-stage hydraulic cylinder and a double-acting hydraulic cylinder in terms of motion control. The single-acting multi-stage oil cylinder is an execution structure which is lifted by utilizing hydraulic oil and retracted by utilizing the self gravity of a load. The ascending and descending speed control is controlled by drilling a plurality of oil passing holes on the cylinder barrel of each stage. Taking the three-stage hydraulic oil cylinder in the prior art shown in fig. 1 as an example, the structure of the three-stage hydraulic oil cylinder comprises an outer cylinder end cover, an outer cylinder, a first-stage cylinder, a second-stage cylinder and a final-stage cylinder; the end parts of the first-stage cylinder barrel, the second-stage cylinder barrel and the last-stage cylinder barrel are sequentially provided with oil passing channels relative to the inner end surface of the outer cylinder barrel end cover; piston support rings are respectively arranged at the inner ends of the outer side walls of the first-stage cylinder barrel, the second-stage cylinder barrel and the last-stage cylinder barrel; oil passing holes are respectively formed in the side walls of the first-stage cylinder barrel, the second-stage cylinder barrel and the last-stage cylinder barrel. When the multi-stage cylinder is lifted, after hydraulic oil enters from the oil port, the hydraulic oil passes through the oil passage f, the oil passage e and the oil passage d at the end part of the cylinder barrel, the cylinder barrels of each stage are lifted in sequence, and the hydraulic oil between the cylinder barrels of each stage is discharged from the oil passage g, the oil passage h and the oil passage i in sequence during lifting; when the multi-stage cylinder retracts, hydraulic oil is conveyed to the position between the cylinder barrels of each stage from the oil passing hole i, the oil passing hole h and the oil passing hole g in sequence. When the piston moves every time, the piston support rings are inevitably scratched, the service life of the piston support rings is shortened, and the service life of the whole oil cylinder is influenced. From the above analysis, it can be known that the size and position of the oil passing hole on the side wall of each stage of the cylinder barrel of the multistage cylinder can seriously affect the service life of the piston and piston support ring, thereby affecting the service life of the whole oil cylinder. And its size and position of this oil passing hole just are relatively fixed after processing, in the maintenance and the use in later stage, can't change and adjust according to actual demand.
SUMMERY OF THE UTILITY MODEL
The utility model discloses the technical problem that will solve is: the single-action multistage hydraulic oil cylinder is provided, the ascending and descending speeds of the oil cylinder are stable and reliable, and the service life of the hydraulic oil cylinder is prolonged.
The utility model provides a technical scheme that its technical problem adopted is: single-action multistage hydraulic cylinder, including outer cylinder and hydraulic fluid port, outer cylinder endotheca is equipped with multistage cylinder, the fixed outer cylinder end cover that is provided with of outer cylinder one end, the other end has the guiding hole that supplies multistage cylinder to make reciprocating motion, multistage cylinder includes last cylinder and middle cylinder, middle cylinder is one or more, the outer end of last cylinder has sealed end, the hydraulic fluid port sets up in the position that can communicate last cylinder inner chamber, the one end of cylinder at each level of multistage cylinder near outer cylinder end cover all is fixed at the cylinder outer wall and is provided with the piston support ring, the piston support ring sets up for the cylinder outer wall protrusion of its position, the outer disc of piston support ring contacts with the cylinder inner wall of its position, the piston support ring is offered the oil passageway of crossing that runs through piston support ring both sides terminal surface for the protruding.
Further, the method comprises the following steps: the oil passage on the piston support ring is an arc-shaped groove formed in the position of the outer circular surface of the piston support ring.
Further, the method comprises the following steps: the arc-shaped grooves are arranged in a plurality at intervals along the circumferential direction of the piston support ring.
Further, the method comprises the following steps: a plurality of piston support rings are arranged on the outer wall of the same cylinder barrel side by side.
Further, the method comprises the following steps: the piston support ring is made of nodular cast iron.
Further, the method comprises the following steps: outer limiting clamping rings A are arranged at the outer end of the inner wall of the outer cylinder barrel and the outer end of the inner wall of the middle cylinder barrel, outer limiting clamping rings B are arranged at the inner end of the outer wall of the middle cylinder barrel and the inner end of the outer wall of the last-stage cylinder barrel, and the outer limiting clamping rings A and the outer limiting clamping rings B are matched to control the stroke of the multi-stage cylinder when the multi-stage.
Further, the method comprises the following steps: an inner limiting clamping ring A is arranged at the inner end of the inner wall of the middle cylinder barrel, an inner limiting clamping ring B is arranged at the inner end of the outer wall of the middle cylinder barrel and the inner end of the outer wall of the final-stage cylinder barrel, and the inner limiting clamping ring A and the inner limiting clamping ring B are matched to control the stroke of the multi-stage cylinder during retraction.
Further, the method comprises the following steps: in the multi-stage cylinder, the stroke of the first-stage middle cylinder barrel during retraction is limited through the inner end surface of the end cover of the outer cylinder barrel, and the strokes of the other cylinder barrels during retraction are limited through the matching of the inner limiting clamping ring A and the inner limiting clamping ring B.
Further, the method comprises the following steps: the oil port is arranged on the end cover of the outer cylinder barrel; grooves are arranged at the position of the inner end face of the middle cylinder barrel and the position of the inner end face of the last-stage cylinder barrel and serve as oil passing channels.
Further, the method comprises the following steps: the piston support ring is arranged by adopting a detachable connecting structure. The piston support ring is provided with an opening on the annular side wall and is clamped in the annular groove on the outer wall of the cylinder barrel.
The utility model has the advantages that: the oil hole does not need to be drilled on the side wall of each stage of the cylinder barrel, the oil passage is arranged at the protruding part of the piston support ring relative to the outer wall of the cylinder barrel, and oil can pass through the oil passage on the piston support ring, so that the stability and reliability of the motion of the oil cylinder are ensured, the condition that the existing piston support ring is scratched and broken in the motion is reduced, and the service life of the oil cylinder is greatly prolonged. Different piston support rings and oil passing areas can be replaced according to actual requirements of products, and the ascending and descending speeds of the multistage hydraulic oil cylinder are controlled.
Drawings
FIG. 1 is a schematic view of an assembly structure of a multi-stage hydraulic oil cylinder at one end provided with a piston support ring in the prior art;
FIG. 2 is a schematic view of the overall structure of the multi-stage hydraulic cylinder of the present invention;
FIG. 3 is a schematic view of an assembly structure of a middle multi-stage hydraulic cylinder of the present invention at one end provided with a piston support ring;
FIG. 4 is a schematic structural view of a piston support ring;
fig. 5 is a schematic sectional view taken along line a-a of fig. 4.
Labeled as: 1-outer cylinder barrel, 2-first-stage cylinder barrel, 3-second-stage cylinder barrel, 4-last-stage cylinder barrel, 5-first-stage piston support ring, 6-second-stage piston support ring, 7-last-stage piston support ring, 8-outer cylinder barrel end cover, 9-oil port, 10-sealing end, 11-outer limiting retainer ring A, 12-outer limiting retainer ring B, 13-inner limiting retainer ring A, 14-inner limiting retainer ring B, 15-oil passing channel a, 16-oil passing channel B, 17-oil passing channel c, 18-oil passing channel d, 19-oil passing channel e, 20-oil passing channel f, 21-oil passing hole g, 22-oil passing hole h and 23-oil passing hole i.
Detailed Description
The present invention will be further explained with reference to the drawings and the embodiments.
As shown in fig. 2 to 5, the utility model comprises an outer cylinder barrel 1 and an oil port 9, a multi-stage cylinder is sleeved in the outer cylinder barrel 1, an outer cylinder barrel end cover 8 is fixedly arranged at one end of the outer cylinder barrel 1, the other end has the guiding hole that supplies multistage cylinder to make reciprocating motion, multistage cylinder includes final stage cylinder 4 and middle cylinder, middle cylinder is one or more, the outer end of final stage cylinder 4 has sealed end 10, hydraulic fluid port 9 sets up in the position that can communicate 4 inner chambers of final stage cylinder, the cylinder of each stage of multistage cylinder is all at the fixed piston support ring that is provided with of cylinder outer wall near the one end of outer cylinder end cover 8, the piston support ring sets up for the cylinder outer wall protrusion of its position, the excircle face of piston support ring contacts with the cylinder inner wall of its position, the piston support ring is offered the oil passing channel who runs through piston support ring both sides terminal surface for the protruding position of cylinder outer wall.
When implementing, oil feed and the sharing hydraulic fluid port 9 of producing oil, the utility model discloses all can be suitable for at various multistage hydraulic cylinder, for example second grade jar, tertiary jar, level four jar, five-stage jar etc. decide as required. For ease of understanding, the following description will be given by way of example with a three-stage cylinder. For the third-level cylinder, two middle cylinder barrels are included, namely a first-level cylinder barrel 2 and a second-level cylinder barrel 3, and a last-level cylinder barrel 4 is equivalent to the third-level cylinder barrel. The piston support ring arranged between the first-stage cylinder barrel 2 and the outer cylinder barrel 1 is a first-stage piston support ring 5, the piston support ring arranged between the second-stage cylinder barrel 3 and the first-stage cylinder barrel 2 is a second-stage piston support ring 6, and the piston support ring arranged between the last-stage cylinder barrel 4 and the second-stage cylinder barrel 3 is a last-stage piston support ring 7. An oil passage a15 is arranged on the primary piston supporting ring 5, an oil passage b16 is arranged on the secondary piston supporting ring 6, and an oil passage c17 is arranged on the tertiary piston supporting ring 7. The channel between the inner end face of the first-stage cylinder 2 and the outer cylinder end cover 8 is set as an oil passing channel d18, the channel between the inner end face of the second-stage cylinder 3 and the outer cylinder end cover 8 is set as an oil passing channel e19, and the channel between the inner end face of the last-stage cylinder 4 and the outer cylinder end cover 8 is set as an oil passing channel f 20.
When the multi-stage cylinder is lifted, after hydraulic oil enters from the oil port 9, the hydraulic oil passes through the oil passing channel f20, the oil passing channel e19 and the oil passing channel d18 at the end part of the cylinder barrel, the cylinder barrels of each stage are lifted in sequence, and the hydraulic oil between the cylinder barrels of each stage is discharged from the oil passing channel a15, the oil passing channel b16 and the oil passing channel c17 in sequence during lifting; when the multi-stage cylinder retracts, hydraulic oil is sequentially supplied to the space between the cylinder barrels of each stage from the oil passage c17, the oil passage b16 and the oil passage a 15. The piston support ring moves on the inner surface of the cylinder barrel smoothly and stably every time of movement, and the material of the piston support ring can be a ball-milling cast iron material with wear resistance. The service lives of the first-stage piston support ring 5, the second-stage piston support ring 6 and the final-stage piston support 7 are greatly prolonged, so that the service life of the whole oil cylinder is prolonged.
The oil passage which is arranged on the protruding part of the piston support ring relative to the outer wall of the cylinder barrel can be of a groove structure or a through hole structure. For the processing design, the utility model discloses the oil passageway of crossing on piston support ring is preferably the arc wall of seting up in piston support ring's outer disc position. The arc-shaped groove means that the contour line of the cross section of the groove is arc-shaped. In order to improve the stability of the working structure, a plurality of arc-shaped grooves are arranged at intervals along the circumferential direction of the piston support ring and are arranged at intervals as uniform as possible. In specific implementation, the total oil passing area is designed according to the actual product requirement. In this embodiment, the total oil passing area of the piston support ring is composed of the cross-sectional areas of 8 arc-shaped grooves which are equal. The total oil passing area can be designed according to the requirements of actual products, so that different use requirements are met.
In addition, as required, a plurality of piston support rings can be arranged on the outer wall of the same cylinder barrel side by side, and in the embodiment, two piston support rings are arranged on the outer wall of each stage of the cylinder barrel side by side.
In order to control the motion stroke of the multi-stage cylinder conveniently, the outer end of the inner wall of the outer cylinder barrel 1 and the outer end of the inner wall of the middle cylinder barrel are provided with outer limit clamping rings A11, the inner end of the outer wall of the middle cylinder barrel and the inner end of the outer wall of the last stage cylinder barrel 4 are provided with outer limit clamping rings B12, and the outer limit clamping rings A11 and the outer limit clamping rings B12 are matched for controlling the stroke of the multi-. An inner limit retainer ring A13 is arranged at the inner end of the inner wall of the middle cylinder barrel, an inner limit retainer ring B14 is arranged at the inner end of the outer wall of the middle cylinder barrel and the inner end of the outer wall of the final-stage cylinder barrel 4, and the inner limit retainer ring A13 and the inner limit retainer ring B14 are matched for controlling the stroke of the multi-stage cylinder during retraction. In the multi-stage cylinder, the stroke of the first-stage middle cylinder barrel during retraction can be limited through a limiting clamping ring, and can also be limited through the inner end surface of the outer cylinder barrel end cover 8. In this embodiment, the stroke of the first-stage intermediate cylinder during retraction is limited by the inner end face of the outer cylinder end cover 8, and the stroke of the other cylinders during retraction is limited by the cooperation of the inner limiting retainer ring a13 and the inner limiting retainer ring B14. Taking the third-stage cylinder in the embodiment as an example, when the third-stage cylinder extends, after oil is input from the oil port 9, the pressure oil pushes the first-stage cylinder barrel 2 first, and after the outer limit retainer ring B12 on the first-stage cylinder barrel 2 is contacted and clamped with the outer limit retainer ring a11 of the outer cylinder barrel 1, the oil pushes the second-stage cylinder barrel 3 to move; after the outer limit retainer ring B12 on the second-stage cylinder barrel 3 is contacted and clamped with the outer limit retainer ring A11 of the first-stage cylinder barrel 2, the oil pushes the last-stage cylinder barrel 4 to move; and waiting until the outer limit retainer ring A12 on the last stage cylinder barrel 4 is contacted and clamped with the outer limit retainer ring A11 of the second stage cylinder barrel 3, the multi-stage cylinder is completely extended and moves to the maximum stroke. When retracting, the load can firstly push the final stage cylinder barrel 4 to retract, and after the inner limit retainer ring B14 on the final stage cylinder barrel 4 is contacted and clamped with the inner limit retainer ring A13 of the secondary cylinder barrel 3, the load then pushes the secondary cylinder barrel 3 to move; after the inner limiting retainer ring B14 on the second-stage cylinder barrel 3 is contacted and clamped with the inner limiting retainer ring A13 of the first-stage cylinder barrel 2, the load pushes the first-stage cylinder barrel 2 to move, the oil cylinder retracts completely, and oil in the multi-stage cylinder returns to the oil tank from the oil port 9.
The oil port 9 is arranged on the outer cylinder barrel 1 or the outer cylinder barrel end cover 8 or the sealing end head 10, and for convenient implementation, the oil port 9 in the embodiment is arranged on the outer cylinder barrel end cover 8 and is preferably arranged at the central hole position.
In order to enable the oil cylinder to respond quickly, grooves are arranged on the inner end face of the middle cylinder barrel and the inner end face of the last-stage cylinder barrel 4 to serve as oil passing channels.
The piston support ring preferably adopts the detachable connection structure, and different piston support rings and oil passing areas can be replaced according to actual requirements of products, so that the ascending and descending speeds of the multi-stage oil cylinder are controlled. The preferred installation mode is as follows: the piston support ring is provided with an opening on the annular side wall and is clamped in the annular groove on the outer wall of the cylinder barrel. During assembly, taking the primary piston support ring 5 and the primary cylinder barrel 2 as an example, firstly, the primary piston support ring 5 is assembled in an annular groove of the primary cylinder barrel 2, and then, a special shaping tool with a cone is adopted to shape the outer diameter of the primary piston support ring 5, so that the primary piston support ring can be assembled in the outer cylinder barrel 1; when the piston support ring is disassembled, the piston support ring is convenient to disassemble due to the opening. The mode is convenient to assemble, disassemble and replace and high in efficiency.
Claims (10)
1. Single-action multistage hydraulic cylinder, including outer cylinder (1) and hydraulic fluid port (9), outer cylinder (1) endotheca is equipped with multistage jar, outer cylinder (1) one end is fixed to be provided with outer cylinder end cover (8), the other end has the guiding hole that supplies multistage jar to make reciprocating motion, multistage jar includes last cylinder (4) and middle cylinder, middle cylinder is one or more, the outer end of last cylinder (4) has seal end (10), hydraulic fluid port (9) set up in the position that can communicate last cylinder (4) inner chamber, the one end of cylinder at different levels of multistage jar being close to outer cylinder end cover (8) all is provided with piston support ring at the fixed cylinder outer wall, piston support ring sets up for the cylinder outer wall protrusion of its position, the outer disc of piston support ring contacts with the cylinder inner wall of its position, its characterized in that: the piston support ring is provided with an oil passage penetrating through the end faces of the two sides of the piston support ring relative to the protruding part of the outer wall of the cylinder barrel.
2. A single-acting, multi-stage hydraulic ram as claimed in claim 1, wherein: the oil passage on the piston support ring is an arc-shaped groove formed in the position of the outer circular surface of the piston support ring.
3. A single-acting, multi-stage hydraulic ram as claimed in claim 2, wherein: the arc-shaped grooves are arranged in a plurality at intervals along the circumferential direction of the piston support ring.
4. A single-acting, multi-stage hydraulic ram as claimed in claim 1, wherein: a plurality of piston support rings are arranged on the outer wall of the same cylinder barrel side by side.
5. A single-acting, multi-stage hydraulic ram as claimed in claim 1, wherein: the piston support ring is made of nodular cast iron.
6. A single-acting, multi-stage hydraulic ram as claimed in any one of claims 1 to 5, wherein: outer limiting clamping rings A (11) are arranged at the outer end of the inner wall of the outer cylinder barrel (1) and the outer end of the inner wall of the middle cylinder barrel, outer limiting clamping rings B (12) are arranged at the inner end of the outer wall of the middle cylinder barrel and the inner end of the outer wall of the last-stage cylinder barrel (4), and the outer limiting clamping rings A (11) and the outer limiting clamping rings B (12) are matched to control the stroke of the multi-stage cylinder when the multi.
7. A single-acting, multi-stage hydraulic ram as claimed in any one of claims 1 to 5, wherein: an inner limiting retainer ring A (13) is arranged at the inner end of the inner wall of the middle cylinder barrel, an inner limiting retainer ring B (14) is arranged at the inner end of the outer wall of the middle cylinder barrel and the inner end of the outer wall of the final-stage cylinder barrel (4), and the inner limiting retainer ring A (13) and the inner limiting retainer ring B (14) are matched to control the stroke of the multi-stage cylinder during retraction.
8. A single-acting, multi-stage hydraulic ram as claimed in claim 7, wherein: in the multi-stage cylinder, the stroke of the first-stage middle cylinder barrel during retraction is limited through the inner end surface of the outer cylinder barrel end cover (8), and the stroke of the other cylinder barrels during retraction is limited through the matching of the inner limiting clamp ring A (13) and the inner limiting clamp ring B (14).
9. A single-acting, multi-stage hydraulic ram as claimed in any one of claims 1 to 5, wherein: the oil port (9) is arranged on the outer cylinder end cover (8); grooves are arranged at the position of the inner end face of the middle cylinder barrel and the position of the inner end face of the last-stage cylinder barrel (4) and are used as oil passing channels.
10. A single-acting, multi-stage hydraulic ram as claimed in any one of claims 1 to 5, wherein: the piston support ring is arranged by adopting a detachable connection structure; the piston support ring is provided with an opening on the annular side wall and is clamped in the annular groove on the outer wall of the cylinder barrel.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921392194.9U CN210599660U (en) | 2019-08-26 | 2019-08-26 | Single-action multistage hydraulic oil cylinder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921392194.9U CN210599660U (en) | 2019-08-26 | 2019-08-26 | Single-action multistage hydraulic oil cylinder |
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| Publication Number | Publication Date |
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| CN210599660U true CN210599660U (en) | 2020-05-22 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201921392194.9U Active CN210599660U (en) | 2019-08-26 | 2019-08-26 | Single-action multistage hydraulic oil cylinder |
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| CN (1) | CN210599660U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110397643A (en) * | 2019-08-26 | 2019-11-01 | 四川优机实业股份有限公司 | Single-acting multistage hydraulic cylinder |
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2019
- 2019-08-26 CN CN201921392194.9U patent/CN210599660U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110397643A (en) * | 2019-08-26 | 2019-11-01 | 四川优机实业股份有限公司 | Single-acting multistage hydraulic cylinder |
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