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CN-122014715-A - Flexible sequential telescopic oil cylinder and multi-stage oil cylinder combination

CN122014715ACN 122014715 ACN122014715 ACN 122014715ACN-122014715-A

Abstract

A flexible sequential telescopic cylinder and multi-stage cylinder combination belongs to the technical field of engineering machinery and is characterized in that a rear valve body is fixedly arranged at the tail of a cylinder body, a rear valve core is arranged on the rear valve body, a rear valve sleeve is sleeved outside the rear valve core in a sliding mode, a return spring is arranged between the rear valve sleeve and the cylinder body, one end of a central tube is fixedly connected with the rear valve sleeve, the other end of the central tube penetrates through a piston and a piston rod, a variable-section valve port with a continuously variable flow area is formed between the rear valve core and the rear valve sleeve when the rear valve sleeve axially moves, an inlet of the variable-section valve port is communicated with a large cavity oil port of the cylinder body, an outlet of the variable-section valve port is communicated with a central tube central oil channel and is used for being communicated with a large cavity of a next-stage cylinder, when the present-stage cylinder extends to the end of stroke, the piston axially moves against the pretightening force of the return spring through the central tube, the variable-section valve port gradually increases the flow entering the next-stage cylinder with displacement, and accordingly the flow of the variable-section valve port gradually increases in order, and flexible sequential extension of the next-stage cylinder is achieved.

Inventors

  • ZHANG QI
  • LI TIANFU
  • YU SHAOMENG
  • SUN FENG

Assignees

  • 江苏宏昌天马物流装备有限公司

Dates

Publication Date
20260512
Application Date
20260318

Claims (10)

  1. 1. The utility model provides a flexible order flexible hydro-cylinder, includes cylinder body (6), piston (5), piston rod (10) and piston rod head (11), its characterized in that still includes: The rear valve body (2) is fixedly arranged at the tail part of the cylinder body (6); the rear valve core (1) is fixedly arranged on the rear valve body (2); The rear valve sleeve (4) is axially sleeved outside the rear valve core (1) in a sliding manner; The reset spring (3) is arranged between the rear valve sleeve (4) and the tail of the cylinder body (6) and is used for providing a pre-tightening force for enabling the rear valve sleeve (4) to be compressed towards the rear valve core (1); One end of the central tube (7) is fixedly connected with the rear valve sleeve (4), the other end of the central tube axially slides and penetrates through the piston (5) and the piston rod (10), and the end part and the piston (5) form transmission fit in the axial direction; a variable cross-section valve port with a continuously variable flow area when the rear valve sleeve (4) axially moves is formed between the outer wall of the rear valve core (1) and the inner wall of the rear valve sleeve (4) by arranging a combined groove structure with the cross-sectional area changing along the axial direction; the inlet of the variable-section valve port is communicated with a large cavity oil port on the cylinder body (6), the outlet of the variable-section valve port is communicated with a central oil duct of the central pipe (7), and the outlet of the variable-section valve port is communicated with a large cavity of a next-stage oil cylinder through an oil port on the piston rod head (11); When the primary oil cylinder extends to the end of the stroke, the piston (5) drives the rear valve sleeve (4) to overcome the pretightening force of the return spring (3) through the central tube (7) so that the flow area of the variable-section valve port gradually increases along with displacement, the flow entering the next-stage oil cylinder correspondingly gradually increases, and the flexible sequential extension of the next-stage oil cylinder is realized.
  2. 2. A flexible sequential telescopic ram according to claim 1, characterized in that the cross-sectional area of the combined groove structure is continuously varied in the axial direction, so that the flow area S (Δx) of the variable section valve port and the axial displacement Δx of the rear valve sleeve (4) satisfy S (Δx) =k·Δx, where k is a constant.
  3. 3. The flexible sequential telescopic cylinder according to claim 2, wherein the combined groove structure is a plurality of U-shaped combined grooves distributed along the circumferential direction of the rear valve core (1), and each U-shaped combined groove is formed by sequentially connecting a plurality of U-shaped grooves with gradually changed groove widths and/or groove depths along the axial direction.
  4. 4. The flexible sequential telescoping cylinder of claim 2, wherein said combination groove structure is a combination groove with a fold line variation in axial cross section.
  5. 5. The flexible sequential telescopic cylinder according to claim 1, wherein the rear valve body (2) is further provided with: The first check valve (15) is arranged on a channel which is communicated with the inlet of the variable-section valve port and the large cavity of the oil cylinder and is used for supplying oil to the large cavity of the oil cylinder in a one-way manner; And the inlet of the check valve II (16) is communicated with the central oil duct of the central pipe (7) through an oil way in the rear valve body (2), and the outlet of the check valve II is communicated with the large cavity oil port of the oil cylinder and is used for conducting oil flowing back from the large cavity of the lower-stage oil cylinder through the central oil duct of the central pipe (7).
  6. 6. A flexible sequential expansion cylinder according to claim 1, characterized in that a constant differential pressure reducing valve (17) is connected in series to the inlet oil path of the variable cross-section valve port, for maintaining the pressure difference between the front and rear of the variable cross-section valve port constant.
  7. 7. The flexible sequential telescoping cylinder as claimed in claim 1, further comprising a stroke valve (13) mounted on said piston rod head (11), wherein the ports of said stroke valve (13) are respectively in communication with the cylinder large chamber and the large chamber ports of said next stage cylinder for conducting the oil return path of said cylinder large chamber upon triggering.
  8. 8. A flexible sequential telescopic ram according to claim 7, characterized in that the stroke valve (13) is provided with a stroke valve rod (12) for conducting, the stroke valve rod (12) extending outside the piston rod head (11) for cooperating with a stop (20) on an adjacent ram to trigger the stroke valve (13) to conduct.
  9. 9. A multi-stage cylinder combination comprising at least two stages of cylinders sequentially connected, wherein each of the cylinders other than the last stage is the flexible sequential telescopic cylinder according to any one of claims 1 to 8.
  10. 10. The combination of claim 9, wherein the last cylinder is a flexible sequential telescopic cylinder as claimed in any one of claims 1 to 8, and the stroke valve on the piston rod head thereof is in a normally open state.

Description

Flexible sequential telescopic oil cylinder and multi-stage oil cylinder combination Technical Field The invention relates to a flexible sequential telescopic cylinder and multi-stage cylinder combination, and belongs to the technical field of engineering machinery. Background The sequential telescopic control of the multi-stage arm support of the crane relates to the safe control of lifting capacity of the lifting arm, reducing the stress of the whole structure and perfecting the force limit anti-tipping algorithm, is one of the core technologies of the arm support crane, and the function is mainly realized by the sequential telescopic control of the arm support oil cylinders of all stages. In the prior art, sequential expansion and contraction of the arm support multi-stage oil cylinders are usually realized by arranging sequence valves among all stages of oil cylinders. The method has the problems of large pressure loss, difficult adjustment, high cost and the like. Meanwhile, in the action process of the existing sequential telescopic cylinder, the phenomena of large system impact, severe arm support shaking and the like generally exist, and the stability and reliability of the arm support action are seriously affected. Disclosure of Invention Aiming at the defects of the prior crane multi-stage boom cylinder sequential expansion control technology, the invention provides a flexible sequential expansion cylinder and multi-stage cylinder combination, which has the advantages of simple structure, stable operation and high reliability. In order to achieve the above purpose, the technical scheme of the invention is as follows: in one aspect, the invention provides a flexible sequential telescopic cylinder, which comprises a cylinder body, a piston rod and a piston rod head, and is characterized by further comprising: the rear valve body is used as an independent body and is fixedly arranged at the tail part of the cylinder body; The rear valve core is fixedly arranged on the rear valve body; The rear valve sleeve is axially sleeved outside the rear valve core in a sliding manner; the reset spring is arranged between the rear valve sleeve and the tail part of the cylinder body and is used for providing a pretightening force for pressing the rear valve sleeve towards the rear valve core; one end of the central tube is fixedly connected with the rear valve sleeve, the other end of the central tube axially slides and penetrates through the piston and the piston rod, and the end part and the piston form transmission fit in the axial direction; The variable cross-section valve port with the continuously variable flow area when the rear valve sleeve axially moves is formed by arranging a combined groove structure with the cross-sectional area axially changing between the outer wall of the rear valve core and the inner wall of the rear valve sleeve; The inlet of the variable-section valve port is communicated with a large cavity oil port on the cylinder body, the outlet of the variable-section valve port is communicated with a central oil duct of the central pipe, and the outlet of the variable-section valve port is communicated with a large cavity of the next-stage oil cylinder through an oil port on the piston rod head; When the primary oil cylinder extends to the end of the stroke, the piston drives the rear valve sleeve to axially move by overcoming the pretightening force of the return spring through the central tube, so that the flow area of the variable-section valve port gradually increases along with displacement, the flow entering the next-stage oil cylinder correspondingly gradually increases, and the flexible sequential extension of the next-stage oil cylinder is realized. Further, the cross-sectional area of the combined groove structure is continuously changed along the axial direction, so that the flow area S (delta x) of the variable-section valve port and the axial displacement delta x of the rear valve sleeve satisfy the following conditions: S(Δx) = k·Δx (1) Where k is a constant. Further, the reset spring enables the rear valve sleeve to be tightly matched with the rear valve core, and the sealing conical surfaces of the rear valve sleeve and the rear valve core have a tendency of forming sealing fit. Further, the combined groove structure is a plurality of U-shaped combined grooves distributed along the circumferential direction of the rear valve core, and each U-shaped combined groove is formed by sequentially connecting a plurality of U-shaped grooves with groove widths and/or groove depths which gradually change along the axial direction. Further, each U-shaped combined groove is formed by sequentially connecting 4U-shaped grooves d1, U-shaped grooves m1, U-shaped grooves e1 and U-shaped grooves n1, wherein the groove widths and the groove depths of the U-shaped grooves d1, U-shaped grooves m1, U-shaped grooves e1 and U-shaped grooves n1 are gradually increased from the rear valve core to th