CN112431811A - Double-cylinder combined type multi-stage bolt hydraulic cylinder - Google Patents

Double-cylinder combined type multi-stage bolt hydraulic cylinder Download PDF

Info

Publication number
CN112431811A
CN112431811A CN202011398935.1A CN202011398935A CN112431811A CN 112431811 A CN112431811 A CN 112431811A CN 202011398935 A CN202011398935 A CN 202011398935A CN 112431811 A CN112431811 A CN 112431811A
Authority
CN
China
Prior art keywords
cylinder barrel
stage
rear end
wall
cavity
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202011398935.1A
Other languages
Chinese (zh)
Inventor
回子健
刘庆教
张虹源
金全明
汤宝石
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Xuzhou XCMG Hydraulics Co Ltd
Original Assignee
Xuzhou XCMG Hydraulics Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Xuzhou XCMG Hydraulics Co Ltd filed Critical Xuzhou XCMG Hydraulics Co Ltd
Priority to CN202011398935.1A priority Critical patent/CN112431811A/en
Publication of CN112431811A publication Critical patent/CN112431811A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/08Characterised by the construction of the motor unit
    • F15B15/14Characterised by the construction of the motor unit of the straight-cylinder type
    • F15B15/1423Component parts; Constructional details
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/08Characterised by the construction of the motor unit
    • F15B15/14Characterised by the construction of the motor unit of the straight-cylinder type
    • F15B15/1423Component parts; Constructional details
    • F15B15/1428Cylinders
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/08Characterised by the construction of the motor unit
    • F15B15/14Characterised by the construction of the motor unit of the straight-cylinder type
    • F15B15/16Characterised by the construction of the motor unit of the straight-cylinder type of the telescopic type

Abstract

The invention discloses a double-cylinder combined type multi-stage bolt hydraulic cylinder. The inner wall of the front end of the first-stage cylinder barrel is provided with an inner step, and the inner step is in sliding fit with the second-stage cylinder barrel; the outer wall of the rear end of the second-stage cylinder barrel is provided with an outer step, and the outer step is in sliding fit with the inner wall of the first-stage cylinder barrel; the inner wall of the front end of the secondary cylinder barrel is connected with a guide sleeve, and the inner wall of the rear end of the secondary cylinder barrel is connected with a hollow nut; the ball head type piston rod is slidably arranged in the guide sleeve, and the rear end of the ball head type piston rod is provided with a piston; a small cavity oil port A and a large cavity oil port B are formed in the first-stage cylinder barrel; an outer cavity D is formed between the first-stage cylinder barrel and the second-stage cylinder barrel, an inner cavity E is formed between the second-stage cylinder barrel and the ball-head type piston rod, and an inner oil duct C communicated with the outer cavity D and the inner cavity E is formed in the second-stage cylinder barrel. The invention adopts a multi-stage telescopic structure, reduces the occupied space and meets the requirement of large stroke; the one-level cylinder is integrative with the outside uide bushing, and the second grade cylinder is integrative with inboard piston, practices thrift the inner space to the rifle drilling of being convenient for processes, reduces the radial size of cylinder.

Description

Double-cylinder combined type multi-stage bolt hydraulic cylinder
Technical Field
The invention belongs to the technical field of hydraulic cylinders, and particularly relates to a double-cylinder combined type multi-stage bolt hydraulic cylinder.
Background
The bolt oil cylinder is an auxiliary hydraulic cylinder frequently used in engineering machinery, and not only needs to bear a part of gravity load of a main machine during working, but also needs to bear additional working load during working of the main machine, so that the requirement on stability and reliability is high. It is this specific operating condition that determines this type of hydraulic cylinder can not have too big pneumatic cylinder stroke, and the common appearance structure gives short, little sight to people. However, in many cases, the short stroke cannot meet the requirement of the main engine, and for a general oil cylinder, increasing the stroke of the hydraulic cylinder will result in increasing the total length of the oil cylinder, but for many main engines with harsh installation space requirements, this is undoubtedly a contradictory practice. Therefore, the hydraulic cylinder is required to have a stroke which can meet the working requirement of the main engine on the premise of limited installation space.
For example, the safe and reliable lifting multi-stage cylinder (CN 105298981A) disclosed in the Chinese patent comprises a cylinder body, a first-stage piston rod, a second-stage piston rod and a third-stage piston rod which are sequentially arranged from outside to inside, wherein a rear end cover is fixed at the rear end of the cylinder body, a first rod cavity is formed between the cylinder body and the first-stage piston rod, a second rod cavity is formed between the first-stage piston rod and the second-stage piston rod, a third rod cavity is formed between the second-stage piston rod and the third-stage piston rod, and a rodless cavity is formed inside the third-stage piston rod.
The defects of the prior art are as follows:
by adopting a multi-stage telescopic structure, although the extension length is ensured, the radial size is increased, the weight of the oil cylinder is increased, the loss of the light weight increases the production cost of the main engine, and the market competitiveness of the main engine is very unfavorable.
Disclosure of Invention
In order to solve the technical problem, the invention provides a double-cylinder combined type multi-stage bolt hydraulic cylinder.
The invention is realized by the following technical scheme: a double-cylinder combined type multistage bolt hydraulic cylinder is characterized in that an end cover is installed at the rear end of a primary cylinder barrel in a threaded connection mode, and a secondary cylinder barrel is sleeved in the primary cylinder barrel; the inner wall of the front end of the first-stage cylinder barrel is provided with an inner step, the inner step is in sliding fit with the second-stage cylinder barrel, and a guide sealing part matched with the second-stage cylinder barrel is arranged on the inner step; the outer wall of the rear end of the second-stage cylinder barrel is provided with an outer step, the outer step is in sliding fit with the inner wall of the first-stage cylinder barrel, and a guide sealing part matched with the inner wall of the first-stage cylinder barrel is arranged on the outer step; the inner wall of the front end of the secondary cylinder barrel is connected with a guide sleeve, and the inner wall of the rear end of the secondary cylinder barrel is connected with a hollow nut; the ball head type piston rod is slidably arranged in the guide sleeve, and the rear end of the ball head type piston rod is provided with a piston; the piston is in sliding fit with the inner wall of the secondary cylinder barrel, and the rear end of the piston is opposite to the hollow nut; a small cavity oil port A and a large cavity oil port B are formed in the first-stage cylinder barrel; an outer cavity D is formed between the first-stage cylinder barrel and the second-stage cylinder barrel, an inner cavity E is formed between the second-stage cylinder barrel and the ball-head type piston rod, and an inner oil duct C communicated with the outer cavity D and the inner cavity E is formed in the second-stage cylinder barrel.
It further comprises the following steps: the rear end of the primary cylinder barrel is provided with a stepped inner spigot, the front end of the end cover is provided with a stepped outer spigot, the outer spigot of the end cover is connected and installed in the inner spigot of the primary cylinder barrel through threads, and an O-shaped ring seal is installed between the outer spigot of the end cover and the inner spigot of the primary cylinder barrel; the end cover is fixed with the rear end of the first-stage cylinder barrel through screws.
The front end of the secondary cylinder barrel is provided with a stepped inner spigot, the rear end of the guide sleeve is provided with a stepped outer spigot, and the outer spigot of the guide sleeve is connected and installed in the inner spigot of the secondary cylinder barrel through threads; the inner oil duct C comprises three gun drill holes formed in the second-stage cylinder barrel, and the gun drill holes are parallel to the axis of the second-stage cylinder barrel; the front end of the gun drill hole is communicated to an inner spigot at the front end of the secondary cylinder barrel so as to be communicated with the inner cavity E, the rear end of the gun drill hole is communicated to the rear end face of the secondary cylinder barrel, and the rear end of the gun drill hole is provided with a threaded plug.
An inner thread is formed in an inner hole of the piston, the piston is mounted on an outer thread at the rear end of the ball head type piston rod through the inner thread, and a positioning step is formed in the inner wall of the piston; and a positioning screw is arranged at the bottom of the mounting groove on the outer circumferential surface of the piston.
And a flange is fixed outside the primary cylinder barrel, and a joint seat is fixed outside the small cavity oil port A and the large cavity oil port B.
Compared with the prior art, the invention has the beneficial effects that: the multi-stage telescopic structure is adopted, so that the occupied space is reduced, and the requirement of large-stroke use is met; the first-stage cylinder barrel and the outer guide sleeve are integrated, the second-stage cylinder barrel and the inner piston are integrated, so that the inner space is saved, the gun drilling is facilitated, and the radial size of the cylinder barrel is reduced; the threaded connection type detachable cylinder bottom and the hollow nut facilitate installation of the cylinder barrel and the piston rod, and maintenance is facilitated.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a view taken from the direction A of FIG. 1;
in the figure: 1. a ball head type piston rod; 2. a guide sleeve; 3. a flange; 4. a joint base; 5. a first-stage cylinder barrel; 5-1, inner steps; 6. a second-stage cylinder barrel; 6-1, outer steps; 7. a piston; 8. a hollow nut; 9. an end cap;
the symbols in the figure are as follows: a small cavity oil port A, a large cavity oil port B, an inner oil duct C, an outer cavity D, an inner cavity E, a primary stroke S1 and a secondary stroke S2.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
As shown in fig. 1 and 2, a double-cylinder combined type multistage latch hydraulic cylinder is characterized in that a stepped inner spigot is arranged at the rear end of a primary cylinder 5, a stepped outer spigot is arranged at the front end of an end cover 9, the outer spigot of the end cover 9 is installed in the inner spigot of the primary cylinder 5 through threaded connection, and an O-ring seal is installed between the outer spigot of the end cover 9 and the inner spigot of the primary cylinder 5; the end cover 9 and the rear end of the first-stage cylinder barrel 5 are fixed through screws. The threaded connection type detachable cylinder bottom is convenient for mounting the cylinder barrel and the piston rod, and is beneficial to maintenance and repair.
The inner wall of the front end of the first-stage cylinder barrel 5 is provided with an inner step 5-1, the inner step 5-1 is in sliding fit with the second-stage cylinder barrel 6, the inner step 5-1 is provided with a guide sealing part matched with the second-stage cylinder barrel 6, and the guide sealing part can adopt a sealing ring and a support ring. The outer wall of the rear end of the second-stage cylinder barrel 6 is provided with an outer step 6-1, the outer step 6-1 is in sliding fit with the inner wall of the first-stage cylinder barrel 5, the outer step 6-1 is provided with a guide sealing part matched with the inner wall of the first-stage cylinder barrel 5, and the guide sealing part can adopt a sealing ring and a support ring. The first-stage cylinder barrel is integrated with the outer side guide sleeve, and the second-stage cylinder barrel is integrated with the inner side piston, so that the inner space is saved.
The inner wall of the rear end of the second-stage cylinder barrel 6 is connected with a hollow nut 8, the hollow nut can be disassembled in a threaded connection mode, the cylinder barrel and a piston rod can be conveniently installed, and maintenance is facilitated. The inner wall of the front end of the second-stage cylinder barrel 6 is connected with a guide sleeve 2, the front end of the second-stage cylinder barrel 6 is provided with a stepped inner spigot, the rear end of the guide sleeve 2 is provided with a stepped outer spigot, and the outer spigot of the guide sleeve 2 is installed in the inner spigot of the second-stage cylinder barrel 6 through threaded connection. The ball head type piston rod 1 is slidably arranged in the guide sleeve 2, and the rear end of the ball head type piston rod 1 is provided with a piston 7; the piston 7 is in sliding fit with the inner wall of the second-stage cylinder barrel 6, and the rear end of the piston 7 is opposite to the hollow nut 8. An inner hole of the piston 7 is provided with an internal thread, the piston 7 is arranged on an external thread at the rear end of the ball head type piston rod 1 through the internal thread, and the inner wall of the piston 7 is provided with a positioning step; and a positioning screw is arranged at the bottom of the mounting groove on the outer circumferential surface of the piston 7.
A small cavity oil port A and a large cavity oil port B are formed in the primary cylinder 5; the flange 3 is fixed outside the first-stage cylinder barrel 5, and the joint seats 4 are fixed outside the small cavity oil port A and the large cavity oil port B. An outer cavity D is formed between the first-stage cylinder barrel 5 and the second-stage cylinder barrel 6, an inner cavity E is formed between the second-stage cylinder barrel 6 and the ball-head type piston rod 1, and the inner oil duct C is communicated with the outer cavity D and the inner cavity E. The inner oil duct C comprises three gun drill holes arranged on the second-stage cylinder barrel 6, and the gun drill holes are parallel to the axis of the second-stage cylinder barrel 6; the front end of the gun drill hole is communicated to an inner spigot at the front end of the secondary cylinder 6 and further communicated with the inner cavity E, the rear end of the gun drill hole is communicated to the rear end face of the secondary cylinder 6, and a threaded plug is mounted at the rear end of the gun drill hole. The gun drill hole structure can reduce the radial dimension of the cylinder barrel.
The working principle is as follows:
during operation, the oil from the oil port B of the large cavity is fed to push the second-stage cylinder barrel 6 to move outwards, and the second-stage cylinder barrel 6 which is pushed by oil pressure drives the ball head type piston rod 1 and the piston 7 to move outwards together. When the second-stage cylinder barrel 6 finishes the first-stage stroke S1, the second-stage cylinder barrel stops moving forwards, hydraulic oil continues to push the ball-head type piston rod 1 and the piston 7 to move through the inner hole of the nut, the rod extends outwards relative to the second-stage cylinder barrel 6 at the moment, when the piston 7 is in contact with the guide sleeve 2, the ball-head type piston rod 1 finishes the second-stage stroke S2, and the whole extending process is finished. When the oil cylinder is recycled, hydraulic oil enters the outer cavity D through the cavity oil port A, and the hydraulic oil entering the outer cavity D flows into the inner cavity E through the inner oil port C, so that two-stage recycling is realized.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims (5)

1. A double-cylinder combined multi-stage bolt hydraulic cylinder,
the method is characterized in that:
the rear end of the primary cylinder barrel (5) is provided with an end cover (9) through threaded connection, and the secondary cylinder barrel (6) is sleeved in the primary cylinder barrel (5); the inner wall of the front end of the first-stage cylinder barrel (5) is provided with an inner step (5-1), the inner step (5-1) is in sliding fit with the second-stage cylinder barrel (6), and a guide sealing part matched with the second-stage cylinder barrel (6) is arranged on the inner step (5-1);
the outer wall of the rear end of the secondary cylinder barrel (6) is provided with an outer step (6-1), the outer step (6-1) is in sliding fit with the inner wall of the primary cylinder barrel (5), and a guide sealing part matched with the inner wall of the primary cylinder barrel (5) is arranged on the outer step (6-1); the inner wall of the front end of the secondary cylinder barrel (6) is connected with a guide sleeve (2), and the inner wall of the rear end of the secondary cylinder barrel (6) is connected with a hollow nut (8);
the ball head type piston rod (1) is slidably arranged in the guide sleeve (2), and the rear end of the ball head type piston rod (1) is provided with a piston (7); the piston (7) is in sliding fit with the inner wall of the secondary cylinder barrel (6), and the rear end of the piston (7) is opposite to the hollow nut (8);
a small cavity oil port A and a large cavity oil port B are formed in the primary cylinder barrel (5); an outer cavity D is formed between the first-stage cylinder barrel (5) and the second-stage cylinder barrel (6), an inner cavity E is formed between the second-stage cylinder barrel (6) and the ball-head type piston rod (1), and an inner oil duct C for communicating the outer cavity D with the inner cavity E is formed in the second-stage cylinder barrel (6).
2. The double-cylinder combined multistage latch hydraulic cylinder according to claim 1, characterized in that: the rear end of the primary cylinder barrel (5) is provided with a stepped inner spigot, the front end of the end cover (9) is provided with a stepped outer spigot, the outer spigot of the end cover (9) is connected and installed in the inner spigot of the primary cylinder barrel (5) through threads, and an O-shaped ring seal is installed between the outer spigot of the end cover (9) and the inner spigot of the primary cylinder barrel (5); the end cover (9) is fixed with the rear end of the first-stage cylinder barrel (5) through screws.
3. The double-cylinder combined multistage latch hydraulic cylinder according to claim 1, characterized in that: the front end of the secondary cylinder barrel (6) is provided with a stepped inner spigot, the rear end of the guide sleeve (2) is provided with a stepped outer spigot, and the outer spigot of the guide sleeve (2) is installed in the inner spigot of the secondary cylinder barrel (6) through threaded connection;
the inner oil duct C comprises three gun drill holes formed in the second-stage cylinder barrel (6), and the gun drill holes are parallel to the axis of the second-stage cylinder barrel (6); the front end of the gun drill hole is communicated to the inner spigot of the front end of the secondary cylinder (6) so as to be communicated with the inner cavity E, the rear end of the gun drill hole is communicated to the rear end face of the secondary cylinder (6), and the rear end of the gun drill hole is provided with a threaded plug.
4. The double-cylinder combined multistage latch hydraulic cylinder according to claim 1, characterized in that: an inner hole of the piston (7) is provided with an internal thread, the piston (7) is arranged on an external thread at the rear end of the ball head type piston rod (1) through the internal thread, and the inner wall of the piston (7) is provided with a positioning step; and a positioning screw is arranged at the bottom of the mounting groove on the outer circumferential surface of the piston (7).
5. The double-cylinder combined multistage latch hydraulic cylinder according to claim 1, characterized in that: a flange (3) is fixed outside the first-stage cylinder barrel (5), and a joint seat (4) is fixed outside the small cavity oil port A and the large cavity oil port B.
CN202011398935.1A 2020-12-04 2020-12-04 Double-cylinder combined type multi-stage bolt hydraulic cylinder Pending CN112431811A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202011398935.1A CN112431811A (en) 2020-12-04 2020-12-04 Double-cylinder combined type multi-stage bolt hydraulic cylinder

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202011398935.1A CN112431811A (en) 2020-12-04 2020-12-04 Double-cylinder combined type multi-stage bolt hydraulic cylinder

Publications (1)

Publication Number Publication Date
CN112431811A true CN112431811A (en) 2021-03-02

Family

ID=74691869

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202011398935.1A Pending CN112431811A (en) 2020-12-04 2020-12-04 Double-cylinder combined type multi-stage bolt hydraulic cylinder

Country Status (1)

Country Link
CN (1) CN112431811A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113606220A (en) * 2021-06-07 2021-11-05 中国北方车辆研究所 Multi-stage oil cylinder with forward and backward oil filling ports fixed on outer cylinder

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102852896A (en) * 2012-07-26 2013-01-02 沈姝君 Double-action multistage hydraulic oil cylinder with solid piston rod
CN103939416A (en) * 2014-05-13 2014-07-23 张振宇 Multistage double-action reciprocating cylinder device
CN105298981A (en) * 2015-10-12 2016-02-03 江苏恒立高压油缸股份有限公司 Safe and reliable derrick lifting multistage cylinder
CN110410381A (en) * 2019-08-14 2019-11-05 北京特种机械研究所 A kind of heavy duty multistage composite telescopic hydraulic cylinder
CN209976958U (en) * 2019-01-28 2020-01-21 韩志引 Pure-step hydraulic multistage lifting type oil cylinder
CN211501168U (en) * 2019-10-28 2020-09-15 牡丹江盛泰汽车制造有限公司 Pure-step hydraulic multistage lifting type oil cylinder

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102852896A (en) * 2012-07-26 2013-01-02 沈姝君 Double-action multistage hydraulic oil cylinder with solid piston rod
CN103939416A (en) * 2014-05-13 2014-07-23 张振宇 Multistage double-action reciprocating cylinder device
CN105298981A (en) * 2015-10-12 2016-02-03 江苏恒立高压油缸股份有限公司 Safe and reliable derrick lifting multistage cylinder
CN209976958U (en) * 2019-01-28 2020-01-21 韩志引 Pure-step hydraulic multistage lifting type oil cylinder
CN110410381A (en) * 2019-08-14 2019-11-05 北京特种机械研究所 A kind of heavy duty multistage composite telescopic hydraulic cylinder
CN211501168U (en) * 2019-10-28 2020-09-15 牡丹江盛泰汽车制造有限公司 Pure-step hydraulic multistage lifting type oil cylinder

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113606220A (en) * 2021-06-07 2021-11-05 中国北方车辆研究所 Multi-stage oil cylinder with forward and backward oil filling ports fixed on outer cylinder

Similar Documents

Publication Publication Date Title
CN104006032B (en) The locked oil hydraulic cylinder of a kind of two-way mechanical
CN102434530A (en) Differential-type plunger composite oil cylinder
CN112431811A (en) Double-cylinder combined type multi-stage bolt hydraulic cylinder
CN204664046U (en) A kind of compression type environmental sanitation boats and ships Double Acting Telescopic Hydraulic Cylinder
CN116641939A (en) Hydro-cylinder buffer gear
CN211623864U (en) Plunger piston composite double-acting oil cylinder
CN203978999U (en) Can bear larger side to the hydraulic jack of pressure
CN204061405U (en) Double-action passing hole type level Four oil cylinder
CN212202270U (en) Wear-reducing piston assembly convenient to maintain
CN207111580U (en) Self-adapting type piston rod and piston coupling structure
CN219865708U (en) Novel hydraulic cylinder capable of preventing piston rod from rotating
CN202926747U (en) Hydraulic cylinder and pumping device comprising same
CN215370408U (en) Plunger type hydraulic oil cylinder with mechanical locking and positioning functions
CN215950020U (en) Long-stroke two-stage hydraulic cylinder
CN214092534U (en) Second-stage oil cylinder with semicircular groove on guide sleeve
CN218509858U (en) Three-stage equal-thrust hydraulic cylinder
CN210423239U (en) Lifting oil cylinder
CN216842478U (en) Two-stage hydraulic cylinder easy to machine
CN220435156U (en) Telescopic oil cylinder of petroleum drilling machine
CN214092531U (en) Secondary oil cylinder with rectangular groove on guide sleeve
CN202625730U (en) Oil jack with pneumatic pump
CN213540917U (en) Hydraulic steel ball hinge type piston connecting structure
CN218440016U (en) Steering power cylinder
CN218207310U (en) Long-stroke disorder-prevention two-stage hydraulic cylinder
CN217271121U (en) Built-in hollow oil cylinder

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
RJ01 Rejection of invention patent application after publication
RJ01 Rejection of invention patent application after publication

Application publication date: 20210302