CN117703861A

CN117703861A - Swing hydraulic cylinder

Info

Publication number: CN117703861A
Application number: CN202311807394.7A
Authority: CN
Inventors: 何忠秋; 蔡国英; 邱苏红; 杜雄; 汪学栋; 房小艳
Original assignee: Shanghai Machine Tool Factory Co Ltd
Current assignee: Shanghai Machine Tool Factory Co Ltd
Priority date: 2023-12-26
Filing date: 2023-12-26
Publication date: 2024-03-15

Abstract

The invention discloses a swing hydraulic cylinder, which relates to the technical field of hydraulic cylinders and comprises a body shell and a main shaft, wherein the main shaft penetrates through a front end cover and stretches into a body shell cavity, a moving blade is fixedly sleeved in the middle of the part of the main shaft, an oil cylinder movable cavity matched with the moving blade is arranged in the middle of the body shell cavity, a fixed blade matched with the moving blade is fixedly sleeved in the oil cylinder movable cavity and used for limiting the rotating angle of the moving blade, a vertical oil inlet channel, a horizontal oil inlet channel, a buffer mechanism and a driving mechanism are sequentially arranged on two sides of the body shell cavity from top to bottom, the horizontal oil inlet channel is used for improving the rotating speed of the moving blade, the driving mechanism is used for providing power when the rotating stroke of the moving blade starts, the buffer mechanism is used for providing buffer force when the rotating stroke of the moving blade ends, hydraulic noise and impact generated when the moving blade rotates to be close to the fixed blade are avoided, and the working precision and the service life of the swing hydraulic cylinder are improved.

Description

Swing hydraulic cylinder

Technical Field

The invention relates to the technical field of hydraulic cylinders, in particular to a swinging hydraulic cylinder.

Background

The hydraulic cylinder has the characteristics of simple structure, easy manufacture, reliable work, convenient arrangement and the like, and is widely applied to hydraulic systems. Hydraulic cylinders can be largely classified into piston cylinders, plunger cylinders, swing cylinders, and special cylinders as actuators of hydraulic systems. The swing cylinder is used for converting hydraulic energy into rotation mechanical energy smaller than 360 degrees, and is characterized by large output torque, low-speed rotation, good controllability and low efficiency.

The swing cylinders widely used at present are all vane type, and patent CN204164078U discloses a universal swing hydraulic cylinder, which comprises a support, wherein an inner spherical surface is formed inside the support, and a first oil port and a second oil port are arranged outside the support; a cylinder body having an outer spherical surface universally fitted with the inner spherical surface of the support; a rotating shaft, on which a moving blade is fixed; the fixed vane divides the inner cavity of the cylinder body into two independent chambers, a first oil hole and a second oil hole are formed in the fixed vane, the outer side end of the first oil hole is communicated with the first oil hole, the inner side end of the first oil hole is communicated with one chamber, the outer side end of the second oil hole is communicated with the second oil hole, and the inner side end of the second oil hole is communicated with the other chamber; locking mechanical system, it includes the holding screw of spiro union on the support and sets up on the cylinder body with the contact patch of cylinder body and support locking when receiving the holding screw to compress tightly, can adjust the angle of the inside pivot of cylinder body according to the installation needs, but above-mentioned scheme does not set up buffer, when the moving blade rotates to laminating stator vane, can produce hydraulic noise, and the collision of moving blade and stator vane can produce the impact to influence the operating accuracy and the life of swing pneumatic cylinder.

Disclosure of Invention

In view of the above, the present invention provides a swing hydraulic cylinder to solve the above-mentioned problems in the prior art.

In order to achieve the above object, the present invention provides the following technical solutions:

the utility model provides a swing pneumatic cylinder, includes body shell and main shaft, body shell front end is equipped with the front end housing, and the rear end is equipped with the rear end cap, the main shaft runs through the front end cap stretches into in the body shell cavity, main shaft stretches into the fixed cover in part intermediate position and is equipped with the moving blade, body shell cavity intermediate position be equipped with the hydro-cylinder movable cavity of moving blade looks adaptation, the hydro-cylinder movable cavity internal fixation be equipped with moving blade looks adaptation's stator blade for the restriction moving blade turned angle, body shell cavity both sides are equipped with vertical oil feed passageway, horizontal oil feed passageway, buffer gear and actuating mechanism from top to bottom in proper order, vertical oil feed passageway runs through horizontal oil feed passageway and buffer gear and intercommunication actuating mechanism, horizontal oil feed passageway buffer gear and actuating mechanism all communicate hydro-cylinder movable cavity, horizontal oil feed passageway is used for promoting moving blade turned velocity, actuating mechanism is used for providing moving blade power when turning stroke begins, buffer gear is used for providing the power of moving blade when turning end.

Further, the movable cavity of the oil cylinder is formed by enclosing a sealing ring, a first sealing ring and a second sealing ring, the inner ring of the sealing ring, the first sealing ring and the second sealing ring are matched with the moving blades, the sealing ring is fixedly arranged at the middle position in the cavity of the body shell, the first sealing ring is sleeved on the main shaft at one side of the moving blades, the second sealing ring is sleeved on the main shaft at the other side of the moving blades, and the fixed blades are fixedly arranged at the inner sides of the sealing rings.

Further, the outer end of the transverse oil inlet channel is provided with an oil plug I, the middle of the transverse oil inlet channel is communicated with the vertical oil inlet channel, and the inner end of the transverse oil inlet channel penetrates through the sealing ring and is communicated with the movable cavity of the oil cylinder.

Further, the buffer mechanism comprises a transverse second pressure oil connecting channel located between the transverse oil inlet channel and the driving mechanism, an oil plug II is arranged at the outer end of the transverse second pressure oil connecting channel, the middle of the transverse second pressure oil connecting channel is communicated with the vertical oil inlet channel, the inner end of the transverse second pressure oil connecting channel penetrates through the sealing ring and is communicated with the movable cavity of the oil cylinder, triangular grooves are formed in two sides of the axial surface of the moving blade, and when the side surface of the moving blade is attached to the side surface of the fixed blade, the triangular grooves close to the fixed blade can be communicated with the transverse second pressure oil connecting channel.

Further, the actuating mechanism is including being located the horizontal first pressure oil connecting channel of buffer gear below, horizontal first pressure oil connecting channel outer end has the screw plug through threaded connection, and the inner is the oil pipe way, be equipped with the axial hole in the screw plug, axial hole one end intercommunication vertical oil feed passageway, the other end intercommunication the oil pipe way, be equipped with pressure oil connecting channel one in the stator blade, pressure oil connecting channel one end with stator blade side parallel and level and intercommunication hydro-cylinder movable cavity, the other end runs through pressure oil connecting channel two the sealing washer and communicates the oil pipe way, be equipped with in the axial hole only to the check valve that hydro-cylinder movable cavity direction circulated.

Further, the check valve comprises a steel ball, a spring and a throttle plug, wherein a second hole and a first hole are sequentially formed in the axial hole from inside to outside, the aperture of the second hole is larger than that of the first hole, the inner end of the second hole is communicated with the oil passage, the outer end of the second hole is communicated with the first hole, the first hole is communicated with the vertical oil inlet passage, the second hole is in threaded connection with the throttle plug at the communication position of the oil passage, the throttle plug is provided with a central hole for communicating the second hole with the oil passage, the spring is located at Kong Erna, one end of the spring is fixedly connected with the throttle plug, the other end of the spring is fixedly connected with the steel ball, and the steel ball is used for plugging the communication position of the first hole and the second hole.

Further, a small hole restrictor is arranged in a channel penetrating through the sealing ring at the inner end of the transverse second pressure oil connecting channel.

Further, sealing devices are arranged at the joint of the front end cover and the body shell and the joint of the rear end cover and the body shell, and a felt ring is arranged at the position of an inner hole of the front end cover and used for sealing the main shaft.

Further, two ends of the main shaft extending part are connected with the inner wall of the cavity of the body shell through rolling bearings, and the rolling bearings are used for supporting the main shaft.

The invention has the beneficial effects that:

according to the invention, the transverse oil inlet channel is used for improving the rotating speed of the moving blade, namely, the rotating speed of the moving blade and the output torque can be adjusted, the driving mechanism is used for providing power when the rotating stroke of the moving blade starts, the buffer mechanism is used for providing buffer force when the rotating stroke of the moving blade ends, hydraulic noise and impact generated when the moving blade rotates to be close to a fixed blade are avoided, and the working precision and the service life of the swing hydraulic cylinder are improved; the movable cavity of the oil cylinder is formed by enclosing a sealing ring, a first sealing ring and a second sealing ring, and the gap between the first sealing ring and the moving blade and the gap between the second sealing ring and the moving blade can be adjusted by changing the thickness of the first sealing ring or the second sealing ring; when the moving blade rotates to be positioned above the transverse oil inlet channel, pressure oil is directly pumped into the movable cavity of the oil cylinder through the transverse oil inlet channel and acts on the side surface of the moving blade, so that the rotating speed of the moving blade is increased, and the working efficiency is improved; when the moving blade rotates to the side surface close to the side surface of the fixed blade, pressure oil flows into a transverse second pressure oil connecting channel through a gap formed by the triangular groove and the sealing ring, so that the moving blade rotates to the final position of the fixed blade; when the side surface of the moving blade is jointed with the side surface of the fixed blade, the transverse oil inlet channel is blocked, pressure oil is pumped into the movable cavity of the oil cylinder through the axial hole of the threaded plug by the first pressure oil connecting channel and acts on the side surface of the moving blade, so that the moving blade is driven to start rotating; the second hole is in threaded connection with the throttle plug at the communication position of the oil passage, and the pressure acting on the steel ball can be adjusted by changing the position of the throttle plug, so that the pressure difference between the front and the rear of the steel ball is changed; a small hole restrictor is arranged in a channel penetrating through the sealing ring at the inner end of the transverse second pressure oil connecting channel, so that slow gradually-to-fast action switching is further realized; the main shaft is supported by the rolling bearing, so that the stability of the main shaft is improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only embodiments of the present invention, and that other drawings can be obtained according to the provided drawings without inventive effort for a person skilled in the art.

Fig. 1 is a front cross-sectional view of a first embodiment of a swing cylinder according to the present invention.

Fig. 2 is a cross-sectional view taken along A-A of fig. 1.

Fig. 3 is a front cross-sectional view of a second embodiment of a swing cylinder according to the present invention.

Wherein, in the figure:

1-a body shell; 2-a main shaft; 3-moving blades; 4, fixing the blades; 5-a sealing ring; 6-a rear end cover; 7-rolling bearings; 8-a first sealing ring; 9-a second sealing ring; 10-a front end cover; 11-oil plug I; 12-an oil plug II; 13-a threaded plug; 14-steel balls; 15-a spring; 16-a throttle plug; 101-a vertical oil inlet channel; 102-a transverse oil inlet passage; 103-a transverse first pressure oil connection channel; 104-a second pressure oil connecting channel; 105-a transverse second pressure oil connection channel; 401-pressure oil connection channel one.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely, and it is apparent that the described embodiments are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

It should be noted that the terms "first," "second," and the like in the description and claims of the present application and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate in order to describe the embodiments of the present application described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

In the present application, the terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate an azimuth or a positional relationship based on that shown in the drawings. These terms are used primarily to better describe the present application and its embodiments and are not intended to limit the indicated device, element or component to a particular orientation or to be constructed and operated in a particular orientation.

Also, some of the terms described above may be used to indicate other meanings in addition to orientation or positional relationships, for example, the term "upper" may also be used to indicate some sort of attachment or connection in some cases. The specific meaning of these terms in this application will be understood by those of ordinary skill in the art as appropriate.

Furthermore, the terms "mounted," "configured," "provided," "connected," "coupled," and "sleeved" are to be construed broadly. For example, it may be a fixed connection, a removable connection, or a unitary construction; may be a mechanical connection, or an electrical connection; may be directly connected, or indirectly connected through intervening media, or may be in internal communication between two devices, elements, or components. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art as the case may be.

Example 1:

referring to fig. 1-2, this embodiment discloses a swing hydraulic cylinder, including body shell 1 and main shaft 2, body shell 1 front end is equipped with front end cover 10, the rear end is equipped with rear end cover 6, main shaft 2 runs through front end cover 10 and stretches into in body shell 1 cavity, main shaft 2 stretches into partial intermediate position fixed cover and is equipped with moving blade 3, moving blade 3 links firmly in main shaft 2 through the screw in this implementation in the partial intermediate position that stretches into, body shell 1 cavity intermediate position is equipped with the hydro-cylinder movable cavity with moving blade 3 looks adaptation, the hydro-cylinder movable cavity is internal fixed be equipped with moving blade 3 looks adaptation stator blade 4, be used for limiting moving blade 3 rotation angle, body shell 1 cavity both sides are equipped with vertical oil feed passageway 101 from top to bottom in proper order, horizontal oil feed passageway 102, buffer gear and actuating mechanism, vertical oil feed passageway 101 runs through horizontal oil feed passageway 102 and buffer gear and communicates actuating mechanism, horizontal oil feed passageway 102, buffer gear and actuating mechanism all communicate hydro-cylinder movable cavity, horizontal oil feed passageway 102 is used for promoting moving blade 3 rotation speed, actuating mechanism is used for providing moving blade 3 rotation start time power, buffer gear is used for providing moving blade 3 rotation time and is used for providing and moving blade 3 rotation time and is close to the rotational torque of moving blade 3 and the hydraulic pressure of the moment that can be produced by the hydraulic cylinder is close to the rotational accuracy of moving blade 3 and the hydraulic cylinder is improved to the rotational accuracy is produced and is small in the hydraulic cylinder rotation time and is suitable for the moment 4 is used for and to the moment to be improved.

The movable cavity of the oil cylinder is surrounded by a sealing ring 5, a sealing ring I8 and a sealing ring II 9, the inner ring of the sealing ring 5, the sealing ring I8 and the sealing ring II 9 are all matched with the moving blade 3, the sealing ring 5 is fixedly arranged at the middle position in the cavity of the body shell 1, the sealing ring I8 is sleeved on the main shaft 2 at one side of the moving blade 3, the sealing ring II 9 is sleeved on the main shaft 2 at the other side of the moving blade 3, and the gap between the sealing ring I8 and the moving blade 3 and the gap between the sealing ring II 9 and the moving blade 3 can be adjusted by changing the thickness of the sealing ring I8 or the sealing ring II 9;

the fixed vane 4 is fixedly arranged on the inner side of the sealing ring 5, in this embodiment, the radius of the inner arc surface of the fixed vane 4 is the same as the outer diameter of the middle position of the extending part of the main shaft 2, the radius of the outer arc surface of the fixed vane 4 is the same as the inner radius of the sealing ring 5, and the fixed vane 4 is fixed below the inner circle of the sealing ring 5 after the screw is arranged on the bottom surface of the body shell 1 and sequentially penetrates through the body shell 1 and the sealing ring 5.

The outer end of the transverse oil inlet channel 102 is provided with an oil plug 11, the middle is communicated with the vertical oil inlet channel 101, and the inner end penetrates through the sealing ring 5 and is communicated with the movable cavity of the oil cylinder. When the moving blade 3 rotates to be located above the transverse oil inlet channel 102, pressure oil is directly pumped into the movable cavity of the oil cylinder through the transverse oil inlet channel 102 and acts on the side surface of the moving blade 3, so that the rotating speed of the moving blade 3 is increased, and the working efficiency is improved.

The buffer mechanism comprises a transverse second pressure oil connecting channel 105 positioned between a transverse oil inlet channel 102 and the driving mechanism, an oil plug II 12 is arranged at the outer end of the transverse second pressure oil connecting channel 105, the middle is communicated with a vertical oil inlet channel 101, the inner end penetrates through a sealing ring 5 and is communicated with an oil cylinder movable cavity, triangular grooves are formed in two sides of the axial surface of a moving blade 3, when the side surface of the moving blade 3 is in contact with the side surface of a fixed blade 4, the triangular grooves close to the fixed blade 4 can be communicated with the transverse second pressure oil connecting channel 105, namely, when the moving blade 3 rotates to the side surface of the moving blade close to the side surface of the fixed blade 4, pressure oil flows into the transverse second pressure oil connecting channel 105 through a gap formed by the triangular grooves and the sealing ring 5, and the moving blade 3 rotates to the buffer of the final position of the side surface in contact with the side surface of the fixed blade 4 is realized.

The driving mechanism comprises a transverse first pressure oil connecting channel 103 positioned below the buffering mechanism, one end of the transverse first pressure oil connecting channel 103 is connected with a threaded plug 13 through threads, the other end of the transverse first pressure oil connecting channel is an oil passage pipeline, an axial hole is formed in the threaded plug 13, one end of the axial hole is communicated with a vertical oil inlet channel 101, the other end of the axial hole is communicated with the oil passage pipeline, a first pressure oil connecting channel 401 is arranged in the fixed blade 4, one end of the first pressure oil connecting channel 401 is flush with the side surface of the fixed blade 4 and is communicated with an oil cylinder movable cavity, the other end of the first pressure oil connecting channel penetrates through a sealing ring 5 through a second pressure oil connecting channel 104 and is communicated with the oil passage pipeline, and a one-way valve which can only circulate towards the direction of the oil cylinder movable cavity is arranged in the axial hole. When the side surface of the moving blade 3 is jointed with the side surface of the fixed blade 4, the transverse oil inlet passage 102 is blocked, pressure oil is pumped into the movable cavity of the oil cylinder through the axial hole of the threaded plug 13 by the first pressure oil connecting passage 401 and acts on the side surface of the moving blade 3, so that the moving blade 3 is driven to start rotating.

The one-way valve comprises a steel ball 14, a spring 15 and a throttle plug 16, wherein a second hole and a first hole are sequentially formed in the axial hole from inside to outside, the aperture of the second hole is larger than that of the first hole, the inner end of the second hole is communicated with a communication oil pipeline, the outer end of the second hole is communicated with the first communication hole, the hole is communicated with a vertical oil inlet channel 101, the second hole is in threaded connection with the throttle plug 16 at the communication position of the communication oil pipeline, the throttle plug 16 is provided with a central hole for communicating the second hole with the communication oil pipeline, the spring 15 is positioned in the second hole, one end of the spring 15 is fixedly connected with the throttle plug 16, the other end of the spring 15 is fixedly connected with the steel ball 14, the steel ball 14 is used for blocking the communication position of the first hole and the second hole, and the pressure acting on the steel ball 14 can be adjusted by changing the position of the throttle plug 16, so that the pressure difference between the front and the back of the steel ball 14 is changed.

The joint of the front end cover 10 and the body shell 1 and the joint of the rear end cover 6 and the body shell 1 are both provided with sealing devices, the front end cover 10 is a transparent cover, and the inner hole position of the front end cover 10 is provided with a felt ring for sealing the main shaft 2.

The two ends of the extending part of the main shaft 2 are connected with the inner wall of the cavity of the body shell 1 through rolling bearings 7, and the rolling bearings 7 are used for supporting the main shaft 2 and improving the stability of the main shaft.

The working principle of the invention is as follows:

when the moving blade 3 rotates clockwise relative to the fixed blade 4, the left side surface of the moving blade 3 is attached to the left side surface of the fixed blade 4 in the initial stage, at this time, the left side transverse oil inlet channel 102 is blocked by the moving blade 3, pressure oil is pumped by the left side vertical oil inlet channel 101, most of the pressure oil flows into the inner hole I of the left side threaded plug 13 and pushes the left side steel ball 14 to flow into the left side hole II and flow through the center hole of the left side throttling plug 16, and then the left side pressure oil connecting channel II 104 and the left side pressure oil connecting channel I401 push the moving blade 3 to rotate clockwise relative to the fixed blade 4, so that the swing of the main shaft 2 is started in the initial position;

when the main shaft 2 swings for a certain angle, the moving blade 3 rotates to be positioned above the left lateral oil inlet channel 102, and pressure oil pumped by the left vertical oil inlet channel 101 directly enters an oil cylinder movable cavity between the left side surface of the moving blade 3 and the left side surface of the fixed blade 4 from the left lateral oil inlet channel 102 and does not pass through the left threaded plug 13, so that the rotating speed of the moving blade 3 is accelerated;

the main shaft 2 continues to swing, the angle between the right side surface of the moving blade 3 and the right side surface of the fixed blade 4 becomes smaller, when the moving blade 3 seals the right side transverse oil inlet channel 102, and when the triangular groove on the moving blade 3 is communicated with the right side transverse second pressure oil connecting channel 105, the pressure oil between the right side surface of the moving blade 3 and the right side surface of the fixed blade 4 flows out from the right side transverse second pressure oil connecting channel 105 through the gap formed by the triangular groove and the sealing ring 5, and the moving blade 3 rotates to a position close to the final stroke position until the right side surface of the moving blade 3 is attached to the right side surface of the fixed blade 4.

The counter-clockwise rotation of the rotor blade 3 relative to the stator blade 4 is referred to above.

Example 2:

referring to fig. 3, the difference between the present embodiment and embodiment 1 is that a small hole restrictor is provided in the passage penetrating the seal ring 5 at the inner end of the transverse second pressure oil connecting passage 105, so as to further enhance the buffering effect of the rotation of the moving blade 3 to the position close to the final stroke; meanwhile, in the process of pushing the moving blade 3 to rotate, the switching from the oil inlet of the transverse first pressure oil connecting channel 103 and the oil inlet of the transverse second pressure oil connecting channel 105 to the oil inlet of the transverse oil inlet channel 102 is realized, so that the moving blade 3 is gradually switched from a slow speed to a fast speed.

The foregoing description is only of the preferred embodiments of the present application and is not intended to limit the same, but rather, various modifications and variations may be made by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. The utility model provides a swing hydraulic cylinder, its characterized in that includes body shell (1) and main shaft (2), body shell (1) front end is equipped with front end housing (10), and the rear end is equipped with rear end housing (6), main shaft (2) run through front end housing (10) stretches into in body shell (1) cavity, main shaft (2) stretches into partial intermediate position fixed cover and is equipped with moving blade (3), body shell (1) cavity intermediate position be equipped with moving blade (3) looks adaptation hydro-cylinder movable cavity, hydro-cylinder movable cavity internal fixation be equipped with moving blade (3) looks adaptation stationary vane (4) for restriction moving blade (3) rotation angle, body shell (1) cavity both sides are from top to bottom equipped with vertical oil feed channel (101), horizontal oil feed channel (102), buffer gear and actuating mechanism in proper order, vertical oil feed channel (101) run through horizontal oil feed channel (102) and buffer gear and intercommunication actuating mechanism, horizontal oil feed channel (102) and moving blade (3) are used for when the actuating mechanism all moving blade (3) are used for beginning rotation speed when moving blade (3) are rotated, the damping mechanism is used for providing damping force at the end of the rotating stroke of the moving blade (3).

2. The swing hydraulic cylinder according to claim 1, wherein the movable cavity of the oil cylinder is surrounded by a sealing ring (5), a first sealing ring (8) and a second sealing ring (9), the inner ring of the sealing ring (5), the first sealing ring (8) and the second sealing ring (9) are matched with the moving blade (3), the sealing ring (5) is fixedly arranged at the middle position in the cavity of the body shell (1), the first sealing ring (8) is sleeved on the main shaft (2) at one side of the moving blade (3), the second sealing ring (9) is sleeved on the main shaft (2) at the other side of the moving blade (3), and the fixed blade (4) is fixedly arranged at the inner side of the sealing ring (5).

3. A swinging hydraulic cylinder according to claim 2, characterized in that the outer end of the transverse oil inlet channel (102) is provided with an oil plug (11), the middle is communicated with the vertical oil inlet channel (101), and the inner end penetrates through the sealing ring (5) and is communicated with the movable cavity of the oil cylinder.

4. A swinging hydraulic cylinder according to claim 2, characterized in that the buffer mechanism comprises a transverse second pressure oil connecting channel (105) between the transverse oil inlet channel (102) and the driving mechanism, the outer end of the transverse second pressure oil connecting channel (105) is provided with an oil plug two (12), the middle is communicated with the vertical oil inlet channel (101), the inner end penetrates through the sealing ring (5) and is communicated with the movable cavity of the oil cylinder, triangular grooves are arranged on two sides of the axial surface of the moving blade (3), and when the side surface of the moving blade (3) is in contact with the side surface of the fixed blade (4), the triangular grooves close to the fixed blade (4) can be communicated with the transverse second pressure oil connecting channel (105).

5. The swing hydraulic cylinder according to claim 2, wherein the driving mechanism comprises a transverse first pressure oil connecting channel (103) located below the buffering mechanism, a threaded plug (13) is connected to the outer end of the transverse first pressure oil connecting channel (103) through threads, an oil through pipe is arranged at the inner end of the transverse first pressure oil connecting channel, an axial hole is formed in the threaded plug (13), one end of the axial hole is communicated with the vertical oil inlet channel (101), the other end of the axial hole is communicated with the oil through pipe, a first pressure oil connecting channel (401) is arranged in the fixed vane (4), one end of the first pressure oil connecting channel (401) is flush with the side face of the fixed vane (4) and is communicated with the movable cavity of the oil cylinder, the other end of the first pressure oil connecting channel penetrates through the sealing ring (5) through a second pressure oil connecting channel (104) and is communicated with the oil through pipe, and a one-way valve which can only circulate towards the direction of the movable cavity of the oil cylinder is arranged in the axial hole.

6. The swing hydraulic cylinder according to claim 5, wherein the one-way valve comprises a steel ball (14), a spring (15) and a throttle plug (16), the axial hole is sequentially provided with a hole two and a hole one from inside to outside, the hole two has a larger diameter than the hole one, the inner end of the hole two is communicated with the oil through pipe, the outer end of the hole one is communicated with the vertical oil inlet channel (101), the thread connection of the communication position of the hole two and the oil through pipe is provided with a center hole for communicating the hole two and the oil through pipe, the spring (15) is positioned at Kong Erna, one end of the spring (15) is fixedly connected with the throttle plug (16), the other end of the spring is fixedly connected with the steel ball (14), and the steel ball (14) is used for sealing the communication position of the hole one and the hole two.

7. A swinging hydraulic cylinder according to claim 4, characterized in that a small orifice restrictor is provided in the passage of the inner end of the transverse second pressure oil connection passage (105) through the sealing ring (5).

8. A swing hydraulic cylinder according to claim 1, wherein sealing means are provided at the connection of the front end cover (10) and the body casing (1) and at the connection of the rear end cover (6) and the body casing (1), and a felt ring is provided at the inner hole of the front end cover (10) for sealing the main shaft (2).

9. A swing hydraulic cylinder according to claim 1, wherein both ends of the projecting portion of the main shaft (2) are connected to the inner wall of the cavity of the body housing (1) via rolling bearings (7), the rolling bearings (7) being for supporting the main shaft (2).