CN201391501Y

CN201391501Y - Buffering hydraulic cylinder

Info

Publication number: CN201391501Y
Application number: CN200920019621U
Authority: CN
Inventors: 周元聪
Original assignee: Jinan Dongao Automatic Control Technology Co Ltd
Current assignee: Jinan Dongao Automatic Control Technology Co Ltd
Priority date: 2009-03-26
Filing date: 2009-03-26
Publication date: 2010-01-27
Anticipated expiration: 2019-03-26

Abstract

The utility model discloses a buffering hydraulic cylinder, comprising piston rod, a front cover, a cylinder body, a piston and a rear cover. The piston is provided with a valve chamber penetrating through the piston; the valve chamber is internally provided with a moveable buffering component longer than the valve chamber. The buffering component comprises a buffering plunger piston and two limiting structures fixed on the buffering plunger piston; the buffering plunger piston is sealed and matched with the middle chamber hole liquid of the valve chamber; and the buffering plunger piston is internally provided with a valve hole. In the utility model, the piston and the buffering plunger piston are not coaxial, the partial grinding phenomenon between the piston and the buffering plunger piston caused by imprecision of the mechanical processing is prevented, thus simplifying the buffering design, i.e. omitting the accessories such as an adjustable flow valve, a check valve seat and the like. The buffering speed is controlled by the latus rectum of the buffering valve hole.

Description

A kind of buffering hydraulic cylinder

Technical field

The utility model relates to a kind of oil hydraulic cylinder, particularly a kind of buffering hydraulic cylinder.

Background technique

The big reduction of a fraction of buffering form of existing oil hydraulic cylinder is following several:

Gap buffer: when buffer plunger entered the cylinder end hole, the hydraulic oil in the hole was extruded from the annular space between plunger and hole wall, formed compensator or trimmer pressure.

Adjustable buffering: when buffer plunger enters the cylinder end hole, utilize the micro-gap between plunger and hole wall to form clearance seal, sealed way to cycle oil, force way to cycle oil to set up compensator or trimmer pressure by an adjustable restrictive valve.The cracking pressure of adjustable restrictive valve, the decision buffer speed is slow.

Variable restrictor buffering: when buffer plunger entered the cylinder end hole, oil circuit sealing, oil return went out via the restriction on the plunger (plunger axis is upwards opened triangle or semi-circular groove) concentrated flow and set up compensator or trimmer pressure.The area of restriction changes with the formation of plunger.

Shortcoming: need well to guarantee the piston of oil hydraulic cylinder and the coaxality of buffer plunger, bring certain difficulty to machining.If coaxality is bad, the inclined to one side phenomenon of the monolateral mill of piston and buffer plunger will take place, friction can cause tiny metal granule to be forced down for a long time, is scattering in the oil hydraulic cylinder, the potential safety hazard that has caused oil hydraulic cylinder to use.

Summary of the invention

The technical problems to be solved in the utility model is: a kind of buffering hydraulic cylinder of avoiding causing inadequately because of machining accuracy the monolateral inclined to one side phenomenon of mill of piston and buffer plunger is provided.

In order to solve the problems of the technologies described above, the utility model comprises piston rod, protecgulum, cylinder body, piston and bonnet, described piston is provided with the valve pocket that connects piston, be provided with movably long Buffer Unit in the valve pocket than valve pocket, Buffer Unit comprises buffer plunger and is fixed on two limit structures on the buffer plunger, buffer plunger cooperates with the middle lumen pore liquid sealing of valve pocket, be provided with valve opening in the buffer plunger, less than the ultimate range of the two-port of valve opening, two limit structures lay respectively at the outside of the two-port of valve opening to the length at the position that can cooperate with the buffer plunger liquid sealing on the valve pocket greater than the minimum range of the two-port of valve opening.

In order to make it simple in structure, easy to process and cushion effective, described valve pocket is a three stage structure, the aperture of the middle lumen pore of valve pocket is littler than the aperture of two ends lumen pore, described limit structure is the bolt that is fixed on the buffer plunger two ends, the nut of two bolts is arranged in the lumen pore at valve pocket two ends, and two nut thickness are less than the length of its residing lumen pore.

For the reliability of the liquid sealing that improves buffer plunger and valve pocket, the outer wall of described buffer plunger is provided with the multi-turn groove.Groove can cause the hydraulic lock effect, can guarantee the reliability that seals.

The beneficial effects of the utility model are: piston of the present utility model and buffering plunger are not coaxial settings, therefore can avoid causing the inclined to one side phenomenon of the monolateral mill of piston and buffer plunger inadequately because of machining accuracy.Also simplify Cushioning Design, for example removed annexes such as adjustable restrictive valve, unidirectional valve seat.The speed of buffer speed is by the latus rectum decision of buffering valve opening.

Description of drawings

Fig. 1 is the utility model structural representation; Fig. 2 is the partial enlarged drawing of Fig. 1; Fig. 3 piston of the present utility model home position structural representation; Structural representation when Fig. 4 is the firm setting in motion of piston; Fig. 5 is the structural representation of piston motion when touching protecgulum; Fig. 8 is the structural representation of piston during fully near protecgulum;

Among the figure: 1, piston rod, 2, protecgulum, 3, cylinder body, 4, piston, 5, Buffer Unit, 6, bonnet, 7, valve pocket, 8, buffer plunger, 9, groove, 10, valve opening, 11, port, 12, limit structure.

Embodiment

A kind of specific embodiment as shown in Figure 1, it comprises piston rod 1, protecgulum 2, cylinder body 3, piston 4, Buffer Unit 5 and bonnet 6.

As shown in Figure 2, piston 4 be provided with one with piston rod 1 axial identical perforation piston 43 stops valve pockets 7, the aperture of the middle lumen pore of valve pocket 7 is less than the aperture of two ends lumen pore, Buffer Unit 5 movably is arranged in the valve pocket 7, the total length of Buffer Unit 5 is longer than valve pocket 7, Buffer Unit 5 comprises buffer plunger 8 and is fixed on two limit structures 12 on the buffer plunger 8, and buffer plunger 8 cooperates with the middle lumen pore liquid sealing of valve pocket, and the outer wall of buffer plunger 8 is provided with multi-turn groove 9.Be provided with valve opening 10 in the buffer plunger 8, two port ones 1 of valve opening 10 are separately positioned on the sidewall at buffer plunger 8 two ends, the length of the middle lumen pore of valve pocket 7 greater than the minimum range of port one 1 less than the ultimate range of two-port 11, two limit structures 12 are two bolts, two bolts are threaded with buffer plunger 8 two ends respectively, the nut of two bolts is arranged in the lumen pore at valve pocket 7 two ends, and two nut thickness are less than the length of its residing lumen pore.

Working principle: as shown in Figure 3, at this moment, piston 4 is in the home position, piston 4 and buffering assembly 5 all withstand on the bonnet 6, valve opening 10 is by shutoff, piston 4 under the promotion of hydraulic oil to protecgulum 2 directions motions, hydraulic oil promote Buffer Unit 5 in piston 4 to left movement, make the right limit structure 12 of Buffer Unit 5 be against on the left side of lumen pores in the middle of the valve pocket 7 (as shown in Figure 4).Piston 4 and buffering assembly 5 continue motion under the promotion of hydraulic oil, Buffer Unit 5 is contact protecgulum 2 earlier, hydraulic oil promotes piston 4 and with Buffer Unit 5 relative movement takes place, as shown in Figure 5, when two port ones 1 of valve opening 10 all had part to expose the middle lumen pore of valve pocket 7, valve opening 10 just was communicated with the both sides of piston 4, the hydraulic oil of back cavity is under the effect of pressure, feed ante-chamber rapidly, the movement speed of oil hydraulic cylinder is just slow gets off, and plays the effect of buffering.Also push up (as shown in Figure 6) on the protecgulum 2 up to piston 4.

Claims

1. buffering hydraulic cylinder, comprise piston rod (1), protecgulum (2), cylinder body (3), piston (4) and bonnet (6), it is characterized in that: described piston (4) is provided with the valve pocket (7) that connects piston (4), be provided with movably long Buffer Unit (5) in the valve pocket (7) than valve pocket (7), Buffer Unit (5) comprises buffer plunger (8) and is fixed on last two limit structures of buffer plunger (8) (12), buffer plunger (8) cooperates with the middle lumen pore liquid sealing of valve pocket (7), be provided with valve opening (10) in the buffer plunger (8), less than the ultimate range of the two-port (11) of valve opening (10), two limit structures (12) lay respectively at the outside of the two-port of valve opening (10) to the length at the position that can cooperate with buffer plunger (8) liquid sealing on the valve pocket (7) greater than the minimum range of the two-port (11) of valve opening (10).

2. buffering hydraulic cylinder according to claim 1, it is characterized in that: described valve pocket (7) is a three stage structure, the aperture of the middle lumen pore of valve pocket (7) is littler than the aperture of two ends lumen pore, described limit structure (12) is for being fixed on the bolt at buffer plunger (8) two ends, the nut of two bolts is arranged in the lumen pore at valve pocket (7) two ends, and two nut thickness are less than the length of its residing lumen pore.

3. buffering hydraulic cylinder according to claim 1 and 2 is characterized in that: the outer wall of described buffer plunger (8) is provided with multi-turn groove (9).