CN203655787U

CN203655787U - Travel limiting valve for dumper

Info

Publication number: CN203655787U
Application number: CN201420042632.XU
Authority: CN
Inventors: 李学军; 郑建国
Original assignee: SHIYAN PENGZE CAR COMPONENT Co Ltd
Current assignee: SHIYAN PENGZE CAR COMPONENT Co Ltd
Priority date: 2014-01-23
Filing date: 2014-01-23
Publication date: 2014-06-18
Anticipated expiration: 2024-01-23

Abstract

The utility model discloses a travel limiting valve for a dumper. The inner cavity of a valve body is partitioned into a valve rod moving cavity and an air distribution cavity through a step hole, a choke plug is arranged at the port of the air distribution cavity, a second reset spring is arranged between the choke plug and the valve core, and the valve core sticks close to the step hole. A working port in the valve body is communicated with the back end of the valve rod moving cavity, the air inlet in the valve body is communicated with the air distribution cavity, an emptying port in the valve body is communicated with the outer ring channel of the valve core, an air guide hole is formed in the center of the valve core, and the back end of the valve rod moving cavity is communicated with the air distribution cavity. A sealing gasket is arranged on the end face of the inner end of the valve rod. When a valve rod moves inwards, the sealing gasket can block the air guide hole by passing through the step hole, the valve core can be driven to move, and the emptying port is communicated with the back end of the valve rod moving cavity through the outer ring channel of the valve core. The structure of the valve body is changed, and reliable end face sealing is adopted, thereby effectively prolonging the service life of a sealing element, and improving the sealing performance. Moreover, the limiting valve is simple in structure, and the machining accuracy is ensured easily. Meanwhile, an assembly process is simpler.

Description

Dumping car stroke position limiting valve

Technical field

The utility model relates to a kind of and matching used stroke position limiting valve of vehicle lifter HYDRAULIC CONTROL SYSTEM.

Background technique

At present, engineering dump truck is widely used plunger cylinder by the flexible lifting decline that realizes the large case of vehicle of Pneumatic reversal valve control oil cylinder on the market, due to the working principle restriction of plunger case, in the time that plunger case is stretched over the limit, must have a control mechanism to cut off oil circuit makes oil hydraulic cylinder stop stretching with erosion control cylinder, play the effect of safety protection, conventional is by stroke collision block compression limited valve valve rod in the market, thereby die and realize working connection break-make and control the work of oil hydraulic cylinder by air drain switching gas circuit break-make control Pneumatic reversal valve control cylinder on valve rod, its structure is shown in Fig. 1, the critical piece of stroke position limiting valve is valve body 4, valve rod 1, spacer ring 9, seal ring 8, reseting spring device, the medium position of valve body 4 is provided with stop collar 2, valve body 4 is divided into valve pocket and installation cavity, valve pocket one end of valve body 4 is provided with suction port P, working hole A, evacuation port T, reseting spring device is arranged in the installation cavity of valve body 4, reseting spring device is by the spring seat 3 of valve rod 1 tail end, Returnning spring 6, plug 7 forms, stop collar 2 is located by lining 5 and the plug 7 of valve body 4, when oil hydraulic cylinder rises to while being about to approach limit position, the valve rod 1 of stroke collision block compression limited valve moves right, by the gas booking groove on valve rod 1 be arranged on spacer ring 6 in valve body 4 and gas distribution channels that seal ring 7 forms, working hole A and suction port P are disconnected, thereby cut-out air supply channel, air in cylinder is discharged by evacuation port T, valve rod 1 resets under reseting spring device effect, control oil cylinder quits work and plays safe spacing effect, this structure has two large defects, the one, seal ring need to slide when distribution stair working on valve rod, easily cause seal ring breakage and make the bad operational failure that causes of the too fast sealing effect of ring wear, greatly reduce the working life of safe limit valve, the 2nd, due to complex structure manufacture processing and assembling difficulty.

Summary of the invention

In order to overcome the structure that existing dumping car stroke position limiting valve is ring packing and gas distribution channels, easily cause seal ring breakage to cause the bad problem of sealing effect, the utility model proposes dumping car stroke position limiting valve, by changing distribution device, eliminate the slided phenomenon of seal ring of valve rod gas booking groove, seal completely reliably the working life of prolongation limited valve and improve functional reliability by end face seal form.

For this reason, the technical solution of the utility model is: dumping car stroke position limiting valve, comprise valve body, valve rod, spool, body cavity is divided into valve rod mobile cavity by step hole, air distribution cavity, valve rod coordinates with the slipper seal of valve rod mobile cavity, stretch out from valve rod mobile cavity the outer end of valve rod, be provided with dust-proof seal ring and guide sleeve at the oral area of valve rod mobile cavity, the inner of valve rod is provided with connection axle journal, between the connection axle journal of valve rod and step hole, be provided with the first Returnning spring, it is characterized in that: spool is placed in air distribution cavity, spool coordinates with air distribution cavity slipper seal, the oral area of air distribution cavity is provided with plug, between plug and spool, be provided with the second Returnning spring, make to be close to step hole, between spool and the end face of step hole, seal by 0 shape seal ring, working hole on valve body is communicated with the rear end of valve rod mobile cavity, and the suction port on valve body is communicated with air distribution cavity, the evacuation port on valve body and spool outer ring channel connection, and the center of spool is provided with gas port, and the rear end of valve rod mobile cavity is communicated with air distribution cavity, the inner end face of valve rod is provided with sealing gasket, and in the time that valve rod moves inward, sealing gasket can pass step hole shutoff gas port, can promote spool and move, and makes evacuation port pass through spool outer ring passage and is communicated with the rear end of valve rod mobile cavity.

Beneficial effect: by changing valve body structure, change original circumferential slipper seal into reliable end face seal, because sealing gasket and valve rod do not produce relative sliding, thereby effectively improved working life and the sealability of Sealing; And this limited valve is simple in structure, machining accuracy more easily guarantees, makes assembly technology also more simple simultaneously.

Accompanying drawing explanation

Fig. 1 is the structural drawing of existing dumping car stroke position limiting valve.

Fig. 2 is the structural drawing of the utility model dumping car stroke position limiting valve.

Embodiment

Dumping car stroke position limiting valve as shown in Figure 2, comprise valve body 19, valve rod 10, spool 20, body cavity is divided into valve rod mobile cavity by step hole, air distribution cavity, valve rod 10 coordinates (realizing sealing by the first seal ring 14) with the slipper seal of valve rod mobile cavity, stretch out from valve rod mobile cavity the outer end of valve rod, be provided with dust-proof seal ring 11 and guide sleeve 13(guide sleeve is located by elastic collar 12 at the oral area of valve rod mobile cavity), the inner of valve rod is provided with connection axle journal, between the connection axle journal of valve rod and step hole, be provided with the first Returnning spring 15, spool 20 is placed in air distribution cavity, spool 20 coordinates the oral area of air distribution cavity in (realizing sealing by the second seal ring 18) to be provided with plug 22 with air distribution cavity slipper seal, between plug 22 and spool 20, be provided with the second Returnning spring 21, make spool 20 be close to step hole, between spool and the end face of step hole, seal 17 by 0 shape seal ring, working hole A on valve body is communicated with the rear end of valve rod mobile cavity, and the suction port P on valve body is communicated with air distribution cavity, the evacuation port T on valve body and spool outer ring channel connection, and the center of spool is provided with gas port, and the rear end of valve rod mobile cavity is communicated with air distribution cavity, the inner end face of valve rod is provided with sealing gasket 16, and in the time that valve rod moves inward, sealing gasket 16 can pass step hole shutoff gas port, can promote spool 20 and move, and makes evacuation port pass through spool outer ring passage and is communicated with the rear end of valve rod mobile cavity.

The utility model innovation is:

By changing valve body and valve core structure, when being stretched over while approaching limit position, oil cylinder moves right by stroke collision block compression valve rod 10, first the sealing gasket of valve rod the inner contacts spool left end and now gas-entered passageway is disconnected, now because the air pressure in selector valve cylinder is not taken, valve core of main valve does not reset, oil hydraulic cylinder continues to rise, thereby the further compression valve rod of stroke collision block making moves to right and promotes spool 20 and continue to move right and open emptying passage, air pressure in selector valve control cylinder is emptying rapidly, valve core of main valve resets and disconnects oil circuit and oil hydraulic cylinder is quit work play safe spacing effect under the effect of Returnning spring.

Claims

1. dumping car stroke position limiting valve, comprise valve body, valve rod, spool, body cavity is divided into valve rod mobile cavity by step hole, air distribution cavity, valve rod coordinates with the slipper seal of valve rod mobile cavity, stretch out from valve rod mobile cavity the outer end of valve rod, be provided with dust-proof seal ring and guide sleeve at the oral area of valve rod mobile cavity, the inner of valve rod is provided with connection axle journal, between the connection axle journal of valve rod and step hole, be provided with the first Returnning spring, it is characterized in that: spool is placed in air distribution cavity, spool coordinates with air distribution cavity slipper seal, the oral area of air distribution cavity is provided with plug, between plug and spool, be provided with the second Returnning spring, make spool be close to step hole, working hole on valve body is communicated with the rear end of valve rod mobile cavity, and the suction port on valve body is communicated with air distribution cavity, the evacuation port on valve body and spool outer ring channel connection, and the center of spool is provided with gas port, and the rear end of valve rod mobile cavity is communicated with air distribution cavity, the inner end face of valve rod is provided with sealing gasket, and in the time that valve rod moves inward, sealing gasket can pass step hole shutoff gas port, can promote spool and move, and makes evacuation port pass through spool outer ring passage and is communicated with the rear end of valve rod mobile cavity.