CN201786790U

CN201786790U - Overflow valve for excavator

Info

Publication number: CN201786790U
Application number: CN201020503475XU
Authority: CN
Inventors: 曹东辉; 陈卫东; 陆爱华
Original assignee: Sany Heavy Machinery Ltd
Current assignee: Sany Heavy Machinery Ltd
Priority date: 2010-08-25
Filing date: 2010-08-25
Publication date: 2011-04-06
Anticipated expiration: 2020-08-25

Abstract

The utility model discloses an overflow valve for an excavator, which comprises a poppet head, a main spool, a main valve sleeve, a pilot spool, a pressure adjusting spring and a pilot valve sleeve, wherein the main spool is arranged in the main valve sleeve, the poppet head and the pilot valve sleeve are arranged in the main spool and the pilot spool is arranged in the pilot valve sleeve. The overflow valve is characterized in that the pilot valve sleeve is in a two-section split-type structure and consists of a valve body and a bonnet, the end of the valve body far away from the bonnet is arranged in the main spool, and the end of the valve body close to the bonnet is connected with the internal part of the main valve sleeve through a limiting structure. By dividing the pilot sleeve into the valve body and the bonnet, the length of the internal chamber of the pilot valve sleeve is reduced, the machining accuracy of the contact part between the pilot valve sleeve and the pilot spool is improved and the stability of the overflow valve is improved.

Description

A kind of excavator relief valve

Technical field

The utility model relates to a kind of valve body structure, is specifically related to a kind of excavator relief valve.

Background technique

In daily building was produced, excavator was a kind of engineering machinery commonly used, was widely used in occasions such as the foundation dredging of building construction and the cleaning after the completion, urban duct layings, construction of water conservancy works, had the advantage that construction is flexible, efficient is high.Excavator generally partly is made up of equipment, swivel gear, operator cabin, traveling gear and hydraulic control system etc.; wherein inevitably need use relief valve in hydraulic control system, relief valve mainly plays level pressure overflow effect and safety protection effect in hydraulic system.

The excavator relief valve is a pilot operated compound relief valve at present, referring to Figure 1 and Figure 2, mainly by lifting head 1, main valve plug 2, main valve housing 3, guide's spool 4, pressure adjusting spring 5 and guide's valve pocket 6 are formed, lifting head and main valve housing, pilot valve put all perforate, pressure oil damping hole from the lifting head enters in the main valve plug chamber, acts on guide's spool.When system pressure during less than the cracking pressure of guide's spool, pilot valve is in closed condition, and outside pressure equates in the main valve plug, because inside and outside area difference, main valve plug keeps closing under the effect of hydraulic coupling; When system pressure during greater than the cracking pressure of guide's spool, guide's spool is pushed open by pressure oil, pressure oil puts orifice flow oil sump tank on hole and the main valve housing by pilot valve, this moment since liquid stream fall by producing pressure during damping hole on the lifting head, make the main valve plug inside pressure greater than outer cavity pressure, the promotion main valve plug is opened, hydraulic oil orifice flow oil sump tank from the main valve housing, system pressure descends, when system pressure drops to cracking pressure less than guide's spool, guide's spool is closed, and outside pressure difference hour in the main valve plug is at effect ShiShimonoseki make and break mouth of Returnning spring.

Yet in the use of reality, find, when above-mentioned relief valve uses, guide's spool needs frequent the keying, the start-stop performance of pilot valve has determined the performance of this relief valve, therefore the part that contacts with guide's spool tapering on guide's valve pocket endoporus is extremely important, for guaranteeing the stable of relief valve performance, guide's valve pocket should the often exigent machining precision in zone, and this guide's valve pocket endoporus is longer, should process and detect and all compare difficulty in the zone in guide's valve pocket, machining accuracy is difficult to be guaranteed, and causes the pilot valve performance effectively not guaranteed, the stability of relief valve is a greater impact, in addition, coaxality mainly relies on the screw thread of guide's valve pocket to locate to guarantee between main valve plug and the main valve housing, because guide's valve pocket is longer, the little deviation of screw thread location also can influence the cooperation of main valve plug and main valve housing, causes sealing bad generation and leaks.

Summary of the invention

The utility model purpose provides a kind of excavator relief valve, by the improvement to structure, has reduced guide's valve pocket length in the relief valve, has improved guide's valve pocket machining accuracy, has improved the stability of relief valve.

For achieving the above object, the technical solution adopted in the utility model is: a kind of excavator relief valve, comprise lifting head, main valve plug, main valve housing, guide's spool, pressure adjusting spring and guide's valve pocket, described main valve plug is arranged at main valve housing inside, described main valve plug inside is provided with lifting head and guide's valve pocket, described guide's valve pocket inside is provided with guide's spool, described guide's valve pocket is two-section separated structure, constitute by a valve body and a valve gap, described valve body is arranged at main valve plug inside away from valve gap one end, and nearly valve gap one end of described valve body is connected through limit structure and main valve housing inside.

In the technique scheme, described relief valve is a prior art, adopt pilot operated compound relief valve, mainly by lifting head, main valve plug, main valve housing, guide's spool, pressure adjusting spring and guide's valve pocket are formed, lifting head and main valve housing, pilot valve put all perforate, and pressure oil damping hole from the lifting head enters in the main valve plug chamber, acts on guide's spool.In this structure, guide's valve pocket is two-section separated structure, comprise a valve body and a valve gap, guide's spool is arranged at body cavity, because guide's valve pocket is divided into valve body and two parts of valve gap, thereby shortened the length of guide's valve pocket greatly, reduced the length of guide's valve pocket inner chamber, make that the processing of guide's valve pocket inner chamber and guide's spool contact segment is more convenient, improved machining accuracy, and valve body one end is arranged at main valve plug inside, the other end carries out spacing the connection through limit structure with main valve housing, improves the quality of fit between main valve plug and the main valve housing.

Further technological scheme, nearly valve gap one end of described valve body is outwards routed up the formation boss, is engaged in described main valve housing inboard with described boss and offers groove, and both engage the described limit structure of spacing formation.The described valve body one end formation boss that turns up is engaged in the main valve housing inboard with boss and offers groove, and is concavo-convex spacing between valve body and the main valve housing, is used for axially reaching the radial location valve body, thereby improves the quality of fit of main valve plug and main valve housing.

Because the technique scheme utilization, the advantage that the utility model compared with prior art has is:

1, since the utility model by guide's valve pocket being divided into valve body and valve gap two-part, guide's spool is arranged at valve inner, reduced guide's valve pocket inner chamber length, make guide's valve pocket inner chamber and guide's spool contact segment be convenient to processing, improve machining accuracy, and then improved the stability of relief valve;

2, valve body one end of guide's valve pocket is arranged at main valve plug inside in the utility model, and the other end is connected with main valve housing through limit structure, has improved the quality of fit between main valve plug and the main valve housing;

3, the utility model need not change on a large scale to existing structure of relief valve, is easy to realize;

4, the utility model is simple in structure, and is easy to use, and easily manufactured, is fit to promote the use of.

Description of drawings

Fig. 1 is a structure of relief valve schematic representation in the prior art;

Fig. 2 is a pilot valve nested structure schematic representation among Fig. 1;

Fig. 3 is the utility model embodiment one a structural representation.

Wherein: 1, lifting head; 2, main valve plug; 3, main valve housing; 4, guide's spool; 5, pressure adjusting spring; 6, guide's valve pocket; 11, lifting head; 12, main valve plug; 13, main valve housing, 14, guide's spool; 15, pressure adjusting spring; 16, valve body; 17, valve gap; 18, boss.

Embodiment

Below in conjunction with drawings and Examples the utility model is further described:

Embodiment one: referring to shown in Figure 3, a kind of excavator relief valve, comprise lifting head 11, main valve plug 12, main valve housing 13, guide's spool 14, pressure adjusting spring 15 and guide's valve pocket, described main valve plug 12 is arranged at main valve housing 13 inside, described main valve plug 12 inside are provided with lifting head 11 and guide's valve pocket, described guide's valve pocket inside is provided with guide's spool 14, described guide's valve pocket is two-section separated structure, constitute by a valve body 16 and a valve gap 17, described valve body is arranged at main valve plug inside away from valve gap one end, nearly valve gap one end of described valve body is outwards routed up and is constituted boss 18, be engaged in described main valve housing inboard with described boss and offer groove, both engage the described limit structure of spacing formation.

This structure in use, because with guide's valve pocket separated into two parts: valve body 16 and valve gap 17, offer groove in main valve housing 13, valve body is provided with boss 18, is used for radially reaching axial restraint valve body 16, main valve plug, lifting head are set in turn in main valve housing inside, at first valve body is put into the main valve plug inner chamber during installation, it is radially spacing to rely on the main valve housing upper groove that valve body is axially reached, and is screwed into valve gap in the main valve housing then and compresses valve body, thereby valve body is fixed, can normally be used relief valve then.

Claims

1. excavator relief valve, comprise lifting head (11), main valve plug (12), main valve housing (13), guide's spool (14), pressure adjusting spring (15) and guide's valve pocket, described main valve plug (12) is arranged at main valve housing (13) inside, described main valve plug (12) inside is provided with lifting head (11) and guide's valve pocket, described guide's valve pocket inside is provided with guide's spool (14), it is characterized in that: described guide's valve pocket is two-section separated structure, constitute by a valve body (16) and a valve gap (17), described valve body (16) is arranged at main valve plug (12) inside away from valve gap (17) one ends, and nearly valve gap (17) one ends of described valve body (16) are connected through limit structure and main valve housing (13) inside.

2. a kind of excavator relief valve according to claim 1, it is characterized in that: nearly valve gap (17) one ends of described valve body (16) are outwards routed up and are constituted boss (18), be engaged in described main valve housing (13) inboard with described boss and offer groove, both engage the described limit structure of spacing formation.