CN201496527U

CN201496527U - Combined piston ring with load-off grooves

Info

Publication number: CN201496527U
Application number: CN2009201936723U
Authority: CN
Inventors: 胡泽华; 范清
Original assignee: Guangzhou Mechanical Engineering Research Institute Co Ltd
Current assignee: Guangzhou Mechanical Engineering Research Institute Co Ltd
Priority date: 2009-08-28
Filing date: 2009-08-28
Publication date: 2010-06-02
Anticipated expiration: 2019-08-28

Abstract

The utility model discloses a combined piston ring with load-off grooves, which comprises a large piston ring and a small piston ring pinched at the periphery of the large piston ring, the large piston ring and the small piston ring are respectively provided with two notches which are mutually staggered, and the large piston ring and the small piston ring are positioned through a positioning pin; and a plurality of load-off grooves are formed on the outer circumference of the large piston ring, and a plurality of load-off holes are formed in the radial direction of the large piston ring and lead to the load-off grooves. The compound piston ring with the load-off grooves has the advantages of good sealing performance and long service life.

Description

The compound piston ring of band compensating groove

Technical field

The utility model relates to the piston ring of the reciprocal non-lubricated compressor that compresses pressurized gas, is specifically related to a kind of compound piston ring with compensating groove.

Background technique

Surpass the piston compressor of 5MPa for exhaust pressure, during gap between sealing cylinder and piston ring, the structure of conventional piston ring is taked following several form of cut or cuts:

1, straight cut shown in Figure 1;

2, angular cut shown in Figure 2;

3, overlap joint mouth shown in Figure 3.

Adopt the form of straight cut or angular cut, gas is very easy to produce by otch and leaks, so piston ring is usually designed to several roads, and however, collaborating between cylinder and the bent axle (leakage) still exists, thereby reduced the working efficiency of compressor.

Although the piston ring sealing effect of overlap joint degree of lip-rounding formula is better slightly than straight cut or angular cut form, also there is the problem that can not seal fully.The piston ring of overlap joint degree of lip-rounding formula will reach the effect of sealing fully, must guarantee two conditions simultaneously:

1, the right side C (see figure 3) of piston ring must be fitted fully with the right flank of piston channel;

2, the overlap joint mouth faying surface A and the B of piston ring must fit fully.

Overlap joint mouthful faying surface A and B generally process by milling, and the precision of milling processing is to be difficult to guarantee that A and B can also fit fully under the situation that C face and piston channel are fitted fully.When t1＞t2, A face and B face are fitted fully, thereby make the C face produce warpage, C face injustice; When t1＜t2, gapped between A face and the B face, even under the pressure effect of pressurized gas, the A face can not overlap fully with the B face, and this is the same for its gas leakage situation and angular cut cyclic group; Have only when t1 and t2 size and tolerance are in full accord, could really reach the effect of sealing fully, and this chance is very little.

Even more serious is, because lap-joint's axial width dimension is the straight cut of routine or half of angular cut form, so the strength of materials is relatively poor, under the effect of high-pressure gas pressure, lap-joint is very easy to take place the situation of fracture, has a strong impact on the working life of piston ring.

In addition, no matter select the piston ring of above which kind of structure, owing to there is very big pressure difference between piston ring endoporus and the cylindrical, cause the piston ring endoporus in entire work process, to have bigger radial force effect all the time, the intensity of plastic hoop itself has certain reduction under the high temperature, therefore finally causes obviously reduce the working life of piston ring.

This shows, solve reciprocal Piston Rings for Non-lubricated Compressors working life and sealability, is the difficult problem that reciprocal non-lubricated compressor needs to be resolved hurrily.

The model utility content

The utility model provides the compound piston ring of the band compensating groove of a kind of good seal performance, long service life in order to overcome the deficiency that above prior art exists.

The purpose of this utility model realizes by following technological scheme: the compound piston ring of this band compensating groove, it is characterized in that: comprise big piston ring and hoop small piston ring in big piston ring periphery, described big piston ring and small piston ring all have otch, two otch stagger mutually, locate with locating stud between big piston ring, the small piston ring, have several compensating grooves on the excircle of big piston ring, the big piston ring radially has several unloading holes, and unloading hole leads to compensating groove.

As a kind of preferred version, described locating stud is the real core or the elastic cylindrical pin of metal or plastics.

As a kind of preferred version, the sectional shape of described big piston ring is L shaped.

As a kind of preferred version, the sectional shape of described small piston ring is a rectangle.

As a kind of preferred version, the angle that described two otch stagger mutually is 30 °～180 °.

According to actual needs, described two otch are straight cut or angular cut.

As a kind of preferred version, evenly have 4 compensating grooves on the excircle of described big piston ring, the big piston ring radially evenly has 8 unloading holes, and per 2 unloading holes lead to 1 compensating groove.

According to actual needs, the sectional shape of described compensating groove is V-arrangement, U-shaped, semicircle, rectangle or trapezoidal, and unloading hole is a circular hole.

The utility model has following advantage with respect to prior art:

One, the compound piston ring of this band compensating groove with the locating stud location, guarantees that two otch stagger mutually between big piston ring, the small piston ring, and gas is considerably less by the face leakage amount of piston ring, good sealing effect.Because the hole axle cooperates and the end face cooperation all is to guarantee quality of fit by Vehicle Processing, therefore, no matter be that otch 4 by the small piston ring is through excessive, the seal face of small piston ring (seal face 11 of Fig. 5) flows into the gas leakage of otch 3 formation of big piston ring, still by big, (Fig. 5's is big for the fitting surface of small piston ring, the fitting surface 10 of small piston ring) through excessive, the gas leakage that the otch 3 of the seal face of small piston ring (seal face 11 of Fig. 5) inflow big piston ring forms all can be considerably less, unique passage Lou of unloading is a local small leakage along the L shaped direction of the otch of big piston ring, thereby reaches the better seal effect.

Two, have several compensating grooves on the excircle of big piston ring, the big piston ring radially has several unloading holes, unloading hole leads to compensating groove, unloading hole is guided to the on high-tension side pressed gas of piston ring endoporus the compensating groove of piston ring working surface, effectively improve the pressure distribution of piston ring working surface, reduce the working pressure on piston ring surface, prolonged the working life of piston ring, for the high voltage oil-free lubricate compressors provides a kind of reliable piston sealing structure.Through the test data rough estimates, when exhaust pressure is 4MPa, the compound piston ring of this band compensating groove, air leakage reduces more than 70% than the piston ring of angular cut form, compare with the piston ring of overlap joint degree of lip-rounding formula, though the air leakage of the utility model piston ring is more about 20% than increasing, its life-span has improved more than 80%.

Three, this piston ring can be used for explosive motor and piston gas compressor, and this piston ring structure has good operability and reliability, and is easy for installation.

Description of drawings

Fig. 1 is the structural representation of conventional straight cut piston ring.

Fig. 2 is the structural representation of conventional diagonal cut joint piston ring.

Fig. 3 is the structural representation of conventional overlap joint gap piston ring.

Fig. 4 is the front view of a kind of compound piston ring with compensating groove of the utility model.

Fig. 5 is the A-A sectional view of Fig. 4.

Fig. 6 is the front view of big piston ring of the piston ring of Fig. 4.

Fig. 7 is the B-B sectional view of Fig. 6.

Fig. 8 is the mounting point schematic representation of piston ring in cylinder of Fig. 4.

Embodiment

The utility model is described in further detail below in conjunction with drawings and Examples.

A kind of compound piston ring as shown in Figure 4 with compensating groove, comprise big piston ring 1 and hoop small piston ring 2 in big piston ring 1 periphery, big piston ring 1 and small piston ring 2 have

otch

3,4, two

otch

3,4 stagger mutually, the angle that two

otch

3,4 stagger mutually is 180 °, with locating stud 5 location, locating stud 5 is the elastic cylindrical pin of metal or plastics between big piston ring 1, the small piston ring 2.

According to actual needs, two

otch

3,4 are straight cut or angular cut.

As shown in Figure 5, the sectional shape of big piston ring 1 is L shaped, and the sectional shape of small piston ring 2 is a rectangle.

As shown in Figure 6, evenly have 4 compensating grooves 6 on the excircle of big piston ring 1, big piston ring 1 radially evenly has 8 unloading holes 7, and per 2 unloading holes 7 lead to 1 compensating groove 6.

As shown in Figure 7, the sectional shape of compensating groove 6 is semicircle, and unloading hole 7 is a circular hole.

As shown in Figure 8, piston ring after the combination is installed in the annular groove between cylinder 8 and the piston 9, open four compensating grooves 6 on the working surface of small piston ring 2, simultaneously open two unloading holes 7 at each compensating groove 6 corresponding position, pressurized gas are introduced the cylindrical working surface by endoporus, improve the pressure distribution of piston ring working surface effectively, reduce the working pressure on piston ring surface, prolonged the working life of piston ring.

Above-mentioned embodiment is a preferred embodiment of the present utility model; can not limit claim of the present utility model; other any change that does not deviate from the technical solution of the utility model and made or other equivalent substitute mode are included within the protection domain of the present utility model.

Claims

1. be with the compound piston ring of compensating groove, it is characterized in that: comprise big piston ring and hoop small piston ring in big piston ring periphery, described big piston ring and small piston ring all have otch, two otch stagger mutually, locate with locating stud between big piston ring, the small piston ring, have several compensating grooves on the excircle of big piston ring, the big piston ring radially has several unloading holes, and unloading hole leads to compensating groove.

2. the compound piston ring of band compensating groove according to claim 1 is characterized in that: described locating stud is the real core or the elastic cylindrical pin of metal or plastics.

3. the compound piston ring of band compensating groove according to claim 1 is characterized in that: the sectional shape of described big piston ring is L shaped.

4. the compound piston ring of band compensating groove according to claim 3 is characterized in that: the sectional shape of described small piston ring is a rectangle.

5. the compound piston ring of band compensating groove according to claim 1 is characterized in that: the angle that described two otch stagger mutually is 30 °～180 °.

6. the compound piston ring of band compensating groove according to claim 1 is characterized in that: described two otch are straight cut or angular cut.

7. according to the compound piston ring of each described band compensating groove of claim 1～6, it is characterized in that: evenly have 4 compensating grooves on the excircle of described big piston ring, the big piston ring radially evenly has 8 unloading holes, and per 2 unloading holes lead to 1 compensating groove.

8. the compound piston ring of band compensating groove according to claim 7 is characterized in that: the sectional shape of described compensating groove is V-arrangement, U-shaped, semicircle, rectangle or trapezoidal, and unloading hole is a circular hole.