CN209146036U - A piston assembly for a hydraulic cylinder - Google Patents

Abstract

The utility model relates to a kind of piston assemblies for hydraulic cylinder.Its technical solution is: the piston assembly is made of support ring (1), seal ring assembly (2), sealing ring (3) and piston (4).Seal groove (6) are provided at the center of two supports annular groove (5) of piston (4), the bottom of seal groove (6) is equipped with sealing ring (3), and the outer wall for being close to sealing ring (3) is set with seal ring assembly (2).Seal ring assembly (2) is the complete circular ring shape being made of sealing ring (7) and rubber pad (8), the outer wall of sealing ring (7) is equably provided with big-diameter blind hole, big-diameter blind hole is located on the center line of sealing ring (7), passes through the big-diameter blind hole hole heart and with sealing ring (7) center line in positive 45 ° and in having 2 small blind holes on minus 45 ° of directions；Sealing ring (3) is annulus breakaway-element.The utility model has the characteristics that small frictional force, high frequency sound, can bear high pressure, good seal performance, long working life, energy adjust automatically seal clearance and convenient for disassembly and assembly, the hydraulic cylinder suitable for high pressure low friction.

Description

A piston assembly for a hydraulic cylinder

technical field

The utility model belongs to the technical field of pistons of hydraulic cylinders. In particular, it relates to a piston assembly for a hydraulic cylinder.

Background technique

At present, in some hydraulic cylinders, a constant gap seal is used to reduce friction, but this seal cannot completely prevent leakage due to the existence of gaps. Therefore, the sealing performance is poor. In addition, this kind of seal has higher requirements on the geometric shape and surface machining accuracy of the parts, and cannot be automatically compensated after wear.

It is sealed with Gree ring, which must be manufactured in strict accordance with the size requirements of the hydraulic cylinder, and its elasticity is small and the installation is difficult. When the seal is worn, it is difficult to compensate for the worn sealing gap. If the fit is too tight, the seal and the inner wall of the cylinder will The destruction of the oil film will increase the friction, and the general structure is difficult to ensure the lubrication performance of the sealing gap.

SUMMARY OF THE INVENTION

The utility model aims to overcome the above-mentioned technical defects, and the purpose is to provide a hydraulic cylinder with small friction force, high frequency response, high pressure resistance, good sealing performance, long working life, automatic adjustment of sealing gap and convenient disassembly and assembly. Piston assembly.

In order to achieve the above purpose, the technical scheme adopted by the present invention is that the piston assembly of the hydraulic cylinder is composed of a support ring, a sealing ring assembly, a sealing ring and a piston.

Support ring grooves are symmetrically opened on the cylindrical surface of the piston near both sides, and support rings are respectively installed in the two support ring grooves; the width of the support ring groove is the same as that of the support ring, and the depth of the support ring groove is the same as that of the support ring. Same thickness.

There is a sealing groove at the center of the two supporting ring grooves of the piston, a sealing ring is installed at the bottom of the sealing groove, and a sealing ring assembly is fitted close to the outer wall of the sealing ring; the width of the sealing groove is related to the width of the sealing ring and the sealing ring assembly. are the same width, and the depth of the sealing groove is the sum of the thickness of the sealing ring and the thickness of the sealing ring assembly.

The sealing ring assembly is a complete circular ring composed of a sealing ring and a rubber gasket. The arc length of the rubber gasket is 0.005 to 0.01 times that of the complete ring; same.

One end of the sealing ring connected with the rubber gasket is a concave curved surface, and the other end is a convex curved surface. The radius of curvature is 0.5 to 0.55 times the width of the sealing ring; one end of the rubber pad connected with the sealing ring is the corresponding convex curved surface, and the other end is the corresponding concave curved surface. The intersection lines of the outer walls of the pads are all arc-shaped, and the arc-shaped curvature radii at both ends of the rubber pad are 0.5 to 0.55 times the width of the rubber pad.

Large blind holes are evenly opened on the outer wall of the sealing ring, the large blind holes are located on the center line of the sealing ring, and the spacing of the large blind holes is 3.5 to 4 times the width of the sealing ring; Two small blind holes are respectively opened in the direction of positive 45° and negative 45° of the center line, and the distance between each small blind hole and the adjacent small blind holes is 0.6 to 0.7 times of the width of the sealing ring.

The sealing ring is a ring break type, one end of the break is a concave curved surface, and the other end is a convex curved surface. The arc curvature radius at both ends of the ring is 0.5 to 0.55 times the width of the sealing ring; the two sides of the sealing ring are symmetrical annular concave curved surfaces; the cross section of the annular concave curved surface is arc-shaped, and the The radius of curvature of the arc is 0.5 to 0.55 times the thickness of the sealing ring.

The thickness of the sealing ring is 0.5-0.6 times the depth of the sealing groove, and the material of the sealing ring is aluminum bronze alloy material.

The thickness of the sealing ring is 0.4 to 0.5 times the depth of the sealing groove; the material of the sealing ring is fluorine rubber.

The material of the rubber pad is fluorine rubber.

The diameter of the large blind hole is 0.15-0.2 times the width of the sealing ring, and the depth of the large blind hole is 0.16-0.18 times the thickness of the sealing ring.

The diameter of the small blind hole is 0.1-0.15 times the width of the sealing ring, and the depth of the small blind hole is 0.1-0.15 times the thickness of the sealing ring.

Owing to adopting the above-mentioned technical scheme, the utility model has the following advantages compared with the prior art:

(1) The utility model processes multiple groups of blind holes on the outer wall of the sealing ring. Each group of blind holes is composed of four small blind holes and one large blind hole. Hydraulic oil is stored in each group of blind holes. When the piston moves, The hydraulic oil in the blind hole is taken out, and an oil film is automatically formed in the gap between the piston and the inner wall of the cylinder, which reduces friction and improves lubrication and sealing performance.

(2) The utility model is provided with concave curved surfaces on both sides of the sealing ring. Under the action of high pressure oil, its lips are opened outward. can also enhance the sealing performance.

(3) The utility model is equipped with a rubber pad at the fracture of the sealing ring, which can not only prevent the leakage of high-pressure oil from the circular fracture, but also facilitate disassembly and assembly.

(4) The material of the sealing ring of the present utility model is aluminum bronze alloy with certain elastic deformation, and the friction coefficient is small, which can speed up the response frequency of the hydraulic cylinder. It can expand freely to compensate for the gap that is slightly worn, improve the working life of the sealing ring, and automatically adjust the sealing gap to prevent leakage.

Therefore, the utility model has the characteristics of low friction force, high frequency response, high pressure resistance, good sealing performance, long working life, automatic adjustment of sealing gap and convenient disassembly and assembly, and is suitable for hydraulic cylinders with high pressure and low friction.

Description of drawings

Fig. 1 is a kind of structural representation of the utility model;

Fig. 2 is the structural representation of piston 4 in Fig. 1;

Fig. 3 is the partial enlarged schematic diagram of I in Fig. 1;

FIG. 4 is a schematic structural diagram of the sealing ring assembly 2 in FIG. 1;

Fig. 5 is the expanded schematic diagram of the sealing ring assembly 2 in Fig. 3;

Fig. 6 is the A-A view schematic diagram in Fig. 5;

Fig. 7 is the B-B view schematic diagram in Fig. 5;

Fig. 8 is the shape schematic diagram of the sealing ring 3 in Fig. 1;

Fig. 9 is the expanded schematic diagram of the sealing ring 3 in Fig. 3;

FIG. 10 is a schematic view from the direction C-C in FIG. 9 .

Detailed ways

The present utility model will be further described below with reference to the accompanying drawings and specific embodiments, which are not intended to limit its protection scope.

Example 1

A piston assembly for a hydraulic cylinder. The piston assembly of the hydraulic cylinder consists of a support ring 1 , a sealing ring assembly 2 , a sealing ring 3 and a piston 4 .

As shown in Figures 1 and 2, support ring grooves 5 are symmetrically opened on the cylindrical surface of the piston 4 near both sides, and the two support ring grooves 5 are respectively equipped with support rings 1; The width of the ring 1 is the same, and the depth of the support ring groove 5 is the same as the thickness of the support ring 1 .

As shown in FIGS. 1 to 3 , a sealing groove 6 is opened at the center of the two support ring grooves 5 of the piston 4 , the bottom of the sealing groove 6 is equipped with a sealing ring 3 , and the outer wall of the sealing ring 3 is fitted with a sealing ring Assembly 2; the width of the sealing groove 6 is the same as the width of the sealing ring 3 and the width of the sealing ring assembly 2, and the depth of the sealing groove 6 is the sum of the thickness of the sealing ring 3 and the thickness of the sealing ring assembly 2.

As shown in FIG. 4 , the sealing ring assembly 2 is a complete annular ring composed of a sealing ring 7 and a rubber gasket 8, and the arc length of the rubber gasket 8 is 0.005 to 0.008 times that of the complete ring; the cross section of the sealing ring 7 is Rectangular, the section of the rubber gasket 8 is the same as that of the sealing ring 7 .

As shown in FIG. 5 , one end of the sealing ring 7 connected with the rubber pad 8 is a concave curved surface, and the other end is a convex curved surface. The intersections of the concave and convex curved surfaces of the sealing ring 7 and the outer wall of the sealing ring 7 are all It is arc-shaped, and the arc-shaped curvature radius at both ends of the sealing ring 7 is 0.5 to 0.55 times the width of the sealing ring 7; one end of the rubber pad 8 connected with the sealing ring 7 is a corresponding convex curved surface, and the other end is a corresponding concave shape Curved surfaces, the intersections of the concave and convex curved surfaces of the rubber pad 8 and the outer wall of the rubber pad 8 are all arcs, and the arc curvature radii at both ends of the rubber pad 8 are 0.5-0.55 times the width of the rubber pad 8 .

As shown in FIGS. 5 and 6 , large blind holes are evenly opened on the outer wall of the sealing ring 7 , the large blind holes are located on the center line of the sealing ring 7 , and the spacing between the large blind holes is 3.5 to 4 times the width of the sealing ring 7 . ; As shown in Figure 5 and Figure 7, through the center of the large blind hole and the center line of the sealing ring 7 is at a positive 45° and a negative 45° direction, respectively, there are 2 small blind holes, each small blind hole and phase. The distance between adjacent small blind holes is 0.6 to 0.65 times the width of the sealing ring 7 .

As shown in Figure 8, the sealing ring 3 is a ring-shaped disconnected type; as shown in Figure 9, one end of the disconnection is a concave curved surface, and the other end is a convex curved surface. The concave curved surface and the convex curved surface of the sealing ring 3 The intersection lines with the outer wall of the sealing ring 3 are arcs, and the arc curvature radii at both ends of the sealing ring 3 are 0.5 to 0.55 times the width of the sealing ring 3; as shown in Figure 10, the two sides of the sealing ring 3 are symmetrical The annular concave curved surface; the cross section of the annular concave curved surface is arc-shaped, and the arc-shaped curvature radius on both sides of the sealing ring 3 is 0.5 to 0.55 times the thickness of the sealing ring 3 .

The thickness of the sealing ring 7 is 0.5-0.55 times the depth of the sealing groove 6, and the material of the sealing ring 7 is an aluminum bronze alloy material.

The thickness of the sealing ring 3 is 0.4 to 0.45 times the depth of the sealing groove 6 ; the material of the sealing ring 3 is fluorine rubber.

The rubber pad 8 is made of fluorine rubber.

The diameter of the large blind hole is 0.15-0.18 times the width of the sealing ring 7 , and the depth of the large blind hole is 0.16-0.17 times the thickness of the sealing ring 7 .

The diameter of the small blind hole is 0.1 to 0.15 times the width of the sealing ring 7 , and the depth of the small blind hole is 0.1 to 0.15 times the thickness of the sealing ring 7 .

Example 2

A piston assembly for a hydraulic cylinder. Except for the following technical parameters, the present embodiment is the same as in Example 1:

The arc length of the rubber pad 8 is 0.007-0.01 times of the complete ring;

The distance between each small blind hole and the adjacent small blind holes is 0.65 to 0.7 times the width of the sealing ring 7;

The thickness of the sealing ring 7 is 0.55-0.6 times the depth of the sealing groove 6;

The thickness of the sealing ring 3 is 0.45-0.5 times the depth of the sealing groove 6;

The diameter of the large blind hole is 0.17-0.2 times the width of the sealing ring 7 , and the depth of the large blind hole is 0.17-0.18 times the thickness of the sealing ring 7 .

Compared with the prior art, this specific embodiment has the following advantages:

(1) In this specific embodiment, multiple groups of blind holes are processed on the outer wall of the sealing ring 7, each group of blind holes is composed of four small blind holes and one large blind hole, and there is hydraulic oil in each group of blind holes. When the piston 4 During movement, the hydraulic oil in the blind hole is taken out, and an oil film is automatically formed in the gap between the piston and the inner wall of the cylinder, which reduces friction and improves lubrication and sealing performance.

(2) In this specific embodiment, concave curved surfaces are processed on both sides of the sealing ring 3. Under the action of high-pressure oil, its lips are opened outward. It also enhances sealing performance when subjected to high pressures.

(3) In this specific embodiment, a rubber gasket 8 is installed at the fracture of the sealing ring 7, which can not only prevent the leakage of high-pressure oil from the circular fracture, but also facilitate disassembly and assembly.

(4) The material of the sealing ring 7 in this specific embodiment is an aluminum bronze alloy with a certain elastic deformation, and the friction coefficient is small, which can speed up the response frequency of the hydraulic cylinder. When there is slight wear on the surface, the sealing ring 7 is disconnected Therefore, it can expand freely to compensate for the gap that is slightly worn, improve the working life of the sealing ring, and automatically adjust the sealing gap to prevent leakage.

Therefore, this specific embodiment has the characteristics of low friction force, high frequency response, high pressure resistance, good sealing performance, long working life, automatic adjustment of sealing gap and convenient disassembly and assembly, and is suitable for hydraulic cylinders with high pressure and low friction.

Claims (6)

1. a kind of piston assembly for hydraulic cylinder, it is characterised in that the piston assembly is by support ring (1), sealing ring group Part (2), sealing ring (3) and piston (4) composition；

Support annular groove (5), difference in two support annular grooves (5) are symmetrically provided at two sides on the cylindrical surface of piston (4) Equipped with support ring (1)；Support of same size, the depth and bearing of support annular groove (5) of the width of annular groove (5) with support ring (1) The thickness of ring (1) is identical；

It is provided with seal groove (6) at the center of two supports annular groove (5) of piston (4), the bottom of seal groove (6) is equipped with sealing ring (3), the outer wall for being close to sealing ring (3) is set with seal ring assembly (2)；The width of seal groove (6) and the width of sealing ring (3) and Seal ring assembly (2) it is of same size, the depth of seal groove (6) is the thickness of sealing ring (3) and the thickness of seal ring assembly (2) The sum of；

Seal ring assembly (2) is the complete circular ring shape being made of sealing ring (7) and rubber pad (8), and the arc length of rubber pad (8) is 0.005~0.01 times of the complete annular；Sealing ring (7) section is rectangle, the section and sealing ring (7) of rubber pad (8) Section it is identical；

The one end for the sealing ring (7) being connected with rubber pad (8) is concave curved surface, and the other end is convex surface, sealing ring (7) it is recessed The intersection of shape curved surface and convex surface and the outer wall of sealing ring (7) is arc-shaped, and the arc curvature radius at sealing ring (7) both ends is equal It is 0.5~0.55 times of sealing ring (7) width；One end with the rubber pad (8) of sealing ring (7) linking is that corresponding convex is bent Face, the other end are corresponding concave curved surface, the friendship of the outer wall of the concave curved surface and convex surface and rubber pad (8) of rubber pad (8) Line is arc-shaped, and the arc curvature radius at rubber pad (8) both ends is 0.5~0.55 times of rubber pad (8) width；

It is equably provided with big-diameter blind hole in the outer wall of sealing ring (7), big-diameter blind hole is located on the center line of sealing ring (7), big-diameter blind hole Spacing is 3.5~4 times of sealing ring (7) width；Across the big-diameter blind hole hole heart and with sealing ring (7) center line in positive 45 ° and in negative Have 2 small blind holes on 45 ° of directions, each small blind hole between adjacent small blind hole at a distance from be sealing ring (7) width 0.6~0.7 times；

Sealing ring (3) is annulus breakaway-element, and one end of gap is concave curved surface, and the other end is convex surface, sealing ring (3) The intersection of concave curved surface and convex surface and the outer wall of sealing ring (3) is arc, the arc curvature radius at sealing ring (3) both ends It is 0.5~0.55 times of sealing ring (3) width；Two sides of sealing ring (3) are symmetrical annular concave curved surface；It is cyclic annular recessed The cross section of shape curved surface is arc-shaped, and the arc curvature radius of sealing ring (3) two sides is 0.5~0.55 times of sealing ring (3) thickness.

2. the piston assembly according to claim 1 for hydraulic cylinder, it is characterised in that sealing ring (7) with a thickness of close 0.5~0.6 times of sealing groove (6) depth, the material of the sealing ring (7) are aluminum-bronze alloy material.

3. the piston assembly according to claim 1 for hydraulic cylinder, it is characterised in that the thickness of the sealing ring (3) It is 0.4~0.5 times of seal groove (6) depth；The material of sealing ring (3) is fluorubber.

4. the piston assembly according to claim 1 for hydraulic cylinder, it is characterised in that the material of the rubber pad (8) For fluorubber.

5. the piston assembly according to claim 1 for hydraulic cylinder, it is characterised in that the diameter of the big-diameter blind hole is 0.15~0.2 times of sealing ring (7) width, the depth of big-diameter blind hole are 0.16~0.18 times of sealing ring (7) thickness.

6. the piston assembly according to claim 1 for hydraulic cylinder, it is characterised in that the diameter of the small blind hole is 0.1~0.15 times of sealing ring (7) width, the depth of small blind hole are 0.1~0.15 times of sealing ring (7) thickness.