KR20130104839A

KR20130104839A - Cylinder block of pump and motor for preventing separation of bushing

Info

Publication number: KR20130104839A
Application number: KR1020120026730A
Authority: KR
Inventors: 조준연; 이기용
Original assignee: 현대중공업 주식회사
Priority date: 2012-03-15
Filing date: 2012-03-15
Publication date: 2013-09-25

Abstract

PURPOSE: A cylinder block of a pump and a motor for an excavator for preventing a bushing from being separated using a swaging technique is provided to prevent a bushing from being separated from a cylinder through the reciprocation motion of a piston. CONSTITUTION: A cylinder block (100) of a pump and a motor for an excavator for preventing a bushing from being separated using a swaging technique comprises a body (110), cylinders (130), and bushings. The body is formed in a cylindrical shape and has a shaft insertion hole (112). The cylinders are formed in the edge of the body and have spaces where pistons reciprocate. The bushings are inserted into the cylinders and are deformed in a flange shape using a swaging technique.

Description

CYLINDER BLOCK OF PUMP AND MOTOR FOR PREVENTING SEPARATION OF BUSHING}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylinder block of an pump and a motor for an excavator, and more particularly, in order to prevent the bushing between a rotating cylinder and a reciprocating piston from being detached from the cylinder block, a swaging technique is applied. It relates to a cylinder block of the pump and motor for excavators that can prevent the departure of the bushing.

In general, a piston pump (Piston pump) or a piston motor (Piston motor), the piston reciprocating inside the plurality of cylinders formed in the cylinder block performs the suction and compression of the fluid to generate a high pressure hydraulic source.

As described above, the piston pump or the piston motor supplies hydraulic oil to a hydraulic cylinder or a hydraulic machine by using a high pressure hydraulic source generated as described above, or provides power for operation of various industrial machines, ship equipment and heavy construction equipment. It will act as a pump and a motor to make it possible.

Among the cylinder blocks used in the piston pump or the piston motor, in the swash plate type cylinder block in which the insertion depths of the pistons are different from each other, the piston and the cylinder are used to increase the discharge pressure of the fluid by the reciprocating motion of the pistons. It is desirable to reduce the clearance in the main sliding part between. However, many problems that arise in relation to the tribology aspect are obstacles to reducing this gap.

In particular, the gap between the piston and the cylinder has a great influence on the performance characteristics such as the volumetric efficiency and reliability of the piston pump or the piston motor due to the lubrication characteristics, so an accurate understanding thereof is required.

And in the narrow gap between the cylinder and the piston reciprocating inside the cylinder at high speed, a thin film flow of hydraulic oil creates an asymmetric pressure distribution in the circumferential direction of the piston, which results in It acts as a hydraulic lateral force perpendicular to the direction of movement of the piston.

These lateral forces can increase frictional forces acting on the piston, or cause excessive wear on the piston and the inner wall of the cylinder or direct contact between the piston and the cylinder, resulting in fluid locking, which leads to an unusable state.

Therefore, in order to solve this problem, along each cylinder inner wall, a bushing of a tubular shape having excellent abrasion resistance and lubrication performance can be provided to impart wear resistance and lubrication performance to the reciprocating motion of the piston. Typically, copper or copper alloy materials) are used to directly fit the cylinder inner surface of the cylinder block serving as the base material.

However, such a bushing is press-fitted by adjusting the press-in amount, in which case the press-in bushing may be separated from the cylinder block.

Therefore, while reducing the manufacturing cost of the cylinder block, there is a need for a cylinder block that prevents the bushing from detachment or deformation through the piston reciprocating motion.

Prior art related to the present invention is Republic of Korea Patent Publication No. 10-0605668 (July 31, 2006).

The present invention provides a cylinder block of an excavator pump and a motor in which the bushing is pressed into the inner circumferential surface of the cylinder by a swaging technique to prevent the piston reciprocating bushing from the cylinder block. have.

According to the technical idea of the present invention, the body is made of a cylindrical shape, having a shaft insertion hole in the center; A cylinder formed at an edge of the body to provide a space for the piston to reciprocate, and having a stepped portion at the mouth; And a bushing pressed into the inner circumferential surface of the cylinder and deformed into the flange shape by a swaging technique, which is a kind of forging, and provides a cylinder block of an excavator pump and a motor.

It is preferable that the bushing provides a lubrication function to the cylinder.

The bushing is preferably made of a high strength brass material.

The bushing may include a press-fitting part pressed into the inner circumferential surface of the cylinder; And a flange portion extending from the press-fit portion and having a size corresponding to the step.

According to the cylinder block of the pump and motor for excavators that can prevent the departure of the bushing by applying the swaging technique of the present invention, by pressing the bushing into the cylinder by the swaging technique, the bushing is released through the piston reciprocating motion It provides a preventable effect.

1 is a view schematically showing a cylinder block of a pump and a motor for an excavator that can prevent the departure of the bushing applying the swaging technique according to an embodiment of the present invention,
2 and 3 are views in which the bushing is press-fitted into the cylinder through the swaging technique in the cylinder block of the pump and motor for excavators that can prevent the departure of the bushing by applying the swaging technique according to an embodiment of the present invention. The figure is shown to explain.

Hereinafter, with reference to the accompanying drawings will be described with respect to the cylinder block of the pump and motor for excavators that can prevent the departure of the bushing applying the swaging technique according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other features and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which: It is intended that the invention be described in its entirety by reference to the appended claims and their equivalents.

Like reference numerals refer to like elements throughout.

In addition, the size of the components constituting the invention in the drawings are exaggerated for clarity of the specification, and if any component is described as "existing inside or connected to the other components", A component may be installed in contact with the other component, may be installed at a predetermined distance, and when installed at a distance, a third for fixing or connecting the component to the other component The description of the means of may be omitted.

1 is a view schematically showing a cylinder block of an excavator pump and a motor that can prevent the departure of the bushing by applying the swaging technique according to an embodiment of the present invention.

Referring to Figure 1, the cylinder block 100 of the pump and motor for excavators that can prevent the departure of the bushing to which the swaging technique according to an embodiment of the present invention is large, the body 110, the cylinder 130 ) And a bushing (150 in FIG. 2).

The body 110 is formed in a cylindrical shape and has a shaft insertion hole 112 in the center.

The cylinder 130 is formed at the edge of the body 110. The cylinder 130 provides a space in which the piston reciprocates.

Bushing (150 in FIG. 2) is made of a form that is press-fit into the inner peripheral surface of the cylinder (130).

Detailed description of the configuration and the operation relationship for the configuration will be described later in detail with reference to FIGS.

2 and 3 are views in which the bushing is press-fitted into the cylinder through the swaging technique in the cylinder block of the pump and motor for excavators that can prevent the departure of the bushing by applying the swaging technique according to an embodiment of the present invention. Figure is for explaining.

2 and 3 at the same time, the cylinder block 100 of the pump and motor for excavators that can prevent the departure of the bushing to which the swaging technique according to an embodiment of the present invention is large, the body 110 and And a cylinder 130 and a bushing 150.

Since the above configurations are the contents described above with reference to FIG. 1, redundant descriptions will be omitted. However, even the above description may include a part overlapping partially to help the understanding of the drawings. In addition, in Figures 2 and 3 will be described with respect to the description and the operational relationship between each configuration.

The illustrated cylinder 130 provides a space in which the piston reciprocates, and has a step 132 at the mouth.

The bushing 150 is press-fitted into the inner circumferential surface of the cylinder 130. At this time, the bushing 150 is deformed into a flange shape using a swaging technique, which is a kind of forging. In other words, as shown, the press-fit bushing 150 is deformed into a flange shape by using a separate jig 10. At this time, the press-fit relationship with the cylinder 130 and the bushing 150 will be described later.

Here, the swaging is a type of compression processing means that compression molding of the wire, pipe, bar, etc. between the tools. Types of such swaging include rotary swaging, extrusion swaging, drawing swaging, and spinning swaging.

The bushing 150 provides a lubrication function to the cylinder 130. At this time, the bushing 150 is preferably made of a high-strength brass material.

High-strength brass means what added Ni, Al, Sn, Si, Mn, Fe, etc. to copper- zinc alloy here. These high-strength brasses have high tensile strength and toughness, and are used in machinery, aircraft, and ship parts as well as high-grade structural materials.

As shown, when the bushing 150 is press-fitted into the inner circumferential surface of the cylinder 130, the above-mentioned swaging technique is used to prevent the bushing 150 from being detached.

At this time, through the jig 10 shown in the process of the swaging technique, the shape of the bushing 150 is deformed into a flange shape as shown in FIG. At this time, the bushing 150 may be effectively pressed into the inner circumferential surface of the cylinder 130. Therefore, the present invention can prevent the bushing 150 from being separated from the cylinder 130 by the deformation through the swaging technique.

As described above, the cylinder block of the pump and motor for excavators that can prevent the departure of the bushing to which the present inventor's swaging technique is applied, presses the bushing into the cylinder by the swaging technique, and the bushing through the piston reciprocating motion This can provide an effect that can prevent the departure.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

10 jig 100: cylinder block of pump and motor for excavator
110: body 112: shaft insertion hole
130: cylinder 132: step
150: bushing

Claims

A cylindrical shape, the body having an axial insertion hole in the center thereof;
A cylinder formed through the rim of the body to provide a space in which the piston reciprocates, and having a stepped portion at the mouth; And
The cylinder block of the pump and motor for excavators including a bushing press-fitted into the inner peripheral surface of the cylinder, deformed into the flange shape by a swaging technique, a kind of forging.

The method of claim 1,
The bushing is,
Cylinder block of the pump and motor for excavators, characterized in that to give a lubricating function to the cylinder.

The method of claim 1,
The bushing is,
Cylinder block of the pump and motor for excavators, characterized in that made of high-strength brass material.

The method of claim 1,
The bushing is,
A press-fitting part pressed into the inner circumferential surface of the cylinder; And
A cylinder block of the pump and motor for excavators, characterized in that it comprises; a flange portion formed extending in the press-fit portion, the size corresponding to the step.