WO2015051584A1

WO2015051584A1 - Method for machining and shaping rocker arm frame

Info

Publication number: WO2015051584A1
Application number: PCT/CN2013/091167
Authority: WO
Inventors: 徐纳
Original assignee: 杭州新坐标科技股份有限公司
Priority date: 2013-10-09
Filing date: 2013-12-31
Publication date: 2015-04-16
Also published as: CN103600005A; CN103600005B

Abstract

Disclosed is a method for machining and shaping a rocker arm frame. The rocker arm frame includes an integrally shaped ball socket (5), a curved crown (3) and two symmetric side walls (1, 2), wherein one end of the two side walls is connected to the H-shaped curved crown, the other end is connected to the ball socket, a bottom part of the ball socket is provided with a small oil hole (6), and the side walls are each provided with an pin shaft hole. The method of machining and shaping comprises the following steps: blanking of a rocker arm profile, wherein a plate-shaped workpiece of the rocker arm is punched out using a punch; pre-bending, wherein the plate-shaped workpiece is pre-bent, forming a W-shaped workpiece; and lateral extrusion, wherein the lateral extrusion is performed on the W-shaped workpiece, forming the primary finished product of a rocker arm frame having the required H-shaped curved crown. The method eliminates the problem of severe localised attenuation in the course of shaping the side walls.

Description

Processing and forming method of rocker frame

The invention belongs to the field of engine parts manufacturing, and particularly relates to a valve rocker arm for controlling the opening and closing of a valve of an engine valve train or a roller rocker arm with a bearing. BACKGROUND OF THE INVENTION With the development of engine technology, the manufacturing process of the main component rocker arm of the valve rocker arm or the roller rocker arm has undergone stages of casting molding, hot forging forming, cold stamping forming, etc. Currently, advanced production processes are advanced. Continuous cold stamping forming process, cold drawing forming rocker frame has the advantages of light weight, high strength, good consistency and high production efficiency. The existing rocker frame structure is shown in Figure 1: The structure of the rocker frame with the valve is "H" type, and the side wall needs 180° bending when forming. The traditional molding process is sheet material. First bend into a "U" shape, then squeeze it up into a "H" shape. The disadvantages of this molding process are: 1. The partial stretching and thinning of the side wall is serious, affecting the structural strength, and the risk of fatigue fracture; 2. There is a gap between the two side walls, which are not attached to each other, so the rigidity is poor. When working, it may produce abnormal vibration and affect the normal operation of the engine. Summary of the invention

The purpose of the invention is to provide a new processing method for the rocker frame, which is a roller rocker arm component of a valve mechanism with hydraulic automatic compensation gap, which solves the problem that the crown sidewall forming process is severe. The problem of thinning and eliminating the gap between the two side walls allows the two side walls to fit snugly. To achieve the above object, the present invention adopts the following technical solutions:

A processing method for forming a rocker frame, the rocker arm frame comprises an integrally formed bottom plate and a side wall, the bottom plate has an H-shaped crown at one end, a ball socket at the other end, a small oil hole at the bottom of the ball socket, and the side wall is opened There is a pin hole, characterized in that the forming method comprises the following steps:

A. The shape of the rocker frame is punched out, and the plate-shaped workpiece of the rocker frame is punched out by the punching machine;

B. Pre-bending, pre-bending the plate-shaped workpiece, and forming a W-shaped portion of the crown;

C. Lateral extrusion W-shaped, the crown portion forms a primary finished rocker arm with the desired H-shape.

The processing and molding method has the following steps:

a, punching the positive pin hole, placing the raw steel strip in the progressive die device, and punching out the positive pin hole;

b. The shape of the rocker frame is punched out, and the plate-shaped workpiece of the rocker frame is punched out by the punching machine;

c. Pre-bending, pre-bending the plate-shaped workpiece to form a W-shaped portion of the crown;

d. lateral extrusion, laterally pressing the W-shaped portion of the crown portion to form a primary finished rocker frame having a desired H-shaped crown;

e. Simultaneously extrude the ball socket and the curved surface of the crown to ensure the position of the ball socket and the curved surface of the curved crown; f, the side punch pin hole;

g, blanking;

h, heat treatment;

i. Laser perforation, using a laser perforation device to process small oil holes in the ball socket.

The processing method includes a small oil hole laser perforation step.

The laser perforation step is after the heat treatment step.

A pre-bending step is preceded by a step of pressing, and a groove is provided at the W-shaped bend.

The crown part is first bent into a "W" shape, and then the side wall is pressed laterally to form the crown portion into an "H" shape. The object of the invention is also to provide a new small oil hole processing technology, improve the production efficiency of the rocker frame and eliminate the risk of small oil hole clogging. The bottom of the ball socket of the rocker arm is provided with a small oil hole. When the engine is working, the high-pressure lubricating oil delivered by the oil pump is sprayed out from the small oil hole, and the roller drive pair on the cam and the roller rocker arm is lubricated. The aperture is generally less than 0.5 mm. The prior art is punched out on the progressive die, which requires multiple stations to be realized, the mold structure is complicated, the mold material and the machining precision are required to be high, the punch is easily broken and the life is low in the work, and the replacement of the punch takes time. Laborious, affecting the production cycle and processing efficiency of the entire progressive die. In addition, the small oil hole of the rocker frame has a risk of clogging of small oil holes during subsequent processing steps such as heat treatment and rolling.

The small oil hole of the rocker frame of the invention is not subjected to a punching process, but is placed on the rocker frame for forming and heat treatment, and the small oil hole is processed by the laser perforating device.

The beneficial effects of the process of the present invention over prior art process molding techniques are:

1. The wall thickness of the two side walls is relatively uniform, and there is no obvious local thinning part, so the strength is good.

2. The 180° bend of the side wall is extruded into two “H” shapes by two lateral sliders. After forming, the two side walls can be closely fitted and the structure is rigid.

3. Pre-bend into "W" type, and then side-squeezed into "H" type, compared with pre-bending into "U" type, and then forced to squeeze up into "H" process, the mold is weak. , long life.

4. Using the laser perforation process, the structure of the progressive die is simplified first, the failure rate and the number of mold replacements are reduced, and the production efficiency of the progressive die is improved. Secondly, the risk of clogging caused by other processes is eliminated. .

5. The size of the small oil hole on the rocker frame has a great influence on the oil pressure loss of the oil pump. Therefore, it is desirable to make the oil hole as small as possible, but it is difficult to punch a small hole of 0.3mm or less with a mold. Laser wear Hole machining of small holes of 0.3 mm or less is very easy and convenient, with high production efficiency and relatively low cost. DRAWINGS

Figure 1 is a three-dimensional structure diagram of the equiaxed side of the rocker arm.

Fig. 2 is a schematic view in which the crown portion is pre-bent into a "U" shape and then extruded upward into a "H" shape. Fig. 3 is a schematic view of the crown portion being pre-bent into a "W" type and then laterally extruded into a "H" shape.

Figure 4 is a schematic cross-sectional view of the rocker arm.

Figure 5 is a schematic illustration of a second embodiment of the rocker boom process.

Figure 6 is a schematic illustration of a second embodiment of the rocker boom process.

Among them, 1, side wall 1; 2, side wall 2; 3, crown; 4, pin hole; 5, ball socket; 6, small oil hole; 7, two side walls close together; 8, two sides Uniform wall thickness; 9, groove on the plane; 10, circular groove under the arc; 11, circular groove on the arc; 12, V-shaped lower groove; 20, the thinner side wall 2; 30, now Technical crown; 70, gap; 80, intersection; 100, U-shaped workpiece; 101, the workpiece of the present invention; 300, the crown profile of the present invention. detailed description

The specific embodiments of the present invention are further described below with reference to the accompanying drawings: The rocker frame adopts a process of continuously forming a steel strip on a progressive die. The main steps are: punching the positive pin hole, punching the rocker frame shape, pre-folding "W" shape, side extruded into "H" shape, one-time simultaneous extrusion of ball and socket curved surface, side punch pin hole, blanking, etc. As shown in Fig. 2, the conventional molding process is that the crown portion is first bent into a U-shaped workpiece 100, and then the upper mold is pressed against the side wall-1, and the lower mold is extruded upward to be "H" type, due to the size L. The limitation is that when the upward pressing, the intersection portion 80 of the side wall 20 and the crown 30 produces severe local stretching and thinning, the strength is much reduced, and there is a risk of fatigue fracture during work; The wall 2 does not fit together, and there is a large gap or gap 70. The rigidity is poor, which affects the structural rigidity of the rocker frame. Vibration and abnormal noise will occur when the machine is working.

The molding process of the present invention is shown in Fig. 3. During the molding process, the side wall 1 and the side wall 2 are more uniformly deformed, and there is no obvious stretching and thinning phenomenon. After laterally pressing into "H", the side wall 1 It is closely attached to the side wall 2 and the rigidity of the crown 3 is good. Therefore, the strength and rigidity of the entire rocker frame are superior to the conventional molding process. As shown in the figure, the two side walls are closely attached to each other, and the thickness of the two side walls is uniform. 8.

As shown in Fig. 4, the small oil hole 6 of the processing processing rocker frame adopts the method of laser perforation, which is performed after the steps of forming the rocker frame, rolling and deburring, heat treatment, shot blasting, etc., after laser perforation, ultrasonic waves are applied. Cleaning, the small oil hole is not blocked, and the hole diameter of the laser perforation can be made smaller, can reach 0.2mm or less, and the processing efficiency is higher, which can reach more than 60 pieces per minute. The traditional progressive die processing beat is in every minute. 30 or so. The traditional progressive die has a small oil hole, the hole diameter is more than 0.3mm, and multiple working stations are required to punch out. The punching die is a complicated wedge wedge structure, which requires high requirements on the die material and processing precision. The life of the punch is short and easy to malfunction. The frequency of replacing the mold is high, and the scrap rate of the rocker frame is high. The process of roll throwing, heat treatment and shot blasting after the rocker frame is formed may block the small oil hole in the final product. It is necessary to increase the inspection procedure of whether the oil hole is blocked. In contrast, the new laser perforation process replaces the traditional mechanical machining oil hole process, which has the advantages of high production efficiency and low cost.

The above is only one embodiment of the processing technique of the rocker frame, and the present invention can also have various process changes, such as FIG. 5 and FIG. 6, before the pre-bending of the rocker frame is formed into a "W" type step. The step of adding the groove is increased, and the other forming steps are the same as in the first embodiment.

The groove depth is less than one third of the plate thickness. Excessive pressure grooves will affect the overall mechanical stability, and shallow grooves will not achieve the desired results.

The shape of the pressure groove one is a plane or a circular arc surface, and the shape of the pressure groove two is a circular arc surface or an inverted V shape. The above-described arrangement of the shape of the groove is more advantageous for bending.

The advantages of increasing the groove step: 1. Reduce the bending forming force; 2. Make the symmetry good when bending; 3. Subtract The phenomenon of stacking at small bends; 4. Reducing the forming force when pre-bending into "W" type and side extrusion into "H", there is;

Claims

claims

1. A method of processing and forming a rocker arm frame. The rocker arm frame contains an integrally formed ball socket, a curved crown and two symmetrical side walls. One end of the two side walls is connected to the H-shaped curved crown, and the other end is connected to the ball socket. , a small oil hole is provided at the bottom of the ball socket, and a pin hole is provided on the side wall. It is characterized in that the processing and forming method includes the following steps:

A. Blanking the shape of the rocker arm frame, using a punch to punch out the plate-shaped workpiece of the rocker arm frame;

B. Pre-bending, pre-bending the plate-shaped workpiece to form a W-shaped workpiece;

C. Lateral extrusion: perform lateral extrusion on the W-shaped workpiece to form a primary finished rocker arm frame with the required H-shaped curved crown.

2. The processing and forming method of the rocker arm frame according to claim 1, characterized in that the processing and forming method consists of the following steps:

a. Punch the positive pin hole, place the raw steel strip in the progressive die equipment, and punch out the positive pin hole;

b. Blanking the shape of the rocker arm frame, using a punch to punch out the plate-shaped workpiece of the rocker arm frame;

c. Pre-bending, the plate-shaped workpiece is pre-bent, and the curved crown part is formed into a W shape;

d. Laterally squeeze the W-shape, and the curved crown part forms a primary finished rocker arm frame with the required H-shape;

e. Extrude the ball socket and the curved crown surface at the same time at one time to ensure the position accuracy of the ball socket and the curved crown surface; f. Side punch pin shaft hole;

g. Blanking;

h. Heat treatment;

i. Laser perforation: use laser perforation equipment to process small oil holes in the ball socket.

3. The processing and forming method of the rocker arm frame according to claim 1, characterized in that the processing and forming method includes a step of laser perforation of small oil holes.

4. The processing and forming method of the rocker arm frame according to claim 3, characterized in that the laser perforation step is after the heat treatment step. . The processing and forming method of the rocker arm frame according to claim 1 or 2, characterized in that a pressing groove step is provided before the pre-bending step, and a pressing groove is provided at the bending part of the W-shaped workpiece.

. The processing and forming method of the rocker arm frame according to claim 5, characterized in that the depth of the pressure groove is less than one-third of the plate thickness.

. The processing and forming method of the rocker arm frame according to claim 5, characterized in that the shape of the first pressure groove is a flat surface or an arc surface, and the shape of the second pressure groove is an arc surface or an inverted V shape.