JPS6227949B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a burr removal method for removing burrs around the through-hole of a die-cast product having a through-hole. Although not particularly limited, it is effective for use in, for example, the frame of an alternator.

(Description of Prior Art) Conventionally, a process as shown in FIG. 1 has been used as a method for deburring die-cast products having through holes. That is, the burrs on the outer periphery of the die-cast product are removed by a trimming process Y, then the thin film-like burrs 2 formed in the through-holes are removed by a cutting process U as shown in FIG. This consisted of a shot process K in which the burrs on the end surfaces of the through holes 3 were completely removed by transporting the holes into the hole and spraying small particles at high speed.

However, this conventional method requires a special cutting process, especially when a large number of through holes 3 are formed in one die-cast product.
There was a problem in that the time required for cutting was extremely long, making it impossible to manufacture die-cast products at high speed.

On the other hand, as shown in FIG. 3, a method using a punching process instead of the cutting process U is also known. As shown in FIG. 4, the burr 2 formed in the through hole is punched out using a punching jig 4. However, since this punching jig reciprocates in an inclined downward direction S with respect to the axial direction O of the die-cast product 1, when there are multiple through holes 3, the punching jig 4 is moved multiple times while moving the die-cast product 1.
had to be moved back and forth. Therefore,
There was a problem that high-speed manufacturing was not possible. Also,
In order to punch out the burrs 2 of a large number of through holes 3 at once, a large number of burr removal jigs 4 must be provided, and since the reciprocating directions S of each burr removing jigs 4 are different from each other, The mechanism required for the movement becomes extremely complex. Therefore, there is a drawback that the deburring device becomes expensive.

(Object of the present invention) The present invention has been devised in view of the above points, and it is possible to remove burrs from a plurality of through holes at the same time.
The purpose is to significantly shorten the deburring process.

(Structure of the present invention) Therefore, in the present invention, a plurality of bending punches facing the plurality of through-holes are inserted into each of the through-holes along the axial direction of the die-cast product, and the burr formed in the through-hole is removed from the end surface of the through-hole. The structure is such that the material is bent along the same direction, and then the burrs are removed by a shot process.

(Description of Embodiment) An embodiment of the present invention will be described below based on the drawings. FIGS. 5 and 6 show an example of a die-cast product to which the method of the present invention is applied, and in this example, it is a frame for an automobile alternator. and,
This die-cast product 1 is molded from an aluminum die-cast alloy (ADC12), and has a large number of through holes 3 formed on its outer peripheral side surface.

Since this die-cast product solidifies in the mold space between the mating surfaces of the movable mold and the fixed mold in the die-casting machine, a thin film-like burr 2 is integrally formed around the die-cast product 1 and inside the through hole 3. is formed.

In this example, a burr removal step for removing burrs 2 formed in the through holes 3 is performed as shown in FIG.

That is, the burrs formed on the outer periphery of the die-cast product 1 are removed by the trimming process Y. In this trimming process Y, the die-cast product 1 is placed in a platform shape having a punched hole having the same shape as its outer circumference, and in this state, the die-cast product 1 is inserted into the punched hole to remove burrs on the outer circumference. be.

Next, the burr 2 formed in the through hole 3 of the die-cast product 1 from which the burr on the outer periphery has been removed is bent in a bending step H.

This folding step is carried out using a folding press device as shown in FIG. 10 in Figure 8
Reference numeral 11 indicates a fixed base, a guide bar vertically protrudes from the fixed base, and 12 a movable table slidably installed on the guide bar. The movable table 12 receives driving force from a hydraulic piston (not shown) and reciprocates in the vertical direction in the drawing.

Reference numeral 13 denotes a holding stand disposed on the fixed base 10, and the die-cast product 1 is placed on this holding stand 13 by a carrying device (not shown). A deburring pin 14 with a guide and a bending punch 15 are disposed on the movable table 12 at a position facing the die-cast product 1. In particular, the deburring pin 14 with guide is arranged at a position facing the through hole 1a in the center of the die cast product 1, and the bending punch 15 is arranged at a position facing the through hole 3 at the side circumference of the die cast product 1. has been done. And deburring pin 1 with guide
The gap L between the tip of the die-cast product 1 and the bending punch 15 is smaller than the gap l between the bending punch 15 and the die-cast product 1.

A tapered guide portion 14a is formed at the tip of the guide-equipped deburring pin 14, and the die-cast product can be accurately positioned by this guide portion 14a. On the other hand, the tip 15a of the bending punch 15 is formed into a flat shape, and when the tip 15a comes into contact with the burr 2, the burr can be bent.

That is, when the movable base 12 is moved toward the fixed base 10 by a hydraulic piston (not shown) (the state shown in FIG. 9), the die-cast product 1 is first accurately positioned using the guide deburring pin 14. Thereafter, the burr formed in the through hole 3 of the die-cast product 1 is bent along the edge of the through hole 3 using the tip of the bending punch 15. Especially this bending position W
is along the lower end surface of the through hole 3, as shown in FIG.

Since the burr is plastically deformed at the bending position W, the metal structure at that part W is hardened and becomes brittle.

Next, the die-cast product is carried out from the bending press device and transferred to a shot device 20 as shown in FIG.
Make a shot. In this shot process K, aluminum alloy particles 21 having a particle size of about 1.0 to 1.5 mm are collided with the die-cast product 1 at high speed (73 m/sec). At this time, since the die-cast product is rotated by the rotating roller 22, the particles 21 collide with the die-cast product 1 from all directions. and,
The burr 2 formed on the die-cast product in this state
Since the W to be bent in the above process is very fragile, the burr 2 is removed from the bending position W by the collision of the particles 21.

The deburring process is completed through the above steps, and then the die-cast product 1 is further precisely finished in the cutting process W.

In addition, in the above example, after the burrs on the outer periphery of the die-cast product 1 are removed by the trimming process Y, the through-hole 3 is removed.
Although the burr 2 was bent, the above trimming step Y
It is also possible to perform the folding step H and the bending step H at the same time.

(Effects of the Present Invention) As explained above, according to the method of the present invention, burrs generated in a plurality of through holes formed in a die-cast product can be efficiently removed. Therefore,
It has the excellent effect of significantly shortening the time required to deburr die-cast products.

[Brief explanation of the drawing]

Fig. 1 is a process diagram showing a conventional deburring method, Fig. 2 is a sectional view explaining the cutting process shown in Fig. 1, Fig. 3 is a process diagram showing a conventional deburring method, and Fig. 4 is a process diagram showing the cutting process shown in Fig. 1. 5 is a front view showing an example of a die-cast product; FIG. 6 is a sectional view taken in the direction of the - arrow in FIG. 5; FIG. 7 is a process diagram showing an example of the method of the present invention; 8 and 9 are sectional views showing the bending press device used in the bending process shown in FIG. 7, FIG. 10 is a sectional view showing the punching process using the device shown in FIG. 8, and FIG. 11 is a sectional view showing the shot process shown in FIG. 7. 1 is a perspective view showing a shot device used for 1...Die-cast product, 2...Burr, 3...Through hole, 1
5...Folding punch.

Claims (1)

[Claims] 1 A method for removing burrs from a die-cast product having a plurality of through-holes, in which a bending punch is inserted into the through-holes along the axial direction of the die-cast product, and burrs formed around the through-holes are removed along the periphery of the through-holes. A method for removing burrs from a die-cast product by bending the die-cast product by bending the die-cast product, and then spraying small particles onto the die-cast product at high speed to remove the burr along the bend line.