JPH0527254Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an apparatus for removing burrs generated in a cast product within a mold.

(Prior Art) For example, in a cast product in which a through hole is formed using a cast pin, burrs are generated along the mating surfaces and the like. This is because since the cast pin is made of metal, a certain amount of space must be provided between the mating surfaces in consideration of its thermal expansion, and the casting material flows into that space.

Conventionally, when removing burrs generated on such mating surfaces, a burr removal device provided in a trimming press has generally been used.

An example of this trimming press and deburring device is shown in FIG. 6 and briefly described. A lower die 4 on which a cast product 3 is placed is fixed to a base 2 attached to a lower frame 1. . In addition, a base 6 attached to the upper die frame 5 is provided with cutting blades 7 for removing burrs generated on both ends and sides of the cast product 3 (in the direction perpendicular to the plane of the paper in the figure), and An upper mold 8 is provided which holds the mold 3 together with the lower mold 4.

A deburring device 10 for removing burrs 9 generated on the mating surfaces inside the cast product 3 includes a cylinder device 11 attached to the side of the trimming press.
and a movable punch pin 13 connected to the piston rod 12 of the cylinder device 11 and movable toward the burr 9 from the side of the trimming press.

To explain the operation of the trimming press having this configuration, the cast product 3 formed in the casting process is placed on the lower mold 4, and then the upper frame 5 is lowered. At this time, the upper mold 8 descends in advance of the cut 7, and firmly holds the cast product 3 with the lower mold 4. Then, as the cutting blade 7 descends, the burrs on both ends and sides of the cast product 3 are cut off and removed. Subsequently, the movable punch pin 13 is moved forward by the operation of the cylinder device 11 from the side, and the burr inside the cast product 3 is
Press and remove.

In addition, as described above, the method of removing burrs by the operation of a cylinder device was developed by the present applicant.
There is a technique disclosed in Publication No. 59-156731.

(Problems to be Solved by the Invention) However, in the above-mentioned trimming press provided with the deburring device 10, the structure of the trimming press is complicated because the trimming press must be provided with a structure through which the movable punch pin 13 is inserted. Furthermore, since the trimming press and the deburring device 10 are operated separately,
The timing of each operation must be precisely controlled. As a result, setups such as operation control and mold matching became complicated, leading to problems such as increased equipment costs and decreased productivity.

The present invention was developed in view of the above problems, and its purpose is to simplify the deburring process by removing the burrs generated by the casting pins within the mold. .

(Means for solving the problems) The means according to the present invention for solving the above problems are as follows. In an apparatus for forming a through hole with a core pin in a casting product cast using a moving core, and removing burrs generated when forming the through hole, the core pin is moved relative to the moving core. The casting pin is provided so as to be movable, and the movement range of the casting pin is set to a moving length that allows the casting pin to pass through a through hole formed in the cast product.

(Function) Since the present invention is constructed as described above, it has the following functions. That is, since the core pin is provided so as to be movable relative to the movable core, it becomes possible to move the core pin independently of the movable core. Furthermore, the movement range of the cast-out pin is set to a length that allows the cast-out pin to pass through the through-hole formed in the cast product, so that a cavity can be formed that takes into account the thermal expansion of the cast-out pin. In addition, by passing a cast-out pin through the through-hole formed in the cast product, it becomes possible to remove burrs from the through-hole.

(Example) Next, an example of the present invention will be described based on the drawings.

First, the configuration of this embodiment will be explained using FIG. 1 and FIG. 4. The present embodiment relates to removing burrs generated in the through-hole w1 of a cast product W having a through-hole at the bottom, such as a transmission case of an automobile.

14 is the upper mold, 15 is the lower mold, 16, 17
are movable cores provided facing each other. The upper die 14, the lower die 15, and the movable cores 16 and 17 form a cavity 18 as shown in FIG.

One moving core 16 is composed of a core body 19, a core holder 20 that holds the core body 19, and a cylinder device 22 having a piston rod 21 fixed to the core holder 20. Piston rod 21 by actuation of device 22
Due to the expansion and contraction of the core body 19, the upper mold 14 and the lower mold 1
It is now possible to advance and retreat between 5 and 5.

Moreover, the other moving core 17 has a cavity 23 inside.
a core body 24 provided with a core body 24, a core holder 25 that holds the core body 24, a pair of slide plates 26 that are movable within the cavity 23 provided in the core body 24, and a pair of slide plates 26 that are movable within the cavity 23 provided in the core body 24; 26 and base 27a
A cylinder device 29 includes a plurality of cast-out pins 27 which are held in place and whose tips protrude forward from the core body 24, and a piston rod 28 that is connected to the slide plate 26 and slidably passes through the core holder 25. It is composed of. Then, by operating the cylinder device 29 and expanding and contracting the piston rod 28, the cast pin 27 is inserted into the core body 2.
The slide 26 moves independently of the core body 24 within the movement range of the slide 26 that moves within the cavity 23, and the slide 26 moves between the core body 24 and the core body 24. When the core pin 27 comes into contact with the child holder 25, it moves together with the core body 24.

The range of movement of the slide 26 is such that the cast pin 27 can pass through the through hole w1 formed in the cast product W.

The core holders 20 and 25 of the movable cores 16 and 17 have protrusions 20a and 25 that fit into the recesses 14a and 14b formed in the upper die 14, respectively.
a is formed, and the recesses 14a, 1 of the upper mold 14
4b, each core body 19, 24 is positioned at a regular position.

The operation related to the above configuration will be explained using FIGS. 1 to 5.

First, as shown in FIG.
From the preparatory stage in which the piston rods 21, 28 of 2, 29 are shortened, the respective cylinder devices 22, 29 are operated to extend the piston rods 21, 2.
Extend 8. Along with this, the core body 19, 2
4 and the cast-out pin 27 move forward, and as shown in FIG. 5, the tip of the cast-out pin 27 provided on the other core body 24 comes into contact with the front surface of one core body 19 and stops. .

Next, the upper mold 14 is lowered to fit the protrusions 20a, 25a of the core holders 20, 25 into the recesses 14a, 14b of the upper mold 14, and the core bodies 19, 2
Perform positioning in step 4. Since the cast piston 27 is movable independently of the movable core 17, by shortening the piston rod 28 of the cylinder device 29 of the movable core 17, the slide plate 2
6 to the rear end side of the cavity 23 of the core body 24 (the state shown in FIG. 1). At this time,
As shown in FIG.
A distance Δt of about 0.2 to 0.5 mm is set. The reason why the distance Δt can be set in this manner is that the movement range of the cast pin 27 is set to a length that allows it to pass through the through hole w1. This is set in consideration of thermal expansion, but the casting material flows into this gap Δt, causing burrs to occur.

Next, the upper mold 14, the lower mold 15, and the moving core 1
Molten casting material is injected into the cavity 18 formed by the casting pins 6 and 17 and the cast-out pin 27.

When casting is completed, the upper mold 14 is raised, and then one of the core bodies 19 is retreated. At the same time, by extending the cylinder device 29 of the other moving core 17 and moving the slide plate 26 forward relative to the core body 24, the burrs generated due to the above-mentioned distance Δt are pressed and removed. .
(Situation shown in FIG. 3) In this way, the burrs can be removed by the core pin 27 only when the core pin 27 moves relative to the movable core 24 and within its moving range. This is because the length is such that it can pass through the through hole w1 formed in the cast product W, and in the case of this embodiment, the length of the penetrating movement is Δt as shown in FIG.

Then, the piston rods 21, 28 of the cylinder devices 22, 29 of the moving cores 16, 17, respectively.
is shortened and the core bodies 19, 24 are returned to their pre-molding positions, completing one cycle of the casting process.

(Effects of the invention) As explained in detail above, the invention enables the casting pin to move relative to the movable core, and sets the moving length to a length that allows it to pass through the through hole formed in the cast product. Since the hole is made straight, a cavity can be formed, and burrs in the through hole can be removed using a cast pin.

In this way, since the cavity is formed by the cast-out pin and the burrs are removed using the cast-out pin, a dedicated burr removal device is not required.

Therefore, equipment costs are reduced and productivity is improved.

Moreover, since deburring is performed with the casting pin forming the through hole w1, the burr can be removed reliably and accurately, and a mold with stable quality can be provided.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view showing the mold clamping state of an embodiment of the present invention, FIG. 2 is an enlarged view of the tip of the casting pin shown in FIG. 1, and FIG. 3 is the one shown in FIG. 1. FIG. 4 is a vertical cross-sectional view showing the mold opening state of the example shown in FIG.
FIG. 5 is a vertical sectional view showing the state of the embodiment shown in FIG. 1 before the molding operation, FIG. 6 is a longitudinal sectional view showing the state of the embodiment shown in FIG. FIG. 3 is a longitudinal cross-sectional view showing an example of a trimming press for removing burrs from the product W. 14... Upper mold, 15... Lower mold, 16, 17...
Moving core, 27...Cast pin.

Claims (1)

[Scope of utility model registration request] In an apparatus for forming a through hole with a core pin in a casting product cast using a moving core, and removing burrs generated when forming the through hole, the core pin is moved relative to the moving core. It is movable to the
A deburring device for a casting product, characterized in that the movement range of the casting pin is set to a moving length that allows the casting pin to pass through a through hole formed in the casting product.