JPH0545348B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] <Industrial Application Field> The present invention relates to a cutting method for removing unnecessary parts such as runners from a released cast molded product.

<Conventional technology> In casting molding, it is necessary to remove unnecessary parts such as sprues and runners from the released molded product.
Conventionally, this type of cutting operation is usually carried out using a hacksaw or the like after the molded product has sufficiently cooled.

<Problems to be Solved by the Invention> However, according to this prior art, it is difficult to shorten the cycle time due to the cooling time required, or a separate space is required to store the molded products before processing. There were other inconveniences.

The method for performing hot cutting work was also developed in 1983.
This method has been proposed in Publication No. 1365, etc., but this method is a cutting method for making billets from round bars that are continuously cast, and this method is generally not suitable for molded products that have complex shapes. It is difficult to say that it can be widely applied.

Melting and shearing are also known, but the cutting accuracy is low, and cutting in hot conditions can cause distortion of the molded product due to the cutting load, making secondary processing more complicated. There are also some inconveniences.

In view of these disadvantages of the prior art, the main object of the present invention is to provide a method for cutting a cast product that can shorten the cycle time and remove unnecessary parts without causing distortion. There is a particular thing.

[Structure of the Invention] <Means for Solving the Problems> According to the present invention, the present invention provides a cutting method for removing unnecessary parts such as runners from a released cast molded product, which comprises: A process of releasing the molded product when a shell-like solidified layer is formed on the surface layer of the casting in contact with the inner surface of the cavity after pouring, and a process of applying a straightening load while holding and fixing the product part of the molded product. This is achieved by providing a method for cutting a cast molded product, which includes the step of cutting off the unnecessary portion.

<Function> In this way, by releasing the mold early after pouring, the cycle time is shortened. Further, by performing the cutting while applying a hot straightening load, it is possible to avoid distortion in the molded product due to the cutting load due to residual stress generated during the casting process.

<Examples> Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows the overall layout of a casting molding apparatus to which the present invention is applied. This casting and forming apparatus has a mold clamping device 1 placed in the center, and on the left side there is a melting furnace 2 for raw metals such as cast iron or cast steel, and on the right side there are a sprue part, a runner part, etc. A cutting and discharging device 3 is provided for cutting the molded product and transporting it to the next process.

As shown in FIG. 2, the mold clamping device 1 includes:
A fixed platen 5 fixed on the base 4, a plurality of tie bars 6 fixed to the fixed platen 5 and extending in the horizontal direction, and a movable platen slidably provided along the tie bars 6. 7. A pair of mating molds 8a and 8b are attached to the mutually opposing inner surfaces of the fixed platen 5 and the movable platen 7, and the movable platen 7 is moved toward and away from the fixed platen 5 using a hydraulic device 9. By doing so, the molds 8a and 8b can be matched and opened.

A traveling rail 10 is laid above the mold clamping device 1 and the cutting and dispensing device 3 along the opening and closing direction of the molds 8a and 8b.
A transport device 11 that can run on its own is installed.

The conveying device 11 includes a gripping device 13 that is moved up and down by a lifting device 12 of a rack-and-pinion type or the like.
is provided on the lower end side, and the opened mold 8
The upper end of the molded product 14 taken out from inside a and 8b is grasped, pulled upward from the mold clamping device 1, and then automatically transferred to the cutting and dispensing device 3 in a suspended state. ing.

The molds 8a and 8b for casting the molded product are made of a material with high thermal conductivity, such as a copper alloy, and are equipped with a cooling water passage and a heater (not shown), so that the mold temperature can be controlled. It is done like this. As shown in Fig. 3, the cavity of the molded product 14, these molds 8a and 8b are used to simultaneously mold four camshafts, with a sprue 15 and a runner 16 extending vertically in the center. Further, a runner part 17 extending in the horizontal direction is formed at the lower part, and from this runner part 17 four product parts 18 which are to become camshafts are raised parallel to the runner 16, and furthermore, this product part Boasting water part 1 at the upper end of 18
9 is formed. And the sprue part 15 mentioned above
The lower side of the riser portion 19 is gripped by a gripping device 13.

As shown in FIG. 4, the cutting and discharging device 3 includes an electrically driven grindstone cutting machine 20, a pressing device 21 that holds and fixes the molded product 14 and applies a straightening load at the same time, and a press device 21 that applies a straightening load to the molded product after cutting. and a dispensing device 22 for taking out the mold from the pressing device 21, and are arranged adjacent to each other in series along an axis parallel to the parting surface of the mold in the mold clamping device 1.

The grindstone cutting machine 20 is placed on a slide base 24 mounted on a body frame 23, so that it cuts in a straight line along the left and right direction in FIG. 4, that is, along the axis parallel to the parting surface of the mold. It is provided with a pair of emery disks 25 that are slidable and parallel to each other with respect to the sliding axis (FIG. 5). This emery disk 25 is
For example, it is pivotally supported by the free end of an arm 26 that is pivotably supported so as to be able to swing vertically by hydraulic drive, and is driven by a belt by an electric motor 27 mounted on the base end side of the arm 26. Further, as a driving source for moving the slide base 24 described above,
For example, a hydraulic cylinder or an electrically driven screw device is used, and an accurate stopping position can be arbitrarily set.

As shown in FIGS. 5 and 6, the pressing device 21 is pivotally supported on the body frame 23 so as to be rotatable about an axis parallel to the parting surface of the mold, and is mounted at an appropriate position on the body frame 23. A trunnion-supported pneumatic cylinder 28 selectively rotates the cylinder between vertical and horizontal positions.

This pressing device 21 is provided with a pair of frame plates 30 integrally and parallel to the rotating shaft 29 . This frame plate 30 is open at its center and has a press jig 31 inside.

The press jig 31 includes a pair of fixing plates 32 that are integrally fixed with the frame plate 30 between the inner surfaces of the frame plate 30.
a, 32b, and a movable plate 35 that is supported by a hydraulic cylinder 33 and a guide bar 34 provided on one fixed plate 32b and can be displaced between both fixed plates 32a, 32b in parallel to these fixed plates. There is. These movable plates 35 and the other fixed plate 3
A plurality of V blocks 36 are erected on the mutually opposing inner surfaces of the molded product 14 so as to press and hold key points on the axis of the molded product 14 from the diametrical direction, with their ends facing each other.

This V block 36 is provided at a position corresponding to the bearing portion of the camshaft shown by reference symbol P1 in FIG. Manufactured with precision.

The dispensing device 22 includes a fork arm 37 that is pneumatically driven and capable of reciprocating in the left-right direction in FIG. 4. This fork arm 37 is
It can be inserted into and removed from the inside of the press jig 31 from between the edges of the vertical V-blocks 36, and a recess 38 is formed in its upper edge to receive the molded product 14.

Next, the operation procedure of the above embodiment will be explained.

When the molten metal is injected into the cavity of the mold, since the thermal conductivity of the molds 8a and 8b is extremely high,
The molten metal in contact with the inner surface of the cavity cools rapidly and immediately begins to solidify.

After pouring, the mold is opened when the surface layer of the molded product has solidified. At this time, by operating the ejector device 39b provided on the movable platen 7 side, only the mold 8b on the movable platen 7 side is opened. The molded product 14 is released from the mold, and the molded product 14 is left in the mold 8a on the fixed platen 5 side (FIG. 2).

Once the mold is opened, the lifting device 12 lowers the gripping device 13 and opens the sprue 15 and riser 19.
The gripping device 13 is moved horizontally so as to face the.

In this state, the ejector device 39 on the fixed platen 5 side
When actuating a, the molded product 14 is extruded from the mold 8a and is gripped by the gripping device 13.

Once the molded product 14 is gripped by the gripping device 13, the lifting device 12 is raised to pull the molded product 14 above the mold clamping device 1, and the molded product 14 is moved toward the pressing device 21 by the conveying device 11. transport.

The pressing device 21 opens the movable plate 35 and presses the frame plate 30.
The device is on standby with its opening surface facing up and down (the state shown on the left side of the center line C in FIG. 4).

Here, the lifting device 12 is lowered, and the V block 3
The molded product 14 is inserted between the six ends, and the molded product 14
The movable plate 35 is closed with the ends of each V block 36 aligned with the bearings P1, and the molded product 14 is inserted between both V blocks 36 to apply a correction load.

After releasing the molded product 14, the gripping device 13 rises again and moves backward toward the mold clamping device 1.

Next, the pressing device 21 is rotated 90 degrees, and the molded product 1 is
4 in the horizontal direction (to the right of the center line C in FIG. 4 and in the state shown in FIG. 5).

From this point, the grindstone cutting machine 20 is advanced, and first the fourth
In order to cut the two pieces on the right side in the figure, use the arm 26.
is tilted downward to press the emery disk 25 against the product section 18. As a result, the product portion 18 is cut along the line L1 to L2 shown in FIG.

Once the cutting is complete, remove the emery disk 25
After returning to the upper side, the grindstone cutting machine 20 is moved backward, and the two pieces on the left side are cut in the same manner as above (line L3 to L4 in FIG. 3). At this time, the feeder part 19 is separated from the product part 18, passes through the pressing device 21 and the chute 40a, 40b attached to the body frame 23, and falls into the bucket 41 placed on the side of the frame. In addition, the runner part 17 and the oil port part 15
remains in the press jig 31 together with the product part 18 in a state where it has been clamped by the V block 36.

When all cutting is completed, the grindstone cutting machine 20
is returned to its original position, and then the fork arm 37 is inserted between the V blocks 36. When the movable plate 35 is moved downward in this state, the runner part 17 including the product part 18 and the oil port part 15, which were on the V block 36 of the movable plate 35, is moved into the recess 38 on the fork arm 37. It will be transferred. Then, by moving the fork arm 37 backward, the molded product 14 that has been cut is extracted from the pressing device 21.

During the above-described series of steps, the molded product 14 is sufficiently cooled, and is pressed with a press jig 31 to remove unnecessary parts without causing distortion, and is removed manually from above the fork arm 37 or separately. It is sent to the next machining process by a transfer device.

[Effects of the Invention] As described above, according to the present invention, by releasing the mold early after pouring the molten metal, the casting cycle time can be shortened and production efficiency can be increased. Moreover,
Since the cutting operation is performed while applying a straightening load to the cast molded product, there is no worry that the molded product will be distorted, so it is possible to obtain a high-precision molded product and reduce secondary processing costs. This has a great effect on reducing manufacturing costs.

[Brief explanation of the drawing]

FIG. 1 is an overall layout diagram of a casting molding apparatus to which the present invention is applied. FIG. 2 is a side view of the mold clamping device portion. FIG. 3 is a partial end view of a mold for a molded article. FIG. 4 is a front view of the cutting and dispensing device. FIG. 5 is a partially cutaway side view taken along line V-V in FIG. 4. FIG. 6 is a partial plan view of the pressing device. 1... Mold clamping device, 2... Melting furnace, 3... Cutting and discharging device, 4... Base, 5... Fixed plate, 6
...Tie bar, 7...Movable plate, 8a, 8b...Matching mold, 9...Hydraulic device, 10...Traveling rail,
11... Conveyance device, 12... Lifting device, 13...
Gripping device, 14... Molded product, 15... Sprue part, 1
6... runner, 17... runner section, 18... product section, 19... riser section, 20... grindstone cutting machine, 2
1... Pressing device, 22... Dispensing device, 23...
...Aircraft frame, 24...Slide base, 25
...Emery disc, 26...Arm, 27...
...Electric motor, 28...Pneumatic cylinder, 29...Rotation shaft, 30...Frame plate, 31...Press jig, 32
a, 32b... Fixed plate, 33... Hydraulic cylinder,
34... Guide bar, 35... Movable plate, 36...
V block, 37...Fork arm, 38...
Hollow, 39a, 39b... Ejector device, 40
a, 40b...Shoot, 41...Bucket.

Claims (1)

[Claims] 1. A cutting method for removing unnecessary parts such as runners from a released cast product, in which a shell-like solidified layer is formed on the surface layer of the casting in contact with the inner surface of the cavity after pouring. Casting comprising the steps of: releasing the molded product at the stage where the molded product has been molded; and removing the unnecessary portion while holding and fixing the product part of the molded product and applying a correction load. How to cut the item.