JPH10263895A - Formed article carrying-out device in powder molding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry out a formed article of an easily falling shape such as a slender cylindrical shape from a powder molding machine without being overturned. SOLUTION: A decompression chamber 80 and a support member 83 having a recess to be adapted to the shape of a formed article are provided on a forward part of a feeder 60 reciprocating on a die plate 51, and the recess is communicated with the decompression chamber through a suction port 82. The formed article is sucked to the recess through evacuation of the decompression chamber, and moved above a chute 70. When suction is stopped while the feeder is retracted, the formed article is transferred to the chute in a posture with its lower end at the tip, and slides down.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for transferring a molded product having a shape such as a cylinder which is easy to fall down from a powder molding machine without damaging it, and is mainly used in the field of powder metallurgy. It can be applied to powder molded products in the field.

[0002]

2. Description of the Related Art Powder compaction in powder metallurgy is briefly described by taking a sintered gear as an example (see FIG. 4). A die 10 for forming a gear tooth profile, a lower punch 20, and a core rod 30 for forming a shaft hole of the gear are used. By compressing the raw material powder filled in the die cavity to be formed between the upper punch 40 and the lower punch 20, a product (molded product) having a desired shape can be obtained.

In molding powder, the die and the lower punch move up and down relatively in order to make the green compact density uniform. Depending on which of them is fixed to the press, the method of assembling the die set is different. Fixed and movable lower punch types are generally classified into lower punch fixed and die movable types, which are generally called withdrawal die sets. Both types have no difference in the basic principle of powder molding.

FIG. 4 shows one cycle of powder molding. In practice, the latter method is often used, but the drawing shows the former case of the fixed die and the movable lower punch, due to space limitations. (A) of the figure shows a state in which the powder filled in the die 10 is compression-molded, and the upper punch 40 is raised from the figure, and then the lower punch 20 is raised to the upper surface of the die plate 51. The molded article is extruded from the die as in

[0005] Next, when the feeder 60 of the raw material powder is moved from the standby position onto the die, the molded product is pushed away from the die by the leading edge of the feeder to the right side of the die plate. At the same time, the lower punch 20 is lowered to a predetermined filling depth (C to D), the powder is filled in the die, and the next compression molding is performed. During this repetition, the molded product displaced from the top of the die sequentially moves to the right end of the die plate, and eventually slides down on the chute 70 and is carried out of the powder molding machine. A flexible tube and a raw material hopper are connected to the powder supply port 61 of the feeder 60, and a drive source such as hydraulic pressure is connected to the drive rod 62. In other figures, the drive rod 62 is left to indicate the direction of the feeder, but the powder supply port may be omitted due to space limitations.

[0006]

Such a conventional carrying-out means is used when the object to be molded has a shape such that the bottom area is large for its height and hard to fall down, such as a gear illustrated in FIG. Although there is no problem, in the case of elongated molded products such as oil-impregnated bearings in (a), it is easy to overturn when pushing away from the die with the feeder and then moving to the chute. May leave latent cracks. For this reason, there has been a demand for a means capable of carrying out a molded product having a shape that easily falls without falling over.

[0007]

According to the present invention, a reciprocating stroke of the feeder 60 is extended to the tip of the die plate, and a depressurizing chamber 80 is provided at the front of the feeder, and a support having a recess adapted to the shape of the molded product. A member 83 is provided so that the recess communicates with the decompression chamber through an intake hole 82, and the molded product is moved to a position above the chute 70 in a state where the molded product is sucked into the recess of the support member 83, thereby eliminating the opportunity to fall on the die plate. It is. Hereinafter, the present invention will be described in detail with reference to one embodiment shown in FIGS.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, a feeder 60 is provided with a decompression chamber 80 by dividing a front portion thereof. In front of the decompression chamber, a shape of a molded product as shown in FIG. A support member 83 having a matching recess is provided. The depression of the support member and the decompression chamber communicate with each other via an intake hole 82, and an exhaust device (not shown) is connected to an exhaust port 81 of the decompression chamber. It is appropriate that the diameter of the recess of the support member is slightly larger than the diameter of the molded product.

When the feeder 60 starts to move forward (from the left standby position) as shown in (a), the molded product extruded from the die (not shown) is caught and adsorbed in the recess of the support member 83, and the chute 70 side Go to And like (b)
The lower end of the molded product is separated from the die plate 51 and the chute 7
Stop the feeder where it floats above zero. The exhaust from the decompression chamber is adjusted to such an extent that the molded product does not slip down in this state.

Next, when the exhaust is stopped while the feeder 60 is retracted, the molded product is released by being restrained by suction and slips down, the lower end rides on the chute 70, the upper end falls down to the feeder side by inertia, and Is safely slipped down the chute 70 in the posture in which. Thus, when the feeder 60 returns to the original position, one cycle from molding to unloading is completed, but it is conventional that the die is filled with powder while the feeder reciprocates.

The decompression chamber 80 may be integrated with the feeder 60, or may be separately formed and attached as shown in FIG. Similarly, the support member 83 may be integrated with the decompression chamber 80, but it is economically preferable that the decompression chamber 80 is used for general purpose and prepared individually according to the shape and size of the molded product. In this case, the suction holes 82 on the support member side can be appropriately set according to the molded product to be handled, both in terms of position and number, while the suction holes on the decompression chamber side can be formed as long holes and shared by each support member. It is more preferable that the support member is made of a cushioning material, since a shock to the molded product is prevented. Also, if grooves are formed in the chute 70 as shown in FIG. 2 (b) to match the shape of the molded product, the molded product can be sent to the next step in a certain direction.

Further, when a hole is provided at the bottom of the decompression chamber at a position where the hole comes off the die plate at the stop position of the feeder, the molded article is released from the restraint without stopping the exhaust from the decompression chamber at the stop position. Since it slides down on the chute, it is not necessary to provide an exhaust on / off control mechanism on the exhaust device side.

In the above-described embodiment, the flexible conduit from the exhaust device is piped to the ceiling of the decompression chamber 80.
0, and if the pressure inside the feeder is reduced to improve the flow of powder,
It can be used for adsorption.

[0014]

As described above in detail, according to the present invention, although the time required for one cycle is increased by the length of the stroke of the feeder as compared with the conventional one, the molded product having a shape that easily falls down is safely carried out without damaging it. Because of this, there is a great advantage that the yield of the molded product and the reliability of the product are significantly improved. Therefore, the present invention is particularly useful when manufacturing a severely-sintered component such as a valve guide of an automobile engine.

[Brief description of the drawings]

FIG. 1 is a drawing for explaining one embodiment of the present invention, relating to a molded product of FIG.

FIG. 2 is a view for explaining a detailed embodiment in one embodiment of the present invention.

FIG. 3 is a drawing illustrating the shape of a product (powder molded product).

FIG. 4 is a diagram illustrating the general principle of powder molding.

[Explanation of symbols]

10: die, 20: lower punch, 30: core rod, 40
... Upper punch 51 ... Die plate, 70 ... Chute 60 ... Feeder, 61 ... Powder supply port, 62 ... Drive rod 80 ... Decompression chamber, 81 ... Exhaust port, 82 ... Intake hole, 83 ... Support member.

Claims (1)

[Claims] 1. A powder molding machine configured to move a molded product extruded from a die to a chute 70 provided at an end of the die plate at a front edge of a feeder 60 reciprocating on a die plate 51. A decompression chamber 80 and a support member 83 having a recess adapted to be sucked in conformity with the shape of the molded article and communicating with the decompression chamber through an intake hole 82 are provided at the front portion of the mold 60, and the lower end of the molded article is separated from the die plate 51. A molded product unloading device in a powder molding machine, wherein the feeder 60 is configured to reciprocate to a position away from the molded product.