JPH031454Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention is a method for supplying multiple types of powder used for molding a multilayer molded body in which layers of different types of powder form multiple layers in the radial direction in the cross section. This invention relates to a powder supply device.

[Conventional technology]

Conventionally, a technique in which a partition plate is provided in a powder box of a powder supply device for producing a multilayer compact is disclosed, for example, in Japanese Patent Publication No. 56-20120.

[Problem that the invention attempts to solve]

However, according to this method, there is a problem that mixing of adjacent powders that should constitute a multilayer cannot be avoided.

Therefore, the patent application filed earlier by the applicant in 1982-
According to the method for forming a multi-layer molded body described in No. 113485 entitled ``Method for forming a multi-layer sintered member'', a method was devised in which a plurality of powder boxes were provided individually and each powder box was operated separately.

However, in this case, a problem arises in that the number of devices for operating the powder boxes is equal to the number of layers required, making the entire device complicated.

In addition, in order to prevent the molded powder from deforming, it is necessary to lower the upper punch during preforming of the first layer, which poses a problem in that the operation of the press becomes complicated.

Therefore, an object of the present invention is to prevent the mixing of foreign powder that should constitute a multilayer, and to simplify the entire device and operation by using a common device for operating the powder box.

[Means for solving problems]

Therefore, the powder supply device for multi-layer compacts according to the present invention is characterized in that there is no need to lower the upper punch for preforming, and that foreign powder does not get mixed into the plurality of powder boxes. That is.

Specifically, in a powder supply device used for molding a molded part with multiple layers in the radial direction, the number of powder boxes required for multi-layer molding is continuously provided in a row on a die holder, and these powder boxes are In between, a flat part for preforming the compacted powder, and a powder suction part for removing powder remaining on the sliding surface of the powder box are provided on this flat part, and the powder box and the flat part A drive mechanism is provided to reciprocate along the arrangement direction.

[Effect]

The operation of the present invention having the above configuration will be explained by taking as an example the case of molding a two-layer molded product. First, the powder box is advanced toward the mold on the die holder by the drive mechanism.

When the first powder box reaches the center of the mold, it stops and is filled with the first powder.

When the filling of the first powder is completed, the flat part then retreats and passes over it. At this time, the first powder is compressed and preformed.

Furthermore, when the first powder box moves backward, the powder suction section sucks and removes the first powder remaining on the die.

The second powder box then moves back until it reaches the center of the mold and stops again, where it is filled with a second powder.

When filling of the second powder is completed, the second powder box is retreated to the retreat end.

Next, the upper punch is lowered to press and mold the first and second powders simultaneously.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail based on the drawings.

Fig. 1 is a plan view showing a schematic configuration of a powder supply device for multilayer molded bodies according to the present invention, Fig. 2 is a cross-sectional view taken along the - line in Fig. 1, and Fig. 3 is a powder leakage prevention mechanism. 4 is a front view of the multilayer molded body, and FIG. 5 is a sectional view taken along the - line in FIG. 4.
FIG. 6 is an operational diagram of the powder supply device showing the manufacturing process of the multilayer molded body.

The powder supply device 1 includes a die holder 2, a powder box holder 3, a cylinder 5, a guide 6, and a holder 7.
It consists of a limit switch 8.

The die holder 2 has a flat upper surface. A die 22 is fitted on the same plane as the upper surface of the die holder 2. The die 22 has a circular upper surface.

A lower outer punch 24 and a lower inner punch 2 are placed concentrically inside this die 22.
6. The core supporter 28 is fitted. 29
is a core rod.

The powder box holder 3 is placed on the upper surface of the die holder 2. A cylinder 5 is attached to the powder box holder 3 with a plate 39 interposed therebetween, and when the cylinder 5 is driven, the powder box holder 3 can slide on the upper surface of the die holder 2 in the front and back direction (left and right in FIG. 1). has been done.

The powder boxes 32, 33 are attached to the front and rear of the powder box holder 3 by plates 34, 39. On the lower surface of the powder box holder 3 located between the powder boxes 32 and 33, there is a flat part 35 that functions as an upper punch during preforming.
is formed. The flat portion 35 is in close contact with the upper surface of the die holder 2.

Furthermore, a powder suction section 36 that communicates with the flat surface section 35 is provided approximately at the center of the powder box holder 3 . The powder suction unit 36 is connected to a suction device (not shown) through a hose 362.

The powder box 32 is held by a retainer section 39 formed inside the arm section 38 of the powder box holder 3, as shown in FIG.

In this case, a small gap may be provided between the retainer portion 39 and the retainer receiving portion 322 of the powder box 32. If this gap is too small, it will cause burn-in,
If it is too large, it will cause powder leakage, so 0.05 to 0.15 mm.
is preferred.

The powder box 33 is also held in the same structure as the powder box 32.

The guide 6 is for preventing the entire powder box holder 3 from lifting up, and is attached to the die holder 2 by a pin 372.

This guide 6 has a gap of 1 to 2 mm between the pin 372 and the pin hole 373, and a gap of 0.02 to 0.1 mm between the upper surface of the guide 6 and the lower surface of the flange of the pin.
Since it is attached with a minute gap of mm, it is possible to slide in a direction intersecting the direction of movement of the powder boxes 32 and 33.

Further, a tapered portion 62 corresponding to the tapered portion 382 provided on the powder box holder 3 is provided inside the guide 6. Note that the angle of the tapered portions 382 and 62 is 7° or less.

As a result, the powder box holder 3 moves forward and backward on the die holder 2 while sliding on the guide 6 and these tapered portions 382 and 62.

The holder 7 is for holding the spring 43 in a compressed state in order to press down the guide 6 from the outside, and is fixed onto the die holder 2 by bolting (not shown).

As a result, the tapered portion 62 becomes the tapered portion 38.
During preforming, the powder box holder 3 is pressed onto the die holder 2 by the force of the spring 43 via the spring 43.
Even when pressurized upward by the lower inner punch 26, the gap between the lower surface of the powder box holder 3 and the upper surface of the die 22 can be maintained close to zero.

In this way, the powder box holder 3
3 and the cylinder 5, the die 22 is slid on the upper surface of the die 22 in a state where lifting is suppressed by the guide 6.

The limit switch 8 is for controlling the forward, backward, and stopping operations of the powder box holder 3, and is fixed to the die holder 2 by a mounting plate 82. Further, 84 is a dog for operating the limit switch 8, and the stay 84 extends from the powder box holder 3.
It is attached to 6.

Here, a mechanism for preventing powder leakage caused by a gap between the retainer portion 39 formed inside the arm portion 38 of the powder box holder 3 and the retainer receiving portion 322 of the powder box 32 will be described.

A retainer portion 384 is formed inside the arm portion 38, and a through hole 386 is formed in the retainer portion 384. Further, a flange portion 324 is formed on the outside of the powder box 32, and a through hole 326 is formed in this flange portion 324.

Guide pins 42 are loosely fitted into these through holes 386 and 326. Further, a compression spring 44 is interposed between the retainer portion 384 and the flange portion 324. 46 is a stopper for the compression spring 44.

Since the arm portion 38 is prevented from floating up by the guide 6, the powder box 32 is pressed against the upper surface of the die 22 by the compression spring 44, thereby preventing powder leakage.

At this time, if a dust seal or the like is attached to the bottom surface of the powder box 32, the effect of preventing powder leakage can be further improved.

Although the powder box 32 has been explained above as an example, the powder box 3
You can do the same for 3.

The operation of the embodiment according to the above configuration will be explained by taking as an example the case where a two-layer molded body is molded. First, before starting the molding operation, the molded body is in the original position shown in FIG. 6A.

From this state, when the cylinder 5 is driven, the powder box holder 3 moves forward. In this case, the powder box 32 passes through the die 22 and stops when the powder box 33 comes to the center of the die 22. At this time, dice 22,
Lower outer punch 24 and lower inner punch 2
6 maintains the original position.

Next, when the lower ram (not shown) rises, the die 22 and lower outer punch 24 rise,
A cavity is formed above the lower inner punch 26, and powder 330 is sucked in and filled. FIG. 6B shows this state.

Next, the powder box holder 3 is moved backward while the die 22, lower outer punch 24, and lower inner punch 26 are kept in the state B, and the flat part 35 is attached to the die 2.
It stops when it comes to the center of 2.

When the lower outer punch 24 rises from this state, the powder 330 sandwiched between the flat portion 35 and the lower outer punch 24 is preformed to a predetermined thickness.
This state is shown in FIG. 6C.

Next, the powder box holder 3 retreats while the die 22, lower outer punch 24, and lower inner punch 26 maintain the state shown in FIG. 6C. At this time, the powder suction unit 36 retreats while sucking the powder remaining on the die 22, in this case the powder 330.

Then, when the powder box 32 comes to the center of the die 22, it stops. From this state, the lower outer punch 24 descends and is filled with powder 320. This state is shown in FIG. 6D.

Next, the powder box holder 3 retreats to the retreating end shown in FIG. 6A and stops. Then, the upper punch 12 descends to pressure-form the powder 330 and the powder 320 at the same time.

Then, the lower ram is further lowered to extract the molded body, and the upper ram is raised to remove the upper punch and complete the molding process.

The molded body thus formed is shown in FIGS. 4 and 5.

Although the present invention has been described above based on specific embodiments, it is not limited thereto, and those skilled in the art can think of various other embodiments that can be implemented within the scope of the claims for utility model registration. It will be done. For example, the drive mechanism may be a motor instead of a cylinder.

[Effect of idea]

As explained above, the powder supply device for multi-layer compacts according to the present invention does not require lowering the upper punch for preforming, and has a structure that prevents foreign powder from getting mixed into the plurality of powder boxes. This has excellent effects in that it is possible to prevent foreign powder from entering the multi-layer structure, and to simplify the entire device and operation by using a common device for operating the powder box.

[Brief explanation of drawings]

Fig. 1 is a plan view showing a schematic configuration of a powder supply device for multi-layer compacts according to the present invention, Fig. 2 is a sectional view taken along the - line in Fig. 1, and Fig. 3 shows a powder leakage prevention mechanism. 4 is a front view of the multilayer molded body,
Figure 5 is a sectional view taken along the - line in Figure 4;
The figure is an operational diagram of the powder supply device showing the manufacturing process of a multilayer molded body. 1...Powder supply device, 2...Die holder, 5...
...Cylinder, 32, 33...Powder box, 35...Plane part, 36...Powder suction part.

Claims (1)

[Scope of utility model registration request] In a powder feeding device used for molding a molded part with multiple layers in the radial direction, powder boxes of the number required for multi-layer molding are successively provided in a row on a die holder, and between the powder boxes, molded powder is supplied. a flat part for preforming the powder box; a powder suction part for removing powder remaining on the sliding surface of the powder box on the flat part; A powder supply device for a multilayer molded body, characterized in that it is provided with a drive mechanism for reciprocating movement.