JPH0364403A - Apparatus and method for forming member for sintering having spiral hollow hole - Google Patents

Abstract

PURPOSE:To easily form the subject member for sintering at a low cast by retreating a needle from a die member after feeding under pressurizing and filling up plastic kneaded material into a forming device composed of a mouth piece having the needle and the die as dividable, with spiral pin freely inserted. CONSTITUTION:The forming apparatus for sintering member 8 is constituted of the mouth piece 4 having the needle 2 and the die 3 as dividable, with the spiral pin 1 freely inserted. An extruding machine 7 composed of a cylinder 71 and screw 72 is driven and the plastic kneaded body is pushed and filled up in the die 3. When the filling-up is completed, the extruding machine 7 is stopped and needle feeding mechanism 5 is driven and the needle 2 is rotated and at the same time, this is retreated and the die 3 is slidingly moved at the joining face with the mouth piece 4 to shear a material to be formed. Successively, the die 3 is taken out and divided, and the formed body 8 is taken out, dried and the de-binder is executed to feed this into sintering process. By this method, the sintering member 8 having spiral hollow hole is easily obtd. at a low cost.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention relates to the molding of a sintered dissection having a spiral hollow hole, typified by a so-called oil hole drill, which has a hole through which cutting oil passes. Related to apparatus and molding method.

[Conventional technology]

In the field of materials such as metal materials, cemented carbide, and ceramics,
So-called hollow products, which have a hole inside the material, are universally available. In the metal materials field, hollow products are manufactured using methods such as machining, hot extrusion, and welding, while in the cemented carbide and ceramics fields, extrusion molding methods are used to extrude hollow products from dies in a plastic state after kneading. Attempts are being made to obtain timber.

Among hollow products, hollow products typified by oil holes (Q-drills) have multiple hollow holes and must be spirally twisted, making manufacturing difficult and expensive.

Of the gold B-grade materials, the material for drills with oil holes manufactured from high-speed tool steel, which is normally ingotten, is made by drilling two straight holes with a drill, pulling them out to the desired hole diameter, and then drilling the hollow holes to the specified lead. It is manufactured by mechanically twisting it so that it becomes .

When manufacturing from powder metallurgy materials, a material with straight holes is obtained by extrusion molding, and then mechanically twisted in the same way as ordinary melted material to obtain a base material for drills with spiral hollow holes. ing.

Furthermore, in the field of cemented carbide, Japanese Patent Application Laid-Open No. 61-227101
JP-A No. 62-240701 discloses a molding machine □ and a molding method for a drill element having a spiral hollow hole by imparting twist at the same time as extrusion.

In the field of powder metallurgy, the applicant has developed a threaded extrusion device j14 and an extrusion method for sintered members that eliminate the mechanical twisting step and provide spiral hollow holes immediately after molding, and have published a 1. No.-96305, patent application 1986-18
The application was filed as No. 2994.

[Invention or problem to be solved]

The above-mentioned forming method, in which a material with straight hollow holes is obtained and then mechanically twisted to form open hollow holes, requires an expensive twisting device and slows down the manufacturing process. There is a problem that the cost increases because there are many more.

In addition, with extrusion molding machines and molding methods that create spiral hollow holes while applying twist at the same time as extrusion, handling is difficult because the molded material in a green state immediately after extrusion is extruded while rotating. The problem is that it is difficult and has low workability.

Further, in all conventional molding methods, the pin for providing the hollow hole is supported in a cantilever manner, and therefore, there is a problem in that excessive stress acts on the pin, causing early breakage or deformation of the pin.

In view of the above-mentioned problems, the present invention provides an apparatus and a method for forming a sintering member having spiral hollow holes using a simple device and at low cost when producing a sintered assembly using a powder metallurgy method. With the goal.

The sintered member in the present invention refers to a material for a sintered member that is manufactured through a sintering process after molding, and is also generally referred to as green.

[Means to solve the problem]

The molding device of the present invention is provided in front of a feed supply device that sends out a plastic kneaded material, which is a material to be molded, in the direction of movement of the material to be molded, and has a conical inner diameter surface, and has a centering piece in the center thereof. A cap having a supported needle, which is provided in front of the cap and can be divided into a plurality of parts, and a helical pin fixed to the end surface of the needle is loosely fitted into the center of the inner diameter of the cap, and has a cap on the end surface. A sintering device having a spiral hollow hole, comprising a mold member and a needle rotation feeding mechanism supported by a support member on the end face of the mouthpiece, which moves the spiral bottle forward and backward while rotating together with the needle. This is a molding device for parts for use.

Then, the mold member into which the helical pin is loosely fitted has a helical protrusion on the inner diameter surface, and a pin hole having the same lead as the helical pin is provided in the cap installed on the end face of the mold member. , the tip of a spiral pin is inserted into the pin hole.

Furthermore, the molding method of the present invention includes a plastic kneading process in which a mixture of one or more metal powders or alloy powders and a binder consisting of at least one of a plasticizer, a binder, a dispersant, a lubricant, and a solvent are mixed and kneaded. Using a sintering member forming device consisting of a die having a needle and a divisible mold member into which a spiral pin is loosely fitted, the body is passed through the die by the supply pressure of the material supply device. The mold member is compressed to fill the space in the mold member, the helical pin is moved backward from the mold member by the operation of a needle rotation mechanism, and then the mold member is divided to form a molded body. This is a method for forming a sintering member having a spiral hollow hole, which is characterized in that the member is removed.

In the present invention, the helical pin that is loosely fitted into the center of the inner diameter of the mold member is fixed to the tip end surface of the needle, and moves forward and backward together with the needle by the operation of the needle rotation feed mechanism, and is connected to the mold member. It moves back and forth while rotating between the caps.

After the plastic kneaded material supplied from the auxiliary material supply device is filled, the needle is rotated and retracted in accordance with the torsion lead of the helical pin, and the helical pin is retracted to the position of the metal. A spiral hollow hole is obtained in the molding phase. After the spiral pin retreats, the mold member is removed from the die and disassembled to take out the molded material.

〔Example〕

Next, the present invention will be explained in detail based on one embodiment.

FIG. 1 is a sectional view showing an embodiment of the molding apparatus and molding method according to the present invention.

In this example, an extruder consisting of a cylinder 7e and a screw 72 was used as the material supply device. The needle feeding mechanism 5 is housed in an intermediate cylinder 6 which is a support member, and this intermediate cylinder 6 is attached to the tip of the cylinder.

The needle feeding mechanism 5 transfers the rotational force of the motor 51 to the transmission 5.
2. The transmission is transmitted to the feed screw 56 via the reducer 53 to operate the tie bar 57, and at the same time several combined gears 54
We have manufactured a structure in which the signal is transmitted to the gear shaft via the gear shaft.

The needle 2 is fixed to the end of a gear shaft and has a spiral pin 1 fixed to its tip, and is fed through a tie bar 57 by a feed screw 56 controlled in accordance with the torsional lead of the spiral pin 1. It is given a rotation (=j) by the gear shaft 55, and moves forward and backward.

A cap 4 having a conical inner diameter surface is installed at one end of the intermediate cylinder 6, and the needle 2 described above is arranged so as to be located at the center of the inner diameter. Furthermore, it is installed in a loosely fitted state at the center of the inner diameter of the die 3, which is a mold member that can be divided into a plurality of pieces, on the tip surface of the mouthpiece 4.

The rotational speed and feeding speed of the needle 2 can be adjusted to match the lead of the helical pin 1 by replacing the gear 54 with an arbitrary diameter.

Next, using the above-mentioned apparatus, 0.1.45% of Al5I T15 equivalent, 0.37% of Si, Mn
O, 39%, Cr 4.01%, W 12.
18%, Mo 1.02%, V 4.65%, Go 4
．． A water-atomized prealloy powder consisting of 77% iron and unavoidable impurities was used to form a bar material for an oil hole drill having a spiral hollow hole.

The average particle size of the powder was 44 μm. This was dry-pulverized in an attritor to give an average particle size of 17 μm.

4 parts of methyl cellulose per 100 parts of the weight of this powder.
A plastic kneaded body was prepared by mixing and kneading 5 parts of water, 2 parts of microtalista line wax, 1 part of stearic acid emulsion, and 1 part of glycerin.

This crosstalk body is located at the position where needle 2 is shown (forward position).
By fixing the helical pin ↓ inside the die 3, the extruder 7 of the device was driven to fill the inside of the die 3. After filling, the extruder 7 is stopped, the needle 2 is rotated and simultaneously retreated to the left in the figure 2, the die 3 is slid on the joint surface with the nozzle 4 to shear the material to be formed, and the die was removed and a molded body as shown in Fig. 3 was taken out. When the molded body was taken out, the work could be done without any problems such as handling.

Thereafter, the die 3 is assembled, the needle and the spiral pin are placed on standby at the predetermined positions shown, and the above molding cycle is repeated. The shaped sintering member (green) is dried, the binder is removed, and then sent to the sintering process.

FIG. 2 is a diagram showing another embodiment of the present invention.

A helical protrusion 32 is provided on the inner diameter surface of the die 3, and a pin hole having the same lead as the helical pin 1 is provided in the cap 31, and the tip of the helical pin 1 is inserted into this pin hole.

By adopting the structure as described in Section 2, it was possible to form a spiral groove on the outer periphery of the molded body, making it easier to shape the drill. Furthermore, since the spiral pin 1 can be supported at both ends, the life of the pin can be improved.

In this embodiment, a structure in which the cylinder and the die are arranged in series has been described, but depending on the case, a structure in which a cylinder serving as a material supply device is installed on the side of the die may also be adopted.

〔Effect of the invention〕

As described above, the present invention eliminates the need for an expensive twisting device because the twisting process for forming a straight material into a spiral shape is omitted. According to the present invention, a member having a spiral hollow hole can be manufactured with only one step of extrusion molding of a material to be formed, so it is easy to manufacture a sintered member having a spiral hollow hole, such as a drill with a hole. This invention can be provided at low cost and is industrially very effective.

[Brief explanation of drawings]

FIG. 1 shows 1! according to the present invention! A cross-sectional view showing one embodiment of a rod-shaped extrusion molding device having spiral-shaped hollow holes, FIG. 2 is a cross-sectional view showing another embodiment according to the present invention, and FIG. 3 is a cross-sectional view showing the use of the molding device of the present invention. It is a figure which shows an example of the molded object shape|molded. 1: Spiral pin, 2: Needle, 3: Die, 31: Cap, 32: Protrusion, 4: Base, 5: Needle feed mechanism, 5 ■: Motor, 52: Transmission, 53: Reducer, 54:
Gear, 55: Gear shaft, 56: Feed screw, 57: Tie bar,
58: centering piece, 6: intermediate cylinder, 7: extruder,
71 Nijirinda, 1 Kakomasu style: 16゛hi Shinny F゛' / Shidaisky 5.7f. Yasu Kiguchi AΣ 2 52 Mugisoku 534 E Mu 54 Teeth Hayabusa 55 Rotary Car 56 57 Fiber 58t Yukunoshiku° EO-S 6 + Ransuji I Kami Izumi 71〉 Rini Nu 72 Nukukuyu 8 Floor shape Ikiku - ＼ 沫 - L1″+1＼ qノU)

Claims (1)

[Scope of Claims] 1. A material feeding device that feeds out a plastic kneaded material, which is a material to be formed, is provided at the front in the direction of movement of the material to be formed, has a conical inner diameter surface, and is supported by a centering piece at its center. A mold that is provided in front of the mouthpiece and can be divided into a plurality of pieces, has a spiral pin fixed to the end face of the needle loosely fitted in the center of the inner diameter of the mouthpiece, and has a cap on the end face. A sintering member having a spiral hollow hole, the member comprising a needle rotation feed mechanism supported by a support member on the end face of the mouthpiece, which moves the spiral pin forward and backward while rotating together with the needle. molding equipment. 2. The apparatus for molding a sintering member having a spiral hollow hole according to claim 1, wherein the mold member into which the spiral pin is loosely fitted has a spiral projection on its inner diameter surface. 3. A cap installed on an end surface of a mold member is provided with a pin hole having the same lead as the helical pin, and the tip of the helical pin is inserted into the pin hole. 2. The apparatus for forming a sintering member having a spiral hollow hole according to item 2. 4 A plastic kneaded body obtained by mixing and kneading a mixture of one or more metal powders or alloy powders and a binder consisting of at least one of a plasticizer, a binder, a dispersant, a lubricant, and a solvent is passed through a nozzle having a needle. Using a molding device for a sintering member consisting of a splittable mold member into which a spiral pin is loosely fitted, the material is compressed by passing through the die by the supply pressure of the material supply device, and the mold member is compressed by passing through the die. A spiral device that fills a space in a member, moves the helical pin backward from the mold member by operating a needle rotation mechanism, and then divides the mold member and takes out the molded product. A method for forming a sintering member having hollow holes of the shape.