JPH0679798B2 - Mold clamping device for powder molding press - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a die clamping device for mounting an upper punch, a die and a lower punch in a powder molding press to respective support plates.

[Prior Art] A powder molding press machine presses and compresses powder to obtain a molded product. However, the upper punch, die, and lower punch that perform pressing are those that match the shape and size of the molded product. used.
Therefore, the upper punch, the die and the lower punch can be exchanged for the respective support plates.

FIG. 5 shows a conventional example for attaching the upper punch, die and lower punch to a powder molding press. Upper punch
The reference numeral 51 is mounted on the lower end surface of an upper punch plate 53 which is hung on the guide rod 52, the die 54 is fitted in the die plate 55, and the lower punch 56 is mounted on the upper surface of the fixed plate 57. The upper punch 51, the die 54 and the lower punch 56 are mounted by screwing bolts 61, 62 and 63 via clamp rings 58, 59 and 60, respectively. That is, first, the lower punch 56 is positioned on the fixed plate 57, and the bolt 63 is screwed into the clamp ring 60. The bolts 63 are normally screwed onto the clamp ring 60 in an amount of 4 to 6 screws on the same circumference, but the bolts 63 are tightened uniformly so that the lower punch 56 is not tilted. After mounting the lower punch 56, insert the die 54 into the upper part of the lower punch 56, position so that the insertion clearance is uniform around the lower punch 56, and tighten the clamp ring 59 evenly with the multiple bolts 62. The die 54 is attached to the die plate 55. Next, the upper punch 51 is inserted into the die 54, the upper punch plate 53 is lowered to engage the clamp ring 58 with the flange portion of the upper punch 51, and the bolts 61 are uniformly tightened. After the mounting of the upper punch 51, the die 54, and the lower punch 56 is completed as described above, the upper punch plate 53 is moved up and down to perform idle operation, and it is confirmed that there is no deviation or twisting.
When these are found, the bolts are re-tightened again to perform the centering work.

[Problems to be Solved by the Invention] Generally, in a powder molding press, the clearance between the upper punch and the die and between the die and the lower punch is about 0.010 to 0.015 mm, and if there is no uneven tightening, a clearance between them is required. Scratching and scoring will occur, resulting in a short smooth operation and shortened service life. Therefore, in the above-mentioned mounting work, it is necessary to tighten the bolts evenly and uniformly.
However, such tightening of bolts is performed by rotating the number of threads of precision bolts having a small pitch, which makes the work troublesome and requires a great deal of skill.

The present invention has been made in consideration of such circumstances, and by providing a clamp device that does not require bolting work,
This enables quick and easy mounting of the die and lower punch.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention relates to a die clamping device of a powder molding press machine for fastening an upper punch, a die and a lower punch to a support plate via a clamp ring. A cylinder is formed in the support plate in a donut shape centered on a clamped mold, and a plurality of piston rods are arranged at equal intervals on a concentric circle in the donut-shaped piston of the cylinder. The end of the rod is configured to engage with the clamp ring to apply a fastening force to the clamp ring, and the clamp ring is fastened and released by vertical movement of the piston.

[Embodiment] An embodiment of the present invention will be specifically described below with reference to FIGS. 1 to 3. FIG. 1 is a sectional view of a die set portion of a powder molding press to which an embodiment of the present invention is applied.
Although not shown, a press body portion is connected to this die set portion so that charging of powder, pressurization, extrusion of a molded product from a die, and removal of the molded product after extrusion are automatically performed. .

In FIG. 1, an upper punch plate 4 guided by a guide metal 3 is vertically movably attached to a guide rod 2 provided upright on a die plate 1. A T-shaped groove portion 5 is formed on the upper surface of the upper punch plate 4, and the groove portion 5
A T-shaped joint (not shown) of the upper ram of the press body is fitted and connected to the upper punch plate 4 for vertical movement and pressure forming. The die plate 1 is supported by a portion framed by a vertical rod 6 and a pull-down plate 7. This frame part is guided by the guide metal 8 and can be moved up and down, and the charge position, pressurizing position, and extrusion position of the powder are respectively positioned in relation to the operation of the press body part. There is.
The attachment to the press main body is performed by placing the fixing plate 9 on the bolster 10 of the press main body and fixing it with bolts or the like. For connection with the lower ram (not shown) of the press body portion, a T-shaped groove portion 11 is formed on the lower surface of the pull-down plate 7, and a T-shaped joint (not shown) of the lower ram is fitted into this groove portion 11. It can be done.

In such a pressing machine, the upper punch 12, the die 13 and the lower punch 14 for pressing the powder are fastened to the respective support plates. That is, the upper punch plate 4 is used for the upper punch.
It is fastened to the lower surface, the die 13 is fitted in the die plate 1, the lower punch 14 is fastened to the upper surface of the fixed plate 9, and the clamp device 20 is used for mounting each of them. Each clamp device 20 includes a clamp ring 21, a rod portion 22 and a piston rod 35. The clamp ring 21 presses the upper punch 12, the die 13, and the lower punch 14 against the upper punch plate 4, the die plate 1, and the fixed plate 9, which are supporting plates, respectively. This pressing causes the upper punch 12, the die 13, and the shoulder portions 12a, 13a, 14a to be formed on the outer peripheral surfaces of the lower punch 14,
This is performed by forming a contact portion 21a on each clamp ring 21 that contacts the shoulder portions 12a, 13a, 14a. The piston 35 is a cylinder 2 formed on each support plate 4, 1, 9.
It is inserted so that it moves up and down in the inside. The cylinder 23 and the piston 35 are formed in a donut shape, and the rod portion 22 has a plurality of four or six groups arranged at equal intervals on the same circumference of the support plates 4, 1, 9. The lower end or the upper end of the rod portion 22 is extended from the inside of the cylinder 23 to the outside, and a flange piece 24 is formed at the extended end, and the flange piece 24 is the clamp ring 21.
The clamp ring 21 to each support plate 4, 1, 9
It has a structure to be pressed against. Also, a spring 25 in which a plurality of disc springs are superposed is inserted in the cylinder 23 to urge the piston 35 in the clamping direction, and a hydraulic means 30 for supplying oil into the cylinder 23 on the opposite side of the spring 25. Are connected. This hydraulic means 30 corresponds to each support plate 4, 1, 9
The cylinder 23 includes valves 31, 32, 33 for switching oil supply and oil removal from the cylinder 23, and a hydraulic pump 34 connected to the valves 31, 32, 33. The hydraulic means 30 releases the clamp ring 21 from the clamped state. That is, when the hydraulic pump 34 is operated with the valves 31, 32, 33 open, oil is supplied into the cylinders 32 and the piston 35 slides in the anti-biasing direction of the spring 25, whereby Collar piece pressing the clamp ring 21
24 is released from the clamp ring 21, and the clamped state is released. It should be noted that such oil is supplied to each support plate 4, 1, 9
It is designed to be performed on all cylinders 23 at the same time.

2 and 3 are a plan view and a partial perspective view of the clamp ring 21, respectively. Upper punch 12, die 13 in the center
Alternatively, an insertion hole 21b into which the lower punch 14 is inserted is formed, and the same number of lock holes 2 as the rod portions 22 are formed on the outer peripheral side of the insertion hole 21b.
6 are formed. The lock hole 26 is the collar piece 24 of the rod portion 22.
Larger diameter part 26a larger than the smaller diameter part 26b smaller than the collar piece 24
It has a gourd shape in which and are connected in series. Therefore, the collar piece 24 of the rod portion 22 is inserted into the large diameter portion 26a of the lock hole 26 and rotated by a certain angle, so that the small diameter portion 26b of the lock hole 26 and the rod portion 22 are rotated.
The clamp ring 21 is prevented from coming off by aligning it with the flange piece 24, while the clamp ring 21 is removed by rotating the clamp ring 21 in the opposite direction from this state. Incidentally, 27 is an O-ring fitted in the piston 35.

According to the present embodiment as described above, the rod portion 2 protruding from each support plate 4, 1, 9 is inserted into the lock hole 26 of the clamp ring 21.
When the second collar portion 24 is inserted and the clamp ring 21 is rotated, the collar portion 24 engages with the clamp ring 21 to prevent the clamp ring 21 from coming off, and the spring 25 causes the collar portion 21 to come off.
Since the clamp ring 21 is biased in the clamping direction via 24, the upper punch 12, the die 13 and the lower punch 14 are fastened. Therefore, since it is not necessary to fasten the bolts while performing the centering work, the fastening work is extremely simplified and can be performed quickly.

FIG. 4 shows another embodiment of the present invention. The same parts as those in the above embodiment are designated by the same reference numerals, and the description thereof will be omitted. In this embodiment, the hydraulic means 30 is connected to the upper and lower chambers partitioned by the piston 35 without inserting a spring into the cylinder 23. Both the fastening and releasing of the clamp ring 21 are performed by hydraulic pressure, and a large actuating force can be obtained, so that it can be applied to a large-sized powder molding press.

Various modifications can be made in the present invention. A coil spring may be used instead of the disc spring, and air pressure may be used instead of hydraulic pressure.

[Effects of the Invention] As described above, according to the present invention, a cylinder is formed in a donut shape centered on a clamped die, and a plurality of piston rods are arranged at equal intervals on a concentric circle in the donut-shaped piston of the cylinder. Since the piston rings are arranged so that the clamp ring is fastened and released by the vertical movement of the piston, all the piston rods can be connected to the same piston and can be operated at the same time. You can hold them down at the same time. Therefore, even if the lower die and the die are fixed to each other, the lateral displacement does not occur, and the mounting can be performed with high accuracy.

Moreover, since the clamp ring is fastened and released by the vertical movement of the piston, bolts are not required, and accurate mounting of the upper punch, die, and lower punch can be performed easily and quickly. is there.

[Brief description of drawings]

1 is a sectional view of a powder molding press to which an embodiment of the present invention is applied, FIG. 2 is a plan view of a clamp ring, FIG. 3 is a partial perspective view of a clamp device, and FIG. FIG. 5 is a sectional view of a powder molding press to which another embodiment is applied, and FIG. 5 is a sectional view of a conventional example. 1 ... Support plate (die plate), 4 ... Support plate (upper punch plate), 9 ... Support plate (fixed plate), 12 ... Upper punch, 13 ... Die, 14 ... Lower punch, 21 ... …
Clamp ring, 22 …… rod part, 24 …… flange piece, 25 …… spring, 30 …… hydraulic means, 35 …… piston

Claims (4)

[Claims] 1. A mold clamping device of a powder molding press, wherein an upper punch, a die, and a lower punch are fastened to respective support plates via clamp rings, wherein a cylinder is centered on a clamped mold on the support plate. The donut-shaped piston of the cylinder is provided with a plurality of piston rods on a concentric circle at equal intervals, and an end portion of the piston rod engages with the clamp ring to form a clamp ring. A clamping device for a powder molding press, characterized in that a clamping ring is clamped and released by vertical movement of the piston. 2. A mold clamping device for a powder molding press according to claim 1, wherein the piston is moved up and down by a spring and a hydraulic pressure. 3. The mold clamping device of the powder molding press according to claim 2, wherein the spring is a disc spring. 4. A mold clamping device for a powder molding press according to claim 1, wherein the piston is moved up and down by hydraulic pressure.