JPH06182839A - Clamping device - Google Patents

Abstract

PURPOSE:To prevent a moment from acting on a sprocket and a packing presser at the retraction of a ram by a method wherein a sprocket for positioning a half nut is provided on a guide rod. CONSTITUTION:A guide rod 221 is fixed to a packing presser 210. A bracket 178 of a half nut 180 is slidably provided on the guide rod 221. A sprocket 220 is screwed over the guide rod 221 between the packing presser 210 and the bracket 178. The position of the sprocket 220 can be adjusted by a chain 195. The half nut 180 is positioned by the sprocket 220. Thus, a moment does not occur in the sprocket even after a ram is retracted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold clamping device suitable for an injection molding machine or a die casting machine.

[0002]

2. Description of the Related Art A conventional mold clamping device will be described with reference to FIG. 3. Reference numeral 150 is a base for mounting and fixing the mold clamping device.
A fixed die plate 154 for mounting a fixed mold 152 is fixed to one end of the base 150. 158 is a moving die plate, a moving die 156 is attached to the moving die plate 158 side, and slide shoes 159 are integrally attached to the legs thereof. The slide shoe 159 is mounted so that it can move forward and backward along a guide rail 151 provided on the base 150. The guide portion of the movable die plate 158 may be a sliding slide, a rolling guide, or may be floated by air or magnetic force.

On the other hand, at the four corners of the fixed die plate 154, there are formed hydraulic cylinders 160 for generating a mold clamping force after the mold is closed.
Oil chambers 161A and 161B are provided inside with 62 therebetween. As shown in an enlarged view in FIG. 4, the ram 162 has a multi-tiered outer circumference with large, medium and small diameters, and an insertion hole 174 of the tie bar 164 is formed through the shaft center. When the mold clamping pressure is increased, the one oil chamber 161A is opened. Ram 1 to the right by sending pressure oil to
62 and move the tip 163 of the half nut 180
The half nut 180 with the tie bar 164.
The half nut 180 is further pushed to the right in the state of meshing with each other to generate a mold clamping force. Tie bar 164 is nut 16
5, one end is fixed to the movable die plate 158, and a threaded portion 172 is formed at the tip of the tie bar 164 over a predetermined length. A half nut 180 provided on the back side of the fixed die plate 154 is engaged with the threaded portion 172 during mold clamping. Reference numeral 166 denotes a die opening / closing cylinder attached to the fixed die plate 154 or the moving die plate 158.
8 has the function of moving forward and backward. In this case, the tip of the rod 170 of the mold opening / closing cylinder 166 is fixed to the movable die plate 158 or the fixed die plate 154.

Reference numerals 175 and 176 denote fixed die plates 154.
Is a packing presser that is fixed before and after the portion that constitutes the mold clamping cylinder, and a guide bar 177 is fixed to the packing presser 176 on the rear surface side of the fixed die plate 154, and a nut is attached to the guide bar 177. A half nut 180, which is divided into two and faces each other, is slidably supported via a bracket 178, and the half nut 180 is always urged by a spring 179 so as to be constantly in pressure contact with the tip portion 163 of the ram 162. Also at the same time Ram 162
The end surface 163a of the above is also pressed against the stopper surface 190a of the sprocket 190 described later. The half nut 180 can be opened and closed left and right along a guide bar 181 fixed to the bracket 178 by an opening / closing mechanism (not shown), and is closed during mold clamping to close the screw portion 172 of the tie bar 164.
Mesh with. Further, the screw rod 191 attached to the packing retainer 176 has a sprocket 19 having an internal thread on the inner surface thereof.
0 is in mesh. The sprocket 190 is moved back and forth in a direction indicated by an arrow in FIG. 4 via a chain 195 by a chain drive device such as a stepping motor (not shown) as sprocket positioning means.

Now, in FIG. 3, when pressure oil is sent to one oil chamber 168A of the mold opening / closing cylinder 166, the moving die plate 158 is guided by the guide rail 151 and advances toward the fixed die plate 154 side, and the tip of the tie bar 164 moves. It penetrates through the tie bar insertion hole 174 of the fixed die plate 154 and stops when the fixed die 152 and the moving die 156 come together. The sprocket 190 is previously positioned by driving the chain 195, and hydraulic pressure is applied to the other oil chamber 161B of the hydraulic cylinder 160, so that the end surface 190a of the sprocket 190 and the end surface 163a of the ram 162 as shown in FIG.
The ram 162 is moved leftward in FIG. At this time, the half nut 180 is also the spring 1
The ram 162 moves by being pushed by 79 and moves, and stops when the ram tip 163 and the end surface of the half nut 180 are in pressure contact. The stop position of the half nut 180 is such that when the tie bar 164 penetrates the fixed die plate 154 and stops as described above, the screw portion 172 of the tie bar 164.
The position is determined in advance by the control device so that the phase of the screw and the phase of the screw substantially match. This hydraulic cylinder 16
0 is provided corresponding to each of the four tie bars 164.

Upon completion of mold closing, the half nut 180 is closed by a half nut opening / closing device (not shown),
Next, hydraulic pressure is applied to the oil chamber 161A of the hydraulic cylinder 160. Tie bar 164 screw 172 and half nut 180
Since the screw is already in mesh with each other at this time, the half nut 180 is pushed to the right by the ram tip portion 163, whereby the tie bar 164 is pulled and a mold clamping force is generated. When the mold is finished and the mold is opened, first the hydraulic cylinder 16
The hydraulic pressure of the oil chamber 161A of 0 is lowered, then the half nut 180 is opened from a half nut opening / closing device (not shown) to release the meshing with the tie bar 164, and then pressure oil is sent to the oil chamber 168B of the mold opening / closing cylinder 166 to move. The die plate 158 moves to the left and the mold opens.

[0007]

In the above-described conventional mold clamping device, the fixed mold 152 and the movable mold 156 are combined by the mold opening / closing cylinder 166 to complete the mold closing, and then the half nut 180 is closed to close the tie bar 164. Screw part 172
Oil chamber 1 to match the phase of the threads.
The hydraulic pressure is sent to 61B to move the ram 162 to the left,
Pre-positioned sprocket 190 end face 190a
The movement is stopped when the end surface 163a of the ram 162 abuts. At this time, the reaction force that stops the ram 162 against the hydraulic pressure is from the sprocket 190 to the screw rod 19
However, since there is only one threaded rod 191 and it is located at a position on the circumference eccentric with respect to the axis of the ram 162, a bending moment is given to the packing retainer 176. Therefore, a relatively large force or moment from the ram 162 is applied to the sprocket 190, the screw rod 191, and the packing retainer 176, and the members are adversely affected by wear or deformation. SUMMARY OF THE INVENTION The present invention provides a mold clamping device in which an excessive acting force does not act on a sprocket, a guide rod, and a packing presser when positioning the half nut 180, and is intended to solve the conventional problems. .

[0008]

Therefore, the present invention provides a fixed die plate for holding a fixed die, a movable die plate for holding a movable die, a means for moving the movable die plate, and the movable die. A mold clamping device comprising a plate and a tie bar for clamping the mold after the mold is closed, the mold clamping device comprises a ram, a packing retainer configured to restrict the amount of movement of the ram, and the packing retainer. A guide rod fixed to the guide rod, a sprocket screwed to the guide rod, a half nut slidably fitted to the guide rod, and a half nut fitted to the guide rod to the sprocket. And a positioning means for positioning the sprocket, and the half nut has a protruding ram. Can abuts the same ram, when the ram is retracted in the half nut than that so as to be positioned by the sprockets, it is an unit for which a problem solution.

[0009]

According to the present invention, when the ram is moved leftward by the hydraulic cylinder, the half nut is moved leftward together with the ram by the spring, and the bracket of the half nut abuts on the sprocket and is stopped and positioned. . After that, only the ram moves to the left, and the flange of the ram comes into contact with the packing retainer and stops. The sprocket is rotationally driven by a chain and moves in the axial direction of the ram to adjust the position. Positioning for closing the half nut is performed by moving the ram to the left by the hydraulic cylinder as described above.At the end of this positioning operation, the half nut is separated from the ram and remains in a fixed position. The ram comes into contact with the sprocket and stops, and the ram comes into contact with the packing retainer along the entire circumference of its flange and stops. As a result, a large force is not applied from the ram to the sprocket and the screw rod, and a force distributed over the entire circumference is applied only to the packing presser, and the conventional moment is not applied.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiments of the drawings. FIG. 1 is a longitudinal sectional view of a hydraulic cylinder portion of a fixed die plate in a mold clamping device showing an embodiment of the present invention, and an explanatory view of a conventional device It corresponds to 4. In FIG. 1, the same components as those of the conventional device are designated by the same reference numerals and the description thereof will be omitted. In the figure, 200 is a ram having a flange portion 200a, and 210 is a flange portion 210a.
The packing retainer 220 includes a sprocket 220 having an internal thread on its inner diameter portion, and the guide rod 221 is a guide rod fixed to the packing retainer 210. Guide rod 221
Is slidably inserted in the bracket 178 of the half nut 180, and a female screw is provided on the packing retainer 210 side and is screwed with the female screw of the sprocket 220.
A stopper head is provided at the other end, and a spring 179 is interposed between the stopper head and the bracket 178, and the spring 179 urges the bracket 178 to push toward the sprocket 220. Also sprocket 2
20 is a chain 19 as sprocket positioning means
It is rotationally driven by 5 and can be moved in the left-right direction in the figure.

The operation of the embodiment configured as described above will be described below. When the fixed mold and the movable mold are open, the ram 200 is located at the left side position in FIG. The right side surface and the left side surface of the bracket 178 are in contact with each other, and there is a gap between the right side surface of the flange portion 200a of the ram 200 and the left side surface of the half nut 180. After the movable die plate 158 is moved to the right by the rod 170 of the opening / closing cylinder and the mold is closed, the half nut 180 is engaged with the thread portion 172 of the tie bar 164 by a half nut opening / closing device (not shown). At this time, the half nut 180 and the thread portion 17 of the tie bar
Sprocket 22 beforehand so that the phases of the 2 screw threads match.
The position of 0 is adjusted by the chain 195.

Next, the oil chamber 161A of the hydraulic cylinder 160
Generates mold clamping force by sending pressure oil to. At this time, as shown in FIG. 2, the right side surface of the flange portion 200a of the ram 200 and the left side surface of the half nut 180 are in contact with each other, and there is a gap between the right side surface of the sprocket 220 and the left side surface of the bracket 178. ing. After the molding work, the oil chamber 16
Lower the hydraulic pressure of 1A and open the half nut 180. After that, pressure oil is supplied to the oil chamber 161B, and the ram 200 moves to the left. The half nut 180 abuts on the sprocket 220 and is stopped by the biasing force of the spring 179. The ram 200 continues to move further to the left, and the packing retainer 210
It comes into contact with the flange portion 210a of the and stops. Next, the movable die plate 15 is moved by the rod 170 of the opening / closing cylinder.
Opening 8 to the left is the same as before, with the ram 200 returning to its initial leftward position.

[0013]

As described in detail above, according to the present invention, the ram is moved by the hydraulic cylinder in order to stop the half nut at a fixed position after the molding work is completed. It does not act on the sprocket and guide rod of the small member for stopping, and acts on the packing retainer of the large member without a moment.Therefore, excessive force acts on the sprocket, the guide rod, and the retainer of the packing. Therefore, the same member is not adversely affected by wear and deformation.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a ram portion of a mold clamping device according to an embodiment of the present invention.

FIG. 2 is a partially enlarged view of FIG.

FIG. 3 is a vertical cross-sectional view of a conventional mold clamping device in a mold open state.

FIG. 4 is an enlarged vertical sectional view of a ram portion in FIG.

[Explanation of symbols]

 152 Fixed mold 154 Fixed die plate 156 Moving mold 158 Moving die plate 164 Tie bar 178 Half nut 179 Spring 180 Half nut 195 Chain 200 Ram 210 Packing foot 220 Sprocket 221 Guide rod

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[Procedure amendment]

[Submission date] May 27, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 1

[Correction method] Change

[Correction content]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0003

[Correction method] Change

[Correction content]

On the other hand, at the four corners of the fixed die plate 154, there are formed hydraulic cylinders 160 for generating a mold clamping force after the mold is closed.
Oil chambers 161A and 161B are provided inside with 62 therebetween. As shown in an enlarged view in FIG. 4, the ram 162 has a multi-tiered outer circumference with large, medium and small diameters, and an insertion hole 174 of the tie bar 164 is formed through the axial center thereof. Ram 1 to the right by sending pressure oil to
62 and move the tip 163 of the half nut 180
The half nut 180 with the tie bar 164.
The half nut 180 is further pushed to the right in the state of meshing with each other to generate a mold clamping force. Tie bar 164 is nut 16
5, one end is fixed to the movable die plate 158, and a threaded portion 172 is formed at the tip of the tie bar 164 over a predetermined length. A half nut 180 provided on the back side of the fixed die plate 154 is engaged with the threaded portion 172 during mold clamping. Reference numeral 166 denotes a die opening / closing cylinder attached to the fixed die plate 154 or the moving die plate 158.
8 has the function of moving forward and backward. Therefore , the tip of the rod 170 of the mold opening / closing cylinder 166 is fixed to the movable die plate 158 or the fixed die plate 154.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction content]

[0007]

In the above-described conventional mold clamping device, the fixed mold 152 and the movable mold 156 are combined by the mold opening / closing cylinder 166 to complete the mold closing, and then the half nut 180 is closed to close the tie bar 164. Screw part 172
Oil chamber 1 to match the phase of the threads.
The pressure oil is sent to 61B to move the ram 162 to the left,
Pre-positioned sprocket 190 end face 190a
The movement is stopped when the end surface 163a of the ram 162 abuts. At this time, the reaction force that stops the ram 162 against the hydraulic pressure is from the sprocket 190 to the screw rod 19
However, since there is only one threaded rod 191 and it is located at a position on the circumference eccentric with respect to the axis of the ram 162, a bending moment is given to the packing retainer 176. Therefore, a relatively large force or moment from the ram 162 is applied to the sprocket 190, the screw rod 191, and the packing retainer 176, and the members are adversely affected by wear or deformation. SUMMARY OF THE INVENTION The present invention provides a mold clamping device in which an excessive acting force does not act on a sprocket, a guide rod, and a packing presser when positioning the half nut 180, and is intended to solve the conventional problems. .

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction content]

[0008]

Therefore, the present invention provides a fixed die plate for holding a fixed die, a movable die plate for holding a movable die, a means for moving the movable die plate, and the movable die. A mold clamping device comprising a plate and a tie bar for clamping the mold after the mold is closed, the mold clamping device comprises a ram, a packing retainer configured to restrict the amount of movement of the ram, and the packing retainer. A guide rod fixed to the guide rod, a sprocket screwed to the guide rod, a bracket slidably fitted on the guide rod, and a half nut supported by the bracket. A spring externally fitted to the guide rod and biasing the half nut so as to push the half nut in the direction of the sprocket; and a positioning means for positioning the sprocket. The half nut contacts the ram when the ram protrudes, and the half nut is positioned by the sprocket when the ram retracts. It is what

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction content]

[0009]

According to the present invention, when the ram is moved to the left by the hydraulic cylinder, the half nut is moved leftward together with the ram by a spring, bracket the half nut in the middle is positioned to stop in contact with the sprocket It After that, only the ram moves to the left, and the flange of the ram comes into contact with the packing retainer and stops. The sprocket is rotationally driven by a chain and moves in the axial direction of the ram to adjust the position. Positioning for closing the half nut is performed by moving the ram to the left by the hydraulic cylinder as described above.At the end of this positioning operation, the half nut is separated from the ram and remains in a fixed position. The ram comes into contact with the sprocket and stops, and the ram comes into contact with the packing retainer along the entire circumference of its flange and stops. As a result, a large force is not applied from the ram to the sprocket and the screw rod, and a force distributed over the entire circumference is applied only to the packing presser, and the conventional moment is not applied.

[Procedure correction 6]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction content]

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiments of the drawings. FIG. 1 is a longitudinal sectional view of a hydraulic cylinder portion of a fixed die plate in a mold clamping device showing an embodiment of the present invention, and an explanatory view of a conventional device It corresponds to 4. In FIG. 1, the same components as those of the conventional device are designated by the same reference numerals and the description thereof will be omitted. In the figure, 200 is a ram having a flange portion 200a, and 210 is a flange portion 210a.
The packing retainer 220 includes a sprocket 220 having an internal thread on its inner diameter portion, and the guide rod 221 is a guide rod fixed to the packing retainer 210. Guide rod 221
Is slidably inserted into the bracket 178 of the half nut 180, the gland 210 side male screw is provided, and screwed into the internal thread of the sprocket 220,
A stopper head is provided at the other end, and a spring 179 is interposed between the stopper head and the bracket 178, and the spring 179 urges the bracket 178 to push toward the sprocket 220. Also sprocket 2
20 is a chain 19 as sprocket positioning means
It is rotationally driven by 5 and can be moved in the left-right direction in the figure.

[Procedure Amendment 7]

[Document name to be amended] Statement

[Name of item to be corrected] Brief description of the drawing

[Correction method] Change

[Correction content]

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a ram portion of a mold clamping device according to an embodiment of the present invention.

FIG. 2 is a partially enlarged view of FIG.

FIG. 3 is a vertical cross-sectional view of a conventional mold clamping device in a mold open state.

FIG. 4 is an enlarged vertical sectional view of a ram portion in FIG.

[Explanation of reference symbols] 152 Fixed mold 154 Fixed die plate 156 Moving mold 158 Moving die plate 164 Tie bar 178 Bracket 179 Spring 180 Half nut 195 Chain 200 Ram 210 Packing foot 220 Sprocket 221 Guide rod

Claims (1)

[Claims] 1. A fixed die plate for holding a fixed die, a movable die plate for holding a movable die, a means for moving the movable die plate, a fixed die plate coupled with the movable die plate, and after closing the die. In a mold clamping device composed of a tie bar for performing mold clamping, the mold clamping device includes a ram, a packing retainer configured to restrict the movement amount of the ram, and a guide rod fixed to the packing retainer.
A sprocket screwed to the guide rod, a half nut slidably fitted to the guide rod, and a half nut fitted to the guide rod so as to push the half nut toward the sprocket. A spring and a positioning means for positioning the sprocket are provided. The half nut contacts the ram when the ram projects and the half nut is positioned by the sprocket when the ram retracts. A mold clamping device characterized by being configured accordingly.