JP2883976B2 - Air nipper for gate processing of molded products - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air nipper for gate processing of a molded article used for cutting a runner of a resin molded article at a product side gate.

[0002]

2. Description of the Related Art An air nipper for gate processing of this kind is configured to firstly rotate a pair of nipper blades which are rotatably opened / closed in advance in a cutting operation for driving the pair of nipper blades in a direction of closing the blade edges. It must be moved to the gated position of the part.

Therefore, conventionally, a cylinder device for moving the nipper blade to a predetermined position has been provided separately from a cylinder device for driving the nipper blade for cutting. However, this air nipper has two cylinder devices that perform different operations, and it is necessary to supply air to each of the cylinder devices according to the operation timing, and the configuration is complicated and the size of the device is increased. There was a point.

[0004] Therefore, as disclosed in Japanese Utility Model Publication No. Hei 7-26090, there has been invented an apparatus in which the above operation is continuously performed by one cylinder device. This is shown in FIG.
As shown in the cross-sectional view of FIG. 8 and the bottom view of FIG. 8, the nipper blade body 21 moves in the axial direction following the piston 22 of the cylinder device 20 that drives the nipper blade body 21 in the direction of opening the cutting edge 21a. The output rod 23
A substantially L-shaped operating lever 26 which engages with the output rod 23 is pivotally mounted on a bracket 25 which is provided so as to protrude from a long hole 24a formed on the bottom surface of the cylinder and which movably holds the cylinder device 20 in the axial direction. Further, one side of this operating lever 26 is brought into contact with a contact plate 27 fixed to the cylinder 24, and the piston 22 for driving the nipper blade body 21 is moved, and 24
The cutter itself is pushed through the output rod 23, the operating lever 26, and the abutment plate 27 to move the nipper blade 21 pivotally attached to one side of the cylinder 24 in the lateral direction (the axial direction of the cylinder). Things.

[0005]

The above-mentioned conventional air nipper for gate processing, which has the former two cylinder devices, has a problem that the structure is complicated and the device becomes large as described above. .

In the latter Japanese Utility Model Publication No. Hei 7-26090, the movement and closing operation of the nipper blade can be continuously performed by one cylinder device, so that the device can be downsized and the air can be reduced. Although it is not necessary to measure the supply timing of the cylinder, an elongated hole is provided on the bottom of the cylinder, an output rod is attached to the piston through this elongated hole, and the output rod is attached to the bracket that slidably holds the cylinder. An operating lever that is rotated in contact with it must be pivotally mounted, and a contact plate that this operating lever abuts must be mounted between the bracket and the outside of the cylinder. However, there is a problem that the assembly is difficult.

An object of the present invention is to solve the problems of the conventional gate processing air nipper.

[0008]

According to the present invention, in order to solve the above-mentioned problems, a piston having a tapered surface at the tip, a cylinder in which the piston is slidably fitted closely, and a tip of the cylinder are provided. A pair of nipper blades that are pivotally mounted on the side and are driven in the direction of closing the blade edge by slidingly contacting the tapered surface, a bracket holding the cylinder slidably in the axial direction, and returning the piston to its original shape. In a molded article gate processing air nipper having a spring that biases in the direction, an air supply pipe having an air supply hole communicating with an air chamber formed between the piston and the cylinder is provided at a rear portion of the piston to protrude therefrom, This air supply pipe is composed of a large-diameter portion on the base end side slidably penetrating the rear wall of the cylinder, and a small-diameter portion on the distal end side slidably penetrating the vertical portion of the bracket following the large-diameter portion. Nari, Shirin , The biased by a spring in a direction approaching to the vertical portion of the bracket located behind was set smaller than the urging force of the spring of the piston returning to the biasing force is furnished to the cylinder of the spring.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on the illustrated embodiments.

FIG. 1 is a front view showing an embodiment of an air nipper for gate processing of a molded product according to the present invention, and FIG.
FIG. 4 is a cross-sectional view taken along a line A. As shown, the air nipper for gate processing mainly includes a piston 1 and a piston 1
Slidably fitted in a cylinder 2, a substantially L-shaped bracket 3 in side view holding the cylinder 2 slidably in its axial direction (left-right direction in FIG. 2), and a pivot It is constituted by a pair of nipper blade bodies 4 and 4 attached.

As shown in the plan view of FIG. 6, the piston 1 has a tip (lower side in FIG. 6) recessed in an inverted V or U-shape, and inner surfaces on both sides thereof are tapered surfaces inclined toward each other. 1a, 1a, and a substantially cylindrical air supply pipe 5 protrudes from a rear portion 1b of the piston 1 via a flat convex portion 1c. The air supply pipe 5 has a large-diameter portion 5 on the proximal end side.
a and a small-diameter portion 5b at the distal end continuous with the large-diameter portion 5a, and an air supply passage 6 penetrating the center thereof is bent laterally at a right angle inside the flat convex portion 1c. It is open on the side surface of the flat convex portion 1c. Note that in FIG.
Indicates a seal member for maintaining airtightness between the cylinder 2 and the tightly fitted cylinder 2.

The cylinder 2 has a tip (left side in FIG. 2)
Is provided with an opening 2a in which the tip of the piston 1 can come and go, and a pair of nipper blades 4, 4 can be rotated on the shaft 17 so that the lower half faces the opening 2a. It is attached as follows. Further, a through hole 8a is provided at the center of the rear wall 8 in which the rear end of the cylinder 2 is airtightly closed.
a, a large-diameter portion 5a of an air supply pipe 5 protruding from a rear portion 1b of the piston penetrates airtightly and slidably. Reference numeral 9 denotes a sealing member for maintaining the airtightness. Further, a spring 10 is provided inside the cylinder 2 for pressing the piston 1 against the rear side (the right side in FIG. 2) of the cylinder 2 and returning the piston 1 to its original state.

The nipper blade body 4 has a cutting blade 4a at one end.
And an actuating portion 4b for driving is provided at the other end, and a pair of symmetrically formed left and right members are connected in an X-shape so as to be able to rotate relative to each other as shown in FIG. Thereby, the respective cutting edges 4c, 4c can be driven in the directions of approaching and separating from each other. A spring 11 is elastically provided between the operating portions 4b, 4b, and urges the cutting edges 4c, 4c in a direction to expand.

The bracket 3 is formed by bending a metal plate into a substantially L-shape when viewed from the side. The cylinder 2 is mounted on a horizontal portion 3a, and a pair of flanges are provided so as to sandwich the horizontal portion 3a. The roller 12 is attached to the cylinder 2 by fixing the roller 12 to the lower surface of the cylinder 2 with screws 13. Also,
The vertical portion 3b located behind the cylinder 2 is provided with a through hole 3c through which the small diameter portion 5b of the air supply pipe 5 slidably penetrates, and the pin 14 connected to the rear wall 8 of the cylinder 2 projects in the protruding direction. A cylindrical portion 3d for accommodating and holding the spring 15 (rightward in FIG. 2) is provided. The biasing force of the spring 15 is the same as the above-described spring 1 for returning the piston.
It shall be smaller than the urging force of 0. A screw portion 14a is provided at the tip of the pin 14, and the screw portion 14a is screwed into a mounting portion 8b provided on the rear wall 8 of the cylinder 2 so that the movement distance of the cylinder 2 described later can be adjusted. I have to.

The air nipper for gate processing of a molded article according to the present invention has the above-mentioned structure, is attached to an automatic molded article unloading device (not shown) or the like, and is used for cutting the gate of the molded article. is there.

In FIGS. 2 to 4, reference numeral 31 denotes
2 shows a gate portion interposed between a molded product 30 taken out from a resin molding machine (not shown) and a sprue 32. Although not shown, an air supply hose (not shown) of an air supply means (not shown) such as an air compressor is connected to the air supply section 5 protruding from the rear of the piston 1. And

Next, the operation of the air nipper for gate processing of the molded article of the present invention having the above-mentioned structure will be described. First, the piston 1 is supplied from an air supply means (not shown) via an air supply passage 6.
When compressed air is sent to the air chamber 16 formed between the rear portion 1b of the cylinder 2 and the rear wall 8 of the cylinder 2, the air pressure causes the piston 1 to exert a force that is pushed leftward from the state shown in FIG. Acting, the air supply pipe 5 integral with the piston 1 also tries to move in the same direction. However, as mentioned above, cylinder 2
Is urged by the spring 15 toward the vertical portion 3b of the bracket 3, so that when the piston 1 moves in the cylinder 2 against the urging force of the spring 10, the step 5c of the air supply pipe 5 is The cylinder 2 relatively moves to the right so as to maintain the state of being pressed against the vertical portion 3b. Thereby, the nipper blade body 4 attached to the cylinder 2 moves toward the processing position of the gate portion 31 of the molded product 30.

When the pin mounting portion 8b provided on the rear wall 8 of the cylinder 2 comes into contact with the vertical portion 3b of the bracket 3, the cylinder 2 cannot move any more and stops. At this time, the nipper blade body 4 is located on the base end side of the gate portion 31 of the molded product 30 as shown in FIG.

If compressed air is further fed into the air chamber 16 from this state, the cylinder 2 cannot move as described above, so that the piston 1 moves to the tip side of the cylinder 2 and projects from the opening 2a. The tapered surface 1a of the piston 1 comes into contact with the operating portion 4b of the nipper blade body 4. When the piston 1 further protrudes, the left and right operating portions 4b, 4b are driven in a direction in which they come into sliding contact with the tapered surfaces 1a, 1a, respectively.
c and 4c are driven to close. Therefore, the gate portion 31 of the molded product 30 is connected to the blade portions 4a, 4 of the nipper blade bodies 4, 4.
a and is cut off. FIG. 4 shows this state.

As described above, the gate portion 3 of the molded product 30
1 is to be cut and processed at its proximal end.

Thereafter, a valve (not shown) is operated, and the intake passage 5 is opened to the outside, so that the piston 1 urged by the spring 10 pushes out the air in the air chamber 16 to move the inside of the cylinder 2 rightward. And the tapered surface 1a at the tip is separated from the operating portion 4b of the nipper blade body 4. Therefore, the nipper blades 4, 4 have their cutting edges 4 c, 4
It returns to the initial state where c was expanded.

On the other hand, in the piston 1, the stepped portion 5c of the air supply pipe 5 provided at the rear portion comes into contact with the peripheral edge of the through hole 3c of the bracket 3 and further movement thereof is restricted. The biasing force of the spring 10 acts to press the cylinder 2 to the opposite side (left direction). At this time, the spring 15 for urging the cylinder 2 to move backward (to the right in the drawing) as described above is set to be weaker than the urging force of the spring 10 for returning the piston. 2 overcomes the biasing force of the spring 15 and
Is moved leftward to a position where the head 14b contacts the cylindrical portion 3d. Thus, the air nipper for gate processing of a molded article according to the present invention returns to its original state and prepares for the gate processing of the next molded article.

In the illustrated embodiment, the cylinder 2 is slidably mounted on the bracket 3 by sandwiching the left and right sides of the horizontal portion 3a of the bracket 3 between the flanged rollers 12 mounted on the lower surface of the cylinder 2. However, the cylinder 2 may be slidably attached to the horizontal portion 3a of the bracket 3. For example, a long hole is provided in the horizontal portion 3a of the bracket 3, and a screw is inserted through the long hole to make the cylinder. 2 may be attached to the lower surface.

[0024]

As described above, the air nipper for gate processing of a molded article of the present invention can continuously move the nipper blade body to a predetermined position and perform a cutting operation with only one cylinder device. The size is reduced and the control of the air supply device is simplified. Therefore, it is easy to mount the molded article to an automatic unloading device or the like, and it is also possible to perform a gate processing of a fine molded article, which was difficult with a conventional large-sized apparatus using two cylinder devices.

Further, since a member such as an operating lever serving as a cam is not required and the structure is simple, the assembling process can be easily performed, and the operation can be performed smoothly and reliably. Therefore, the cost is reduced and the reliability of the device is improved.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of an air nipper for gate processing of a molded product according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a cross-sectional view showing a state where a nipper blade body has moved to a gate processing position.

FIG. 4 is a cross-sectional view showing a state where the nipper blade body is performing a cutting operation.

FIG. 5 is a front view of the nipper blade used in the embodiment of the present invention.

FIG. 6 is a plan view of a piston used in the embodiment of the present invention.

FIG. 7 is a sectional view showing a conventional example of an air nipper for gate processing of a molded product.

8 is a bottom view of the air nipper for gate processing of the molded product shown in FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Piston 1a Tapered surface 1b Rear part of piston 1c Flat convex part 2 Cylinder 3 Bracket 3a Horizontal part 3b Vertical part 3c Through-hole 3d Tube part 4 Nipper blade body 4a Blade part 4b Working part 4c Blade tip 5 Air supply pipe 5a Large diameter part 5b Small diameter Part 5c Step part 6 Air supply path 7, 9 Sealing member 8 Rear wall 8a Through hole 10, 11, 15 Spring 12 Flanged roller 13 Screw 14 Pin 14a Screw part 16 Air chamber 17 Axle

Continuation of front page (58) Field surveyed (Int. Cl. ⁶ , DB name) B29C 45/26-45/44 B26B 15/00-17/00

Claims (1)

(57) [Claims] 1. A piston having a tapered surface at its tip, a cylinder in which the piston is slidably fitted, and a direction in which the cutting edge is closed by being pivotally connected to the tip of the cylinder and slidingly contacting the tapered surface. An air nipper for gate processing of a molded product, comprising: a pair of nipper blades driven in the same direction; a bracket holding the cylinder slidably in the axial direction thereof; and a spring for urging the piston in a direction to return to its original state. An air supply pipe having an air supply hole communicating with an air chamber formed between the piston and the cylinder is provided at a rear portion of the piston, and the air supply pipe slidably penetrates a rear wall of the cylinder. The cylinder comprises a large-diameter portion on the base end side, and a small-diameter portion on the distal end side slidably penetrating the vertical portion of the bracket continuous with the large-diameter portion. Biased by a spring in a direction toward the straight portion, the gate processing Eanippa of the molded article, characterized in that the biasing force of the spring is set smaller than the urging force of the spring for the piston return, which is furnished to the cylinder.