JPH0815635B2 - Spring cutting mechanism - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spring cutting mechanism, and more particularly to a spring cutting mechanism for cutting sequentially manufactured springs.

[0002]

2. Description of the Related Art The applicant of the present application has previously filed Japanese Patent Application No. 4-1981.
No. 93 (filed on July 24, 1992), the wire rod is forcibly supplied to the point tool, and thus the wire rod is caused to have a diameter, and the wire rod having a diameter (curved) is laterally moved. We proposed a technique to give a spring pitch by pushing the wedge member with a sharp blade between wire rods that are pushed in a direction (almost perpendicular to the bending surface) or curved.

In this case, the wire rod is shut off from the core by causing the cutter to reciprocate in one-dimensional direction.

FIG. 7 shows the state of this interruption.
In the figure, reference numeral 81 is a wire that serves as a base of a spring, 82 and 83 are point tools, 84 is a core, and 85 is a cutter.

When the wire rod 81 is fed in the direction of the arrow in the figure, it comes into contact with the point tool 82. When the wire rod 81 is further forcibly fed, it is bent by the point tool 82 and reaches the core 84 through the point tool 83 (not necessarily required). Details of the principle of giving a pitch to the spring are omitted.

Thus, when the feeding of the wire required for one spring is completed, the feeding of the wire is stopped and the cutter 85
Move downwards in the figure to move the center rod 84 and cutter 85.
The wire rod 81 is cut with and. FIG. 8 shows a sequence during this disconnection.

[0007]

However, while the cutting is completed and the cutter 85 is pulled up in the direction A in the drawing, the uncut wire rod (which becomes the next spring) is pressed against the side surface of the cutter 85. That is, while the cutter 85 is being pulled up, the cutter 85 rises while rubbing the cut surface of the wire rod 81. When the wire has a relatively large diameter of several millimeters or more, this frictional force (or pressure contact force) becomes considerable.

As a result, the blade portion of the cutter is damaged or scraped off, which makes the cutter extremely short-lived.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is an object of the present invention to provide a spring cutting mechanism capable of realizing not only the life extension of a cutter but also an extremely simple structure thereof. It is a thing.

In order to solve this problem, the spring cutting mechanism of the present invention has the following structure. That is, in a spring cutting mechanism of a device for manufacturing a spring by supplying a wire material to a point tool in the vicinity of a spring forming portion and forcibly bending the point tool by applying the wire material to generate a diameter. , A cam having a force point shaft which is rotated by a motor and extends from a position separated from the rotating shaft by a predetermined distance, and a side surface of the cam, which is in contact with a side surface of the cam and is substantially perpendicular to the supply direction of the wire. Attach a slider part that moves in the direction of and a cutter for cutting the spring wire near one end,
A cutter mount which has an operating shaft extending near the other end and is rotatably attached to the slider portion at a substantially central position, and a rotatably rotatably supporting end near the predetermined fixed shaft. And a link member that slidably holds the force point axis and the action axis.

[0011]

In the structure of the present invention, when the cam rotates or rotates, the cutter mount attached to the slider section makes a one-dimensional motion. During this time, the link member attached to the fixed shaft performs a pendulum motion by the circular motion of the force point shaft extending from the cam about the fixed shaft. As a result, the working shaft of the cutter mount is swung, and the cutter mount rotates about the mounting shaft to the slider portion. As a result, the cutter attached near the end of the cutter mount is shaken, and the movement of the entire cutter becomes an elliptical movement.

[0012]

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

The manufacturing of the spring in the embodiment is based on the previously proposed Japanese Patent Application No. 4-198193, and the principle of manufacturing the spring will be briefly described below.

[Explanation of Spring Pitch Forming by Wedge Method] FIG. 1 shows the structure of the main parts relating to the spring manufacturing in the wedge method. Each constituent part will be described below according to its operation.

The wire rod 1 from a wire rod supply source (not shown) is inserted into guide grooves (not shown) provided in the wire rod guides 2a and 2b. Feed rollers 3a and 3b for sandwiching the wire rods are provided at substantially central positions of the wire rod guides 2a and 2b. These feed rollers 3a and 3b are rotated in a direction indicated by an arrow by a wire rod feed motor, which will be described later, to
Are conveyed in the y direction. Wire guide 2b
The wire rod discharged from the end of is applied to the point tools 4a and 4b and forcedly bent in a plane substantially parallel to the yz plane. At this time, the wire rod 1 is the point tool 4
The diameter is given according to the positions of a and 4b.
Although not directly related to the invention of the present application, the point tools 4a and 4b can be moved in the direction of the arrow shown by a point shaft motor, which will be described later, during the manufacture of one spring. Thus, for example, it is possible to manufacture a tapered spring. Further, a groove is provided on the contact surface with the wire rod 1 so that the wire rod bent by the point tools 4a and 4b can be surely bent in a predetermined direction.

When the feed rollers 3a and 3b continue to rotate in the above-mentioned state, a spring is generated in which the wound wire rods are in close contact with each other. Here, when the wedge tool 6 is raised in the z direction. The blade portion 6a cuts in as shown. As a result, a spring having a pitch of zero (actually, a spring having a pitch corresponding to the thickness of the wire) is molded in a pitched state.

When one spring is manufactured in this way, the cutting tool 7 is lowered (moved in the -z direction) by a cutting shaft motor, which will be described later, and the wire 1 is cut between the core 5 and the core 5.

[Description of Spring Pitch Forming by Push Method] Next, spring pitch forming by the push method in the embodiment will be described.

FIG. 2 shows the structure of the main part relating to the spring manufacturing in the push method. The difference from FIG. 1 is that a push tool 22 is provided instead of the wedge tool 6. As shown in the point tool 21, mount portions for fixing the point tool are provided in advance at several positions in the actual spring forming portion so that the position of the point tool can be changed. However, the position of this point tool may be that of FIG.

In the configuration of FIG. 2, the operation of supplying the wire rod 1 and forcibly bending it by the point tool 21 is the same as that of the wedge system described above. The difference is that the push tool 22 moves in the direction of the arrow,
The point is that the pitch is formed by extruding the wire rod immediately after being bent in the x direction.

In Japanese Patent Application No. 4-198193, the wedge method and the push method can be realized by the same drive source and the switching can be easily performed, but since they are not directly related to the invention of the present application. , Description is omitted.

[Explanation of Spring Cutting Mechanism] In any of the above cases, when the feeding of the wire rod 1 required for manufacturing one spring is completed, the cutter 7 moves and the wire rod 1 between the core rod 5 is moved. However, if the cutter 7 reciprocates only along the z-axis, the problems described above occur.

Therefore, in this embodiment, the movement (trajectory) of the cutter 7 is set to follow an elliptical orbit at least in the vicinity of cutting as shown in FIG.

By performing this movement of the cutter in this way, the cutter is used for the cutter 7 of the wire rod 1 left after cutting while cutting and returning to the original position after cutting is completed. Since the wire 7 is moved away from the wire 7, the wire rod 1 is substantially not pressed against the cutter 7.
It should be noted that the illustration is exaggerated, and in reality, the lateral displacement of the cutter 7 is about several millimeters.

A structure for realizing the above-mentioned movement is shown in FIG. 4, and each structure will be described below together with its operation.

The slider portion 32 is attached to the slide base 31 slidably in the vertical direction in the figure. Also,
A rotatable cam follower (not shown) is attached to the upper end of the slider portion 32. The cam follower is attached to the upper portion of the slide base 31.
It is in contact with the side of 0. Further, in order to always pull the slider portion 32 upward, one end of each of the cam springs 35a and 35b is a cam spring attachment portion 34 (fixed to the slider portion 32), and the other end is a lower portion of the slide base. Mounted on a spring mounting shaft 39 at. The cam 30 is rotated by being driven by a cutter motor (not shown).

Therefore, when the cutter motor is driven, the cam 30 rotates in the direction of the arrow a, and as a result, the slider portion 32 moves in the vertical direction. In other words, the cutter mount 40 attached to the slider portion 32 moves up and down, and as a result, the cutter 7 moves up and down.

Next, the principle of the horizontal movement of the cutter 7 will be described.

The cutter mount 40 is attached to the slider portion 32 so as to be rotatable about the shaft 41 in the direction of arrow b in the figure. The cutter 7 is crimp-fixed (removable) to the cutter mount 40 as shown in the figure.

On the other hand, a fulcrum shaft 50 is attached to the upper part of the slide base 31. The bearing hole 52 of the link member 51 is inserted into the fulcrum shaft 50 (however, the link member 51 is prevented from falling off), and the link member 51 is rotatably attached with the fulcrum shaft 50 as a fulcrum.

A force point shaft 53 extends from the cam 30. However, as shown in FIG. 6, the center Q of the force application axis 54 is a predetermined distance Δx from the center P of the rotation axis of the cam 30.
(Actually a few millimeters).

The power point shaft 54 is inserted into a bearing hole 56 provided in the slider piece 55. And this slider part 5
5 is attached slidably along the slide groove 53 of the link member 52.

As a result, when the cam 30 is rotated by the action of the cutter motor, the force application shaft 54 causes a circular motion about the rotation axis P of the cam 30. Then, the slider piece 55 moves up and down along the guide groove 53 of the link member 52, and the link member 51 moves along the fulcrum shaft 50.
As shown by an arrow c in the figure, the same movement as a pendulum of a watch is performed.

A shaft 42 is provided above the cutter mount 40, and a slider piece 57 having a bearing hole 58 for receiving the shaft 42 is provided in the guide groove 53 of the link member 52.
It is slidably attached to. Of course, the slider piece 57 is rotatable with respect to the shaft 42.

As described above, the cutter mount 4
Since 0 is rotatable about the shaft 41, as described above, when the link member 52 causes the pendulum motion (at this time, the slider piece 57 moves up and down along the guide groove 53 of the link member 52). The shaft 42 is also swung left and right. As a result, the cutter mount 40 moves about the shaft 41 in the direction of the arrow b in the figure.

During this time, the slider portion 32 moves up and down by the rotation of the cam 30, so that the tip of the cutter 7 makes an elliptical movement as shown in FIG.

In FIG. 5, half of the elliptic movement is substantially horizontal because half of the cam 30 is substantially a perfect circle (having a uniform radius). This serves to narrow the vertical movement range of the cutter mount 40.

Although the link member 51 is shown as covering the slider pieces 55 and 57 in the figure, in reality,
Although the link member 52 is slidable, guides are provided so that the slider pieces 55 and 57 cannot be disengaged.

[Description of Control Unit] FIG. 5 shows an example of the structure of the control unit for realizing the above-described processing.

In the figure, 100 is a CPU that controls the entire apparatus, and 101 is an operating section for setting various parameters in spring manufacturing, giving an operation or a stop instruction, and shows the operation contents and the state of the apparatus. Display unit 10 for
2 are provided. The CPU 100 is provided with a ROM that stores the operation processing procedure and a RAM that is used as a work area. Reference numerals 105 to 108 are drivers for each motor (all are servo motors) described below. Reference numeral 109 is a wire feed motor, which is a rotational drive source for the feed rollers 3a and 3b. Reference numeral 110 denotes a pitch axis motor, which is a motion source of the wedge tool 6 of FIG. 1 or the push tool 22 of FIG. Reference numeral 111 denotes a point axis motor for moving the point tools 4a and 4b in FIG. 1 or the point tool 21 in FIG. The point shaft motor 111 is mainly driven when manufacturing a tapered spring. Reference numeral 112 is a motor that causes the cam 30 to rotate. As described above, the spring manufacturing apparatus of the embodiment has four motors.

Here, the CPU for manufacturing the spring of the embodiment
The operation processing procedure of 100 will be briefly described.

[0042] From operation 101, previously what size,
It is assumed that various conditions such as how many free-length springs are manufactured are input. For the sake of simplicity, it is assumed that the point shaft motor is not driven and a spring having a uniform diameter is manufactured.

Now, in order to manufacture the instructed spring, the CPU 101 calculates the wire rod length required for it, and drives the wire rod feed motor 109 in order to feed the wire rod of that length. Drive accordingly.

When it is determined that the wire for one spring has been supplied, the wire feed motor and the pitch axis motor 110 are stopped. Then, the cut shaft motor 112 is driven to drive the cam 3
0 is rotated once to cut the wire 1.

In this way, the same process is repeated until a preset number of springs are manufactured.

In addition to the parameters described above, various parameters such as the information spring pitch for specifying the shape of the spring and the outer diameter (whether the shape is tapered or not) are set as the parameters set from the operation unit 101. There is something. The rotation speed and the rotation speed of each motor described above are determined according to the information that specifies the shape of the spring, but the description is omitted because it is not directly related to the present invention.

In the embodiment, regardless of the wire diameter,
The elliptic movement of the cutter 7 is constant, but the locus of this elliptic movement may be changed according to parameters such as the diameter of the wire. For example, the axis 4 of the cutter mount 42
It is possible to easily switch the positions if the positions of 2 and the position of the rotary shaft 41 are slightly different from each other.

As described above, according to the spring manufacturing apparatus of the present embodiment, the cutter 7 has a trajectory that is an elliptical trajectory in the vicinity of the wire cutting, so that the life of the cutter 7 can be extended.
Further, as a structure for realizing this elliptical orbit, an accurate elliptical orbit is generated only by the movement of the cam 30 which rotates (or rotates) by one drive shaft, and by making the structure extremely simple. It will be possible.

Incidentally, compared with the conventional cutter movement caused by the movement in the one-dimensional direction, according to the structure of this embodiment, the life was extended several times to several tens of times.

Also, so-called "burrs" were liable to occur on the cut surface of the wire rod in the past, but the shape of the cut surface could obtain a very good result by the structure of this embodiment.

[0051]

As described above, according to the present invention, the life of the cutter used for manufacturing the spring can be extended, and the cutter can be realized with an extremely simple structure and can be cut accurately.

[0052]

[Brief description of drawings]

FIG. 1 is a view for explaining the structure and operation of a wedge manufacturing spring manufacturing portion in an embodiment.

2A and 2B are views for explaining the structure and operation of the spring manufacturing portion by the push method in the embodiment.

FIG. 3 is a block configuration diagram of a control unit of the spring manufacturing apparatus in the embodiment.

FIG. 4 is a diagram showing a structure for generating movement of a cutter for cutting a spring in an embodiment.

FIG. 5 is a diagram showing a motion locus of the cutter of the embodiment.

FIG. 6 is a diagram showing a relationship between a rotary shaft of a cam and a force point shaft fixed to the cam according to the embodiment.

FIG. 7 is a diagram showing a motion direction of a cutter for a normal spring cutting.

FIG. 8 is a diagram showing a sequence of cutter movement for normal spring cutting.

[Explanation of symbols] 1 wire rod 2a, 2b wire rod guide 3a, 3b feed roller 4a, 4b and 21 point tool 5 core girder 6 wedge tool 7 cutting tool 22 push tool 30 cam 31 slide base 32 slider 40 cutter mount 50 fulcrum shaft 51 Link member 54 Force point shaft 55, 57 Slider piece

Claims (1)

[Claims] 1. A spring of an apparatus for manufacturing a spring by supplying a wire rod to a point tool in the vicinity of a spring forming portion and forcibly bending the point tool by applying the wire rod to generate a diameter. In the cutting mechanism, a cam having a force point shaft which is rotated by a motor and extends from a position separated from the rotating shaft by a predetermined distance, and a side surface of the cam are brought into contact with each other in the feeding direction of the wire. A slider part that moves in a substantially vertical direction and a cutter for cutting the spring wire are attached near one end, and an operating shaft that extends near the other end is provided. A cutter mount rotatably attached to the rotary shaft, and a link member rotatably supported near the end by a predetermined fixed shaft and slidably holding the force point shaft and the action shaft. Characteristic The cutting mechanism.