JPS6359776B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is capable of forming various coil springs by bending the flow direction of the strands when the strands collide with a forming tool that advances to the front of the strands fed out from the quill by a pair of delivery rollers. This invention relates to improvements in support means for forming tools in automatic spring manufacturing machines and machine control.

As an automatic spring manufacturing machine, for example, one manufactured by US Baird Co., Ltd. is widely available on the market, and its structure is widely known from Japanese Patent Publication No. 3025890, published in Japanese Patent Publication No. 37-6714. That is, in this type of wire, the forming tool advances in front of the wire fed out from the quill and is oscillated so as to intersect with the quill axis.

In this case, the lever supporting the forming tool is pivotally supported at its center, and the opposite end of the lever to the tool support is connected so as to be subject to cam control. By the way, in this structure, the tool and the pivot point are arranged on the opposite side of the quill so that the angle at which the molding surface passes through the front surface of the quill does not interfere with molding. Therefore, the lever supporting the tool is constructed to cross the side of the quill, and even if the tools are provided to surround the quill, there are at most four tools spaced 90 degrees apart, making it possible to manufacture British-style coil springs. However, problems arise in the production of, for example, German or special coil springs, which require more tools than this. Therefore, let's consider the reason why the pivot point of the lever is forced to be located on the opposite side of the tool. The strand that abuts the forming surface of the tool that advances to the front of the quill receives a force that flows almost symmetrically with respect to the normal line at the abutting point of the forming surface, and after the strand collides, the direction of flow is changed in a curved line. Ru. In this case, the size of the arc of the curve is mainly influenced by the distance from the front end of the quill to the abutment point of the tool (FIG. 27). Also, the angle that the forming surface of the tool makes with the feeding direction of the strands, that is, the quill axis, is important for coil formation. The angle at which the forming surface intersects the quill axis when the tool moves in a circular arc with the turning of the lever is not uniform depending on conditions such as the coil diameter and wire diameter. This angle is determined by the inclination angle of the forming surface with respect to the longitudinal axis of the tool, the attachment angle of the tool to the tool support lever, and the relative position between the abutment point and the center of rotation of the lever. Generally, it is determined by the angle of the inclined surface provided as a forming surface on the tool itself. When forming so that the diameter of the coil part changes continuously, the direction of the angle that intersects the quill axis changes during the turning of the tool, so that the lever is turned in such a way that the forming surface does not roll into the quill side. Determining the position of the pivot point. The angle range is usually 60 degrees tilted from the quill axis (Figure 26). Practically speaking, the angle of inclination is 30 degrees rather than 5 degrees, and the utilization rate is particularly high at around 10 degrees. To facilitate understanding, assume that the tool is used in a state where the inclination angle of the molding surface is zero, that is, the molding surface is perpendicular to the quill axis, and the pivot axis of the lever is on the quill axis. When the lever is rotated and aligned with the quill axis, the tool forming surface at the tip of the lever is perpendicular to the quill axis. However, before matching, the intersection angle is an acute angle from the perpendicular line, and when the strand abuts the forming surface of the tool at such an angle, the flow is diverted along the forming surface and a coil is wound. On the other hand, the intersecting angle after matching with the quill axis changes to an acute angle in the opposite direction to the perpendicular line. Therefore, the flow direction of the strands is reversed by 180 degrees. Therefore, if the coil diameter is changed while the coil is being formed, for example, when entering the coil body from the base of the locking part, it is necessary to change the distance from the quill end to the abutment point, so the quill diameter may be changed while the lever is turning. When taking a tool curve trajectory in which the distance from the end to the abutting point of the tool changes, the intersection angle reverses halfway, changing the flow direction of the strands to be opposite to the quill axis, making it impossible to form a coil. Become. Therefore, in order to perform molding so that the coil diameter changes continuously, it is necessary to continuously change the distance between the quill end and the tool molding, and to keep the angular direction of the molding surface the same.
In this case, since it is necessary to ensure that the intersection angle between the forming surface and the quill axis always remains in the same direction while the lever continues to rotate, it is necessary that the pivot center of the lever be on the opposite side of the tool. As mentioned above, this results in a restriction on the number of tools depending on the lever mounting structure, which causes problems in the formation of various springs.

Therefore, in view of the above points, the present invention has been made to eliminate the disadvantage of being limited by the number of tools, and its purpose is to always maintain a stable direction of intersecting angle during the oscillating movement of the tools. The object is to provide a tool support mechanism that allows the tool to be held. Another object of the present invention is to provide a tool support mechanism in which a large number of tools can be mounted radially around the quill. Still another object is to enable an automatic spring manufacturing machine with an increased number of tools to handle a wide variety of springs and realize efficient production. That is, the tools are constructed by fastening one link onto a fixed four-bar link, the supporting member is a unit, and all of the tools are arranged radially around the quill on the same side as the tool. In addition, a pair of feed rollers are commanded and the rotation of a cam that moves the tool is controlled by commands, and both are simultaneously controlled in a relational manner to produce special shapes such as coil bodies by temporally overlapping the operations of the wire feed tool. It is also intended to respond to streamlining.

Next, the embodiment will be explained with reference to the drawings.

(A) Wire feeding mechanism A feed roller 4 having a semicircular groove for feeding the strands on its circumference is fixed to a roller shaft 3 supported by a bracket 2 supported on the machine frame 1. This feed-out roller is formed by a pair of upper and lower opposed rollers, and accurately grips the wire and feeds it out in a direction perpendicular to the tool mounting surface of the machine frame 1. The delivery roller and the quill described later are replaced depending on the thickness of the wire. In addition, the initial insertion of the wire into the quill hole is performed by widening the distance between the rollers by operating the adjustment handle 5. Gears 6 are fixed to the ends of the roller shafts 3 and mesh with each other, so that the delivery rollers are rotated in opposite directions. One of the roller shafts 3 is connected via a gear group 7 to a servo motor 9 of a reduction gear 8 provided in the machine frame 1 . This servo motor, which is controlled by commands from a numerical control device to be described later, rotates the delivery roller intermittently. Also, a tacho generator (hereinafter referred to as GT) 10 detects the rotation speed of the servo motor.
and a detector 11 for detecting the feed length of the wire from the rotation of the feed roller 4. A quill holder 12 is provided opposite to the front plate of the machine frame in front of the circular guide groove formed by each semicircular groove of a pair of feed rollers, and the quill holder 12 has a quill 13 having a through hole through which the wire passes. It is attached in a replaceable manner.

(B) Tool-related mechanism On the upper half of the tool mounting surface of the front plate of the machine frame 1, which is perpendicular to the quill, forming tools No. 1 to No. 5 are arranged radially at 45-degree intervals around the quill 13 toward the center. There is. On the lower half of the tool mounting surface of the front plate, a No. 7 forming tool is placed vertically in the center, and No. 6 and No. 8 cutting tools are arranged radially at 30 degrees on either side. The support structure of this forming tool is the first feature, and its details will be explained below. A rectangular pedestal 14 fastened to the front plate
Two L-shaped levers 15 and 16 are pivotally supported at a distance. A link 19 having the same length as the distance between the pivot points of the base 14, that is, the fixed link 14', is pivotally connected to the equal length points of the levers 15 and 16. The lever 15, the link 19, the lever 16, and the fixed link 14' form a four-bar parallel link with equal opposite sides. The four-bar parallel link is normally configured to swing within a plane that includes the quill axis, but is not limited to this. Furthermore, the present invention is not limited to parallel links with equal opposite sides (FIG. 3). It is also possible to make the lengths of opposite sides slightly different. In Figure 4, the levers 15 and 16 are made equal and the movable link 19 is slightly longer than the fixed link 14' as a combination of links with equal opposite sides and links with slightly different opposite sides. By making the lever shown in FIG. 5 slightly longer than the lever 16 and shown in FIG. 6 with both the lever and link being different, the relationship between the tool trajectory and the tip of the quill can be arbitrarily selected and a wide range of possibilities can be accommodated. Furthermore, in normal use, the fixed link 14' and the moving link 19, which are defective in use, are equally connected to the lever 1.
Even if the lever 5 is made wider than the lever 16, it can be used by changing the angle of the fixed link and the quill axis (Fig. 7). When combined with the lever length selection described above, the compatible width can be greatly increased. It is something that can be expanded. In this way, by arbitrarily selecting the forming point locus of the forming tool, it has become extremely easy to design each type of coil spring.

Now, the link 19 extends beyond the two pivot points 17, 18 in both directions. The tool 20 is fastened to the extended end of the quill with its forming slope facing toward the quill. The coil body forming tool has a first forming slope and a second forming slope, and is attached to a mechanism that can adjust the deviation of the center of the forming groove along the slope on the second forming slope with respect to the quill axis. The other end of the extension is threaded with a stop bolt 21 that determines the forward end of the tool, and spring hooks 22 are provided protruding from both sides. A tension spring 23 is stretched between the spring hook 22 and a spring hook 24 protruding from the pedestal 14 closer to the quill.

The forming tool is therefore always biased towards the quill 13, and the virtual center of oscillation of the forming tool is located on the opposite side of the forming tool with respect to the center of said quill.
A U-shaped guide plate 25 having a top plate is fastened to both sides of the base 14 so as to sandwich the four-bar link, and the end face of the top plate serves as a stopper for the stop bolt 21. This four-bar link is moved forward and backward toward the front of the quill under the control of a cam to form a spring. That is, a rod 26 pivotally connected to the tip of the L-shaped lever 16 remote from the quill 13 is pivotally connected to a first crank lever 27 pivotally supported on the machine frame 1. On the other hand, on a cam shaft 28 which is supported on the machine frame 1, each cam 29 is arranged in correspondence with the tool in the axial direction at an angle at which each cam 29 sequentially performs its respective role by one revolution of the shaft. A second crank lever 30 is disposed on each cam and is pivotally mounted on the same axis. A cam follower 31 supported by the end of the second crank lever is pressed against the outer periphery of the cam. The free end of the second crank lever 30 is connected to the free end of the first crank lever 27 by a rod 32. On the other hand, the camshaft 28 is connected to a servo motor 34 via a reduction gear 33 by a transmission means such as a pulley or a gear. Further, a tachogenerator 35 for detecting the rotation speed of the servo motor 34 and a detector 36 for detecting the rotation angle of the camshaft are provided. Therefore, when the camshaft is rotated by the servo motor, the second crank lever 30 turns at the respective cam operating angles, and the four-bar link is released from the four-bar link via the rod 32, first crank lever 27, and rod 26. The link is swung toward the quill 13 by the action of the tension spring 23. The tool 20 advances to a required position on the front surface of the quill by this swinging motion, and required operations such as bending, coiling, cutting, etc. are performed with the required tool at the desired time. In FIG. 2, only the support mechanism for tool No. 3 is illustrated. Although the same support device is used as a unit for other tools, it is not necessarily necessary to use it for the support mechanism of all tools, and it may be sufficient to use it only for the support mechanism of one tool, for example, a coil body forming tool. be.

(C) Control System The present invention uses a system in which the above-described servo motor 9 for driving the feed roller and servo motor 34 for driving the cam are controlled in conjunction with each other in the above configuration, and these are controlled by a computer attached numerical value. Controlled by a control device. This control circuit will be explained below with reference to FIG. A keyboard 40 for selecting address words and inputting numerical values and a mode change/start/stop switch 41 are connected to an interface 42.
computer (hereinafter referred to as CPU) 43 via
Enter. An interrupt circuit 44 that specifies the sampling time is also connected to the CPU via an interface 42.
Enter. When there is an input from the keyboard 40, the keyboard input is interrupted by an interrupt circuit 44. Further, the input to the switch 41 is input only when there is an interrupt input. On the other hand, when there is an interrupt input, the CPU 43 displays the current value on the display 45, and also inputs and stores the value from the keyboard 40 into the memory 46. When the switch 41 is activated, necessary information is read out from the command information stored in the memory 46, instantaneous values are calculated according to the program, and functions for control are generated. This function is executed by the interface 4 by the input of the interrupt circuit 44.
A driving voltage is outputted to the drive unit 48 of the feed-out roller 4 via the feed-out roller 7 to rotate the drive servo motor 9 of the feed-out roller. This rotation is TG1
0 is fed back to the drive unit 48 and speed control is performed. The detector 11 connected to the TG sends its output via the interface 47.
Input to CPU43. The current value from the detector and
The current value calculated from the command value is calculated in the CPU and controlled so that the difference between them is zero. On the other hand, the drive unit 49 of the camshaft 28 is controlled in the same way, and the current value from the detector 36 is input to the CPU 43, and the current value calculated from the command value is compared with the current value and controlled so that the difference becomes zero. It is. Depending on how the program is constructed, it is possible to simultaneously control the rotation of the camshaft and the feeding of the wire by the feed roller.
With this configuration, the relationship between each part in the manufacturing process of the irregularly shaped spring shown in FIG. 9, the state of the tool based on information from the CPU, and the state of feeding out the strands will be explained.
The movement of the cam according to the program in Figure 10 is as follows.
This will become clearer by referring to the rotation angle of the camshaft and the cam position in the figure. In other words, the straight line part A is sent out at 30 m/min with the command sequence number N1, wire feed amount Z4.0, wire feed speed F30, and stops at 4 mm where the value of the detector 11 and the value calculated from the command value by the CPU 43 match. I am made to do so. (Figure 12)
At the following bending part B, the command N2 is C20.0, and the camshaft 28 is rotated at 30 rpm of N1, and the value of the detector 36 and the CPU
It will be stopped at the 20 degree position where the value calculated from the command value matches. As a result, the No. 2 cam is rotated to the operating position and the cam follower 31 is released.
The series of movements of the second crank lever 30, rod 32, first crank lever 27, and rod 26 becomes free, and the second four-bar link is rotated by the tension of the tension spring 23, and the forming tool 20 advances to the front of the quill. . Directive N3 Z0.8 and the length of the strand is 0.8mm
It is sent out at a speed of 30m/min and diagonally downward to the left at a 45 degree angle.
It can be bent 90 degrees (Figure 13). In the following straight line C, the camshaft is rotated at 30 rpm to the 40 degree position at command N4 C40.0, the No. 2 cam is rotated to the inoperative position, and the No. 2 forming tool is moved backward. At Z5.0 of command N5, the strand is fed out for 5 mm at a speed of 30 m/min (first
Figure 4). At the following bending part 2, the camshaft is rotated to the 60 degree position by command N6 C60.0. This rotates cam number 1 to the operating position. The first four-bar link operatively connected to this cam is pivoted by the action of tension spring 23 to advance the forming tool to the front of the quill. At Z0.8 of command N7, the strand is fed out 0.8 mm at a speed of 30 m/min and bent 90 degrees to the left on the forming surface of the No. 1 forming tool (Fig. 15).The following straight line is C80 of command N8. At 0 the camshaft is rotated to the 80 degree position at 30r.pm. At this time, the No. 1 cam is rotated to the inoperative position and the No. 1 forming tool is retracted. With command N9 Z10.0, the wire is 10mm at a speed of 30m/min
(Fig. 16). For the subsequent coil body, the camshaft is rotated to the 100 degree position by command N10 C100.0. Next command N11 G1・
With C160.0 and Z120.0, the camshaft starts moving from 100 degrees to 160
Stop at degree. During this time, the strands are fed out as the camshaft begins to move, stop together with the camshaft, and are fed out a length of 120mm. The 30rpm rotation of the camshaft is automatically changed by the linear interpolation function of G1. That is, as the No. 3 cam rotates, the forming tool faces downward from directly above, the distance between the forming surface passing through the front surface of the quill (Fig. 17) and the front end of the quill increases, and the forming tool collides with the first forming slope and the second forming slope. The bending radius of the mating strands gradually increases, and the formed coil body is formed into a tapered shape (FIG. 18). For the next straight line, the command N12 C180.0 returns the camshaft to S30.
It is rotated to the 180 degree position at 30 rpm and the No. 3 cam is rotated to the inactive position. At Z10.0 of command N13, the wire is fed out at a speed of 10 mm at 30 m/min (first
Figure 9). At the next bending part, the camshaft is rotated to 200 degrees with command N14, C200.0, and cam No. 7 is rotated to the operating position. As a result, the No. 7 forming tool is directed upward from the bottom and advances to the front of the quill. Directive N15
At Z0.8, the wire is fed out 0.8 mm at a speed of 30 m/min, collides with the forming surface, and is bent 90 degrees upwards (20th
figure). The following straight line is command N16, C220.0, and the camshaft is rotated to the 220 degree position. This causes the No. 7 cam to be rotated to the inoperative position and the No. 7 forming tool to be retracted. At Z5.0 of command N17, the strand is fed out by 5 mm (Fig. 21). The following bending part is command N.
At C240.0 of 18, the camshaft is turned to the 240 degree position.
This turns the No. 5 cam to the operating position and the No. 5 forming tool faces from left to right and advances to the front of the quill. At Z0.8 of command N19, the wire is fed out 0.8 mm, collides with the molding surface, and is bent 90 degrees to the right (second
Figure 2). The following straight line is N20 C260.0 and the camshaft is
Rotated to 260 degree position. This causes the No. 5 cam to be rotated to the inoperative position and the No. 5 forming tool to be retracted. At Z4.0 of command N21, the wire is fed out by 4 mm (Fig. 28). The following bending part O is command N2
2 C280.0 rotates the camshaft to the 280 degree position.
As a result, the No. 4 cam is rotated to the operating position, and the No. 4 forming tool advances toward the front of the quill from the upper left to the lower right. Directive N28 Z0.8 and wire is 0.8mm
The straight line that follows is sent out, collides with the molding surface, and is bent 90 degrees to the lower right (Fig. 24).The camshaft is rotated 300 degrees at C300.0 of N24. This causes the No. 4 cam to be rotated to the inoperative position and the No. 4 forming tool to be retracted. At Z4.0 of command N25, the wire is fed out by 4 mm (Fig. 25). Cutting is done according to command N26.
In C360.0 the camshaft is rotated 360 degrees or to the starting position. During this rotation of the camshaft, cam No. 6 passes through the operating position and returns to the non-operating position. By this 6
The cutting tool No. 1 passes through the front of the quill during its swing and cuts the wire. This one-step operation completes the molding of one special spring. In this embodiment, only the coil body is equipped with the linear interpolation function of G1 to perform simultaneous two-axis control. Of course, two-axis control can also be easily performed.

As detailed above, the tool support mechanism is not a lever mechanism with one fulcrum, but a four-bar link mechanism with two fulcrums, that is, one link fixed, and is provided on a radius around the quill, so the virtual fulcrum of the tool is can be taken on the same side as the quill. Also, since it is a four-bar link mechanism, it is possible to create a shape that does not take up much width in a plane parallel to the quill axis. These effects also allow a large number of tool support devices to be arranged radially around the quill, making it possible to produce many types of springs regardless of the spring type. In addition, simultaneous two-axis control is achieved using the cam shaft, feed roller shaft, and computer-equipped numerical control device, so even if the spring shape is changed, the standard cam can be used without replacing the cam in charge, and the program can be changed. be able to. Furthermore, simultaneous two-axis control has a number of features, such as not only the special shape of the coil body can be manufactured, but also the ability to eliminate wasted time and realize a significant increase in efficiency.

[Brief explanation of the drawing]

FIG. 1 is a front view mainly showing the arrangement of tools, cams, and a numerical control device. FIG. 2 is a side view showing a wire feeding mechanism, a No. 3 tool support mechanism, and a cam-related mechanism. 3 to 7 are diagrams showing the relationship between the tool trajectory and the quill end when the length relationship of the four-bar link is multiplied. FIG. 3 is a block diagram showing the control system. FIG. 9 is a diagram showing a special coil spring. Figure 10 is a process sheet for manufacturing the spring shown in Figure 9. FIG. 11 is a cam timing diagram. 12 to 25 are views showing the process of manufacturing the spring shown in FIG. 9 using the program shown in FIG. 10. FIG. 26 is a diagram showing a preferable range of the virtual fulcrum of the No. 3 tool. FIG. 27 is a diagram showing the positional relationship between the No. 3 tool and the quill end when making the small circular part and the large circular part. 4... Delivery roller, 9, 34... Servo motor, 10, 35... Tachozi generator, 11,
36...Detector, 13...Quill, 14'...Fixed link, 15, 16...L-shaped lever, 19...
... Link (motion), 20 ... Tool, 23 ... Tension spring, 26, 32 ... Rod, 27 ... First crank lever, 28 ... Camshaft, 29 ... Cam, 3
0...Second crank lever, 31...Cam follower, 40...Keyboard, 41...Switch, 4
2, 47...Interface, 43...CPU,
44...Interrupt circuit, 45...Display unit, 46...Memory, 48, 49...Drive unit.

Claims (1)

[Scope of Claims] 1. A plurality of forming tools attached to a tool mounting surface perpendicular to the quill that guides the strands fed out by a pair of feeding rollers are sequentially advanced from substantially perpendicular directions to the front surface of the quill. In a machine that manufactures a coil spring by changing the flow direction of the wire by abutting the wire, a four-bar link is provided on the tool mounting surface that is swingable with one link fixed on the radial line around the quill. The forming tool is provided on the quill side as an extension of the moving link on the opposite side of the fixed link of the four-bar link so that its forming surface faces the quill, and the forming tool is formed by swinging of the four-bar link. a cam-acting member operatively connected to swing the four-bar link, the fixed link being fixed such that the virtual center of swing of the quill is located on the opposite side of the forming tool with respect to the center of the quill; An automatic spring manufacturing machine characterized by being provided with. 2. The automatic spring manufacturing machine according to claim 1, wherein the four-bar link is a four-bar parallel link. 3. The automatic spring manufacturing machine according to claim 1, in which one or two pairs of four-bar links have unequal link lengths. 4. The automatic spring manufacturing machine according to claim 1, wherein the fixed link of the four-bar link is perpendicular to the quill axis. 5. The automatic spring manufacturing machine according to claim 1, wherein the fixed link of the four-bar link is inclined with respect to the quill axis. 6. The automatic spring manufacturing machine according to claim 1, wherein the four-bar link swings on a plane including the quill shaft. 7. The automatic spring manufacturing machine according to claim 1, wherein the four-bar link swings in a plane parallel to the quill axis. 8. The coil body forming tool among the plurality of forming tools has a first forming slope for forming a small circle at the base of the locking end of the spring and a second forming slope for forming the coil body; 2. The automatic spring manufacturing machine according to claim 1, wherein the forming slope is formed at a more acute angle than the first forming slope, and a forming groove is carved along the slope. 9. A plurality of forming tools attached to a tool mounting surface perpendicular to the quill that guides the strands to be fed out by a pair of feed rollers are sequentially advanced from substantially perpendicular directions to the front of the quill, and the tools abut against the strands. In a machine for manufacturing coil springs by changing the flow direction of the strands, one or more four-bar links are provided on the tool mounting surface and are capable of swinging with one link fixed on a radial line around the quill, The forming tool is provided on the quill side as an extension of the moving link on the opposite side of the fixed link of the joint link so that its forming surface faces the quill, and the virtual center of the swing of the forming tool due to the swing of the four-bar link is a cam-acting member operatively connected to swing the four-bar link; the cam-acting member being operatively connected to swing the four-bar link; A first servo motor for controlling the rotation angle of the cam action member by a command, a first detector for detecting the rotation angle of the cam action member, a second servo motor for controlling the rotation angle of the feed roller by a command, and the rotation of the feed roller. A second detector for detecting the feed length of the servo motor and a numerical control device capable of simultaneously controlling the first and second servo motors in a relational manner while receiving signals from the first and second detectors are combined. Automatic spring manufacturing machine.