Patent Application
20180071812
The present invention relates to a device for manufacturing a coil spring which manufactures a coil spring by using a long continuous material or a short material which is cut to a predetermined length, and a method for manufacturing the coil spring.
As a coiling machine suitable for manufacturing coil springs of various shapes in quantity, a coiling machine not having a mandrel is known. JP 11-197775 A (Patent Literature 1) or JP 2013-226584 A (Patent Literature 2) relates to an example of a coiling machine not having a mandrel. This type of coiling machine bends a material of a coil spring sent out from a distal end of a material guide in an arc shape by a first pin and a second pin, and also pitches the coil spring by a pitch tool. The positions of the first pin and the second pin are controlled based on a computer program stored in a control unit, and control data corresponding to a shape of the coil spring.
A long material (a continuous material) supplied continuously to the coiling machine is wound like a hoop so that it can be conveniently carried or stored. This continuous material is mounted on a reel of a continuous material mounting portion. By rotating the reel, a material of the coil spring is reeled out from the continuous material. The material reeled out is supplied to the coiling machine. By using the continuous material, a coil spring formed of the same type of material can be manufactured in quantity efficiently.
In the case of a coiling machine which uses the above-mentioned continuous material, if a material needs to be changed according to the type of the spring (wire diameter or steel type), the continuous material mounted on the continuous material mounting portion must be exchanged. Accordingly, it takes time and manpower to perform the preparation operation for the material exchange. For this reason, manufacturing of a coil spring which uses a hoop material is unsuitable for limited production of diversified products.
In order to manufacture a wide variety of coil springs in small quantities, using a material cut to a predetermined length in advance (i.e., a short material) is considered. However, in manufacturing a coil spring by the short material, it is necessary to perform a distal end portion shaping operation necessary at the time of starting the coiling for each coil spring. The distal end portion shaping operation has conventionally been performed by a worker who manually operates an actuator. In this manual operation, while a distal end portion of the material is moved toward the first pin, the distal end portion of the material is bent to some degree by moving the first pin. After that, the material is bent in an arc shape while moving the distal end portion of the material toward the second pin. These kinds of works require skill. Furthermore, performing the distal end portion shaping operation for each and every short material is extremely inefficient, and extra caution must be paid for safety. For such reasons, conventional techniques leave room for improvement.
Accordingly, an object of the present invention is to provide a coil spring manufacturing device capable of efficiently manufacturing a coil spring by using a long continuous material or a short material which is cut to a predetermined length, and a method for manufacturing the coil spring.
A coil spring manufacturing device according to one embodiment comprises a coiling machine, a continuous material feed portion, a straightener, a cutter, a short material mounting portion, and guide means (for example, a guide roller). The continuous material feed portion supplies a material reeled out from a continuous material wound like a hoop to the coiling machine. The straightener is disposed between the continuous material feed portion and the coiling machine, and corrects the material reeled out from the continuous material to be straight. The cutter is arranged at a downstream side of a movement direction of the material with respect to the straightener, and cuts the material. On the short material mounting portion, a short material cut to a predetermined length is mounted. The guide means supplies the material reeled out from the continuous material feed portion, or the short material taken out from the short material mounting portion to the coiling machine. An example of the continuous material feed portion includes a first continuous material mounting portion and a second continuous material mounting portion. On the first continuous material mounting portion, a first continuous material wound like a hoop is mounted. On the second continuous material mounting portion, a second continuous material wound like a hoop is mounted.
According to the present embodiment, a material reeled out from a long and hooplike continuous material mounted on a long material feed portion, or a short material taken out from the short material mounting portion can be selectively used according to need, and a plurality of kinds of coil springs can be manufactured efficiently.
An example of the coiling machine includes a material feed roller, a material guide, a first pin, a second pin, a pitch tool, a cutting tool, and a control unit. The material feed roller moves the material. The material is inserted into the material guide. The material which is sent out from a distal end of the material guide contacts the first pin. The second pin is disposed at a front side of a movement direction of the material with respect to the first pin. By bending the material between the first pin and the second pin, an arc portion is formed between the first pin and the second pin. The pitch tool is disposed at the front side of the movement direction of the material with respect to the second pin, and the material contacts the pitch tool. The cutting tool is disposed between the second pin and the pitch tool, and cuts the material between the cutting tool and the mandrel.
The control unit automates a distal end portion shaping operation of the material. The control unit includes means for advancing a distal end portion of the material toward the first pin, and detection means for detecting a position of the distal end portion of the material. Further, the control unit includes means for bending the distal end portion in a direction of approaching the mandrel by the first pin in a state in which the distal end portion reached the first pin, and means for forming a distal-end-side arc portion by bending the distal end portion between the first pin and the second pin.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the invention.
The coil spring 3 is manufactured by forming the material 2 spirally at a certain pitch (which may not be constant). The shape of the coil spring 3 can be various, and a coil diameter and a pitch, for example, may be changed according to the position of turns from an end. The coil spring may be formed in various shapes such as a cylindrical coil spring, a barrel-shaped coil spring, an hourglass coil spring, a tapered coil spring, a variable pitch coil spring, or a coil spring having a negative pitch portion.
The coil spring manufacturing device 1 according to the present embodiment includes a continuous material mounting portion 4 which functions as a continuous material feed portion W, a straightener 7, a cutter 8 (for example, a cutting grinder), a short material mounting portion 9, guide rollers 9a which function as guide means, a coiling machine 10, etc.
On a reel of the continuous material mounting portion 4, a continuous material 2A is mounted rotatably about a vertical axis. The continuous material 2A is composed of a long material 2 wound like a hoop. The continuous material 2A may be referred to as a hoop material. The continuous material 2A is a heavy load which may weigh several tons in some cases, and the entire length of the material 2 which is unwound may be several hundred meters or more.
The continuous material 2A wound like a hoop has more or less of a bend. For this reason, the material 2 which is reeled out from the continuous material 2A is corrected to be straight by the straightener 7. By cutting the continuous material 2A corrected to be straight by the cutter 8, a short material 2′ of a predetermined length (for example, several meters or so) is obtained. The cutter 8 is arranged at a downstream side of a movement direction of the material 2 with respect to the straightener 7. The short material 2′ obtained by the cutting is mounted on a material stand of the short material mounting portion 9.
The coil spring manufacturing device 1 of the present embodiment (
Further, the continuous material 2A is supplied to the coiling machine 10 via the guide rollers 9a. The coiling machine 10 manufactures the coil spring 3 by forming the supplied continuous material 2A into a helical shape. For example, the material 2 which is reeled out from the continuous material 2A passes by the cutter 8 (without having the material 2 cut), and is supplied to the coiling machine 10. The structure and the operation of the coiling machine 10 will be described later.
The coil spring manufacturing device 1 (
On the first continuous material mounting portion 4, a first continuous material 2A (a first hoop material) composed of a long material 2 wound like a hoop is mounted. Also on the second continuous material mounting portion 5, a second continuous material 2B (a second hoop material) composed of long material 2 wound like a hoop is mounted. The first continuous material 2A and the second continuous material 2B may be different from each other in terms of the type (wire diameter or steel type) or the same as each other. The first continuous material mounting portion 4 and the second continuous material mounting portion 5 serve as continuous material feed portions W.
Conversely, the operation can be switched from a mass production state of the coil spring using the second continuous material 2B (
As described above, according to the coil spring manufacturing device 1A of the present embodiment, a coil spring can be manufactured by alternately switching the continuous materials (the first continuous material 2A and the second continuous material 2B) which are different from each other in their types. More specifically, of the first continuous material mounting portion 4 and the second continuous material mounting portion 5, preparation of the material (an initial setup operation) can be carried out by using the spare time of the continuous material mounting portion not being used. Consequently, two types of coil springs can be manufactured efficiently.
A third continuous material mounting portion 6 may be provided, as shown by a two-dot chain line in
In step ST2, as the continuous material, which is supplied to the cutter 8, is cut to a predetermined length by the cutter 8, the short material 2′ is manufactured. The short material 2′, which is the material cut to the predetermined length, is mounted on the material stand of the short material mounting portion 9 in step ST3. In step ST4, when it is determined that a predetermined number of short materials 2′ have been stocked, supply of the continuous material is stopped in step ST5, and the manufacturing of the short material is finished.
Each of
In step ST13 of
When it is determined that the short material 2′ is to be used in step ST13, the process proceeds to step ST15. In step ST15, the short material 2′ mounted on the short material mounting portion 9 is supplied to the coiling machine 10 one by one via the guide rollers 9a.
The shape of the coil spring 3 formed by the coiling machine 10 is inspected in step ST21 of
When it is determined that the spring shape is acceptable in step ST21, steps such as a strain relief annealing step (step ST23), a first setting step (step ST24), a shot peening step (step ST25), and a second setting step (step ST26) are carried out. Only one of the first setting step (step ST24) and the second setting step (step ST26) may be carried out. The strain relief annealing step (step ST23) is carried out in order to eliminate a processing strain of the coil spring produced by cold working. In step ST23, the coil spring is heated by using a heating furnace, for example.
In step ST27, characteristic of the spring is inspected, and if the characteristic of the spring is acceptable, the process proceeds to step ST28. In step ST28, when it is determined that a predetermined number of coil springs have been manufactured, coil spring manufacturing is finished. If the predetermined number of coil springs are not obtained, the process returns to step ST20 and the coil spring manufacturing is continued.
In step ST27, if the characteristic of the spring is determined as not being acceptable, the process proceeds to step ST29. In step ST29, the manufacturing condition, etc., is adjusted, and the process returns to step ST20 to perform the coiling again.
As described above, the present embodiment includes the first continuous material coiling process, the second continuous material coiling process, and the short material coiling process. In the first continuous material coiling process, by supplying the material reeled out from the first continuous material 2A to the coiling machine 10, the coil spring is manufactured. In the second continuous material coiling process, by supplying the material reeled out from the second continuous material 2B to the coiling machine 10, the coil spring is manufactured. In the short material coiling process, by supplying the short material 2′ to the coiling machine 10, the coil spring is manufactured. By switching among the first continuous material coiling process, the second continuous material coiling process, and the short material coiling process as needed, producing a certain type of coil springs in large quantity or producing a wide variety of coil springs in small quantities can be carried out efficiently.
The structure and the operation, etc., of the coiling machine 10 will be described by referring to
The coiling machine 10 includes a material guide 12 into which the material 2 is inserted, a first pin 13, and a second pin 14. The material 2 sent out from a distal end 12a of the material guide 12 contacts the first pin 13 first. The material 2 bent by the first pin 13 contacts the second pin 14. On outer peripheral portions of the first pin 13 and the second pin 14, circumferentially continuous grooves 13a and 14a are formed, respectively. Each of the first pin 13 and the second pin 14 of the present embodiment is a roller member rotatable about an axis. In another embodiment, each of the first pin and the second pin may be a pin member which does not rotate.
The coiling machine 10 includes a pitch tool 15, a cutting tool 16, and a mandrel 17 having a receiving blade 17a. The pitch tool 15 is arranged at a front side of a movement direction of the material 2 with respect to the second pin 14. As the material 2 bent by the second pin 14 contacts the pitch tool 15, the coil spring is pitched. The cutting tool 16 includes a blade portion 16a. When the cutting tool 16 is moved in a direction indicated by arrow Z1 (
Further, the coiling machine 10 includes a sensor 18 and a material rotation apparatus 20. The sensor 18 functions as detection means for detecting a position of a distal end portion 2a (
The pinch roller unit 21 includes pinch rollers 21a and 21b, an actuator 26 (
The first pin 13 is disposed at the front side of the movement direction of the material 2 with respect to the distal end 12a of the material guide 12 (i.e., at the downstream side of the movement direction). The second pin 14 is disposed at the front side of the movement direction of the material 2 with respect to the first pin 13. The material 2 sent out from the distal end 12a of the material guide 12 toward the first pin 13 is bent between the material guide 12 and the first pin 13 with the distal end 12a of the material guide 12 being a substantial bend starting point.
In the ROM 42, a program for controlling the CPU 40 and various kinds of fixed data are stored. The RAM 43 includes a memory area in which various kinds of data, etc., necessary for forming a coil spring is stored. The communication interface portion 44 controls data communication performed with external devices through a communication line (a network). The display/operation driver 45 controls a display operation portion 55 comprising a display (a display panel). By operating the display operation portion 55, information necessary for forming the coil spring can be stored in the memories such as the RAM 43.
The material feeding driver 46 controls a motor 60 for rotating the material feed rollers 11a and 11b. The first pin moving driver 47 controls a first pin drive mechanism 61 comprising an actuator for driving the first pin 13. The second pin moving driver 48 controls a second pin drive mechanism 62 comprising an actuator for driving the second pin 14. The pitch tool driver 49 controls a pitch tool drive mechanism 63 comprising an actuator for driving the pitch tool 15. The cutting tool driver 50 controls a cutting tool drive mechanism 64 comprising an actuator for driving the cutting tool 16. The pinch roller rotation driver 51 controls the actuator 26 of the pinch roller unit 21. The mandrel moving driver 52 controls a mandrel moving actuator 65 for moving the mandrel 17 (up and down, for example). The rotation mechanism driver 53 controls an actuator of the rotation mechanism 25.
The electrical structure including the CPU 40 of the coiling machine 10 includes, for example, a control circuit for controlling the rotation of the rollers 11a and 11b, a control circuit for controlling the pin drive mechanisms 61 and 62, a control circuit for controlling the pitch tool drive mechanism 63, and a control circuit for controlling the cutting tool drive mechanism 64. These control circuits function as a control unit 70 which controls the operation or the like of the coiling machine 10. The control unit 70 controls the pin drive mechanisms 61 and 62 such that the positions of the first pin 13 and the second pin 14 are changed in accordance with shape data (for example, a coil diameter) of the coil spring that has been input.
A personal computer 80 can be connected to the control unit 70 of the present embodiment through the communication interface portion 44. The personal computer 80 includes a display unit 81 including a display panel, an input operation portion 82 including a keyboard, a pointing device 83 such as a mouse, etc. The personal computer 80 includes a storage medium 84 which is removably attached, if necessary.
Hereinafter, a distal end portion shaping operation will be described by referring to
In step S1 of
In step S2 of
In step S4 of
In step S5, the material 2 sandwiched between the material feed rollers 11a and 11b is moved toward the first pin 13, as shown in
It is assumed that positions of the first pin 13 and the second pin 14 are separated from each other by distance G in a direction along axes X2 and X3 of the pins, as shown in
As shown in
In contrast, in the case of the present embodiment, the material 2 is rotated about axis X1 by the pinch rollers 21a and 21b. More specifically, in a state in which the distal end portion 2a of the material 2 is bent by the first pin 13, as shown in
The above operations are carried out in steps S6 and S7 of
As the material 2 is rotated about axis X1, the distal end portion 2a of the material 2 is inclined by angle θ as shown in
In step S8 of
By moving the material 2 further by the material feed rollers 11a and 11b, as shown in
After the distal-end-side arc portion 2b′ of a predetermined shape has been formed, by moving the cutting tool 16 toward the receiving blade 17a as shown in
When the scrap portion 2x is cut off, the distal-end-side arc portion 2b′ is left. The distal-end-side arc portion 2b′ constitutes a part of the coil spring (i.e., an end turn portion). After the above process, by continuously moving the material 2 by the material feed rollers 11a and 11b, the coil spring 3 is formed (coiled). More specifically, the material 2 discharged from the distal end 12a of the material guide 12 is moved toward the second pin 14 via the first pin 13. As the material 2 is formed in an arc shape by the first pin 13 and the second pin 14, an arc portion 2b is formed continuously as shown in
After a radius of curvature of the arc portion 2b is minimized between the first pin 13 and the second pin 14, the radius of curvature gradually increases as the arc portion 2b approaches the pitch tool 15 because of a springback effect. Accordingly, considering the springback effect, a position of the second pin 14, etc., is controlled. When one coil spring is formed, by the operation of the cutting tool 16, a rear end of the coil spring (a front end of a coil spring to be formed next) is cut. When a continuous material such as the first continuous material 2A or the second continuous material 2B is used, forming of the next one coil spring is performed continuously. When the short material 2′ is used, a coil spring of a number corresponding to the length of the short material 2′ (for example, one) is formed.
As described above, a method of shaping a distal end portion of a coil spring of the present embodiment includes the following steps automated by the control unit 70:
(1) Moving the material 2 toward the material guide 12;
(2) Detecting the position of the distal end portion 2a of the material 2 which has been sent out from the material guide 12;
(3) Moving the mandrel 17 toward the second position;
(4) Bending the distal end portion 2a in a direction of approaching the mandrel 17 by the first pin 13;
(5) Moving the mandrel 17 to the first position;
(6) Moving the material feed rollers 11a and 11b to the unclamping position;
(7) Rotating the material 2 about axis X1 so that the distal end portion 2a of the material 2 is directed toward the groove 14a of the second pin 14;
(8) Moving the material feed rollers 11a and 11b to the clamping position;
(9) Moving the material 2 by the material feed rollers 11a and 11b, thereby placing the distal end portion 2a in the groove 14a of the second pin 14;
(10) Forming the distal-end-side arc portion 2b′ by bending the material 2 between the first pin 13 and the second pin 14; and
(11) Cutting off the scrap portion 2x ahead of the distal-end-side arc portion 2b′ by the cutting tool 16.
Needless to say, in carrying out the present invention, the form such as the structure and arrangement of each of the elements which constitute the coil spring manufacturing device, including the continuous material mounting portion on which a continuous material such as a hoop material is mounted, the short material mounting portion, the straightener, and the cutter, may be modified variously if necessary. For example, for the guide means for guiding the material to the coiling machine, a guide member having a shape different from the guide rollers 9a may be used. Further, as a matter of course, constituent elements of the coiling machine such as the first pin and the second pin, the pitch tool, and the cutting tool can also be modified variously in embodying the present invention, if necessary.
Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2015-113849 | Jun 2015 | JP | national |
This application is a Continuation Application of PCT Application No. PCT/JP2016/061705, filed Apr. 11, 2016 and based upon and claiming the benefit of priority from prior Japanese Patent Application No. 2015-113849, filed Jun. 4, 2015, the entire contents of all of which are incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2016/061705 | Apr 2016 | US |
| Child | 15818316 | US |
