JP2019025526A - Manufacturing method and manufacturing apparatus for arc-shaped coil spring - Google Patents

Abstract

To provide, in a manufacturing method and manufacturing apparatus for an arc-shaped coil spring using a servo press, specific technical means by which the coil spring can be manufactured in a continuous operation in one direction without changing a feed direction with respect to an operation of a pressing member by focusing on a clamp structure in order to solve a remaining object, which is to shorten a manufacturing time.SOLUTION: A manufacturing method for an arc-shaped coil spring comprises a clamping step, an end detection step, a rotation angle positioning step, a pitch feed step, and a pressing-member driving step. Using a clamp having a claw part whose leading end is bent downward into an L-shape, the claw part is sandwiched and fixed between effective line diameters by which first and second numbers of effective winds are obtained from the seat surface of one side of a straight cylindrical coil spring. Pressing-member is driven by a servo press. Each operation in the pitch feed step and the pressing-member driving step employs a configuration in which speed control and position control are exerted, thereby molding an arc-shaped coil spring having an arbitrary curvature.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an apparatus for manufacturing an arc-shaped coil spring, and more particularly, to a device for manufacturing a coil spring having an arc-shaped curvature by pressing a pressing member against a coil spring processed into a straight tube shape and plastically deforming it. It is related with the technique which detects the information for detailed control by this, and raises the processing precision by sequence control based on the detected information concerned.

  Arc coil springs are used in automobile automatic transmission clutches, etc., and absorb shocks and vibrations that occur when the clutch is engaged and disengaged, as well as minute fluctuations in the rotational output of the prime mover. It plays an important role in a rotational power transmission system having a clutch structure.

  Also, in the automobile industry, the demand for clutch parts, such as combined use with motors in hybrid cars, is not only high in performance, such as increased performance and small torque, but also can withstand these demands. There is a need for an arc coil spring.

  The requirements for such arc-shaped coil springs are that the ground surfaces of both ends of the arc-shaped coil spring are perpendicular to the rotation axis, and the shortest portion of the coil spring wire is located at a predetermined angle on the ground surface. Specific requirements for product specifications based on solution of problems at the manufacturing stage such as arc-shaped coil springs that are not twisted, non-uniformly spaced springs, and suitable expansion and contraction operations when arc-shaped coil springs are expanded There is a current situation.

  Originally, the production of a straight cylindrical coil spring is an industrially wide and general technique, and it is necessary to produce a product with a high yield in accordance with the manufacturer's specifications. On the other hand, as a method of manufacturing an arc-shaped coil spring, there are many methods of manufacturing from a straight cylindrical coil spring, and various mass production techniques have been developed.

  Specifically, for example, the name of the invention “Method of manufacturing an arc spring for a clutch disk” has been disclosed, and has already been publicly known (see Patent Document 1). This technology is intended to form an arc-shaped coil spring without applying excessive force, and a technique related to a heat treatment process for fitting a plurality of arc-shaped springs for torque transmission to arc-shaped grooves. The technical field for manufacturing the arc-shaped coil spring according to the present invention is common. However, the invention according to Patent Document 1 includes a plurality of processes such as a tempering process, a tempering process such as shot peening, and a low temperature temper process, and the straight cylindrical coil spring is formed in the shape of an arched groove. The change in curvature and the curvature itself cannot be changed, and it is not possible to deal with unequal spacing springs.

  Patent Document 2 discloses a technique in which the title of the invention is “an apparatus for manufacturing an arc coil spring”. Specifically, "a semi-cylindrical fixed bracket that holds a linear coil spring straddling the inner peripheral surface, and a coil spring arranged in parallel horizontally along the axis above the inner peripheral surface. A pair of movable movable metal fittings that are curved, a pair of movable walls that are slidably inserted into and retracted into the fixed receiving metal fittings, and are in contact with both end surfaces of the coil spring, and an axial direction along the outer wall of the fixed metal receiving metal fittings A pair of extending fixed plates and a plurality of fixing bolts screwed to the fixing plates are provided. The fixing plates are positioned and fixed by the fixing bolts on the end side, and the fixing bolts at the center are in contact with the movable wall, It is pushed into the metal fitting side to protrude from the inner peripheral surface, and the end of the coil spring is further curved. However, although it is possible to manufacture a plurality of them at the same time, it has not yet been possible to freely distribute the curvature with respect to the position of the number of turns. Therefore, it is difficult to arbitrarily provide a structure that exhibits a resonance prevention effect.

  Patent Document 3 discloses a technique in which the name of the invention is “an apparatus for manufacturing an arc coil spring”. Specifically, “the coil spring is provided with a fixed receiving metal fitting corresponding to the arc-shaped coil spring, a movable pressing metal fitting, and a drive unit, and the distance between the movable pressing metal fitting and the fixed metal fitting is held by the lock arm. It is "low temperature annealed". This technique also relates to an apparatus for manufacturing an arc coil spring having a curvature as in the present invention. However, the effect of the present invention that the coil spring has a change distribution of the spring characteristics has not been achieved.

  Patent Document 4 discloses a technique in which the title of the invention is “a method and an apparatus for manufacturing a coil spring”. Specifically, “a coil spring comprising a clamping step of clamping a part of a straight cylindrical coil and a repeating step of continuously performing a pitch dimension adjusting step and forming the straight cylindrical coil into a curved coil spring. Manufacturing method ". This technique also relates to an apparatus for manufacturing an arc coil spring having a curvature as in the present invention. However, the effect of the present invention that the coil spring has a change distribution of the spring characteristics has not been achieved.

  Therefore, in any of Patent Document 1 to Patent Document 4, the present invention solves the problems, and the change in the operation speed and the feed amount are finely controlled by using a servo press or the like in order to obtain a free curvature and high accuracy. There is no description or suggestion of possible technologies.

  In addition, in order to solve the above problems, the present inventor has obtained a patent for a technique whose title is “a manufacturing method and a manufacturing apparatus of an arc coil spring” (Patent Document 5). Specifically, “from a clamping process for fixing a straight cylindrical coil spring, an end detection process for detecting an end, a rotation angle positioning process, a pitch feeding process, a pressing member driving process, and a driving direction changing process. It is configured, and the operation of pushing the pressing member downward from the pitch between the pitches is continuously repeated to transform from a straight cylindrical shape into a coil spring having a curvature. However, according to such a technique, the process of changing the feeding direction by changing the coil spring to be processed is included in the process of forming the whole in an arc shape. Therefore, it can be said that the problem of shortening the manufacturing time remains.

JP 2000-129359 A JP 2014-231069 A JP 2014-223656 A Japanese Patent Laid-Open No. 11-019743 Japanese Patent No. 6113891

  In order to solve the remaining problem of shortening the manufacturing time in the manufacturing method and the manufacturing apparatus of the arc-shaped coil spring using the servo press already patented by the present inventor, the present invention has a clamp structure. Attention is focused on providing technology for reducing the processing time by increasing the operating speed of the pressing member and making it possible to manufacture with continuous operation in only one direction without switching the feed direction with respect to the operation of the pressing member. It is what.

  The present invention is a method of manufacturing a coil spring having a curvature from a straight cylindrical shape, a clamping step for fixing the straight cylindrical coil spring, an end detection step for detecting an end portion, a rotation angle positioning step, a pitch The clamping step includes a clamp having a claw portion whose tip is bent downward in an L shape, and the claw portion is arranged on one side of the straight cylindrical coil spring. The straight cylindrical coil spring is obtained by sandwiching and fixing between the effective wire diameters which are the first and second effective turns from the seating surface, so that the end detection step obtains positional information as an operation reference of the pitch feeding step. The position of the end of the straight cylindrical coil spring is adjusted by rotating the contact surface of the end to which the straight cylindrical coil spring is fixed, and the pitch feeding step The position where the pressing member driving process is started and the straight cylindrical coil spring is moved to an appropriate position during the pressing member driving process, and the pressing member driving process drives the pressing member from above to the pitch and pulls back upward. The operation is repeated between adjacent pitches by controlling a servo press, and each operation in the pitch feeding step and the pressing member driving step is arc-shaped having an arbitrary curvature by performing speed control and position control. A means for forming a coil spring is employed.

  Further, in the present invention, each operation necessary in each step from the end detection step to the pressing member driving step is performed from any one of a photoelectric sensor, an image sensor, a contacted sensor, a proximity sensor, or a combination thereof. You may employ | adopt the means controlled based on the acquired position and shape information.

  Further, the present invention is a manufacturing apparatus for manufacturing a coil spring having a curvature from a straight cylindrical shape, a clamp mechanism for fixing the straight cylindrical coil spring, an end detection mechanism for detecting an end portion, and a rotation angle positioning mechanism, The clamp mechanism is composed of a pitch feed mechanism and a pressing member driving mechanism, and the clamp mechanism uses a clamp having a claw portion whose tip is bent downward in an L shape, and the claw portion is formed by the straight cylindrical coil spring. The end detection mechanism is inserted in between the effective wire diameters corresponding to the first and second effective turns from the seating surface on one side and fixed, and the end detection mechanism is used to obtain position information as an operation reference of the pitch feed mechanism. Position information of the end of the straight cylindrical coil spring is detected, and the rotation angle positioning mechanism rotates the straight cylindrical coil spring fixed by the clamp mechanism so that a contact surface is provided. The pitch feed mechanism moves the straight cylindrical coil spring to an appropriate position at the start of the operation of the pressing member driving mechanism and the pressing member driving mechanism, and the pressing member driving mechanism The pressing member is driven between the pitches from above, and the operation of pulling back upward is repeatedly performed, and the servo press is used for the operation for deforming from the straight cylindrical shape to the arc-shaped coil spring having the curvature, You may employ | adopt the structure shape | molded in the shape which has arbitrary curvatures by controlling each operation | movement in a pressing member drive mechanism to a respectively suitable speed and position.

  Further, according to the present invention, the necessary operations in each of the end detection mechanism, the rotation angle positioning mechanism, the pitch feed mechanism, and the pressing member driving mechanism are a photoelectric sensor, an image sensor, a contact sensor, and a proximity sensor. A configuration controlled based on position and shape information obtained from each of these sensors or a combination of these sensors may be adopted.

  According to the arc coil spring manufacturing method and apparatus according to the present invention, it is possible to cause plastic deformation at high speed and with high accuracy at every winding interval of the coil spring. It is possible to obtain an excellent coil spring.

  Moreover, according to the manufacturing method and manufacturing apparatus of the arc-shaped coil spring according to the present invention, the excellent effect of being able to process not only a constant curvature but also a shape having a different curvature stepwise or partially. Play.

It is a flowchart figure which shows the procedure of the manufacturing method of the arc-shaped coil spring which concerns on this invention. It is rotation positioning explanatory drawing of the contact surface which concerns on the edge part of the arc-shaped coil spring which concerns on this invention. It is a whole block explanatory view of the straight cylindrical coil spring concerning the present invention. It is processing state explanatory drawing of the manufacturing method of the arc-shaped coil spring which concerns on this invention. It is operation | movement explanatory drawing in the press member driving process based on this invention. It is pitch angle explanatory drawing of the arc-shaped coil spring which concerns on this invention. It is an attachment state adjustment explanatory view of the press member concerning the present invention. It is explanatory drawing which shows the place which detects the positional information by the sensor which concerns on this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing of the whole structure of the manufacturing apparatus of the arc-shaped coil spring which concerns on this invention.

  An arc-shaped coil spring manufacturing method and manufacturing apparatus according to the present invention is an addition of sensor technology to a technique related to an arc-shaped coil spring manufacturing method and manufacturing apparatus invented by the present inventor and already patented. Therefore, the operation of the pressing member with respect to the workpiece can be performed more precisely and accurately, and the reciprocating operation can be shortened compared to the conventional apparatus by making it possible to confirm the deformation state after the processing. In order to make it possible to complete the process, the greatest feature is that a clamp method which has not been used in the past is adopted and the pressing operation of the pressing member is performed using a servo press. Hereinafter, description will be given based on the drawings. Note that the overall shape of the arc-shaped coil spring and the manufacturing apparatus according to the present invention and the shape of each part are not limited to the description given below, but are within the scope of the technical idea of the present invention, that is, the same. It can change within the range of the shape and dimension which show | plays an effect.

  FIG. 1 is a flowchart showing a basic procedure of a manufacturing method 1 of an arc-shaped coil spring according to the present invention, and shows a flow of the entire work. Specifically, the arc-shaped coil spring manufacturing method 1 includes a clamping process A, an end detection process B, a rotation angle positioning process C, a pitch feed process D, and a pressing member driving process E.

  The clamping process A is a process of fixing the straight cylindrical coil spring 20. As the fixing means, a clamp 51 having a claw portion 52 whose tip is bent in an L-shape is used. The clamp 51 has a claw portion 52 that is a part of the contact surface 13 of the seating surface on one side of the straight cylindrical coil spring 20. Insert and fix between the second and second effective number of turns.

  The end detection step B is a step of detecting the arrangement state of the contact surface 13 where the end surface of the end portion 11 is in surface contact using the end detection mechanism 60.

  The rotation angle positioning process C is a process of adjusting the rotation position to a predetermined rotation position from the arrangement state of the contact surface 13 detected by the end detection process B.

  The pitch feed process D is a process of moving from the position where the pressing member 91 is driven continuously to the position where the pressing member 91 is driven to the end after the rotation positioning process C toward the end portion 11. is there.

  The pressing member driving step E is a step of performing a process of plastically deforming the pressing member 91 by pressing the pressing member 91 between the pitches 15 of the coil springs 10 within the range of the pitch feeding step D to leave a permanent strain.

  FIG. 2 is an explanatory view of rotational positioning of the contact surface 13 related to the end portion 11 of the arc-shaped coil spring 30 according to the present invention. As shown in FIGS. 2A to 2C, when the end surface of the coil spring 10 is polished, a contact surface 13 on which a glossy portion that looks like a substantially crescent shape contacts a holder or the like is formed. (Hereinafter, this surface is referred to as “contact surface 13”). In the arc-shaped coil spring 30, the surfaces that transmit the spring force of the spring are both ends of the coil. In FIGS. 2 (a) to 2 (c), the one-side polished surface and It is necessary to specify the rotation angle at which the end of the wire is arranged, and it is shown so that the difference in the angle at which processing starts by rotating to be located at the specified position can be compared It is.

  When the arc-shaped coil spring 30 after being processed is used, the contact surface 13 is not a point contact or a line contact but a surface contact as much as possible in a contact portion for transmitting an expansion / contraction force by the spring. It is desirable. Therefore, the cut surface cut in the middle of the effective length of the coil spring 10 has a substantially crescent shape, but the cut surface is not always perpendicular to the axis before the processing of the straight cylindrical coil spring 20, such as a holder. It may be necessary to provide a predetermined angle for abutting.

  FIG. 3 is an explanatory diagram of the overall configuration of the straight cylindrical coil spring 20 according to the present invention. FIG. 3 is a basic configuration explanatory view showing a basic configuration of the straight cylindrical coil spring 20 which is a material before forming the arc-shaped coil spring 30 according to the present invention. Various conditions are required in the cross sections at both ends of the arc-shaped coil spring 30 according to the above, and a condition for plastic deformation is required for the arc to be drawn at a position specified for the mounting angle in consideration of the arrangement of the contact surface 13. There is a thing, and it is necessary to satisfy the demand for stable operation by setting the angle for each specification.

  In addition, since both a straight cylindrical part and an arc shape are included during processing, the arc-shaped coil spring 30 and the straight cylindrical coil spring 20 which is a material before forming this are hereinafter referred to as “coil spring 10”. The end portion 11 is an end portion on the side of the coil spring 10 that is first deformed by the pressing member 91, and the opposite end portion 12 is an end portion on the opposite side of the end portion 11.

  FIG. 4 is an explanatory view of a fixing method of the straight cylindrical coil spring 20 or the arc-shaped coil spring 30 in the clamping process A according to the present invention, and FIG. 4 corresponds to the case where the straight cylindrical coil spring 20 has a different diameter. The clamp state in the case of the V-shaped clamp mechanism 50 that can be held is shown.

  The clamp mechanism 50 is a mechanism for fixing the straight cylindrical coil spring 20. As the fixing means, a clamp 51 having a claw portion 52 whose tip is bent in an L-shape is used. The clamp 51 has a claw portion 52 that is a part of the contact surface 13 of the seating surface on one side of the straight cylindrical coil spring 20. Insert and fix between the second and second effective number of turns.

  Specifically, for example, in order to prevent a twist or the like caused by the position of the contact surface 13, it is necessary to correct to an appropriate rotational position. Therefore, in the present invention, the state of being fixed by the clamp 51 is determined from the information obtained by each sensor 40 such as the photoelectric sensor 41, the image sensor 42, the contacted sensor 43, the proximity sensor 44, and the appropriate arrangement of the contact surface 13. A mechanism for rotating to a position is provided. That is, in FIG. 2 (b), the upper contact surface 13 is arranged in a balanced manner on the left and right, and in FIG. 2 (c), the lower contact surface 13 can be equally balanced on the left and right as well.

  In FIG. 4, the straight cylindrical coil spring 20 held by the clamp mechanism 50 is clamped, and the feed direction in the pitch feed process D with respect to the pressing member 91 is the side released from the pressing member 91, that is, from the clamping mechanism 50. A direction toward the pressing member driving mechanism 90 and the pitch feed direction L is indicated by arrows.

  As shown in FIGS. 4, 7, and 8, the clamp 51 is a rigid member having a claw portion 52 whose tip is bent in an L shape for fixing the straight cylindrical coil spring 20.

  The claw portion 52 is inserted into the inner diameter of the straight cylindrical coil spring 20 and has a substantially wedge shape for being sandwiched in the gap between the first and second effective wire diameters 14 from the contact surface 13 of the opposite end portion 12. It is a member to be formed.

  FIG. 5 is an operation explanatory view of the pressing member 91 in the pressing member driving step E according to the present invention, FIG. 5 (a) shows the pressing depth of the pressing member 91, and FIG. 5 (b) shows the servo. It is operation | movement explanatory drawing which shows the change of the speed V at the time of the pushing depth P of the press member 91 by the press 93, and this pushing. The technical main part, which is the greatest feature of the present invention, is to control the pushing operation of the pressing member 91 for each feed indicated by Feed in FIG. 5 (a). It is possible to change the depth and speed V between the coils, and it is possible to process not only the equal-length coil spring 10 but also the unequal-length coil spring 10 and the arc-shaped coil spring 30 having different curvatures. The point is that various angles can be performed with high accuracy, such as changing the pitch angle J between the pitches 15 for each region or gradually changing the pitches every 15 pitches.

  FIG. 6 shows the relationship between the contact surface 13 and the receiving surface in contact with the contact surface 13 in the arc-shaped coil spring manufacturing method 1 according to the present invention, and the curvature given to the arc-shaped coil spring 30 according to the present invention is free. Examples of such a change in curvature can be given.

  FIG. 6A shows an example in which the inclination with respect to the axial direction formed by the wire diameter per coil turn (hereinafter referred to as “pitch angle J”) is configured with the same pitch angle J throughout the arch shape. FIG. 6B shows an example in which a wide pitch angle J1 is arranged in the region near the center, and a narrow pitch angle J2 is arranged in the regions on both sides, and FIG. FIG. 6B shows an example in which a narrow pitch angle J2 is arranged in the region near the center, and a wide pitch angle J1 is arranged in the regions on both sides. Although it is possible to change the curvature angle by gradually increasing or decreasing the pitch-to-pitch angle J every 15 pitches, such an embodiment is difficult to show and is omitted because it is obvious as technical contents.

  6A to 6C show that the contact surface 13 is not necessarily perpendicular to the central axis of the arc-shaped coil spring 30. FIG. For example, in the case where a plurality of arc-shaped coil springs 30 are divided and arranged in the circumferential direction of the rotating shaft, the angle of the contact surface 13 in the assembled state and the state before being assembled is different, and the assembled state The desired curvature change can be freely realized by finely adjusting the push-down position P of the pressing member 91 in consideration of the correction value to the angle at which the repulsive force can be effectively received from the contact surfaces 13 at both ends. It becomes.

  FIG. 7 is an explanatory view for adjusting the mounting state of the pressing member 91 according to the present invention. 7A shows the inclination angle 92 of the pressing member 91, and FIG. 7B shows the coil spring 10 being processed.

  The pressing member 91 has a cutting edge 96 formed in a substantially wedge shape, and one side connecting two rectangular surfaces of the triangular prism is inserted into the pitch 15 from above, and each of the two rectangular surfaces is connected to the coil spring 10. It is a member for expanding the space 15 between the pitches by contacting and moving further downward and leaving plastic deformation with a desired curvature. The operation of the pressing member 91 is driven by controlling the servo press 93.

  The blade edge 96 has a sharp angle with one side connecting two sides of the triangular prism of the pressing member 91 as an apex, and is a portion that is pushed into the pitch 15.

  As shown in FIG. 7 (a), the inclination angle 92 will be described in the case where one side connecting the two faces of the triangular prism to the shape of the pressing member 91 is directed downward. The inclination of one side connecting the two faces of the rectangle. It is desirable that the angle 92 is an inclination angle 92 that is in a range from a position perpendicular to the axial direction of the coil spring 10 to ½ or less of the average inclination angle 92 of the wire diameter of one turn. However, the specification of the inclination angle 92 is intended to be disposed at both sides of the pressing member 91 and at an angle at which the force applied by the coil spring 10 to be deformed is equal, and the exact angle is designated. It is not a thing. By appropriately performing such an angle, it is possible to prevent twisting of the bending portion of the arc-shaped coil spring 30 that is bent.

  The pitch interval 15 is the distance in the axial direction of one turn among the effective number of turns continuous in the axial direction of the coil spring 10, and every time the pressing member 91 reciprocates in the vertical direction, the pitch feed mechanism This is the feed amount sent in the axial direction by 80.

  The servo press 93 has a pressurizing portion speed V (V1, V2, V3, -VR of the speed V with respect to the pushed-down position P shown in FIG. The servo motor is controlled by using a control means such as CNC (computerized numerical control), such as the number of times of pressure, to enable a complicated operation, and the pressing speed V and the pressing position when the pressing member 91 is processed. P (P0, PS, PA1, PA2, PUL), pressing force, etc. can be set numerically, and the servo press 93 moves to the middle of the press at high speed and reaches the lowest point of pressurization. It is possible to perform processing such as reducing the speed V in the vicinity or holding it at the pushed-down position P.

  The mold 94 is a mold 94 that is disposed below the coil spring 10 when the pressing member 91 spreads the coil spring 10, and the shape of the mold 94 is completed when the arc-shaped coil spring 30 is being processed. It is a member that does not interfere with the part and receives the force accompanying the pressing of the part being molded. Specifically, to the curvature of the arc-shaped coil spring 30, the deformation generated in the spring manufacturing process, such as the return amount of the elastic limit during processing of the arc-shaped coil spring 30 and the deformation amount in the quenching process, is added. The calculated curvature is required to be smaller in the mold 94 than at least the curvature of the arc-shaped coil spring 30.

  The guide plate 95 is a guide that guides the deformation of the coil spring 10 driven by the pressing member 91 in the pressing member driving mechanism 90, and causes the arc-shaped coil spring 30 to be distorted or twisted after being formed. In addition, it is possible to form a stable shape. In addition, it is effective that the guide plate 95 includes a guide groove or a protruding shape that is guided by contact with a curved surface corresponding to the curvature to be processed, from a simple one having flat plate-like members on both sides.

  FIG. 8 is an explanatory diagram showing a location where position information is detected by the sensor 40 according to the present invention. FIG. 8A shows a state in which the coil spring 10 is held by the clamp mechanism 50, and FIG. 8B shows a shape and surface state of the coil spring 10 viewed from the contact surface 13 side. It is explanatory drawing of the detection point S for detecting the feed amount of the horizontal direction of the coil spring 10, the up-and-down driving amount of the press member 91, etc. between A and the press member driving process E.

  The sensor 40 obtains, as an electronic signal, position information and shape information of an object to be detected for determining the operating speed and position of the pressing member 91 necessary for processing from the straight cylindrical coil spring 20 to the arc coil spring 30. It is a member. The sensor 40 is a member that detects whether or not the contact surface 13 is disposed at a specified position in the rotation angle positioning mechanism 70. For example, the image sensor 42 is used to detect the contact surface 13 and the contact surface 13 with the contact surface 13. A configuration in which the arrangement state of the contact surface 13 before and after the correction is confirmed based on the brightness of light with respect to other portions, or a configuration in which the inclination angle of the contact surface 13 is measured using a plurality of contact sensors may be used.

  The detection point S1 to the detection point S3 are places for detecting position information of the end 11 when the straight cylindrical coil spring 20 is clamped. In the drawing, the detection point S1 to the detection point S3 are shown from three locations, but the end 11 is a groove for placement in a clutch plate, a variable valve mechanism or the like that uses the arc coil spring 30 after being processed. Since there is a case where an angle is given to the axis of the coil spring 10 so as to be in contact with the surface of the coil spring 10, in this case, at least the flat contact surface 13 is set to about three. Detect at equal position. However, when it is perpendicular to the axial center, a straight line connecting one point on the inner side and one point on the outer side which are bent at least with respect to the flat contact surface 13 is detected.

  The detection point S4 to the detection point S7 detect the distance and position between the coils, and for the detection point S4 and the detection point S5, the center of the wire diameter of the maximum diameter with respect to the axial direction of the coil spring 10 is detected. For the detection point S6 and the detection point S7, the distance connecting the inside of the wire diameter with respect to the axial direction is detected, and the detection point S4 and the detection point S5, or the detection point S6 and the detection point S7, or a combination thereof is also controlled. Although it is possible, the processing accuracy can be improved by increasing the detection points S. The distance from the detection point S4 to the detection point S5 can be detected by the photoelectric sensor 41 and the proximity sensor 44, but the distance from the detection point S6 to the detection point S7 for detecting the same inter-coil distance is determined from the projector. Since the light to the light receiver may be blocked, the detection point S of the tension spring must be measured at the detection point S4 and the detection point S5. However, if the image sensor 42 is used, the detection point S4, the detection point S5, the detection point S6, and the detection point S7 are all bright and dark only by the reflection of light. If this is used, the light reaches the light receiver by the compression coil. Even if it is not, position information can be detected.

  The detection point S8 detects the vertical position of the pressing member 91, and in the relationship between the detection point S4 and the detection point S7, the vertical position information corresponding to the feed amount in the pitch feeding step D and the pressing member driving step E. Is detected. Since the tip of the pressing member 91 is provided with an inclination angle 92 as shown in FIG. 7A, the correction value input flow for correcting position information from the sensor 40 is shown in FIG. Although not described, it is of course necessary to appropriately add a necessary correction flow.

  Next, the pressing member 91 moves up and down about the detection point S8, and the positional information regarding the relationship with the pitch interval 15 of the coil spring 10 must be accurate. Therefore, it is necessary to use both the photoelectric sensor 41 and the image sensor 42 together and to select an appropriate sensor 40 to be used for each of the detection points S1 to S8.

  The detection surface T detects at what angle the planar portion of the end surface, which is the end portion 12 opposite to the end portion 11, is processed flat by cutting with respect to the axis of the coil spring 10. This is a part for detecting a correction amount for rotating to an appropriate position. The detection of the detection surface T by the sensor 40 is desirably performed by using the image sensor 42, and it is more effective to confirm it visually through a monitor.

  Note that the detection point S and the detection surface T are merely examples. For example, positional information between the pressing member 91 and the coil spring 10 can be input by other measurements, and the next operation command is appropriately determined from the current position by calculation or the like. What is necessary is just to be able to obtain the detection information which can be performed regardless of the type of the sensor 40.

  The photoelectric sensor 41 has the following types, which are appropriately selected and used depending on the state of the detection target. The transmission type is a detection method in which the detection object intercepts the optical axis between the opposing light projecting and light receiving devices, and the retro-reflection type is a detection method that detects the light coming out of the sensor 40 and returning from the reflector. The detection method detects by blocking, the diffuse reflection type is a detection method that irradiates the detection object with light and receives the reflected light from the detection object, and the narrow-field reflection type detects light on the detection object. This is a detection method in which the reflected light from the detection object is received and detected, and the limited reflection type has a light projecting part and a light receiving part having an angled structure so that each optical axis has a tolerance. The distance setting type is a detection method that detects the difference in the angle of the reflected light from the detected object by irradiating the spot to the detected object. The mold irradiates the object with a spot to reflect specular reflection and diffusion A method of detecting the difference.

  The image sensor 42 is a sensor 40 for processing the video captured by the camera to calculate the feature of the detected object from the area, the center of gravity, the length, the position, and the like, and outputting data and determination results. In such image processing, the length and size in the vertical and horizontal directions can be calculated from the background cut and the size of the image frame, and the reference position and the current position are corrected even when the position and orientation of the measurement object are not constant. It is possible. In addition, various corrections and control conditions can be obtained, such as adjustment of an offset amount when a positional deviation or the like occurs in advance can be easily performed using an application or the like.

  The proximity sensor 44 is a generic name of the sensor 40 for the purpose of detecting without contacting the detection target as an alternative to the contact detection method of the limit switch, and information such as movement information, presence information, or position information of the detected object. Is replaced with an electrical signal, and the detection result is used. The proximity sensor 44 has a method using a magnet or a reed switch, and is defined in the JIS standard based on the contact-type position detection switch. Among them, the sensor 40 is a type of sensor that is collectively referred to as a proximity switch that collectively detects the distance of an object and the presence or absence of a detection target in the vicinity of the object. For the metal, a dielectric type or a capacitance type magnetic detection type is used, the induction type can be a metal or non-ferrous metal, and the capacitance type can be a liquid or resin.

  The above-mentioned various sensors 40 are appropriately selected depending on various usage conditions depending on various conditions such as the distance to the detection object, the shape of the detection object, transparency, opacity, color discrimination, background influence, dust adhesion, etc. To do.

  Next, a control method based on input information from the sensor 40 will be described by showing each embodiment of the sensor 40.

  Any of the photoelectric sensor 41, the image sensor 42, and the proximity sensor 44 may be used as the sensor 40 used in the end detection process B for detecting the end 11 of the coil spring 10 fixed by the clamping process A. For example, When the photoelectric sensor 41 is used, the projector and the light receiver are arranged on both sides of the clamped coil spring 10 by the transmission type, and it is determined whether or not the end 11 of the coil spring 10 blocks the optical axis. It becomes possible to do.

  If the sensor 40 that detects the rotational position of the end portion 11 of the coil spring 10 in the rotation angle positioning process C is used in the case of using the photoelectric sensor 41, the light irradiation to the end face and the irradiation light from the end face are received. It is conceivable to detect using a diffuse reflection type using a light projector / receiver or a narrow field reflection type. Further, if the image sensor 42 is used, a method of detecting the ground surface of the end face and correcting the rotational position may be used.

  In the pitch feed process D, in order to detect the relationship between the tip position of the pressing member 91 and the driving position between the coils of the coil spring 10, position information and pitch feed amount for determining the feed amount sent by the feed device are obtained. To detect. In addition, as the sensor 40 used for the detection, either the photoelectric sensor 41 or the image sensor 42 may be used. However, depending on the distance or wire diameter between the coils of the coil spring 10, there is a gap between the coils. The photoelectric sensor 41 and the proximity sensor 44 may be malfunctioning. In such a case, it is effective to use the image sensor 42 to perform detection in consideration of brightness and darkness due to the unevenness of the coil.

  In the pressing member driving step E, the relationship between the tip position information of the pressing member 91 and the position information between the coils of the coil spring 10 is detected, and the vertical driving operation of the pressing member 91 corresponding to the pitch feed amount is controlled. Therefore, any one of the photoelectric sensor 41, the image sensor 42, and the proximity sensor 44 may be used for the detection. However, the distance between the coils of the coil spring 10 is narrow, and the photoelectric sensor 41 and the proximity sensor 44 malfunction. In such a case, it is effective to detect light and dark due to the unevenness of the coil by image processing using the image sensor 42. In particular, there is no problem when the gap between the coils is large as in the case of a compression spring, but the image sensor cannot be detected by the photoelectric sensor 41 or the like if the coils are in contact with each other in a normal state such as a tension spring. The use of 42 is effective.

  Position information input from each sensor 40 and information on changes in shape are collected in a PLC (programmable logic controller) such as a sequencer (registered trademark), and an operation command to a servo motor or a feeding device is output by calculation. Control various devices.

  FIG. 9 is a diagram illustrating the overall configuration of the arc-shaped coil spring manufacturing apparatus 2 according to the present invention. Such a manufacturing apparatus is an apparatus for carrying out the arc-shaped coil spring manufacturing method 1 and uses a clamp mechanism 50 that clamps and rotates the straight cylindrical coil spring 20 as a material, and a metal sensor or an image sensor 42. By an end detection mechanism 60, a rotation angle positioning mechanism 70 by providing a rotation mechanism in the clamp mechanism 50, a rotation angle control of a servo motor, a sensor 40 for optical detection such as a photodiode, and a slider control of the servo motor. A pitch feed mechanism 80 and a pressing member driving mechanism 90 using a servo press 93 are provided, and each mechanism is an apparatus that is executed by program control such as sequence control. It is also effective to use an air cylinder that uses compressed air instead of a servo motor. Hereinafter, characteristic mechanisms will be individually described.

  The clamp mechanism 50 has a structure for fixing the straight cylindrical coil spring 20 in order to process it. As shown in FIGS. 4, 7B and 8A, the fixing means has an L-shaped tip. A clamp 51 having a pawl portion 52 bent in a shape is used, and the clamp 51 has the first and second effective winding numbers of the contact surface 13 of the seating surface on one side of the straight cylindrical coil spring 20. Fix it in between.

  The end detection mechanism 60 is a device for detecting the position information of the end 11 in a state where the straight cylindrical coil spring 20 is held by the clamp mechanism 50 using the sensor 40. Specifically, for example, the photoelectric sensor 41 is used for the sensor 40, and the straight cylindrical coil spring 20 is formed by a light projector for irradiating light and a light receiver for receiving light provided on both sides of the end portion 11 of the straight cylindrical coil spring 20. Along with the operation of the pitch feed mechanism 80, the light receiving light received by the light receiver is detected, and this position is obtained as position information with the end 11 as the position. Note that it is also effective to employ a configuration in which a plurality of the sensors 40 used in the end detection mechanism 60 are provided or a configuration in which the angle is detected by the image sensor 42 so that the angle of the detection surface T of the end 11 can be measured.

  The rotation angle positioning mechanism 70 rotates to a specified position when it is specified that the rotation angle of the contact surface 13 is specified in a state in which the straight cylindrical coil spring 20 is held by the clamp mechanism 50. This is a device that corrects the image, and the sensor 40 confirms the mounting state and controls the operation for correction.

  The pitch feed mechanism 80 is a device that moves the pressing member 91 to a position where the pressing member 91 is pressed down between the pitches 15 of the coil spring 10. The pitch feeding mechanism 80 moves the tip of the pressing member 91 so that one side of the pressing member 91 is at an appropriate position. is there. For the amount of movement of the pitch feed mechanism 80, input of a designated numerical value and the optical detection mechanism may be used. As a simple one, if the amount of movement is always constant like the isometric coil spring 10, a repeated operation can be easily commanded, and the operation command control program can be very simple. . Furthermore, even when it is desired to change the curvature slightly or to form a complex arc-shaped coil spring 30 with different partial curvatures, programming is performed to set in detail the amount of push-in and speed V corresponding to the shape. It is also possible to process into such a shape by performing.

  The pressing member driving mechanism 90 is a device that moves the pressing member 91 up and down using a servo press 93. The pressing amount, the pressing position P, and the speed V can be set in detail by the control program. That is, in the conventional cam-type driving method which is the prior art, it is difficult to freely set the amount of depression and the curvature even if the change in the speed V can be controlled. It is possible to make a slight change in the amount of push-in by the detailed setting by, and the adjustment of the holding time etc. in the holding state can be controlled, and in the plastic deformation that leaves the permanent strain exceeding the elastic limit, Since various effects can be easily calculated in the spring design, it is possible to manufacture the coil spring 10 having a complicated shape such as unequal linearity or unequal pitch.

  The present invention is a combination of a first technical element that employs a conventional clamping mechanism 50 and a second technical element that performs control based on a more accurate mounting position using various sensors 40. As a result, the machining time can be significantly reduced as compared with the conventional apparatus, and it is clear that the productivity can be dramatically improved.

  INDUSTRIAL APPLICABILITY The present invention can provide a highly accurate spring at a low cost in the manufacturing industry for manufacturing an arc spring having a curvature such as an automobile clutch, and is considered to have high industrial applicability.

DESCRIPTION OF SYMBOLS 1 Arc-shaped coil spring manufacturing method 2 Arc-shaped coil spring manufacturing apparatus 10 Coil spring 11 End 12 Opposite end 13 Abutting surface 14 Effective wire diameter 15 Pitch 20 Straight cylindrical coil spring 30 Arc-shaped coil spring 40 Sensor 41 Photoelectric sensor 42 Image sensor 43 Contacted sensor 44 Proximity sensor 50 Clamp mechanism 51 Clamp 52 Claw part 60 End detection mechanism 70 Rotation angle positioning mechanism 80 Pitch feed mechanism 90 Press member driving mechanism 91 Press member 92 Inclination angle 93 Servo press 94 Die 95 Guide plate 96 Cutting edge A Clamping process B Edge detection process C Rotational angle positioning process D Pitch feed process E Pressing member driving process J Pitch angle L Pitch feed direction P Depressed position (P0, PS, PA1, PA2, PUL)
S detection point (S1, S2, S3, S4, S5, S6, S7, S8)
T Detection surface V speed (V1, V2, V3, -VR)

Claims (4)

A method of manufacturing a coil spring (10) having a curvature from a straight cylinder,
A clamping step (A) for fixing the straight cylindrical coil spring (20);
An end detection step (B) for detecting the end (11);
Rotation angle positioning step (C);
Pitch feed process (D);
A pressing member driving step (E);
Consisting of
In the clamping step (A), a clamp (51) having a claw portion (52) bent at the tip in an L shape downward is used, and the claw portion (52) is provided on one side of the straight cylindrical coil spring (20). Sandwiched between the effective wire diameters (14), which are the first and second effective windings from the seating surface, and fixed,
The end detection step (B) detects the position of the end portion (11) of the straight cylindrical coil spring (20) in order to obtain position information as an operation reference of the pitch feed step (D),
In the rotation angle positioning step (C), the contact surface (13) of the end (11) to which the straight cylindrical coil spring (20) is fixed is rotated and adjusted,
The pitch feed process (D) moves the straight cylindrical coil spring (20) to an appropriate position during the position where the pressing member driving process (E) starts and the pressing member driving process (E),
In the pressing member driving step (E), the operation of driving the pressing member (91) from above into the pitch interval (15) and pulling it back upward is controlled between the adjacent pitches (15) by controlling the servo press (93). )
Each operation in the pitch feeding step (D) and the pressing member driving step (E) is to form an arc-shaped coil spring (30) having an arbitrary curvature by performing speed (V) control and position control. An arc-shaped coil spring manufacturing method (1). Each operation required in each step of the pressing member driving step (E) from the end detection step (B),
It is controlled based on position and shape information obtained from each sensor (40) of any one of photoelectric sensor (41), image sensor (42), contacted sensor (43), proximity sensor (44), or a combination thereof. The method (1) for producing an arc coil spring according to claim 1, wherein the method is employed. A manufacturing apparatus for manufacturing a coil spring (10) having a curvature from a straight cylinder,
A clamp mechanism (50) for fixing the straight cylindrical coil spring (20);
An end detection mechanism (60) for detecting the end (11), a rotation angle positioning mechanism (70),
A pitch feed mechanism (80);
A pressing member driving mechanism (90);
Consisting of
The clamp mechanism (50) uses a clamp (51) having a claw portion (52) whose tip is bent downward in an L shape, and the claw portion (52) is provided on one side of the straight cylindrical coil spring (20). Between the effective wire diameter (14), which is the first and second effective number of turns from the seating surface, and fixed,
The end detection mechanism (60) detects position information of the end (11) of the straight cylindrical coil spring (20) in order to obtain position information serving as an operation reference of the pitch feed mechanism (80),
The rotation angle positioning mechanism (70) adjusts the contact surface (13) to a predetermined position by rotating the straight cylindrical coil spring (20) fixed by the clamp mechanism (50),
The pitch feed mechanism (80) moves the straight cylindrical coil spring (20) to an appropriate position at the position where the operation of the pressing member driving mechanism (90) starts and during the operation,
The pressing member driving mechanism (90) repeatedly performs the operation of driving the pressing member (91) from above into the pitch (15) and pulling it back upward, from the straight tube shape to the arc-shaped coil spring (30) having a curvature. Servo press (93) is used for the operation to deform
A shape having an arbitrary curvature is formed by controlling the operations of the pitch feed mechanism (80) and the pressing member driving mechanism (90) to an appropriate speed (V) and position, respectively. Arc coil spring manufacturing device (2). Necessary operations in the end detection mechanism (60), the rotation angle positioning mechanism (70), the pitch feed mechanism (80), and the pressing member driving mechanism (90) are as follows.
It is controlled based on position and shape information obtained from each sensor (40) of any one of photoelectric sensor (41), image sensor (42), contacted sensor (43), proximity sensor (44), or a combination thereof. An arc coil spring manufacturing apparatus (2) according to claim 3, characterized in that: