JP2006346729A - Wire-rod feeding device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wire-rod feeding device capable of preventing servo down caused by generation of heat, by suppressing vibration of a servo motor. <P>SOLUTION: Each of output rotary shafts 45S of servo motors 45 in a plurality of feeding mechanism parts 20A is connected to each other with a timing belt 55 without using gears. Thereby, when some of a plurality of servo motors 45 are driven and controlled in a state that a load is applied only to them, and the remaining servo motors 45 are driven and controlled in a state that the load is not applied to them, the servo motors 45 that receive the load and are made suppressed not to vibrate regulate the generation of vibration of the servo motors 45 in the state of non-load, so that the servo down caused by generation of heat is prevented. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a wire feeding device that feeds a wire by sandwiching the wire between a plurality of rollers and rotationally driving the rollers with a servo motor.

The conventional wire feeding device shown in FIG. 8 includes a plurality (specifically, two) of feeding mechanisms 3. Each feeding mechanism section 3 is provided with a pair of rollers 2 and 2 arranged one above the other with the wire 1 in between, and the rotational position of the rollers 2 and 2 is controlled by the servo motor 4 shown in FIG. A wire rod was fed (see, for example, Patent Document 1).
JP 2003-230926 A (paragraph [0036], FIGS. 1 and 2)

  By the way, as described above, the wire rod feeding device provided with a plurality of feeding mechanism units 3 includes a single servo motor 4 as a common drive source among the plurality of feeding mechanism units 3, Some of the feeding mechanisms 3 are each provided with a servo motor 4. As described above, in the wire rod feeding device provided with the servo motors 4 in each of the plurality of feeding mechanism sections 3, since each servo motor 4 is downsized and the rotor inertia is reduced, the response to the operation command is improved. The feeding / stopping of each wire 1 can be quickly switched.

  However, a situation may occur in which only a part of the feeding mechanism units 3 is active so as to apply an axial force to the wire 1 and the remaining feeding mechanism units 3 are driven by receiving a force from the wire 1. In the feeding mechanism unit 3 in the active state, the servo motor 4 is driven and controlled while receiving a load (feeding resistance), while in the feeding mechanism unit 3 in the driven state, the servo motor 4 is not provided. Drive control is performed in a load state, and the damper function on control is lowered. For this reason, in the feeding mechanism unit 3 in the driven state, an oscillation phenomenon in which the servo motor 4 slightly moves within the backlash range of the gear 5 (see FIG. 9) provided between the servo motor 4 and the roller 2 may occur. As described above, since the servo motor 4 has good responsiveness, the oscillation frequency is increased, and the servo is down due to heat generation.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a wire rod feeding device capable of suppressing servo motor oscillation and preventing servo down due to heat generation.

  In order to achieve the above object, a wire feeding device according to the invention of claim 1 includes a pair of rollers that rotate symmetrically with a wire interposed therebetween, and a servo motor coupled to the rollers via a gear. In a wire rod feeder that feeds a wire rod by controlling the rotational position of a roller by each servo motor of the plurality of feed mechanism portions, and having a plurality of feed mechanism portions It is characterized in that the output rotation shafts of the servo motors are connected by a timing belt without using a gear.

  According to a second aspect of the present invention, in the wire rod feeding device according to the first aspect, at least three feeding mechanism portions are provided, and the output rotation shaft of the servo motor is a timing belt between all the feeding mechanism portions. It is characterized by being connected.

  According to a third aspect of the present invention, in the wire rod feeding device according to the second aspect, at least three feeding mechanism portions are provided, and servo motors provided in the feeding mechanism portions are arranged along the feeding direction of the wire rod. The output servo shafts of adjacent servo motors are connected by a timing belt.

  According to a fourth aspect of the present invention, in the wire rod feeding device according to any one of the first to third aspects, at least three feeding mechanism portions are provided, and the wire rod clamping force by a pair of rollers is used to feed the wire rod. It is characterized by the fact that it gradually becomes larger toward the front of the direction.

  According to a fifth aspect of the present invention, in the wire rod feeding device according to any one of the first to fourth aspects, a speed reducer is provided between the roller and the servo motor, and the timing belt is locked to the input rotation shaft of the speed reducer. It has the feature in the place which supported the pulley for this.

  The invention of claim 6 is characterized in that, in the wire rod feeding apparatus according to any one of claims 1 to 5, the servo motor is an ultra-low inertia motor.

  According to the configuration of the first aspect, since the output rotation shafts of the servo motors are connected to each other by the timing belt without using a gear between the plurality of feeding mechanism units, some of the servo motors among the plurality of servo motors. Even if only the servomotor is driven and controlled under load, and the remaining servomotors are driven and controlled without load, the servomotor that receives oscillation and is suppressed from oscillation is in the noload state. It is possible to regulate the oscillation of the servo motor and prevent servo down due to heat generation

  Here, as a configuration in which the output rotation shafts of the servo motors are connected by a timing belt between the plurality of feeding mechanism units, the plurality of feeding mechanism units are divided into two or more groups, and the feeding mechanism of each group The output rotation shafts of the servo motors may be connected to each other by a timing belt, and the servo between all the feeding mechanisms provided in the wire feeding device as in the invention of claim 2. You may make it the structure which connected the output rotating shaft of the motor with the timing belt. According to the second aspect of the present invention, when some servo motors are in a no-load state, the oscillations of the servo motors can be restricted by all the remaining servo motors, and the oscillations can be reliably suppressed. it can.

  In addition, as a configuration in which the output rotation shaft of the servo motor is connected by a timing belt among all the feeding mechanism units, all the other feeding mechanism units are connected to the output rotating shaft of the servo motor of one feeding mechanism unit. The output rotation shafts of the servo motors may be connected to each other, and the servo motors of all the feeding mechanisms are arranged along the wire feeding direction as in the invention of claim 3 and adjacent servos. You may make it the structure which connected the output rotating shafts of the motor with the timing belt. And according to the structure of Claim 3, each timing belt can be made comparatively short, and installation of a timing belt becomes easy.

  Further, when at least three feeding mechanism portions are provided, the wire pinching force by the rollers of each feeding mechanism portion is directed forward in the wire feeding direction as in the configuration of claim 4. It becomes possible to feed the wire smoothly by gradually increasing it according to the above.

  Further, when a speed reducer is provided between the roller and the servo motor, if the pulley for locking the timing belt is supported on the input rotation shaft of the speed reducer as in the configuration of claim 5, the pulley shaft There is no need to separately provide supporting shaft parts, and the number of parts can be reduced.

  Furthermore, as in the configuration of the sixth aspect, by making the servo motor an ultra-low inertia motor, agile switching of the wire feeding operation is possible.

[First Embodiment]
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment according to the invention will be described with reference to FIGS.
The spring molding machine 10 shown in FIG. 1 includes a substrate 30 that is vertically erected and assembled with a forming tool 14T, 15T, a cutting tool 13T, a mandrel tool 12, and the like in addition to the wire rod feeding device 20S according to the present invention. Yes. The mandrel tool 12 protrudes from the front surface of the substrate 30, one forming tool 15T is disposed obliquely below the mandrel tool 12, the other forming tool 14T is disposed obliquely above the mandrel tool 12, A cutting tool 13T is disposed above the mandrel tool 12. The cutting tool 13T and the forming tools 14T, 15T move linearly with the servo motors 13M, 14M, 15M as drive sources, respectively, and move forward and backward with respect to the forming space R in the vicinity of the mandrel tool 12. Then, when the wire rod feeding device 20S feeds the wire rod 90 into the forming space R, as shown in FIG. 2, the wire rod 90 is slidably contacted with the tip surfaces of the respective forming tools 14T and 15T, and is plastically deformed into an arc shape. A coil spring is formed so as to surround the gold tool 12. When the spring length of the coil spring reaches a predetermined length, the cutting tool 13T advances to the forming space R side, and a part of the wire 90 is cut between the edge of the cutting tool 13T and the edge of the mandrel tool 12. Then, the coil spring having a predetermined length is separated from the subsequent wire 90. In addition, wire rod sliding contact grooves 14Z and 15Z for guiding the wire rod 90 are formed on the tip surfaces of the forming tools 14T and 15T.

  As shown in FIG. 1, the wire feeding device 20S includes four feeding mechanisms 20A arranged in the horizontal direction. Each feeding mechanism section 20A has a pair of rollers 21 and 21 arranged vertically. In order to support the rollers 21 and 21, as shown in FIG. 3, a pair of output stage shafts 25A and 25B are rotatably assembled to the base plate 30 and the base 31 behind it (left side in FIG. 3). It has been. These output stage shafts 25A and 25B are arranged vertically in parallel and rollers 21 and 21 are fitted to one end of each of the output stage shafts 25A and 25B. Each roller 21 is pinned to a flange portion 25F formed integrally with the output stage shafts 25A and 25B (the pin is not shown) and screwed to one end face of each output stage shaft 25A and 25B. It is retained by the board 22. In addition, gears 26 and 26 are provided on the other end sides of the output stage shafts 25A and 25B, respectively, and the upper and lower rollers 21 and 21 rotate in contrast to each other when the gears 26 and 26 are engaged with each other.

  As shown in FIG. 4, a pair of grooves 21 </ b> M and 21 </ b> N extend in the circumferential direction on the outer peripheral surface of the roller 21. The inner surfaces of both the grooves 21M and 21N have arc shapes with different curvatures, and the large grooves 21N and 21N and the small grooves 21M and 21M face each other between the rollers 21 and 21. Further, the arrangement of the large and small grooves 21M and 21N can be reversed by attaching the rollers 21 and 21 to the output stage shafts 25A and 25B with the reverse sides of the rollers 21 and 21 with respect to the state of FIG. The wire 90 is passed between the grooves 21N and 21N facing each other at the position close to the substrate 30, and is sandwiched between the rollers 21 and 21. In this state, the rollers 21 and 21 are slightly separated from each other, so that the holding force of the rollers 21 and 21 is applied to the wire 90.

  As shown in FIG. 1, the wire rod 90 is sandwiched between rollers 21 and 21 in all the feeding mechanism portions 20A so as to cross the entire four feeding mechanism portions 20A. Thereby, the wire 90 extends in the horizontal direction, and the tip thereof faces the molding space R. Further, in the feeding direction of the wire rod 90, a nozzle 70 is provided along the feed line of the wire rod 90 between the front and rear of the feeding mechanism portion 20A group and between the adjacent feeding mechanism portions 20A, 20A. The wire 90 is guided through the inside of the nozzle 70.

  As shown in FIG. 3, a block accommodation hole 30 </ b> A extending in the vertical direction is formed in a portion of the substrate 30 through which the output stage shafts 25 </ b> A and 25 </ b> B penetrate. A pair of blocks 24, 24 are accommodated in a vertically overlapping manner at the lower end side of the block accommodation hole 30A. The lower block 24 is fixed to the substrate 30, and the upper block 24 is movable up and down. One end portions of the output stage shafts 25A and 25B are rotatably supported by these blocks 24 and 24. An air cylinder 23 is fixed to the upper end portion of the block accommodation hole 30 </ b> A, and a linear motion rod 23 </ b> R extending downward from the air cylinder 23 is connected to the upper block 24. The bearing 25R that pivotally supports the end of the upper output stage shaft 25A away from the roller 21 has a structure that allows the output stage shaft 25A to swing. And the clamping force of the wire 90 by the rollers 21 and 21 can be changed by adjusting the air supply pressure to the air cylinder 23. Further, in the present embodiment, the clamping force of the rollers 21 and 21 in the feeding mechanism portion 20A is set so as to gradually increase toward the front in the feeding direction of the wire 90 (on the molding space R side).

  A pair of input stage shafts 28A and 28B are arranged vertically below the lower output stage shaft 25B, and both ends thereof are rotatably supported by the base 31. Among them, the movable pair gear 41 is assembled to the upper input stage shaft 28A so as to be integrally rotatable and slidable, and the fixed pair gear 40 is assembled to the lower input stage shaft 28B so as to be integrally rotatable and non-slidable.

  The fixed pair gear 40 is integrally provided with a small gear 40A and an intermediate gear 40B. On the other hand, the movable pair gear 41 is formed by integrating a large gear 41A and an intermediate gear 41B. The large gear 41A of the movable pair gear 41 is disposed on the side corresponding to the small gear 40A of the fixed pair gear 40, and the middle gear 41B of the movable pair gear 41 is disposed on the side corresponding to the middle gear 40B of the fixed pair gear 40. Further, between the large gear 41A and the middle gear 41B, a relay portion 41C having an outer diameter smaller than the root diameter of the middle gear 41B is provided. When the movable pair gear 41 is arranged at one end of the slidable stroke, the large gear 41A of the movable pair gear 41 and the small gear 40A of the fixed pair gear 40 are engaged with each other as shown in FIG. The middle gear 40B faces the relay portion 41C, and the middle gears 40B and 41B idle. On the other hand, when the movable pair gear 41 is arranged on the other end side of the stroke, the middle gear 41B of the movable pair gear 41 and the middle gear 40B of the fixed pair gear 40 are engaged with each other, and the small gear 40A of the fixed pair gear 40 is connected to the relay portion 41C. The large and small gears 40A and 41A are idled facing each other. Thus, the gear ratio can be changed between the upper and lower input stage shafts 28A and 28B.

  In addition, a lever locking groove 41D is formed in the relay portion 41C of the movable pair gear 41 in the circumferential direction, and a lever 29 for manually sliding the movable pair gear 41 is locked therein. Further, a pair of limit switches 42A and 42B are provided in the swing region of the lever 29. Based on the detection signals output from the limit switches 42A and 42B, it is determined whether the movable pair gear 41 is disposed on one end side or the other end side of the slidable stroke.

  An output gear 27 is assembled to an end of the upper input stage shaft 28A opposite to the movable pair gear 41 so as to be integrally rotatable, and the gear 26 of the lower output stage shaft 25B is meshed with the output gear 27. ing. Accordingly, the upper and lower input stage shafts 28A and 28B and the upper and lower output stage shafts 25A and 25B rotate in conjunction with each other.

  A servo motor 45 is connected to the lower input stage shaft 28B via a speed reducer 44. Specifically, the position near the rear end of the input stage shaft 28B (position near the end on the side away from the substrate 30) is pivotally supported via a bearing on an upright wall 31A provided on the base 31, and the input stage shaft The rear end portion of 28B protrudes rearward from the upright wall 31A. The outer case 44H of the speed reducer 44 is fixed to an upright wall 31B opposed from the rear of the upright wall 31A, and the output rotary shaft 44S of the speed reducer 44 and the lower input stage shaft between the upright walls 31A and 31B. The rear end of 28 </ b> B is connected by a shaft coupling 43.

  A cylindrical sleeve 51 is fixed to the rear end portion of the outer case 44H in the speed reducer 44. As shown in FIG. 5, inside the cylindrical sleeve 51, an input rotary shaft 52 of the speed reducer 44 is rotatably supported by bearings 52B1 and 52B2. Specifically, the input rotation shaft 52 includes a gear portion 52G, a pulley support portion 52P, and a motor coupling portion 52C in order from the speed reducer 44 side. The outer diameter of the pulley support portion 52P is slightly larger than that of the gear portion 52G, and the outer diameter of the motor connection portion 52C is approximately twice the outer diameter of the pulley support portion 52P. The end of the motor connecting portion 52C on the pulley support portion 52P side is pivotally supported by one bearing 52B1, and the end of the pulley support portion 52P on the gear portion 52G side is pivotally supported by the other bearing 52B2. .

  The gear portion 52G enters into the outer case 44H and meshes with a gear (not shown) that constitutes the speed reducer 44. A cylindrical hole (not shown) is formed in the central portion of the motor connecting portion 52C, and the output rotation shaft 45S of the servo motor 45 is inserted therein and key-coupled. A stator 45H of the servo motor 45 is fixed to the rear end portion of the cylindrical sleeve 51. Thus, when the output rotation shaft 45S of the servo motor 45 is rotationally driven, the output torque of the servo motor 45 is transmitted to the output stage shafts 25A and 25B via the speed reducer 44, the fixed pair gear 40, the movable pair gear 41, and the like. The rollers 21 and 21 rotate symmetrically.

  The servo motor 45 is a so-called ultra-low inertia motor, and is longer in the axial direction than a normal cylindrical motor, thereby suppressing the rotor inertia.

  Among the four feeding mechanism parts 20A, the pulley support part 52P provided in the central two feeding mechanism parts 20A, 20A (the two left feeding mechanism parts 20A, 20A in FIG. 5) includes a pair of pulleys 53, 54 is fitted. One of the pulleys 53 is screwed to the end surface of the motor connecting portion 52 </ b> C, and the other pulley 54 is screwed to the end surface of the pulley 53. Further, the cylindrical sleeve 51 provided in the two central feeding mechanisms 20A includes a part of a portion facing the outer peripheral surface of one pulley 53 and a part of a portion facing the outer peripheral surface of the other pulley 54. Are respectively cut out to form belt insertion holes 51W1 and 51W2. These belt insertion holes 51W1 and 51W2 are open in opposite directions, and between the two central feeding mechanisms 20A and 20A, one belt insertion hole 51W2 and 51W2 located on the speed reducer 44 side is located between the belt insertion holes 51W1 and 51W2. The other belt insertion holes 51 </ b> W <b> 1 and 51 </ b> W <b> 1 that face each other and are located on the servo motor 45 side face each other. A timing belt 55 is passed between the pulleys 54 and 54 facing each other through the belt insertion holes 51W2 and 51W2 between the feeding mechanisms 20A and 20A.

  Of the four feeding mechanism parts 20A, two feeding mechanism parts 20A at both ends (in FIG. 5, only the feeding mechanism part 20A on the side close to the molding space R of the two feeding mechanism parts 20A at both ends is shown in FIG. (Shown on the right) does not have one pulley 54 and belt insertion hole 51W2 in the two central feeding mechanism portions 20A described above, and has only the other pulley 53 and belt insertion hole 51W1. ing. The rest of the configuration is the same as that of the two central feeding mechanisms 20A. The belt insertion holes 51W1 and 51W1 on the servo motor 45 side face each other between the two feeding mechanism portions 20A at both ends and the two feeding mechanism portions 20A at the center. Then, the timing belt 55 is passed between the pulleys 53 and 53 facing each other through the belt insertion holes 51W1 and 51W1 between the two feeding mechanism portions 20A at both ends and the two feeding mechanism portions 20A at the center. ing.

  With these configurations, as shown in FIG. 6, the output rotation shafts 45S of the adjacent servo motors 45 are connected to each other by the timing belt 55, and the output rotation shafts of all the servo motors 45 provided in the wire rod feeding device 20S. 45S is connected.

  A pulley 60 is provided between the adjacent cylindrical sleeves 51, 51, and these pulleys 60 are pressed against the inner surface of the timing belt 55. As shown in FIG. 5, the pulley 60 is assembled to a rib 31C protruding from the upright wall 31B of the base 31, and can be moved up and down by an adjustment mechanism (not shown). Thereby, the tension of the timing belt 55 can be adjusted.

  The wire feeding device 20 </ b> S is driven and controlled by a control device (not shown) provided in the spring molding machine 10. Specifically, the control device stores rotational position data relating to the output rotational shaft 45S of the servo motor 45 as a substitute value for the rotational position of the roller 21. Further, the control device takes in the detection signal of the position sensor 45E provided in each servo motor 45 and the detection signals of the limit switches 42A and 42B. Based on the detection signals of the limit switches 42A and 42B, the control device specifies the reduction ratio (gear ratio) between the servo motor 45 and the roller 21, and based on the reduction ratio and the rotational position data of the output rotary shaft 45S. Then, a command value for the rotational position of the output rotary shaft 45S for each predetermined period is generated. Then, a motor drive current corresponding to the deviation between the actual rotation position of the output rotation shaft 45S detected by the position sensor 45E and the command value is supplied to the servo motor 45. In this way, the control device performs feedback control on the rotational position of the roller 21.

Next, the operation of the present embodiment configured as described above will be described.
When the spring molding machine 10 is activated, the control device drives and controls all the servo motors 45 provided in the wire rod feeding device 20S to feed the wire rod 90 intermittently toward the forming space R by a predetermined amount. Then, a predetermined amount of the wire 90 fed is slidably contacted with the forming tools 14T and 15T in the forming space R and formed into a coil spring. When the coil spring reaches a predetermined spring length, the coil spring is cut off from the subsequent wire 90 by the mandrel tool 12 and the cutting tool 13T. Thereby, a coil spring is manufactured sequentially. Here, in the wire rod feeding device 20S of the present embodiment, since the servo motor 45 provided in each feeding mechanism portion 20A is an ultra-low inertia motor, the response to the command from the control device is improved, and the wire rod 90 It becomes possible to quickly switch between feeding and stopping. In other words, the spring molding machine 10 can be operated at high speed.

  Further, in the wire rod feeding device 20S of the present embodiment, since the pinching force of the wire rod 90 by the feeding mechanism portion 20A is gradually increased toward the molding space R, the pinching force of all the feeding mechanism portions 20A is uniform. The wire rod 90 can be fed smoothly as compared with the case of the above.

  By the way, when the wire rod feeding device 20S feeds the wire rod 90, sliding resistance between the wire rod 90 and the forming tools 14T and 15T is applied as a load to the servo motor 45 of the wire rod feeder 20S. In the configuration in which the servo motor 45 is provided in each of the plurality of feeding mechanism units 20A, such as the wire feeding device 20S of the present embodiment, a part of the feeding mechanism units 20A (for example, two feeding mechanisms at both ends). There may be a situation in which only the servo motor 45 of the feeding mechanism unit 20A) is loaded, and the servo motors 45 of the remaining feeding mechanism units 20A (two feeding mechanism units 20A in the center) become unloaded. Specifically, in some of the feeding mechanism units 20A, the output torque of the servo motor 45 is transmitted to the roller 21 via the speed reducer 44, the fixed pair gear 40, and the like, and the reaction force is applied to the servo motor 45 as a load. On the other hand, in the remaining feeding mechanism portion 20A, the roller 21 and the speed reducer 44 may be operated by the force received through the wire 90, and the servo motor 45 may be driven and controlled without load.

  However, in the wire rod feeding device 20S of the present embodiment, the output rotation shafts 45S of the servo motors 45 are connected by the timing belt 55 between the plurality of feeding mechanism portions 20A without using a gear. The servo motor 45 in which the oscillation is suppressed can restrict the oscillation of the servo motor 45 in the no-load state and can prevent the servo down due to heat generation. In addition, since the output rotation shafts 45S of the servomotors 45 are connected to each other by the timing belt 55 between all of the feeding mechanisms 20A, when some of the servomotors 45 become unloaded, the servomotors 45 Can be regulated by all the remaining servo motors 45, and the oscillation can be reliably suppressed. Further, since the pulleys 53 and 54 for locking the timing belt 55 are pivotally supported on the input rotary shaft 52 of the speed reducer 44, it is not necessary to separately provide a shaft part for pulley pivotal support, thereby reducing the number of parts. It is done.

[Second Embodiment]
The wire rod feeding device 20T of the present embodiment is shown in FIG. The wire rod feeding device 20T includes two feeding mechanism portions 20A, and these feeding mechanism portions 20A are the central two feeding mechanism portions 20A among the four feeding mechanism portions 20A of the first embodiment. It has the same configuration as And the timing belt 55 is passed between the pulleys 54 and 54 with which both these feed mechanism parts 20A were equipped, and the servomotor 45 of both feed mechanism parts 20A becomes a structure which mutually controls an oscillation.

  Each feeding mechanism 20A is provided with an auxiliary servo motor 45V in addition to the servo motor 45 described above. These auxiliary servo motors 45V are disposed at the same positions as the servo motors 45 in the feeding mechanism portions 20A and 20A at both ends of the first embodiment. The pulley 53 is key-coupled to the output rotating shaft 45W of the auxiliary servo motor 45V, and the timing belt 55 is passed between the pulleys 53, 53 provided in the servo motor 45 and the auxiliary servo motor 45V. ing. As a result, the servo motor 45 can be assisted by the auxiliary servo motor 45V to increase the axial force that can be applied to the wire 90 from the feeding mechanism portion 20A.

  Further, since all of the servo motor 45 and the auxiliary servo motor 45V are connected to each other by the timing belt 55, when some servo motors 45 and / or the auxiliary servo motor 45V are in a no-load state, these servo motors 45 and / or the oscillation of the auxiliary servo motor 45V can be regulated by the remaining servo motor 45 and / or the auxiliary servo motor 45V, and the oscillation can be reliably suppressed.

[Other Embodiments]
The present invention is not limited to the above-described embodiment. For example, the embodiments described below are also included in the technical scope of the present invention, and various other than the following can be made without departing from the scope of the invention. It can be changed and implemented.

  (1) The number of the feeding mechanism units included in the wire feeding device according to the present invention is not limited to two or four illustrated in the first and second embodiments, and is 3 if there are a plurality of feeding mechanisms. It may be one or five or more.

  (2) Instead of the lever 29 of the first embodiment, a linear drive source (for example, an air cylinder) for sliding the movable pair gear 41 may be provided.

  (3) In the first embodiment, the reduction ratio (gear ratio) between the servo motor 45 and the roller 21 can be changed. However, the reduction ratio between the servo motor and the roller is fixed. Also good.

  (4) Although the wire rod 90 fed by the wire rod feeding device 20S of the above embodiment has a circular cross section, the wire rod may have a rectangular cross section.

  (5) In the above-described embodiment, the speed reducer 44 is provided between the servo motor 45 and the input stage shaft 28B. However, the output rotary shaft 45S of the servo motor 45 is connected to the input stage shaft 28B without providing the speed reducer 44. You may make it the structure connected with.

The front view of the spring molding machine which concerns on 1st Embodiment of this invention. A perspective view of a coil spring formed by sliding a wire rod against a forming tool Cross-sectional side view of wire feeder Roller side sectional view Cross section of wire feeder Front sectional view of wire feeder Front sectional view of the wire feeding device of the second embodiment Front view of conventional wire feeder Cross-sectional side view of a conventional wire feeder

Explanation of symbols

20A Each feeding mechanism unit 20S, 20T Wire rod feeding device 21 Roller 44 Reducer 45 Servo motor 45S Output rotation shaft 52 Input rotation shaft 53, 54 Pulley 55 Timing belt 90 Wire rod

Claims (6)

A plurality of feeding mechanism units each including a pair of rollers that rotate symmetrically with a wire interposed therebetween, and a servo motor coupled to the rollers via a gear; In the wire rod feeding device that feeds the wire rod by controlling the rotational position of the roller by each servo motor,
A wire rod feeding device characterized in that the output rotation shafts of the servo motors are connected to each other by a timing belt between the plurality of feeding mechanism portions without passing through the gear.   2. The wire feeding according to claim 1, wherein at least three feeding mechanism portions are provided, and an output rotation shaft of the servo motor is connected by the timing belt between all of the feeding mechanism portions. apparatus.   At least three or more of the feeding mechanism sections are arranged, the servo motors provided in the feeding mechanism sections are arranged along the feeding direction of the wire rod, and the output rotation shafts of the adjacent servo motors are aligned with the timing belt. The wire rod feeding device according to claim 2, wherein the wire rod feeding device is connected.   The at least 3 or more said feed mechanism parts are provided, The clamping force of the said wire by the said pair of roller was gradually enlarged as it went ahead of the feed direction of the said wire. The wire rod feeding device according to any one of the above.   5. A reduction gear is provided between the roller and the servo motor, and a pulley for locking the timing belt to an input rotation shaft of the reduction gear is pivotally supported. Wire rod feeder as described in 1.   The wire feeding device according to any one of claims 1 to 5, wherein the servo motor is an ultra-low inertia motor.

Images