JP2777687B2 - Pre-processing method and pre-processing device for wire rod - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a device for forming a coil spring with high precision by preliminarily processing a wire for forming a wire into a coil spring in a coil spring manufacturing machine.

[0002]

2. Description of the Related Art As shown in FIG. 7, a forming tool 9 applies bending stress to a wire 4 supplied by a guide member 3 in order to apply a desired initial tension to a body coil portion 32 wound tightly around a tension coil spring 31. Is applied to form the body coil portion 32. As another pre-processing method, the guide member 3
Before the wire 4 is supplied to the wire, a tension coil spring is formed while a bending stress is always applied to the wire 4 at a predetermined radius of curvature R.

[0003]

According to the prior art, in order to obtain an initial tension of a tension coil spring, a bending stress is always applied to a wire before processing. As a result, a bending stress is also applied to the wire corresponding to the hook portion of the tension coil spring, so that the leg portion of the hook is bent or the arc portion is deformed, and the shape of the spring becomes a desired flat or linear shape. did not become.

In order to solve this problem, when a wire is sandwiched between a pair of upper and lower feed rolls and supplied to a guide member, a thrust load is applied to each of the upper and lower feed rolls in an axial direction opposite to each other, so that the facing feed sandwiches the wire. A bending stress is applied to the wire rod by eccentricizing the axis of each groove of the roll.

[0005]

FIG. 1 shows a feed roll apparatus, in which a bearing member 2 of one feed roll shaft supported by a female screw 8 built in a frame 1 is rotated by a second servomotor 12. To control the thrust load.

[0006] When feeding a wire of an amount necessary to form one tension coil spring by a feed roll device, the feed rolls are opposed to each other in a partial wire feed corresponding to a hook portion that does not require initial tension. Eliminates axial thrust load and does not apply bending stress to wire.

[0007]

Since the wire rod 4 as a strand is wound into a ring-shaped bundle, the wire rod itself has a circular arc-shaped bending habit. When the wire 4 is returned to a straight shape by passing through the straightening device, an arc shape remains on the wire 4 due to the remaining bending habit and straightening stress.

The ring-shaped bundle is mounted horizontally or vertically with respect to the space in which the spring of the spring forming machine is formed, or vertically and horizontally away from the axis of the guide member 3 to form the spring. When the relative positional relationship with the wire of the annular bundle is changed, the flow direction of the wire 4 sent out from the guide member 3 naturally changes.

On the other hand, by fixing the relative position,
The flow direction of the wire 4 is also fixed, and the upper feed roll 15 is fixed.
3 is moved in a thrust manner, the contact of the wire 4 shown in FIG. 3 with the upper groove 17 of the upper feed roll 15 and the lower groove 18 of the lower feed roll 16 is shifted by the amount of thrust load, and the wire 4 is sent out via the guide member 3. In the space where the spring to be formed is formed, the flow destination changes in a three-dimensional direction as shown in FIG. The direction of the change and the degree of the bending amount are applied to preliminary processing for forming a tension coil spring requiring initial tension.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. The rotation of the second servo motor 12 rotates the moving male screw 7 constituting the linear motion part 6 via the gear which is the rotary motion part 5. The bearing member 2 rotatably and non-slidably connected to the upper feed roll shaft 13 has a moving male screw 7 forming the bearing member 2 and a female screw 8 forming the linear motion part 6 machined on the frame 1. It slides in the axial direction of the upper feed roll shaft 13. The lower feed roll 16 holding the wire 4 does not move in the thrust direction.

The lower feed roll shaft 14 is rotated by the first servo motor 11. Since the upper feed roll shaft 13 is meshed with the lower feed roll shaft 14 by connecting gears 19 and 20, it is fixed to the upper groove 17 of the upper feed roll 15 fixed to the upper feed roll shaft 13 and to the lower feed roll shaft 14. The wire 4 sandwiched by the lower groove 18 of the lower feed roll 16 is sent out to the spring forming space via the guide member 3. The pair of feed rolls is provided with a pressing force as a gripping force for appropriately feeding the wire 4 by a pressing device (not shown) in a direction in which the wire 4 is pressed. In the spring forming space, the tension coil spring 31 is formed with a plurality of tools (not shown).
As shown in FIG. 4, the wire 4 flows out in any one of directions A, B, and C according to the thrust state.

In FIG. 3, when the thrust-moving upper feed roll 15 is moving to the left with respect to the lower feed roll 16, the wire 4 flows in the direction of the left-hand side a. This bending property of the wire 4 is a preliminary process for applying initial tension to the body coil portion 32 of the extension coil spring 31.

In FIG. 2, since the upper feed roll 15 does not move in the thrust direction, the wire 4 flows in the same direction as the axis of the guide member 3, and the wire 4 has no bending characteristics.

When the hook portion 33 of the extension coil spring 31 is formed in this state, the arc portion 34 is not deformed, and the leg 35 moves straight, so that the ideal extension coil spring 31 is formed.

[0015]

According to the present invention, when the wire rod 4 is not constantly bent and each portion of the tension coil spring 31 formed during operation of the spring forming machine is bent or removed as needed, the wire rod 4 is formed. A high-precision tension coil spring 31 is completed. In addition to tension coil springs with initial tension, pitch winding springs and compression springs also use a measuring device such as a length detector to control the thrust load and adjust and manage the pitch interval of the body coil. can do.

[Brief description of the drawings]

FIG. 1 is an overall explanatory view of the present invention.

FIG. 2 is a partial view of a feed roll to which no thrust load is applied.

FIG. 3 is a partial view of a feed roll to which a thrust load is applied.

FIG. 4 is an explanatory view showing a flow method of a wire rod.

FIG. 5 is an explanatory view of an appropriately shaped tension coil spring.

FIG. 6 is an explanatory view of a tension coil spring having an unfavorable shape.

FIG. 7 is an explanatory view showing a conventional technique.

[Explanation of symbols]

 Frame 1 Bearing member 2 Guide member 3 Wire rod 4 Rotary moving part 5 Linear moving part 6 Moving male screw 7 Female screw 8 Forming tool 9 Numerical control device 10 First servo motor 11 Second servo motor 12 Upper feed roll shaft 13 Lower feed roll Shaft 14 Upper feed roll 15 Lower feed roll 16 Upper groove 17 Lower groove 18 Connecting gear 19, 20 Tension coil spring 31 Body coil part 32 Hook part 33 Arc part 34 Leg part 35

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Claims (2)

(57) [Claims] 1. A wire feeding method of a spring forming machine for feeding a wire pinched by a pair of feed rolls from a guide member, wherein the pair of feed roll shafts supporting the pair of feed rolls for wire feeding, the pair of feed roll shafts. A first rotation speed controllable servomotor that rotates at least one of the feed roll shafts, and a bearing member in which one of the pair of feed roll shafts is connected rotatably and non-slidably, A conversion mechanism configured by a rotary motion part and a linear motion part to convert the rotary motion into a linear motion along the advancing and retreating direction of the bearing member; and a second stop position and a rotation speed for driving the rotary motion part of the conversion mechanism. The pair of feeds sandwiching a wire by a controllable servomotor and a numerical controller that controls the first and second servomotors according to a set number of pulses. Preliminary processing method of the wire which is eccentric axis of the groove of the roll and wherein the providing a bending stress to the wire. 2. A wire feed roll device of a spring forming machine for feeding a wire held between a pair of feed rolls from a guide member, comprising: a pair of feed roll shafts supporting a pair of feed rolls for feeding a wire; A first stop position for rotating at least one of the feed roll shafts and a controllable rotation speed servomotor, and one of the pair of feed roll shafts is connected rotatably and non-slidably. A bearing member, a conversion mechanism including a rotary motion portion and a linear motion portion for converting the rotary motion into a linear motion along the reciprocating direction of the bearing member, and a second stop for driving the rotary motion portion of the conversion mechanism. A servo motor capable of controlling the position and the rotation speed; and a numerical controller for controlling the first and second servo motors according to a set number of pulses. Preliminary processing apparatus of the wire to be.