JPH0123209B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method and apparatus for manufacturing a twist bar obtained by twisting and deforming a strip-shaped metal plate material in a fixed direction, and in particular to a method and apparatus for manufacturing a twist bar obtained by twisting and deforming a strip-shaped metal plate material in a fixed direction. It is possible to change it to .

[Conventional technology]

To form this type of twist bar, a material made of a band-shaped metal plate is inserted through a pair of fixed dies and a movable die, and one movable die is rotated in advance around the longitudinal center axis of the material A. It is known, for example, in Japanese Patent Publication No. 3958/1983 and Japanese Patent No. 127696, to initially set a predetermined twist pitch (lead angle) and then continuously form a twist bar with a constant pitch. .

[Problem that the invention seeks to solve]

By the way, the present applicant is planning to apply a strip-shaped twist bar as a member element that converts the vertical movement of the window into rotational motion in a counterbalance mechanism for a window, and in particular, the present applicant's proposal We have attempted to manufacture a twist bar (see FIG. 8) in which the twist pitch (lead angle) changes continuously, as disclosed in Japanese Utility Model Application Publication No. 126677/1983.

However, in the conventional example described above, the twist pitch can only be changed arbitrarily at the initial setting stage, and it is not possible to change the twist pitch during molding. Therefore, it has not been possible to achieve the desired result by changing the twist pitch in stages with one twist bar.

This invention has been proposed in view of the above, and an object of the present invention is to make it possible to reliably form a twist bar having a continuously different pitch in which the twist pitch changes continuously.

Another object of the present invention is to enable the twist pitch of the twist bar having a continuously variable pitch and the amount of change thereof to be set to arbitrary values.

[Means for solving problems]

The present invention uses a band-shaped metal plate material as a material A, and is provided with a chuck 13 that grips and fixes one end of the material A. This chuck 13 is rotatably supported around the central axis in the longitudinal direction of the material A. Preferably, means is provided for forcibly rotating the chuck 13 in the direction of twisting deformation of the twist bar T during molding.

A set of fixed dies 3B into which material A is inserted separately
and movable dice 3A, both dice 3
A feed drive means 5 is provided for relatively moving the chucks A, 3B and the chuck 13 in the direction of separation. In other words, the feed drive means 5 may move both dice 3A, 3B away from the chuck 13 (leftward in FIG. 1) as shown, or may move both dice 3A, 3B away from the chuck 13. It is also possible to move the chuck 13 side in the direction away from the chuck 13.

Thus, the pitch changing means 4 rotates one movable die 3A around the central axis of the material A.
0, and the pitch changing means 40 is used to change the inclination angle α of the movable die 3A in stages during machining.

[Effect]

As shown in FIG. 6, the fixed die 3B and the movable die 3A capture the material A having a rectangular cross section with different inclination angles. Specifically, the material A is captured so as to be immovable in both the thickness direction and the width direction, but movable only in the longitudinal direction.

In this captured state, material A is
When the inclination angles of A and 3B are very small, they are elastically deformed, but when the elastic deformation limit is exceeded, they are plastically deformed while still containing some elastic deformation. In other words, the material A undergoes plastic deformation while passing through both dies 3A and 3B, and the amount of torsional deformation changes depending on the magnitude of the relative inclination angle of both dies 3A and 3B. Therefore, when the movable die 3A is operated to change its inclination angle α, the twist bar T is formed while continuously changing the twist pitch P. Note that when passing through both dies 3A and 3B, the material A rotates in the direction of twisting deformation. Check 1 to follow this.
3 is rotatably supported.

To explain more specifically based on the illustrated example, in FIG.
3B, and its tip is held by chuck 13. Next, the pitch changing means 40 sets an initial twist pitch. In this way, while the feed driving means 5 moves both dies 3A and 3B to the left with respect to the chuck 13, the pitch changing means 40 changes the inclination angle α of the movable die 3A step by step.

[First Embodiment] FIGS. 1 to 8 show a first embodiment of the present invention applied to an apparatus for manufacturing twist bars with continuous different pitches used in a window counterbalance mechanism.

In FIG. 2, a headstock 2 that supports a spindle 1 and a die pedestal 4 that supports a pair of dies 3A and 3B are arranged side by side on one side of a base B of a predetermined height. There is.

The die stand 4 is supported by a feed drive means 5 provided on the base B, and is reciprocated in the longitudinal direction of the base B by the drive means 5.

The spindle 1 is driven to rotate at a constant speed by a geared motor 7 as a driving source via a clutch 8 and a belt transmission mechanism. 9 is the principle pulley, 10
1 is a belt, and 11 is a driven pulley fixed to the spindle 1.

A chuck 13 is attached to the shaft end of the spindle 1 on the side of the die stand 4. In FIG. 3, this chuck 13 includes a pair of upper and lower chuck pawls 14, 14 provided in the cylindrical shaft-shaped spindle 1, and a chuck shaft 16 for moving these chuck pawls 14, 14 in the axial direction of the spindle 1. , a chuck plate 17 that is attached to the side end of the spindle 1 and guides both chuck pawls 14 toward and away from each other in opposite directions; and the chuck shaft 1.
6 and a rotating cylinder 18 that moves the cylinder 6 forward and backward in the axial direction. The chuck 13 receives rotational power from the driven pulley 11 via the rotating cylinder 18 and the chuck shaft 16, and rotates together with the spindle 1. The chuck shaft 16 is connected to the chuck plate 17 by the rotating cylinder 18.
By operating to the side, both chuck claws 14 are guided by the tapered surface 17a of the chuck plate 17 and approach each other to grip and fix the material A.

In order to align the twist start positions of the twist bars T, a spindle positioning device 21 is provided below the driven pulley 11. In FIG. 4, this positioning device 21 includes an engaging pawl 22 supported on the headstock 2 so as to be able to swing up and down, a solenoid 23 that operates the engaging pawl 22 up and down, and a positioning device formed at one location on the circumferential surface of the driven pulley 11. and an engaging recess 24. When the spindle 1 rotates normally, the engaging pawl 22 is swung downward and is on standby.

In FIGS. 2 and 5, the feed drive means 5
has a pair of front and rear guide rails 26, 26, on which the die stand 4 is supported movably in the longitudinal direction of the rails via four slide blocks 4a. A feed screw shaft 27 is arranged above the front and rear center of the guide rail 26, and this is connected to the die stand 4.
It is screwed into a screw block 28 (see FIG. 3) attached to the die stand 4, so that the die stand 4 can be moved left and right. One end of the feed screw shaft 27 is rotatably supported by the headstock 2, and the other end is rotatably supported by a bearing 29 at the left end of the base B. 31, it is rotated in both forward and reverse directions. The transmission mechanism 30 uses a timing belt as a transmission medium.

In FIG. 3, a bearing stand 33 is placed on the die stand 4.
is fixed, a die shaft 34 is rotatably supported on a bearing stand 33, and a movable die 3A is fixed to the end on the spindle 1 side. Further, a fixed die 3B is fixed to the die stand 4 adjacent to the movable die 3A. A material insertion hole 37 is provided at the center of the die shaft 34 along the axis. As shown in FIG. 6, each of the dies 3A and 3B has a pair of die rollers 36 and 36 that sandwich the material A in the thickness direction in a die block 35 that is divided into upper and lower halves, and each roller 36 has a shaft. 39 so as to be rotatable in the material feeding direction. 38 is a width direction regulating piece.

A pitch changing means 40 is provided to continuously change the twisting pitch P of the twist bar T as shown in FIG. 8 by changing the tilt angle α of the movable die 3A. 2 and 5, the pitch changing means 40 includes a pinion gear 41 fixed to the left shaft end of the die shaft 34, and a rack 42 supported on the die stand 4 perpendicularly to the die shaft 34 and meshing with the pinion gear 41. The rack cylinder 43 for driving the rack 42 back and forth is used as an operating system, and is controlled by a control member described below to determine the inclination angle α of the movable die 3A.

During processing, the movable die 3A is marked with arrow C in Fig. 5.
A deformation reaction force acts in the direction shown by . This deformation reaction force acts to push the rack 42 in the direction of arrow D via the die shaft 34 and pinion gear 41. The aforementioned control member determines the moving position of the rack 42 using this acting force in the D direction. Specifically, a cam roller 44 is supported on the lower surface of the front end of the rack 42 via a shaft 44a so as to be rotatable around a vertical axis, and the front side surface of the cam roller 44 is received and supported by a control cam 45. The control cam 45 includes a group of cam blocks 45a, 45b, 45c, 45 as shown in FIG.
d and 45e, and is replaceably mounted on a cam bed 46 provided parallel to the guide rail 26. Each cam block (45a to 45e)
The cam surface with which the cam roller 44 comes into contact is set in a downward stepwise manner from the right end block 45a to the left end block 45e. As a result, the inclination angle α of the movable die 3A is large at the feed start end of the material A, and becomes smaller toward the feed end. In other words, the twist pitch P of the material A is small on the spindle 1 side and becomes larger as it moves away from the spindle 1. In the case of this embodiment, as shown in FIG.
It changes as mm.

In FIG. 7, reference numeral 47 is a guide pipe connected to the left end of the die shaft 34.

The material A is made of a stainless steel plate, and its approximate dimensions are 2 mm thick, 6 mm wide, and 950 mm long.
Spindle rotation speed is 30 times per minute, die stand 4
The feed rate is 50 mm per second, and the maximum tilt angle of the movable die 3A is 90 degrees.

[Operation explanation]

FIG. 2 shows a standby state in which the die stand 4 is adjacent to the spindle 1. In this state, the inclination angle α of the movable die 3A is set to zero, and the posture of the die rollers 36, 36 of the movable die 3A is made to match the posture of the die rollers 36, 36 of the fixed die 3B, as shown in FIG. Also, position the spindle 1 with the positioning device 21 as shown in FIG.
4 and 14 are placed in a position facing each other vertically. After this, the material A is inserted from the guide pipe 47 side, passed through the material insertion hole 37 and between the die rollers 36 and 36 of both dies 3A and 3B in order, and the insertion end is inserted between the chuck claws 14 and the rotating cylinder. Operate 18 and use chuck claws 14, 14 to remove material A.
Fix one end of.

After completing the above preparation work, the rack cylinder 43 is extended to bring the cam roller 44 into contact with the right end cam block 45a as shown in FIG.
With this operation, the tilt angle α of the movable die 3A is set to around 90 degrees, and the material A is twisted between the two dies 3A and 3B to receive an initial twist. Simultaneously with the completion of the initial setting operation of the cam roller 44, the spindle 1 and the feed screw shaft 27 are each rotationally driven, and the chuck 13 is rotationally driven while the die table 4 is fed and moved away from the spindle 1.

By the way, to avoid misunderstanding, the material A is not twisted and deformed by the rotational force of the spindle 1, but is twisted when the die stand 4 moves and the material A passes both dies 3A and 3B. undergo transformation. In other words, both the dies 3A and 3B are adjacent to each other, and the die rollers 36 and 3 that capture the material A are
6 are located very close to each other, the raw material A cannot communicate between the two die rollers 36, 36 unless it is plastically deformed beyond the elastic deformation limit between the two die rollers 36, 36. Therefore, both dice 3A, 3
Materials A coming into B one after another are passed through both die rollers 3
Both dice 3 while undergoing twisting deformation between 6 and 36
It will pass through A and 3B. At this time, the material A is subjected to a twisting deformation reaction force, and the material A is
A rotational force in the opposite direction to the twisting direction is generated between the die rollers 36 and 36, and the phase positions gradually shift between the two die rollers 36,
36, so material A is fixed die 3B
It is not twisted back when passing through. The spindle 1 is driven to rotate in order to assist the rotation of the material A and to reduce the rotational resistance force due to spring back that impedes rotation. The spindle 1 is rotated slightly ahead of the average rotational speed of the material A.

As the die stand 4 moves, the cam roller 44 comes into contact with the cam surface located forward of the previous stage cam surface as shown in FIG. 7, and the rack 42 moves in the direction of arrow D in FIG.
Shift in direction. The pinion gear 41 is now rotated in the direction of arrow C, and the die shaft 34 and movable die 3A rotate together. Figure 6 shows movable die 3A
is operated, and its inclination angle α is smaller than the initial state. In this way, when the inclination angle α of the movable die 3A becomes smaller, both the dies 3A,
Since the twist angle of the material A between 3B becomes smaller, the twist pitch P becomes larger. In addition, easy 4
The second cylinder 43 always presses the rack 42 in the extending direction from the start of machining to the end of machining.

Near the end of the material A, the feeding drive means 5 and the spindle 1 are stopped to complete the twisting process. After this, the operating force of the rack cylinder 43 is released, the chuck of the chuck 13 is released, the feed drive means 5 is driven in reverse to return the die stand 4 to the standby position, and the twist bar T is pulled out from the guide pipe 47. . Thereafter, the material A is set again and processed in the same manner as described above. As shown in FIG. 8, the resulting twist bar T has a twisting pitch P that is small at the chucking end, and the twisting pitch P becomes larger as it approaches the other end. Moreover, the twist pitch P changes smoothly.

As understood from the above description, by replacing the cam blocks 45a to 45e, it is possible to form a twist bar T of any shape in which the twist pitch P changes continuously. The cam surface of the control cam 45 can be formed into a straight line or a gentle curve, and does not need to be stepped as described above. If necessary, the cam surface shape can be set to a medium convex shape or a medium concave shape.

[Another embodiment example]

In the above embodiment, the material A is fixed by the chuck 13 and the die stand 4 is fed by the feeding drive means 5.
You can also perform the feed operation with .

The chuck 13 does not necessarily have to be rotationally driven. For example, if the deformation reaction force of the material A is small, it is sufficient to simply support it rotatably.

Dice rollers 36, 36 of both dies 3A, 3B
They can also be configured as a set of four as shown in FIG. Of course, both dies 3A and 3B do not need to be roller-structured dies, and can also have a block structure with die holes.

The material A can also be set by passing through the spindle 1 and feeding it from the chuck 13 side.

If necessary, heating means for facilitating plastic deformation of the material A may be provided on the material passage path to the movable die 3A.

〔Effect of the invention〕

In the present invention, the fixed die 3B into which the material A is inserted
and one movable die 3A among the movable dice 3A.
The pitch changing means 40 can be used to change the inclination angle α of The tilt angle α of the movable die 3A can be changed stepwise. Therefore, in one twist bar T, it is possible to reliably form a continuous variable pitch shape in which the twist pitch P changes continuously. Further, by simply adjusting the inclination angle α of the movable die 3A, the twist pitch P of the twist bar T and the amount of change thereof can be changed steplessly as desired, and a twist bar of a desired shape can be obtained.

Moreover, since the chuck 13 side is rotatably supported, it is sufficient to linearly reciprocate both the dies 3A and 3B side during machining without rotating them, thereby simplifying the structure.

[Brief explanation of drawings]

1 to 8 show a first embodiment of the present invention, in which FIG. 1 is a principle structural diagram conceptually showing the structure of a twist bar manufacturing apparatus, FIG. 2 is an overall plan view, and FIG. is a sectional view taken along the line E-E in Fig. 2, Fig. 4 is a partially cutaway front view of the headstock, Fig. 5 is a sectional view taken along the line F-F in Fig. 2, and Fig. 6 is a side view of the main parts of the die. , Figure 7 is a partial plan view during processing,
FIG. 8 is a front view of a twist bar obtained by the apparatus of the present invention. FIG. 9 is a side view of the main part of the die showing another embodiment of the die. DESCRIPTION OF SYMBOLS 1... Spindle, 2... Headstock, 3A... Movable die, 3B... Fixed die, 4... Die stand, 5... Feeding drive means, 13... Chuck, 3
4...Dice shaft, 36...Dice roller, 37...
...Material insertion hole, 40...Pitch changing means, A...
Material, L...adjacent spacing, P...twist pitch, T...
...Twist bar, α...Tilt angle.

Claims (1)

[Scope of Claims] 1. A chuck 13 that fixes one end of a material A made of a band-shaped metal plate material and is rotatably supported around the longitudinal center axis of the material A, a fixed die 3B through which the material A is inserted, and A movable die 3A, a feed drive means 5 for relatively moving the two dies 3A, 3B and the chuck 13 in the direction of separation, and a rotating operation for rotating the movable die 3A around the central axis of the material A to move the movable die 3A during processing. Inclination angle α
This apparatus includes a pitch changing means 40 for changing the pitch in stages. 2. The apparatus for manufacturing a twist bar with continuous different pitches according to claim 1, wherein the chuck 13 is configured to be forcibly rotated in the direction of twisting deformation of the twist bar T.