JPH01293920A - Bending device - Google Patents

Abstract

PURPOSE:To finely and complicatedly bend a bar, a pipe, etc., by moving a movable carriage so that intervals between bending heads and a fixed head are adjusted according to the bending speeds of the bending heads in a bending time. CONSTITUTION:A pipe P that is a material to be worked is gripped by a fixed head 10. The pipe P is gripped and bent by bending heads 20L, 20R along a bending die. The bending heads 20L, 20R are traveled on the movable carriages 30L, 30R. The movable carriages 30L, 30R are moved and bent at the same time so that intervals between the bending heads 20L, 20R and the fixed head 10 are adjusted according to the bending speeds of the bending heads 20L, 20R in a bending time. Hereby, a material to be worked in the shape of a bar, pipe can be worked finely and complicatedly.

Description

[Detailed Description of the Invention] Purpose of the Invention [Field of Industrial Application] The present invention relates to a bending device, and particularly to a so-called draw-bend type bending device that bends a workpiece while holding it between a bending die and a clamping die. This invention relates to a bending device.

[Prior Art] Conventionally, a draw vent type bending device has been known as a single bender.
Devices described in Japanese Patent Publication No. 2549, Japanese Patent Publication No. 62-22693, and Japanese Utility Model Application No. 62-86911 are known.

In the apparatus described in each of the above-mentioned publications, the fixed head is moved toward the bending head as the bending head performs the bending process at a predetermined position. The device described in Japanese Patent Publication No. 53-42549 is equipped with a comprehensive member between a fixed head and a bending head, and the bending head attracts the fixed head to perform bending. In the described apparatus, the fixed head was equipped with an automatic feeder, and the bending process was performed while approaching the bending head by self-propelled movement.

Regarding the bending device called a double-headed bender, for example, the device described in Japanese Patent Publication No. 52-20026 is known, but it is a so-called compression bend type, and a draw bend type bending device has not been invented yet. There wasn't. This is because, as mentioned above, there is a known drawbend type in which the fixed head is moved toward the bending head side, but in a double-headed bender, it is impossible to move the fixed head.

[Problems to be Solved by the Invention] According to the above-mentioned conventional device, in a single bender, a force that tries to pull the workpiece and the fixed head is applied to the bending head, so the clamping mold Also, an external force in the axial direction of the workpiece acts on the bending die, and there is a risk that the workpiece may slip and shift at the gripping portion. Therefore, in order to reliably grip the workpiece with the clamping die and the bending die, it was necessary to increase the so-called clamp width. As a result, there has been a problem in that fine and complicated bending cannot be performed.

In addition, in the case of a double-headed bender, the above-mentioned conventional equipment
Because it is a compression bend type, the clamp width of the clamp used to press the workpiece into the bending die must be increased to match the maximum arc length. Therefore, similar to the problem with the single bender mentioned above, fine and complicated There was a problem that bending was not possible.

Structure of the Invention The present invention has been made for the purpose of solving such problems, and has adopted the following structure.

[Means for Solving the Problems] That is, the gist of the present invention is to provide a fixed head for gripping a rod-shaped or pipe-shaped workpiece, and a bending mold for the workpiece gripped by the fixed head. a bending head that bends along the bending die while being held by a clamping die, and a movable table on which the bending head is placed and the distance between the bending head and the fixed head can be adjusted; In a bending device that bends a workpiece into a desired shape, during bending, the bending head is configured to adjust the distance between the bending head and the fixed head in accordance with the bending speed of the bending head. A bending device is characterized in that it is configured to perform bending while moving a movable table.

[Function] According to the bending apparatus of the present invention, the distance between the bending head and the fixed head is adjusted by moving the movable table closer to the fixed head in accordance with the processing speed of the bending head. Performs draw bend type bending. That is, the clamping die and the bending die are not subjected to any force that tends to displace the workpiece in the axial direction, unlike in conventional devices, so it is possible to reduce the clamping width. As a result, fine and complicated bending is possible.

"Example] Next, embodiments of the present invention will be described based on the drawings.

FIG. 1 shows a schematic front view of a double-headed drawbend type bending device (hereinafter simply referred to as a bending device) 1 as an embodiment.

The bending device 1 includes a support frame 5 having a single linear rail 3, a fixed head 10 disposed approximately in the center of the support frame 5,
Bending heads 2OL, 2OR1 bending heads 2OL, 2O are arranged on the left and right as shown in the figure with the fixed head 10 at the center.
It consists of a movable table 301.30R on which R is placed and movable along the rail 3, and movable motors 40L and 40R that move the movable table 301.30R in the left-right direction in the drawing. Furthermore, an air cylinder 50 for aligning the pipe P, which is a workpiece, is disposed at the left end of the support frame 3 in the drawing.

The fixed head 10 includes a chuck 60 and a rotary motor 80, which will be described in detail later. A tightening motor 90 is provided.

In addition, as shown in FIG. 2, the bending head 2OR has a bending shaft 2.
It is provided with a bending arm 23R that is rotated as shown by an arrow A in the figure by a hydraulic cylinder 22R about 1R. Bending axis 21R
is provided with a bending arm 24R having a groove matching the outer diameter of the pipe P and having a clamp piece 24Ra, and the bending arm 23R has a similar groove at a position facing the clamp piece 24Ra. A clamping die 25R is provided. Clamping mold 25R is shown - Hydraulic cylinder 26R installed on the right side
It is driven forward and backward relative to the bending die 24R as shown by the arrow B in the figure, and grips the pipe P in cooperation with the bending die 24R. In addition, the pressure mold 27R is installed in parallel with the clamping mold 25R, and the pressure mold 27R is installed in parallel with the clamping mold 25R.
R is driven forward and backward by the hydraulic cylinder 28R as shown by the arrow C in the figure, and presses the pipe P held by the bending die 24R1 and the clamping die 25R downward in the figure, thereby suppressing the lifting of the pipe P during bending. . These bending molds 24R, clamping molds 25R, and pressure molds 27R are provided to be replaceable depending on the workpiece.

Furthermore, the vertical frame 31R of the movable table 30R is provided with a payout member 33R that is driven in the direction of the arrow in the figure by a hydraulic cylinder 32R, pushes up the pipe P that has been bent, and pays it out from the bending head 2OR. Further, the movable table 30R is driven by a movable motor 40R via a subrocket 1-41R and a chain 42R, and can be moved to any position along the rail 3. Although FIG. 2 and the above description have been made regarding the right bending head 20R, the left bending head 201- has a similar configuration.

Next, the structure of the chuck 60 disposed on the fixed head 10 will be explained based on FIGS. 3 to 7.

The chuck 60 is rotatably supported by the support frame 12 of the fixed head 10. The support frame 12 is formed of a thick steel plate,
It has a circular notch 14 in the center, and the circular notch 14 has an opening 16 on the right side in the figure.

The support frame 12 also includes six support rollers 18a to 18f arranged concentrically at equal intervals around the outer periphery of the circular notch 14 and fixed with hexagonal bolts.

The chuck 60 serves as a rotating body and includes support rollers 18a to 18a.
Rotating disk 6 whose outer periphery is rotatably supported by 8f
1. The rotary disk 61 has a notch 62 of a predetermined width formed from a predetermined position on the outer circumference L to the center. Further, near the outer periphery of the rotating disk 61, a ring-shaped gear 63 formed with a slightly smaller radius is provided to protrude toward the front in the drawing. Further, on the rotating disk 61, gripping members 64a and 64b which are movable into and out of the notch 62 are provided at right angles to the notch 62 and above and below in the drawing. Gripping members 64a, 64. b is a replaceable gripping piece 65a at the tip
, 65b, and the protective frames 66a and 66b are fixed to the rotary disk 6 from the front direction in the figure by tightening bolts.
covered with.

The gripping members 64a and 64b have an engagement step 6 in the entry direction at one end.
7a, 67b, and a backward engagement step 68a at the other end.
The recesses 69a and 69b are provided. In the recesses 69a and 69b, there are engagement step portions 67a and 67 in the advancing direction.
b or backward direction engagement step portion 68a.

Swing lever 7 that engages with 68b and drives the gripping member forward and backward.
The heads of 0a and 70b are inserted. Swing lever 70
a and 70b are connected to the swinging member 7 via links 71a and 71b.
It is connected to 2. When the swing member 72 swings clockwise around the swing shaft 73 in FIG.
, the gripping members 64a and 64b can move or swing to grip the pipe P.

A rotary motor 80 is provided as a rotary drive member for rotationally driving the rotary disk 61, a rotary drive gear 82 is installed on the motor shaft 81 of the rotary motor 80, and a rotary drive gear 82 is provided between the rotary drive gear 82 and the ring-shaped gear 63. A first engagement gear 83 and a second engagement gear 84 are provided, which are two engagement members that engage with both of them.

Engagement position X between the first engagement gear 83 and the ring gear 63
The first and second engaging gears 83, 84 and A rotational drive gear 82 is provided.

Furthermore, the chuck 60 is equipped with a driving member for a swinging member 72, which will be described below.

As shown in FIGS. 5 to 7, four ring support rollers 74a to 74f are provided on the back surface of the rotating disk 61 at equal intervals on a concentric circle.
The boss 75, into which the swing shaft 73 is fitted, is also fixed with bolts. The swing shaft 73 has bearings 76a provided at both ends of the post 75.
, 76b. Further, the swing shaft 73 is integrally provided with a lever 77 bolted to the lower end side in FIG. 5, and the lever 77 is provided with an engaging protrusion 78 at the tip. The lever 77 is swung by a tightening ring 91, which will be described next, and is operated as shown in FIG.
, 64b to execute the gripping/releasing operation.

As shown in FIG. 7, the tightening ring 91 is a partially cut-out ring equipped with a gear 92 on its outer periphery and has an open part 93 with the same width as the cut-out width of the cut-out part 62.
It is rotatably supported from the inside of the ring by ~74f.

Furthermore, two engaging protrusions 94a and 94b that engage with the engaging protrusion 78 in a sandwiching manner are arranged at predetermined positions on the tightening ring 91. Opening section 93. Engagement protrusion 94a
.

The arrangement of the gripping members 64a and 64b is such that, as shown in FIG. 7, when the opening portion 93 coincides with the cutout portion 62, the gripping members 64a and 64b are brought to the pipe opening position via the lever 77.

The tightening ring 91 having the above configuration is driven to rotate in forward and reverse directions by the two tightening engagement gears 95 and 96 that engage with the gear 92 and the tightening drive gear 9B provided on the motor shaft 97 of the tightening motor 90. As shown in FIG. 4, gripping members 64a, 64
The pipe P is gripped and released by b. The tightening engagement gears 95 and 96 and the tightening drive gear 9B are arranged in parallel with the engagement gears 83 and 84 and the rotary drive gear 82, as shown in FIG.

The bending apparatus 1 further includes a control device 100 as a processing control means, and is configured to execute bending based on bending command information input from a command device 110.

As shown in FIG. 8, the control device 100 includes a CPU 101,
ROM102. It is configured as a logic operation circuit mainly including a RAM 103 and the like, and is connected to an input port 105 . It is connected to the input/output boat 106 and performs input/output with the outside. Further, the control device 100 has an input port 10
Based on the bending command information inputted from the command device 110 via the input/output boat 106, the hydraulic cylinder 22L is
, 22R, 261, 26R, 28L, 28R.

Servo valve 22La installed in 32L and 32R,
22Ra, 26La, 26Ra, 28La.

It outputs a drive signal to 28Ra, 32La, 32Ra, and each position sensor 22Lb, 22Rb.

26Lb, 26Rb, 28Lb, 28Rb, 3
Detection signals from 21-b, 32Rb are manually input. Similarly, the moving motors 40L, 40R, rotation motor 80. Tightening motor 9
Servo motor 40La provided at 0.

40Ra, 80a, 90a, and position sensors 40Lb, 40Rb, 80b,
Detection signals from torque sensors 40Lc, 40Rc, and 90b are input.

Next, the effects of the bending device 10 having the above configuration will be described.

To perform bending with the bending device 1, first, the pipe P is inserted into the notch 62 of the chuck 60 from the direction of the drawing plane in FIG. 1, that is, from the right side in FIG.
After positioning the tightening motor 90 between the tightening drive gears 98 and 98.b, the tightening motor 90 is driven. The clamping ring 91 is rotated in the gripping direction via the clamping engagement gears 95 and 96. Then, the engaging protrusion 9
4a and 94b, the lever 77 is rotated in the gripping direction, and the gripping members 64a and 64b enter the notch 62 as shown in FIG. hold on to. After that, drive the moving motor 40R,
Each bending head 2OR is moved to a predetermined bending position, and the hydraulic cylinder 26R is driven to grip and hold the pipe with the bending die 24R and the clamping die 25R. At the same time, the hydraulic cylinder 28R is driven to press the pressure mold 27R against the pipe P.

A similar operation is performed on the left bending head 2OL, and the pipe P is fixed on the fixed head 10. It is held by the bending heads 2OL and 2OR and becomes ready for bending. Here, the tightening motor 90 is kept energized so that a slight torque is applied in the gripping direction so that the gripping force by the gripping members 64a and 64b does not weaken.

Bending is then performed. In addition, although the following description will be made regarding only the right bending head 20R, the bending process is similarly performed on the left bending head 20L.

In the bending head 2OR, the bending arm 23R is rotated to a desired angle by the hydraulic cylinder 22R. pipe P
The clamp piece 24Ra of the bending die 24R and the clamping die 25R
While being held by the pressure die 27R, the part on the side of the fixed head 10 from the grasping position is wrapped around the concave groove of the bending die 24R and bent to a desired angle.
This prevents the wrapped portion of the pipe P from floating upward in FIG. 2. Here, as shown in the previous example, the bending device 1 uses a draw bend method, so
In connection with the above bending process, it is necessary to adjust the distance between the bending head 2OR and the fixed head 10 in the approaching direction as shown by the dotted chain line in FIG.

Therefore, in the above bending process, the following processing is executed by the control device 10O. In addition, even when changing the bending direction, the control device 100 performs control to reduce the pipe gripping force and prevent the bending direction from becoming inaccurate due to displacement of the pipe. Hereinafter, bending control using the draw bend method and chuck rotation control when changing the bending direction will be explained based on FIGS. 9 and 10. For simplicity, the processing and operations common to the left and right bending heads 2OL and 2OR will be described only for the right bending head 2OR.

First, the command device 110 inputs bending command information such as the bending position, bending direction, bending angle, material, diameter, and wall thickness of the pipe. Then, the bending control shown in FIG. 9 is executed.

At step 200, various variables and flags are initialized.

Next, in step 210, the bending heads 201.2OR are each moved to a predetermined bending position. position sensor 40
When it is confirmed by the detection signals from Lb and 40Rb that it has been moved to a predetermined position, the process proceeds to step 220. In step 220, the hydraulic cylinders 26R and 28R are driven, and the pipe P is gripped by the bending head 20R. In the following step 230, the hydraulic cylinder 22R is driven, and the bending arm 23R is rotated clockwise in FIG.

At the same time, the moving motor 40R is driven, and the moving table 30R is moved to the left in FIG. At this time, the rotational speed d O/d t of the bending arm 23R and the moving speed dX of the moving table 30R
/dt is the position sensor 28R so that the relationship of the following formula is satisfied.
b, is controlled based on the detection signal of 40Rb.

dx/dt=R-dθ/dt+a (1) where: R...Radius α to the bottom of the concave groove of the bending mold 24R...Minimum speed. In equation (1), the moving table 30R only moves at a minute speed α.
By making the moving speed of the bending arm 23R slightly faster than the rotating speed of the bending arm 23R, the pipe P is bent while applying a slight compressive force. By applying a slight compressive force in this way, it is possible to reduce the bending resistance force applied to the bending arm 23R, and also to eliminate bending errors caused by the elongation of the pipe P as it is bent. Furthermore, dθ/dt,
The value of α changes depending on the material, diameter, wall thickness, etc. of the pipe.

In the following step 240, it is determined whether the output 1 to rook of the moving motor 40R detected by the torque sensor 40RC during the movement is less than or equal to a predetermined value.

That is, if the above-mentioned 1 Herc becomes more than a predetermined value, the above-mentioned compressive force applied to the pipe P during bending becomes too large, and this is to prevent the pipe P from buckling. If a negative determination is made in step 240, the process proceeds to step 250, where the current applied to the moving motor 40R is limited, thereby preventing the buckling, and the process proceeds to step 260, as in the case where an affirmative determination is made in step 240.

In step 260, it is determined whether one bending process has been completed or not. If the bending process has not yet been completed, the processes from step 230 onwards are repeated, and if the bending process has been completed, the hydraulic cylinder 22R2 is moved in step 270. motor 40
R is stopped. In the following step 280, the hydraulic cylinders 26R and 28R are driven, and the clamping mold 25R1 pressure mold 27
The gripping force on the pipe P by R is released, and
The hydraulic cylinder 32R is driven, the pipe P is pushed upward by the payout member 33R, and the process ends.

After one bending process is completed as described above, if a second bending process is required at another position, the process shown in the flowchart of FIG. 9 is executed again. Here, when performing bending in a direction different from the first bending direction using the second bending device, the 10th
The chuck rotation control process shown in the figure is executed.

Here, the information regarding the bending direction is inputted by the command device 110 as described above, and the process is started.

First, in step 300, various variables, flags, etc. are initialized. Next, in step 310, the servo motor 80a
is driven, and the rotary motor 80 is driven to rotate based on the information regarding the bending direction.

Subsequently, in step 320, it is determined whether the output torque of the tightening motor 90 detected by the torque sensor 90b is greater than or equal to a predetermined value. If the determination is affirmative, step 340
If the determination is negative, the process advances to step 330.

In step 330, control is performed to increase the current supplied to the servo motor 90a and make the output torque of the tightening motor 90 equal to or higher than a predetermined value, and the process proceeds to step 340. In step 340, it is determined whether the rotational position of the rotary motor 80 detected by the position sensor 80b, that is, the rotational position of the chuck 60, has reached a position corresponding to the bending direction information. If it has not yet rotated to the desired position,
The process returns to step 310 and the above-described control is continued. on the other hand,
If the rotation has reached the desired rotational position, the process advances to step 350, where the power supply to the rotary motor 80 is stopped and the current supplied to the tightening motor 90 is maintained at a predetermined value, that is, until the pipe P is gripped and held. The value is returned to the required value and processing ends.

Here, the first. The second engagement gear 83 , 84 has a notch 62 .
For example, even when the first engagement gear 83 is located in the notch 62, the second engagement gear 84 is engaged with the ring-shaped gear 63 at an interval larger than the notch width. The chuck 60 can be reliably engaged with the gear 63 to further rotate the chuck 60 in a desired direction. Tightening engagement gear 95.9
6 and the tightening ring 91 are also similar, and can continue to transmit the tightening force to the gripping members 64a and 64b regardless of the position of the open portion 93.

As explained above, according to this embodiment, it is now possible to perform draw bending even with a double-headed bender. That is, since bending can be performed while moving the bending head 201°2OR toward the fixed head 10 according to the amount of bending and the bending speed, the clamp width, that is, the width of the clamping die 25R and the clamp piece 24Ra can be reduced. It became possible to do so. As a result, it is possible to perform fine and complicated bending. Also, a moving motor 40L.

40R is equipped with torque sensors 40LC and 40RC, and while detecting the output torque, a slight compressive force is applied in the axial direction of the pipe P to slightly move the movable tables 30L and 30R, thereby reducing the load applied to the bending arm 23R. In addition, the bending process can be performed so that the pipe P does not buckle.

Furthermore, by inputting the material, diameter, wall thickness, etc. of the pipe P from the command device 110 and changing the bending speed dθ/dt and minute speed α accordingly, various pipe materials can be processed efficiently at the optimum processing speed. Can be bent.

Further, since the chuck 60 can be rotated in forward and reverse directions without any restriction in its rotation range, the working efficiency of bending can be improved. Furthermore, a fixed head 10, a bending head 2O
Pipe P from the first drawing surface direction to both L and 2OR
Since it can be attached and detached, it is possible to automate the work. Furthermore, by providing the dispensing member 33R and the air cylinder 50, it is possible to completely automate the process.

Although one embodiment of the present invention has been described above, the present invention is not limited to this in any way, and various embodiments can be adopted without departing from the gist thereof.

For example, the moving tables 30L and 30R have chains 42L and 42
Instead of R, it may be driven by a screw gear or the like. In addition, the human-powered device 110 may be equipped with a material selection button and an adjustment volume so that at least one of the above-mentioned processing command information can be input. Further, instead of the control processing by the control device 100, for example, the movement motors 40'', 40R may be hydraulically driven to fixedly control the opening amount of the servo valve, and the hydraulic cylinder 22R may be The opening amount of the servo valve 22Ra may be synchronized with the opening amount of the servo valve 22Ra.

The moving speed dx/dt may be set as follows: dx/dt=R-dθ/dt (2), and no compressive force in the axial direction is applied to the pipe P. Also, torque sensor 40Lc.

There is no need to perform control using 40Rc.

The direction of rotation of the bending arm 23R may also be such that the bending process is performed by rotating from the bottom to the top, and in this case there is an advantage that the upper space can be used effectively. Similarly, the chuck 6 shall be rotated in the horizontal direction.
The notch 62 of 0 may be configured to allow the pipe to be attached and detached from above.

Further, in place of the engaging gears 83, 84 and the tightening engaging gears 95, 96 of the chuck 60, rubber rollers or the like may be used to engage with the outer circumference of the rotating body by frictional force and drive the rotating body to rotate. Good too. Further, the gripping member may be moved forward and backward by tightening and loosening using a bolt or the like. In addition, by employing a bending die 24R2 having a heart-shaped groove as the tightening die W25R, it is possible to prevent the pipe from collapsing when bending an ultra-thin steel pipe or the like.

As described in detail, according to the present invention, it is possible to perform bending using the draw-bent method even with a double-headed bender, and it is possible to reduce the clamp width for both double-headed and single-headed bender, making it possible to perform finer and more complex work. Bending processing is now possible.

[Brief explanation of the drawing]

Fig. 1 is a schematic front view of the bending device having the chuck of the embodiment, Fig. 2 is a front view of the bending head thereof, Fig. 3 is a left side view of the chuck, and Fig. 4 is the function of the gripping member. FIG. 5 is a sectional view taken along line AA in FIG. 3, FIG. 6 is a sectional view taken along line BB in FIG. 5, and FIG. 7 is a right side view of the chuck.
FIG. 8 is a block diagram showing the configuration of the control device of the bending device, FIG. 9 is a flowchart of bending control, and FIG.
The figure is a flowchart of chuck rotation control. 1...Bending processing device 10...Fixed head 2OL, 2OR...Bending head 24R...Bending die 25R...Clamping die 301.3OR...Moving table Agent Patent attorney Tsutomu Sadadate (Baka 1) name) = 25-

Claims (1)

[Scope of Claims] A fixed head that grips a rod-shaped or pipe-shaped workpiece, and a bending die and a clamping die that hold the workpiece held by the fixed head while holding the workpiece along the bending die. A bending device that bends a workpiece into a desired shape. In the bending process, the bending process is performed while moving the movable table so as to adjust the distance between the bending head and the fixed head in accordance with the bending speed of the bending head. A bending device characterized by the following.