JPS644852B2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a novel press brake,
More specifically, the present invention relates to a press brake that always maintains a balanced state of a movable ram provided opposite a fixed table in a hydraulic press, thereby enabling highly accurate machining.

Generally, in this type of machine tool, when machining is performed by bringing a long ram close to a fixed table, the long ram must always maintain equilibrium with the fixed table as it approaches. You need to move it while doing so.

In addition, in the case of press working, applying an equal pressing force in the longitudinal direction of a long ram is difficult because of the unevenness of the materials. Even if there were, the plate thickness would be different in the longitudinal direction, making it impossible.

Furthermore, due to the non-uniformity of the pressing force, the long ram tilts upward to the left or upward to the right, making it impossible to maintain equilibrium with the fixed table, resulting in variations in the product.

Particularly in the case of bending, there were problems with variations in left and right bending angles, product combinations, and product accuracy.

Various measures have been taken in the past to solve this problem, but no effective solution has yet been proposed.

The present invention effectively solves these conventional problems, and its purpose is to provide pressure passages connecting the fluid pressure operating devices provided on both sides of the movable ram and the pressure fluid supply device. In addition to providing a switching valve, this switching valve is controlled according to the deformation of the movable ram during processing, and the movable ram is always balanced and corrected with respect to the fixed table, improving the accuracy of press processing. The present invention provides a press brake that allows the

Another object of the present invention is to always control the movable ram in equilibrium with respect to the fixed table, and
To provide a press brake that accurately controls the lifting stop position of a movable ram.

Hereinafter, a preferred embodiment of the present invention will be described based on the accompanying drawings.

1 and 2 show a schematic front view and a side view of a press brake 1 according to the present invention, and this press brake 1 is mounted on a fixed table 5 provided on the upper part of a machine frame body 3, for example. This is a so-called hydraulic press in which a movable ram 7 moves up and down.

The movable rams 7 are provided on both sides of the machine frame main body 3.
Two C-shaped frames 9 are located on the back side of the
a and 9b are integrally attached, and a bottom plate 11 is integrally fixed to the bottom.

At the lower center of the C-shaped frames 9a, 9b, fluid pressure actuators 13a, 13b such as hydraulic cylinders are provided for raising and lowering the movable ram 7 with respect to the fixed table 5.

The tips of the piston rods 15a, 15b of the fluid pressure actuators 13a, 13b are connected to both sides of the bottom of the movable ram 7 via a connecting member (not shown) such as a spherical body, and the movable ram 7 is connected to the machine frame body. It is guided in the front-rear direction in FIG. 1 via a guide member (not shown) such as a roller fixed to 3.

Note that the guide member may be a member other than the roller that makes surface contact.

Further, at an intermediate position between the fluid pressure actuating devices 13a and 13b, that is, at a central position of the movable ram 7, a roller (not shown) for regulating the center position of the movable ram 7 is provided.
is provided. The roller moves along the movable ram 7 along a guide groove (not shown) provided in the vertical direction.
It moves up and down together with the movable ram 7, and restricts the movement of the movable ram 7 in the left-right direction. Also,
When the movable ram 7 tilts upward to the left or downward to the left in FIG. 1, the movable ram 7 tilts with the roller as the center of rotation.

A protruding member 1 is provided on the lower surface of both ends of the movable ram 7.
7a, 17b and pins 19a, 19b, one end of the connecting members 21a, 21b is rotatably connected, and the other end of the connecting members 21a, 21b is
It is rotatably connected to lever members 27a and 27b integrally provided at both ends of a torsion bar 25, which will be described later, via pins 23a and 23b.

Pins 2 are provided at both ends of the torsion bar 25.
One end of link members 31a, 31b, which is referred to as a link mechanism, is rotatably connected via 9a, 29b, and each link member 31a, 31b
The other end is rotatably supported via a pin 35 on a bracket 33 fixed to the bottom plate 11 of the machine frame body 3.

The pin 35 is preferably rotatable or has a spherical bearing shape so that the torsion bar 25 tilts synchronously with the tilt of the movable ram 7.

The lower surfaces of the link members 31a, 31b pivotally supported by the pins 29a, 29b are connected to the tips of adjustment bolts 39a, 39b screwed into the C-shaped frames 9a, 9b via brackets 37a, 37b. By rotating the adjusting bolts 39a, 39b, the vertical positions of the link members 31a, 31b are adjusted.

Also, supporting members 41a, 41 are stretched from the upper surfaces of link members 31a, 31b facing adjustment bolts 39a, 39b, and C-shaped frames 9a, 9b.
A spring 43 whose attachment length can be freely adjusted is interposed between the link members 31a and 31b.
b is always energized toward the adjustment bolts 39a and 39b.

Pressure chamber 4 of the fluid pressure actuated device 13a, 13b
5a, 45b and a pressure fluid supply device 47 for discharging a working pressure fluid such as pressure oil, each pressure passage 49a, 49b has a working fluid supplied into the pressure chambers 45a, 45b via a branch passage 51. A first switching valve 53 is provided to adjust the flow rate.

This first switching valve 53 is a 2-port 2-position switching valve, and the spool 53a of this valve 53 is
are connected to push rods 55a, 55b planted on the upper surfaces of the link members 31a, 31b.

Further, the spool 53a and bushing rods 55a, 55b of the first switching valve 53 are always pressed downward via the spring 57, and therefore the link members 31a, 31b move upward against the elastic force of the spring 57. When this happens, the spool 53a is switched and connected to the tank 59.

The pressure fluid supply device 47 is connected to the drive shaft 61 of the drive motor M, and supplies the working pressure fluid in the tank 63 to the pressure chambers 4 of the fluid pressure actuation devices 13a and 13b.
It is composed of pumps P ₁ and P ₂ that supply the insides of the pumps 5a and 45b. _{A check} valve 65a,
A solenoid valve 69 is provided via 65b and a branch path 67, and this solenoid valve 69 is connected to the tank 63.

The above torsion bar 25 and link member 31
a, 31b, push rods 55a, 55b, and first switching valve 53 constitute a mechanism mainly for adjusting the balance of the movable ram 7.

Next, the positioning adjustment device 73 for controlling the upward stop position of the movable ram 7 will be explained based on FIGS. 1 and 3.

The positioning adjustment device 73 has wedge-shaped position control members 7 on both sides of the movable ram 7 that can be raised and lowered.
5a and 75b are integrally attached.

Above the position control members 75a, 75b, there is an arm member 81, which is referred to as a positioning adjustment mechanism, in a direction perpendicular to the position control members 75a, 75b.
a, 81b are arranged, and these arm members 81a,
One end of 81b is connected to the plate 77 that connects the frames 9a and 9b attached to the machine frame body 3 with the pin 7.
It is rotatably supported via 9a and 79b.

Further, at the other ends of the arm members 81a, 81b, reference rollers 83a, 83b and adjustment rollers 87a, 87b which can be slidably adjusted along the elongated hole 85 are provided.
are provided, and these reference rollers 83a, 83b
The adjustment rollers 87a and 87b are for guiding the tips of the position control members 75a and 75b.

Note that the position control members 75a and 75b attached to the movable ram 7 are not integral, and even when the movable ram 7 is tilted, both the rollers 83a and 8
3b, 87a, 87b so as to be rotatable.

Above the arm members 81a, 81b, feed screws 93a, 93b rotatably supported via a bearing 89 and a hollow connecting portion 91 are arranged in parallel on a plate 77 that connects the frames 9a, 9b. be.

Nut members 95a, 95b are movably screwed into the feed screws 93a, 93b, and the nut members 95a, 95b and the adjustment roller 87
Block member 9 provided integrally with a and 87b
7a and 97b are rotatably connected via pins 99a and 99b and link bars 101a and 101b.

Feed screw 9 connected via the connecting portion 91
3a and 93b, the feed screw 93a located on the right side of FIG. 1 has a right-hand thread, and the feed screw 93b located on the left side has a left-hand thread, and The key member 1 is provided in the connecting portion 91 as shown in FIG.
03.

The feed screw 9 located on the left side in FIG.
3b is formed in a hollow shape with a bottom, and this feed screw 9
As shown in FIG. 3, a knob 109 having a screw 105 at its tip and an integral handle 107 at its rear end is rotatably inserted into the inside of the knob 3b.
The screw 105 at the tip of the knob 109 passes through one end of the feed screw 93b and is screwed into the center of the feed screw 93a located on the right side.

Also, a knob 109 passing through the feed screw 93b
A thrust bearing 111 is installed at the tip of the knob 109 to prevent the knob 109 from moving left and right inside the feed screw 93b.
Nut members 113a and 113b are screwed in through them. Therefore, the knob 109 is connected to the feed screw 93b.
Although it can rotate inside, it is restricted from moving left and right.

Further, the base end portions of the feed screw 93b and the knob 109 penetrate the side wall of the frame 9b fixed to the machine frame body 3 and protrude to the outside, and the feed handle 115 and the knob 109 are provided at the end portions thereof. handle 10
7 are integrally installed.

Next, the fluid pressure actuated devices 13a, 13b,
A pressure passage 49a connecting with the pressure fluid supply device 47,
Second switching valves 119a and 119b for controlling the ascending position of the movable ram 7 are interposed in branch passages 117a and 117b branched from 49b, respectively.

The second switching valves 119a, 119b are
This valve 119 is a port 2 position switching valve.
The spools 121a and 121b of a and 119b are
It is connected to push rods 123a, 123b provided on the tips of the arm members 81a, 81b.

Further, the spools 121a, 121b of the second switching valves 119a, 119b are connected to springs 125a, 1
25b, so that the other ends of the arm members 81a, 81b are pressed downwardly by the spring 1.
When the spools 121a, 121b are moved upward against the elastic force of the spools 25a, 125b, the spools 121a, 121b are switched and connected to the tanks 127a, 127b.

Next, the operation of this embodiment configured as described above will be explained with respect to the case where the movable ram 7 is adjusted and controlled to be balanced and the case where the raised position is controlled.

(A) Balance adjustment action of the movable ram 7 When the movable ram 7 is first raised to press the workpiece W, the foot pedal (not shown),
Alternatively, the solenoid valve 69 is energized by a push button, etc., and the pump is driven by the motor M.
Cut off the branch path 67 from P ₁ and P ₂ to the tank 63,
The working pressure fluid is passed through the pressure passages 49a, 49b to the pressure chambers 4 of the cold body pressure actuating devices 13a, 13b.
5a and 45b.

Then, when the pressure of the working pressure fluid increases beyond the weight of the movable ram 7 and the movable ram 7 rises, the connecting members 21a, 21b are also pulled up via the protruding members 17a, 17b, and the connecting members 21a, 21b and lever member 27a, 2
The torsion bar 25 connected via 7b is
Pins 29a, 29 of link members 31a, 31b
It rotates clockwise in FIG. 2 using b as a fulcrum.

In this way, while the movable ram 7 is rising in parallel, the torsion bar 25 is moved upwards from the link member 2 as the lever members 27a, 27b rise.
Push rods 55a, 55 connect to the spool 53a of the first switching valve 53 by simply rotating around the pins 29a, 29b of 1a, 31b.
It does not push up b.

Next, if the discharge amount of one of the two pumps _{P 1 and P 2 is} different,
Alternatively, the movable ram 7 may
may rise at an incline.

For example, if the load on the movable ram 7 during ascending processing is different and the movable ram 7 is tilted upward to the left in FIG.
It will rise by the difference in slope from the right connecting portion peak 21a.

Then, the torsion bar 25
The torsion bar 25 attempts to rotate around the pin 29 of the link member 1a and the pin 29b of the link member 31b, but as described above, the left side of the torsion bar 25 is pulled upward, so the left link member 31b cannot rotate. It is pulled upwards around the pin 35.

When the left link member 31b is pulled upward, the push rod 55b provided on the upper surface of the link member 31b is also pulled upward,
The spool 53a of the first switching valve 53 is switched to open the communication path to the tank 59, and the rising of the left fluid pressure actuated device 13b is stopped or the speed is reduced.

On the other hand, the fluid pressure actuated device 13a on the right side is
Following the above-mentioned operation, the movable ram 7 continues to rise, and the corrective operation continues until the movable ram 7 becomes parallel.

The above operation is an operation for maintaining and adjusting equilibrium when the movable ram 7 is tilted upward to the left. Even when the movable ram 7 is tilted upward to the right, the above operation is performed in exactly the same way. It is something that can be done.

(B) Function for controlling the ascending position of the movable ram 7 As mentioned above, when the movable ram 7 rises during press working, the wedge-shaped position control provided on both sides of the back surface of the movable ram 7 Members 75a and 75b also rise integrally. Then, the tip portions X ₁ of the position control members 75a and 75b
However, the reference rollers 83a, 83b attached to the arm members 81a, 81b and the adjustment roller 87
a, 87b, and its tip
The inclined surfaces of _X1 are in sliding contact, and the arm members 81a,
The other end of 81b is rotated upward about pins 79a and 79b as fulcrums.

When the other ends of the arm members 81a, 81b rotate upward, at the same time, the push rods 123a, 123b provided on their upper surfaces also move upward, and the push rods 123a, 12
The second switching valves 119a, 119b are connected to the tanks 127a, 127b, respectively, through the spools 121a, 121b connected to the tank 3b.

As a result, the working pressure fluid from the pumps P ₁ and P ₂ is released into the tanks 127a and 127b,
The lifting operation of the fluid pressure actuated devices 13a and 13b is stopped. That is, the movable ram 7 stops while maintaining the pressure that can be increased.

In order to further raise the movable ram 7 in the above state, the feed handle 115 provided on the feed screw 93b is rotated, for example, in the right direction to move the nut members 95a, 95b in the left and right direction. At the same time, the nut members 95a, 95
Adjustment rollers 87a, 87b connected to link bars 101a, 101b and block members 97a, 97b are moved in the left-right direction along elongated hole 85, respectively, to control position control members 75a, 7.
5b's inclined tip X ₁ and the reference roller 83
a, 83b, and the adjustment rollers 87a, 87b are released from the pressure contact state.

Both the rollers 83a, 83b and 87a, 8
7b and the tips of the position control members 75a and 75b.
When the engagement state with X ₁ is released, arm member 8
1a, 81b are second switching valves 119a, 1
The elastic force of springs 125a and 125b that press the spools 121a and 121b of 19b, the arm members 81a and 81b, and the push rod 123
Pins 79a, 79b due to their own weight a, 123b
The second
The switching valves 119a, 119b are switched to block the release of the operating pressure fluid to the tanks 127a, 127b, pushing the fluid pressure operating devices 13a, 13b upward.

If the movable ram 7 and fixed table 5 are not in equilibrium, rotate the handle 107 attached to the knob 109 to move the right feed screw 93a to the key member 10 as shown in FIG.
3 to the left and right, and the reference roller 83a
and the adjustment roller 87a.

By raising or lowering the right side of the movable ram 7, the balance between the fixed table 5 and the movable ram 7 is corrected.

Through the operations described above, it is possible to control the ascending position of the movable ram 7 and to correct the balance of the movable ram 7 with respect to the fixed table 5.

In addition, in the above embodiment, the hydraulic pump P ₁ ,
Two _P2s are used, but the invention is not limited to this.
For example, it is also possible to use one pump and a flow divider valve.

Next, FIG. 4 shows a second embodiment of the positioning adjustment device 73, which, like the above, has the following features:
A feed screw 93 is attached to the plate 77 via a bearing 89.
a, 93b are rotatably supported, and the feed screws 93a, 93b are provided with a nut member 95.
Slide plates 129a and 129b are provided which can be raised and lowered via a and 95b and are movable in the left and right directions.

The slide plates 129a, 129b have one end attached to the nut member 95a, 95b with the pin 131.
a, 131b, and the other end has lifting rollers 133a, 133b, which will be described later.
An inclined surface 135 is formed to make sliding contact with the slide plate 129, and brackets 137a and 137b are provided on the upper surface to guide the back and forth movement of the slide plates 129a and 129b.

Inclined surface 1 of the slide plates 129a, 129b
The above-mentioned elevating rollers 133a, 133b and two guide rollers 139, 141 are provided below and on the other surface of the roller 35.

The lifting rollers 133a, 133b are provided with a shaft 143a, which is integrally implanted on the back side of the movable ram 7.
The shafts 143a and 143b are rotatably supported at the tip of the movable ram 7, and the shafts 143a and 143b move up and down integrally with the movable ram 7 along long holes 145a and 145b formed in the plate 77 of the machine frame body 3. It is.

Therefore, when the movable ram 7 moves up and down, the shaft 14
Lifting roller 1 provided via 3a, 143b
33a, 133b, slide plate 129a,
The inclined surface 135 side of 129b also moves up and down at the same time.

In addition, the two guide rollers 139, 141
The guide plates 129a, 129b are rotatably supported on shafts 147, 149 fixed to the machine frame body 3.

Above the inclined surface 135 side of the slide plates 129a, 129b, second switching valves 119a, 119b for controlling the upward position of the movable ram 7 are provided, similar to the first embodiment described above.

The spools 121a, 121b of the second switching valves 119a, 119b have springs 125a, 12
5b, the constant sliding plates 129a, 129
slide plates 129a and 129b that come into contact with the upper surface of b and move up and down as the movable ram 7 moves up and down;
This switch is operated when the lift is lifted or lowered.

That is, the slide plates 129a, 129b are in contact with the inclined surface 135, and the lifting rollers 133a, 13
3b, the spools 121a, 1 of the second switching valves 119a, 119b
21b is pushed upward against the elastic force of springs 125a and 125b, and the working pressure fluid supplied from pumps P ₁ and P ₂ is discharged into tanks 127a and 127b.

As a result, the fluid pressure actuated device 1
The lifting operation of 3a and 13b is stopped. That is, the movable ram 7 stops while maintaining the pressure that can be increased.

Note that other configurations and operations are completely the same as those of the first embodiment described above, so the same reference numerals are given and detailed explanations are omitted.

As described above, this invention allows the fixed table 5 to be
On the other hand, since the movable ram 7 can be automatically corrected to balance at all times, the working efficiency of press working can be significantly improved, and since the balance of the movable ram 7 can always be maintained, the machining accuracy can also be improved. can.

Furthermore, in addition to automatically correcting the balance of the movable ram 7 described above, the present invention can accurately control the lifting and lowering stop position of the movable ram 7, so that the left and right bending angles in the bending process can be accurately set, and the workpiece material This has the effect of making it possible to perform processing with high precision in accordance with the material, thickness, etc. of the material.

Note that this invention is not limited to the above embodiments,
Other embodiments are also possible, for example a press brake with a movable ram 7 provided above and a press brake that processes this movable ram 7.

[Brief explanation of drawings]

FIG. 1 is a schematic front view of a press brake according to the present invention, FIG. 2 is a partial side view of FIG. 1, and FIG. FIG. 4 is an explanatory diagram showing a second embodiment of the positioning adjustment device. (Explanation of main symbols shown in the drawings), 5
...Fixed table, 7...Movable ram, 13a, 1
3b...Fluid pressure actuation device, 47...Pressure fluid supply device, 49a, 49b...Pressure passage, 53...First switching valve, 21a, 21b...Connection member, 2
5... Torsion bar, 119a, 119b...
Second switching valve, 75a, 75b...position control member.

Claims (1)

[Scope of Claims] 1. Fluid pressure operating devices 13 are provided on both sides of a movable ram 7 provided opposite to the fixed table 5 to raise and lower the movable ram 7 with respect to the fixed table 5.
a, 13b are provided, and the respective pressure passages 4 connect the respective fluid pressure operating devices 13a, 13b provided on both sides of the movable ram 7 and the pressure fluid supply device 47.
9a and 49b are provided with a first switching valve 53, and a connecting member 21 connected to both sides of the movable ram 7.
A torsion bar 25 is provided horizontally via a and 21b, and at both ends of the torsion bar 25,
A press brake characterized in that a link mechanism is provided for switching a first switching valve 53 provided in the pressure passages 49a and 49b. 2. Fluid pressure actuation devices 13 are provided on both sides of the movable ram 7 provided facing the fixed table 5 to raise and lower the movable ram 7 with respect to the fixed table 5.
a, 13b are provided, and the respective pressure passages 4 connect the respective fluid pressure operating devices 13a, 13b provided on both sides of the movable ram 7 and the pressure fluid supply device 47.
9a, 49b are provided with a first switching valve 53 and a second switching valve 119a, 119b, and connecting members 21a, 21b connected to both sides of the movable ram 7.
A torsion bar 25 is installed horizontally through the
A first switching valve 53 is provided at both ends of the torsion bar 25 and interposed in the pressure passages 49a and 49b.
A link mechanism for switching operation is provided, and position control members 75a, 75b are integrally provided on both sides of the movable ram 7.
and a second pressure passage provided in the pressure passages 49a, 49b.
A press brake characterized in that a positioning adjustment mechanism for switching and controlling the second switching valves 119a and 119b is provided between the switching valves 119a and 119b.