JPS6358647B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for holding and following the front end of a sheet metal against the springing up of the sheet metal during bending work of the sheet metal using a press brake, and more specifically, This invention relates to a method and apparatus for following and holding a sheet metal, which is adapted to box bending of the edge of a sheet metal using a press brake.

The term "box bending" mentioned above is generally difficult to understand, but when making a box by bending board materials, the side walls usually rise up from the bottom plate at right angles.
At the required height, it is often bent inward once again at right angles so that the leading edge of the plate is parallel to the bottom plate. This is because the board material is prepared by shearing, so there are burrs on the edges that can hurt your hands, and also because the product has strength and appearance requirements.

The expression "box bending" used in this specification refers to the subsequent bending method of the overlapping bending process, which is parallel to the bottom of the box after the bending process and wraps around the upper die of the press brake, as described above. shall be taken as a thing.

There is no conventionally known bending plate tracking device for press brakes that can handle box bending. In other words, like the bending after the box bending described above,
It was not possible to handle bending that would wrap around the upper mold.

Furthermore, the following movement was performed by sensing when the plate material floated away from the support table and rapidly chasing it. This method is performed near the edge of the table closest to the bending center, but it takes advantage of the undesirable phenomenon of the board bending and lifting near the sensor, so depending on the type of board, dents may remain in the product. It was unsatisfactory as there were bumps and scratches.

The present invention is an invention that improves these points,
A detailed explanation will be given below based on the drawings. This explanation describes a press brake in which the lower die approaches and moves away from a fixed upper die to perform bending work, but a press brake in which the upper die approaches and moves away from a fixed lower die is also applicable. It is clear that the technology disclosed can also be used for brakes.

FIG. 1 is a side view of the apparatus of the present invention installed a certain distance in front of a press brake.

2 is a plan view of the same, and FIG. 3 is a front view of the same, a part of which shows the - cross section of FIG. 1.

Reference numeral 1 denotes a follow-up device which is placed in front of the press brake and has two wheels 9 on both ends of one rear wheel 7 on two rails 5 fixed to a base plate 3. , the front wheels have separate left and right yoke brackets 1
Each of the machines 1 and 1 is equipped with wheels 9, and a machine stand 13 made of sections is placed movably on rails.
In front of the board 3, as shown in FIG. 1, a post 15 made of a combination of sections is fixed vertically.
By rotating the handle 17, the nut member 27 provided at the front central lower end of the machine base 13 as shown in FIG. 3 moves back and forth via the sprocket 19, chain 21, sprocket 23, and screw rod 25. The position of the entire machine base 13 in relation to the press brake can be changed arbitrarily.

There are two frames on the machine stand 13, the lower frame is named the lifting frame 29, and the frame positioned above the lifting frame 29 is named the tilting frame 31. Both frames shown in FIGS. 1 and 3 are each stopped in a horizontal position at the lowest position by height-adjustable stoppers (not shown).

The lifting frame 29 can be adjusted and fixed at an appropriate height position, and is made by overlapping one thick plate 33 of the same shape and size and two thin plates 35 half the thickness of the thick plate 33, and mutually interchanging them in the center. It is placed on the machine base 13 by a pair of left and right cross link mechanisms 37 rotatably connected to the machine base 13,
The central connecting portions of the left and right cross link mechanisms 37 form one central shaft 39. In addition, the rear end of the cross link mechanism is connected to the lifting frame 2 as shown in FIG.
9 and the rear upper end protrusion 43 of the machine base 13, and the front end is connected to the elevating frame base 29 and the guide brackets 45, 49 in front of the machine base 13, respectively. It is movable back and forth through a bearing 49. Note that the distance between the upper and lower guide brackets is slightly larger than the outer diameter of the bearing, so that the outer ring of the bearing does not touch the upper and lower surfaces of the guide bracket at the same time.

An elevating drive mechanism 51 is provided at the left-right center of the elevating frame and the machine base, at a position slightly shifted forward from the center in the front-rear direction. The elevating drive mechanism 51 has the same structure as the tilting drive mechanism 53 described later, and its screw head 55 is pivoted to the elevating frame base, and the nut member frame 57 is pivoted to the machine base 13 via the frame. There is.

Therefore, when the nut member is rotated within the frame, the screw head expands and contracts, and the lifting frame 29 rises and falls while maintaining a horizontal position.
It can be fixed by locking the threaded portion.

As seen in FIG. 3, the tilting frame 29 has a link mechanism collectively referred to as a double pantograph mechanism 59 near the rear ends of both the left and right sides of the lifting frame and the tilting frame, which do not interfere with the cross link mechanism 37. We are prepared. As shown in detail in FIG. 5, the 2-axis link 61 and the 3-axis link 63 are parallel and sandwich the 3-axis link 65 from both sides, and the 2-axis link 67 is parallel to the 3-axis link 63.
The three-axis link 63, which is parallel to the axis link 65, also sandwiches the two-axis link 67 from both sides. Also, the center distances of these axes are all made to be the same size, and the rear end axes of the four links (the left end axis in Figure 5), that is, 2
The shaft 69 of the shaft link 61 and the shaft 7 of the three-shaft link 63
1, the shaft 73 of the three-axis link 65 is attached to the lifting frame 29.
The shafts 75 of the two-shaft links 67 are both rotatably mounted on the inclined frame 31, and the remaining shafts are rotatably connected between the intersecting links as shown in FIG. are doing.

With the double pantograph mechanism 59 configured as described above, a straight line connecting the center of the shaft 69 and the center of the shaft 71, and a straight line connecting the center of the shaft 73 and the center of the shaft 75 are such that the elevating frame is immovable. If so, no matter what angle the tilt frame is tilted, they will intersect at one point in the air as shown in FIG.

Therefore, as described above, the front and back positions of the machine base 13 are determined by operating the handle 17 in FIG. If the above-mentioned point in the air is chosen as the front shoulder 77 of the V-groove of the lower mold while the frame is stopped at the lowest position, no matter what angle of inclination the tilt frame changes, the shaft 73 The lower surface of the sheet metal on the material pedestal fixed on the slanted frame is in front of the V-groove of the lower mold, with the straight line connecting the core of the shaft 75 and the center of the shaft 75 keeping an angle α with the horizontal line shown in FIG. It will pass through shoulder 77.

Next, the tilting drive mechanism 53 for tilting the tilting frame base will be explained. As best shown in FIG. The frame body 81 is pivoted between the left and right brackets 87 provided above and protruding from the bottom of the elevating frame 85, and the lower part thereof is swingable in the front and back direction. The screw head 89 is attached to the shaft 90 on the inclined frame base.
The double pantograph mechanism 59 is used to tilt the inclined frame base and raise the pivoted part. The servo motor 83 includes a resolver 91 and rotates the servo motor in forward and reverse directions according to commands from a numerical control mechanism, and rotates the nut member in the screw nut member frame 85 via a gear 93, a timing belt 95, and a gear 97. do. This causes the screw 99 to move up and down without rotating itself.

Furthermore, this device includes a swing assist lever 10 that assists in swinging the lower part of the frame 81 of the tilt drive mechanism shown in FIG.
1 is provided. This lever has screw head 8
The tilt drive mechanism 5 is coaxially attached to the tilt frame base with
The frame 81 of No. 3 is in contact on one side with a grooved pulley 103 rotatably provided on the right shaft which is pivoted on the left and right brackets 87 provided protruding from the bottom of the lifting frame 29, and the frame In this embodiment, the grooved pulley 105 of the same shape and size, which is provided near the lower end of the frame body on the center line in the longitudinal direction, is in contact with the grooved pulley 105 on the opposite side.
Even if the tilting frame base is tilted, the lower part of the frame body 81 is forced to swing so that the three axes are always on a straight line, so that the swinging is performed so that no bending moment is applied to the screw 99. It is a subsidiary, and the first
As shown in the figure, when the frame 81 returns to the vertical position, it depends on the rotational moment due to the frame's own weight. However, the shape of this swing auxiliary lever is not limited to this example, and even if the lever is an elongated hole that sandwiches the pulley on both sides, the width of the elongated hole should be made slightly wider so that the lever does not come into close contact with both sides of the pulley. Since this is sufficient, it is included in the same technical range as the illustrated example, and in this case, it is guaranteed that the centers of the three axes are located on one straight line even in the return direction.

On the top surface of the inclined frame, there are many ball buttons 1.
07 is fixed, and in this embodiment, three sets of sheet metal adsorption devices 111, detailed in FIGS. 6A and 6B, are provided between the material receiver and the inclined frame. It is being The suction device 111 consists of a left and right guide 113, a sliding plate 115, a fluid pressure cylinder 117, and a circular suction part 119. The circular suction part is like a magnet or a vacuum cup and is configured to rotate horizontally. The material holder is provided with an elongated hole or a semi-elongated hole in the front-rear direction, and when the fluid pressure cylinder 117 is actuated to extend the piston rod, the adsorbed plate material remains adsorbed. , it can be moved diagonally backward by sliding lightly on the ball bush. Note that reference numeral 121 is a leaf spring, which is positioned slightly lower than the pass line of the material when the suction part 119 does not perform suction, but when it is suctioned, it stores downward force and causes the material to come into contact with the ball bushing. It works like this.

What is shown on the left end of FIG. 1 is the lower apron 123 in this embodiment of the press brake, and the rack 12
5, a pinion 127, and a pulse transmitter 129, which transmits the movement length of the lower mold 77 toward and away from the fixed upper mold as a precise pulse to a computer.

Since the present invention is constructed as described above, its operation will be explained below with reference to FIG.

First, before performing box bending, the upper die 1 to be used
31 and decide on the lower mold. At this point, the height of the tip of the upper mold that does not move is determined, the height of the upper surface of the plate placed on the lower mold, and the longitudinal position and height of the front shoulder of the V groove are also determined.

If you use a lower die in which the front shoulder of the V-groove is shifted forward by d as shown in Figure 5, operate the handle 17 to move the machine forward by d.
When the height of the upper surface of the lower mold changes, the pass line of the material pedestal also moves up and down accordingly, and as shown in Figure 5, when the elevating frame and the tilting frame occupy the lowest positions, , match the V-groove front shoulder position when the lower die is at its lowest position. FIG. 7-1 shows this state.

Next, as shown in Figure 7-2, the lower die moves up in a horizontal position until the lower end touches the top surface of the plate material, and the lower die moves up according to the data that has already been input.
The pulse transmitter 129 continues to feed back the lifting distance to the control device, and this pulse causes the resolver of the lifting drive mechanism 51, the servo motor screw, etc. to move the lifting frame to a horizontal position by the same distance as the lower die. It rises at ゝ.

Figure 7-3 shows the state in which the box bending at the required angle has been completed, and the follow-up movement from Figures 7-2 to 7-3 is the lower mold approaching the upper mold, and the tilted frame being moved closer to the upper mold. Requires exclusively tilting movements. In this case, the material springs up centering on the front shoulder line of the V-groove, and the inclined frame also springs up centering on the same point, so the extension dimension of the ball screw for the inclined frame is sometimes determined from the rising pulse of the lower die. This is calculated moment by moment and given as a signal from the control device, allowing the tilting frame to accurately follow the rise of the board without being too early or too late.

Figure 7-4 shows a state in which only the lower die has returned to the starting position. This operation is easy because it is equipped with an automatic control device. However, the adsorption device 111
The other equipment, including the , remains stationary.

Figure 7-5 The fluid pressure cylinder 117 of the adsorption device is operated to lower the adsorption section 119 downward. As a result, the portion where the tip of the box bend wraps around the upper mold is separated from the upper mold.

Figure 7-6 By operating only the lifting drive mechanism 51,
Lower the entire product vertically to mid-height.

Figure 7-7 Now, only the tilting drive mechanism 53 is operated to bring the product into a horizontal state.

Figure 7-8 Next, only the lifting drive mechanism 51 is operated to lower the product to the starting height. By returning the suction device and eliminating the suction force of the suction part, the product can be easily removed forward.

As described above, according to the device of the present invention, box bending work that wraps around the upper mold, which could not be done with conventional automatic control, can be automatically controlled, and the work is efficient and safe without causing any damage to the product. It is effective.

Also, in the above embodiment, a press brake was described in which the lower die approaches and moves away from the fixed upper die, but when the opposite upper die approaches and moves away from the fixed lower die,
Regarding the release method press brake, once the box bending is completed, the product is raised together with the upper mold with both ends of the plate still up, and the suction device is moved diagonally. It is only necessary to slide it down to separate the tip from the upper die and then lower it.Although the order of operations shown in FIG. 7 is different, this can be easily carried out.

[Brief explanation of the drawing]

FIG. 1 is a side view, partially shown in cross section, of this apparatus installed in front of a press brake in which a lower die approaches and moves away from a fixed upper die.
FIG. 2 is a plan view of only the present device, with the lower half shown with the material holder removed. Figure 3 is the − of Figure 1.
FIG. 2 is a front view including a cross section. FIG. 4 is a view taken in the direction of the arrow in FIG. 3, and shows the swing assist lever. Figure 5 shows
It is an explanatory view showing a function of a double pantograph mechanism. 6A and 6B are explanatory diagrams of the adsorption device, where A is a plan view and B is a side view. 7. FIGS. 1 to 8 are process explanatory diagrams illustrating the processing method of the present invention. Explanation of symbols representing main parts of the drawings, 1...Following device, 29...Elevating frame base, 31...Inclining frame base, 3
7...Cross link mechanism, 51...Elevating drive mechanism, 53...Inclination drive mechanism, 59...Double pantograph mechanism, 77...Front shoulder of lower V groove, 79...
... Material holder, 81 ... Frame, 83 ... Servo motor, 91 ... Resolver, 101 ... Swing auxiliary lever, 111 ... Adsorption device, 119 ... Adsorption part, 1
29...Pulse transmitter, 131...Upper mold, 133
...lower mold.

Claims (1)

[Claims] 1 (a) While the upper die and the lower die are approaching, the lower surface of the plate material is
During the process of holding the plate at the same level as the front shoulder line of the lower die V groove, and (b) from the time the lower end of the upper die contacts the top surface of the plate until the end of box bending, the tilting frame is exclusively driven to hold the plate. (c) After the box bending is completed, the tip of the plate wraps around and contacts the upper die, and the upper die and the lower die are placed in the same position as before the start, with the front and back sides still springing up. (d) moving the suction device diagonally backward to separate the box bending tip from the upper mold; (e) returning the plate material to a horizontal position by exclusively driving the tilted frame. (f) The process of exclusively driving the lifting frame base to lower the plate material to the same level as the front shoulder line of the lower V-groove is carried out by guiding the movement pulse of the moving mold to the control device via a computer. Accordingly, a method for supporting and tracking plate materials in a press brake automatically performs box bending work of plate materials in a sequential order. 2. There is a base that can adjust the position in the front and back direction on the rail fixed on the board, and on the base, a lifting drive mechanism equipped with a cross link mechanism, a pulse motor, and a resolver, An elevating frame that moves vertically up and down while maintaining a horizontal position, and on the elevating frame,
A tilting frame is equipped with a tilting frame that flips up and lowers backwards around the V-groove front shoulder line of the lower die using a double pantograph mechanism, a pulse motor, and a tilting drive mechanism equipped with a resolver. A plate material support and follow-up device for a press brake, which is equipped with a suction device that can move in the front and back direction parallel to the top surface of the material holder between the inclined frame and a moving pulse generator that moves up and down the press brake. .