JP3342727B2 - Bending method and bending apparatus for damping steel sheet - 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 bending a damping steel sheet by sandwiching a resin between two steel sheets.
It is related to the location .

[0002]

2. Description of the Related Art Damping steel sheets formed by sandwiching a resin between two steel sheets have excellent vibration damping and soundproofing effects and can be reduced in weight, so that they are often used in various parts such as electric products, furniture, and automobiles. Used. This damping steel sheet is usually used after being subjected to V-bending by a bending machine such as a press brake having a punch and a die.

By the way, when such a damping steel sheet is subjected to a V-bending process, the lengths of the bent portions of the steel sheet on the front side and the back side of the resin layer are different, so that each of these steel sheets is bent during the bending process. As a result, as shown in FIG. 9, a shape defect, that is, a so-called seagull deformation, occurs in which the portions 52, 52 abutting on both shoulders of the die 51 bend in the opposite direction to the bending direction.

Therefore, conventionally, the following method has been proposed as a method for preventing such seagull deformation. JP-A-2-11225 discloses a processing method in which an elastic block having a V-shaped cross section is inserted on a formed V-groove, and bending is performed between the elastic block and a punch. In Japanese Patent Application Laid-Open No. 2-99222, a coolant gas is blown around a V-bending line of a damping steel sheet to cool the same, thereby lowering the temperature of an intermediate resin layer of the damping steel sheet and increasing its shear adhesive strength. A processing method is disclosed. Japanese Patent Application Laid-Open No. 3-128124 discloses a process in which a bending stress is applied to a bent portion of a vibration-damping steel plate at an initial stage of bending to thereby bend the portion in advance in a yielding state to perform bending. A method is disclosed.

[0005]

However, while the above-described method can achieve the effect of preventing seagull deformation to some extent, there is a problem that this seagull deformation cannot be completely eliminated. In addition, in the above method, depending on the type of the resin sandwiched as the intermediate layer, the cooling effect may not be sufficiently exhibited, or the use of a refrigerant gas may increase the production cost and may require a cooling time. There is a problem that much processing time is required. Further, the above-mentioned method has a problem that the quality of the product may be adversely affected due to a remarkable decrease in the thickness of the bent portion, or a special bending die is required at the time of the processing.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the various problems of the conventional method, and does not require any special equipment, and also reliably prevents seagull deformation without adversely affecting product quality. It is an object of the present invention to provide a method and a device for bending a damped steel sheet that can be prevented.

[0007]

In view of the fact that the place where the seagull-like deformation occurs is located near the boundary between the part where the bending moment occurs inside the material during bending and the part where the bending moment does not occur, the inventors of the present invention consider the following problem. It has been found that it is possible to avoid the occurrence of seagull-like deformation by performing bending while applying a bending moment over the entire region of the above. That is, bending method of the vibration damping steel sheet according to the present invention, there is provided a bending method of the vibration damping steel plate performing V bending with a punch and a die, both edges of (a) the vibration damping steel plate, respectively The shoulders of the die
A preliminary bending step of placing the vibration-damping steel sheet on a portion thereof and bending the vibration-damping steel sheet to a predetermined shallow bending angle less than the final bending angle while imparting a bending moment over the entire surface of the vibration-damping steel sheet including the bending corner; ) After this preliminary bending step, the damping steel sheet is
The method is characterized by comprising a finishing bending step of bending to a final bending angle by bending. Where before
In the preliminary bending step, the movable die in which the groove width of the die can be changed is used.
It is preferably performed using a. By doing this,
Pre-bending process can be performed at each stage of the bending process.
Become.

Further , the above-mentioned bending method is specifically realized.
Because of, the bending apparatus of the vibration damping steel plate according to the present invention, Pas
Bending of damping steel plate with V-bending using punch and die
A processing apparatus, (a) a sliding member that is fixed to the upper surface of the stationary table, (b) freely Daibe move the sliding member on the front-rear direction
Over scan, fixed on (c) the die base, V grooves are formed on the upper surface
A first die, (d) disposed adjacent to the first die, the die base
The fixed die fixed on top and the fixed die
It consists of a movable die slidably provided in the front-rear direction,
A V-groove is formed on the upper surface when the fixed die and the movable die come into contact with each other.
And (e) the die base along the upper surface of the sliding member.
Move in the front-rear direction and place the
Die for positioning the first die or the second die
A driving cylinder.
You.

[0009]

In the present invention, the damping steel sheet is bent to a predetermined shallow bending angle smaller than the final bending angle while giving a bending moment over the entire surface of the plate surface before the usual V-bending. By doing so, since there is no distinction between a portion where a bending moment is generated inside the material during bending and a portion where the bending moment is not generated, the occurrence of seagull-like deformation is avoided.

[0010]

Next, a method for bending a damped steel sheet according to the present invention.
A specific example of the bending apparatus will be described with reference to the drawings.

FIGS. 1 to 4 show a main structure of a press brake applied to a method of bending a damping steel sheet according to an embodiment of the present invention. In the press brake of this embodiment, a sliding member 2 is provided on the upper surface of a fixed table 1, and the upper surface of the sliding member 2 is driven in the front-rear direction (the left-right direction in FIG. 1) by the driving of a die base driving cylinder 3. A slidable die base 4 is supported. On the upper surface of the die base 4, a first die 5 for finish bending is provided at a front portion, and a second die 6 for preliminary bending is provided at a rear portion.
Is provided. The first die 5 is a so-called V die having a V groove 5a formed on the upper surface, and is fixed to the die base 4 by bolts. The second die 6 is disposed adjacent to the first die 5 and has a fixed die 7 bolted to the die base 4 and a movable die 8 disposed opposite to the fixed die 7 so as to be slidable in the front-rear direction. Consists of
Each of the fixed die 7 and the movable die 8 has a shape in which an upper part of an opposing surface is cut obliquely, and a V-groove is formed on the upper surface by the notches 7a and 8a when the dies 7 and 8 come into contact. It has become so.

The movable die 8 is reciprocated by a linear head 9 fixed to the rear end face of the die base 4. That is, when the motor 10 of the linear head 9 is rotated in the forward and reverse directions, the rotational movement is reduced by the gears and converted into linear movement of the rack 11, and the movable die fixed to the end of the rack 11 is moved. 8 is moved in the direction of arrow A in FIG. The movable die 8 is held on the die base 4 by a die clamper 12 embedded in the die base 4. As shown in FIG. 4, the die clamper 12 includes a cylindrical casing 13, a piston 14 slidably provided in the casing 13 in a vertical direction, And a disc spring 16 provided in an upper chamber of the casing 13 defined above the piston 14 and constantly pressing the piston 14 downward. . The casing 13 is provided with a hydraulic passage 17 communicating with a lower chamber defined below the piston 14 and supplying a hydraulic pressure for moving the piston 14 upward against the pressing force of the disc spring 16. Further, a flange portion 15a is provided on an upper portion of the clamp bar 15 for engaging the predetermined portion of the movable die 8 to press the movable die 8 toward the die base 4. As shown in FIG. 2, the die clampers 12 having such a configuration are installed at three locations in the longitudinal direction of the die base 4, and the hydraulic passages 17 of each die clamper 12 are communicated with the hydraulic piping 18 for the movable die clamp. .

With this configuration, when the hydraulic pressure is not supplied to the hydraulic passage 17 of the die clamper 12, the piston 14 is pressed downward by the disc spring 16, so that the flange of the clamp bar 15 is pressed. The movable die 8 is pressed against the die base 4 by the portion 15a, and the movable die 8 is held. In this state, when hydraulic pressure is supplied to the lower chamber of the casing 13 from the movable die clamp hydraulic piping 18 via the hydraulic passage 17, the piston 14 is moved upward against the pressing force of the disc spring 16, and the clamp bar 15 is moved. The pressing of the movable die 8 by the flange portion 15a is released. In this released state, the motor 1 of the linear head 9 is
The movable die 8 is moved as shown by a two-dot chain line in FIG. 1, for example, and the die clamper 12 is actuated again at the moved position to fix the movable die 8 to the die base 4. In FIG. 2, reference numeral 19 denotes a stopper for restricting the die base 4 from moving backward by a predetermined amount or more.

Next, the bending process of the damping steel sheet in the present embodiment using the press brake constructed as described above will be described with reference to FIGS. FIG. 6 (a)
5 (d) show the set state of the workpiece at the time of preliminary bending, and these are the process Nos. They correspond to the bending steps 1, 3, 5, and 7, respectively.

When bending a product having four bending corners b, c, d, and e as shown in FIG. 7 from a plate-like work w, first, the V width k of the movable die 8 is set to the width of the work w. The position of the movable die 8 is set so as to be slightly shorter, that is, both edges of the work w are placed on both shoulders of the second die 6, and in that state, the punch 20 is lowered to bend the corner. The preliminary bending of b is performed (step 1). In the pre-bending step, the positioning of the work w until the punch 20 contacts the work w is performed by positioning means (not shown) such as a backstop device. In addition, the movable die 8 is moved in accordance with a change in the workpiece shape due to the progress of the bending process.
The position of the workpiece w is controlled by the linear head 9 and the die clamper 12 so that both edges of the workpiece w always stay on the shoulders of the second die 6. Thus, in the pre-bending step, the bending process is performed while the bending moment is applied to the entire area of the workpiece w including the bending line. Thereafter, when the preliminary bending is performed until the predetermined bending angle is reached, the punch 20 is once raised and the die base 4 is slid by the driving of the die base driving cylinder 3 so that the first die 5 is positioned below the punch 20. Let me
The work w is placed on the upper surface of the first die 5 and finish bending is performed to the final bending angle (90 °) of the bending corner b (step 2).

When the bending of the corner portion b is completed in this way, the corner portion c is again formed by the second die 6 in the same manner as described above.
(Step 3), and then the first die 5
The finish bending of the corner portion c is performed (step 4).

Next, the front and rear positions of the work w are set in opposite directions, and the preliminary bending (step 5) and the finish bending (step 6) of the corner e are sequentially performed in the same manner as described above, and further, the corner d
The bending process is completed by sequentially performing the preliminary bending (step 7) and the finish bending (step 8).

The control of the bending as described above is performed by an NC control device attached to the press brake. As shown in FIG. 8, the control system in this NC control device is sandwiched between the plate thickness, dimensions, bending angle of the work w to be bent, the plate thickness ratio of the two steel plates, and the middle. Information input unit 21 for inputting work information such as material properties such as resin properties, and a list of conditions under which good bending can be performed such as a pre-bending angle, and conditions such as mold specifications and machine specifications. Condition database unit 22 for storing
Are provided. Then, these work information input units 21
In the preliminary bending condition determination unit 23, the bending angle of the workpiece w and the die 5, based on the input data from the
6 is determined, and in accordance with the conditions determined in this manner, the machine control data calculation unit 24 determines the depth value (drive-in amount) of the punch 20, the BS value (pack stop related data), the die V width, the die used, and the like. Is calculated, and each actuator 26 such as the linear head 9 and the die clamper 12 is controlled by an output signal from the machine control data output unit 25 based on the calculated data.

According to the present embodiment, it is possible to process a work having a complicated shape including bending at a plurality of corners without causing a seagull deformation of the work w.

[0020]

As described above, according to the present invention, pre-bending is performed to a predetermined shallow bending angle smaller than the final bending angle while applying a bending moment over the entire surface of the plate surface, and then ordinary V bending processing is performed. Because it is configured to perform, it does not require special equipment such as a cooling device or back pressure applying device, uses a conventional mold, and reliably prevents seagull deformation without adversely affecting product quality can do.

[Brief description of the drawings]

FIG. 1 is a side view showing a main structure of a press brake applied to a method of bending a damping steel sheet according to an embodiment of the present invention.

FIG. 2 is a plan view of FIG. 1;

FIG. 3 is a view taken in the direction of arrow B in FIG. 1;

FIG. 4 is a sectional view of a die clamp in a press brake according to one embodiment of the present invention.

FIG. 5 is an explanatory view of a bending step in one embodiment of the present invention.

FIG. 6 is an explanatory view of a bending step in one embodiment of the present invention.

FIG. 7 is a diagram showing a product processed by a bending process in one embodiment of the present invention.

FIG. 8 is a block diagram of a control system for controlling bending in one embodiment of the present invention.

FIG. 9 is a diagram illustrating a conventional bending process.

[Explanation of symbols]

 Reference Signs List 4 die base 5 first die 6 second die 7 fixed die 8 movable die 20 punch w work

Claims (3)

(57) [Claims] 1. A method for bending a damping steel sheet, wherein a V-bending process is performed by using a punch and a die, wherein (a) both end edges of the damping steel sheet are both shoulders of the die.
A preliminary bending step of placing the vibration-damping steel sheet on a portion thereof and bending the vibration-damping steel sheet to a predetermined shallow bending angle less than the final bending angle while imparting a bending moment over the entire surface of the vibration-damping steel sheet including the bending corner; ) After this preliminary bending step, the damping steel sheet is
A method for bending a damping steel sheet, comprising a finishing bending step of bending to a final bending angle by bending. Wherein said pre-bending step, bending method of the vibration damping steel sheet according to claim 1, the groove width of the die is effected by using a changeable movable die. 3. A V-bending process using a punch and a die.
A bending apparatus Urn vibration damping steel plate, (a) a sliding member that is fixed to the upper surface of the stationary table, (b) movable Daibe the sliding member on the front-rear direction
Over scan, fixed on (c) the die base, V grooves are formed on the upper surface
A first die, (d) disposed adjacent to the first die, the die base
The fixed die fixed on top and the fixed die
It consists of a movable die slidably provided in the front-rear direction,
A V-groove is formed on the upper surface when the fixed die and the movable die come into contact with each other.
And (e) the die base along the upper surface of the sliding member.
Move in the front-rear direction and place the
Die for positioning the first die or the second die
Of a damping steel plate characterized by having a drive cylinder
Bending equipment.