JPH0211940Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field This invention relates to an apparatus for releasing a molded product bent by a press bending die from the die.

Conventional technology Generally, when bending a plate-shaped workpiece using a press bending die that includes a first die and a second die, the bent product bites into one of the dies. Therefore, the molded product is released from the mold by a main mold release device provided in the center of the press bending mold. However, it is difficult to eliminate the bite of the bent molded product using only the main mold release device, and if you try to forcefully release the molded product, the bent molded product will become distorted or warped. In addition, a device (for example, a sub-lifter unit) that directly pushes the chamfered portion of the bent product to assist the main mold release device is often used in conjunction with the molded product.

Such a sub-lifter unit is disclosed in, for example, Japanese Utility Model Publication No. 58-6591, and it is
This will be briefly explained based on the diagram.

In the press bending die shown in FIG. 5, a flange 1 is formed on the outer circumference of a plate-shaped workpiece 104 by bringing an upper die 102 close to a lower die 100 whose position is fixed.
06 is bent and formed. A pad 108 is provided on the upper mold 102 so as to be relatively movable within a certain limit in the vertical direction, and is urged downward by a biasing means such as a spring to support a workpiece support surface 110 formed on the lower mold 100. The workpiece 104 is held down between the two. A plurality of sub-lifter units 112 are provided around such a workpiece 104. This includes a cylindrical holder 114 fixed to the lower mold 100, a post 116 fitted into the holder 114 so as to be slidable in the vertical direction, and a biasing direction that causes the post 116 to protrude from the holder 114. and a lift plate 122 fixed to the protruding end of the post 116 together with a guide plate 120 that guides the workpiece 104 to the processing position before bending. When the upper mold 102 descends, the leading pin 124 fixed to it pushes down the lift plate 122, the post 116, etc. against the biasing force of the spring 118, but when the upper mold 102 rises after the bending process is completed, , the lift plate 122 is pushed up according to the urging force of the spring 118, and the contact surface 12 formed at the end of the lift plate 122
6 comes into contact with the end surface of the bent flange 106 and pushes its chamfered portion away from the lower die 100.

Problems that the invention aims to solve Conventional sub-lifter units (mold release devices) require less installation space than press molds that bend and form flanges, etc. on the outer periphery of the workpiece as described above. Since it is relatively easy to secure, there is no particular problem in its incorporation.

However, as shown in FIG. 4, for example, a plate-shaped workpiece W is punched out along a punch line A forming a closed loop, and at the same time, the punched peripheral portion is cut into a similar closed loop shape. When attempting to perform the process along bending line B, since both drawing line A and bending line B form a closed loop and are close to each other, there is a small annular space between them. It is impossible to install a conventional mold release device as shown in FIG. 5 in such a limited space.

Therefore, in the past, since both the drawing line and the bending line form a closed loop and are close to each other as described above, the width between the lines within the second mold is In a punching and bending press device, in which it is difficult to arrange a plurality of mold releasing devices in a narrow annular space, its forming ability is limited to pressing molded products with gentle bending and almost no biting force. In the case of press work that involves bending with a large biting force, it is not possible to perform closed-loop punching and bending at the same time as described above, so punching along punch line A with a punching die is performed in advance to create an opening. After forming the opening, the peripheral edge of the opening is bent along the bending line B using another bending die, and the chamfered portion is bent by the above-mentioned sub-lift unit installed in the space corresponding to the opening. Since it was necessary to push up the material, two processes were required: punching and bending.

Means for Solving the Problems The present invention has been made against the background of the above circumstances, and its gist is to provide a first type and a second type that are moved closer to each other and separate them from each other. By approaching the second die, the workpiece is punched along the closed loop punch line, and at the same time,
In a punching and bending press device that bends the peripheral edge of the opening formed by the punching process along a closed loop bending line, the molded product subjected to the bending process is released from the second mold. A mold release device, comprising: (a) an upper end portion located in an annular space between the closed loop drawing line and the closed loop bending line in the second mold, and parallel to the approaching/separating direction; With multiple ejection pins arranged in the state,
(b) a guide means provided on the second mold for guiding the ejection pin so as to be movable in the longitudinal direction;
(c) a movable base fitted to the ejection pin so as to be movable relative to the ejection pin in the axial direction and supported by a flange portion provided on the ejection pin;
(e) biasing means for biasing the ejection pins toward the first mold; and (e) abutment against the movable base toward the first mold according to the biasing force of the biasing means. a stopper that allows the movable base to move to an ejection position where the tip of the ejection pin engages with the peripheral edge of the bent opening, but prevents the movable base from moving thereafter; and (f) an abutting member provided on the movable base and reciprocating the movable base and the ejection pin together with the first mold by abutting on the first mold. be.

Effects of operation and invention In this way, when the movable base is reciprocated together with the first mold, the annular shape between the closed loop drawing line and the closed loop bending line in the second mold is A plurality of ejection/separation pins whose upper end portions are located in the space and are arranged parallel to the approach/separation direction move towards the first mold to the ejection/separation position, and the upper end portions move toward the first mold to the ejection/separation position. Since it engages with the peripheral edge of the opening bent into the annular space and pushes it out from inside the second mold, even if the bend is sharp or deep and the biting force is large, the bending process can be performed. The molded product can be easily released from the second mold, and the two steps of punching and bending are no longer necessary. In addition, since the multiple ejector pins are each biased by a biasing means, there are cases where the ejector pins do not contact the molded product at the same time during mold release due to variations in dimensions of the bent opening periphery. This eliminates the deformation of the molded product due to local concentration of ejection force.
Furthermore, even if the ejecting pin interferes with the punching and bending part of the first mold for some reason during press adjustment, the ejecting pins are biased by the biasing means, so that the ejecting pin can This prevents the release pin or the punched and bent portion of the first mold from being destroyed.

Embodiment Hereinafter, an embodiment of the present invention will be described in detail based on the drawings.

The press mold shown in FIG. 1 performs punching and bending operations on the plate-shaped workpiece W shown in FIG. This is a punching and bending die that simultaneously performs the punching and bending process, and by bending the periphery of the punched opening, it forms an opening/closing opening (so-called sunroof) in the roof panel of an automobile.

As is clear from FIG. 1, this punching and bending die consists of an upper die 10 as a first die and a lower die 1 as a second die.
It is equipped with 2. The lower die 12 is a fixed die, and has a workpiece support surface 14 for supporting the workpiece W on its upper surface, and an annular portion along the punching line A and the bending line B functions as a punching die and a bending die. It's getting old. That is, an annular groove is formed in the upper part of the lower die 12, and the inner wall surface along the drawing line A serves as a punching die surface 16, and the outer circumference wall surface serves as a bending die surface 18. It is designed to extend to.

On the other hand, the upper mold 10 is movable and is connected to a drive device such as a hydraulic cylinder (not shown), and is raised and lowered thereby to approach and separate from the lower mold 12. This upper mold 10
A pad 20 for pressing the workpiece W against the workpiece support surface 14 of the lower die 12 is incorporated in the pad 20 so as to be relatively movable in the vertical direction. This pad 20 is
A guide pin 22 erected thereon is guided by slidably fitting into a guide bush 24 provided on the first mold 10, and is guided by a spring 26.
is constantly biased in a direction away from the upper mold 10 (downward in this example). The spacing limit of the pads 20 is defined by the contact between the stopper pin 28 provided on the upper mold 10 and the end of the long groove 30 formed on the pad 20.

Further, an annular punch 32 for both punching and bending is fixed to the lower surface of the upper mold 10, and this punch 32 connects the punching die surface 16 and the bending die surface 16 of the lower mold 12.
It is designed to fit between the 8 and 8. Therefore,
The inner edge of this punch 32 and the punching die surface 1
6, and the bending process is performed almost simultaneously using the outer peripheral surface and the bending die surface 18.

As is clear from FIG. 2, inside the lower mold 12,
Two base bars 34, 34 are installed so as to cross the short side of the drawing line A and the bending line B of the workpiece W.
are provided in parallel at a predetermined distance in the horizontal direction, and these base bars 34 function as movable base members. Each base bar 34 is
As is clear from FIG. 1, it is disposed in a plurality of notches 35 formed in the lower mold 12 so as to straddle them, and is movable in the vertical direction, in other words, with respect to the workpiece support surface 14. It is possible to approach and separate from the pad 20 from the opposite side.

Since the structure of both ends of the base bar 34 is the same, only one side will be mainly explained below. On the lower side of the base bar 34, a coil spring 38, which functions as a biasing means in this embodiment, is provided in a pre-compressed state between the lower die 12 and a spring receiving part 36 formed integrally with the lower die 12. There is. Each base bar 34 is constantly biased upwardly, that is, toward the workpiece support surface 14 side, by two springs 38, and has a stopper portion 40 formed integrally with the lower die 12. The upper movement limit is defined by the contact between the base bars 34 and 34, and as a result, the movement stroke of each base bar 34 is S. This movement stroke S approximately corresponds to the bending allowance (flange length) l of the workpiece W. Also,
The total spring force of the four springs 38 is the spring force of the spring 26 between the upper die 10 and the pad 20.
It is considered to be smaller than the spring force of. Furthermore, push-down pins 42 are fixed to both ends of each base bar 34 in a state of upward protrusion. 10 come into indirect contact with each other, each base bar 34 is pushed down within the range of the stroke S described above against the biasing force of the spring 38.

A lifter pin 44 is provided that vertically passes through the base bar 34 and functions as a breakaway pin. One lifter pin 44 is provided on both sides of each base bar 34, and is arranged so as to extend toward the short side of the drawing line A and the bending line B, as shown in FIG. There is. As is clear from FIG. 1, a flange portion 46 is integrally formed on the lower portion of the lifter pin 44 and receives the upper end of the spring 38, so that the flange portion 46 is connected to the base bar 38. is constantly pressed against the lower surface by a coil spring 38. Therefore, the lifter pin 44 and the base bar 34 are always raised and lowered together, but the reason why the lifter pin 44 is not fixed to the base bar 34 is that an excessive load is applied during mold release. The added lifter pins 44 are made to be able to sink against the base bar 34 against the biasing force of the coil spring 38, and due to dimensional variations in the bent opening periphery, etc., multiple lifter pins may be removed during mold release. This is to eliminate deformation of the molded product due to local concentration of ejection force when the parts 44 do not contact the molded product at the same time. Furthermore, during adjustment of the press, for some reason, the lifter pin 44 may become attached to the upper mold 10.
Even if the lifter pins 44 interfere with the punched and bent portion of the upper die 10, the lifter pins 44 or the punched and bent portion of the upper mold 10 are prevented from being destroyed, since the plurality of lifter pins 44 are each urged by the urging means. .

Such a lifter pin 44 is connected to the spring receiving portion 3.
6 in a slidable manner, and is also inserted through a guide bush 48 provided on the stopper portion 40, so that its elevation and descent is guided by holding at two points. That is, between the closed loop drawing line A and the closed loop bending line B in the lower mold 12,
In other words, the lifter pin 44 has its upper end thrusting portion 50 located in an annular space between the punching die surface 16 and the bending die surface 18 and is arranged parallel to the direction of approach and separation of the upper mold 10. It is guided so as to be movable in the longitudinal direction by the spring receiver 36 and guide bush 48 which function as means. The tip end portion of the lifter pin 44 has two parallel vertical surfaces, and this portion serves as a thrusting portion 50 . This push-up action part 50 is slidably fitted from below between the punching die surface 16 and the bending die surface 18 formed on the upper part of the lower die 12, and its tip end is attached to the molded product. This is a portion that comes into contact with the end surface of the bent portion (flange portion) and serves to remove the bite from the bending die surface 18 of the molded product.

Furthermore, as is clear from FIGS. 2 and 3, three lifter pins 52 (only two are shown in the figure) are provided between the lifter pins 44 provided on both end sides of each base bar 34. , are provided at predetermined intervals in the longitudinal direction of the base bar 34. These lifter pins 52 are fixed to the base bar 34 via brackets 54 that project laterally from the base bar 34, respectively, and extend vertically upward toward the long sides of the drawing line A and the bending line B. Both have a push-up action portion 56 similar to the lifter pin 44 on the tip side.
It is equipped with The sub-lifter unit 58 as described above is incorporated into the punching and bending die.

Next, the operation will be explained.

In FIG. 1, the workpiece support surface 14 of the lower die 12
When the workpiece W is placed on the upper mold 10 and the pad 20 are in the raised position, the base bar 34 is in contact with the stopper portion 40 due to the biasing force of the spring 38. And upper mold 10
When the pad and pad 20 are lowered together toward the lower mold 12, the pad 20 comes into contact with the push-down pin 42 and pushes the base bar 34 before the pad 20 presses the workpiece W against the workpiece support surface 14. The lifter pins 44 and 52 are also lowered by a stroke S to the lowered (retracted) position shown in FIG.

After the pad 20 presses the workpiece W against the workpiece support surface 14, the base bar 34 finishes descending, while the upper die 10 further descends while compressing the spring 26, and the punch 32 for both punching and bending Punching die surface 16 and bending die surface 18
By fitting between the two, the punching process and the bending process as described above are performed almost simultaneously, and the flange-shaped part is brought into a state where it bites into the bending die surface 18.

Thereafter, the upper mold 10 is raised and the stopper pin 28 and the upper end of the long groove 30 come into contact with each other, so that in the process of the pad 20 being separated from the workpiece support surface 14, the base bar 34 moves against the stopper 40 according to the biasing force of the spring 38. The lifter pins 44 and 52 are lifted by a stroke S until they come into contact with the workpiece support surface 14 , and the lifter pins 44 and 52 are moved integrally with the base bar 34 .
Lifter pin 4 is pushed up to the vicinity of
The tip surfaces of the molded parts 4 and 52 come into contact with the end faces of the chamfered parts of the molded product, and act to bend it and push it away from the die surface 18. The spring 38 has a spring force sufficient to release the bite in the bent portion of the molded product.

Although not shown at this time, the molded product (W)
Normally, the central part of the molded product is pushed upward by the main mold release device, and the sub-lifter unit 58 has the role of releasing the bite of the bent part of the molded product and assisting the mold release by the main mold release device. Fulfill. However, when sufficient separation molding is performed using the lifter pins 44 and 52, the main mold release device is not necessarily essential.

As described above, in this embodiment, since the lifter pins 44 and 52 are pushed up through the base bar 34, the drawing line A and the bending line B form a closed loop in close proximity to each other. It can be easily installed even in narrow and limited spaces. Therefore, it has become possible to make the press die have a punching and bending die structure that performs punching and bending at the same time.

Furthermore, since the base bar 34 is of a structure that is pushed down not by the upper die 10 but by the pad 20, it is not directly affected by the relative movement stroke (butt stroke) between the pad 20 and the upper die 10. Without being affected, the movement stroke S of the base bar 34 can be set to a small stroke as long as it does not interfere with the punch 32 during machining and can remove the chamfer of the molded product during ejection. This leads to reducing the amount of deflection of the spring 38 and suppressing fluctuations in the spring force.

Although one embodiment of the present invention has been described above, this is literally an example, and the present invention can be implemented in other embodiments.

For example, the two base bars 3 shown in FIG.
4 and 34 may be connected by a connecting member to form an integral framework, which may function as one movable base member. Also,
The number of lifter pins, which are ejection pins, is appropriately determined depending on the shape and length of the bent portion of the molded product.

Furthermore, in the above description, the press mold having an upper mold and a lower mold that are brought closer to each other in the vertical direction is applied, but a press mold having a structure that is brought closer to each other in the horizontal direction can also be applied.

Although not illustrated one by one, it goes without saying that various modifications and improvements may be made based on the knowledge of those skilled in the art as long as they do not depart from the spirit of the present invention.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of the main parts of a punching and bending die equipped with a mold release device, which is an embodiment of the present invention. FIG. 2 is a partial plan view showing the mold release device shown in FIG. 1, and FIG.
FIG. FIG. 4 is a perspective view showing a specific example of a workpiece processed by the punching and bending die shown in FIG. 1, and FIG. 5 is a sectional view of a main part showing a specific example of a conventional mold release device. 10... Upper die (first die), 12... Lower die (second die), 34... Base bar (movable base member), 3
6... Spring receiving part (guiding means), 48... Guide bush (guiding means), 38... Coil spring (biasing means), 40... Stopper part (stopper means), 42... Push-down pin (contact) parts), 44,5
2... Lifter pin (separation pin), 46... Flange portion.

Claims (1)

[Claims for Utility Model Registration] A first die and a second die are provided which are moved closer to each other and separated from each other, and a workpiece is punched along a closed loop punch line by the first die and the second die approaching each other. At the same time, in a punching and bending press device that bends the peripheral edge of the opening formed by the punching along a closed loop bending line, the molded product subjected to the bending is transferred to the second A mold release device for releasing the mold from the mold, wherein the upper end portion is located in an annular space between the closed loop drawing line and the closed loop bending line in the second mold, and the upper end portion is located in the annular space between the closed loop drawing line and the closed loop bending line in the second mold, and a plurality of ejector pins arranged in parallel; a guiding means provided on the second mold for guiding the ejector pins so as to be movable in the longitudinal direction; and a guide means movable relative to the ejector pins in the axial direction. a movable base that is fitted into the ejector pin and supported by a flange fixed to the ejector pin; urging means for respectively urging the ejector pin toward the first mold; A protrusion in which the distal end of the ejection pin of the movable base engages with the peripheral edge of the bent opening by abutting against the movable base that moves toward the first mold according to an urging force. a stopper means that allows movement to the release position but prevents the movable base from moving thereafter; and a stopper means provided on the movable base and abutting against the first mold, thereby stopping the movable base together with the first mold. and a contact member for reciprocating the ejection pin.