JPH0333049B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method of sequentially conveying a workpiece to a plurality of molds for press processing using a feed bar, and in particular, a method for sequentially conveying a workpiece to a plurality of molds for press processing, and in particular, This invention relates to a method that allows workpieces to be transported even if they do not match accurately.

[Background technology and its problems]

When performing multi-step press working with one press machine, as shown in Fig. 5, a plurality of molds 50 each consisting of an upper mold of a slide and a lower mold of a bolster 51 are arranged in the workpiece conveyance direction, and the workpiece is clamped. A feed bar equipped with a device is moved up and down and back and forth in synchronization with the up and down movement of the slide, thereby sequentially conveying and feeding the work to the mold 50. in particular,
After the workpiece pressed by the mold 50 in the previous step is clamped by a workpiece clamping device such as a vacuum cup, the clamping device is raised A, then advanced B, and lowered C. After releasing the clamp of the workpiece clamping device and supplying the workpiece to the mold 50 for the next process, the workpiece clamping device is raised D, then retreated E, and then lowered F, thereby completing one transport cycle. By repeating this transfer cycle, the workpiece is transferred to each mold 50.
The material is sequentially conveyed and pressed into a predetermined shape.

For example, depending on the height of the pressed product and the vertical stroke of the slide, the work clamp device can be lifted,
In other words, the vertical movement distance of the feed bar may be changed. This change is the first mold 50
This is performed with respect to a reference position N determined from the relationship with the supply device that supplies the workpiece to A, and the lift and down amounts of the workpiece clamping device are changed from, for example, L ₁ to L ₂ . According to this, even if the lift or down amount is changed, the reference position N remains unchanged, and the height dimension from the feed bar to the clamping surface of the workpiece clamping device does not change, so there is no need to adjust the height position of the workpiece clamping device. You can get benefits.

On the other hand, since the height when the workpiece is clamped in the mold in the previous process is the same as the height when the workpiece is unclamped in the mold in the next process, the height positions of all molds must be precisely matched. However, the work of adjusting the height position of the mold has become troublesome. The need to make all the molds at the same height occurs in cases other than the case where the lift and down amounts are changed relative to the reference position N.

[Purpose of the invention]

An object of the present invention is to allow workpieces to be transported without any problem even if the height positions of press molds arranged in the workpiece transport direction are misaligned, and to eliminate the need to match these height positions accurately. An object of the present invention is to provide a method for transporting workpieces in multiple steps in a press machine, which facilitates the work of setting molds.

[Means and actions for solving problems]

For this reason, the present invention provides a press machine in which a plurality of molds for pressing a workpiece are arranged in the workpiece conveyance direction, and the workpiece is sequentially conveyed to the molds by moving a feed bar equipped with a workpiece clamping device up and down and back and forth. In the workpiece multi-step conveyance method, the vertical movement distance of the feed bar at the forward position corresponding to the mold of the next process is made smaller than the vertical movement distance of the feed bar at the retreat position corresponding to the mold of the previous process, and A gap is provided between the mold and the work clamping device of the feed bar which has reached the lowered forward position.

By making the vertical movement distance of the feed bar different between the backward position and the forward position in this way, when the feed bar reaches the forward lowering position, even if there is a deviation in the height position of the mold, the work clamping device and the next process can be connected. There is no interference with the mold, so the workpiece can be transferred reliably as specified. In addition, the height position of the workpiece clamping device relative to the feed bar can be adjusted based on the previous process when the workpiece is clamped in the mold.
When changing the lift and down amounts with respect to the reference position, it is possible to eliminate the need for height adjustment of the work clamp device even if the lift and down amounts are changed.

〔Example〕

FIG. 1 shows a press machine 1 in which the conveying method according to the present embodiment is carried out, in which an upper die 3 attached to the lower surface of a slide 2 and a lower die 5 attached to the upper surface of a bolster 4 move the workpiece in the conveying direction. A plurality of molds 6 for press working are arranged. The press machine 1 is provided with a conveying device 7, and a feed bar 9 equipped with a work clamping device 8 using, for example, a vacuum cup or a magnetic suction cup moves up and down and back and forth in synchronization with the up and down movement of the slide 2. As a result, the workpiece supplied to the first mold 6A by a supply device (not shown) is conveyed and supplied sequentially to each mold 6A while being pressed, and the workpiece The workpiece that has reached the mold 6B is taken out from the press machine 1 by a takeout device (not shown).

The conveyance device 7 is based on the application proposed by the applicant in 1983.
-The same equipment as 182050 is used. First, this conveying device 7 will be explained.

The conveyance device 7 consists of a drive unit 10 and two vertical movement units 11, and the drive unit 10 has first and second motors 12 and 13 as drive sources.
are arranged, and these motors 12 and 13 are both
It is a DC servo motor that can control the number of rotations, rotation speed, start timing, etc. Second
As shown in the figure, the first motor 12 has a pulley 14 and a belt 1.
5. A timing belt 19 as an endless running belt connected to a timing pulley 17 via a pulley 16 and stretched between the left and right timing pulleys 17 and 18 reciprocates in the horizontal direction by the forward and reverse rotations of the first motor 12. Run. timing belt 19
A connecting member 21 that is horizontally movable while being guided by a guide rod 20 is connected to the connecting member 21, and the end of the feed bar 9 is connected to this connecting member 21.

This connection is performed by the vertical guide bar 2 of the connecting member 21.
This is done by fitting the end fitting 23 of the feed bar 9 to the connecting member 2 so as to be vertically slidable, so that the feed bar 9 is vertically movable relative to the connecting member 21. The feed bar 9 is held by a feed bar holding member 24 at the vertical movement unit 11, and this holding is performed in a slidable manner, so that the feed bar 9 is movable in the left-right direction, that is, freely movable back and forth.

The second motor 13 is connected to a rotating body 28 via a pulley 25, a belt 26, and a pulley 27, and this rotating body 28 is provided with an eccentric pin 29. The eccentric pin 29 is connected to a lever member 32 provided for each vertical movement unit 11 by connecting rods 30 and 31, and this lever member 32 swings up and down about a shaft 33 by the forward and reverse rotation of the second motor 13. It has an inverted L-shape and consists of a downward arm section 32A and a horizontal arm section 32B. The cooking rods 30 and 31 are connected to the downward arm section 32A, and the feed bar holding member 24 is connected to the horizontal arm section 32A.
It is rotatably attached to 2B.

FIG. 3 is an enlarged view showing the structure of the vertical movement unit 11. A lever member 3 is attached to the vertical movement unit 11.
Balance weight means 34 are provided to support the weight of the feed bar 9 acting on the feed bar 2. This balance weight means 34 includes a cylinder 36 connected to the lever member 32 by a pin 35, and a shaft 3 rotatable to the case 37 of the vertical movement unit 11.
a piston rod 39 connected at 8 and extendable with respect to the cylinder 36, and these cylinders 36,
It consists of a spring 40 compressed and wound around the outer periphery of the piston rod 39. Balance weight means 3
4 follows the vertical swing of the lever member 32 about the shaft 33 by the expansion and contraction of the cylinder 36 and piston rod 39, and supports the weight of the feed bar 9 by the elastic force of the spring 40.

With the above structure, the first motor 12 rotates in the forward direction.
When the timing belt 19 and the connecting member 21 rotate in the opposite direction, the feed bar 9 slides against the feed bar holding member 24 and moves forward and backward. Further, when the second motor 13 rotates forward or backward, the feed bar holding member 24 moves up and down by vertical swinging of the lever member 32 about the shaft 33, and the feed bar 9 rises and falls. At this time, the sliding of the terminal fitting 23 with respect to the guide bar 22 ensures that the feed bar 9 can rise and fall.

Advancement of the feed bar 9 by the first motor 12;
The backward movement stroke and the upward and downward movement strokes of the feed bar 9 by the second motor 13 can be arbitrarily adjusted because the first and second motors 12 and 13 are controllable servo motors as described above.

When setting the lower mold 5 of the mold 6 on the bolster 4 of the press machine 1 shown in FIG. Set based on position N.
The height position of the work clamping device 8 provided on the feed bar 9 from the feed bar 9 is adjusted, and this adjustment is performed on each mold 5 in the previous process when the feed bar 9 is in the lowered position of retreat before starting the press operation. This is done so that each workpiece clamp device 8 can reliably clamp the workpiece. At this time, if there is a difference in height between the lower molds 5 as shown in FIG. 4, the lengths from the feed bar 9 to the respective work clamp devices 8 will vary according to this difference.

The workpieces are transported and supplied to each of the molds 6 by the vertical movement and forward/backward movement of the feed bar 9 by the first motor 12 and the second motor 13, so that the workpiece clamping device 8 is raised A from the lower mold 5 in the previous process. , advance B, descend C to the lower die 5 of the next process, ascend D, retreat E, and descend F. At the same time, the workpiece is clamped in the lower die 5 of the previous process and unclamped with the lower die 5 of the next process. As a result, the workpieces are sequentially fed to the respective molds 6. In this case, the vertical movement distance h 1 of the work clamp device 8 in the mold 6 of the previous process, in other words, the vertical movement distance h ₁ of the feed bar 9 in the retreat position, and the mold 6 of the next process
In other words, the vertical movement distance h2 of the feed bar 9 in the forward position is made different from the vertical movement distance _h2 of the work clamp device 8 in the forward movement position, and _h2 is made smaller than _h1 .
The size of this _h2 is the mold 6 of each next process,
The size is such that a gap S exists between the feed bar 9 and each work clamp device 8 when the feed bar 9 reaches the lowered forward position. according to this,
Even if there is a height difference between the respective molds 6, the workpiece clamping device 8 and the mold 6 for the next process will not interfere with each other, and therefore the sequential conveyance and feeding of the workpieces can be carried out as specified, and the molds can be There is no need to correct the deviation in the height position of the molds 6 to make them match accurately, and the work of setting the molds 6 becomes easier.

Furthermore, by providing the gap S, the workpiece is not pressed against the mold 6 when the workpiece clamping device 8 descends, so accidents such as bending of the workpiece can be prevented, and furthermore, an excessive load is applied to the workpiece clamping device 8. Since this can be prevented, the life of the work clamp device 8 can be extended.

As mentioned above, the height position of the work clamping device 8 with respect to the feed bar 9 is adjusted based on the work clamping time when the feed bar 9 reaches the backward lowering position corresponding to the mold 6 in the previous process. When changing the amount of lift and down of the workpiece with respect to the reference position N, there is no need to adjust the height of the workpiece clamping device 8 from the feed bar 9 because the reference position N remains unchanged.

Vertical movement distance of the feed bar 9 in the backward position
Making the vertical movement distance _h2 of the feed bar 9 in the forward position smaller than _h1 can be carried out regardless of whether or not there is a need to change the amount of lift or down, and also when changing the amount of lift or down. However, this change can also be made to a position other than the reference position N. If the lower mold of the bolster is replaced and reset every time the lift or down amount is changed, this replacement and setting work is improved.

In this embodiment described above, a plurality of molds were installed in one press machine, but each mold was installed in a plurality of press machines arranged in the workpiece conveyance direction, and these molds were installed in a single press machine. The method according to the invention can also be applied when the press machine has feed bars arranged transversely. In addition, in this example, there was only one feed bar, but if the feed bar moves up and down and moves back and forth to feed the work piece sequentially into the mold, two feed bars would be provided and the feed bars would move closer and farther apart. The method according to the present invention can also be applied to a type of device in which a workpiece is clamped and unclamped by performing an operation.

〔Effect of the invention〕

According to the present invention, even if there is a difference in the height positions of the respective molds, the workpiece can be transported without any problem.Therefore, it is not necessary to precisely match the height positions of the molds, and the work of setting the molds is simplified. becomes easier.

[Brief explanation of drawings]

Fig. 1 is an overall front view of the press machine to which the transfer method is applied, Fig. 2 is a perspective view showing the basic structure of the transfer device installed in the press machine, and Fig. 3 is a diagram showing the vertical movement unit of the transfer device. Enlarged front view of section,
FIG. 4 is a diagram showing the conveying method of the present invention, and FIG. 5 is a diagram showing the conventional conveying method. 1...Press machine, 2...Slide, 3...Upper die, 4...Bolster, 5...Lower die, 6...Mold,
7... Transfer device, 8... Work clamp device, 9
... Feed bar, h ₁ ... Vertical movement distance of the feed bar in the backward position, h ₂ ... Vertical movement distance of the feed bar in the forward position, S ... Gap.

Claims (1)

[Claims] 1. A multi-step work transport method for a press machine, in which a plurality of molds for pressing a work are arranged in the work transport direction, and the work is sequentially transported to the mold by moving a feed bar equipped with a work clamp device up and down and back and forth. The vertical movement distance of the feed bar at the forward position corresponding to the mold of the next process is made smaller than the vertical movement distance of the feed bar at the retreat position corresponding to the mold of the previous process, and the mold of the next process. 1. A multi-step work transfer method for a press machine, characterized in that a gap is provided between the feed bar and the work clamp device when the feed bar reaches a lowered forward position.