JPH09192744A - Photoelectronic safety device for bending device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the restrictions caused by the shape of a product or the dimension and to improve the safety by oppositely arranging a light beam emitting and a receiving devices each other on both side faces of a die of a bending press to make the safety device. SOLUTION: A light beam emitting and receiving devices 5, and 6 for a line of light beam 7 are attached in an X direction, that is, on the right and left sides of an upper die (punch) P, and when this light beam 7 is interrupted with a finger, etc., of a worker, the machine is stopped at emergency stop. Further, the safety distance from the punch P and die machining part is made about 8mm, that is, the distance is made so as not to be able to insert the finger of the worker, and at this side before the above, the safety device is released. Further, holders 10, 12 for holding the devices 5, 6 each have a projection part 10a fitted with a recessed part 11a of a holder guide 11 and elastically energized downward slidably in a Z-direction with a pair of compression coil springs 14, so that when the holders 10, 12 are brought into contact with the article W, the holders 10, 12 are drawn upward against the springs 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light beam safety device for a sheet metal work bending apparatus such as a press brake.

[0002]

2. Description of the Related Art In a conventional sheet metal work bending apparatus such as a press brake, as shown in FIGS. 5 (a) and 5 (b), an upper / lower die punch / die for processing is provided, respectively. When a worker's hand enters the dangerous area between the upper and lower tables, it is detected as a safety device to stop the operation of the machine in an emergency. There was a light beam safety device consisting of a receiver.

In FIG. 5, 1 is a press brake and 2 /
Reference numeral 3 indicates the upper / lower table, and 4 indicates the dangerous distance range (for example, about 250 mm) up to the safety distance from the punch / die processing unit. Reference numeral 5/6 is a light beam transmitter / receiver, and reference numeral 7 is a plurality of optical axes.

[0004]

However, as shown for example in FIG. 6 (a), a small cut-and-raised portion 8 is formed in the central portion where an operator's hand may enter the dangerous area 4. When a certain work (product) W ₀ or a work W ₁ having flange portions 9 on the left and right sides is bent, for example, when bending a 10-fold curve, as shown in FIG. Since it blocks the light beam (optical axis) 7, this type of conventional light beam safety device may not be able to function as a safety device due to restrictions on the work shape, which is extremely inconvenient. It was

The present invention has been made in view of the above situation, and a light beam for an emergency stop of a machine of this kind, which is not restricted by the size and shape of the work as shown in the above-mentioned example. The purpose is to provide a safety device.

[0006]

Therefore, in the present invention, the holder members of the light transmitter and the receiver facing each other are arranged on both side surfaces of the mold of the bending apparatus, and further, By configuring each of the holder members so as to be elastically biased downward so as to be slidable in the vertical direction,
It is intended to achieve the above object.

[0007]

According to the present invention as described above, it is possible to obtain a light beam type safety device which is not restricted by the work size / shape or the like.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an embodiment of the present invention will be described in detail based on an example:

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a perspective view of an essential part of an embodiment of a light beam type safety device according to the present invention, FIG. 2 is a front view thereof, FIG.
(B) and (c) show detailed explanatory diagrams of each transmitter section and receiver section.

(Structure) In this embodiment, as shown in FIGS. 1 and 2, one light beam 7 is emitted to the left and right (X direction) of the upper die (punch) P attached to the lower portion of the upper table 2. The device 5 and the receiver 6 are attached, and when the operator's hand or the like cuts off the light beam 7, an emergency stop of the machine is performed, and as shown in FIGS. Are compactly packed and housed in the mold P.

FIG. 3A shows the positions of the transmitter 5 and the receiver 6 in the transmitter holder 10 and the receiver holder 12 for holding the transmitters 5 and the receivers 6 respectively.
For example, the transmitter holder 10 is, as shown in FIGS.
By fitting the complementary protrusions 10a, the pair of compression coil springs 14 are elastically biased (biased) downward so that they can slide up and down in the Z direction.

A receiver holder 1 at the opposite ends of the punch P.
2 and the receiver holder guide 13 are also related to the receiver 5
They are arranged in the same symmetrical shape as on the side, as shown in FIG.
As shown in (c), when the lower end of the transmitter holder 10 or the receiver holder 12 contacts the work W, the spring 14
It is configured so that it can be withdrawn upward against.

(Operation) Next, the operation sequence of the safety device of this embodiment will be described with reference to the flow chart shown in FIG. The press brake 1 of this embodiment has a pair of hydraulic rams 15 as shown in a schematic view in the upper right part of FIG.
It is an example of a model in which the lower table 3 (die side) rises.

In step S1, the press brake 1
When the lower table 3 having the die is lifted after the operation of No. 3 is started, it is detected in step S2 whether or not the light beam 7 shown in FIGS. If it is cut off, an emergency stop is immediately performed in step S3.

On the other hand, if not interrupted, in step S4, the safety device is disabled at a position, for example, 8 mm before the position where the die punch and the die sandwich the work W. The distance 8mm is
It is set as a distance dimension that does not enter the human finger any more, and then, in step S5, the work W blocks the light beam 7, and then the work W is subjected to a predetermined bending work, and after that, In step S6, the lower table 3 is operated so as to descend again, and the process ends.

(Operation) As described above, conventionally,
As shown in FIGS. 6 (a) and 6 (b), since the detection light beam 7 was emitted at a position separated from the mold center line by a safety distance from the mold center line as shown in FIG. In the case of a work W ₀ having a small cut-and-raised part 8 in the center, or a work W ₀ that is too small to put an operator's hand in the dangerous area, or a work W ₁ in which flanges 9 are erected on both left and right sides If various inconveniences have occurred, in the above embodiment, the transmitter 5 and the receiver 6 are attached to the mold,
Since the detection light beam 7 is emitted on the bending line of the work W, there is no flange or cut-and-raising on the bending line in any bending process, and even if a small work is bent, the hand does not block the light beam. Depending on the size and shape of the product,
There will be no restrictions as in the past.

(Other Embodiments) The method of attaching the transmitters and receivers to the mold of the above-described embodiment is not limited to the above-mentioned respective examples, and various modifications are adopted. Of course to get.

[0018]

As described above, according to the present invention, since the transmitter and the receiver are arranged so as to emit the human body detecting light beam on the bending line of the mold of the bending apparatus, the size of the workpiece / It is now possible to prevent the risk of pinching hands between molds without being restricted by the shape or the like.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part of an embodiment.

FIG. 2 is a front view of a main part of the embodiment.

FIG. 3 is a detailed explanatory diagram of each transmitter unit and receiver unit.

FIG. 4 is an operation sequence flowchart of the embodiment.

FIG. 5: Light beam safety device of a conventional example

FIG. 6 Example of conventional constraint work

[Explanation of symbols]

1 Press Brake 2/3 Upper / Lower Table 4 Hazardous Area 5 Transmitter 6 Receiver 7 Ray 8 Cutting and Raising 9 Flange 10 Transmitter Holder 10a Convex 11 Transmitter Holder Guide 11a Recess 12 Receiver Holder 13 Receiver Holder Guide 14 Spring 15 Hydraulic ram W ₀ , W ₁ , W Work P Punch (die)

Claims (2)

[Claims] 1. A light beam safety device for a bending machine, wherein holder members for a light beam transmitter and a receiver, which face each other, are provided on both sides of a mold of the bending machine. 2. The light beam safety device for a bending apparatus according to claim 1, wherein each of the holder members is elastically biased downward so as to be slidable in the vertical direction.