JP2002126899A - Beam type safety device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a workman to carry out safety and efficient work by making a guard board for preventing invasion from the lower side of the workman's hand and arm an optimal length in moving the safety distance caused by change, etc., of the die size of a press. SOLUTION: Downward optical axes provided with a plurality of optical axes creating safety space, and arranged at the position for keeping the safety distance from a dangerous area, a guard member 17 for preventing an invading body from the lower side is provided, and the guard member is fixed at the overlapping position above an L-shaped guard member 34 fixed to the press.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a beam type safety device for a press machine.

[0002]

2. Description of the Related Art Conventionally, in an industrial machine such as a press machine, a light beam type safety device has been installed between a machine and an operator to ensure the safety of the operator. For example, FIG. 7 is a diagram showing an example of such a light beam type safety device. As shown in the figure, the light beam type safety device is provided between a press machine and an operator, and is composed of an issuing unit 71, a light receiving unit 72, and a control unit 73. Then, according to the control signal output from the control unit 73, the light emitting element 1-1 at the top of the issuing unit 71
.. 1-n sequentially emit light, and the light receiving section 7
2-n light receiving elements 2-1, 2-2, 2-3,... 2-n
Receives the corresponding light.

When light from any of the light-emitting elements cannot be received by the corresponding light-receiving element, that is, when light is blocked by a part of the body of an operator, a part, a material, or the like, driving of the press machine Even if the signal is input, the driving of the press machine is stopped. Further, even when the press machine is being driven, if the light emission from the light emitting element is interrupted, the drive of the press machine is immediately stopped.

Further, in such a conventional light beam safety device for a press machine, for example, when the upper mold is driven to descend, if even one optical axis is in a light-shielded state, the drive of the press machine is stopped. And today, from the aspect of ensuring safety,
An optical axis of layers or more is provided between the operator and the press machine, and control is performed to drive the press machine when all the optical axes pass through. That is, a PSDI (Presence Sensing Device Initiation) function that outputs a signal for operating the upper die of the press machine by one stroke from the top dead center position when the worker sets the work material in the mold and returns his / her arm. Is adopted.

Therefore, in the press machine using the PSDI function as compared with the conventional light beam type safety device, sufficient consideration must be given to safety. In other words, the beam-type safety device must make an accurate judgment and ensure the safety of the worker. For this reason, guard plates are provided between the operator and the press machine at the sides and below so that the light beam safety device does not make an erroneous determination. This prevents an operator's hand or the like from entering from a place where there is no optical axis, and copes with a malfunction of the press machine.

[0006] Incidentally, there is a dangerous area between the operator and the press machine. This indicates how far from the position immediately before the mold of the press machine is dangerous or how far from the position is safe. The danger area or the safety distance is set for each press machine, and is obtained by a predetermined calculation formula.

[0007] The length of the guard plate for preventing the above-mentioned beam type safety device from entering the press machine from below must be equal to the length of the safety distance. That is, there must be no gap under the safety device between the press machine and the operator.

[0008]

However, as described above, the position of the safety distance changes depending on the size of the mold and the type of the press machine. For example, if the mold is changed to a smaller one, the safe distance moves toward the press machine. At this time, the beam-type safety device is moved in accordance with the safety distance. However, since the guard plate is usually fixed to the press machine side, the guard plate is extraly protruded by an amount corresponding to the movement of the beam-type safety device. Therefore, the worker must extend his arms as much as possible every time the material is placed on the mold, resulting in inefficient work. Also, when the mold is changed to a large one, it is very dangerous that the guard plate is not long enough and a gap is formed below the press machine.

In view of the above problems, the present invention makes it possible to extend and contract the length of the guard plate while maintaining the strength even when the safe distance changes depending on the size of the mold and the type of the press machine.
It is an object of the present invention to provide a light beam type safety device that allows an operator to work safely and efficiently.

[0010]

According to the present invention, there is provided a light beam type safety device for a press machine, comprising: a plurality of optical axes for creating a safe space; This can be achieved by providing a light beam type safety device characterized in that a guard member for preventing intrusion from below is provided below the optical axis disposed at a position where the safety distance S is maintained from the area.

Here, the dangerous area refers to an area on the front surface of the die when the upper die (die) of the press machine reaches the lower die (die), and a position immediately before the die is not related to the dangerous area. Is the safe distance S. Further, the guard member is configured to have such a size that no gap is left below the press machine and the worker when the guard member is mounted on the L-shaped guard member of the press machine.

With such a configuration, the guard member can move together with the safety distance S.
The guard plate does not protrude excessively to the operator side, and the length of the guard plate is not short, so that there is no gap below the press machine. According to a second aspect of the present invention, in the light beam type safety device according to the first aspect, the guard member is fixed at a position overlapping an L-shaped guard member fixed to the press machine. I do.

With this configuration, the work can be performed without leaving a gap below. According to a third aspect of the present invention, in the light beam type safety device according to the second aspect,
The guard member is fixed to a first moving frame that moves in the front-rear direction with respect to the press machine, and slides on a surface of the L-shaped guard member.

Here, when the guard member is moved back and forth, the size of the guard member and the L-shaped guard member is adjusted so that there is no gap below the safety space even if the guard member is moved to the front or the back. Set. With this configuration, the length of the guard plate can be easily adjusted without leaving a gap below.

According to a fourth aspect of the present invention, in the light beam type safety device according to the third aspect, when the guard member and the L-shaped guard member overlap each other, the entire length is always equal to the safety distance S. It is characterized by being equal in length. With this configuration, the worker can work safely and efficiently at the optimum working position.

According to a fifth aspect of the present invention, in the light beam type safety device according to the fourth aspect, the safety distance S is a distance from a position immediately before a die of the press machine, and is calculated by a predetermined calculation formula. It is characterized by what is required. With this configuration, the operator can perform the press work at a safe and efficient distance.

According to a sixth aspect of the present invention, in the light beam type safety device according to the fifth aspect, of the plurality of optical axes, an optical axis disposed at an uppermost portion and a lowermost portion of the safety space is the first type.
It is characterized by being disposed on a second moving frame movable vertically with respect to the moving frame.

With this configuration, an accurate safety space can be set even if the size of the mold used changes. According to a seventh aspect of the present invention, in the light beam type safety device according to the sixth aspect, the surface of the L-shaped guard member is a bolster upper surface.

With this configuration, the guard member can be moved smoothly without leaving a gap below the operator and the press machine.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a cross section of a light beam type safety device (hereinafter, simply referred to as a safety device) 11 of the present embodiment. Although the safety device 11 in FIG. 1 is installed on both sides of a press machine (not shown), only one is shown for simplicity of explanation. Also, in the same figure, the arrow F direction is the front direction of the press machine, and the arrow B direction is the rear direction of the press machine.

In FIG. 1, the safety device 11
Optical axis a to optical axis d, and of these four optical axes, optical axis b
A fixed frame 12 for fixing the optical axis d, four pipes 13 to 16 for supporting the fixed frame 12, and a guard plate 17 (iron plate) for preventing entry from below. As will be described later, the pipes 13 to 16 allow the fixed frame to be moved in the up-down direction or the front-back direction with respect to the press machine. That is, the moving frame includes two moving frames, a moving frame that moves in the up-down direction and a moving frame that moves the moving frame further in the front-rear direction.

The safety device 11 is provided with a side guard 18 on the outside to prevent intrusion from the side. Each of the optical axes a to d has a large number of optical axes formed at regular intervals. In addition, the light emitting element of the optical axis is
For example, it can be constituted by an LED, a laser or the like, and the light receiving element is constituted by a phototransistor, a photodiode or the like.

In the above-described direction of arrow B, a worker (not shown) is located, and faces the press machine with the safety device 11 interposed therebetween. Here, the operator reaches the hand on the lower mold (not shown) through the safety device 11 with the material in order to place the material on the upper mold (not shown) of the press machine. At this time, since the optical axis is blocked, the press machine is not driven. That is, the optical axis a is interrupted, and then the optical axis b or the optical axis c is interrupted. Further, the material is placed on the lower mold (die) while blocking the optical axis d. Then, when the arm is returned in this state, all the three optical axes are in a light transmitting state, and the PSDI
It starts up and drives the press machine one step.

First, the configuration of the positions of the optical axes a to d in FIG. Distance A between optical axis a and optical axis d
Is set to the safety distance S. Further, the optical axis d is arranged at a position immediately before the mold. And this safety distance S
Is defined according to the following formula, the operator can perform the press work closer to the press machine,
Work efficiency can be improved.

Safety distance S = Sudden stop time of press machine (m
s) × safety factor 1.6 (mm) Here, the sudden stop time of the press machine is a time indicating how long the press machine stops after receiving a stop signal during driving of the upper die. , Safety factor 1.6 is a multiplier used when obtaining the safety distance S. The setting of the safety distance S is performed for each press machine, and the present embodiment also complies with the above-described rules.

Next, the distance B between the optical axis b and the optical axis c is larger than the thickness of the arm of the operator and smaller than the height of the mold when the upper mold of the press machine is lowered most. That is, the distance must be such that the optical axis is not blocked when the upper die is at the position of the bottom dead center while ensuring the safety of the hands and arms. By setting the distance B in this manner, the safety device 11 can transmit a reliable operation signal to the press machine. Note that a mold smaller than the normal distance B cannot be used, but any mold that can adjust the positions of the optical axis b and the optical axis c within a range that does not impair safety can be used.

Next, the fixed frame 12 and the pipe 1 shown in FIG.
The configuration of the pipes 3 to 16 will be described. First, the optical axis b
The three optical axes d to d are arranged on the fixed frame 12. At this time, the optical axis b is disposed in parallel to a position where the optical axis b is not in contact even when the mold (not shown) reaches the lowermost position. Further, the optical axis c is also disposed in parallel with a position where the optical axis c does not contact the lower mold. Further, the optical axis d is disposed immediately before the upper mold and the lower mold as described above. The distance between the optical axis b and the optical axis c is set to the distance B as described above.

The fixed frame 12 can be moved up and down by being fixed to the pipes 13 and 14, and the optical axis can be adjusted according to the shape of the mold. here,
FIG. 2 is a diagram showing an AA cross section of FIG. As shown in the figure, four pipe penetrations 21 are attached to the fixed frame 12 (the two pipe penetrations 21 on the pipe b side are not shown), and the pipes 13 and 14 are attached to the pipe penetrations 21. Can penetrate, and can slide vertically. Note that each of the pipes is connected to the pipe penetration portion 21.
When fixing with pipes, the inside diameter of the pipe penetration portion 21 may be processed to be slightly smaller than the respective pipes and fixed, or may be fixed with screws or the like.

As shown in FIGS. 1 and 2, the optical axis a is fixed to the pipe 13 by bolting, and a guard plate 17 is provided on the pipe 13 by welding or bolting. Etc. are fixed. In addition, various methods such as press-fitting and sticking other than fixing by welding or bolting are conceivable.

At both ends of the pipes 13 and 14, pipe penetration portions 22 are provided, respectively, and the pipes 15 and 16 penetrate the pipe penetration portions 22 in the same manner by the above-described fixing method and the like. Fixed. Accordingly, since the optical axis a to the optical axis d can be moved in the front-rear direction with respect to the press machine in an integrated configuration,
The optical axis a can be easily moved to a position where the safety distance S is secured.

The pipes 15 and 16 are fixed to a side guard 18 fixed to a press machine (not shown) by bolting or the like. The side guard 18 is formed with a large number of holes 19 having a predetermined size to ensure airflow. Next, the guard plate fixed to the pipe 13 will be described in detail. FIG. 3 is a front view of the safety device 11 including the press machine. In the figure,
The press machine 31 includes a slide 32 for attaching an upper mold (mold) (not shown) and a bolster 33 for attaching a lower mold (mold).
The bolster 33 has an L-shaped guard plate 34
Are fixed by bolting or the like. The material of the L-shaped guard plate 34 is an iron plate or the like, similarly to the guard plate 17. Further, an operation panel 35 and a control panel 36 are attached to the press machine 31. An operation push button board 37 is provided in front of the press machine.

The guard plate 17 is fixed to the pipes 13 and 13 'at such a position as to ride on the upper surface of the bolster 33. At this time, the distance C is the length from the pipe 13 to the pipe 13 'in the safety device on both sides of the press machine. Further, the guard plate 17 is replaced with an L-shaped guard plate 34.
At the time of fixing to the upper position, either can be used with a gap between the guard plate 17 and the L-shaped guard plate 34, or it can be fixed without opening as long as smooth movement is possible. .

FIG. 4 is a view showing a ZZ section of FIG. As described above, the angled iron plate and the L-shaped guard plate 34 are fixed to the bolster 33 by bolting or the like. The guard plate 17 is configured to overlap with an L-shaped guard plate 34 fixed to the bolster 33.

The numbers shown in FIGS. 3 and 4 represent the dimensions of the safety device, but are not limited to these. Further, the front guard, the rear guard, the side guard, and the lower guard respectively indicate the front, rear, side, and lower surfaces of the side guard.

FIG. 5 is an enlarged view of the square in FIG. As described above, the guard plate 17 moves in the front-rear direction with respect to the press machine 31 together with the optical axis a.
The guard plate 17 located on the upper guard plate 34 similarly slides in the front-rear direction with respect to the press machine 31. In addition, as for the method of fixing the L-shaped guard plate 34 to the bolster 33, various methods such as welding, bolting, press-fitting, and sticking are conceivable as in the case of the guard plate 17. Further, in addition to the above-mentioned fixing, the L-shaped guard plate 34 has a triangular auxiliary plate 51 (iron plate) fixed by welding or the like to maintain strength. In addition to the iron plate such as the auxiliary plate 51, a bar-shaped iron core may be erected diagonally below the L-shaped guard plate 34 to reinforce it.

Next, FIG. 6 shows that the guard plate 17 has a safety distance S.
FIG. 6 is a diagram for explaining a movement when moving in accordance with a change in.
FIG. 6 shows only those parts necessary for simplifying the description. In the figure, the leftmost a represents the optical axis a, and b, c, and d represent the optical axis b, the optical axis c, and the optical axis d, respectively. Further, a bolster 33 to which a lower mold (die) not shown is fixed, and an L-shaped guard plate 34 and an auxiliary plate 51 fixed to the bolster 33 are shown. The L-shaped guard plate 34 is usually fixed to the press machine side such as the bolster 33 in advance at a predetermined length below the safety device 11. Further, the presence of the L-shaped guard plate 34 can prevent the worker from entering from below. However, when the size of the mold is changed to a small one, the safety device S can be moved to the optimum position.
Since the safety device 11 is fixed, it protrudes toward the worker by an amount corresponding to the movement of the safety device 11. This is very troublesome when performing the work, resulting in poor work efficiency.

The hatched surface d in the figure indicates the position immediately before the upper die (die) (not shown) descends most. That is, it indicates the position of the optical axis d.
First, it is assumed that the guard plate fixed to the optical axis a is at the position a. Then, the mold is changed to a smaller one. Then, the optical axis d moves to the position indicated by the arrow. That is, as the mold becomes smaller, the safety distance S moves toward the press machine (not shown) and becomes the surface d ′. In the safety device 11, since the optical axis d and the optical axis a are integrated while securing the safety distance S, the guard plate 17 fixed to the optical axis a remains L as it is.
While sliding on the surface of the U-shaped guard plate 34, it moves toward the press machine.

Note that the depth length D of the guard plate 17 sufficiently overlaps with the L-shaped guard plate 34 even when the optical axis a is moved to the front, and the optical axis a is moved to the farthest position. Set so that it does not hit the mold even when moved to. Also, L
The depth E of the U-shaped guard plate 34 is naturally the safety distance S
The distance is not particularly limited as long as it is shorter and does not disturb the worker according to the distance D.

As described above, since the optical axis a and the guard plate 17 maintaining the safety distance S are of an integral structure, the safety distance S
The guard plate 17 does not protrude excessively even if the value changes. Conversely, even when the mold is changed to a larger one, only the safety device 11 moves to the front and the guard plate 17 is moved.
And the gaps are no longer short.

In the description of the above embodiment, the PSD
Although the guard plate is provided on the light beam type safety device equipped with the I function, the present invention is not limited to this, and any light beam type safety device can be applied.

[0041]

As described above, according to the present invention, the size of the mold can be reduced by integrating the optical axis provided on the worker side between the safety distances S and the guard plate for preventing entry from below. Even if the safety distance S changes when the guard plate is changed, the guard plate moves together with the light beam type safety device, so that the guard plate may be in the way or the guard plate may not be long enough to create a gap. And a safe and efficient light beam type safety device can be provided to the operator.

[Brief description of the drawings]

FIG. 1 is a sectional view of a light beam type safety device according to the present embodiment.

FIG. 2 is a diagram showing a cross section taken along line AA of FIG. 1;

FIG. 3 is a front view of a light beam type safety device including a press machine in the present embodiment.

FIG. 4 is a view showing a ZZ cross section of FIG. 3;

FIG. 5 is an enlarged view of a portion surrounded by a square in FIG.

FIG. 6 is a diagram illustrating a change in the position of the guard plate with a change in the position of the safety distance S.

FIG. 7 is a diagram illustrating a basic configuration of the light beam type safety device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Ray-type safety device 12 Fixed frame 13-16 Pipe 13 'Pipe 17 Guard plate 18 Side guard 19 Hole 20 Cana 21-22 Pipe penetration part 31 Press machine 32 Slide 33 Bolster 34 L-shaped guard plate 35 Operation panel 36 Control panel 37 operation push button board 51 auxiliary plate 71 light emitting unit 72 light receiving unit 73 control unit

Claims (7)

[Claims] 1. A light beam type safety device for a press machine, comprising: a plurality of optical axes for forming a safety space; and an optical axis disposed at a position maintaining a safe distance S from a danger area among the plurality of optical axes. A light beam type safety device characterized in that a guard member for preventing an intruder from below is provided below. 2. The light beam type safety device according to claim 1, wherein the guard member is fixed at a position overlapping an L-shaped guard member fixed to the press machine. 3. The guard member is fixed to a first moving frame that moves in the front-rear direction with respect to the press machine, and slides on a surface of the L-shaped guard member. 2. The light beam type safety device according to item 2. 4. When the guard member and the L-shaped guard member overlap, the total length is always the safety distance S.
4. The light beam type safety device according to claim 3, wherein the length is equal to: 5. The beam-type safety device according to claim 4, wherein the safety distance S is a distance from a position immediately before a die of the press machine, and is obtained by a predetermined formula. 6. An optical axis other than the optical axis disposed at a position maintaining a safe distance S from the danger area among the plurality of optical axes, the optical axis being vertically movable with respect to the first moving frame. 6. The light beam type safety device according to claim 5, wherein the light beam type safety device is disposed on the second moving frame. 7. The light beam type safety device according to claim 6, wherein a surface of the L-shaped guard member is a bolster upper surface.