JPH0211938Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a material gripping device for detecting displacement of a gripped material in a processing machine such as a turret punch press.

Generally, if plate displacement occurs during material processing in a processing machine such as a turret punch press, the finished product will be defective and the added value will be reduced. Furthermore, there is a risk that the processing tool itself may be damaged. Therefore, it is necessary to accurately hold the material in a predetermined position on the processing machine. However, in conventional material gripping devices, the means for detecting whether the material is gripped at an accurate position electrically detects plate displacement, and the accuracy is not sufficient.

This idea was made in view of the above-mentioned conventional problems, and it is a material gripping device that grips the material in a processing machine, and an air jet member is installed on the side of the lower jaw for gripping the material in the material gripping device. A sensor is provided, comprising a movable passive member having a curved portion that receives air ejected from a nozzle at the tip of an air ejection member at appropriate intervals; A sensing unit is provided with a switch that is activated at certain times, and an inhibit circuit is provided that can cut off the circuit of the sensing unit.

The embodiment shown in the figures will be explained in detail below. 1st
The figure shows the whole of a turret punch press 1 used in an embodiment of this invention, in which a material gripping device 5 grips the edge of a material placed on a work table 3. 5 is screwed onto a threaded rod rotated by a motor, so that the frame 7 is translated in the front-rear direction in FIG. 1. Further, the work table 3 itself is also moved in a direction parallel to the front surface of the frame 7 by being engaged with a threaded rod rotated by a motor (not shown). Due to the parallel movement of the material gripping device 5 and the parallel movement of the work table 3 in two orthogonal directions, the material gripped by the material gripping device 5 is moved to a predetermined position between the upper turret 9 and the lower turret 11. If you bring it to Then, the upper turret 9 and the lower turret 11 rotate together to position the punch 15 and die 17 having a desired shape directly below the striking element 13, and the punch 15 and die 1 are struck by the striking element 13.
A predetermined portion of the material inserted between the holes 7 is punched out.

Details of the material gripping device 5 of such a turret punch press 1 are shown in FIGS. 2 and below. Second
In the figures and FIG. 3, the material gripping device 5 has a main body 19 driven by a motor and a threaded rod, and a jaw portion 21 as a material gripping member attached thereto. The seat section 21 has a lower seat 21a and an upper seat 21b.
The upper jaw 21b opens and closes with respect to the upper jaw 1a, so that the edge of the material is gripped between the tips of the two. The sensor 23 is attached to the side surface of the lower jaw 21a by suitable fixing means such as a screw 25 and a holder 27.

The sensor 23 is connected to an air blowing member 31 which is fixed to the holder 27 with a fixing screw 29.
and a nozzle 31a at the tip of this air jetting member 31.
The passive member 33 facing the
It is made up of. This passive member 33 is urged by a spring 35 so that its tip always protrudes. Although not shown in the figure, the pipe 37 is connected from an external air source to the air nozzle 3.
The air ejected from 1a is received at the curved portion 33a of the passive member 33.

Note that the lock nut 39 is connected to the air jetting member 3.
1 is attached to a predetermined position of the holder 27 with a fixing screw 29 and then locked.

FIG. 4 shows a detection circuit for detecting plate displacement using the sensor 23, and air is supplied from an air source to the regulator 43 via the connector 41. Air at a constant pressure is supplied from the regulator 43 to the sensing unit 45. The sensor 23 is connected to the sensing unit 45, and the sensor 2
Air at a constant pressure is supplied to the air jetting member 31 of No. 3. Here, the plurality of sensors 23 and sensing units 45 are provided because a plurality of material gripping devices 5 are attached to the punch press 1 as a processing machine, and the sensor 23 and sensing unit 45 are provided for each of the material gripping devices 5. This is to provide a. A switch 47 that is activated by changes in air pressure is attached to the sensing unit 45, and this switch 47 is connected in series with an emergency push button switch 49. Further, an inhibit circuit 51 is connected in parallel to disconnect the sensing unit 45.

The operation of the material gripping device having the above configuration will be explained next. The material is placed on the work table 3, and both gripping devices 5 grip the edges of the material. At this time, as shown in FIGS. 2 and 3, the material is gripped so that the edge of the material just contacts the tip end surface of the jaw section 21 of the material gripping device 5. Therefore, as shown in FIG. 3, the edge of the material is aligned with the line L that coincides with the front end surface of the lower jaw 21a. Then, the tip of the passive member 33 of the sensor 23 comes into contact with the end face of this material, and the passive member 33 retracts against the force of the spring 35 so as to be aligned exactly on the line L. This is the normal state, and the distance between the curved portion 33a and the nozzle 31a is a predetermined constant distance. Therefore, the pressure of the air ejected from the nozzle 31a is also a predetermined value, and the sensing unit 45 detects the air pressure as being constant. As a result, the sensing switch 47 provided in the sensing unit 45 in FIG. 4 is in the closed state, and material feeding continues.

When the material is not completely gripped, for example, when the material is gripped by both material gripping devices 5, 5 in a slightly slanted state, one of the material gripping devices 5,
The end surface of the material does not come into tight contact with the distal end surface of the jaw portion 21, and as a result, the passive member 33 of the sensor 23 is slightly protruded by the force of the spring 35. Therefore, the distance between the nozzle 31a of the air jetting member 31 and the curved portion 33a of the passive member 33 becomes slightly wider, and the pressure of the air jetted from the nozzle 31a decreases. This decrease in air pressure is detected by the sensing unit 45, and as a result, the sensing switch 47 is opened. When the sensing unit 47 is opened in this manner, the emergency state is the same as when the emergency switch 49 is opened, and the material feeding is stopped in an emergency.

If it is desired to inhibit the circuit until the sensor 23 is replaced due to a malfunction of the sensor 23 or for other reasons, the switch 53 in the inhibit circuit 51 is closed, thereby blocking the detection circuit. You can inhibit it.

As can be understood from the above description of the embodiments, this invention is basically a material gripping device for gripping a material in a processing machine, and a side surface of the lower jaw 21a for gripping the material in the material gripping device 5. A sensor 23 is provided which includes an air ejection member 31 and a movable passive member 33 having curved portions 33a that receive air ejected from a nozzle 31a at the tip of the air ejection member 31 at appropriate intervals,
A sensing unit 45 is provided with a switch 47 that is activated when the air pressure is below a predetermined value due to a change in the interval, and an inhibit circuit 51 that can cut off the circuit of the sensing unit 45 is provided.

As is clear from the above configuration, in the present invention, a sensor 23 is provided on the side surface of the lower jaw 21a of the gripping device 5, which detects the deviation of the material by detecting changes in air pressure. It is possible to detect slight deviations with high precision. Furthermore, since an inhibit circuit 51 is provided that can cut off the circuit of the sensing unit 45 equipped with the switch 47 linked to the sensor 23, the operation of the circuit of the sensing unit 45 can be stopped in the event that the sensor 23 or the like breaks down. This can prevent problems caused by the switch 47 being activated inadvertently in the event of a failure or the like.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a turret punch press used in an embodiment of this invention, Fig. 2 is a perspective view of a material gripping device in an embodiment of this invention, and Fig. 3 is a perspective view of a material gripping device of an embodiment of the invention. FIG. 4 is an enlarged plan view of the portion where the sensor is attached to the gripping member, and is a block diagram of the plate displacement detection circuit used in the same. DESCRIPTION OF SYMBOLS 1... Turret punch press, 5... Material gripping device, 19... Main body part, 21... Jyo part, 23
...Sensor, 31...Air blowing member, 33...Passive member.

Claims (1)

[Scope of utility model registration request] As a material gripping device for gripping a material in a processing machine, an air jetting member 31 is provided on the side surface of a lower jaw 21a for gripping a material in the material gripping device 5.
and a curved portion 3 that receives air ejected from the nozzle 31a at the tip of the air ejection member 31 at appropriate intervals.
3a, and a switch 47 that is activated when the air pressure is below a predetermined value due to a change in the interval.
A material gripping device characterized in that it is provided with a sensing unit 45 having the following functions, and an inhibit circuit 51 capable of cutting off the circuit of the sensing unit 45.