JPH10166078A - Method for detecting erroneous attachment of die of punch press - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method to prevent a die or a press mechanism body from damaging by detecting in advance before a real working action when each upper/lower die P/D inside a turret is failed to be attached in a numerical control(NC) turret punch press. SOLUTION: The lower position of a ram of a turret changed with dies is positioned, the ram is lowered in a super low speed from the upper side of a prescribed fine dimension αmm of the upper face of die D, when the contact of both dies P, D is not detected with a touch sensor 11, the pressurizing force without increasing of the ram is detected with a pressure sensor 11, when the pressurizing force is not increased beyond a prescribed fine dimension βmm from a prescribed contact position, the ram is raised to the above point and stopped, and the turret is moved to the next die changing working, on the contrary, when the contact is detected with above touch sensor, lowering of the ram is stopped at once, and the composition is made so that the NC device 8 outputs the alarm signal 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detecting an incorrect mounting of a die of a punch press for punching a sheet metal work.

[0002]

2. Description of the Related Art In a punch press machine of this kind, for example, an NC (numerical control) turret punch press which has been frequently used in recent years, an upper / lower die (punch P / die D) is respectively moved to an upper / lower turret. The mounting is usually performed manually by an operator based on a work instruction included in the NC program.

[0003]

However, due to the above-mentioned manual work, the possibility of rarely causing an artificial mounting error is practically unavoidable.

In such a case, if the mold is a circular so-called round mold, there is no problem because it is irrelevant to the rotation direction angle at the time of mounting, but there is no problem, for example, as shown in FIG. For asymmetrical and long-sided molds, upper / lower molds P / D
If the relative angle of the rotation direction is wrong,
A so-called "crossing" phenomenon may occur, causing not only damage to both dies but also damage to the punch press machine body.

Therefore, the present invention automatically detects a mold mounting error caused by manual operation and issues a warning by an alarm, thereby outputting a mold incorrect mounting correction instruction to output a mold or machine error. An object is to provide a method for preventing damage to a main body.

[0006]

Therefore, according to the present invention, there is provided a punch press machine having upper and lower pressing means mounted with complementary upper and lower dies, respectively.
A means for detecting contact between the two dies at the regular processing start position of the pressurizing means, and a means for detecting a pressing force of the pressurizing means; When the operation is performed, when the contact detecting means does not detect the contact and the pressing force detecting means does not detect the increase in the pressure, "normal mold mounting" is displayed to the operator, while the contact detecting means However, when the contact is detected, the movement of the pressurizing means is immediately stopped, and a warning is displayed to the operator of "improper mounting of the mold" to the operator. It is an object of the present invention to achieve the above object by providing an erroneous mounting detection device.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below.
An embodiment will be described in detail with reference to the drawings.

[0008]

FIG. 1 is a schematic block diagram showing the configuration of an apparatus for detecting an erroneous mounting of a mold of an NC punch press according to the present invention.

(Structure) In the drawing, 1/2 is an upper / lower turret in which a plurality of pairs of upper / lower dies P / D are mounted in the circumferential direction, and 3 is a punch P (upper turret 1). Is a hydraulic cylinder (ram) for driving the machining. 4 is a linear solenoid valve for controlling each stroke of the hydraulic cylinder 3, 5 is a linear solenoid valve amplifier, and 6 is a hydraulic pump.

Reference numeral 7 denotes a control circuit which issues a press command signal 10 to the linear valve amplifier 5 in response to an execution command signal 9 from the NC device 8. A pressure sensor 11 is connected to a pressure chamber above the piston of the hydraulic cylinder 3, and outputs an output signal 12 to the control circuit 7.

The upper and lower working positions of the piston of the hydraulic cylinder 3 are input by a differential transformer 13 to a control circuit 7 with a ram position detection signal 14. Further, a signal 15 of each touch sensor (not shown) is input to the control circuit 7 to detect contact between the punch P and the die D.

The number 16 depends on whether or not a mold can be mounted, which will be described later.
A signal for outputting either a normal mounting signal or an erroneous mounting alarm signal to the NC device 8 is shown.

(Operation) FIG. 2 shows a flowchart of a mold changing operation sequence according to this embodiment.

First, in step S1, the ram of the upper turret 1 whose mold has been replaced is lowered automatically or manually.
The so-called "idling" operation without a workpiece is selected, and then, in step S2, the ram is rapidly lowered, and is lowered very slowly from a position of a predetermined minute dimension α mm on the upper surface of the die D (step S3). In step S5, Whether the touch sensor is activated by contacting the die D, and the pressure sensor 11
Ram processing force is increased.

If it is determined in step S5 that the touch sensor does not operate and the ram pressure does not increase, the process proceeds to step S7, where a predetermined contact position and a predetermined minute dimension β are determined.
If it does not exceed mm, the process returns to step S4 and repeats steps S5 and S6. If it does exceed mm in step S7, the ram is rapidly raised (step S8), and when it reaches the top dead center (step S9). , Stop the ram (step S
10) Move to the next die exchange operation of the turret.

In this case, if the touch of the touch sensor is detected in step S5, step S6 is skipped and the process immediately jumps to step S12 to stop the lowering of the ram. In step S13, the alarm signal 16 is sent to the NC unit 8 in step S13. It operates to output.

In the above operation sequence,
α and β values are not fixed values as parameters,
It is desirable to determine each appropriate value suitable for each purpose.

When the clearance between the punch P and the die D is extremely small, even if the punch and the die are correctly mounted on the upper and lower turrets, the ram is lowered at a very low speed in step S4, and as a result, the outer circumference of the punch blade is reduced. And the inner circumference of the die blade may be in contact with each other, so that the determination in step S5 is omitted, and even if the differential transformer 13 detects the position where the punch P is engaged with the die D, the detection value of the pressure sensor 11 rapidly increases. If not, it may be considered normal.

(Other Embodiments) Although the ram lowering mechanism of the turret punch press of the above embodiment has been described in the form of a fluid pressure drive system using the hydraulic cylinder 3, the present invention is, of course, limited to this. However, it is needless to say that other embodiments capable of ultra-low speed drive control, such as a servo motor drive mechanism, may be used.

Although the above embodiment has been described with reference to the case of a turret punch press having a plurality of pairs of metal fittings, it is needless to say that the present invention can be applied to a punch press having a single mold.

[0021]

As described above, according to the present invention, the mounting mistake at the time of exchanging the die of the punch press can be performed by the so-called "idling" operation prior to the main machining operation. By detecting the presence or absence of contact of the mold and the magnitude of the ram driving force, it is detected and a warning is given to the operator in case of incorrect mounting. Can be prevented beforehand.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram of an apparatus configuration of an embodiment.

FIG. 2 is a flowchart of a mold changing operation sequence according to the embodiment.

Fig. 3 Example of incorrect "cross-hit" of the mold

[Explanation of symbols]

 1/2 Upper / lower turret 3 Hydraulic cylinder 4 Linear solenoid valve 5 Linear valve amplifier 6 Hydraulic pump 7 Control circuit 8 NC device 9 Execution command signal 10 Press command signal 11 Pressure sensor 12 Pressure sensor output signal 13 Working transformer 14 Ram position detection Signal 15 Touch sensor output signal 16 Normal mounting or alarm signal D Die (lower) P Punch (upper)

Claims (1)

[Claims] 1. A punch press machine having upper and lower pressing means on which complementary upper and lower dies are mounted, respectively, wherein a contact between the two dies at a regular processing start position of the pressing means is detected. Means, and means for detecting the pressing force of the pressurizing means, perform an extremely low-speed idle operation without a workpiece to be processed, and the contact detecting means does not detect contact, and When the pressure detecting means does not detect an increase in pressure, "normal mold mounting" is displayed to the operator. On the other hand, when the contact detecting means detects a contact, the movement of the pressurizing means is immediately stopped. In addition, an apparatus for detecting incorrect mounting of a mold of a punch press, wherein the apparatus is configured to warn the operator of "abnormal die mounting" to the operator.