JPH0224171B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a punch press, and relates to a movement control device for a workpiece in a punch press that allows the movement of the workpiece to be accurate and enables accurate strip detection. be.

The movement of the workpiece in a conventional punch press is such that the angle of the eccentric axis of the press after punching is the value that is expected when the punch punches the workpiece of maximum thickness and completely passes through the workpiece. This was also done when the ram of the press was in contact with the punch.

However, since the movement command for the workpiece was set to correspond to the case where the workpiece has the maximum thickness, in the case of punching a thin plate, after punching, There was a problem that there was a lot of wasted time because there was a considerable amount of time left even after the punching process, and that the heat rate could not be increased, especially in high-speed punching. Generally, after the ram of the place reaches the bottom dead center and the punching process is performed, the workpiece remains in contact with the punch guide, and only the punch rises together with the ram, and the shoulder of the punch moves upward toward the punch guide. When it hits the punch, the punch unites with the punch guide and begins to rise, but the punch guide starts to move from a stationary state due to the force of the lifter spring, and the lifter spring is very weak compared to the stripping spring. Therefore, the rising speed is slow, and it is not possible to follow the ram of the press that is rising at a predetermined speed, and the ram of the press and the punch will separate, so the conventional punch press In,
There was also a problem in that even if there was no stripping error, the stripping error could occur and the drive could be stopped.

This invention has been made in view of the above, and its purpose is to provide movement control that can accurately move a workpiece in a punch press and accurately detect stripping errors. The purpose is to provide equipment.

Embodiments of the present invention will be described below with reference to the drawings.

In FIGS. 1 to 3, 1 constitutes a mold together with a die 3, and includes punch head parts 1-2 and 1-3.
The punch 1 is inserted into the hollow part of the guide 7 so as to be vertically movable, and the shoulder part 7-1 of the guide 7 is pulled by a stripping spring 9. is being forced to. 11 is configured to rotate a crankshaft (not shown) to urge a striker 13 provided at the bottom of the punch head 1-2 of the punch 1 to strike the workpiece 15 placed on the die 3. The ram 11 that performs processing is electrically insulated from the punch press body by an insulating plate 17, and a weak voltage is applied from a detection device 19. The guide is supported at a constant height within the holder 27 by a lifter spring 21, a collar 23, and a shoulder screw 25.

The detection device 19 has a circuit configuration as shown, for example, in FIG. Processing is performed based on the striker signal (ST) caused by contact with the punch press, and if the punch press is operating normally, a movement command signal for the workpiece is sent to the NC control unit (not shown) of the punch press. (AEFX) and the stripping error signal (ASM) in case of malfunction due to stripping error of punch 1.
It outputs each. Note that the detector for the rotation angle of the crankshaft may be, for example, an adjustable dog (not shown) attached to the crankshaft.
and multiple proximity sensors (not shown) that detect each dog.
The position where the top dead center of punch 1 is detected (e.g. ±40° with respect to the top dead center of the crankshaft) and the punching completion position (e.g. the rotation angle of the crankshaft is 265° to 345°)
It has a movable dog so that it can be preset. In addition, in Fig. 4, reference number 1
01, 103, 105 indicate photo couplers, and the top dead center approach signal (CU) from the ram 11;
This excludes the effects of noise on the punch completion proximity signal (EFX) and striker signal (ST). Reference numbers 107 and 109 also indicate photocouplers, which respectively supply the workpiece movement command signal (AEFX) and top dead center signal (ACU) to the NC control section of the punch press without being influenced by noise. It is for.

Figures 5 and 6 are time charts showing the operation of this embodiment. Figure 5 shows the case when the punch press is operating normally, and Figure 6 shows the case when the punch press has an abnormality due to a stripping error. show.

The operation of this embodiment will be explained with reference to the figures explained above.

First, to explain the case where the punch press is performing normal processing operations, after the power is turned on to the punch press (see Figure 1), a punching process start command is issued, and the ram 11 descends, causing the ram 11 to As the striker 13 starts biasing the punch head 1-2, the guide 7 descends against the relatively weak lifter spring 21 and presses and fixes the workpiece 15 onto the die 3. Then, the punch 1 that has descended with the guide 7 is further pushed down against the strong stripping spring 9, and at the bottom dead center of the ram 11, the workpiece 15 is punched out by the punch 1 and the die 3. (See Figure 2). Note that at this time, the guide 7 is in contact with the workpiece 15, so the lifter spring 21
is maintained at a constant length indicated by the reference symbol B with respect to the thickness of the workpiece 15, and after punching is completed, as the ram 11, which is at the bottom dead center, rises, the punch 1
is pushed up by a strong stripping spring 9, and the punch 1 is removed from the workpiece 15 by the ram 1.
The ram 11 is forcibly stripped following the rising speed of the guide 7 until it hits the shoulder 7-1 of the guide 7.
(see Figure 3).
Next, the punch 1 that hit the shoulder 7-1 starts to rise together with the guide 7 due to the lifter spring 21, but the guide 7 starts moving from a stationary state, and the force of the lifter spring 21 is applied to the stripping Since the force of the spring 9 is weaker than the force of the guide 7, the force of the guide 7
When the ram 11 starts to rise, the rising speed is small, and once the striker 13 and the punch head part 1-2 separate, and after a certain period of time, the ram 11 and the punch head part 1-2 come into contact again. By detecting this with the detection device 19, a workpiece movement command signal is output to the NC control section of the punch press, and the punching process of the next workpiece is started.

To electrically explain the operation of the above punch press when it is normal using FIGS. 4 and 5, when the power is turned on to the punch press, the reset circuit 1
The flip-flops 115 and 117 are cleared as the output signal level of the NAND circuit 113 in the NAND circuit 11 changes from low level (L) to high level (H). Also, depending on the signal from the proximity sensor for the dog attached to the crankshaft, the top dead center proximity signal (CU) is at high level (H), the punch completion proximity signal (EFX) is at low level (L),
Since the striker 13 and the punch 1 are not in contact with each other, a high level (H) is inputted to the detection device 19 as the striker signal (ST).

Then, when the ram 11 starts descending and the rotation angle of the crankshaft reaches 40 degrees, the top dead center proximity signal (CU) changes from high level (H) to low level (L), and the flip-flop 119 outputs the signal ( CU) is input from the input terminal (c), the Q119 output of the flip-flop ₁₁₉ changes from low level (L) to high level (H). However, the output signals of other circuits remain unchanged. Then, as the crankshaft further rotates, the striker signal (ST) changes from high level (H) to low level (L) due to the contact between striker 13 and punch head section 1-2, and remains in this state. After the ram 11 reaches the bottom dead center and the workpiece 15 is punched by the punch 1 and die 3, the ram 11 at the bottom dead center starts to rise. When the punch 1 hits the shoulder 7-1 of the guide 7 and the punch head 1-2 separates from the striker 13, the striker signal (ST) changes from the low level (L) to the high level. (H), and after a certain period of time, the punch head 1-2 comes into contact with the striker 13 again, and the punch completion proximity signal (EFX ) goes from low level (L) to high level (H), the output of the NAND circuit 121 goes to high level.
By changing from (H) to low level (L), a signal changing from low level (L) to high level (H) is applied to the reset (R) terminal of flip-flop 119. When cleared, the _Q119 output changes from high level (H) to low level (L). Due to the falling of the Q ₁₁₉ output,
When the output signal of the NAND circuit 123 changes from low level (L) to high level (H), the mono multivibrator 125 is operated, and a pulse signal having a predetermined pulse width is output from the _Q125 output terminal. The pulse signal is output to an inverter 127,
The signal is output via the photocoupler 107 to the NC control section of the punch press as a workpiece movement command signal (AEFX). In addition, the top dead center signal (ACU) is
By NANDing _{the 125} and ₁₂₉ outputs of the mono multivibrators 125 and 129 with the top dead center proximity signal (CU), the NC sequence of the NC control unit is determined when the punch completion and strip miss signals and the top dead center overlap. This is to avoid the trouble of NAND when there is no stripping error ( ₁₂₉ output is high level (H)) and when the workpiece movement command signal (AEFX) is not output ( ₁₂₅ is high level (H)). As the output of the circuit 130, the top dead center proximity signal CU is at high level (H)
At this time, a high level (H) signal is output to the NC control section.

Next, we will explain the case where the punch press makes a stripping error. Similar to the normal operation described above, the workpiece 15 is punched by the punch 1 and the die 3 (see Figures 1 and 3). After punching is completed, the punch 1 tries to rise following the rising speed of the ram 11, which has reached the bottom dead center, but it ends up stuck in the punched hole of the workpiece 15. Therefore, the strip is not removed from the workpiece 15, and only the ram 11 rises, and the punch 1 does not rise.
When the striker 13 and the punch head 1-2 are separated, the striker 13 and the punch head 1-2 do not come into contact again. Therefore, a stripping error signal (ASM) is output to the NC control section, and the punching is temporarily interrupted, and after eliminating the cause of the stripping error, processing is restarted.

To explain electrically the case where the above punch press causes a stripping error using FIGS. 4 and 6, until the workpiece 15 is punched,
This is the same as the normal case described above. Due to the stripping error, the punch is biting into the workpiece 15, so only the ram 11 rises and the stripper 13
is separated from the punch head section 1-2, and the Strasker signal (ST) changes from low level (L) to high level.
(H), and this high level (H) state continues, so the punch completion proximity signal (EFX) changes from low level (L) to high level (H) at the position where the crankshaft rotation angle is 265 degrees. At the point of aging, NAND circuit 13
The output of flip-flop 115 changes from high level (H) to low level (L), and the (D) terminal of flip-flop 115 changes from low level (L) to high level (H) via inverter 133.
Since the rotation angle of the crankshaft reaches 320 degrees and the top dead center proximity signal (CU) changes from low level (L) to high level (H), _Q115 of flip-flop 115 is supplied. output is low level
(L) becomes high level (H), the mono multivibrator 129 is activated, and its output
A pulse signal having a predetermined pulse width is output from Q ₁₂₉ and applied to relay drive section 135 . The relay of the drive unit 135 outputs a pulse signal of, for example, 20 to 30 msec as a strip miss signal (ASM) to the NC control unit depending on the self-holding time.

Therefore, according to this embodiment, the workpiece is moved when the re-contact between the striker provided at the tip of the ram and the punch head after punching is detected. plate thickness,
By adjusting the angle at which the punch is completed by moving the dog according to conditions such as the material, high-speed punching can be performed without wasting time according to the thickness of the workpiece. Furthermore, if a stripping error occurs, re-contact between the striker and the punch head after punching is not detected, so that the stripping error can be reliably detected.

As can be understood from the above description of the embodiments, the gist of the present invention is as described in the claims.According to the present invention, the striker can be used regardless of the thickness of the workpiece. During the rise, the striker and punch are temporarily separated,
As soon as re-contact is detected thereafter, movement of the workpiece is started. Therefore, there is no need for waiting time as in the conventional method, and the workpiece can be moved efficiently and quickly. In addition, the configuration does not detect temporary separation of the striker and punch as a stripping error, but detects a stripping error as a stripping error when re-contact between the striker and punch is not detected even after a predetermined period of time has elapsed. can be detected accurately without error.

Note that the present invention is not limited to the above-mentioned embodiments, and may be implemented in other embodiments with appropriate changes.

[Brief explanation of drawings]

Figure 1 is a state diagram of the mold when the ram is at the top dead center, Figure 2 is a diagram of the mold state when the ram is at the bottom dead center, and Figure 3 is the state diagram of the mold when the ram is at the bottom dead center. Figure 4 is an example of the circuit configuration of the detection device. Figures 5 and 6 are time charts for when the punch press operates normally and when a stripping error occurs, respectively. This shows that. (Explanation of symbols representing main parts of the figure), 1...
... Punch, 13 ... Striker, 15 ... Workpiece material, 19 ... Detection device.

Claims (1)

[Claims] 1. When the vertically movable striker 13 of the punch press comes into contact with the punch head 1-2 of the punch 1 and is lowered to rise from the bottom dead center to the top dead center, the striker 13 is temporarily moved from the punch head 1-2. a re-contact detection means for detecting re-contact after being separated; a command signal output means for outputting a movement command signal (AEFX) for moving the workpiece based on a signal from the re-contact detection means; When the re-contact detection means does not detect re-contact between the punch head section 1-2 and the striker 13 after a predetermined period of time has elapsed, a strip miss signal (ASM) is generated.
1. A movement control device for a workpiece in a punch press, comprising a stripping error detection means for outputting a stripping error.