JPH0395000A - Device for adjusting die height in pressing machine - Google Patents

Abstract

PURPOSE:To accurately execute adjustment of die height by using a round disk having the specific width, specifying the specific width slit and accurately positioning even in the case of inputting fallacy signal. CONSTITUTION:In the die height adjusting device in a pressing machine, a worm shaft 12 mated with a worm wheel 13 for vertically reciprocating a worm shaft 10 and slide adjusting rod 2 is arranged. Further, a positioning device using a rotary encoder 20 set by engaging with the worm shaft 12, is arranged. In this adjusting device, the round disk having the specific width is used. Then, by specifying the specific width slit, even in the case of inputting the fallacy signal, the correct positioning is executed. By this method, even at the time of varying the velocity, the position of specific width slit can be specified.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a die height adjusting device for a press machine.

[Prior Art] Guibite adjustment employed in crank presses and the like is usually performed by rotating a connecting screw, which is a slide adjustment rod attached to the tip of a connecting rod, in the forward or reverse direction.

The die height adjustment device used for this purpose includes a drive mechanism consisting of a drive source, a plurality of worm wheels, and a worm shaft, and is usually attached to a worm shaft that is directly connected to the drive source, and detects the amount of rotation of the worm shaft. , and a positioning device using a rotary encoder or the like, which calculates the amount of rotation of the connecting screw, that is, the amount of vertical movement of the slide, from the detection results.

Then, in advance, divide the total travel distance until reaching the planned guide height point by the distance corresponding to the l pulse of the low reencoder, etc., set a corresponding count value, and until it matches this count value, , a method is adopted in which the height point is adjusted to a desired height point by continuously performing sliding movement.

Incidentally, in an actual system, a signal similar to a pulse signal obtained from a rotano encoder or the like may be input to a counter. Therefore, conventionally, a filter or the like has been installed to prevent such false signals from being manually input to the counter.

[Problems to be Solved by the Invention] However, the removal of false signals by the above-mentioned filter or the like cannot be completely performed. For this reason, the counter counts not only regular pulse signals but also false signals, resulting in a disadvantage that it is not possible to reach the correct die height point.

The present invention enables accurate die height adjustment by detecting the presence of a false signal and correcting it, and also detects and corrects the false signal even if the rotational speed of the rotary encoder changes. It is an object of the present invention to provide a die height adjustment device for a press machine equipped with a positioning device that can perform the following steps.

[Means for Solving the Problems 1] In the first embodiment of the die height adjustment device for a press machine of the present invention, a worm shaft is directly connected to a positioning drive source, and the adjustment rod is connected to a slide adjustment rod. A drive mechanism having a worm shaft that meshes with a worm wheel that directly reciprocates up and down, and a positioning device that uses a rotary encoder that is disposed to mesh with one of the worm shafts of the drive mechanism. In the die height adjustment device for a press machine, the positioning device includes a disk having slits provided at equal intervals along the circumference, and having a predetermined number of unique widths and a large number of equal width slits; A light-emitting element and a light-receiving element that transmit and receive light through the slit of the plate; a CPU means that identifies the slit with the specific width based on the pattern of light received by the light-receiving element; and a CPU that specifies the slit with the specific width calculated by counting pulses. When the slit position of the width is different from the slit position of the specific width specified by the CPU means,
means for correcting the pulse count value so as to correspond to the position of the slit having a specific width specified by the CPU means;
It is characterized by having the following.

In the second aspect of the die height adjustment device for a press machine of the present invention, instead of the positioning device in the first aspect, slits are provided at equal intervals along the circumference, and have a predetermined number of specific widths. and a shield having a circular plate having a large number of equal width slits, a light emitting element and a light receiving element that transmit and receive light through the slits of the circular plate, and a small hole provided between the light receiving element and the circular plate. a first Schmitt circuit which receives the output voltage of the light receiving element as an input and is operated at a predetermined first trigger voltage; The time required for one side of the slit in the disk to pass through the small hole in the shielding plate due to the difference in trigger voltage between the activated second Schmitt circuit and the first and second Schmitt circuits. Calculate C, and from the ratio of this to the time required for the slit in the disk to pass through the small hole in the shielding plate, identify a slit with a specific width among the slits in the disk.
If the slit position of the singular width calculated by counting the pulses is different from the slit position of the singular width specified by the CPU means, the CPU means calculates the count value of the pulses. and means for correcting the position of the slit having the specified specific width.

[Function] In the first aspect of the present invention, die height adjustment by movement of the slide is controlled in the positioning device as follows. That is, in the positioning device, light emitted from the light emitting element is received by the light receiving element through slits provided at equal intervals along the circumference of the disk. The slit consists of a predetermined number of singular width slits and a large number of equal width slits, and the interlap portion includes a singular width interlap portion on both sides adjacent to the singular width slit and a large number of equal width inklap portions. It becomes more. As a result, at constant speed, the light emitted from the light emitting element is observed by the light receiving element with a light receiving time proportional to the width of each slit, and the interlap part is observed with a non-light receiving time proportional to the width of each slit. That is, the large interlap part, the small slit part, and the large interlap part are successively detected in this order, thereby identifying the unique width slit. Then, by correcting the number of pulses when detecting this unique width slit to a predetermined value, it is possible to accurately adjust the die height.

In the second aspect of the invention, die height adjustment is controlled as follows. That is, in the positioning device,
Light emitted from the light emitting element passes through slits provided at equal intervals along the circumference of the disk and small holes in the shielding plate, and is received by the light receiving element. The output from the light receiving element is sent to two Schmitt circuits with different trigger voltages.

The outputs of the two Schmitt circuits are sent to CPU means, which calculates the time required for one side of the slit in the disk to pass through the small hole in the shielding plate. A slit with a specific width among the slits in the disc is identified from the ratio to the time required to pass through the small hole in the shielding plate. Then, by performing the same correction process as above, it is possible to accurately adjust the die height.

[Example] Hereinafter, a die height adjusting device for a press machine according to the present invention will be described with reference to the drawings.

Figure 1 shows the arrangement of the crankshaft, connecting rod, connecting screw, slide, etc.
FIGS. 2 and 3 show a die height adjusting device and its main parts according to this embodiment.

Reference numeral 1 denotes a slide on which the upper mold is attached, which is connected to a crankshaft 4 via a connecting screw 2 and a connecting rod 3, guided by a gib (not shown) attached to the press machine frame, and reciprocated up and down. It is possible. Pressing is then carried out by moving the slide 1 close to and away from a lower die attached to a bolster (not shown) fixed to the lower part of the press machine frame.

10 is a worm shaft directly connected to a positioning drive source, 11 is a worm wheel, and l2 is a worm 1 on the front end side.
2a is formed and is a worm shaft that meshes with the worm wheel 13. Note that the worm wheel Y3 is disposed to be meshed with the connecting screw 2 and to be able to reciprocate directly up and down the connecting screw 2.

A rotary encoder 20 is detachably attached to the front end of the worm shaft l2, and constitutes a positioning device.

This rotary encoder 20, as shown in FIG.
A disc 21 is rotatably locked to a rotating shaft 22 provided on the worm shaft 2 through gears 15 and 16, and a light emitting element and a light receiving element are attached to a stay 24 fixed to a gear box 17. and a photodetector 23 consisting of. Note that 25 is a digital display type die height meter.

As shown in FIG. 4(b), the disk 21 has slits 2lb, 2 provided at equal intervals along the circumference.
1d, 21f... and the interlap part 2 between them
1 a, 2 1 c, 2 1 e...
·have. The width of each slit is the same except for the slit 21d. Therefore, the slit 21d is a slit with a specific width, the other slits 2lb, 21f, etc.
... is called a slit of equal width. Also, 21c, 2
1e is referred to as an interlap portion with a specific width, and the other ink overlap portions 21a, 21g, . . . are referred to as interlap portions with a constant width. A light emitting element 231 and a light receiving element 232 are installed with the disk 21 in between. Light emitted from the light emitting element 231 is received by the light receiving element 232 through each slit of the disk 21.

In FIG. 4(c), when the disk 2l is rotating at a constant speed, the slits 2lb, 21d, 21f, etc. are observed for a light receiving time proportional to the width of each slit, and 2
1a, 21c, 21e, 21g= are observed as non-light receiving times proportional to the width of the interlap portion. That is, the large interlap portion, the small slit portion, and the large interlap portion are detected successively in this order, thereby making it possible to accurately identify the slit 2Ld having a specific width.

By the way, during accelerated rotation and decelerated rotation of the disk 21,
Since each slit has a different light receiving time depending on the speed at that time, it is not possible to specify the slit 21d having a specific width by comparing the absolute value of the light receiving time or the light receiving time of the previous and succeeding slits. Therefore, when the speed changes, a slit with a specific width must be detected using a method different from that used when the speed is constant.

FIG. 5 is a configuration diagram of a positioning device used in another embodiment of the die-high adjustment device according to the present invention, and is capable of detecting a unique width slit not only at constant speed but also when speed changes. It is the composition.

In the figure, a disk 21, a light emitting element 231, and a light receiving element 2
32 has a configuration similar to that shown in FIG. 4(a).

In this embodiment, a shielding plate 27 having a small hole 27a is provided between the disk 2l and the light receiving element 232.

6(a) to 6(i) show the relative positions of the two when an arbitrary slit passes through the small hole 27a of the shielding plate 27, and FIG. 6(j) shows the received light at that time. Element 232
represents the output of Symbols a-i in FIG. 6(j) indicate the sixth
This corresponds to the positions in Figures (a) to (i).

The output of the light receiving element 232 is transmitted through a first Schmitt circuit 28 operated with a predetermined first trigger voltage and a second Schmitt circuit 29 operated with a second trigger voltage different from the first trigger voltage. Send them to each of them. The output of the Schmitt circuit 28 is sent to the AND circuit 32 together with the output of the Schmitt circuit 29 via a NOT circuit 30. Further, the output of the Schmitt circuit 29 is connected to the AND circuit 3 together with the output of the Schmitt circuit 28 via a NOT circuit 31.
Sent to 3.

For example, the trigger voltage of the Schmitt circuit 28 is set to 3/4 V DD at the rising edge and 1/4 V oo at the falling edge.
On the other hand, the trigger voltage of the Schmitt circuit 29 is set to 2/3 ■ at the time of rising. . , 1/3■ at fall. . , the outputs of the light receiving element 232, the first Schmitt circuit 28, the second Schmitt circuit 29, the first AND circuit 32, and the second AND circuit 33 are as shown in FIG. 7(a).
~(e).

In FIG. 7(d), the H section indicated by CI is 2/3 V. D to 3/4V. ．． On the other hand, in FIG. 4(e), the H portion indicated by D represents 1/3 of the time of falling. . It represents the time from 1/4 Voo to 1/4 Voo. These times correspond to 1/12 of the time leading to FIGS. 6(f) to (i) and (a) to (d), respectively. That is, it corresponds to 1712 of the time required for one side of the slit of the disk 21 to pass through the small hole 27a of the shielding plate 27.

On the other hand, as shown in FIG. 7(b), the disk 21
The time (AI-A.) required for the slit to pass through the small hole 27a of the shielding plate 27 is measured. This time is represented by the pulse width indicated by D1 in Fig. 7(e) and the pulse width indicated by D1 in Fig. 7(d).
Divide by the arithmetic mean of the pulse widths, expressed as C. Similarly, the time required for the interlap part of the disk 21 to pass through the small hole 27a of the shielding plate 27 (A.~Ai is expressed as C+ in FIG. 7(d.) and the pulse width is shown in FIG. (e
) is divided by the arithmetic mean of the pulse widths expressed as D2.

These values mean that the faster (slower) the rotation speed of the disc 21, the shorter (longer) the time (A. to A2) required for the slit of the disc 21 to pass through the small hole 27a of the shielding plate 27. However, in response, the pulse width C. ．． D. Since D2 and D2 also become shorter (longer), they can be used to identify the slit 21d of the disc 21 having a specific width, regardless of the rotation speed of the disc 21.

The positioning device of this embodiment also has a pulse width C+. Since the arithmetic mean of D1 is used,
This is also effective when the disk 21 moves with constant acceleration.

In addition, as shown in FIGS. 6(a) to (i) and FIG. 6(j),
After determining the output of the light receiving element when an arbitrary slit passes through the small hole of the shielding plate, by using the structure of the present invention, the slits 2lb, 21d, 21f, etc. of the disk 21 can be determined.
・and the interlap parts 21a, 21c, 21e・
It is also possible to estimate the absolute length of...

In this way, the slit 21d of the disc 21 having a specific width can be specified by the positioning device using the rotary encoder configured as described above.

Next, a method for detecting when the counter counts false signals using the above-described positioning device using the rotary encoder will be described.

■Counting error detection method by identifying singular width slits.

First, the method for detecting whether the counter has counted a false signal is as follows.

The number of counted pulses X from the start when the slit 21d of the unique width of the disk 21 is detected is expressed as follows: n is the number of pulses per rotation, m is the number of rotations of circle 1 in 21 from the start, and a If is the number of pulses from the origin at the start (m=0) to the slit 21d of singular width, then X=nm+a.

Therefore, at the time when the slit 21d of a singular width is detected, the number of counted pulses It means something. For example, n=5
0. Assuming a=8, the number of pulses is "O → 200-50 → 30
0'' movement is performed.

FIG. 8 is a diagram showing the state of each movement and the number of pulses of the slit 21d having a specific width to be detected during the movement.

If the number of counted pulses as described in the column ``Number of Pulses that Detected Unique Width Slit'' in FIG. 8 is detected, the counter has not counted a false signal.

By the way, in the actual movement from 50 to 300 J, the number of counted pulses X is 58, 108, 158, 209 and 2.
59.

When the counted pulse numbers 209 and 259 are divided by the number of pulses per revolution 50, the remainder is 9, respectively. If the counter is not counting false signals, the remainder must be 8. Therefore, in such a case,
This means that the electric circuit, such as a CPU, that counts the number of pulses has mistakenly counted noise or the like unrelated to the actual amount of slide movement as pulses from the encoder.

As a result, since the output of the encoder is mechanically fixed with respect to the drive unit, an error in counting the number of pulses directly causes an error in the amount of slide movement. In the case of this example, the amount of movement should be 300 pulses, but it actually stops at the position of 299 pulses.

Next, a correction method will be described when it is detected that the counter has counted a false signal using the positioning device using the rotary encoder configured as described above.

■How to correct counting errors.

Assume that the remainder when the number of counted pulses is divided by the number of pulses per revolution n, which should originally be raJ, is now rbJ. In that case, the amendments shall be as follows.

(I) When b>a, b-a<n/2, b-*a
shall be.

(II) When baa%b-a>n/2, b -4
Let n + a.

(III) When b<a, a-b<n/2, b-Ia
shall be.

(IV) b<a. When a-b>n/2, b→1n+
Let it be a.

(V) No correction when b=a or lb-al=n/2.

For example, if n=50, (I) If a=8 and b=9, correct b=8.

In other words, x-x-i.

(IT) If a=8 and b=48, correct b=58. That is, it is set as XX+10.

(III) If a=8 and b=7, correct b=8.

In other words, it is set as XX+1.

(IV) If a = 45 and b = 3, correct b = 45. In other words, it is set as X-X-S.

FIG. 9 is a diagram illustrating the correction methods (I) to (V) above.

As is clear from FIG. 9, the above-described correction method attempts to correct the count value at point a, which is the closest to the pulse count value at that time.

In this way, even when the counter detects that it has counted a false signal, the correction method described above corrects the pulse count value while continuing the predetermined movement, instead of correcting it by returning to the origin. It is characterized by the way it is carried out.

This makes it possible to avoid drawbacks such as repeating a predetermined movement from the beginning or deviation from a predetermined movement amount in a series of movements until returning to the origin.

Note that in actual positioning devices, the number of errors in counted values due to electrical noise is at most one per revolution, and if it is sufficiently small compared to n, the above correction method is an extremely effective method. .

Further, in the above correction method, since a correction operation is performed every time a slit of a specific width is detected, it is possible to prevent errors from accumulating and causing a large deviation in the amount of movement.

Next, a method for determining the number of pulses a from the origin to the slit with a singular width at the start will be explained.

■How to determine the initial value of the singular width slit.

The first method is to manually enter the number of pulses a from the starting point to the slit 10d with a specific width using a numeric keypad or the like and store it in a non-volatile memory. The second method is to rotate the disk 21 multiple times, divide the number of counted pulses X by the number of pulses per revolution n, compare the respective remainders, and if they match, calculate the value. This is a method of storing data in non-volatile memory. This method determines the stopping position of the disk 21 at the starting point, and therefore the slit 2 of a specific width.
This is effective when the stop position of 1d cannot be visually observed.

[Effects of the Invention] According to the die height adjustment device for a press machine of the present invention, a disc having a specific width is used to identify the specific width, so that it is possible to eliminate the problem when a false signal is input. Since a positioning device that can perform accurate positioning is also used, die height adjustment can be performed extremely accurately. Furthermore, the position of the unique width slit can be specified not only when the disc of the positioning device rotates at a constant speed, but also when the speed changes.

[Brief explanation of drawings]

Fig. 1 is an assembly diagram showing the arrangement relationship of the crankshaft, connecting rod, connecting screw, slide, etc. Fig. 2 is a plan view showing the die height adjustment device according to the present invention, Fig. 3 is a partially enlarged view thereof, FIG. 4(a) is a schematic diagram of an embodiment of the positioning device of the present invention, FIG. 4(b)
are a front view of the disk shown in FIG. 4(a), and FIG. 4(c) is a front view of the disk shown in FIG.
) is a diagram showing the signal pattern of the light-receiving element shown in FIG. 4(a), FIG.
Figures (a) to (i) and (j) are diagrams showing the relative positions of the two when an arbitrary slit passes through the small hole of the shielding plate, and when an arbitrary slit passes through the small hole of the shielding plate, respectively. Figures 7(a) to (e) represent the output of the light receiving element when
) are the light receiving element, the first Schmitt circuit, the second Schmitt circuit, the first AND circuit, and the second AN, respectively.
Figure 8 shows the output of the D circuit. Figure 8 shows the state of each movement and the number of slit pulses with a specific width that should be detected during that time. Figure 9 shows the detection that the counter has counted a false signal. FIG. 4 is a diagram illustrating a correction method when 1...Slide 2...Connecting screen 3...
Connecting rod 10.12... Worm shaft 11. ,13
... Worm wheel 20 ... Rotary encoder 2l ... Disk 2lb, 21d, 21f ... Slit 2 1
a, 2 1 c, 2 1 e... Interlap section 231... Light emitting element 232... Light receiving element 26... CPU 27...・Shielding plate 27a...Small hole 28.29...Schmitt circuit 30.31...
...NOT circuit 32.33...-AND circuit

Claims (2)

[Claims] (1) Directly connected to the positioning drive source Connected to the worm shaft and slide adjustment rod. directly reciprocate the adjustment rod up and down. The worm meshing with the worm wheel a drive mechanism having a shaft; Worm shaft of any of the drive mechanisms The rotary encoder is arranged in mesh with the a positioning device using a Die height adjustment device for press machine with In, The positioning device is arranged at equal intervals along the circumference. A predetermined number of slits provided at intervals. It has a singular width of and a large number of equal width slits. A disc that passes through the disc and a slit in the disc. A light emitting element and a light receiving element that perform transmission and reception; The pattern of light received by the light receiving element Therefore, specify the slit with the specific width. Calculated by CPU means and pulse counting the slit position of the singular width, and the slit position of the singular width of said singular width specified by the CPU means. If the slit position is different, the pattern The count value of the pulse is specified by the CPU means. corresponds to the position of the slit with the specified singular width. and a means for modifying the Die height adjustment for press machines featuring Device. (2) The die of the press machine according to claim 1 In the light adjustment device, the positioning device Instead, they are placed at equal intervals along the circumference. a slit with a predetermined number of singular widths and A disc with many equal width slits and a front Light is transmitted and received through the slit in the disc. A light-emitting element and a light-receiving element, and the light-receiving element and a small hole provided between the disc and the disc. A shielding plate is used to input the output voltage of the light receiving element. actuated with a predetermined first trigger voltage. The first Schmitt circuit that is The output voltage of the photodetector is input, and the predetermined a second shutter operated with a trigger voltage of 2; a mitt circuit, and the first and second shoes. Due to the difference in trigger voltage in the mit circuit so that one side of the slit in the disk is connected to the shield. Measure the time required to pass through the small hole in the shielding plate. This and the slit of the disk are the same as the shield. The time required to pass through the small hole in the shielding plate From the ratio, the singularity of the slits in the disk CPU means for specifying the width slit, and of the singular width calculated by Lus's counting. slit position and the CPU means. The slit position of the specified singular width is If the pulse count value is A path of singular width specified by the CPU means. Means of modification to accommodate the location of the lit. and a positioning device having Die height adjustment device for less machines.