JPS6357164B2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field This invention relates to a processing machine that processes a workpiece by reciprocating a processing tool relative to the workpiece, and particularly relates to a processing machine that processes a workpiece by reciprocating a processing tool relative to the workpiece. The present invention relates to a processing machine that can monitor the feeding status during processing.

Prior Art As a method for detecting the feed rate (condition) from the original position of the processing tool to the workpiece position, the applicant has developed An encoder with a number of transparent slits arranged at equal intervals on the circumferential surface is installed, and a detection device is installed to detect the passage of the slit, which rotates as the drive shaft rotates.After the previous slit has passed, Calculate the time required for the next slit to pass, compare the calculated time with the preset time, and if the calculated time is longer than the preset time, the processing tool is fed normally. The application was filed first if it was determined that it was not.

However, in this device, when the feed speed and rotation speed of the processing tool are changed by changing the rotation ratio of the drive shaft, the setting time is required to determine the feed speed that is suitable for the feed speed each time. I had to reconfigure it. Moreover, the setting work was extremely troublesome and significantly reduced the efficiency of the preparation work.

Purpose This invention was made to solve the above problems, and its purpose is to detect abnormalities in the feed speed each time even if the feed speed of the processing tool is changed according to the workpiece. To provide a processing machine which eliminates the need to correct the setting time, eliminates the troublesome setting work, and improves the efficiency of the preparation work.

Embodiment Hereinafter, an embodiment in which the present invention is embodied in a tap board will be described with reference to the drawings.

In FIG. 1, a motor 1 is a motor that is attached to a machine frame (not shown) of a tap board and is rotatable in forward and reverse directions, and has a drive pulley 2 attached to its rotating shaft. The drive shaft 3 is provided with a driven pulley 4 at the upper part, a wide gear 5 at an approximately intermediate position, and a worm 6 at the lower end. motor 1
The drive is connected to the

The main shaft 8 has a main shaft gear 9 fixedly attached to its upper end that meshes with the wide width gear 5, and a tap 11 as a processing tool is attached to the tip of the main shaft 8 via a tap chuck 10. The main shaft cylinder 12 is supported so as to be able to reciprocate in the axial direction with respect to the machine frame, and the main shaft 8
A rack 13 is formed on the outer surface of the rack. A spring 14 is interposed within the main shaft cylinder 12 and eliminates backflash.

Worm wheel 16 fixed to driven shaft 15
meshes with the worm 6 of the drive shaft 3, and the gear 1
The rotary shaft 19 is rotated through the shafts 7 and 18. A pinion shaft 20 has a pinion 21 that engages with the rack 13 of the main shaft cylinder 12, and is operatively connected to the rotary shaft 19 via a multi-disc clutch device 22 which is released when excessive torque is applied. Then, due to the forward rotation of the motor 1, the pinion shaft 20 is rotated counterclockwise in FIG. At the same time, the main shaft 8 is rotated in the forward direction to thread a pilot hole previously formed in a workpiece (not shown). Furthermore, when the motor 1 rotates in the reverse direction, the main shaft cylinder 12 moves upward (backwards), and the main shaft 8 rotates in the reverse direction to extract the tap 11 from the workpiece, completing one machining cycle. There is.

A rotary disk 23 is fixed to the pinion shaft 20,
As shown in FIG. 2, a detection notch 24 for detecting the original position (the uppermost position of the tap 11) is formed at one location on the outer circumference, and 46 slits 25 are formed on the concentric circumferential surface. is transparent. The slit 25 has a center angle on the clockwise side in FIG. 2 with respect to the base line L connecting the notch 24 and the center point O.
They are also transparently installed on the concentric circumferential surface at equal angular intervals with a center angle of 6.5° from positions spaced apart by 17.5°.

The photointerrupter 26 includes light emitting diodes 26 provided on both sides of the rotary disk 23 as shown in FIG.
a and a phototransistor 26b, and is arranged so that the phototransistor 26b receives light from the light emitting diode 26a through the notch 24 when the tap 11 is in its original position. The photointerrupter 27 is also connected to the rotary disk 2.
The light emitting diode 27a and the phototransistor 27b are arranged opposite to the slit 25, and when the tap 11 is in its original position, the light emitting diode 27a and the phototransistor 27b are arranged on both sides of the base line L. It is arranged so as to be opposed to the nearest slit 25 at a position deviated by 6.5 degrees toward the base line L side. In this embodiment, the rotary plate 2 is arranged so that the pitch between the slits 25 is 6.5°, which corresponds to 1 mm of the downward or upward movement of the tap 11.
3 rotates, and the phototransistor 27b intermittently receives light from the light emitting diode 27a, generating one pulse of a detection signal SG2 (described later), which is calculated by a control circuit (described later) as a tap movement amount of 1 mm. It's summery.

Next, an electric circuit for controlling the operation of the tap board configured as described above will be explained.

In FIG. 4, the home position detection device 31 includes the photointerrupter 26, and when the tap 11 is at the home position, it has a positive potential (hereinafter referred to as H level);
Also, when it is not at the home position, it outputs the home position signal SG1 which has a zero potential (hereinafter referred to as L level). The feed detection device 32 includes the photointerrupter 27, and when the photointerrupter 27 detects passage of the slit 25 formed in the rotary disk 23, it outputs an H level detection signal SG2. Therefore, the time interval at which the detection signal SG2 is output changes relative to the rotational speed of the rotary disk 23, that is, the vertical movement speed of the tap 11. The start switch 33 is provided at a predetermined position on the machine frame and outputs an H level start signal SG3.

The travel amount setting device 34 includes a stroke setting dial (not shown) provided at a predetermined position on the machine frame,
Code signal SG4 determines the vertical movement range of tap 11 by operating the same dial appropriately.
Output. The control circuit 35 as a feeding device receives the origin signal SG1, the detection signal SG2, and the starting signal SG.
3 and code signal SG4, each signal SG
1 to SG4, a forward rotation signal SG5 at H level is output to the forward rotation drive circuit 36, or a reverse rotation signal SG6 at H level is outputted to the reverse rotation drive circuit 37, so that the motor 1 is driven in the forward and reverse directions. It's summery.

When the control circuit 35 of this embodiment does not receive the H-level starting signal SG3, it maintains the motor 1 in a stopped state without outputting either the H-level forward rotation signal SG5 or the reverse rotation signal SG6,
Also, when the H level start signal SG3 is input while the H level origin signal SG1 is being input,
That is, when the start switch 33 is turned on while the tap 11 is stationary at the original position, the forward rotation signal SG5 of H level is outputted to cause the motor 1 to rotate forward, causing the tap 11 to move forward. Also, the control circuit 3
5 is a feed detection device 32 as the tap 11 moves forward.
The detection signal SG2 outputted from the tap 11 is counted, and the count content (the amount of forward movement of the tap 11) is compared with the value of the code signal SG4 (the preset vertical movement range of the tap 11, that is, the amount of forward movement). When it matches the value of code signal SG4,
That is, when the tap 11 moves forward by a preset forward movement amount, the H level forward rotation signal SG5 disappears and the H level reverse rotation signal SG6 is output to reverse the motor 1 from normal rotation, and the tap 11 is turned off. Return immediately. Further, when the tap 11 moves back and returns to the home position and the home position detection device 31 outputs the home position signal SG1 at the H level, the control circuit 35 eliminates the reverse rotation signal SG6 at the H level and starts the motor. 1
The tap 11 is stopped at its original position.

Therefore, the reciprocating movement of the tap 11, ie, one machining cycle of the workpiece, is controlled by the control circuit 35.

Further, the control circuit 35 controls the origin signal SG.
1. An abnormality signal SG7 at an H level from a feeding abnormality detection circuit 38 serving as a feeding condition monitoring device for monitoring the feeding condition of the tap 11 based on the detection signal SG2 and the normal rotation signal SG5 is inputted;
In response to this H-level abnormal signal SG7, the motor 1 which is currently rotating in the normal direction is immediately driven in the reverse direction, and the tap 1 is turned on.
1 to return to its original position. The details of this feed abnormality detection circuit 38 will be explained below with reference to FIG.

The clock oscillation circuit 41 is connected to the feed detection device 32.
The clock pulse SG8 is outputted at a generation interval shorter than the generation interval of the detection signal SG2 outputted from the clock pulse SG8. The AND circuit 42 is connected to the clock pulse SG8.
and the origin signal SG1 via the knot circuit 43, and outputs the clock pulse SG8 only when the origin signal SG1 is at the L level, that is, when the tap 11 is not at the original position. The counter 44 inputs the origin signal SG1 to the clear input terminal via the knot circuit 45, and also receives the detection signal SG2 from the feed detection device 32 to the clock input terminal.
Enter. The counter 44 is cleared when a falling signal falling from H level to L level is input to the clear input terminal, that is, when the tap 11 returns to its original position, it is cleared and outputs an L level output signal SG9. , Also, after being cleared, an H level signal is sent to the clear input terminal (the origin signal SG1 is L).
When two detection signals SG2 (rising signal) are input to the clock input terminal while the signal (level) is being input, the count is increased and an H level output signal is output.
It continues to output until SG9 is cleared again.

The note circuit 46 inverts the level of the output signal SG9 and outputs it as an addition/subtraction control signal SG10. The waveform shaping circuit 47 outputs a preset signal SG11 having a pulse width of 0.6 ms in response to the rise of the detection signal SG2. The AND circuit 48 is configured to input the preset signal SG11 and the output signal SG9 from the counter 44,
The preset signal SG11 is output only when the output signal SG9 is at H level, that is, when the counter 44 is counting up.

The up-down counter 49 receives the clock pulse SG8 at the clock input terminal, the origin signal SG1 at the clear input terminal, the addition/subtraction control signal SG10 at the up-down input terminal, the preset signal SG11 at the load input terminal, and the above-mentioned signal through the note circuit 50 at the carry input terminal. A normal rotation signal SG5 is input to each of them. Updown counter 4
9 adds and counts the clock pulse SG8 when the addition/subtraction control signal SG10 is at H level. or,
The up/down counter 49 receives the addition/subtraction control signal.
When SG10 is at L level, subtraction counting is performed, and the preset signal SG11
Each time the clock pulse SG8 is input, the latch contents loaded from the latch circuit 51 are subtracted by the clock pulse SG8. And the same up-down counter 49
is H when the subtraction count becomes negative.
A level abnormality signal SG7 is output. Incidentally, the up-down counter 49 receives the origin signal of the H level.
When SG1 is input, all the contents of the count are cleared. Further, the up-down counter 49 performs the above-mentioned counting operation only when the normal rotation signal SG5 at the H level is inputted through the NOT circuit 50.

The latch circuit 51 is configured to input the addition/subtraction control signal SG10 to the clock input terminal, and when the signal SG10 is at H level, inputs the count contents of the up/down counter 49, and
When the signal SG10 falls from the H level to the L level, the count contents of the up-down counter 49 at that time are latched.

Next, the operation of the tap board constructed as described above will be explained.

Now, when the tap 11 is stationary at the original position, the up-down counter 49 and the counter 44 are cleared by the origin signal SG1 at the H level, and the counter 44 outputs the signal SG9 at the H level. When the power switch (not shown) is turned on from this state, each electric circuit is initialized and clock pulses are generated from the clock pulse oscillation circuit 41.
SG8 is output. Subsequently, when the start switch 33 is pressed and a start signal SG3 is outputted to the control circuit 35, the control circuit 35 outputs a normal rotation signal SG5 of H level to drive the motor 1 in normal rotation. Then, the tap 11 starts to move forward while rotating.

At the same time, the home position detection device 31 outputs the home position signal SG1 falling from the H level to the L level to the counter 44 and the AND circuit 42 via the NOT circuits 45 and 43, respectively. Further, the AND circuit 42 outputs the clock pulse SG8 from the clock oscillation circuit 41 to the up-down counter 49 based on the origin signal SG1 at the L level.

The up-down counter 49 starts an addition count operation of the clock pulse SG8 based on the origin signal SG1 at the L level, the normal rotation signal SG5 at the H level, and the addition/subtraction control signal SG10 at the H level, and always latches the count contents. circuit 51
Output to.

Then, the rotary disk 23 rotates 13 degrees (=6.5 degrees + 6.5 degrees), the photointerrupter 27 of the feed detection device 32 detects passage of the second slit 25, and the counter 44 counts up. , the output signal SG9 of the counter 44 becomes H level, and the addition/subtraction control signal SG10 becomes L level. When the control signal SG10 becomes L level, the latch circuit 51 latches the addition count contents of the up-down counter 49 up to that point. Therefore,
The contents latched in the latch circuit 51 are stored on the rotary disk 23.
is rotated by 13 degrees, that is, tap 11 is rotated by 2 mm.
This corresponds to the number of clock pulses SG8 output during forward movement.

Further, the up-down counter 49 changes to a subtractive counting operation, loads the latch contents of the latch circuit 51 based on the preset signal SG11 output from the AND circuit 48, and then sequentially outputs the latch contents from the AND circuit 42. It is subtracted by clock pulse SG8.

When the rotary disk 23 further rotates by 6.5 degrees, the third detection signal SG2 is output from the feed detection device 32.
A preset signal SG11 is inputted to the up-down counter 49 from the AND circuit 48. The up-down counter 49 receives this preset signal SG1.
1, the count contents that have been subtracted so far are cleared and the latch circuit 51 is reset again.
Load the latch contents of and preset the contents. Then, the up-down counter 49 performs subtraction counting again using the clock pulse SG8 based on the preset contents.

The contents of the subtraction count until this preset is performed are as follows:
That is, when the tap 11 is moving forward at a constant speed, the number of clock pulses SG8 output from one preset to the next (while the rotary disk 23 rotates 6.5 degrees) is the latch content. Since it is smaller, it will never be a negative value.
Therefore, when the tap 11 is moving normally, the subtraction counting operation is repeated.

Also, if some kind of load is applied to the tap board during the forward movement and the multi-disc clutch device 22 slips, the forward movement speed of the tap 11 will slow down, and the rotating speed of the rotary disk 23 will slow down, causing a delay from one preset to the next. The number of clock pulses SG8 output during this period will be greater than the latch contents. Then, the up-down counter 49 subtracts all the latched contents until the next preset and becomes a negative value. When the content of the subtraction count becomes a negative value, the up-down counter 49 outputs an H-level abnormal signal SG7 to the control circuit 35.

In response to this abnormal signal SG7, the control circuit 35 immediately eliminates the normal rotation signal SG5 at the H level and outputs the reverse rotation signal SG6 at the H level to drive the motor 1 in the reverse direction. Then, when the tap 11 returns to its original position, the motor 1 is stopped. On the other hand, the up-down counter 49 of the feed abnormality detection circuit 38 stops its counting operation when the normal rotation signal SG5 disappears, and is cleared by the origin signal SG1 at H level. Further, the counter 44 is also cleared by the origin signal SG1 at H level.

In this way, in this embodiment, each time a machining operation is performed in one machining cycle, the forward movement speed of the tap 11, which serves as a reference, is automatically adjusted in advance when the forward movement of the tap 11 is started. By determining whether the forward speed of the tap 11 has become larger than the standard forward speed, the forward speed of the tap 11 can be calculated from There is no need to adjust the allowable forward speed in the speed.
Therefore, the troublesomeness of the adjustment work can be eliminated, and the efficiency of the preparation work can be improved.

In this embodiment, the contents latched by the latch circuit 51 (the number of clock pulses SG8 to be added) are determined by the interval between the two slits 25 on the base line L side and the generation interval of the clock pulse SG8.
By changing these intervals or occurrence intervals, or by changing the count-up number of the counter 44, the latch contents may be changed as appropriate without departing from the spirit of the present invention. Moreover, it may be applied to processing machines other than tap machines. Furthermore, the timing for latching to the latch circuit 51 was when the tap 11 started to move downward from the original position, but the tap 1
1 may contact the workpiece, the up-down counter 49 may be incremented at an appropriate time, and the content of the incremented count may be latched in the latch circuit 51.

Effects As detailed above, even if the feed speed of the processing tool is changed to match the workpiece, the reference value for detecting feed speed abnormalities can be automatically set each time. There is no need for the operator to set and correct the reference value, which eliminates the hassle and improves the efficiency of preparatory work.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the main parts of a tap board embodying the present invention, Figs. 2 and 3 are front and side views of the rotating board, Fig. 4 is an electrical block circuit diagram of the tap board, and Fig. 5. 1 is an electrical block circuit diagram of a feed abnormality detection circuit. Motor...1, Tap as a processing tool...1
1. Rotating shaft...19, Pinion shaft...20, Rotating disc...23, Notch...24, Slit...2
5. Photointerrupter...26, Home position detection device...31, Feeding detection device...32, Start switch...33, Main control circuit for feeding device...35,
Feed abnormality detection circuit...38, clock oscillation circuit...
...41, counter...44, up/down counter...49, latch circuit...51.

Claims (1)

[Claims] 1. A feeding device 1, 35, etc. that reciprocates the processing tool 11 relative to the workpiece, and a unit feed amount of the processing tool 11 sent by the feeding device 1, 35, etc. The processing tool 11 is provided with a feed detection device 32 that generates a detection signal SG2 every time the processing tool 11 is moved forward by a preset amount, and then moved back to the original position, and the processing work is performed at least during the forward movement. In such a processing machine, the detection signal from the feed detection device 32 before the processing tool 11 contacts the workpiece during forward movement
At least one time interval between SG2 is stored as a reference time, and the detection signal SG generated after that time is stored as a reference time.
The processing machine is equipped with a feeding state monitoring device that monitors the feeding state of the processing tool 11 by comparing the time interval between the two times with the reference time. 2. The feed status monitoring device compares the time interval between detection signals SG2 generated thereafter with the stored reference time, and when the interval is larger than the reference time, the feed state monitoring device generates an abnormal signal SG7. The processing machine according to claim 1, characterized in that it includes an abnormality detection device 38. 3. The feed abnormality detection device includes a clock oscillation circuit 41 that generates a clock pulse SG8 having a predetermined interval shorter than the generation interval of the detection signal SG2, and a predetermined number of the detection signals when the processing tool 11 starts forward movement. When SG2 is detected, output signal SG9
an up-down counter 49 having a preset function into which the clock pulse SG8 from the clock oscillation circuit 41 and the output signal SG9 of the counter 44 are input; and the count contents of the up-down counter 49 are latched. A clock pulse SG8 is input to the up-down counter 49 as the processing tool 11 starts to move forward, and the count contents of the up-down counter 49 are transferred to the latch circuit by the output signal SG9 from the counter 44. Further, the contents of the latch circuit 51 are preset to the up-down counter 49 every time the detection signal SG2 is generated, and the up-down counter 49 is
a logic circuit that counts down the preset contents of the up-down counter 49 using the clock pulse SG8, and generates an abnormal signal SG7 when the contents of the up-down counter 49 become less than a predetermined value. range 2nd
Processing machines listed in section.