JPS62239880A - Work-piece carriage mechanism in automatic reciprocating superfinishing planer - Google Patents

Abstract

PURPOSE:To allow a carriage mechanism to grasp the position of a termination in the sending direction of machined materials with high precision, by counting the migration distance of machined materials to perform an automatic reciprocating carriage. CONSTITUTION:A table 2 with a plane edge 10 is provided on a base 1. Above the plane edge 10 is provided a head 5 movable upward and downward supported by a pair of column 3. To the head 5 are fitted a driving roller 7 linked with an AC commutator motor 6 and a driven roller 8 as well as a sending belt 9 between these two rollers. Detectors 12 and 13 are provided on the table 2 to detect the termination of the sending direction of machined materials. In accordance with the sending distance of machined materials pulses are generated. When this pulse is counted up to a specific counting value, the power is turned OFF for the AC commutator motor 6. After that an electromagnetic brake is driven.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an automatic reciprocating mechanism for a superfinishing planer driven by an AC commutator motor.

[Background of the invention]

In order to stop the workpiece at a predetermined position and reverse the material feeding direction on a super finishing plane machine driven by an AC commutator motor, the AC! Since the inertia of the Ifi motor is large, a braking device is required.

Conventionally, the motor has a configuration as shown in FIGS. 8 and 9, and a dynamic braking circuit that utilizes the back electromotive voltage of the AC commutator motor 6. In Fig. 9, relay contact X controls the operation/stop of the AC 141 commutator motor 6, relay contact Y controls normal rotation/reverse rotation, and between the common terminal of relay contact Y, there is a brake coil B and a variable resistor VR. and the b contact of relay contact X were connected in series. In this conventional method, a of relay contact
When the contact is closed and the B contact is opened, the AC commutator motor 6 rotates forward, the material conveying belt 9 rotates counterclockwise, and the workpiece 11 is rotated in the counterclockwise direction.
When I send it, it becomes K. After the end of the feed direction is detected by the detector 12, after a certain period of time T has elapsed, the a contact of the relay contact X is opened to cut off the power to the AC commutator motor, and at the same time the b contact of the relay contact is closed. Therefore, Ate ') b1 contact of relay contact Y, brake coil 81% variable resistance VR
, the b contact of the IJ relay contact X, and the relay contact IDb2 contact form a closed circuit, a braking current flows, and the AC commutator motor 6 is braked to a stop.

(l) In the AC commutator motor 6, large load fluctuations occur due to power supply voltage fluctuations and depending on the shape of the workpiece 11, so the material feeding speed changes significantly. For this reason, the distance Ll over which the workpiece is forcibly fed from when the end of the workpiece 11 is detected to when the AC commutator motor 6 is powered off after a certain period of time T varies widely. Furthermore, since material feeding is stopped by dynamic braking, fluctuations in power supply voltage, material feeding load fluctuations, resistance value fluctuations due to temperature rise of the brake coil, and commutator! ! l! Due to the sliding resistance value fluctuation due to the state of flow bra tab 2 and temperature rise, and the influence of IA-induced braking @ delay, etc., the braking force varies greatly, making it impossible to maintain a stable braking distance L2 of the workpiece 11. . In order to correct the variation in the sum of the forced material feeding distance fiL1 and the braking distance L2, the resistance value of the variable resistor VR is adjusted, the braking current is changed,
Although this method uses a mechanism to adjust the braking force, due to the many uncertain fluctuation factors mentioned above, it is impossible to reliably reverse the workpiece 11 at a predetermined position with this method, and the reliability of automatic reciprocating operation is affected. There was a problem that it was not possible to secure the

(2) Furthermore, since the AC commutator motor 6 is repeatedly started, stopped, and braked, the temperature of the AC commutator motor 6 increases rapidly, and this temperature increase causes the commutator brushes to wear out quickly.
The problem was that it had a short lifespan.

[Purpose of the invention]

Objective of the present invention h1 To eliminate the above-mentioned drawbacks, in a super finishing planer equipped with an AC commutator motor, (1) the end of the workpiece is stopped by braking at a predetermined position on the material feeding path, and reversal is ensured; The objective is to improve the reliability of automatic reciprocating mechanisms. (
2) To reduce the temperature rise value of the AC commutator motor and improve the life of the commutator brush. (3) To reduce the temperature fluctuations of the braking device and improve its lifespan.

[Summary of the invention]

The present invention has the following features: (1) Even if the material feeding speed changes significantly due to power supply voltage fluctuations and material feeding load fluctuations, the feeding distance of the workpiece is counted in order to accurately determine the position of the end of the material in the feeding direction. Then, automatic reciprocating material feeding is performed.

(2) A soft start mechanism is provided to reduce the temperature rise of the AC commutator motor. (3) In order to use an electromagnetic brake that is less affected by power supply voltage fluctuations and material feeding load fluctuations as a braking device, and to improve the life of the electromagnetic brake,
AC motor 1! After the source is shut off, the workpiece is transported a predetermined distance by inertia, and when the inertial force is reduced, the electromagnetic brake is activated.

[Embodiments of the invention]

An embodiment of the present invention will be explained with reference to a front view showing a schematic configuration of an automatic reciprocating super-finishing planer shown in FIG. A table 2 having a planer blade 10 is provided above the pace 1, and above the planer blade 10 is supported by a pair of columns 3 and a screw shaft 4, and is lifted and lowered by a lifting knob (not shown) or a lifting electric motor. The head 5 is arranged as possible. The head 5 is equipped with an AC commutator motor 6 (
Hereinafter, it will be abbreviated as M. ) A driving roller 7 and a driven roller 8 are interlocked with each other, and a material conveying belt 9 is attached between both rollers. Detectors 12 and 13 are arranged on the table 2 to detect the end of the workpiece 11 in the feeding direction. FIG. 2 is an elevational view of the head 5, showing the material feeding drive system, and M
Power is transmitted from the output shaft of the
Furthermore, the drive roller 7 is driven via the speed reducer 14 to rotate the material conveying belt 9. An electromagnetic brake 15 is incorporated in the input shaft of the speed reducer 14, and is operated appropriately during material feeding to apply braking to the material feeding drive system. FIG. 3 is a diagram showing a pulse generating means that emits pulses in accordance with the feeding distance of the workpiece 11, and is a diagram showing an encoder 16 fixed to a proper position on the shaft 7a of the drive roller 7 and a detection device for detecting the presence or absence of a slit in the encoder 16. A container 17 is provided at a suitable position on the head 5.

FIG. 4 is a block circuit diagram showing a specific example of the present invention,
The operation will be explained below.

Power line 71%/1 and M S, coil, At coil and relay contacts 18a, 19m, and bidirectional semiconductor element 2
0 is connected in series with the relay contact 18a.

The Ar coil is replaced by 19m, and the electrical connection is made to allow forward and reverse rotation. Furthermore, from the power line /I, relay contacts 18al and 19al are connected in parallel to form trigger circuit 2.
1, and is connected to the 'L', T', and G terminals of the bidirectional semiconductor element through the internal circuit of the trigger circuit 21. Therefore, by closing the relay contacts 1111&, 18al, the G and T terminals of the bidirectional semiconductor element 20 are removed from the trigger circuit 21.

By applying a negative trigger pulse to the terminal, conduction is established between the T terminal and the T terminal of the bidirectional semiconductor element 20, and M is driven to rotate in the normal direction. Similarly, by closing the relay contact 19a119a1, K causes M to be driven in the reverse direction. In addition, when starting M in forward or reverse rotation, as shown in FIG. l! l]'w
In order to suppress the IL flow, the phase angle of the negative trigger pulse emitted from the trigger circuit 21 is advanced with respect to the cycle of the power supply voltage for a certain period of time t3, and the conduction angle of the bidirectional semiconductor element is increased. It has a soft start mechanism.

(Note that the soft start mechanism is common and details are omitted.) When the detectors 12 and 13 do not detect the workpiece 11, the signal is logic "H", and when it is detected, the signal is logic "L". Output. Flip-flops 22 and 23 are circuits that invert their Q outputs from logic rLJ to "H" at the rise of logic "L" to "H" in the output signals of termination detectors 12, 13, respectively. The flip-flop 22 is connected to the material conveying belt 9
is rotating in the normal direction (clockwise in FIG. 1), that is, the AND gate 31 is at logic rHJ and the logic "H
” is input to the R terminal, operation becomes possible. The flip-flop 23 indicates that the material conveying belt 9 is rotating in reverse (Fig.
(counterclockwise in <), that is, when the AND gate 32 is at the logic "II J" and the logic "H" signal is input to the R terminal via the AND gate 25, it becomes operable.

The distance counting circuit 27 is connected to the Q of the flip-flops 22 and 23.
A signal whose output is logic "I(") is received via the OR gate 26, the pulse signal from the detector 17 is counted, and when the count reaches the value n1 set in advance in the setting circuit 28, the logic becomes "H".
Outputs a single pulse of The single pulse circuit of the distance counting circuit 27 with 29 flip-flops outputs its Q output as logic "L".
” to rHJ, and inverts its Q output from logic “H” to rLJ. According to the logic rLJ of this Q output, the output of the AND gates 31 and 32 becomes the logic rLJ, and the excitation of the relay coils 18 and 19 is cut off. The distance counting circuit 33 receives the logic "H" from the Q output of the 7-lip flop 29 and outputs the signal to the detector 17.
It counts the pulse signals from , and outputs a single pulse of logic rHJ when the count reaches a value n2 set in advance in the setting circuit 34.

The retriggerable vibrator 36 is a flip-flop 29
It becomes operational when the Q output of is logic rHJ, and detector 1
With the rising edge signal of the pulse signal from 7, the output is set to logic rHJ for a preset time t1, and this logic "H" state starts from the rising edge of any n-th pulse in the pulse signal of the detector 17. The period width t up to the rising edge of n+1 pulses is 1
) 1. When this happens, the logic is inverted to "L" during the period t0 from the rising edge of the n-th pulse. Therefore, before the distance counting circuit 33 counts n2 pulse signals from the detector 17, the period width t between the pulses is 1) 1. When this happens, that is, when the material feeding load is so large that it cannot be counted in n2 trenches, the signal from the retriggerable vibrator 36 is used, and in other cases, the logic rl ( The single pulse signal of J is inverted by the inverter gate 35, and a falling signal from logic rHJ to "L" is output from the output of the AND gate 37.

The timer 38 is operated by the falling signal of the AND gate 37, and a logic rHJ signal is output for a preset time t1, and the relay coil 43 is energized to contact the relay contact 43a.
is closed, the electromagnetic brake 15 is energized, and the material feeding drive system is braked and stopped. After time t1 has elapsed, timer 39
After a preset time t2, a single pulse of "L" is issued to reset the flip-flop 29, changing its Q output from logic rHJ to rLJ, and changing its Q output to logic rL.
J to rHJ K invert.

When the Q output of the flip-flop 30 is logic rHJ and the Q output of the flip-flop 29 is logic "H", the AND gate 31 is logic rHJ, the relay coil 18 is excited, the relay contacts 181 and 18al are closed, and M is positive. It becomes a turn. When the Q output of the 7 lip flop 30 is logic "H" and the Q output of the 7 lip flop 29 is logic rHJ, the AND gate 32 becomes the logic rHJ, the relay coil 19 is energized, the relay contacts 191N and 19al are closed, and the M
is reversed. Each time the flip-flop 30 receives a rising signal from the logic "L" of the Q output of the flip-flop 29 to rI (J), the flip-flop 30 inverts the Q output and the Q output,
This is a circuit that indicates the direction of rotation.

Therefore, when the workpiece 11 is fed into the workpiece path while the conveyance belt 9 rotates normally, the detection 2712 is activated by the workpiece 11 and the logic changes from "H" to rLJ.

When the workpiece 11 is fed and its terminal end passes the detector 12, rHJK is reversed from logic "L".

The flip-flop 22 is set by this rising signal, and its Q output becomes the logic rHJ.When the distance counting circuit 27 counts n1 pulse signals corresponding to the feeding distance L1 from the detector 17, the logic rHJ is set. Emit a single pulse, set flip 70 knob 29, and calculate its Q output, Q
Invert the output and set the output of AND gate 31 to logic "L"
to cut off the excitation of the relay coil 18 and close the relay contact 18.
&, open 18al and cut off the power to M. Even after the power to M is cut off, the workpiece 11 is fed due to inertia, and during this inertial feeding, the feed pressure 111L is detected from the first detector 17.
When the distance counting circuit 33 counts n2 pulse signals corresponding to 2, a logical rHJ single pulse is generated, the timer 38 is operated via the inverter 35 and the AND gate 37, and the relay is activated for a time of 1°. The coil 43 is energized, the relay contact 43a is closed, the electromagnetic brake 15 is energized,
Braking is applied to the material feeding drive system to stop the workpiece 11 at a predetermined position.

That is, during the feeding distance L2, the inertia energy of the material feeding drive system is reduced and then the material is braked to a stop, thereby improving the life of the electromagnetic brake 15. After time t, the relay coil 43 is de-energized, the relay contacts 43 & are opened, the electromagnetic brake is released, and the timer 39 is activated for time 1.
．． After that, a single pulse is emitted to reset the flip 70 knob 29, and the Q output is set to logic "L", and the Q output is set to logic J4Q "l(
J, and the output of the add/do gate 32 is a logic rHJK. According to this logic "[■"], the relay coil 19 is energized, the relay contacts 19a% 19al are closed, and the conduction angle of the bidirectional semiconductor element is gradually increased for a time t, as described above. , M is started in reverse without suppressing the starting current, the material feeding belt 9 is reversed, and the workpiece is fed in reverse. When the end of the workpiece 11 passes the detector 13 while the material conveying belt 9 is rotating in reverse, its output is reversed from VFurLJ to rHJ. The flip-flop 23 is set by this start-up signal, and its Q output becomes logic rHJ. From then on, the same operation as when the material conveying belt 9 is rotating normally is repeated, and the workpiece 11 automatically reciprocates. .

In addition, when finishing the cutting of the workpiece 11 and pulling it out to the front side (right side in FIG. 1), the material feeding belt 9 During reversal, the output of the AND gate 42 is set to logic [
HJ, the output of the AND gate 25 is set to logic "L" via the inverter gate 41, the flip-flop 23 is set to the reset state, and conversely, the output of the OR gate 24 is set to the logic "L".
f(J), enable the flip-flop 22, make the detector 12 detect the end of the workpiece 11, and after the workpiece 11 is pulled out to the front side, change the feed belt from reverse rotation to normal rotation. I'm trying to get it back.

In FIG. 4, ■ indicates a suitable circuit power supply, and v+1 indicates a power supply for the electromagnetic brake.

FIG. 6 shows a relationship diagram between the number of revolutions (N) of M and the distance (L) in which the workpiece 11 is fed after the end of the workpiece 11 is detected by the detector 12 or 13. In the figure, L1 and L2 are the traveling distances corresponding to n1 and n2 counts of pulse signals from the detector 17, respectively, and L3 is the distance that the workpiece 11 travels during braking. As shown in (11 and (2)) in the figure,
Even when the rotational speed (N) of M differs due to power supply voltage fluctuations and material feeding load fluctuations, the difference in the sum of the feeding distances (L1+L2+L3) until the workpiece 11 stops is very small, and it is almost impossible to reach the specified speed. The workpiece 11 can be stopped at any position, resulting in stable and reliable automatic reciprocation! Φ production becomes possible.

On the other hand, FIG. 7 shows a case where the control is performed using a timed operation. Assuming that the times corresponding to the feeding distances of Ll and L2 in Figure 6 (11) are TI and T2, the rotational speed (N) of M decreases due to power supply voltage fluctuations and material feeding load fluctuations and becomes 2). , time TI, and the distance traveled during 72 are L 1' (L 1'<L 1) and L 2'(L2'<
Ll), and furthermore, the traveling distance during braking becomes L3' (L
3'< L 3), and the difference ΔL' in the sum of the feeding distances at the trench where the workpiece 11 stops becomes very large, so the workpiece 11 may be pulled out of the material feeding path during automatic reciprocation. ,
Alternatively, the plane blade lO may leave cutting residue, resulting in a lack of reliability in automatic reciprocation. Therefore, the material feeding mechanism of the present invention is effective in a superfinishing planer driven by an AC commutator motor.

〔Effect of the invention〕

According to the present invention, in an automatic reciprocating superfinishing planer driven by an AC commutator motor 6, the feeding distance of the workpiece 11 is counted, the power supply of the AC commutator motor 6 is cut off, and the inertia After feeding, the electromagnetic brake 15 is actuated to brake the material feeding drive system and stop the workpiece 11, so that the material feeding speed can be significantly reduced due to power supply voltage fluctuations or material feeding load fluctuations. Even if the workpiece 11 fluctuates, the end of the workpiece 11 can be accurately braked and stopped at a predetermined position on the material feeding path, a reliable reversal operation can be performed, and the reliability of the automatic reciprocating operation can be improved.

In addition, the trigger circuit 21 having a soft start mechanism gradually increases the conduction angle of the bidirectional semiconductor element 20 to suppress the generated current and start the AC commutator motor 6, so that the alternating current commutator motor 6 is started frequently. Even if you repeatedly start and stop,
The temperature rise value of the AC V and flow motor 6 can be reduced, the life of the current brush can be greatly improved, and the life of the contacts of the forward/reverse rotation switching relay can also be greatly improved.

Further, since the electromagnetic brake 15 is driven after inertial feeding and reducing the inertial energy of the material feeding drive system, the temperature rise value of the electromagnetic brake can be reduced and the service life can be improved.

As described above, a stable, highly reliable, and economical material feeding mechanism can be provided.

[Brief explanation of drawings]

Fig. 1 is a front view showing the schematic configuration of the super finishing planer, Fig. 2 is an elevational view of the head, Fig. 3 is the detection mechanism for detecting the material feeding distance, Fig. 4 is a block circuit diagram, and Fig. 5 is a block diagram. The figure is an explanatory diagram of the starting current, Figures 6 and 7 are relationship diagrams of the rotational speed of the AC rectified pre-voltage machine and the feeding distance of the workpiece, and Figures 8 to 10 are super-finishing methods using conventional technology. They are a front view, a circuit diagram, and a time chart diagram showing a plane board. In the figure, 2 is a table, 5 is a head, 6 is an AC commutator motor, 7 is a drive roller, 8 is a driven roller, 9 is a material feeding belt, 10 is a plane blade, 11 is a workpiece, 12.13.1
7 is a detector, 14-digit reducer, 15 is an electromagnetic brake, 16
is the encoder, 18.19.43 is the relay coil, 20
is a bidirectional semiconductor device, a 21-digit trigger circuit, 22.23
．． 29.30 flip-flop, 24.26 is or gate, 25.31132.37.42 is and gate,
27.33 is a distance counting circuit, 28.34 is a setting circuit, 3
5.41 is an inverter gate, 36 is a retriggerable vibrator, 38.39 is a timer, 40 is a material drawing circuit,
18a, 18al, 19a119al, 43aXXXY
is a relay contact, R is a resistance, and RV is a variable resistance. Name of patent applicant Hitachi Koki Haramachi Co., Ltd.

Claims (1)

[Scope of Claims] 1. A material feeding path is formed by a material feeding belt driven by a reversible electric motor and a plane blade facing the material feeding belt, and the material feeding belt moves the workpiece back and forth to create a plane blade. In a super finishing planer that performs cutting, an AC commutator motor is used as the reversible motor, and a rotation direction switching circuit that controls forward rotation and reverse rotation by switching the connection of one of the S_i coil or A_r coil of the AC commutator motor. , a bidirectional semiconductor element that controls the start/stop of the AC commutator motor, and a trigger circuit that triggers the bidirectional semiconductor element, and connects the AC commutator motor, rotation direction switching circuit, and bidirectional semiconductor element. The circuit is connected in series, with an end detector for detecting the end of the feed direction of the workpiece at a suitable location on the material feeding path, and an end detector for detecting the end of the workpiece in the feeding direction, and an end detector for detecting the end of the workpiece in the feeding direction between the AC commutator motor and the material feeding belt. A pulse generating means for generating pulses according to the conveying distance is provided, a distance counting circuit receives the pulse output signal of the pulse generating means and counts the conveying distance of the workpiece, and a distance counting circuit is provided between the AC commutator motor and the material conveying belt. The power transmission unit is configured to have an electromagnetic brake as a braking device, and upon receiving the output signal of the end detector, the pulse signal of the pulse generating means is counted by a distance counting circuit, and the preset workpiece is fed. When the distance L1 is reached, the bidirectional semiconductor element and the rotation direction switching circuit are deenergized via the trigger circuit, and when the preset workpiece feeding distance L2 is reached, the electromagnetic brake is applied for a certain period of time. A material feeding mechanism in an automatic reciprocating super-finishing plane machine characterized by driving for a period of time t_1, and then energizing a rotation direction switching circuit and energizing a bidirectional semiconductor element via a trigger circuit after a time t_2 has elapsed. . 2. As a trigger circuit for the bidirectional semiconductor device, a soft start that suppresses the starting current of the AC commutator motor by gradually increasing the conduction angle for a certain period of time t_3 at the start of energization of the bidirectional semiconductor device. A material feeding mechanism in an automatic reciprocating super-finishing plane machine according to claim 1, which has a mechanism. 3. The material feeding mechanism in the automatic reciprocating super-finishing plane machine according to claim 1, wherein the material is fed by inertia over the feeding distance L2, and after reducing the inertial energy of the material feeding drive system, an electromagnetic brake is driven. 4. It has a circuit that sequentially measures the cycle width of the pulse signal from the pulse generating means while counting the feeding distance L2, and when the feeding distance L2 cannot be counted, it forcibly emits a pulse and performs automatic reciprocating operation. A material feeding mechanism in an automatic reciprocating super-finishing plane machine according to claim 1, which continues the process.