JP3573371B2 - Timing generator - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a timing generation device, and is required for polishing using a manually operated tip dresser (hand dresser) for dressing (polishing) an electrode tip of a welding machine such as a stationary spot welding machine or a multi-spot welding machine. The present invention relates to a timing generation device in a controller for performing control.
[0002]
[Prior art]
In spot spot welding machines such as stationary spot welding machines and multi-spot welding machines, if the shape is deformed due to repeated wear and tear of the electrode tip due to repeated pressurization and energization, welding quality cannot be ensured. A tip dresser for polishing an electrode tip is used.
[0003]
As a conventional chip dresser, for example, as disclosed in JP-A-1-181985, a moving body is supported on a frame fixed on a base so as to be able to move up and down, and a dresser body is fixed to the moving body. A cutter blade, which is driven by an air motor, is attached to the dresser body, and the electrode tip is polished by rotating the cutter blade with the air motor while pressing the electrode tip from above and below the cutter blade. Type tip dressers are known.
[0004]
[Problems to be solved by the invention]
However, in the conventional tip dresser described above, since it is a stationary tip dresser, one tip dresser must be installed corresponding to one welding machine. Is rising. Therefore, there is a demand for a portable tip dresser (hand dresser) that enables an operator to polish an electrode tip manually at a location where a welding machine is installed.
[0005]
By the way, when using such a hand dresser, in performing the dressing operation, the dresser main body is pressurized with a weak pressing force until the first set time elapses from the start of the dress, and the first set time elapses. Thereafter, it is desired that control can be performed such that the dresser main body is pressurized with a strong pressing force until the second set time elapses.
[0006]
In order to perform such control, two monostable multivibrators (hereinafter also referred to as "monomulti") are combined, and the first-stage monomulti is activated by an input signal (activation signal), and the first-stage monomulti is activated. An output obtained when the first set time has elapsed from the multi is set as a first signal, and the next mono multi is activated by the first signal, and the second set time is set from the next mono multi. It is conceivable to use an output obtained when elapses as the second signal.
[0007]
In this case, if an attempt is made to reset the two mono multis when the input signal is no longer input, when the two mono multis are simply combined, the transient effect of the mono multi, that is, the output from when the input signal is input, is output. Due to the characteristic that a certain delay time occurs before the transition of the two, the two mono multis are activated at the same time as the input signal is input.
[0008]
The present invention has been made in view of the above points, and has as its object to provide a timing generation device capable of generating an accurate timing signal using two mono-multis.
[0009]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, a timing generation device according to claim 1 outputs a first signal indicating that a first set time has elapsed since an input signal is input, and outputs the first set time. A first monostable multivibrator for outputting a second signal indicating that a second set time has elapsed from the time when the first set time has elapsed. Input terminal and the clear terminal, respectively, the first signal and the input signal obtained from the output terminal of the first monostable multivibrator are input to an AND circuit, and the output signal of the AND circuit is input to the AND circuit. An input terminal and a clear terminal of a second monostable multivibrator for setting a second set time are input to the output terminal of the second monostable multivibrator. And configured to obtain a second signal.
[0010]
According to a second aspect of the present invention, in the timing generation apparatus according to the first aspect, the first and second monostable multivibrators are provided with setting time adjusting means for variably setting the first and second setting times. Provided.
[0011]
[Action]
According to the first aspect of the present invention, the input signal is input from the output terminal of the first monostable multivibrator by inputting the input signal to the input terminal and the clear terminal of the first monostable multivibrator. A first signal indicating that the first set time has elapsed from the time is output, and the first signal and the input signal from the first monostable multivibrator are connected to the second monostable via the AND circuit. By inputting the signal to the input terminal and the clear terminal of the multivibrator, a second signal indicating that the second set time has elapsed after the output of the first signal from the output terminal of the second monostable multivibrator. A signal is output. At this time, the first signal and the input signal are ANDed to form the second monostable multivibrator due to the transient effect of the first monostable multivibrator. With activation of Ibureta is prevented, it is possible to reset the two monostable multivibrator when the input signal is not input.
[0012]
According to a second aspect of the present invention, in the timing generating apparatus of the first aspect, the first and second monostable multivibrators are provided with setting time adjusting means for variably setting the first and second setting times. Therefore, the first set time and the second set time can be adjusted within a required range.
[0013]
【Example】
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. 1 is an overall system configuration diagram showing one embodiment of the present invention, FIG. 2 is an exploded perspective view of a dresser main body, FIG. 3 is a block diagram of a controller, and FIG. 4 is a chattering prevention circuit, a start signal generation circuit, and an interface of FIG. FIG. 5 is a circuit diagram showing details of a lock receiving circuit and a malfunction prevention circuit, FIG. 5 is a circuit diagram showing details of a timing generation circuit of FIG. 3, and FIG. 6 is a detail of a tip dress pressure setting circuit, a welding pressure setting circuit, etc. of FIG. FIG. 7 is a circuit diagram showing details of the pressurizing valve switching circuit and the like in FIG. 3, and FIG. 8 is an external view of the controller.
[0014]
This hand dresser system comprises a dresser body 2 that can be manually rotated to grind the electrode tips 1a and 1b of the upper gun 1A and the lower gun 1B of the welding machine, and the electrode tips 1a and 1b using the dresser body 2. A controller 3 for controlling the polishing when the hand is dressed manually, a pressure drive system 4 controlled by the controller 3 to press the dresser body 2 by the electrode chips 1a and 1b during the hand dressing, and a controller. 3 is provided with a dress activation switch 5 for outputting a dress press signal S1 for instructing a dress start.
[0015]
The pressure drive system 4 of the hand dresser system is shared with the pressure drive system of the welding machine itself. Further, the controller 3 and the welding timer 6 of the welding machine to which a welding start instruction is given from the welding start switch 7 are connected for interlocking, and a welding pressurizing signal from the welding timer 6 is input to the controller 3. are doing.
[0016]
As shown in FIG. 2, the dresser body 2 holds a holder receiving member 12 at the tip end of a grip portion 11 so as to be swingable, attaches a holder 13 to the holder receiving member 12, and places a polishing tip 14 in the holder 13. The cover 15 is attached while being fixed and held.
[0017]
The pressurizing drive system 4 supplies air from the air source to the electropneumatic proportional valve 20 via the filter 16, the regulator 17 and the lubricator 18. The electropneumatic proportional valve 20 controls and sends out the air supplied to the air pressure according to the control voltage. The air from the electropneumatic proportional control valve 20 is supplied to a cylinder 22 that drives the electrode chips 1a and 1b via a pressure solenoid valve 21. The pressure solenoid valve 21 opens and closes an air supply path according to a control signal. Therefore, the controller 3 outputs the pressure level setting signal S2 to the electropneumatic proportional valve 20 to control the pressure level (dress pressure), and outputs the pressurization signal S3 to the solenoid valve 21 to pressurize / non-pressurize. Is switched.
[0018]
As shown in FIG. 3, the controller 3 includes a chattering prevention circuit 31, a start signal generation circuit 32, a timing generation circuit 33 constituting a timing generation device according to the present invention, a hold command circuit 34, a logic circuit 35, and an interface circuit 36. And a tip dress pressure setting circuit 37, a pressure valve switching circuit 38, a dress / weld changeover switch 40 and an interlock input receiving circuit 41, a malfunction prevention circuit 42, an interface circuit 43, and a welding pressure setting circuit 44.
[0019]
The chattering prevention circuit 31 shapes an output signal (dress press signal S1) of the dress start switch (PB) 5 to generate a dress start signal S5, and generates the start signal S5 via the logic circuit 35. Output to the circuit 32. The start signal generation circuit 32 inputs a dress start signal S5 from the chattering prevention circuit 31 and a hold command signal S8 from a hold command circuit 34 to be described later via a logic circuit 35, and based on these input signals, an electrode chip A start signal S6 for pressurizing the dresser body 2 is generated by 1a and 1b, and the start signal S6 is output to the welding pressurizing setting circuit 44 via the timing generating circuit 33, the pressurizing valve switching circuit 38, and the interface circuit 43. I do.
[0020]
The timing generation circuit 33 generates a timing signal S7 corresponding to a predetermined pressure pattern based on the start signal S6 from the start signal generation circuit 32, and sets the chip dress pressure via the hold command circuit 34 and the interface circuit 36. Output to the circuit 37. The hold command circuit 34 outputs a hold command signal S8 for holding the start signal S6 output from the start signal generating circuit 32 to the start signal generating circuit 32 via the logic circuit 35 in response to the timing signal S7 from the timing generating circuit 33. I do.
[0021]
Here, the “predetermined pressurization pattern” indicates a relationship between the dress pressure and the time for applying the dress pressure. In the present embodiment, the pressurizing force is determined by pre-pressing, main pressing, and finishing pressure. The pressure is set in three stages (see FIG. 12), the time for applying the pre-pressing force is the pre-pressing time (first set time), and the time for applying the pre-pressing force is the main pressing time (second time). As the set time, the timing signal of the pre-pressurization time and the main pressurization time is generated by the timing generation circuit 33.
[0022]
The tip dress pressure setting circuit 37 outputs a pressing force level setting signal S2, which is a voltage signal for setting the pressing force of the dresser body 2 by the electrode chips 1a and 1b, in accordance with the timing signal S7 from the timing generating circuit 33. Output to the empty control valve 20. The pressurizing valve switching circuit 38 outputs a pressurizing signal S3 to the pressurizing solenoid valve 21 in response to the starting signal S6 from the starting signal generating circuit 32, and pressurizes / non-presses the dresser body 2 by the electrode chips 1a and 1b. Switch pressurization.
[0023]
The dress / weld changeover switch 40 is a toggle switch, and outputs a signal corresponding to dress / weld changeover. The interlock input receiving circuit 41 shuts off the power supply to the welding timer 6 at the time of dressing in response to an input signal from the dress / weld changeover switch 40, for example. The malfunction prevention circuit 42 outputs blocking signals S9 and S10 for preventing the output of the dress start signal S1 from the chattering prevention circuit 31 and the start signal S6 from the start signal generation circuit 32 when the dress power is turned on. The welding pressurization setting circuit 44 sends a pressing force level setting signal S2 ', which is a voltage signal for setting a pressing force at the time of welding, to the electropneumatic control valve 20, in accordance with a start signal S6 from the start signal generating circuit 32. Output.
[0024]
Next, details of each unit will be described with reference to FIG. First, referring to FIG. 4, a dress start switch 5, which is start switch means, is a push button (PB) switch having an a (normally open) contact 5a and a b (normally closed) contact 5b. The chattering prevention circuit 31 includes pull-up resistors R1 and R2 for pulling up the normally open contact 5a and the normally closed contact 5b of the dress activation switch 5 to the power supply Vcc, and a negative edge going type JK flip-flop (hereinafter, referred to as a JK flip-flop). The circuit includes a circuit 51, an AND circuit 52, and a capacitor C1.
[0025]
The FF circuit 51 grounds the J terminal, the K terminal, and the CK (clock) terminal, inputs the output signal (dress press signal) S1a of the normally open contact 5a of the dress start switch 5 to the preset (PR) terminal, and clears it. The output signal (dress press signal) S1b of the normally closed contact 5b of the dress start switch 5 is input to the (CLR) terminal via the AND circuit 52. The AND circuit 52 outputs the output signal S1b of the normally-closed contact 5b of the dress start switch 5 when a blocking signal S9, which is an output of the malfunction prevention circuit 42 described later, is at a high level H (hereinafter, simply referred to as "H"). Is a gate circuit that passes through. The Q output of the FF circuit 51 is output to the start signal generation circuit 32 as the dress start signal S5a, and the inverted Q output is output as the dress start signal S5b.
[0026]
The start signal generating circuit 32 includes a negative edge going type JK type FF circuit 53, a Schmitt trigger inverter 54, and NOR gate circuits 55 and 56. The FF circuit 53 connects the J terminal, the K terminal, and the PR terminal to the power supply Vcc, inputs the output of the logic circuit 35, which is a NOR gate circuit, to the CK terminal via the Schmitt trigger inverter 54, and outputs the malfunction prevention circuit 42 to the CLR terminal. Is input. The logic circuit 35 receives the dress start signal S5b, which is the inverted Q output of the FF circuit 51 of the chattering prevention circuit 31, and the hold command signal S8 from the hold command circuit 34.
[0027]
Then, the Q output of the FF circuit 53 and the dress start signal S5a, which is the Q output of the FF circuit 51 of the chattering prevention circuit 31, are input to the NOR gate circuit 55, and the output of the NOR gate circuit 55 is sent to the blocking signal of the malfunction prevention circuit. The signal is output as a start signal S6 via a NOR gate circuit 56 having S10 as the other input.
[0028]
On the other hand, the dress / weld changeover switch 40 is a toggle-type switch. The contact a is connected to the power supply Vcc as the “dress” side, the contact b is grounded as the “weld” side, and the common contact c is interlocked. 41. The interlock receiving circuit 41 includes a relay (CR) 57, a switching transistor TR1, an input resistor R3, a diode D1, and a Schmitt trigger inverter 58, and outputs a signal S11 having a level corresponding to the state of the dress / weld changeover switch 40. .
[0029]
The malfunction prevention circuit 42 includes a delay circuit 59 including a resistor R4 and a capacitor C2, and Schmitt trigger inverters 60 and 61. The delay circuit 59 delays the signal S11 from the interlock receiving circuit 41, Signal S10 is output to the NOR gate circuit 56 of the activation signal generation circuit 32, and the inhibition signal S9 obtained via the Schmitt trigger inverter 61 is transmitted to the AND circuit 52 of the chattering prevention circuit 31 and the activation signal. Output to the FF circuit 53 of the generation circuit 32.
[0030]
Next, referring to FIG. 5, a timing generation circuit 33 includes a pre-pressurizing mono-multi 63 which is a first monostable multi-vibrator composed of a dual retriggerable monostable multi-vibrator, and a pulse of the mono multi 63. Setting time adjusting means for setting a width (pre-pressurizing time = first setting time) including a variable resistor VR1, a resistor R5, and a capacitor C3; and a second unit including a dual retriggerable monostable multivibrator. A main pressurizing monomulti 64 that is a stable multivibrator, and a set time including a variable resistor VR2, a resistor R6, and a capacitor C4 for setting a pulse width (main pressurizing time = second set time) of the monomulti 64. Adjusting means, AND circuits 65 and 66, an integrating circuit 67 including a resistor R7 and a capacitor C5, Consisting Interview mitt trigger inverter 68..
[0031]
The starting signal S6 from the starting signal generating circuit 32 is input to the pre-pressing mono-multi 63 as an input signal in the present invention, and a signal (first signal) S12 which is an inverted Q output of the pre-pressing mono-multi 63 is provided. The integration output S13 of the integration circuit 67 for integrating the start signal S6 is input to the AND circuit 65, and the output of the AND circuit 65 is input to the main mono-multi for pressurization 64, and the inverted Q output of the mono-multi 63 for pre-pressurization ( A signal S12, a signal (second signal) S14 which is an inverted Q output of the main mono-multi 64 for pressurization, and an integrated output S13 of the integrating circuit 67 are input to the AND circuit 66.
[0032]
Then, the inverted Q output S12 of the pre-pressurizing mono-multi 63, the inverted Q output S14 of the main pressurizing mono-multi 64, and the output S16 of the AND circuit 66, which are inverted by the Schmitt trigger inverter 68, are output via the interface circuit 36, respectively. In addition to the output to the tip dress pressure setting circuit 37, the Q output S 17 of the main mono-multi 64 for pressurization and the output S 18 of the AND circuit 66 are input to the hold command circuit 34.
[0033]
The hold command circuit 34 is composed of a NOR gate circuit, receives the Q output S17 of the main mono-multi 64 for pressurization and the output S18 of the AND circuit 66 as described above, and outputs the same to the logic circuit 35 as the hold command signal S8. I do.
[0034]
Next, referring to FIG. 6, the interface circuit 36 includes an inverted Q output S12 of the pre-pressurizing mono-multi 63 of the timing generation circuit 33, an inverted Q output S14 of the main pressurizing mono-multi 64, and an output of the Schmitt trigger inverter 68. It consists of three photocouplers 71 to 73 that input S16 respectively. The chip dress pressure setting circuit 37 includes resistors R10 to R12, variable resistors VR3 to VR5 connected to the output side of each of the photocouplers 71 to 73 of the interface circuit 36, a resistor R9, and diodes D2 to D5. To VR5 and the resistance values of the resistors R9 to R12 are output to the electropneumatic proportional valve 20 as a pressure level setting signal S2.
[0035]
The interface circuit 43 includes a photocoupler 74 that inputs a start signal S6 from the start signal generation circuit 32. The welding pressure setting circuit 44 includes a rotary switch 75 connected to the output side of the photocoupler 74, variable resistors VR6 to VR8, resistors R15 and diodes D5 to D7, and the resistors of the variable resistors VR6 to VR8 and the resistor R15. A voltage signal corresponding to the value is output to the electropneumatic proportional valve 20 as a pressure level setting signal S2 '.
[0036]
Next, referring to FIG. 7, the pressurizing valve switching circuit 38 includes a switching transistor TR3, a phototriac 77, a surge absorbing element 78, and resistors R13 and R14, and outputs a start signal S6 from the start signal generating circuit 32. The output is input to the transistor TR3 via the resistor R11, and the output terminal of the phototriac 77 is interposed in the power supply path to the pressure solenoid valve 21 to switch the light emitting element side. The normally open contacts CR1 and CR2 of the relay 57 of the interlock receiving circuit 41 are provided on the power supply path to the pressure solenoid valve 21. The normally-closed contact CR3 of the relay 57 outputs power to the welding timer 6 during dressing, and the normally-closed contacts CR4 and CR5 shut off the solenoid valve terminal of the welding timer 6 during dressing.
[0037]
As shown in FIG. 8, the controller 3 includes a dress / weld changeover switch 40, a rotary switch 75 for selecting welding force, variable resistors VR1 and VR2 for setting dress time, and variable resistors VR3 to VR5 for setting dress pressure. It is arranged so that it can be externally operated together with the "power on" display lamp 80. Here, each of the variable resistors VR1 to VR5 is provided so as to be operable externally while being installed on the internal PCB substrate.
[0038]
Next, the operation of the hand dresser system configured as described above will be described with reference to FIGS. First, the operation of each unit of the controller 3 will be described. The operation of the chattering prevention circuit 31 will be described. It is assumed that the dress / weld changeover switch 40 is switched to the dress state by setting the contact a to the contact a side. At this time, the transistor TR1 of the interlock receiving circuit 41 is turned on, the relay 57 is operated, and the normally open contacts CR1 and CR2 of the relay 57 interposed in the power supply path to the pressure solenoid valve 21 are closed. It has become. Further, the output signal S11 of the interlock receiving circuit 41 becomes "H", the blocking signal S10 of the malfunction preventing circuit 42 is at a low level "L" (hereinafter simply referred to as "L"), and the blocking signal S9 is "H". "It has become. As a result, the gate of the AND circuit 52 of the chattering prevention circuit 31 is open.
[0039]
When the dress start switch 5 is depressed in this state, the output signal S1a of the normally open contact 5a becomes "L", and this output signal S1a is input to the PR terminal of the FF circuit 51, and the output signal S1a of the normally closed contact 5b is The output signal S1b becomes “H”, and the output signal S1b is input to the CLR terminal of the FF circuit 51 via the open AND circuit 52.
[0040]
In this case, since chattering occurs at each contact of the push button type dress start switch 5, when the dress start switch 5 is pressed down, the output signal S1a of the normally open contact 5a of the dress start switch 5 as shown in FIG. As shown in FIG. 4A, the signal becomes chattering from "H" and then becomes "L" and becomes stable. At this time, the output signal S1b of the normally closed contact 5b becomes normally open as shown in FIG. Chattering occurs from "L" earlier than the operation of the contact "a" by a predetermined time, and then becomes "H" and is stable. When the pressing of the dress start switch 5 is released, the return of the normally open contact 5a is earlier than the return of the normally closed contact 5b, and the output signal S1a shifts to a stable state due to chattering as shown in FIG. With a delay, the output signal S1b generates chattering and shifts to a stable state.
[0041]
Here, since both the J terminal and the K terminal of the FF circuit 51 are “H”, the Q output is set to “H” when the PR terminal is “L” and the CLR terminal is “H”. Is "H" and when the CLR terminal is "L", the Q output is set to "L". Therefore, when the dress start switch 5 is depressed from the FF circuit 51 as shown in FIG. 4C, the state becomes “H” from the time when the normally open contact 5a is closed, and when the depression of the dress start switch 5 is released. When the normally closed contact 5b is closed, a Q output that becomes "L" is obtained, and this Q output is output as a dress start signal S5a, and as shown in FIG. Is output as the dress start signal S5b.
[0042]
As described above, the output including the chattering of each contact of the dress start switch 5 is performed by using the dress start switch 5 which is a push button switch having the a contact and the b contact, and the circuit including the resistors R1 and R2 and the FF circuit 51. By combining the signals, a dress start signal from which chattering has been removed can be obtained. Then, by using such a push button type switch as a start switch, an inching operation at the time of pre-pressurization can be facilitated as described later.
[0043]
Next, when the input signal to the Schmitt trigger inverter 54 (the output signal of the logic circuit 35) changes from “L” to “H”, the output of the activation signal generation circuit 32 is inverted by the clock input of the FF circuit 53. Therefore, as shown in FIGS. 10 (a) and 10 (b), by pushing down the dress start switch 5 to instruct the start of the dress (pressing instruction), the chattering prevention circuit 31 outputs the dress start signals S5a and S5b. You. Assuming that the block signal S10 from the malfunction prevention circuit 42 is “L”, the output of the NOR gate circuit 55 becomes the Q output of the FF circuit 53 because the dress start signal S5a from the chattering prevention circuit 31 becomes “H”. Irrespective of this, the signal becomes "L" and the start signal S6, which is the output of the NOR gate circuit 56, becomes "H" as shown in FIG.
[0044]
Therefore, as will be described later, when the hold command circuit 34 elapses a predetermined first set time (pre-pressurization time) t2 from the rise of the start signal S6 as shown in FIG. A hold command signal S8 which becomes "H" when a predetermined time (a time until the dressing start switch 5 is depressed again and the starting signal S6 becomes "L") has elapsed after the first set time has elapsed. Output. Then, until the pre-pressurization time t2 elapses, the output of the logic circuit 35 is maintained at “L”, so that the output of the FF circuit 53 is not inverted, and FIG. As shown by the broken line, the activation signal S6 becomes "H" every time the dress start signal S5a from the chattering prevention circuit 31 becomes "H".
[0045]
In this manner, the pressing / non-pressing is switched by repeatedly pressing and releasing the pressing of the dress activation switch 5 until the pre-pressurization time as the first set time elapses after pressing the dress activation switch 5. The dressing operation can be controlled (inching operation), and the dresser body 2 can be positioned so that the dresser main body 2 fits well with the electrode tips 1a and 1b.
[0046]
Then, when the pre-pressurizing time t2 has elapsed while the dress start switch 5 is kept pressed, the hold command signal S8 changes from "H" to "L". At this time, the dressing signal S8 changes as shown in FIG. Since the activation signal S5b is “L”, the output of the logic circuit 35 changes from “L” to “H”, a clock is input to the FF circuit 53, and the Q output of the FF circuit 53 becomes “H”. . Therefore, even if the dress start switch 5 is subsequently released from being depressed and the dress start signal S5a of the chattering prevention circuit 31 becomes “L”, the output of the NOR gate circuit 55 is held at “H”, and the NOR gate The start signal S6 output from the circuit 56 is also kept at "H".
[0047]
Therefore, after the pre-pressurization time t2, after the main pressurization time, even if the user releases the hand from the dress start-up switch 5 and releases the depression, the start-up signal S6 of the start-up signal generation circuit 32 is held and the electrode chip is held. Since the pressure of the dresser main body 2 by 1a and 1b is maintained, it is possible to concentrate on the dressing operation, and the workability is improved.
[0048]
Thereafter, by pushing down the dress start switch 5 again in this state, a clock is input to the FF circuit 53, the Q output thereof becomes “L”, and the start signal S6 from the NOR gate circuit 56 becomes “L”. That is, the start signal S6 is not output.
[0049]
Next, when the timing generation circuit 33 receives the activation signal S6 from the activation signal generation circuit 32 as shown in FIG. 11A (turns to “H”), as shown in FIG. The pre-pressing mono-multi 63 outputs a signal S12 that becomes "L" for a predetermined time (pre-pressing time t2) determined according to the values of the variable resistor VR1, the resistor R5, and the capacitor C3. When the signal S12 of 63 rises to "H", as shown in FIG. 3C, a predetermined time (main pressurization) determined from the main pressurizing mono-multi 64 according to the values of the variable resistor VR2, the resistor R6 and the capacitor C4. The signal S14, which is the inverted Q output that becomes “L” for the time t3), is output.
[0050]
Here, it is necessary to reset the pre-pressurizing mono-multi 63 and the main pressurizing mono-multi 64 when the starting signal is no longer input. Therefore, the starting signal S6 is input to the CLR terminals of the mono-multis 63 and 64. There must be.
However, when the start signal S6 is input to the CLR terminals of the pre-pressurizing mono-multi 63 and the main pressurizing mono-multi 64 as described above, the inverted Q output (signal S12) of the pre-pressing mono-multi 63 is directly used for the main pressurizing. When inputting to the mono-multi 64, that is, when trying to generate a timing corresponding to a predetermined pattern by combining two mono-multis simply serving as a timer, as shown in FIG. Since the delay time Δt1 occurs between the time when the start signal S6 is input and the time when the inverted Q output of the pre-pressurizing mono-multi 63 becomes “L”, the same figure is applied when the start signal S6 is input. As shown by a broken line in (c), the inconvenience occurs that the main mono-multi 64 for pressurization also operates.
[0051]
Therefore, in the present embodiment, by providing an AND circuit 65 which performs an AND operation between the start signal S6 and the inverted Q output (signal S12) of the pre-pressurizing mono-multi 63, the pre-loading is performed when the start signal S6 is "H". When the inverted Q output of the pressure mono-multi 63 changes from “L” to “H”, the main operation of the pressure mono-multi 64 is started to prevent malfunction due to a transient effect.
[0052]
Further, in the timing generation circuit 33, the inverted Q output of the pre-pressurizing mono-multi 63, the inverted Q output of the main pressurizing mono-multi 64 and the output of the AND circuit 66 which inputs the start signal S6, and the main pressurizing mono-multi 64 Is output to a hold command circuit 34 for generating a hold signal S8.
[0053]
In this case, when the start signal S6 is directly input to the AND circuit 66 and the AND circuit 65, when the start signal S6 is input from the hold command circuit 34 due to the above-described transient effect, as shown by a broken line in FIG. The output of the AND circuit 66 becomes "H" (the output of the AND circuit 65 is also the same), and one pulse is output from the hold command circuit 34 as the hold command signal S8 as shown by the broken line in FIG. As described in the start signal generation circuit 32, the clock signal is input to the FF circuit 53, and the start signal S6 enters a hold state. As a result, not only the inching operation during the pre-pressurizing time becomes impossible, but also the mono-multis 63 and 64 of the timing generation circuit 33 cannot be reset even if the dress start switch 5 is pressed thereafter.
[0054]
Therefore, the start signal S6 is not directly input to the AND circuit 66 and the AND circuit 65, but an integration circuit 67 is provided and an output obtained by integrating the start signal S6 is input to the AND circuit 66 and the AND circuit 65. (Signal S13) does not become "H" until the inverted Q output of the mono-multi 63 becomes "L" as shown in FIG. 11F, so that the hold command is issued during the delay time due to the transient effect. The output of the signal S8 can be prevented.
[0055]
Next, referring to FIG. 6, while the signal S12 from the pre-pressurizing mono-multi 63 is “L”, the chip coupler pressure setting circuit 37 turns on the photocoupler 71 of the interface circuit 36 and sets the resistor R9, A voltage signal corresponding to the resistance value determined by R10 and the variable resistor VR3 is supplied to the photocoupler 72 while the signal S14 from the pressurizing mono-multi 64 is “L”, and the resistors R9 and R11 and the variable resistor VR4 are turned on. While the signal S16 (inverted signal of FIG. 11E) from the Schmitt trigger inverter 68 is “L”, the photocoupler 73 is turned on and the resistors R9, R12 and A voltage signal corresponding to the resistance value determined by the variable resistor VR5 is output to the electro-pneumatic proportional valve 20 as a pressing force level setting signal S2, and the dressing by the electrode tips 1a and 1b is performed. Setting the pressure of the main body 2.
[0056]
Therefore, by adjusting the variable resistors VR3 to VR5, it is possible to set the pressing force of the pre-pressing, the pressing force of the main pressing, and the pressing force after the main pressing (finish pressure). In this case, by using the photocoupler and the diode array to generate one output signal as described above, the occupied space on the board can be reduced as compared with the case where a switching relay is used, and a combination of a resistor and a variable resistor can be used. By adjusting, the adjustment range can be widened.
[0057]
The welding pressure setting circuit 44 turns on the photocoupler 74 of the interface circuit 43 when the activation signal S6 is not input (at “L”), that is, at the time of “welding”. From the line selected at 75, voltage signals determined according to the resistance values of the variable resistors VR6 to VR8 and the resistor R15 are output to the electropneumatic proportional valve 20 as the pressure level setting signal S2 ', respectively, and are applied to the electrode tips 1a and 1b. Set the pressure on the base metal to be welded. Therefore, at the time of welding, the welding pressure can be selected by the rotary switch 75.
[0058]
Next, returning to FIG. 4, when the dress / weld changeover switch 40 is set to the dress side, the transistor TR1 of the interlock receiving circuit 41 is turned on, the output signal S11 becomes “H”, and the relay 57 is turned on. Power is supplied to As a result, as shown in FIG. 7, the contacts CR1 and CR2 of the relay 57 are closed, and the contacts CR3 to CR5 are opened to cut off the power supply to the welding timer 6 and cut off the power supply from the solenoid valve terminal of the welding timer 6. In this state, the welding timer 6 does not operate during dressing.
[0059]
Further, since the output signal S11 of the interlock receiving circuit 41 becomes “H”, the blocking signal S10 output from the malfunction preventing circuit 42 becomes “L” and the blocking signal S9 becomes “H”. As described above, the start signal S6 can be output from the start signal generation circuit 32, and when the start signal S6 is output from the start signal generation circuit 32, the pressurizing valve switching circuit 38 shown in FIG. The power supply path to the solenoid valve 21 is closed.
[0060]
By the way, at this time, if the output of the dress / weld changeover switch 40 is directly input to the respective CLR terminals of the FF circuit 51 of the chattering prevention circuit 31 and the FF circuit 53 of the start-up signal generation circuit 32, the dress / welding is performed. When the controller 3 is turned on with the changeover switch 40 set to the dress side, the dress is executed one cycle before the CLR terminals of the FF circuits 51 and 53 become “H” and the dress start switch 5 is pressed. Will be.
[0061]
Therefore, by providing the malfunction prevention circuit 42 with a combination of a delay circuit 59 including a resistor R4 and a capacitor C2 and two Schmitt trigger inverters, the controller 3 is controlled in a state where the dress / weld changeover switch 40 is set to the dress side. When the power is turned on, a stop signal S9 which becomes “H” after a predetermined delay time has elapsed is output, so that the FF circuit 51 of the chattering prevention circuit 31 and the FF circuit 53 of the start signal generation circuit 32 need to be reset sufficiently. An "L" input is given to the CLR terminal of each FF circuit 51, 53 to prevent malfunction.
[0062]
On the other hand, when the dress / weld changeover switch 40 is set to the welding side, the transistor TR1 of the interlock receiving circuit 41 is turned off, the output signal S11 becomes "L", and the blocking signal S9 of the malfunction preventing circuit 42 becomes "L". L, the blocking signal S10 becomes "H". Therefore, even if the dress start switch 5 is pressed, the dress start signal S5 is not output because the AND circuit 52 of the chattering prevention circuit 51 is closed. Since one input of the NOR gate circuit 56 of the generation circuit 32 is "H", the output thereof becomes "L" regardless of the other input, and the start signal S6 is not output.
[0063]
Therefore, a hand dress operation procedure using the controller 3 will be described with reference to FIG. 12 as well. After the power of the controller 3 is turned on, the dress / weld changeover switch 40 is set to the “dress” side. As described above, the welding timer 6 becomes inoperable and the operation of the welding machine cannot be performed.
[0064]
In this state, when the dresser main body 2 is set on the electrode tip 1b of the lower gun 1B of the welding machine and the dress start switch 5 is pressed, as shown in FIG. Command) is input to the chattering prevention circuit 31 of the controller 3, the dressing start signal S5 is output from the chattering prevention circuit 31, and the start signal S6 is output from the start signal generation circuit 32, as shown in FIG. Then, the pressurizing solenoid valve 21 is operated by the pressurizing valve switching circuit 38 to open the air supply path, so that the upper gun 1A of the welding machine descends, and the dresser body 2 is sandwiched between the electrode tips 1a and 1b. Pressed. At this time, according to the signal S12 from the timing generation circuit 33, the tip pressure setting circuit 37 sets the pressing force (tip dress pressure) to the pressing force level setting signal S2 for setting the pressing force at the time of pre-pressurization. Since the pressure is output to the proportional valve 21, the pressure is set to the prepressurizing pressure.
[0065]
In this case, when a problem such as the alignment between the electrode tips 1a and 1b and the dresser body 2 occurs, the inching operation can be performed at the time of pre-pressing as described above. As a result, the upper gun 1A of the welding machine is opened and pressurization of the dresser main body 2 by the electrode tips 1a and 1b is stopped, so that the dressing start switch 5 can be pressed again to perform positioning.
[0066]
Here, as shown in FIG. 12C, the pressing force of the main pressurization is set higher than the prepressurization and the pressing force of the finishing pressure is set lower than the prepressurization as shown in FIG. When the dressing operation is performed by repeatedly pressing the arm 11 of the dresser body 2 while pressing the button, the user feels light during the initial pre-pressurization and heavier when shifting to the main pressurization on the way. Then, when the dress start switch 5 is released, the self-holding state is established as described above, so that the user can concentrate on the dressing work.
[0067]
Further, if the dressing operation is continued, the repetition work becomes lighter when shifting to the finishing pressure. Therefore, after performing the dressing operation several times, pressing the dress start switch 5 opens the upper gun 1A to open the dressing. Work is completed.
[0068]
In the above embodiment, an example in which the timing generation device according to the present invention is applied to a controller of a hand dresser has been described. However, a first signal indicating that a first set time has elapsed since an input signal was input. The timing generation device according to the present invention can be similarly applied to any device that requires a second signal indicating that the second set time has elapsed since the first set time has elapsed. However, the target device is not limited.
[0069]
【The invention's effect】
As described above, according to the timing generation device of the first aspect, the input signal is input to the input terminal and the clear terminal of the first monostable multivibrator for setting the first set time, respectively. A first signal and an input signal obtained from an output terminal of the monostable multivibrator are input to an AND circuit, and an output signal of the AND circuit is input to a second monostable multivibrator for setting a second set time. And the clear terminal, respectively, to obtain the second signal from the output terminal of the second monostable multivibrator. Therefore, when the input signal is no longer input, the two monostable multivibrators can be reset. In addition, it can generate and output accurate timing signals without being affected by the transient effect of the monostable multivibrator. Kill the timing generation device can be obtained.
[0070]
According to a second aspect of the present invention, in the timing generating apparatus of the first aspect, the first and second monostable multivibrators are provided with setting time adjusting means for variably setting the first and second setting times. Therefore, the first set time and the second set time can be adjusted within a required range.
[Brief description of the drawings]
FIG. 1 is an overall system configuration diagram showing one embodiment of the present invention. FIG. 2 is an exploded perspective view of a hand dresser main body. FIG. 3 is a block diagram of a controller. FIG. 4 is a chattering prevention circuit and a start signal generation circuit in FIG. FIG. 5 is a circuit diagram showing details of an interlock receiving circuit and a malfunction prevention circuit. FIG. 5 is a circuit diagram showing details of a timing generation circuit in FIG. 3. FIG. 6 is a chip dress pressure setting circuit, a welding pressure setting circuit, etc. in FIG. FIG. 7 is a circuit diagram showing details of a pressurizing valve switching circuit and the like in FIG. 3; FIG. 8 is an external view of a controller; FIG. 9 is a timing chart for explaining the operation of the chattering prevention circuit; FIG. 11 is a timing chart for explaining the operation of the start signal generating circuit and the holding means. FIG. 11 is a timing chart for explaining the operation of the timing generating circuit and the holding means. Explanatory view for explaining the work DESCRIPTION OF SYMBOLS
1A: Upper gun, 1B: Lower gun, 1a, 1b: Electrode chip, 2: Dresser body, 3: Controller, 4: Pressurizing drive system, 5: Dress start switch, 6: Weld timer, 20: Static control valve , 21 ... Pressure solenoid valve, 31 ... Chattering prevention circuit, 32 ... Start signal generation circuit, 33 ... Timing generation circuit, 34 ... Hold command circuit, 35 ... Logic circuit, 37 ... Tip dress pressure setting circuit, 38 ... Pressure Valve switching circuit, 41: interlock receiving circuit, 42: malfunction prevention circuit, 44: welding pressure setting circuit.

Claims (2)

In a timing generation device used for a manually operated hand dresser, the timing generation device inputs an input signal to an input terminal and a clear terminal of a first monostable multivibrator for setting a first set time. A first signal obtained from the inverted output terminal of the monostable multivibrator and indicating that a first set time has elapsed since the input signal was input , and the input signal are integrated by an integrating circuit comprising a resistor and a capacitor. and integrating the output entered to the aND circuit, the output of the aND circuit is inputted to the input terminal and the clear terminal of the second monostable multivibrator configured to set the second set time, the second single the indicates that the non-inverting output terminal of the astable multivibrator, said second set time from when the first set time has elapsed has elapsed The timing generator and wherein the obtaining of the signal. 2. The timing generation device according to claim 1, wherein said first and second monostable multivibrators are provided with a set time adjusting means for variably setting said first and second set times. Generator.

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