JP2009211461A - Numerical controlling device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a numerical controlling device for machine tools which reduces power consumption and actually achieves energy-saving in the whole device and restraint of heat generation. <P>SOLUTION: The numerical controlling device is provided with: a power source 2 for signals; a switch SW whose one side is connected to the power source 2 for signals and whose other side is connected to a ground potential and which generates operation signals corresponding to operations of an operation switch; a control circuit 10 which sets an energization time segment for substantially supplying currents from the power source 2 for signals to the switch SW and a non-energization time segment for substantially stopping the supply of currents from the power source 2 for signals to the switch SW and executes energization processing to each segment; a transistor TR; and a load resistor R. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a numerical control apparatus that controls operation of a machine tool using numerical information, and more particularly to a numerical control apparatus that includes a switch circuit.

  In general, a numerical control device (microcomputer) of a machine tool includes a switch circuit for inputting various signals from various operation switches and sensors. Usually, DC24V is often used as the power supply voltage of the switch circuit. At this time, since it is necessary to pass a certain current (generally 5 to 20 mA) through the contact portion of the switch or the like, for example, in order to pass a current of 10 mA, 2.4 KΩ is used as a load resistance of the switch circuit. Will be used. In this case, the power consumption of one resistor is 0.24 w. For example, when there are 50 circuits, 12 W of power is consumed. As a result, there is a problem that power consumption increases and heat generation increases accordingly.

As a conventional technique for solving such a problem, for example, there is one described in Patent Document 1. In this prior art, one end of each of the plurality of switches is connected to a port of the numerical control device, and the other end is collectively connected to an installation potential through a resistor, and the numerical control device connects to the plurality of switches through the port to a predetermined potential. Is detected, the ON / OFF state of each operating device is identified by detecting the potential of each port. By adopting such a configuration, the resistance required for each port is not required, so that the current that flows when the operating device is in the ON state can be reduced, resulting in a reduction in power consumption. Yes.
JP-A-6-4193

  Although not specifically described in Patent Document 1, an A / D converter is required to realize the configuration of the conventional technique. Further, in the above prior art, since the numerical control device detects the stray capacitance between lines formed between each port and the ground, there is a weak point that it is vulnerable to noise. Therefore, it cannot be said to be a realistic configuration for reducing power consumption in a numerical control device of a machine tool.

  An object of the present invention is to provide a numerical control device that can reduce power consumption, and can practically realize energy saving and suppression of heat generation in the entire device.

  In order to achieve the above object, a numerical control device according to a first aspect of the present invention includes a switch, a signal power source that supplies power to the switch, and a resistor that is connected to the switch and restricts a current flowing through the switch. In the numerical controller having a switch circuit in which the signal power source is connected to one of the switches and the other is connected to the ground potential, the switch circuit supplies a voltage from the signal power source to the switch. And a switching means for switching whether or not, and when the voltage is supplied from the signal power source to the switch by the switching means, a storage means for storing an operating state of the switch is provided.

  The numerical control device according to the first aspect of the present invention includes a switch circuit having switching means for switching whether or not voltage is supplied from the signal power source to the switch, and when the voltage is supplied from the signal power source to the switch by the switching means, Storage means for storing the operating state is provided. When a voltage is supplied from the signal power source to the switch by the switching means, a current flows from the signal power source to the ground potential via the switch, and the switch is energized. Accordingly, the switch can output an operation signal corresponding to the on / off operation of the switch. On the other hand, when the voltage supply from the signal power supply to the switch is stopped by the switching means, the switch is not energized and cannot output an operation signal, but the switch operation at the time of voltage supply stored in the storage means Based on the state, it becomes possible to output an operation signal corresponding to the switch operation at the time of voltage supply.

  Thus, an operation signal corresponding to the on / off operation of the switch can be output without always supplying a voltage to the switch. As a result, it is possible to shorten the energization time to the switch as much as possible, and to energize only when the operation signal output function of the switch is necessary, and not energize otherwise. As a result, the power consumed by energizing the switch can be reduced, and energy saving and suppression of heat generation in the entire apparatus can be realized practically.

  According to a second aspect of the present invention, in the first invention, the switching means supplies the voltage from the signal power source to the switch after supplying the voltage from the signal power source to the switch for a predetermined time. It is characterized by repeating stopping for a predetermined time.

  In the numerical control device according to the second aspect of the present invention, the switching unit repeatedly supplies the voltage from the signal power source to the switch for a predetermined time and then stops supplying the voltage from the signal power source to the switch for the predetermined time. Thereby, the energization time to the switch can be shortened as much as possible by appropriately determining the length ratio of the non-energization time to the energization time. As a result, power consumption can be reliably reduced.

  The numerical control device according to a third aspect of the present invention is the numerical control device according to the second aspect, further comprising a plurality of the switch circuits, wherein the time for supplying the voltage from the signal power source to the switch by the switching means of each switch circuit may overlap. Control means for controlling each of the switching means is provided.

  The numerical control apparatus according to the third aspect of the present invention includes a plurality of switch circuits and control means. The control means controls the switching means of each switch circuit so that the time for supplying the voltage from the signal power source to the switch in each switch circuit does not overlap. Thereby, increase of a peak current can be suppressed and the power supply used for a machine tool can be made small.

  According to a fourth aspect of the present invention, in the third aspect, the control means controls the switching means based on information stored in the storage means.

  In the numerical control apparatus according to the fourth aspect of the present invention, the control means controls the switching means based on the information stored in the storage means. Thus, if the operation state of the predetermined switch is stored in the storage means, the voltage supply from the signal power supply to the switch is stopped by the switching means when the predetermined switch does not have to operate substantially. It becomes possible to stop energization to the switch. In this way, power consumption can be reliably reduced by preventing energization except when the signal output function of the switch is required.

  The numerical control device according to a fifth aspect of the present invention is the numerical control device according to the fourth aspect, wherein the switches of the plurality of switch circuits are constituted by an automatic operation start switch for executing automatic operation of the machine tool and a stop switch for stopping the automatic operation, If the control means stores in the storage means that the automatic operation start switch has been operated, the switching means of the switch circuit of the automatic operation start switch is switched from the signal power source to the automatic operation. If the control is performed so that no voltage is supplied to the start switch, and the storage means stores that the stop switch has been operated, the switching means of the switch circuit of the stop switch is removed from the signal power source. Control is performed so that no voltage is supplied to the stop switch.

  In the numerical control device according to the fifth aspect of the present invention, when the automatic operation start switch is operated and operated in the machine tool, the operation switch is not normally operated continuously, and the stop switch may be utilized. Therefore, it is possible to stop the voltage supply to the start switch and stop the energization to the start switch. Similarly, when the stop switch is operated and operated, the stop switch is not normally operated continuously, and it is only necessary to utilize the automatic operation start switch. It can stop and stop energizing the stop switch. In this way, power consumption can be reliably reduced by preventing energization except when the signal output function of the switch is required.

  According to a sixth aspect of the present invention, in any one of the first to fifth aspects, the switching means includes a transistor that switches an output voltage in accordance with an input signal.

  When the transistor switches the output voltage in accordance with the input signal from the control means, the current value output to the switch by the load resistor to which the transistor output voltage is input changes. Thereby, the energization amount to the switch can be controlled to increase or decrease by controlling the transistor by the control means.

  According to the present invention, power consumption can be reduced, and energy saving and suppression of heat generation in the entire apparatus can be realized practically.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In this specification, for each signal, the signal corresponding to High is described as “H”, and the signal corresponding to Low is described as “L”.

  FIG. 1 is a block diagram showing a functional configuration of the numerical control apparatus according to the present embodiment.

  The numerical control device 1 of the present embodiment controls the operation of a machine tool (not shown) using numerical information. The numerical control device 1 includes a signal power source 2, a switch SW having one side connected to the signal power source 2 and the other side connected to a ground potential, and outputting an operation signal corresponding to an on / off operation, A transistor TR (switching means) which is located in a circuit between the power supply for signal 2 and the switch SW and switches the output voltage of the signal power supply 2 in accordance with a control signal (input signal) from the control circuit 10 described later; A load resistor R (resistance) provided in a circuit between TR and the switch SW, a control circuit 10 that performs increase / decrease control of the energization amount to the switch SW by the transistor TR and the load resistor R, and a plurality of outputs output by the switch SW Of the operation signals ("L" corresponding to switch ON (low input voltage) and "H" corresponding to switch OFF (high input voltage)) are compared, and corresponding comparison result information ( Based on the control of the control circuit 10, the output of the comparison result information from the input voltage comparison circuit CC is held based on the control of the input voltage comparison circuit CC that outputs the operation signal “L” or “H”). And a flip-flop circuit FF (storage means).

  The numerical control device 1 includes a signal power supply 2, a transistor TR, a load resistor R, a control circuit 10, an input voltage comparison circuit CC, and a flip-flop circuit FF, excluding the switch SW, on the control board 20.

  The switch SW outputs the operation signal “L” to the input voltage comparison circuit CC in the closed state based on energization from the signal power source 2 to the ground potential. On the other hand, based on the deenergization from the signal power source 2 to the ground potential, the operation signal “H” is output to the input voltage comparison circuit CC in the open state.

  The control circuit 10 (control means) includes a CPU 11, a ROM 12, a RAM 13, first to third timers T1, T2, T3 (indicated by “timers 1, 2, 3” in the figure), and an input / output interface (in the figure, 14 (indicated by “I / O”). The CPU 11 controls the overall operation of the machine tool by executing the machine tool control software stored in the ROM 12 while accessing (referring to or writing to) the RAM 13.

  The CPU 11 outputs a control signal to the transistor TR via the input / output interface 14. Based on the control signal from the CPU 11, the transistor TR switches whether to supply a voltage from the signal power source 2 to the switch SW. Specifically, when a transistor base signal (hereinafter referred to as “TR base signal”) “L” is input from the CPU 11, the transistor TR supplies a voltage from the signal power source 2 to the switch SW to the switch SW. When the TR base signal “H” is input from the CPU 11, the voltage supply from the signal power supply 2 to the switch SW is stopped and the power supply to the switch SW is stopped.

  In this specification, “to energize” refers to energization (voltage, current) of an amount substantially necessary for the functioning of the corresponding switch SW, and “stops energization”. In addition, the energization (voltage, current) is not limited to 0, and includes a small energization (voltage, current) in which the corresponding switch SW does not substantially function.

  Further, the CPU 11 outputs a flip-flop clock signal (hereinafter referred to as “FF clock signal”) “H” or “L” to the flip-flop circuit FF via the input / output interface 14. When the flip-flop circuit FF receives the FF clock signal “H” from the CPU 11, the comparison result information from the input voltage comparison circuit CC at the rising edge (whether the operation signal output from the switch SW is “L”). Or is it “H”) and outputs it to the input / output interface 14. On the other hand, when the flip-flop circuit FF receives the FF clock signal “L” from the CPU 11, the comparison result from the input voltage comparison circuit CC at the rising edge when the FF clock signal “H” is input before that. The information is held as it is and output to the input / output interface 14. The CPU 11 acquires the comparison result information output from the flip-flop circuit FF via the input / output interface 14.

  The first timer T1 is a timer for measuring the output time (pulse time) of the FF clock signal “H” output from the CPU 11 to the flip-flop circuit FF via the input / output interface 14. The second timer T2 measures the waiting time from when the CPU 11 outputs the TR base signal “L” to the transistor TR via the input / output interface 14 until the next FF clock signal is output to the flip-flop circuit FF. It is a timer to do. The third timer T3 includes a transistor TR from when the CPU 11 outputs the TR base signal “H” to the transistor TR through the input / output interface 14 until the next time the TR base signal “L” is output to the transistor TR. It is a timer for measuring the switching waiting time.

  In FIG. 1, for simplicity of explanation, the switch circuit (switch SW and corresponding signal power source 2, transistor TR, load resistor R, input voltage comparison circuit CC, flip-flop circuit FF, etc.) is 1 Although only the series is shown, in general, a machine tool is provided with a plurality of switch circuits for inputting various signals from a plurality of operating devices (various operation switches, sensors, etc.). May be.

  FIG. 2 is a flowchart showing the control contents executed by the CPU 11 of the control circuit 10.

  First, in step S10, the CPU 11 reads timer set times Tc, Tf, Tw from an appropriate storage unit (for example, the RAM 13). The set time Tc is used for timing by the first timer T1, and is an output time of the FF clock signal “H” set in advance to a predetermined value. The set time Tf is used by the second timer T2, and is a time constant of a noise removal filter (not shown) included in the input voltage comparison circuit CC that is set in advance to a predetermined value. The set time Tw is used for timing by the third timer T3, and is a switching wait time of the transistor TR set in advance to a predetermined value (see FIG. 4 described later).

  In the next step S20, the CPU 11 clears the time t3 of the third timer T3 to 0 and starts time measurement with the third timer T3.

  In the next step S30, the CPU 11 determines whether or not the time t3 of the third timer T3 is equal to or longer than the set time Tw. When the time t3 of the third timer T3 becomes equal to or longer than the set time Tw, it is considered that the switching time of the transistor TR has elapsed, and the process proceeds to the next step S100.

  In step S100, the CPU 11 performs an input confirmation subroutine (see FIG. 3 described later for details) for inputting comparison result information corresponding to the operation signal of the switch SW.

  In the next step S40, the CPU 11 determines whether or not to end the process (for example, whether or not the power of the machine tool or the numerical control device 1 is turned off). If the process is not terminated, the process returns to the previous step S20 and the same procedure is repeated. On the other hand, when the process is terminated, this flow is terminated.

  The flowchart is not intended to limit the present invention to the procedure shown in the flowchart, and the procedure may be added / deleted / changed without departing from the spirit and technical idea of the invention.

  FIG. 3 is a flowchart showing the detailed procedure of the input confirmation subroutine (step S100).

  First, in step S <b> 110, the CPU 11 outputs a TR base signal “L” to the transistor TR via the input / output interface 14. As a result, the transistor TR switches the output voltage of the signal power source 2 so as to energize the switch SW.

  In the next step S120, the CPU 11 clears the time t2 counted by the second timer T2 to 0 and starts timing by the second timer T2.

  In the next step S130, the CPU 11 determines whether or not the time t2 of the second timer T2 is equal to or longer than the set time Tf. When the time t2 of the second timer T2 becomes equal to or longer than the set time Tf, it is assumed that the second timer T2 is not affected by the noise removal filter of the input voltage comparison circuit CC, and the process proceeds to the next step S140.

  In step S <b> 140, the CPU 11 outputs the FF clock signal “H” to the flip-flop circuit FF via the input / output interface 14. Thereby, the flip-flop circuit FF holds the comparison result information (whether the operation signal from the switch SW is “L” or “H”) from the input voltage comparison circuit CC at the rising edge of the FF clock signal. And output to the input / output interface 14.

  In the next step S150, the CPU 11 clears the time t1 of the first timer T1 to 0, and starts counting with the first timer T1.

  In the next step S160, the CPU 11 determines whether or not the time t1 of the first timer T1 is equal to or longer than the set time Tc. When the time t1 of the first timer T1 becomes equal to or longer than the set time Tc, it is considered that the output time of the FF clock signal “H” has elapsed, and the process proceeds to the next step S170.

  In step S <b> 170, the CPU 11 outputs the FF clock signal “L” to the flip-flop circuit FF via the input / output interface 14. Thereby, the flip-flop circuit FF holds the comparison result information from the input voltage comparison circuit CC at the rising edge when the FF clock signal “H” is input before and outputs it to the input / output interface 14. Further, the CPU 11 outputs a TR base signal “H” to the transistor TR via the input / output interface 14. Thereby, the transistor TR switches the output voltage of the signal power source 2 so as to stop energization of the switch SW. This subroutine is completed above.

  The flowchart is not intended to limit the present invention to the procedure shown in the flowchart, and the procedure may be added / deleted / changed without departing from the spirit and technical idea of the invention.

  FIG. 4 is a time chart showing the output state of the TR base signal and the FF clock signal from the CPU 11 under the control described above.

  When the time t3 measured by the third timer T3 reaches the set time Tw (see step S30 in FIG. 2), the CPU 11 outputs the TR base signal “L” (see step S110 in FIG. 3). When the time t2 measured by the two timers T2 reaches the set time Tf (see step S130), the FF clock signal “H” is output (see step S140), and the time measured by the first timer T1 from that point in time t1 is the set time. When Tc is reached (see step S160), the FF clock signal “L” is output and the TR base signal “H” is output (see step S170). When the time t3 measured by the third timer T3 from that time reaches the set time Tw, the TR base signal “L” is output again, and the same procedure is repeated thereafter.

  Therefore, for example, when Tf + Tc + Tw = 10 ms, when Tw, which is the non-energization time, is set to 9 ms, Tf + Tc, which is the energization time, is 1 ms, so that the power consumption can be reduced to 1/10. Become.

  The numerical control device 1 of the embodiment described above includes a switch circuit having a transistor TR that switches whether or not a voltage is supplied from the signal power source 2 to the switch SW, and a voltage from the signal power source 2 to the switch SW by the transistor TR. In the case of supplying, it has a flip-flop circuit FF that holds the output of comparison result information from the input voltage comparison circuit CC representing the operating state of the switch SW. When a voltage is supplied from the signal power supply 2 to the switch SW by the transistor TR, a current flows from the signal power supply 2 to the ground potential via the switch SW, and the switch SW is energized. Thereby, the switch SW can output an operation signal corresponding to the on / off operation of the switch. On the other hand, when the voltage supply from the signal power source 2 to the switch SW is stopped by the transistor TR, the switch SW is not energized and cannot output an operation signal, but the input voltage held by the flip-flop circuit FF Comparison result information from the comparison circuit CC can be output to the control circuit 10.

  Accordingly, an operation signal corresponding to the on / off operation of the switch SW can be output without always supplying a voltage to the switch SW. As a result, the energization time to the switch SW can be shortened as much as possible, or energization can be performed only when the operation signal output function of the switch SW is necessary, and the energization can be prevented from being performed otherwise. As a result, the power consumed by energizing the switch SW can be reduced, and energy saving and suppression of heat generation in the entire apparatus can be realized practically.

  In the present embodiment, in particular, after the transistor TR supplies the voltage from the signal power source 2 to the switch SW for a predetermined time, the supply of the voltage from the signal power source 2 to the switch SW is repeatedly stopped for a predetermined time. Thereby, the energization time to switch SW can be shortened as much as possible by appropriately determining the length ratio of the non-energization time to switch SW to the energization time. As a result, power consumption can be reliably reduced.

  The present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit and technical idea of the present invention. Hereinafter, such modifications will be described in order.

(1) When the voltage switching timing is shifted Although not particularly considered in the above embodiment, the peak current is increased by shifting the timing so that the time for supplying the voltage by the transistor does not overlap for a plurality of switch circuits. May be suppressed.

  FIG. 5 is a block diagram illustrating a functional configuration of the numerical control device of the machine tool according to the present modification, and corresponds to FIG. 1 described above. The same parts as those in FIG.

  The numerical control apparatus 1A of the present modification includes a plurality of (three in this example) switch circuits corresponding to a plurality (three in this example) of switches SW1, SW2, and SW3. The switch circuit corresponding to each switch SW1, SW2, SW3 is located in the signal power source 2 and the circuit between the signal power source 2 and the switches SW1, SW2, SW3, respectively, as in the above-described embodiment. A transistor TR1, TR2, TR3 that switches the output voltage of the signal power source 2 in response to a control signal (input signal) from the control circuit 10A described later, and these transistors TR1, TR2, TR3 and switches SW1, SW2, SW3 Input voltage comparison circuit CC1, which compares the values of a plurality of operation signals output from switches SW1, SW2, SW3 and outputs corresponding comparison result information respectively, with load resistors R1, R2, R3 provided in the circuit between them Based on the control of CC2 and CC3 and the control circuit 10A, the ratio from the input voltage comparison circuits CC1, CC2 and CC3 Results flip-flop circuits FF1 to hold the output of information respectively, FF2, and a FF3 (storage means). Further, the numerical controller 1A controls the control circuit 10A (for shifting the timing so that the time for supplying the voltage from the signal power source 2 to the switches SW1, SW2, SW3 by the transistors TR1, TR2, TR3 does not overlap. Control means). Since the configuration of the control circuit 10A is the same as that of the control circuit 10 described above, description thereof is omitted.

  FIG. 6 is a flowchart showing the control contents executed by the CPU 11 of the control circuit 10A. In the following flow, the series n (n = 1, 2,...) Refers to a switch circuit corresponding to the switch SW (n).

  First, in step S210, the CPU 11 reads timer setting times Tc, Tf, Tw2 from an appropriate storage unit (for example, the RAM 13). The set times Tc and Tf are the same as in the above-described embodiment. The set time Tw2 is used for timing by the third timer T3, and is set to a predetermined value in advance from the power supply OFF of the current series n transistor TR (eg TR1) to the next series n + 1 transistor TR (eg This is the switching waiting time until the power is turned on by TR2) (see FIG. 8 described later).

  In the next step S220, the CPU 11 clears n representing the number of series to 0.

  In the next step S230, the CPU 11 clears the time t3 measured by the third timer T3 to 0 and starts time measurement using the third timer T3.

  In the next step S240, the CPU 11 determines whether or not the measured time t3 of the third timer T3 is equal to or longer than the set time Tw2. When the time t3 of the third timer T3 becomes equal to or longer than the set time Tw2, it is considered that the switching time of the transistor TR has elapsed, and the process proceeds to the next step S250.

  In step S250, the CPU 11 adds 1 to n representing the number of series.

  In the next step S300, the CPU 11 performs an input confirmation subroutine (refer to FIG. 7 described later for details) for inputting comparison result information corresponding to the operation signal of the switch SW (n).

  In the next step S260, the CPU 11 determines whether or not to end the process (for example, whether or not the power of the machine tool or the numerical control device 1 is turned off). When the process is finished, this flow is finished. On the other hand, if the process is not terminated, the process proceeds to the next step S270.

  In step S270, it is determined whether or not the number of series n is nmax. nmax is the total number of series that the numerical control device of the machine tool has. For example, in this modification, nmax = 3 as shown in FIG. If n ≠ nmax, the process returns to the previous step S230 and the same procedure is repeated again. On the other hand, if n = nmax, the process returns to the previous step S220, the series number n is cleared to 0, and the same procedure is repeated again.

  The flowchart is not intended to limit the present invention to the procedure shown in the flowchart, and the procedure may be added / deleted / changed without departing from the spirit and technical idea of the invention.

  FIG. 7 is a flowchart showing the detailed procedure of the input confirmation subroutine (step S300).

  First, in step S <b> 310, the CPU 11 outputs a TR (n) base signal “L” to the transistor TR (n) via the input / output interface 14. Thereby, the transistor TR (n) switches the output voltage of the signal power source 2 so as to energize the switch SW (n).

  In the next step S320, the CPU 11 clears the time t2 of the second timer T2 to 0 and starts time measurement using the second timer T2.

  In the next step S330, the CPU 11 determines whether or not the time t2 of the second timer T2 is equal to or longer than the set time Tf. When the time t2 of the second timer T2 becomes equal to or longer than the set time Tf, the second timer T2 is regarded as not affected by the noise removal filter of the input voltage comparison circuit CC (n), and the process proceeds to the next step S340.

  In step S <b> 340, the CPU 11 outputs the FF (n) clock signal “H” to the flip-flop circuit FF (n) via the input / output interface 14. Thereby, the flip-flop circuit FF (n) has the comparison result information from the input voltage comparison circuit CC (n) at the rising edge of the FF (n) clock signal (the operation signal from the switch SW (n) is “L”. Whether it is “H” or “H”) and outputs it to the input / output interface 14.

  In the next step S350, the CPU 11 clears the time t1 of the first timer T1 to 0 and starts time measurement using the first timer T1.

  In the next step S360, the CPU 11 determines whether or not the time t1 of the first timer T1 is equal to or longer than the set time Tc. When the time t1 of the first timer T1 becomes equal to or longer than the set time Tc, it is considered that the output time of the FF (n) clock signal “H” has elapsed, and the process proceeds to the next step S370.

  In step S <b> 370, the CPU 11 outputs the FF (n) clock signal “L” to the flip-flop circuit FF (n) via the input / output interface 14. Thus, the flip-flop circuit FF (n) holds the comparison result information from the input voltage comparison circuit CC (n) at the rising edge when the FF (n) clock signal “H” is input before that. To the input / output interface 14. Further, the CPU 11 outputs a TR (n) base signal “H” to the transistor TR (n) via the input / output interface 14. As a result, the transistor TR (n) switches the output voltage of the signal power source 2 so as to stop energization of the switch SW (n). This subroutine is completed above.

  The flowchart is not intended to limit the present invention to the procedure shown in the flowchart, and the procedure may be added / deleted / changed without departing from the spirit and technical idea of the invention.

  FIG. 8 is a time chart showing the output state of the TR (n) base signal and FF (n) clock signal from the CPU 11 under the control described above.

  Similarly to FIG. 4, the CPU 11 outputs the TR (n) base signal “L” in the series n (see step S310 in FIG. 7), and the time t2 measured by the second timer T2 from that time is the set time. When Tf is reached (see step S330), the FF (n) clock signal “H” is output (see step S340), and when the time t1 counted by the first timer T1 from that time reaches the set time Tc (step S360). FF (n) clock signal “L” and TR (n) base signal “H” are output (see step S370). When the time t3 measured by the third timer T3 from that point in time reaches the set time Tw2, the TR (n + 1) base signal “L” is output in the next sequence n + 1, and then the same procedure as in the sequence n is repeated. .

  In this modification, in this way, the peak is obtained by appropriately shifting the timing so that the time for supplying the voltage to the switch SW (n) by the transistor TR (n) does not overlap in a plurality of series of switch circuits. An increase in current can be suppressed. As a result, the power source used for the machine tool can be reduced.

(2) When stopping the voltage supply to the switch according to the operating status of the machine tool By stopping the voltage supply to the switch that does not need to be confirmed according to the operating status (eg start / stop) of the machine tool The power may be saved.

  FIG. 9 is a block diagram illustrating a functional configuration of the numerical control device of the machine tool according to the present modification, and corresponds to FIG. 5 described above. The same parts as those in FIG.

  The numerical control apparatus 1B of this modification has a plurality of (two in this example) switch circuits corresponding to a plurality (two in this example) of switches SW1 and SW2. The switch SW1 is a start switch for executing automatic operation of the machine tool (hereinafter referred to as “start switch SW1”), and the switch SW2 is a stop switch for stopping automatic operation of the machine tool (hereinafter referred to as “stop switch SW2”). To describe). The switch circuits corresponding to the start / stop switches SW1 and SW2 are located in the signal power source 2 and the circuits between the signal power source 2 and the switches SW1 and SW2, respectively, as in the above-described embodiment. And transistors TR1 and TR2 for switching the output voltage of the signal power source 2 in response to a control signal (input signal) from the control circuit 10B, and a circuit between the transistors TR1 and TR2 and the start / stop switches SW1 and SW2. Load resistors R1 and R2 provided respectively are compared with input voltage comparison circuits CC1 and CC2 for comparing the values of a plurality of operation signals output by the start / stop switches SW1 and SW2 and outputting corresponding comparison result information, respectively. ing. Further, the numerical control device 1B includes a control circuit 10B (control means) that performs control to stop the voltage supply to the switch that does not need to be confirmed in accordance with the operation state (start / stop) of the machine tool. The configuration of the control circuit 10B is the same as that of the control circuit 10A described above except that the first to third timers T1, T2, and T3 are not provided.

  FIG. 10 is a flowchart showing the control contents executed by the CPU 11 of the control circuit 10B.

  First, in step S410, the CPU 11 determines whether or not a flag indicating that the machine tool is in operation is ON. If the flag is ON, the process proceeds to the next step S420.

  In step S420, the CPU 11 outputs the TR1 base signal “H” to the transistor TR1 via the input / output interface 14, and outputs the TR2 base signal “L” to the transistor TR2. Thus, the voltage supply to the start switch SW1 is stopped to invalidate the start switch SW1, and the power is supplied to the stop switch SW2 to enable the stop switch SW2.

  In the next step S430, the CPU 11 determines whether or not the stop switch SW2 has been operated based on the output of comparison result information from the input voltage comparison circuit CC2. When the comparison result information from the input voltage comparison circuit CC2 corresponds to “H” (the operation signal output from the stop switch SW2 is “H”), the stop switch SW2 is regarded as not being operated, Control proceeds to step S480, which will be described later. On the other hand, when the comparison result information from the input voltage comparison circuit CC2 corresponds to “L” (the operation signal output from the stop switch SW2 is “L”), it is considered that the stop switch SW2 has been operated, Next step S440 is entered.

  In step S440, the CPU 11 turns off a flag indicating that the machine tool is in operation. Thereafter, the process proceeds to step S480 described later.

  On the other hand, in the previous step S410, when the flag indicating that the machine tool is in operation is OFF, the CPU 11 proceeds to step S450.

  In step S450, the CPU 11 outputs the TR1 base signal “L” to the transistor TR1 through the input / output interface 14, and outputs the TR2 base signal “H” to the transistor TR2. As a result, the start switch SW1 is powered on to enable the start switch SW1, and the voltage supply to the stop switch SW2 is stopped to disable the stop switch SW2.

  In the next step S460, the CPU 11 determines whether or not the start switch SW1 has been operated based on the output of the comparison result information from the input voltage comparison circuit CC1. When the comparison result information from the input voltage comparison circuit CC1 corresponds to “H” (the operation signal output from the activation switch SW1 is “H”), the activation switch SW1 is regarded as not being operated, Control proceeds to step S480, which will be described later. On the other hand, when the comparison result information from the input voltage comparison circuit CC1 corresponds to “L” (the operation signal output from the start switch SW1 is “L”), it is considered that the start switch SW1 has been operated, Control proceeds to next step S470.

  In step S470, the CPU 11 turns on a flag indicating that the machine tool is in operation. Thereafter, the process proceeds to the next step S480.

  In step S480, the CPU 11 determines whether or not to end the process (for example, whether or not the power of the machine tool or the numerical control device 1B is turned off). When the process is finished, this flow is finished. On the other hand, if the process is not terminated, the process returns to the previous step S410 and the same procedure is repeated again.

  The flowchart is not intended to limit the present invention to the procedure shown in the flowchart, and the procedure may be added / deleted / changed without departing from the spirit and technical idea of the invention. Further, the flag in the above flow constitutes storage means for storing the operating state of the switch described in each claim.

  In the modified example described above, when the machine tool is in the activated state, the operation of the activation button is not necessary, and the stop button may be validated. Therefore, to the activation switch SW1 corresponding to the activation button. Is stopped and the start switch SW1 is invalidated. On the other hand, when the machine tool is in a stopped state, the operation of the stop button is not necessary, and the start button only needs to be enabled. Therefore, the voltage supply to the stop switch SW2 corresponding to the stop button is stopped. The stop switch SW2 is invalidated. In this way, according to the operation status (start / stop) of the machine tool, the power supply to the switch that does not need to operate substantially is substantially stopped, so that energy saving is achieved as in the above-described embodiment. And suppression of heat generation.

(3) When stopping the supply of voltage to unnecessary sensor switch circuits Depending on the operating conditions of the accessory devices provided in the machine tool, power supply can be saved by stopping the supply of voltage to sensor switches that do not need to be confirmed. You may make it show. Hereinafter, as an example of the accessory device, for example, when the supply of voltage to the switch corresponding to the clogging sensor (not shown) of the cooling water filter is stopped in accordance with the start / stop of the cooling water pump (not shown). I will explain to you.

  FIG. 11 is a block diagram illustrating a functional configuration of the numerical control device of the machine tool according to the present modification, and corresponds to FIG. 9 described above. Portions similar to those in FIG. 9 are denoted by the same reference numerals and description thereof is omitted.

  The numerical control apparatus 1C of this modification has a plurality of (three in this example) switch circuits corresponding to a plurality (three in this example) of switches SW1, SW2, and SW3. The switch SW1 is a cooling water pump start switch provided in the machine tool (hereinafter referred to as “pump start switch SW1”), and the switch SW2 is a cooling water pump stop switch (hereinafter referred to as “pump stop switch SW2”). The switch SW3 is a detection switch that outputs a detection signal of the clogging sensor of the cooling water filter (hereinafter referred to as “detection switch SW3”). The switch circuits corresponding to the pump start / stop switches SW1 and SW2 and the detection switch SW3 include a signal power supply 2 and load resistors provided in the circuits between the signal power supply 2 and the switches SW1, SW2 and SW3. R1, R2, and R3, and input voltage comparison circuits CC1, CC2, and CC3 that compare values of a plurality of operation signals output from the switches SW1, SW2, and SW3 and output corresponding comparison result information, respectively. Yes. The switch circuit corresponding to the detection switch SW3 is located in a circuit between the signal power supply 2 and the detection switch SW3, and the signal power supply 2 in accordance with a control signal (input signal) from the control circuit 10C described later. Has a transistor TR3 for switching the output voltage. Further, the numerical control device 1C performs control for stopping supply of voltage to the detection switch SW3 of the clogging sensor of the cooling water filter and the corresponding switch circuit in accordance with the operation state (start / stop) of the cooling water pump. A circuit 10C (control means) is included. Since the configuration of the control circuit 10C is the same as that of the control circuit 10B described above, description thereof is omitted.

  FIG. 12 is a flowchart showing the control contents executed by the CPU 11 of the control circuit 10C.

  First, in step S510, the CPU 11 determines whether or not a flag indicating that the cooling water pump is in operation is ON. If the flag is ON, the process proceeds to the next step S520.

  In step S520, the CPU 11 outputs the TR3 base signal “L” to the transistor TR3 via the input / output interface 14. As a result, the power is supplied to the detection switch SW3, and the clogging sensor of the cooling water filter is validated.

  In the next step S530, the CPU 11 determines whether or not the pump stop switch SW2 has been operated based on the output of the comparison result information from the input voltage comparison circuit CC2. When the comparison result information from the input voltage comparison circuit CC2 corresponds to “H” (the operation signal output from the pump stop switch SW2 is “H”), the pump stop switch SW2 is not operated. Therefore, the process proceeds to step S580 described later. On the other hand, when the comparison result information from the input voltage comparison circuit CC2 corresponds to “L” (the operation signal output from the pump stop switch SW2 is “L”), the pump stop switch SW2 is operated. Therefore, the process proceeds to the next step S540.

  In step S540, the CPU 11 turns off a flag indicating that the cooling water pump is in operation. Thereafter, the process proceeds to step S580 described later.

  On the other hand, if the flag indicating that the cooling water pump is in operation is OFF in the previous step S510, the CPU 11 proceeds to step S550.

  In step S550, the CPU 11 outputs the TR3 base signal “H” to the transistor TR3 via the input / output interface 14. Thereby, the voltage supply to the detection switch SW3 is stopped, and the clogging sensor of the cooling water filter is invalidated.

  In the next step S560, the CPU 11 determines whether or not the pump start switch SW1 has been operated based on the output of the comparison result information from the input voltage comparison circuit CC1. When the comparison result information from the input voltage comparison circuit CC1 corresponds to “H” (the operation signal output from the pump start switch SW1 is “H”), the pump start switch SW1 is not operated. Therefore, the process proceeds to step S580 described later. On the other hand, when the comparison result information from the input voltage comparison circuit CC1 corresponds to “L” (the operation signal output from the pump activation switch SW1 is “L”), the pump activation switch SW1 is operated. Therefore, the process proceeds to the next step S570.

  In step S570, the CPU 11 turns on a flag indicating that the cooling water pump is in operation. Thereafter, the process proceeds to the next step S580.

  In step S580, the CPU 11 determines whether or not to end the process (for example, whether or not the power of the machine tool or the numerical control device 1C is turned off). When the process is finished, this flow is finished. On the other hand, if the process is not terminated, the process returns to the previous step S510 and the same procedure is repeated again.

  The flowchart is not intended to limit the present invention to the procedure shown in the flowchart, and the procedure may be added / deleted / changed without departing from the spirit and technical idea of the invention. Further, the flag in the above flow constitutes storage means for storing the operating state of the switch described in each claim.

  In the modification described above, when the cooling water pump is in the activated state, the cooling water is discharged, so the clogging sensor that detects clogging of the cooling water filter is enabled and the cooling water pump stops. In the state, since the cooling water is not discharged, the supply of voltage to the detection switch SW3 corresponding to the clogging sensor of the cooling water filter is stopped, and the clogging sensor is invalidated. In this way, by stopping the voltage supply to the sensor that does not substantially require the effectiveness of the operation according to the operation state (start / stop) of the cooling water pump, the energy saving can be performed as in the above-described embodiment. And suppression of heat generation can be achieved.

  In the modification (3), transistors TR1 and TR2 may be provided in the switch circuits corresponding to the pump start / stop switches SW1 and SW2, and the same control as in the modification (2) may be performed. In the modification (3), the case where the clogging sensor of the cooling water filter is invalidated according to the start / stop of the cooling water pump has been described as an example. However, the modification (3) is applied to other accessory devices and sensors. May be.

(4) Others In the above, the transistor TR is provided in each switch circuit. However, the present invention is not limited to this, and one transistor TR may be shared by a plurality of switch circuits. FIG. 13 is a block diagram showing a functional configuration of the numerical control apparatus 1D in this case. FIG. 13 shows an example in which one transistor TR is shared by two switch circuits. The transistor TR1 is shared by switch circuits corresponding to the switches SW1 and SW2, and the transistor TR3 is a switch corresponding to the switches SW3 and SW4. Shared by circuit. In this case, the flip-flop circuits FF1 and FF2 and the flip-flop circuits FF3 and FF4 may be synchronized with the same FF clock signal. With such a configuration, the circuit configuration can be simplified.

  In the above description, the transistor TR is provided between the signal power source 2 and the switch SW. However, the present invention is not limited to this, and the transistor TR may be provided between the switch SW and the ground potential. In this case, the same effect as described above can be obtained.

  In addition to those already described above, the methods according to the above-described embodiments and modifications may be used in appropriate combination.

  In addition, although not illustrated one by one, the present invention is implemented with various modifications within a range not departing from the gist thereof.

It is a block diagram which shows the function structure of the numerical control apparatus of the machine tool of this embodiment. It is a flowchart showing the control content performed by CPU of a control circuit. It is a flowchart showing the detailed procedure of an input confirmation subroutine. It is a time chart showing the output state of TR base signal and FF clock signal from CPU. It is a block diagram which shows the function structure of the numerical control apparatus of a machine tool in the modification which shifts voltage switching timing. It is a flowchart showing the control content performed by CPU of a control circuit in the modification which shifts voltage switching timing. It is a flowchart showing the detailed procedure of the input confirmation subroutine in the modification which shifts a voltage switching timing. It is a time chart showing the output state of TR base signal and FF clock signal from CPU in the modification which shifts voltage switching timing. It is a block diagram which shows the function structure of the numerical control apparatus of a machine tool in the modification which stops the voltage supply to the unnecessary switch circuit according to the operation condition of a machine tool. It is a flowchart showing the control content performed by CPU of a control circuit in the modification which stops the voltage supply to the unnecessary switch circuit according to the operating condition of a machine tool. It is a block diagram which shows the function structure of the numerical control apparatus of a machine tool in the modification which stops the voltage supply to the unnecessary sensor switch circuit. It is a flowchart showing the control content performed by CPU of a control circuit in the modification which stops the voltage supply to the unnecessary sensor switch circuit. It is a block diagram which shows the function structure of the numerical control apparatus of a machine tool in the modification which shares one transistor TR with a some switch circuit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Numerical control apparatus 1A-D Numerical control apparatus 2 Signal power supply 10 Control circuit (control means)
10A to D Control circuit (control means)
FF flip-flop circuit (memory means)
FF1-4 flip-flop circuit (memory means)
R Load resistance (resistance)
R1-4 Load resistance (resistance)
SW switch SW1-4 switch TR transistor (switching means)
TR1-3 transistor (switching means)

Claims (6)

A switch, a signal power source that supplies power to the switch, and a resistor that is connected to the switch and restricts a current flowing through the switch, the signal power source is connected to one of the switches, and the other In a numerical control device having a switch circuit connected to the ground potential,
The switch circuit has switching means for switching whether to supply a voltage from the signal power source to the switch,
A numerical control device comprising storage means for storing an operating state of the switch when a voltage is supplied from the signal power source to the switch by the switching means. The numerical control device according to claim 1,
The switching means repeatedly supplies voltage from the signal power source to the switch for a predetermined time after supplying the voltage from the signal power source to the switch for a predetermined time. . The numerical control apparatus according to claim 2, wherein
A plurality of the switch circuits;
Numerical control comprising: control means for controlling each of the switching means so that time for supplying a voltage from the signal power supply to the switch does not overlap by the switching means of each switch circuit apparatus. The numerical control device according to claim 3,
The numerical controller according to claim 1, wherein the control unit controls the switching unit based on information stored in the storage unit. The numerical control apparatus according to claim 4, wherein
The switches of the plurality of switch circuits are configured by an automatic operation start switch for executing automatic operation of the machine tool and a stop switch for stopping the automatic operation,
If the control means stores in the storage means that the automatic operation start switch has been operated, the switching means of the switch circuit of the automatic operation start switch is switched from the signal power source to the automatic operation. If the control is performed so that no voltage is supplied to the start switch, and the storage means stores that the stop switch has been operated, the switching means of the switch circuit of the stop switch is switched from the signal power source. A numerical control device that controls so as not to supply a voltage to the stop switch. The numerical control apparatus according to any one of claims 1 to 5,
The switching means is
A numerical control device comprising a transistor for switching an output voltage in accordance with an input signal.

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