WO1987006727A1 - Signal input circuit - Google Patents
Signal input circuit Download PDFInfo
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- WO1987006727A1 WO1987006727A1 PCT/JP1987/000241 JP8700241W WO8706727A1 WO 1987006727 A1 WO1987006727 A1 WO 1987006727A1 JP 8700241 W JP8700241 W JP 8700241W WO 8706727 A1 WO8706727 A1 WO 8706727A1
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- WIPO (PCT)
- Prior art keywords
- signal
- input circuit
- generating means
- series
- circuit
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
- G05B19/05—Programmable logic controllers, e.g. simulating logic interconnections of signals according to ladder diagrams or function charts
- G05B19/054—Input/output
Definitions
- the invention relates to improvement of a signal input circuit.
- heat generated in the load resistance of a signal input circuit that uses the potential change or current change of a series circuit of a signal generating means such as a limit switch and a load resistance as a source information is used as source information.
- a signal generating means such as a limit switch and a load resistance as a source information
- FIGS. 1 and 2 show two examples of signal input circuits used in certain applications.
- reference numeral 2 denotes a load resistance
- reference numeral 3 denotes a signal generating means
- Numeral 4 is a signal voltage detecting means. * In the example, a comparator is used.
- Reference numeral 7 denotes a signal reading means, which reads the output signal of the signal voltage detecting means 4 at regular intervals. Arrows A and B indicate that A indicates an area outside the control box and B indicates an area inside the control box.
- Signal generation means 3 is not operating (open circuit) In this case, the power supply voltage is applied to the signal voltage detection means 4 as it is, but no voltage is applied to the signal voltage detection means 4 in the operation (closed) state. The voltage change is detected and the signal input is recognized. As described above, the signal reading means 7 reads the output signal of the signal voltage detecting means 4 at regular time intervals.
- 2 is a load resistance
- 3 is a signal generating means, and in the example, it is a limit switch.
- 5 is a signal current detecting means, which is a photo coupler in a typical example
- 6 is a level converter
- 8 is a signal reading means. Then, the output signal of the signal current detecting means 5 provided via the level converter 6 is read at a constant time interval.
- the signal generating means 3 is in a non-operating (open circuit) state
- the LED of the photocoupler 5 serving as the signal current detecting means does not emit light.
- the input signal is not applied, and a low-level signal is read by the signal reading means 8.
- the signal reading means 8 when the signal generating means 3 is in the operating (closed) state, the LED of the photocoupler 5 serving as the signal current detecting means emits light, and the signal reading means 8 is turned on. Is supplied with a high-level signal via a level converter 6, and the signal reading means 8 reads the high-level signal. In this way, the signal reading means 8 reads the output signal of the signal current detecting means 5 at regular time intervals.
- a load resistance is indispensable. Regardless of the operation, since the current flows continuously during the period in which the signal generating means 3 is closed, there is no power loss that cannot be ignored. It has a drawback that it occupies a considerable part of the total heat value of the whole, resulting in an increase in the amount of heat to be cooled for numerical control devices and the like.
- the signal generating means such as a limit switch is a contact type, a high voltage is applied to remove oxides and other insulators generated on the surface of the contact point.
- the voltage used for the signal input circuit having the above-mentioned configuration having a contact is generally about 24 V, which is a voltage normally used for a circuit including a semiconductor device.
- the disadvantages are particularly pronounced because they are much more expensive.
- the purpose of the invention is to provide a signal input circuit that uses a potential change or a current change of a series circuit of a signal generating means such as a limit switch and a load resistor as a source information as a primitive information. It is to provide an improvement that reduces the amount of heat generated during load resistance.
- a first signal input circuit relating to the invention comprises: a series circuit of signal generation means (3) and a resistor (2); and a signal generation means (3).
- the signal reading means is provided in a series circuit of the signal generating means (3) and the resistor (2). Synchronized to means (7) This is a signal input circuit to which a switching means (1) that operates by being added in series is added in series.
- a second signal input circuit includes a series circuit of a signal generating means (3) and a resistor (2), and a current flowing through the series circuit.
- the signal current detecting means (5) to be detected and the signal reading means (8) for intermittently reading the signal current detected by the signal current detecting means (5) are provided.
- a series circuit of the signal generating means (3) and the resistor (2) has a switch which operates in synchronization with the signal reading means (8). This is a signal input circuit to which the ring means (1) is added in series.
- FIG. 1 is a block diagram of a signal input circuit (voltage change detection method) according to the related art.
- FIG. 2 is a block diagram of a signal input circuit (current change detection method) according to the related art.
- FIG. 3 is a block diagram of a signal input circuit according to a first embodiment of the present invention (voltage change detection method).
- FIG. 4 is a block diagram of a signal input circuit according to a second embodiment of the present invention (voltage change detection method).
- FIG. 5 is a block diagram of a signal input circuit according to the third embodiment (current change detection method) of the * invention.
- FIG. 6 is a block diagram of a signal input circuit according to a fourth embodiment of the present invention (current change detection method). Detailed description of preferred embodiments 3 ⁇ 4
- reference numeral 1 denotes switching means, which opens and closes periodically in synchronization with the signal reading means 7.
- 2 is a load resistance
- 3 is a signal generating means, in this example, a limit switch
- 4 is a signal voltage detecting means. In the example, it is a comparator.
- Reference numeral 7 denotes a signal reading means, which reads the output signal of the signal voltage detecting means 4 at regular intervals. Arrows A and B indicate ', A indicates an area outside the control box, and B indicates an area inside the control box.
- the signal generating means 3 When the signal generating means 3 is in the non-operating (open) state, the voltage is still applied to the signal voltage detecting means, but it is in the operating (closed) state. Then, no voltage is applied to the signal voltage detecting means 4.
- the signal reading means 7 operates in synchronization with the operation of the switching means 1 and outputs the output signal of the signal voltage detecting means 4 for a certain period of time. Read each time
- the signal generating means 3 such as a limit switch operates in accordance with the operation of the numerically controlled machine tool or the like to which this signal input circuit is related, but this is read. Since the signal reading means 7 is effectively used only when the signal reading means 7 operates, the signal voltage is not used during the time when the signal reading means 7 is inactive. Detection Step 4 does not need to work *
- the switching means 1 operates in synchronization with the signal reading means 7 by utilizing this principle.
- the input signal can be normally backed up without any inconvenience, but the switching means is not used during the period when the signal reading means 7 is inactive. Since 1 is inactive, no heat is generated in the load resistance 2 except during the period in which the input signal is up. As a result, the amount of heat in the entire control device is greatly reduced.
- Second embodiment Second embodiment
- 1 and la are switching means that operate in synchronization with the signal reading means 7 and 7a, and each is closed at a separate time.
- Reference numerals 21 to 23 and 21a to 23a denote load resistors, which are connected to the switching means 1 or the switching means 1a, respectively.
- 31 to 33 and 31a to 33a are signal generating means such as limit switches, which are connected in series between the load resistances 21 to 23 and 21a to 23a and the ground, respectively.
- 41 to 43 and 41a to 43a are signal voltage detecting means for detecting voltage signals corresponding to the open / closed states of the signal generating means 31 to 33 and 31a to 33a, respectively.
- a group of signals that are up-taken at the same time for example, a set of signals detected by the voltage detection means 41 to 43 is used for the same function as a set.
- the output signal of comparator 41 and the output of 41a The output signal of the comparator 42 and the output signal of the comparator 42a form a set, and the output signal of the comparator 43 and the output signal of the comparator 43a form a set.
- the output signals of the above may be used as a set, and A may be used as wiring, and A may be wiring outside the numerical control device, for example, wiring to be attached to a machine tool.
- B indicates the g-line in the numerical control device.
- the switching means 1 and la are supposed to operate in synchronization with the signal reading means 7 and 7a, and the signal reading means 1 and la are operated in synchronization with the signal reading means 7 and 7a. Since the switching means 1 and la are inactive during the period when the input means 7 and 7a are inactive, the switching means 1 and la are inactive during the period other than the period during which the input signal is turned on. Does not generate heat in the load resistors 2, 21, 22, 23, 21a, 22a, and 23a. Therefore, the heat value of the entire control device is greatly reduced.
- reference numeral 1 denotes switching means, which opens and closes periodically in synchronization with the signal reading means 8.
- 2 is a load resistance
- 3 is a signal generation means, and in the last example, it is a limit switch.
- 5 is a signal current detecting means, which is a photocoupler in this example
- 6 is a level converter
- 8 is a signal reading means.
- Signal generation means 3 does not operate (open In this state, the LED of the photocoupler 5 serving as the signal current detecting means does not emit light, so that no input signal is applied to the level converter 6, A low level signal is read by the signal reading means 8.
- the signal generating means 3 when the signal generating means 3 is in the operating (closed) state, the LED of the photocoupler 5 serving as signal current detecting means emits light, and the signal reading means 8 is turned on. A high level signal is given to the signal via the level converter 6, and the signal reading means 8 reads a high level signal.
- the switching means 1 since the switching means 1 is supposed to operate in synchronization with the signal reading means 8, the input signal is up-converted. Is normally performed without any inconvenience, but on the other hand, during the period when the signal reading means 8 is inactive, the switching signal 1 is inoperable, so that the input signal is not operated. No heat is generated in the load resistance 2 except during the period during which the voltage is up. Therefore, the amount of heat generated by the control device as a whole is greatly reduced.
- 1 and la are switching means operating in synchronism with the signal reading means 8 and 8a, and are closed at the time of each other.
- 21 to 23, and 21a to 23a are load resistances, which are connected to the switching means 1 or the switching means 1a, respectively.
- 31-33, 31a-33a are the limits
- a signal generating means such as a tos switch, etc., each of which is kneaded in series between the load resistances 21 to 23, 21a to 23a and the ground
- 51, 52, 53, 51a, 52a, and 53a are signal current detection means, and are photocouplers in the example.
- 82, 83, 61a, 81b, and 81c are level converters, and 8a and 8b are signal reading means.
- the output signals of the signal current detecting means 51, 52, 53, 51a, 52a, 53a provided via 83, 81a, 81b, 81c are read at regular intervals. Yes.
- the signal generating means 31 to 33, 31a to 33a are in a non-operating (open circuit) state, the photo couplers 51, 52, 53, 51a and 51a serving as signal current detecting means are provided. Since the 52a and 53a LEDs do not emit light, the input signal is not applied to the level converters 82, 83, 81a, 81b, and 81c, and the signal is read.
- the low level signal is read by the first and second means 8 and 8a.
- the signal generating means 31 to 33 and 31a to 33a When the signal generating means 31 to 33 and 31a to 33a are in the operation (closed) state, the signal is low.
- a high-level signal is obtained via the converters 62, 83, 81a, 81b, and 81c, and the signal reading means 8, 8a reads the high-level signal.
- the switching means 1 and la are supposed to operate in synchronization with the signal reading means 8 and 8a, the signal reading means 8 and 8a Since switching means 1 and la are inactive during the period during which the input signal is inactive, the load resistance 2 must be used during periods other than the period during which the input signal is There is no fever in it. Therefore, the amount of heat generated by the control device as a whole is significantly reduced. It clearly shows that the improvement has been completed to reduce the amount of heat generated in the load resistor in the signal input circuit that uses the potential change or current change of the series circuit as the primitive information. .
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Abstract
In a signal input circuit in which the potential change or the current change of a series circuit consisting of a signal generating means, such as a limit switch and a load resistance, serves as an original data, an improvement is made for reduction in an amount of heat generated in the load resistance. In a signal input circuit having signal read means (7 or 8) which intermittently reads the potential change or the current change of a series circuit consisting of a signal generating means (3), such as a limit switch, and a load resistance (2), a switching means (1) which operates in synchronism with the signal read means (7 or 8) is added in series with the series circuit which consists of the signal generating means (3) and the resistance (2).
Description
明 細 書 Specification
発明 の名称 Title of invention
信号入力 回路 Signal input circuit
発明 の技衛分野 Technical field of invention
术発明 は信号入力 回路 の 改良 に 関 す る 。 特 に 、 リ ミ ツ ト ス ィ ツ チ等 の信号発生手段 と 負荷抵抗 と の直列 回路 の 電位変化 ま た は電流変化 を 原始情報 と す る 信号入力 回路 の 負荷抵抗 中 に お け る 発熱 を 防止 す る 改 良 に 関 す る 。 技術 の背景 术 The invention relates to improvement of a signal input circuit. In particular, heat generated in the load resistance of a signal input circuit that uses the potential change or current change of a series circuit of a signal generating means such as a limit switch and a load resistance as a source information is used as source information. Regarding improvements to prevent. Technology background
数値制御装置等 に は 多数 の リ ミ ッ ト ス ィ ツ チ等 の信号 発生手段が使用 され て お り 、 こ の信号発生手段の癸す る 信号 は数値制御装置等 に よ リ 逐次受信 さ れ プ ロ グ ラ ム の 進行指令 と され る 。 た 、 こ の 入力信号 の受信 は 、 数値 制御装置等 の 常 と し て 、 常時 な さ れ る の では な く 、 一定 時間毎 に ペ リ オデ イ カ ル に な さ れ る こ と が一般 で あ る ， か ゝ る 用 途 に使用 さ れ る 信号入力 回路 の 2 例 を 、 第 1 図 と 第 2 図 と に示す， A number of limit switches or other signal generating means are used in a numerical control device or the like, and the signals generated by the signal generating means are sequentially received by the numerical control device or the like. This is used as a program progress command. In addition, the reception of this input signal is not always performed as always in a numerical control device or the like, but is performed periodically and periodically. FIGS. 1 and 2 show two examples of signal input circuits used in certain applications.
第 1 図 に お い て は 、 2 は 負 荷抵抗 で あ り 、 3 は 信 号 発生手段 で ぁ リ 、 末例 に お い て は リ ミ ツ ト ス イ ッ チ で あ る 。 4 は 信 号電 圧検 出 手 段 で ぁ リ 、 *例 に お い て は 、 比較器 で あ る 。 7 は信号読 み込 み手段 で あ り 、 信号電圧 検 出 手段 4 の 出 力信号 を 一定時間毎 に 読 み込 む 。 な お 、 矢印 A 、 B は 、 A が制御箱外 の 領域 を 、 B が制铟箱内 の 領域 を 示す。 信号発生手段 3 が不動作 （開路） 状態 に あ
る と き は 信 号電 圧検 出 手 段 4 に は電源 電圧 が そ の ま 印加 され て い る が、 動作 （閉路） 状態 に な る と 信号電圧 検 出 手段 4 に は 無 電圧 が 印 加 さ れ る こ と に な リ 、 こ の 電圧変化 を検 出 し て信号入 力 を 認識す る 。 信号読み込み 手段 7 は 、 上記せ る と お り 、 信号電圧検 出手段 4 の 出力 信号 を一定時間毎 に 読 み込 む 。 In FIG. 1, reference numeral 2 denotes a load resistance, reference numeral 3 denotes a signal generating means, and in a rare case, a limit switch. Numeral 4 is a signal voltage detecting means. * In the example, a comparator is used. Reference numeral 7 denotes a signal reading means, which reads the output signal of the signal voltage detecting means 4 at regular intervals. Arrows A and B indicate that A indicates an area outside the control box and B indicates an area inside the control box. Signal generation means 3 is not operating (open circuit) In this case, the power supply voltage is applied to the signal voltage detection means 4 as it is, but no voltage is applied to the signal voltage detection means 4 in the operation (closed) state. The voltage change is detected and the signal input is recognized. As described above, the signal reading means 7 reads the output signal of the signal voltage detecting means 4 at regular time intervals.
第 2 図 に お い て は 、 2 は 負 荷 抵抗 で あ り 、 3 は 信号. 発生手段 で あ り 、 *例 に お い て は リ ミ ツ ト ス イ ッ チ で あ る 。 5 は信号電流検 出手段 で あ り 、 太例 に お い て は フ ォ ト カ プ ラ ー で あ り 、 6 は レ ベ ル変換器 で ぁ リ 、 8 ほ信号 読 み込み手段 で あ ϋ 、 レ ベ ル変換器 6 を 介 し て与 え られ る 信号電流検出手段 5 の 出 力信号 を一定時間每 に 読 み込 む 。 信号発生手段 3 が 不動作 （開路） 状態 に あ る と き は 、 信号電流検 出手段 を な す フ ォ ト カ プ ラ ー 5 の L E D は発光 し な いた め 、 レ ベ ル変換器 6 に は入力信号 は印加 さ れず、 信号読み込 み手段 8 に よ っ て は低 レ ベル信号が 読 み込 まれ る 。 一方 、 信号発生手段 3 が動作 （閉路） 状 態 に な る と 、 信号電流検 出手段 を な す フ ォ ト カ プ ラ ー 5 の L E D は 発光 し て 、 信 号読 み 込 み 手 段 8 に は レ ベ ル 変換器 6 を 介 し て高 レ ベ ル信号が与 え ら れ、 信号読み込 み手段 8 は高 レ ベル信号 を 読 み込 む 。 こ の よ う に し て 、 信号読み込み手段 8 は 、 信号電流検 出手段 5 の 出 力信号 を 一定時間毎 に読 み込 む 。 In FIG. 2, 2 is a load resistance, 3 is a signal generating means, and in the example, it is a limit switch. 5 is a signal current detecting means, which is a photo coupler in a typical example, 6 is a level converter, and 8 is a signal reading means. Then, the output signal of the signal current detecting means 5 provided via the level converter 6 is read at a constant time interval. When the signal generating means 3 is in a non-operating (open circuit) state, the LED of the photocoupler 5 serving as the signal current detecting means does not emit light. The input signal is not applied, and a low-level signal is read by the signal reading means 8. On the other hand, when the signal generating means 3 is in the operating (closed) state, the LED of the photocoupler 5 serving as the signal current detecting means emits light, and the signal reading means 8 is turned on. Is supplied with a high-level signal via a level converter 6, and the signal reading means 8 reads the high-level signal. In this way, the signal reading means 8 reads the output signal of the signal current detecting means 5 at regular time intervals.
上記 の信号入力 回路 に お い て は 、 負荷抵抗が必須 で あ り 、 こ の 負荷抵抗 に は 、 信号読 み込 み手段 の動作 ， 不動
作 に か わ り な く 、 信号発生手段 3 が閉路 し て い る 期間 齄統 し て電流が流れ る た め 、 無視 し え な い 大 き さ の電力 損失 を と も な い 、 数値制御装置等全体 の発熱量 の か な り な部分 を 占 め て お り 、 数値制御装置等 の冷却 すべ き 熱量 を 増加す る 結果 に な る と い う 欠点が あ る 。 特 に 、 リ ミ ツ ト ス イ ッ チ等 の信号発生手段が接触型 で あ る 場合 は 、 接 点 の 表面 に 生成 さ れ る 酸化物等 の絶縁物 を 除去す る た め に 高電圧 を 印 加す る 必要が あ る か ら 、 接点 を 有す る 上記 の構成 の信号入力 回路 に使用 され る 電圧 は一般 に 24 V 程 度で あ り 半導体装置 を 合 む 回路 に 通常使用 され る 電圧 よ リ 遙か に高 い の で 、 上記 の 欠点 は特 に 顕著 で あ る 。 In the above-described signal input circuit, a load resistance is indispensable. Regardless of the operation, since the current flows continuously during the period in which the signal generating means 3 is closed, there is no power loss that cannot be ignored. It has a drawback that it occupies a considerable part of the total heat value of the whole, resulting in an increase in the amount of heat to be cooled for numerical control devices and the like. In particular, when the signal generating means such as a limit switch is a contact type, a high voltage is applied to remove oxides and other insulators generated on the surface of the contact point. Since it is necessary to apply a voltage, the voltage used for the signal input circuit having the above-mentioned configuration having a contact is generally about 24 V, which is a voltage normally used for a circuit including a semiconductor device. The disadvantages are particularly pronounced because they are much more expensive.
発明 の 目 的 と 発明 の 開示 Purpose of the Invention and Disclosure of the Invention
*発明 の 目 的 は 、 リ ミ ッ ト ス ィ ッ チ等 の信号発生手段 と 負荷抵抗 と の直列 回路 の電位変化 ま た は電流変化 を 原 始情報 と す る 信号入力 回路 に お い て 、 負荷抵抗 中 に発生 す る 発熱量 を 減少す る 改良 を 提供す る こ と に あ る 。 * The purpose of the invention is to provide a signal input circuit that uses a potential change or a current change of a series circuit of a signal generating means such as a limit switch and a load resistor as a source information as a primitive information. It is to provide an improvement that reduces the amount of heat generated during load resistance.
末 発 明 の 目 的 を 達成 す る 、 * 発 明 に 係 る 第 1 の 信号 入力 回路は 、 信号発生手段 （ 3 ) と 抵抗 （ 2 ) と の直列 回路 と 、 前記信号発生手段 （ 3 ) と 前記抵抗 （ 2 ) と の 接練点 の電位 を 検 出 す る 信号電圧検 出手段 （ 4 ) と 、 該 信号電圧検 出 手段 （ 4 ) の検 出 す る 信号電位 を 間欠的 に 読 み込 む信号読 み込み手段 （ 7 ) と を 有す る 信号入 力 回 路 に お い て 、 前記信号発生手段 （ 3 ) と 前記抵抗 （ 2 ) と の直列 回路 に は 、 前記信号読 み込 み手段 （ 7 ) に 同期
し て動作す る ス イ ッ チ ン グ手段 （ 1 ) が直列 に 付加 され て な る 信号入力回路 で あ る 。 To achieve the purpose of the last invention, * a first signal input circuit relating to the invention comprises: a series circuit of signal generation means (3) and a resistor (2); and a signal generation means (3). A signal voltage detecting means (4) for detecting a potential at a kneading point with the resistor (2); and a signal potential detected intermittently by the signal voltage detecting means (4). In a signal input circuit having signal reading means (7), the signal reading means is provided in a series circuit of the signal generating means (3) and the resistor (2). Synchronized to means (7) This is a signal input circuit to which a switching means (1) that operates by being added in series is added in series.
术発明 の 目 的 を 達成す る 、 术発明 に係 る 第 2 の信号入 力 回路は 、 信号発生手段 （ 3 ) と 抵抗 （ 2 ) と の直列 回 路 と 、 該直列 回路 に 流れ る 電流 を 検 出 す る 信号電流検 出 手段 （ 5 ) と 、 該信号電流検 出手段 （ 5 ) の検 出 す る 信 号電流 を 間欠的 に 読 み込 む信号読 み込 み手段 （ 8 ) と を 有す る 信号入力回路 に お い て 、 前記信号発生手段 （ 3 ) と 前記抵抗 （ 2 ) と の直列 回路 に は 、 前記信号読 み込み 手段 （ 8 ) に 同期 し て動作す る ス イ ッ チ ン グ手段 （ 1 ) が直列 に付加 され て な る 信号入力 回路 で あ る 。 図面 の簡単 な説明 (2) To achieve the object of the invention, (2) A second signal input circuit according to the invention includes a series circuit of a signal generating means (3) and a resistor (2), and a current flowing through the series circuit. The signal current detecting means (5) to be detected and the signal reading means (8) for intermittently reading the signal current detected by the signal current detecting means (5) are provided. In a signal input circuit having the same, a series circuit of the signal generating means (3) and the resistor (2) has a switch which operates in synchronization with the signal reading means (8). This is a signal input circuit to which the ring means (1) is added in series. Brief description of the drawings
以下 に特定す る 図面 を 参照 し っ 、 本発明 の実施倒 に 係 る 信号入力回路 に つ い て さ ら に詳 し く 説明 す る 。 With reference to the drawings specified below, a signal input circuit according to an embodiment of the present invention will be described in more detail.
第 1 図 は 、 従来技術 に 係 る 信 号入 力 回路 （電圧変化 検 出方式） の ブ ロ ッ ク 図 で あ る 。 FIG. 1 is a block diagram of a signal input circuit (voltage change detection method) according to the related art.
第 2 図 は 、 従来技術 に 係 る 信 号入 力 回路 （ 電流 変化 検出方式） の ブ ロ ッ ク 図 で あ る 。 FIG. 2 is a block diagram of a signal input circuit (current change detection method) according to the related art.
第 3 図 は 、 末 発 明 の 第 1 の 実 施例 （電圧 変化検 出 方 式） に 係 る 信号入力 回路 の ブ ロ ッ ク 図 で あ る 。 FIG. 3 is a block diagram of a signal input circuit according to a first embodiment of the present invention (voltage change detection method).
第 4 図 は 、 术発 明 の 第 2 の 実施例 （ 電圧 変化検 出 方 式） に 係 る 信号入力 回路 の ブ ロ ッ ク 図 で あ る 。 FIG. 4 is a block diagram of a signal input circuit according to a second embodiment of the present invention (voltage change detection method).
第 5 図 は 、 * 発 明 の 第 3 の 実施例 （ 電流 変 化検 出 方 式） に係 る 信号入力 回路 の ブ ロ ッ ク 図 で あ る 。
第 6 図 は 、 *発 明 の 第 4 の 実 施例 （電流 変 化検 出 方 式 ) に 係 る 信号入力回路の ブ ロ ッ ク 図 で あ る 。 好 ま し い実施例 の詳細 な説 ¾ FIG. 5 is a block diagram of a signal input circuit according to the third embodiment (current change detection method) of the * invention. FIG. 6 is a block diagram of a signal input circuit according to a fourth embodiment of the present invention (current change detection method). Detailed description of preferred embodiments ¾
I の実施例 Example of I
第 3 図参照 See Fig. 3
図 に お い て 、 1 は ス ィ ツ チ ン グ 手段 で あ り 、 信号読 み 込 み手段 7 と 同期 し て周期的 に 開 閉す る 。 2 は 負荷抵抗 で あ り 、 3 は信 号 発生手 段 で あ り 、 术 例 に お い て は リ ミ ッ ト ス ィ ッ チ で あ る ， 4 は信号電圧検 出手段 で ぁ リ 、 本例 に おい て は 、 比較器 で あ る 。 7 は信号読 み込 み手段 で あ り 、 信号電圧検 出 手段 4 の 出 力信号 を一定時間毎 に 読 み込 む 。 な お、 矢印 A 、 B は'、 A が制铒箱外 の領域 を B が制御 箱 内 の 領域 を 示 す 。 信 号 発 生 手段 3 が不 動 作 (開路） 状態 に あ る と き は信号電圧検 出 手段 に は電漯 電圧が そ の ま 印加 さ れ て い る が 、 動作 （閉路） 状態 に な る と 信号電圧検出手段 4 に は無電圧が印 加 さ れ る こ と に な る 。 信 号読 み 込 み 手 段 7 は 、 上 記 せ る と お り 、 ス ィ ツ チ ン グ手段 1 の動作 と 同期 し て動作 し 、 信号電圧検 出 手段 4 の 出 力信号 を 一定晦間毎 に 読み込 む In the figure, reference numeral 1 denotes switching means, which opens and closes periodically in synchronization with the signal reading means 7. 2 is a load resistance, 3 is a signal generating means, in this example, a limit switch, and 4 is a signal voltage detecting means. In the example, it is a comparator. Reference numeral 7 denotes a signal reading means, which reads the output signal of the signal voltage detecting means 4 at regular intervals. Arrows A and B indicate ', A indicates an area outside the control box, and B indicates an area inside the control box. When the signal generating means 3 is in the non-operating (open) state, the voltage is still applied to the signal voltage detecting means, but it is in the operating (closed) state. Then, no voltage is applied to the signal voltage detecting means 4. As described above, the signal reading means 7 operates in synchronization with the operation of the switching means 1 and outputs the output signal of the signal voltage detecting means 4 for a certain period of time. Read each time
リ ミ ッ ト ス ィ ツ チ等 の信号発生手段 3 は こ の信号入力 回路が関建す る 数値制御工作機械等 の動作 に し た が っ て 動作す る が 、 こ れが読 み込 ま れ て有効 に 利用 さ れ る の は 信 号 読 み 込 み手 段 7 の 動 作 す る と き の み で あ る か ら 、 信号読 み込 み手段 7 が不動作 の 時間帯 に 信号電圧検 出 手
段 4 が動作す る 必要 は な い * The signal generating means 3 such as a limit switch operates in accordance with the operation of the numerically controlled machine tool or the like to which this signal input circuit is related, but this is read. Since the signal reading means 7 is effectively used only when the signal reading means 7 operates, the signal voltage is not used during the time when the signal reading means 7 is inactive. Detection Step 4 does not need to work *
本実施例 に あ っ て は 、 こ の原理 を 活用 し て 、 ス ィ ッ チ ン グ手段 1 が、 信号読 み込 み手段 7 に 同期 し て動作す る こ と と さ れて い る の で、 入力信号 の ビ ッ ク ア ッ プ は全 く 不都合 な く 正常 に な さ れ る が、 し か し一方 、 信号読み込 み手段 7 が不動作 の期 間 は ス ィ ツ チ ン グ手段 1 は不動作 で あ る か ら 、 入力信号が ビ ッ ク ア ッ プ さ れ る 期間以外 に は 、 負荷抵抗 2 中 に は 発熱 ほ 存在 し な い 。 そ の た め 、 制御装置全体 と し て の癸熱量は大幅 に 減少す る 。 第 2 の実施例 In the present embodiment, the switching means 1 operates in synchronization with the signal reading means 7 by utilizing this principle. In this case, the input signal can be normally backed up without any inconvenience, but the switching means is not used during the period when the signal reading means 7 is inactive. Since 1 is inactive, no heat is generated in the load resistance 2 except during the period in which the input signal is up. As a result, the amount of heat in the entire control device is greatly reduced. Second embodiment
第 4 図参照 See Fig. 4
図 に おい て 、 1 、 l a は信号読み込 み手段 7 、 7 a に 同期 し て動作す る ス イ ッ チ ン グ手段 で あ り 、 各 々 、 別個 の 時点 に 閉路 され る 。 21〜 23、 21 a 〜 23 a は 負荷抵抗で ぁ リ 、 そ れ ぞれ 、 ス イ ッ チ ン グ手段 1 ま た は ス ィ ッ チ ン グ手段 1 a に接統 さ れ る 。 31〜 33、 31 a 〜 33 a が リ ミ ツ ト ス イ ッ チ等の信号発生手段 で あ り 、 それぞれ 、 負荷抵 抗 21〜 23、 21 a 〜 23 a と 接地 と の 間 に 直列 に 接統 さ れ る 。 41〜 43、 41 a 〜 43 a は信号電圧検 出手段 で あ り 、 そ れ ぞ れ信 号 発生手段 31〜 33、 31 a 〜 33 a の 開 閉妆 態 に 対応す る 電圧信号 を 検 出 す る 。 な お、 同 時 に ビ ッ ク ア ツ プ さ れ る 信号群例 え ば電圧検 出手段 41〜 43に よ つ て検 出 さ れ る 信号の組が 、 組 と し て 同一の機能 に 使用 さ れ る と は 限 ら な い 。 例 え ば 、 比較器 41の 出 力信号 と 41 a の 出力
信 号 と が組 と し て 、 ま た 、 比 較 器 42の 出 力 信 号 と 比 較 器 42 a の 出 力信号 と が組 と し て 、 比較器 43の 出 力信号 と 比較器 43 a の 出 力信号 と が組 と し て 、 そ れぞれ使用 さ れ て も よ い ， ま た 、 A は数値制御装置外 の配線 ^ え ば工作 機械 に取 り 付 け ら れ る 配線 を 、 ま た 、 B は数値制铒装置 内 の g線 を 示す。 In the figure, 1 and la are switching means that operate in synchronization with the signal reading means 7 and 7a, and each is closed at a separate time. Reference numerals 21 to 23 and 21a to 23a denote load resistors, which are connected to the switching means 1 or the switching means 1a, respectively. 31 to 33 and 31a to 33a are signal generating means such as limit switches, which are connected in series between the load resistances 21 to 23 and 21a to 23a and the ground, respectively. Be governed. 41 to 43 and 41a to 43a are signal voltage detecting means for detecting voltage signals corresponding to the open / closed states of the signal generating means 31 to 33 and 31a to 33a, respectively. You At the same time, a group of signals that are up-taken at the same time, for example, a set of signals detected by the voltage detection means 41 to 43 is used for the same function as a set. This is not necessarily the case. For example, the output signal of comparator 41 and the output of 41a The output signal of the comparator 42 and the output signal of the comparator 42a form a set, and the output signal of the comparator 43 and the output signal of the comparator 43a form a set. The output signals of the above may be used as a set, and A may be used as wiring, and A may be wiring outside the numerical control device, for example, wiring to be attached to a machine tool. B indicates the g-line in the numerical control device.
本実施例 に あ っ て も 、 ス イ ッ チ ン グ手段 1 、 l a が 、 信号読み込 み手段 7 、 7 a に 同期 し て動作す る こ と と さ れ て お り 、 信号読 み込 み手段 7 、 7 a が不動作 の期間 は ス イ ッ チ ン グ手 段 1 、 l a は 不 動 作 で あ る か ら 、 入 力 信号が ビ ッ ク ア ッ プ さ れ る 期 間以外 に は 、 負荷抵抗 2 、 21、 22、 23、 21 a 、 22 a 、 23 a 中 に は 発熱 は 存在 し な い 。 そ の た め 、 制 御装 置 全体 と し て の 発熱 量'は大 幅 に 減少す る ， 第 3 の実施例 Also in the present embodiment, the switching means 1 and la are supposed to operate in synchronization with the signal reading means 7 and 7a, and the signal reading means 1 and la are operated in synchronization with the signal reading means 7 and 7a. Since the switching means 1 and la are inactive during the period when the input means 7 and 7a are inactive, the switching means 1 and la are inactive during the period other than the period during which the input signal is turned on. Does not generate heat in the load resistors 2, 21, 22, 23, 21a, 22a, and 23a. Therefore, the heat value of the entire control device is greatly reduced. The third embodiment
第 5 図参照 See Fig. 5
図 に お い て 1 は ス イ ッ チ ン グ手段 で あ り 、 信号読み 込 み手段 8 と 同期 し て 周期的 に 開閉す る 。 2 は 負荷抵抗 で あ り 、 3 は信 号 発生 手 段 で ぁ リ 、 末 例 に お い て は リ ミ ッ ト ス ィ ッ チ で あ る 。 5 は信号電流検 出手段 で あ り 、 本例 に お い て は フ ォ ト カ プ ラ ー で あ り 、 6 は レ ベ ル変換 器 で あ り 、 8 は 信 号 読 み 込 み 手 段 で あ り 、 レ ベ ル 変換 器 6 を 介 し て与 え ら れ る 信号電流検 出手段 5 の 出 力信号 を 一定時間毎 に読 み込 む 。 信号発生手段 3 が不動作 （開
路） 状態 に あ る と き は 、 信号電流検出手段 を な す フ ォ ト カ プ ラ ー 5 の L E D は発光 し な い た め 、 レ ベ ル変換器 6 に は入力信号 は印加 さ れず 、 信号読 み込み手段 8 に よ つ て は 低 レ ベ ル信号 が読 み 込 ま れ る 。 一 方 、 信 号発生 手 段 3 が動作 （閉路） 状態 に な る と 、 信号電流検 出手段 を な す フ ォ ト カ プ ラ ー 5 の L E D は発光 し て 、 信号読 み込 み手段 8 に は レ.ペル変換器 6 を 介 し て高 レ ペル信号が与 え ら れ 、 信 号読 み 込 み手段 8 ほ 高 レ ベ ル信 号 を 読 み込 む 。 In the figure, reference numeral 1 denotes switching means, which opens and closes periodically in synchronization with the signal reading means 8. 2 is a load resistance, 3 is a signal generation means, and in the last example, it is a limit switch. 5 is a signal current detecting means, which is a photocoupler in this example, 6 is a level converter, and 8 is a signal reading means. Thus, the output signal of the signal current detecting means 5 provided via the level converter 6 is read at regular intervals. Signal generation means 3 does not operate (open In this state, the LED of the photocoupler 5 serving as the signal current detecting means does not emit light, so that no input signal is applied to the level converter 6, A low level signal is read by the signal reading means 8. On the other hand, when the signal generating means 3 is in the operating (closed) state, the LED of the photocoupler 5 serving as signal current detecting means emits light, and the signal reading means 8 is turned on. A high level signal is given to the signal via the level converter 6, and the signal reading means 8 reads a high level signal.
* 実 施 例 に あ っ て も 、 ス イ ッ チ ン グ 手段 1 が 、 信号 読み込み手段 8 に 同期 し て動作す る こ と と されて い る の で 、 入力信号の ビ ッ ク ア ッ プ は全 く 不都合 な く 正常 に な さ れ る が、 し か し一方、 信号読 み込み手段 8 が不動作の 期間 は ス イ ッ チ ン グ手段 1 は不動作で ある か ら 、 入力信 号が ビ ッ ク ア ッ プ さ れ る 期間以外 に ほ 、 負荷抵抗 2 中 に は発熱 は存在 し な い 。 そ の た め 、 制御装置全体 と し て の 癸熱量 は大幅 に減少す る 第 4 の実施例 * Even in the embodiment, since the switching means 1 is supposed to operate in synchronization with the signal reading means 8, the input signal is up-converted. Is normally performed without any inconvenience, but on the other hand, during the period when the signal reading means 8 is inactive, the switching signal 1 is inoperable, so that the input signal is not operated. No heat is generated in the load resistance 2 except during the period during which the voltage is up. Therefore, the amount of heat generated by the control device as a whole is greatly reduced.
第 6 図参照 See Fig. 6
図 に お い て 、 1 、 l a は信号読 み込 み手段 8 、 8 a に 同期 し て動作す る ス イ ッ チ ン グ手段 で ぁ リ 、 各 々 、 別倔 の 時点 に 閉路 さ れ る ， 21〜 23、 21 a 〜 23 a は 負荷抵抗で あ り 、 それぞれ 、 ス イ ッ チ ン グ手段 1 ま た は ス ィ ッ チ ン グ手段 1 a に接続 さ れ る 。 31〜 33、 31 a 〜 33 a が リ ミ ツ
ト ス イ ッ チ 等 の 信 号発生 手段 で あ り 、 そ れ ぞ れ 、 負 荷 抵抗 21〜 23、 21 a 〜 23 a と 接地 と の 間 に 直列 に接練 さ れ る ， 51、 52、 53、 51 a 、 52 a 、 53 a は 信号 電 流検 出 手 段 で あ り 、 *例 に お い て は フ ォ ト カ プ ラ ー で あ り 、 61、In the figure, 1 and la are switching means operating in synchronism with the signal reading means 8 and 8a, and are closed at the time of each other. , 21 to 23, and 21a to 23a are load resistances, which are connected to the switching means 1 or the switching means 1a, respectively. 31-33, 31a-33a are the limits A signal generating means such as a tos switch, etc., each of which is kneaded in series between the load resistances 21 to 23, 21a to 23a and the ground, 51, 52, 53, 51a, 52a, and 53a are signal current detection means, and are photocouplers in the example.
82、 83、 61 a , 81 b 、 81 c は レ ベ ル変換器 で ぁ リ 、 8 a 8 b は信号読み込 み手段 で あ り 、 レ ベ ル変換器 81、 82、82, 83, 61a, 81b, and 81c are level converters, and 8a and 8b are signal reading means.
83、 81 a 、 81 b 、 81 c を 介 し て 与 え ら れ る 信号電流検 出 手段 51、 52、 53、 51 a 、 52 a , 53 a の 出 力信号 を 一定 時 間毎 に 読 み込 む。 信号発生手段 31〜 33、 31 a 〜 33 a が不 動作 （開路） 状態 に あ る と き は 、 信号電流検 出 手段 を な す フ ォ ト カ プ ラ ー 51、 52、 53、 51 a 、 52 a 、 53 a の L E D は発光 し な い た め 、 レ ペル変換器 8し 82、 83、 81 a 、 81 b 、 81 c に は 入力 信 号 は 印 加 さ れ ず 、 信 号 読 み 込 み 手段 8 、 8 a に よ っ て は低 レ ベル信号が読 み込 ま れ る ， —方 、 信号発生手段 31〜 33、 31 a 〜 33 a が動作 （閉路） 状態 に な る と 、 信号電流検 出 手段 を なす フ ォ ト カ プ ラ ー 51、 52、 53、 51 a 、 52 a 、 53 a の L E D は発光 し て 、 信 号読 み込 み手段 8 、 8 a に は レ ベ ル変換器 6し 62、 83、 81 a 、 81 b 、 81 c を 介 し て 高 レ ベ ル信号が年え ら れ 、 信 号読 み込 み手段 8 、 8 a は高 レ ベ ル信号 を 読 み込 む * 太実施例 に あ っ て も 、 ス イ ッ チ ン グ手段 1 、 l a が 、 信号読み込 み手段 8 、 8 a に 同期 し て動作す る こ と と さ れ い る の で 、 信号読 み込 み手段 8 、 8 a が不動作の 期 間 は ス イ ッ チ ン グ手段 1 、 l a は不動作 で あ る か ら 、 入 力信号が ビ ッ ク ア ッ プ さ れ る 期間以外 に は 、 負荷抵抗 2
中 に は発熱 は存在 し な い 。 そ の た め 、 制御装置全体 と し て の発熱量 は大幅 に減少す る 以上 の記述は 、 *癸明 に よ り 、 リ ミ ッ ト ス ィ ッ チ等 の 信号発生手段 と 負荷抵抗 と の直列 回路 の電位変化 ま た は 電流変化を 原始情報 と す る 信号入力 回路 に おい て 、 負荷 抵抗中 に 発生す.る 発熱量 を 減少す る 改良が完成 された こ と を 明 ら か に示す。
The output signals of the signal current detecting means 51, 52, 53, 51a, 52a, 53a provided via 83, 81a, 81b, 81c are read at regular intervals. Yes. When the signal generating means 31 to 33, 31a to 33a are in a non-operating (open circuit) state, the photo couplers 51, 52, 53, 51a and 51a serving as signal current detecting means are provided. Since the 52a and 53a LEDs do not emit light, the input signal is not applied to the level converters 82, 83, 81a, 81b, and 81c, and the signal is read. The low level signal is read by the first and second means 8 and 8a. When the signal generating means 31 to 33 and 31a to 33a are in the operation (closed) state, the signal is low. The LEDs of the photocouplers 51, 52, 53, 51a, 52a, and 53a, which serve as current detection means, emit light, and the signal reading means 8, 8a output level signals. A high-level signal is obtained via the converters 62, 83, 81a, 81b, and 81c, and the signal reading means 8, 8a reads the high-level signal. * In the example Also, since the switching means 1 and la are supposed to operate in synchronization with the signal reading means 8 and 8a, the signal reading means 8 and 8a Since switching means 1 and la are inactive during the period during which the input signal is inactive, the load resistance 2 must be used during periods other than the period during which the input signal is There is no fever in it. Therefore, the amount of heat generated by the control device as a whole is significantly reduced. It clearly shows that the improvement has been completed to reduce the amount of heat generated in the load resistor in the signal input circuit that uses the potential change or current change of the series circuit as the primitive information. .
Claims
1 . 信号発生手段 （ 3 ) と 抵抗 （ 2 ) と の直列 回路 と 、 前記信号発生手段 （ 3 ) と 前記抵抗 （ 2 ) と の接統点 の 電位 を 検 出 す る 信号電圧検 出 手段 （ 4 ) と 、 該信号電圧 検 出手段 （ 4 ) の検 出 す る 信号電位 を 間欠的 に 読 み込 む 信号読 み込 み手段 （ 7 ) と を 有す る 信号入力 回路 に お い て 、 1. A series circuit of a signal generating means (3) and a resistor (2) and a signal voltage detecting means (a voltage detecting means for detecting a potential at a junction between the signal generating means (3) and the resistor (2)). 4) and signal reading means (7) for intermittently reading the signal potential detected by the signal voltage detecting means (4).
前 記 信 号 発生手 段 （ 3 ) と 前 記抵 抗 （ 2 ) と の 直 歹 I 回路 に は 、 前記信号読 み込 み手段 （ 7 ) に 同期 し て動作 す る ス イ ッ チ ン グ手段 （ 1 ) が直列 に 付加 さ れ て な る こ と を 特徴 と す る 信号入力 回路， A switching circuit that operates in synchronization with the signal reading means (7) is provided in the direct I circuit of the signal generation means (3) and the resistance (2). A signal input circuit characterized in that the means (1) is added in series;
2 . 信号発生手段 （ 3 ) と 抵抗 （ 2 ) と の直列 回路 と 、 該 直 列 回 路 に 流れ る 電 流 を 検 出 す る 信 号電 流検 出 手 段 ( 5 ) と 、 該信 号 電流 検 出 手 段 （ 5 ) の 検 出 す る 信 号 電流 を 間欠的 に読 み込 む信号読 み込 み手段 （ 8 ) と を 有 す る 信号入力 回路 に お い て 、 2. A series circuit of the signal generating means (3) and the resistor (2), a signal current detecting means (5) for detecting a current flowing in the series circuit, and the signal In a signal input circuit having signal reading means (8) for intermittently reading a signal current detected by a current detection means (5),
前 記 信号 発生 手段 （ 3 ) と 前 記抵抗 （ 2 ) と の 直 列 回路 に は 、 前記信号読み込み手段 （ 8 ) に 同期 し て動作 す る ス イ ッ チ ン グ手段 （ 1 ) が直列 に 付加 さ れ て な る こ と を 特徴 と す る 信号入力 回路 *
In a series circuit of the signal generating means (3) and the resistor (2), switching means (1) operating in synchronization with the signal reading means (8) is connected in series. Signal input circuit characterized by being added *
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6324786U JPS62179604U (en) | 1986-04-28 | 1986-04-28 | |
| JP61/063247U | 1986-04-28 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO1987006727A1 true WO1987006727A1 (en) | 1987-11-05 |
Family
ID=13223721
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/JP1987/000241 WO1987006727A1 (en) | 1986-04-28 | 1987-04-16 | Signal input circuit |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JPS62179604U (en) |
| WO (1) | WO1987006727A1 (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS52132287A (en) * | 1976-04-28 | 1977-11-05 | Mitsubishi Electric Corp | Input apparatus |
| JPS56145404A (en) * | 1980-03-19 | 1981-11-12 | Omron Tateisi Electronics Co | Input circuit of sequence controller |
| JPS57120107A (en) * | 1981-01-17 | 1982-07-27 | Koyo Denshi Kogyo Kk | Sequence controller |
-
1986
- 1986-04-28 JP JP6324786U patent/JPS62179604U/ja active Pending
-
1987
- 1987-04-16 WO PCT/JP1987/000241 patent/WO1987006727A1/en unknown
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS52132287A (en) * | 1976-04-28 | 1977-11-05 | Mitsubishi Electric Corp | Input apparatus |
| JPS56145404A (en) * | 1980-03-19 | 1981-11-12 | Omron Tateisi Electronics Co | Input circuit of sequence controller |
| JPS57120107A (en) * | 1981-01-17 | 1982-07-27 | Koyo Denshi Kogyo Kk | Sequence controller |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62179604U (en) | 1987-11-14 |
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