JPS5980188A - Overload preventing device - Google Patents

Overload preventing device

Info

Publication number
JPS5980188A
JPS5980188A JP57187462A JP18746282A JPS5980188A JP S5980188 A JPS5980188 A JP S5980188A JP 57187462 A JP57187462 A JP 57187462A JP 18746282 A JP18746282 A JP 18746282A JP S5980188 A JPS5980188 A JP S5980188A
Authority
JP
Japan
Prior art keywords
motor
overload
current value
signal
current
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP57187462A
Other languages
Japanese (ja)
Inventor
Akira Ogawa
明 小川
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toshiba Corp
Original Assignee
Toshiba Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Toshiba Corp filed Critical Toshiba Corp
Priority to JP57187462A priority Critical patent/JPS5980188A/en
Publication of JPS5980188A publication Critical patent/JPS5980188A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
    • H02H7/08—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for dynamo-electric motors
    • H02H7/085—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for dynamo-electric motors against excessive load

Landscapes

  • Control Of Electric Motors In General (AREA)
  • Protection Of Generators And Motors (AREA)

Abstract

PURPOSE:To enable to effectively protect a motor and a controller by operating current limiter when the current flowed to a motor exceeds the set value or larger for the set period or longer. CONSTITUTION:A servo controller 9 supplies a current (c) of the prescribed direction to a motor 7 in response to the deviation between a position feedback signal (a) and a movement command signal (b). A motor current detector 11 detects the motor current (c) and a forward current comparator 13 and a reverse current comparator 15 respectively output a forward overload signal (f) and a reverse overload signal (j) when the motor current signals become forward overload reference current value (e) and reverse overload reference current value (h) or higher. An operation timer 16 applies a time out signal to an operation instruction unit 17 when the signal (f) or (j) is inputted at the set time. In this manner, a current limiter 18 suppresses the motor current.

Description

【発明の詳細な説明】 〔発明の属する技術分野〕 本発明は自動ブロービング装置におけるプローバーの上
下動の位置制御に用いたＤＣモータ及びサーボ制御装置
の過負荷における破損防止を行なう装置に関するもので
ある。DETAILED DESCRIPTION OF THE INVENTION [Technical field to which the invention pertains] The present invention relates to a device for preventing damage due to overload of a DC motor and a servo control device used for position control of the vertical movement of a prober in an automatic probing device. be.

〔従来技術とその問題点〕[Prior art and its problems]

自動ブロービング装置において、ブーローパーを被検査
物の測定ポイントに接触成らしめるためにプローバーあ
るいは被検査物を乗せた資料台のどちらかを上下動させ
る必暮がある。又この上下動はプローバーと測定ポイン
トの完全な導通を支えると同時に被検査物に必要以上に
プローバー接触によるダメージを与えないようにするた
め、高い精度が要求され、ＤＣモータとサーボ制御装置
とを用いたものが考えられるようになった。ここで問題
になったのが何らかの異常により過負荷を生じたときの
モータ及び制御装置をいかに保饅するかということであ
る。そこで従来はこれの対策として第１図に示す様にモ
ータ（１）と直列に過負荷継電器（２）等を入れ、異常
時には発熱子（４）が発熱しバイメタルを介して接点（
５）を開放し回路を遮断する様にしていた。しかしこの
欠点として次のことが考えられる。In an automatic probing device, in order to bring the probe roper into contact with the measurement point of the object to be inspected, it is necessary to move either the prober or the document table on which the object to be inspected is placed up and down. In addition, this vertical movement supports complete conduction between the prober and the measurement point, and at the same time requires high precision to avoid unnecessary damage to the test object due to contact with the prober. I can now think of what I used. The problem here is how to protect the motor and control device when an overload occurs due to some abnormality. Conventionally, as a countermeasure against this, an overload relay (2) or the like is installed in series with the motor (1) as shown in Figure 1, and in the event of an abnormality, the heating element (4) generates heat, which is then passed through the bimetal to the contact (
5) was opened to cut off the circuit. However, the following drawbacks can be considered.

■　作動の応答時間が遅い、又不安定でモータと制御装
置の完全な保護が難しい。さら処機械的ムリがかなり長
い間継続するため機械をも毀すおそれがある。■ Operation response time is slow and unstable, making it difficult to completely protect the motor and control device. Since the mechanical strain continues for a considerable period of time, there is a risk of damaging the machine.

■　メカ接点による回路遮断をするので接点の焼き付き
を起こすおそれがあり信頼性が悪い。■ Since the circuit is interrupted by mechanical contacts, there is a risk of the contacts burning out, resulting in poor reliability.

〔発明の目的〕[Purpose of the invention]

この発明は上述した従来装置の欠点を解決するもので、
保護動作が作動する条件としてのモータに流れる電流値
とこの電流値が継続して流れる時間とを自由にそして精
度良く設定できるので、確実にモータ及び制＃装置を保
→することができる。This invention solves the above-mentioned drawbacks of the conventional device.
Since the value of the current flowing through the motor as a condition for activation of the protective operation and the time period during which this current value continues to flow can be freely and accurately set, the motor and the control device can be reliably maintained.

又制御装置内に電流制限器を組み込みこれを作動させて
モータに流れる電流を連続通電可能な電流値まで押えて
しまうものであって動作にムリがなく信頼度が高い等の
ことを特徴とする過負荷防止装置を提供することを目的
とする。In addition, a current limiter is installed in the control device and activated to suppress the current flowing to the motor to a current value that allows continuous energization, and is characterized by smooth operation and high reliability. The purpose is to provide an overload prevention device.

（４）発明の概要 不発゛明は例えば第２図に示すように上下動機Ｐｇ（６
）はＤＣモータ（７）と位置検出器（８）とサーボ制御
装置（９）から成り、この制御装置は位置フィードバッ
ク信号（ａ）を位置検出器から受け、移動指令信号四を
外部よシ受けることによりモータに適時、適当な電流量
を方向を定め電流ｆｃ）を流しサーボ制御を行なってい
る。ここでこの機構に何んらかの異常を生じモータに過
負荷が加わったとき、電流は正常時には流れｆｒｂモー
タ及び制御装置を襞すａ！な大きな１７（流が連続的に
流れ様とする。そこでこの様な状況が発生したとき強制
的にこの電流を連続通電でモータ及び制御装置を殻さな
い電流値まで押えよ２とするのが本発明の過負荷防止袋
＃（１ｏである。(4) Outline of the invention The invention is, for example, as shown in FIG.
) consists of a DC motor (7), a position detector (8) and a servo control device (9), which receives a position feedback signal (a) from the position detector and a movement command signal (4) from the outside. As a result, servo control is performed by passing an appropriate current amount and direction to the motor at the appropriate time (current fc). Here, when some kind of abnormality occurs in this mechanism and an overload is applied to the motor, the current that normally flows flows through the frb motor and control device. 17 (current flows continuously. Therefore, when such a situation occurs, it is recommended to forcibly keep the current flowing continuously to a current value that does not damage the motor and control device.) Overload prevention bag # (1o) of the present invention.

そこで本発明の装置について具体的に述べるとモータＶ
Ｃ流れる電流をモータ電流検出器（１υによって検出し
てこれを数値化し、数値１（ｄ）を出力する。Therefore, to specifically describe the device of the present invention, the motor V
The current flowing through C is detected by a motor current detector (1υ), converted into a numerical value, and outputted as a numerical value 1(d).

この数値はデジタル値であってもアナログ値であっても
かまわない。順方向過負荷基ｆｐ、電流値発生器（１２
）はモータの順方向動作に対する過負荷発生時にモータ
に流れる電流に相当する電流値として数値２を出力する
。ここで数値１と数値２が順方向電流比較器（Ｉ３）に
入力され、数値１と数値２とが比較される。数値１≧数
値２のとき順方向過負荷信号（ｆ）を出力し、数値１〈
数値２のとき順方向正常負荷信号（ｇ）を出力する。凍
た同様に逆方向過負荷基準電流値発生器（１４）けモー
タの逆方向ｒａｈ作に対する過負荷発生時にモータに流
れる電流に相当する電流値として数値３を出力する。This numerical value may be a digital value or an analog value. Forward overload base fp, current value generator (12
) outputs the numerical value 2 as a current value corresponding to the current flowing through the motor when an overload occurs for forward operation of the motor. Here, numerical values 1 and 2 are input to the forward current comparator (I3), and numerical values 1 and 2 are compared. When numerical value 1 ≧ numerical value 2, forward overload signal (f) is output, and numerical value 1 <
When the value is 2, a forward normal load signal (g) is output. Similarly to freezing, the reverse direction overload reference current value generator (14) outputs the numerical value 3 as a current value corresponding to the current flowing through the motor when an overload occurs for reverse direction RA operation of the motor.

ここで、数値１・と・数値３力ｊ逆方兜電流比較器（１
ツに入力される。数値１≧数値３のとき逆方向正常負荷
信号（ｊ）を出力Ｕ７、数値Ｔ＜ｌ’値３のとき逆方向
正常負荷信号（ｋ）を出力する。そこで順方向又は逆方
向の過負荷信号が作動タイマ＋１ｆ）に入力されるとタ
イムが起動さね設定時間経過後タイムアウト信号（ホ）
が出力される。しかし起動された設定時間経過途中で１
喰方向又は逆方向の正常負荷信号が該タイマに入力され
るとタイマー動作は中［トされ初期状態に戻どされる。Here, numerical value 1 and numerical value 3 force j inverse helmet current comparator (1
inputted into TS. When numerical value 1≧value 3, a reverse normal load signal (j) is outputted U7, and when numerical value T<l' value 3, a reverse normal load signal (k) is output. Therefore, when a forward or reverse overload signal is input to the activation timer (+1f), the timer will start. After the set time elapses, a timeout signal (e) will be activated.
is output. However, 1
When a normal load signal in the feeding direction or in the reverse direction is input to the timer, the timer operation is stopped and returned to the initial state.

従って儂負荷の状態が設定時間以上継続されないとタイ
ムアウト信号が出力しないことになる。時間の設定は過
負荷の状態の電流がモータに連続的に流れたときモータ
及び制御装置が殻されない時間の範囲で行なわれる。Therefore, the timeout signal will not be output unless the state of my load continues for the set time or longer. The time is set within a time range in which the motor and control device are not affected when an overload current flows continuously through the motor.

タイムアウト信号が作動指令器、（１ηに出力されると
作動指令信号（ｎ）が出力され、外部より　’Ｊ上セツ
ト号（０）が人力されるまで指令信号は出力したまま保
持される。作動指令信号がサーボ制御装置内に有る電流
制限器に出力式れている閾電流制限器が作動し、モータ
に流れる電流を連続通ばしてもモータ及びｉｌｌ制御装
胎を毀さない電流値まで押える様に働く。When the timeout signal is output to the operation command device (1η), the operation command signal (n) is output, and the command signal remains output until the 'J upper set number (0) is manually input from the outside. The threshold current limiter, in which the command signal is output to the current limiter in the servo control device, operates and the current reaches a value that does not damage the motor and the ill control device even if the current flows continuously through the motor. Works like it's holding it down.

〔発明の幼果〕[The young fruits of invention]

本発明によシ異常が発生してメへ負荷になってもモータ
及び制御装ｖｆ：確実に保護することが可能となった。According to the present invention, even if an abnormality occurs and a load is placed on the motor, the motor and control device vf can be reliably protected.

又従来であれば移動機構のストロークエンドリミット、
スイッチのようなものを取シ付けて操作上でリミットま
で移動したときに停止させる／こめの復雑な操作や余分
な回路が必要だったが、こうし／ヒものを使わなくても
よくなった。Also, in the past, the stroke end limit of the moving mechanism,
Installing something like a switch to stop the system when it reaches the operational limit required complicated operations and extra circuits, but now there is no need to use such devices. Ta.

〔発明の実施例〕[Embodiments of the invention]

本発明は自動プロービング装置のプローバーの上下！０
装置Ｗに用いたＤＣモータ及びサーボ制御装置の過負荷
防止のために開発したものである。The present invention is the top and bottom of the prober of automatic probing equipment! 0
This was developed to prevent overloading of the DC motor and servo control device used in device W.

始めに自動プロービング装置ｇについて簡単に説明する
と、第３図の様に被検査物１１！Ｊが資料台−瀾の上に
装置され、ボジショニングテーブルＣυにより検査ポイ
ントの位置決めを行なう。プローバー（２２１は上下移
動機構１２３に取シ付いており上下移動することにより
プローバーが被検査物の検査ポイントに接触し検査を可
能成らしめるものである。そして上下移動機構はプーリ
１１２４）プーリ２１２５１ベルト０ｂｌＤＣモータＣ
７）位置検出器（２）による駆動機構とこれらをドライ
ブするサーボ制御装置（ハ）Ｋよってなっておシ、上下
移動を行なうことができる。以上から自動プロービング
装着が成っている。そこで上下動機構に過負荷が生じた
ときモータ及びサーボ制御装置を確実に保持するための
過負荷防止装置（至）について説明する。過負荷防止装
置はモータに流れる電流を検出して、この電流が設定し
た電流値以上連続的に１設定した時間を越えて流れたと
きにサーボ制御装置内の電流制限器を作動させ電流を強
制的に連続通電しても機構やモータ、サーボ制御装置を
毀さない電流値まで押えるものである。First, to briefly explain the automatic probing device g, as shown in FIG. 3, an object to be inspected 11! J is installed on a document stand, and inspection points are positioned using a positioning table Cυ. Prober (221 is attached to the vertical movement mechanism 123, and by moving up and down, the prober comes into contact with the inspection point of the object to be inspected, making inspection possible.The vertical movement mechanism is a pulley 1124) Pulley 21251 Belt 0blDC motor C
7) It is possible to move up and down by the drive mechanism using the position detector (2) and the servo control device (c) K that drives these. The automatic probing installation consists of the above. Therefore, an overload prevention device for reliably holding the motor and servo control device when an overload occurs in the vertical movement mechanism will be described. The overload prevention device detects the current flowing through the motor, and when this current continues to exceed a set current value for more than a set time, it activates the current limiter in the servo control device to force the current. It is designed to suppress the current to a value that does not damage the mechanism, motor, or servo control device even if it is continuously energized.

本装置が保護動作を行なう条件と々るモータの過負荷電
流値及びその電流値が継続して流れる時間の設定につい
ては次のごとく決められる。電流値についてはモータ及
びサーボ制御装置の定格電流値内として正常動作時には
あ″！シ継続して流れない値がよい。時間については先
に設定した電流値が正常動作時に継続して流れる時間の
最大値よシ十分余裕をもって定めることが必要である。The conditions for the protective operation of this device to be set for the overload current value of the motor and the time during which the current value continues to flow are determined as follows. The current value should be within the rated current value of the motor and servo control device, and should be a value that does not flow continuously during normal operation.As for the time, the current value set earlier should be within the time period during which the current value continues to flow during normal operation. It is necessary to set the maximum value with sufficient margin.

すなわち正常動作時に本装置が作動しないように、異常
が発生したときには即作動する様にと設定するというこ
とである。本装置の保護動作を解除させるには外部よシ
リセット信号を入れることが必要でそれまでは保護動作
を保持する。そこで過負荷になった原因を取り除いた後
、リセット信号を入力すれば元の状態に復帰する。In other words, the device is set so that it does not operate during normal operation, but so that it immediately operates when an abnormality occurs. To release the protective operation of this device, it is necessary to input an external reset signal, and until then the protective operation is maintained. After removing the cause of the overload, inputting a reset signal will restore the original state.

〔発明その他の実施例〕[Invention and other embodiments]

本発明の過負荷防止装置はＤＣモータ及びサーボ制御装
置を用いた位置出し機構の過負荷を防止するためのもの
であり、ＤＣモータ及びサーボ制御装置を使った装置全
てに使用することはもちろんであるが、ＡＣモータやソ
レノイドのように電流を流し駆動するものであればこれ
らについても応用することができる。但しＡＣ電流を流
す場合については電流検出はＡＣ１ｌｊ流の実行値で検
出する必要がある。The overload prevention device of the present invention is for preventing overload of a positioning mechanism using a DC motor and a servo control device, and can of course be used for all devices using a DC motor and a servo control device. However, it can also be applied to AC motors and solenoids as long as they are driven by flowing current. However, when an AC current is passed, the current must be detected using the actual value of the AC1lj current.

又使用方法についてみれば本来の目的は過負荷防止とい
うことであるが、正常動作の中にあっても本装置電流制
限動作の作動条件としてのモータに流れる電流値とその
電流値が継続して流れる時間とを適当に設定してこの条
件がととのったらモータに流す電流を適当な電流値に制
限するという使い方も出来る。Regarding the method of use, the original purpose is to prevent overload, but even during normal operation, the current value flowing through the motor and that current value are continuous as the operating condition for the current limiting operation of this device. It is also possible to set the current flowing time appropriately and, when this condition is met, limit the current flowing through the motor to an appropriate current value.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は従来例を示す図、第２図は本発明のブロック図
、＠３図は本発明の一実施例を示す図である。 （１１）・・・モータ電流検出器　（ＩＱ・・・順方向
過負荷基準値発生器αｊ・・・順方向比較器　　Ｉ・・
・逆方向過負荷基準値発生器１！１９・・・逆方向比較
器　　１１６）・・作動タイマ　（Ｉ７）・作動指令器
０υ・・電流制限器FIG. 1 is a diagram showing a conventional example, FIG. 2 is a block diagram of the present invention, and FIG. 3 is a diagram showing an embodiment of the present invention. (11)...Motor current detector (IQ...Forward overload reference value generator αj...Forward comparator I...
・Reverse direction overload reference value generator 1!19...Reverse direction comparator 116)...Activation timer (I7)・Activation command 0υ...Current limiter

Claims (1)

【特許請求の範囲】[Claims] ＤＣモータとサーボ制御装置とを用いて位置制御を行な
い過負荷を生じたときに、モータと制御装置とを過電流
によって破損するのを防止する過負荷防止装置において
、モータに流れる電流値を検出するモータ電流検出器と
、モータが順方向に動作していて過負荷となったときの
電流値に相当する基準電流値を発生する順方向過負荷基
準電流値発生器と、モータ検出電流値と順方向過負荷基
準電流値とを比較して、順方向のモータ検出電流値が順
方向過負荷基準電流値よシも大きい時に過負荷信号を出
力し、小さい時に正常負荷信号を出力する順方向比較器
と、モータが逆方向に動作していて過負荷と々ったとき
の電流値に相当する基準電流値を発生する逆方向過負荷
基準電流値発生器と、モータ検出電流値と逆方向過負荷
基準電流値とを比較して、逆方向のモータ検出電流値が
逆方向過負荷基準電流値よりも大きい時に過負荷信号を
出力し、小さい時に正常負過信号を出力する逆方向比較
器と、順方向又は逆方向の過負荷信号を受はタイマが起
動し、正常負過信号を受けてそのタイマーがリセットし
、タイマが起動された後、設定時間の間リセットされず
経過するとタイムアウト信号を出力する作動タイマーと
、タイムアウト信号を受けると作動指令信号を出力し、
そして外部からリセット信号を受けその指令信号の出力
を取シやめる作動指令器と、サーボ制御装置内に組み込
むことによりモータに流す電流を連続通電可能電流値ま
で制限するだめの電流制限器とを具備したことを特徴と
する過負荷防止装置。An overload prevention device that prevents damage to the motor and control device due to overcurrent when position control is performed using a DC motor and servo control device and an overload occurs, detects the value of the current flowing through the motor. a forward overload reference current value generator that generates a reference current value corresponding to the current value when the motor is operating in the forward direction and becomes overloaded; Forward direction that compares the forward direction overload reference current value and outputs an overload signal when the forward direction motor detection current value is larger than the forward direction overload reference current value, and outputs a normal load signal when it is smaller. a comparator, a reverse overload reference current value generator that generates a reference current value that corresponds to the current value when the motor is operating in the reverse direction and overloads, and a reverse direction overload reference current value generator that generates a reference current value that corresponds to the current value when the motor is operating in the reverse direction and is overloaded, and a A reverse comparator that compares the overload reference current value and outputs an overload signal when the reverse motor detection current value is greater than the reverse overload reference current value, and outputs a normal overload signal when it is smaller. When a forward or reverse overload signal is received, the timer is activated, and when a normal overload signal is received, the timer is reset. After the timer is activated, if it is not reset for a set period of time, a timeout signal is generated. An operation timer that outputs an operation command signal, and an operation command signal when it receives a timeout signal.
It is equipped with an operation command device that receives a reset signal from the outside and stops outputting the command signal, and a current limiter that is incorporated into the servo control device to limit the current flowing to the motor to a current value that can be continuously energized. An overload prevention device characterized by:
JP57187462A 1982-10-27 1982-10-27 Overload preventing device Pending JPS5980188A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP57187462A JPS5980188A (en) 1982-10-27 1982-10-27 Overload preventing device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP57187462A JPS5980188A (en) 1982-10-27 1982-10-27 Overload preventing device

Publications (1)

Publication Number Publication Date
JPS5980188A true JPS5980188A (en) 1984-05-09

Family

ID=16206495

Family Applications (1)

Application Number Title Priority Date Filing Date
JP57187462A Pending JPS5980188A (en) 1982-10-27 1982-10-27 Overload preventing device

Country Status (1)

Country Link
JP (1) JPS5980188A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62171479A (en) * 1985-06-03 1987-07-28 ハイデルベルガ−　ドルツクマシ−ネン　アクチエンゲゼルシヤフト Method for controlling at least one of motors of offset printer
DE10115480B4 (en) * 2000-08-30 2005-08-25 Mitsubishi Denki K.K. Protective device for electric power steering device
JP2019064819A (en) * 2017-10-04 2019-04-25 榎本ビーエー株式会社 Method of controlling conveyor and conveyor

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62171479A (en) * 1985-06-03 1987-07-28 ハイデルベルガ−　ドルツクマシ−ネン　アクチエンゲゼルシヤフト Method for controlling at least one of motors of offset printer
DE10115480B4 (en) * 2000-08-30 2005-08-25 Mitsubishi Denki K.K. Protective device for electric power steering device
JP2019064819A (en) * 2017-10-04 2019-04-25 榎本ビーエー株式会社 Method of controlling conveyor and conveyor

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