WO1984001839A1

WO1984001839A1 - Method of returning to origin

Info

Publication number: WO1984001839A1
Application number: PCT/JP1983/000385
Authority: WO
Inventors: Shinsuke Sakakibara; Haruyuki Ishikawa
Original assignee: Fanuc Ltd
Priority date: 1982-10-27
Filing date: 1983-10-27
Publication date: 1984-05-10
Also published as: JPS5977519A

Abstract

System for returning a movable object (TB) to an origin by moving it towards the origin after it has been moved either toward the origin or away from it (+X direction). A dog (DG) is provided at one end of the movable unit (TB) and a machine stationary unit (MC), and a limit switch (LS) is provided at the other. This method comprises the steps of checking whether the limit switch is ON or OFF to discriminate whether the limit switch exists in an origin vicinity range (A II) on the basis of ON or OFF, in an overtravel side range (A I) at both sides of the dog or in a working range (A III), moving the movable unit (TB) toward the origin to a predetermined distance when the limit switch is not in contact with the dog, checking whether the limit switch is in contact with the dog or not by the movement, discriminating whether the limit switch is disposed at the overtravel side (A I) or at the working range side (A II), moving the movable until the limit switch is isolated from the dog when the limit switch is disposed at the overtravel side or in the vicinity of the origin, and moving the movable unit toward the origin when the limit switch is disposed at the working range or isolated from the dog in order to return to the origin.

Description

Specification

Home position return method

Technical field

The present invention relates to an origin return method, particularly, by moving a movable portion of a table and a port of a machine tool in a direction opposite to a predetermined origin return direction, and then moving the movable portion in a direction of origin return. The present invention relates to an origin return method for returning a movable portion to an origin position. Background art

After moving the movable part of the machine tool or robot in the direction opposite to the predetermined home return direction, it is moved in the home direction, and the home return speed is reduced by the generation of a deceleration signal. There is a home position return method in which the moving part is stopped by the first motor rotation signal after the signal is generated. For example, Western history

See p. 438 of the "NC Handbook" published by Nikkan Kogyo Shimbun on May 25, 1992. Fig. 1 is an explanatory diagram of the method of returning to the origin. The limit switch LS force is applied to the machine movable part (table) TB, and the origin is returned near the origin of the machine fixed part MC. Dogs DG are provided. When the home return mode is set in the work area AII on the left side of the limit switch LS card DG DG, the machine movable section TB is rapidly traversed toward the origin. Move with V i. When the limit switch LS reaches the home position near the home position at time and comes into contact with the home position return dog DG, the limit signal LSS force, as shown in FIG. (Highly enormous) Power 0 "(Lowly enormous)

ΟΜΓΙ You. The home return speed is reduced by the falling signal (deceleration signal) of the limit signal LSS. Its to, the time t ₂ to you by Li Mi Tsu door switch LS is Doc 'DG force et al away, is re-Mi Tsu door signal becomes "1 from" 0.尙 At this time, the moving speed is V £. When the limit signal LSS power changes from “0” to “1” (rises), the machine movable section TB moves toward the origin at a speed V £ thereafter, and the rise of the limit signal LSS (origin) (Proximity signal) Stops when the first rotation signal of the motor after the generation of the ORS signal is generated 中, OTA in Fig. 1 is over, trapeel area, 1st error AI is over The trailing area, the second area AII is the area near the origin, and the third area AI is the work area.

Before returning to the home position, the table is moved in the direction opposite to the home position return direction before the table is moved in the home position return direction, and the limit switch LS is moved to the first position. 3 Area (work area) It is necessary to position the AI, and then return to the origin by the method related to Fig. 1 above. For this reason, in the conventional homing method, the direction is opposite to the homing direction.

The table was moved in the specified distance (plus direction) and then returned to the origin by the method related to Fig. 1 above. At this point, if the specified distance is increased, the limit switch LS can be surely positioned at the third area A Ϊ, but the home return time becomes longer. For this reason, generally, the above-mentioned specified distance is set at the limit switch LS regardless of the first, second, and third error ending points, Α Π, and AI, regardless of the displacement area.

OMPI If it moves in the direction of the specified distance plus, the limit distance is set to the minimum distance at which the limit switch LS is positioned at the 3rd area rear AI. However, in the home position return method in which the actuator is moved in the plus direction by a specified distance and then moved in the direction of the origin, c is required for movement. Since there is a response delay between the support and the system for the distribution of the screws, the specified distance c. After the completion of the screw distribution, move toward the origin (minus direction). The table moves in the plus direction by the amount of the delay even if the thread distribution is started. Then, during the movement in the plus direction due to this delay, the limit switch LS is separated from the limit switch LS, and the limit signal LSS power, from \ 0 ,, 1 ", the control device assumes that the origin proximity signal has been generated, and then stops at the position where the first rotation signal is generated as the origin, and malfunctions. When the home switch is requested when the limit switch LS is in the ono-label side area AI, the NC unit issues B with a table. The number of commands required to move the actuator to the point CP in the plus direction by the specified distance L i. The motor and the motor rotate with a predetermined delay, and the generation of fingering noise stops. At this point, the limit switch LS is at the point AP in the figure, that is, the number of command pulses necessary to move the movable part to the command position CP is obtained. Even when the limit switch LS is input to the server circuit, the limit switch LS does not reach the command position CP but is at the point AP.

—On the other hand, the NC unit has a number of commands corresponding to the specified distance L i. If a loss occurs, the homing process shown in Fig. 1 is performed immediately thereafter. That is, c for moving the table TB in the direction of the origin (minus direction). Start the thread distribution calculation and distribute. Input to the circuit. However, the distribution force for moving the table in the minus direction in this way. Even if a pulse is generated, the table moves further in the plus direction due to the delay, and the movement in the plus direction causes the limit switch LS power, away, ing to re-mitt up signal LSS force s ^¾ 0 "or et al. 1". NC unit has limit signal

When the LSS power becomes 0 ", 1", it recognizes that the origin proximity signal has been generated, then determines the position where the 1-rotation signal is generated first as the origin, stops, corrects the origin, and then stops. The recovery operation cannot be performed.

In view of the above, it is an object of the present invention to provide a method of returning to the origin of a movable part such as a machine tool or a port which can reliably return to the origin.

Another object of the present invention is to provide an origin return method that can minimize the moving distance of the movable part in the direction opposite to the origin return direction, thereby shortening the time required for the origin return. is there. Disclosure of the invention

The present invention employs an origin return method in which a movable portion of a machine tool or a robot is moved in a direction opposite to a predetermined origin return direction, and then the movable portion is moved in the origin return direction to return to the original position. Yes, the moving distance of the movable part in the direction opposite to the home return direction can be minimized.

CMFI

, This is an origin return method that can return to the origin. According to the present invention, (a) a dog is provided on the mechanical fixed portion, and a limit switch is provided on the movable portion, which can engage with the dog and the dog. (B) The tape is reset by a home return request. Is moved in the direction opposite to the home return direction by a predetermined distance. (If the limit switch force dog comes into contact after the movement, the limit switch Move the table further in the direction opposite to the home return direction until it is disengaged. (D) Immediately execute the home return processing shown in Fig. 1 after disengagement, and move in (b). If the rear limit switch is not engaged with the dog, the home return process is executed immediately as shown in Fig. 1.

Fig. 1 is a diagram for explaining the conventional origin return method, Fig. 2 is a diagram for explaining the problems of the conventional origin return method, Fig. 3 is a block diagram of an embodiment of the present invention, and Fig. 4 is a process according to the present invention. Best Mode for Carrying Out the Invention

In the automatic operation mode, when the start button (not shown) on the operation panel 1Q1 of the NC device shown in FIG. 3 is pressed, the processor 102 receives the NC data reading device 1 Activate Q3 and read one block of NC data from NC tape 104.o

In accordance with the control program stored in the ROM 105, the aperture sensor 102 determines whether the read NC data is path data, M-, S-, or T. -Determine whether the instruction is a function instruction. If the instruction is an M-, S-, or T-function instruction, these instructions are passed through an interface circuit (not shown) to the machine tool or robot.

__O PI, WIFO Output from the machine, and the following operation completion signal from the machine side

The NC data is read from the NC tape 104 and the same processing is performed.

On the other hand, if the read NC data is path data, the input processor 102 uses the path data to increment the axis incremental values Xi, Yi (2 Calculate as). Then, the processor 102 is calculated from the incremental values X i, Y i and the finger speed F by the following equation.

F X = X F X + Y (l a)

F y = Y iF X + Y (l b)

Velocity components F x in each axis direction, calculates the F y, thereafter seconds (= 1 6 m _S ec) the axis movement distance X of each, to the following equation

Δ X = F X Δ T (2 a

Δ Y = F y-Δ T (2b)

Calculate and store in RAMI06.尙, it is that has been previously stored in the C ⁰ ra over data Note Li 1 0 7 of the non-volatile.

The mouth sensor 102 outputs X, ^ ί ^ every ^ ί Τ seconds. Output to Lus distributor 108. C. Luth distributor 108 is a well-known device based on input data X. Performs a distribution algorithm and distributes it. Generates XCP and YCP, and inputs them to the X-axis drive unit 109 X and Y-axis drive unit (not shown), respectively.

OMPI Move the movable parts of the machine, robot, and kit toward the target position. X-axis drive unit 109 Only X is shown, but the configuration of the Y-axis drive unit is the same as the configuration of the X-axis drive unit It is.

On the other hand, the processor 102 changes the current position Xa, the X-axis direction and the Y-axis direction stored in the RAM 106 every second.

Y a is given by

X aSat X → X (3 a)

Y a ± J Y → Y a (3b)

Update (however, the sign depends on the moving direction). Also, the port processor 102 stores the remaining movement amount in the X-axis direction and the Y-axis direction stored in the RAM 106 every second. Xr and Yr (the initial values of Xr and Yr are the incremental values Xi and Yi, respectively) are given by the following equations.

Χ τ-Δ Χ → Χ r (4 a)

Ύ τ-Δ Υ → Υ (Update 4b. If the movable part reaches the target position,

If X r = Y r = 0 (5) holds, the processor 102 transmits the next NC data.

Reading from NC tape 104 and repeating the above process The above process is repeated, indicating the program end from the NC tape \, M02 " Or indicates a tapeend ^{When ¾M} 30 “is read, a series of NC control ends. 尙, X-axis drive section 103 X is a ha. Distributing ha from pulse distributor 108. Halo XCP is input. Then, the following support and operation are executed, but only the operation of the X-axis drive unit 109 X will be described below.

Distribute loose from commander 1 Q8 (command ° loose)

Each time the XCP power is sent out, the reversible counter RCN1 counts this, and a power EE proportional to the content of the count is generated from the digital-analog converter DAC.

This voltage. The amplifier is amplified by the amplifier AMP, rotates the servomotor M, and the sampler TB is connected to the servo and the motor through the shaft ヅ BS. Drive.

At the same time, rotate the servo and motor M or rotate the rotary encoder and RE. The mouth alien encoder RE is configured to generate a loose FBP every time a predetermined amount of rotation is performed, and to generate a single rotation signal PC every one rotation. Thus, the rotational saddle amount of the thermomotor M and the rotation amount are detected by the rotary encoder RE, and the rotation amount is reversible as a -feed-packs FBP. It is input to the subtraction terminal of the counter RCN1 and subtracts the contents of the counter. The command lure XCP stops and the number of feed hacks equals the number of command lures. When the loose FBP occurs, the content of the reversible counter becomes zero, the motor #M stops its rotation, and completes the passage control or the positioning control. The above is the description of the operation in the automatic operation mode.

O FI On the other hand, when the origin return mode is commanded by operating the buttons on the operation panel 101, the processor 102 returns to the origin return control plug stored in R0M105. Under the control of the room, the home return process shown in FIG. 4 is performed. That is, first

(1) The processor 102 reads the state of the first flip-flop 110a of the interface section 110. 】, 1,,, 0 ”of the limit signal LSS output from the limit switch LS output is the ^first signal of the interface section 110. It is stored in the flip-flop 110a.

(2) After the power is applied, the processor 102 has the limit signal LSS power ^ and ^λ1 depending on the state of the first flip-flop 110a. to determine the force ^¾ 0 "der Luca (Se Tsu if bets state LSS is Ru 1 der) if LSS = ,, 0 Li mitt up scan I Tsu switch LS force;. de, grayed and It is judged that they are in contact with each other, and if LSS =, 1 ", the limit switch LS is the one that exists in the first third area AI, AI [ Then, the following processing is performed.

(3) That is, if L S S =, 1 ", the processor

102 is when the distance between the origin proximity signal generation position and the upper trap is defined as Lo (see Fig. 1).

L 0 + α (α> 0 ) and as a fin click Li main te le values run Ha ⁰ pulse distribution operation described above, the command C. Generates a pulse XCP and moves the table in the plus direction. Where α is the limit switch LS power When it is in one patrol side area AI, the limit switch is necessarily positioned in the second area or the third area by the movement of (L. + a). Value to ensure that

(4) The processor 102 reads the state of the first flip-flop 110a in a short cycle, and each time it outputs the limit signal LSS power 1 ". It is determined ^{whether the} force is zero.

(5) If the result of the determination in step (4) is LSS-,, 1, the processor 102 has the power corresponding to the moving distance (L) force (L o +). Determine which way to go.尙, L = L. + What is lost is actually determined by whether or not the remaining movement amount Xr has become zero.

(6) If L <L0 + α, repeat the processing from step ( ³ ). And LSS = ^¾0 "

If L = L0 + a, the processor 102 determines that the limit switch LS has been in the work area AI from the beginning, and proceeds to step (9). Execute the processing of. In addition, if LSS-O is obtained in the step (determination processing), the processor 102 is set to the limit switch LS in the over-trapper area at the beginning.

Judge that it exists in A I and perform the following processing.

(7) In other words, the initial limit switch LS force-the second

If it exists in A11 (when LSS = ^¾0 "in the step (discrimination processing), or in the processing after step ( ³ ), (Lo + t If the limit switch LS reaches the second area Α before the movement of the

CMPI Direction and Rumadepu B cell Tsu Sa 1 0 2 Ru and LSS = 1 "in the reverse direction generates a command C ° ls e XCP by Ha ⁰ ls e distributor 1 0 &.

(8) By the processing in step (7), if the limit switch LS reaches the work area AII (if LSS = 1 "), the table is closed. Stop .

(9) The mouth sensor 102 outputs the home return order ZRN ί =,, 1 〃) and outputs the second flip-flop of the interface circuit 110. Flop 1 1 Set Ob and set the direction of return to origin. Generates XCP and performs the homing process according to Fig. 1.

Now, flip-flops. FF 1 and FF 2 are initially reset and AND gate AN 1 is open. But c. Command c given by the screw distributor 108. Loose (home position return. Loose) XCP is supplied to RPC 1 through this port, and the operation is the same as described above. Move in the direction (arrow direction). When the table reaches the vicinity of the origin and touches the limit switch LS force dog DG provided on the tape, the limit signal LSS force; w1 "to 0" Open AND gate AN2 and set flip-flop FF1. At the same time, the limit signal LSS resets the first flip-flop 110a, and the set state of the flip-flop is set to the pro- cess. It is read by the sensor 102. As a result, the profile cell Tsu support 1 0 2 Li Mi Tsu door signal LSS force; One that to ^¾ 0 " Identify the octopus and return to origin. Slow down the speed of the loose. Thus, the table moves toward the origin at a low speed, and the U mit switch LS force is restored (from 0 "to 1"). With the one-rotation signal PC generated by the encoder E; ^, set the AND gate AN3; open FF2, and set the reciprocal counter RCN1. Clear the contents and complete the home return.尙, Origin return completion signal ZRE Set the third flip-flop 110c, and the processor 102 sets the third flip-flop 7 ° 1 10 Read the setting status of c and return to origin. Stops the generation of Lus XCP.

As described above, according to the present invention, the table movement in the direction opposite to the home return direction is controlled in accordance with the relative positional relationship between the limit switch and the dog at the time of the home return command. If there is a limit switch in the gap between the area and the patrol side, make sure that the limit signal goes from 0 to \ 1 ", in other words. B limit switch

After confirming that the L S was securely positioned in the work area, it was attempted to move in the direction of returning to the home position, so that the home position could be returned reliably. In addition, since the moving distance in the direction opposite to the home return direction is made as small as possible, the home return time can be reduced.

Industrial applications

As described above, the present invention is effective because it can surely return the movable parts of the machine tool, the mouthpiece and the kit to the origin in a short time.

C FI

Claims

The scope of the claims

1. After moving the movable part in the direction opposite to the predetermined home return direction, move it in the home direction and return to the home position. In the home return method, either the movable part or the machine fixed part. A switch is provided on one side, and a limit switch is provided on the other side, and the limit switch is used when a home position return request is made using a signal from the limit switch. Step to determine whether the contact is in contact with the force or the contact, and the contact is in contact with the contact. If the limit switch is in contact with the contact, the origin return direction Step of moving the movable part in the opposite direction to the limit switch force during the movement of the predetermined distance; To the limit switch, the step to move it farther away, Tsu DOO scan I Tsu homing method switch is characterized that you have a scan STEP for homing to the movable portion is moved to the home direction after leaving Ri Da Yo.

2. If the limit switch is in contact with the dog 'when a home return request is made, move the movable part in the direction opposite to the home return direction until the limit switch force is released. The origin return method according to claim 1, wherein the movable portion is moved and the movable portion is moved in a direction of the origin after the limit switch is separated from the origin to return to the origin.

3. When the limit switch comes into contact with the dog during the movement of the predetermined distance, after the movement of the predetermined distance is completed, the movable portion is moved in the direction of the home position to return to the home position. Features The method of claim 1, wherein the return to origin is performed.

4. The predetermined distance is the limit switching force due to the movement in the direction of return to the origin; Doc, the position farther away: ^ L The distance from the trapezoidal area to L ,

An origin return method according to claim 1 or claim 3, wherein L 0 + (α> 0).

Οί -'- ΡΙ