JP3507837B2 - Intervention amount control device in positioning device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intervention amount control device for a positioning device for preventing an intervention exceeding a movable range limit of a movable shaft. 2. Description of the Related Art In a position control device constituted by a conventional numerical control device, it is checked whether or not a movement command value is within a movable range of a movable shaft before axis movement. It has a movement command value check and clamp function for changing the movement command value to the movable range limit value, so that even if an incorrect movement command value is input, it does not exceed the movable range limit. However, in the above-described conventional position control device, the movement command value check and the clamping function are performed before the axis movement as described above, so that an intervention operation is performed during the axis movement. When this is done, the movement command value after the intervention will be the sum of the movement command value obtained by the movement command value check and the clamp function plus the intervention amount. There was a problem that it stopped after greatly exceeding. [0004] The inventors of the present invention focus on the technical idea of the present invention in which the allowable value of the intervention amount is obtained in advance at the start of the movement, and the intervention is invalidated when the intervention amount of the intervention processing exceeds the allowable value. Further, as a result of further research and development, the present invention has been achieved which achieves the object of preventing the movable range from being exceeded even if intervention processing is performed. An intervention amount control device for a positioning device according to the present invention is a positioning device for positioning a movable shaft at a commanded target position, and instructs an intervention amount during the movement of the movable shaft. Intervention amount command means, intervention processing means for adding the intervention amount of the intervention amount command means to a previously instructed target position, and an intervention amount allowable value based on a start point, a target position, and a limit position of a movable range at the start of movement of the movable shaft. , An comparing means for comparing the intervention amount added by the intervention processing means and the intervention amount allowable value, and when the intervention amount reaches the intervention amount allowable value, And intervention invalidation means for invalidating the intervention processing of the intervention processing means. The intervention amount control device in the positioning apparatus of the present invention having the above-described structure calculates the intervention amount allowable value from the starting point, the target position, and the movable limit at the start of the movement by the intervention amount allowable value calculating means, and compares it. Is compared with the intervention amount of the intervention amount command means, and when the intervention amount reaches the intervention amount allowable value by the intervention invalidation means, the intervention by the subsequent intervention processing means is invalidated. Is what you do. The intervention amount control device in the positioning apparatus according to the present invention having the above-described operation invalidates the subsequent intervention processing when the intervention amount reaches the intervention amount allowable value, and thus exceeds the movable limit. Even if the intervention processing is performed, an effect of preventing the movement range limit from being exceeded is exerted. Embodiments of the present invention will be described below with reference to the drawings. The intervention amount control device in the positioning device of this embodiment is a positioning device for positioning a movable shaft at a commanded target position as shown in FIG. 1 and FIG. Intervention amount allowable value calculating means 1 for calculating a positive side and a negative side allowable amount from the positive side and the negative side movable limit, and comparing means for comparing the intervention amount by the intervention processing with the positive side and the negative side allowable amount And an intervention invalidating means 3 for invalidating the intervention process when the intervention amount reaches the plus side and the minus side intervention amount allowable values. In the above-described intervention amount control apparatus of the present embodiment, as shown in FIG. 2, a positioning device 4 having this intervention amount control apparatus outputs a position command to a servo unit 5, and the servo unit 5 detects an absolute position. The present invention is applied to a device that controls the position of the movable shaft 72 of the movable unit 7 in consideration of the absolute position of the movable shaft 2 detected by the device 6. The positioning device 4 is constituted by a numerical control device, and as shown in FIG. 2, a microprocessor unit (hereinafter abbreviated as MPU) 41 which mainly performs control calculations including the intervention amount control calculation of the present embodiment, and A ROM 42 storing a control program, a data input device 43 such as a keyboard, and a RAM 44 storing a target position M, a current position R, a movement amount RL, a start position S, an end position E, an intervention amount I, and the like.
And a manual pulse generator 45 for intervention operation and a counter 46. The servo unit 5 is connected to the positioning device 4 and performs a calculation.
PU) 51 and a drive circuit 52 for supplying electric power to the servo motor 71. As shown in FIG. 2, the movable portion 7 includes a servo motor 71 driven by the servo unit 5 and a movable shaft 72 formed by a feed screw mechanically connected to an output shaft of the servo motor 71. A movable table 70 that is moved by the rotation of the movable shaft 72, and a speed detector 73 that detects the moving speed of the movable table 70 and sends a speed feedback signal to the drive circuit 52. The absolute position detecting device 6 is connected to the first resolver 61 via a first resolver 61 mechanically connected to an output shaft of a servomotor 71 and a speed reduction mechanism 63 as shown in FIG. A second resolver 62 and a first phase comparator 64 for detecting a phase angle of the first resolver 61.
A second phase comparison circuit 65 for detecting the phase angle of the second resolver 62, an absolute position calculation circuit 66 for calculating the absolute position of the movable base 70 from the outputs of both, and outputting the calculated absolute position to the MPU 51 of the servo unit 5. , First and second resolvers 6
And a resolver exciting circuit 67 for exciting the first and the second 62. Before the movement is started, the intervention amount allowable value calculating means 1 follows the program shown in FIG. 3 which is stored in the ROM 42 of the position control device 4 in advance. S and the movement end value E are read, respectively.
The movement amount M is calculated from the difference between the movement end value E and the movement start value S read in 03. In step 104, it is determined whether the moving amount M is positive or negative. If the moving amount M is positive as shown in FIGS. 6 and 7A, the process proceeds to step 105, and FIGS. 8 and 9A.
If the result is negative as shown in FIG. If the movement amount M is positive, the difference between the plus side movable limit RP and the movement end value E is calculated in step 105 as shown in FIGS. 6 and 7A and 7B. In addition to calculating the initial plus-side intervention amount allowable amount IP, in step 106, the difference between the movement start value S and the minus-side movable limit RM is calculated to calculate the initial minus-side intervention allowable amount IM. If the movement amount M is negative, the difference between the plus side movable limit RP and the movement start value S is calculated in step 107 as shown in FIGS. 8A and 9B. In addition to calculating the initial plus-side intervention allowable value IP, in step 108, the difference between the movement end value E and the minus-side movable limit RM is calculated to calculate the initial minus-side intervention allowable amount IM. The comparing means 2 and the intervention invalidating means 3
In accordance with the program shown in FIG. 4 stored in the ROM 42 of the position
At 1, the counter value P is read at the counter reading timing corresponding to the command output timing at times t1 and t2 after time t0. As is clear from FIG.
Suppose more intervention has begun. Next, at step 202, the total intervention amount IT is calculated from the sum of the counter value PL from time t1 to time t2 and the counter value P read at step 201. In steps 203 and 204, if the movement amount M is positive and the total intervention amount IT is positive as shown in FIG. 6, the current position R is read in step 205,
In step 206, a plus-side intervention allowable amount IPR, which is the sum of the current position R and the initial plus-side intervention allowable value IP, is calculated. In step 207, the plus-side intervention allowable amount IR is calculated.
The PR is compared with the total intervention amount IT. If the plus-side intervention allowable amount IPR is smaller than the total intervention amount IT, step 208 is performed.
, The intervention amount I is set to P, and conversely, if the plus-side intervention allowable amount IPR is larger than the total intervention amount IT, the intervention process is invalidated if it is possible to continue to permit the intervention, and the intervention limit is invalidated. Set I to zero. If the movement amount M is positive and the total intervention amount IT is negative, as shown in FIG. 7, in step 209, the initial minus intervention allowance I is set as the minus intervention allowance IMR.
If M is set and the allowable amount of negative intervention IMR set in step 210 is larger than the total amount of intervention IT, it is determined that there is a possibility that the operation limit will be exceeded if the intervention is continued, and the intervention process is invalidated. The intervention amount I is set to zero, and the negative intervention amount I
If the MR is smaller than the total intervention amount, the intervention amount I is set to P in step 212. If the movement amount M is negative, it is determined in step 213 whether the total intervention amount IT is positive or negative. If it is positive, as shown in FIG. The capacity IP is set, and the magnitude of the plus-side intervention allowable amount IPR and the total intervention amount IT set at step 215 is determined. When I is set to P, and conversely, the plus-side intervention allowable amount IPR is larger than the total intervention amount IT, the intervention amount I is set to zero as described above. If the moving amount M is negative and the total intervention amount IT is negative, as shown in FIG.
Is read, and in step 218, the initial minus-side intervention allowance IM is added to the current position R to calculate the minus-side intervention allowance IMR. In step 219, the minus-side intervention allowance IMR is compared with the total intervention amount IT. In this case, in step 220, the intervention amount I is set to P, and conversely, the minus-side intervention allowable amount IMR is set to the total intervention amount I.
If it is larger than T, the intervention amount I is set to zero as described above. Next, in step 221, the intervention amount is added to the total intervention amount PL up to the previous time, the counter is reset, and the process ends. The calculation of the command speed in the positioning device 4 is performed in accordance with the program shown in FIG. 5 stored in the ROM 42 in advance. At step 303, the actual remaining movement amount RL, which is the difference between the movement end value E and the current position R, is calculated. Next, at step 304, the intervention amount I is read, and at step 305, the intervention amount I is added to the actual remaining movement amount RL to calculate the command movement amount SL. It is determined whether or not it is zero. If there is a command movement amount ΔL, the command speed Vc is calculated in step 307, and the command speed Vc is output in step 308. If the command movement amount is zero, a command speed Vc = 0 is output in step 309. The intervention amount control device in the positioning apparatus according to the present embodiment having the above-described operation has the intervention allowance amounts IPR and IPR.
By comparing the MR with the total intervention amount IT, the validity and invalidity of the intervention process are controlled. Therefore, in each case, the movable range limits RP and RM are set as shown in FIG. This has the effect of preventing it from being exceeded. The intervention amount control device in the positioning device according to the present embodiment is a numerical control device in which even if an intervention operation such as a handle pulse output is performed by the handle pulse generator 45 during the automatic operation, the end point position by the automatic operation. Does not exceed the limit of the movable range, so that the operation can be performed safely. The above-described embodiments are illustrative for explanation, and the present invention is not limited to these embodiments. Those skilled in the art will recognize from the claims, the detailed description of the invention, and the drawings. Modifications and additions are possible without departing from the technical idea of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing functional blocks of an embodiment of the present invention. FIG. 2 is a block diagram illustrating a hardware configuration of the apparatus according to the embodiment. FIG. 3 is a chart illustrating an intervention allowable value calculation flow according to the embodiment; FIG. 4 is a chart showing an intervention amount control flow according to the embodiment. FIG. 5 is a chart illustrating a command speed calculation flow according to the present embodiment. FIG. 6 is a diagram showing one form of position control in which an intervention operation is performed. FIG. 7 is a diagram showing another form of the position control in which the intervention operation is performed. FIG. 8 is a diagram showing another form of position control in which an intervention operation is performed. FIG. 9 is a diagram showing another form of the position control in which the intervention operation is performed. FIG. 10 is a diagram showing position control in a conventional device. [Description of Signs] 1 Intervention amount allowable value calculation means 2 Comparison means 3 Intervention invalidation means 4 Positioning device 5 Servo unit 6 Absolute position detection device 7 Movable part 41, 51 Microprocessor unit 42 ROM 43 Data input device 44 RAM 45 Manual pulse Generator 46 Counter 52 Drive circuit 61 First resolver 62 Second resolver 64 First phase comparison circuit 65 Second phase comparison circuit 66 Absolute value calculation circuit 67 Resolver excitation circuit 70 Movable table 71 Servo motor 72 Movable shaft 73 Speed detection vessel

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-64-16394 (JP, A) JP-A-61-32108 (JP, A) JP-A-2-250782 (JP, A) JP-A-5-205 241629 (JP, A) JP-A-54-155378 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G05B 19/18-19/46 G05D 3/00-3/20 B23Q 15/00-15/28 B25J 1/00-21/02

Claims (1)

(57) Claims 1. A positioning device for positioning a movable axis at a commanded target position, an intervention amount instruction means for instructing an intervention amount during the movement of the movable axis, and an intervention amount command. Intervention processing means for adding an intervention amount of the means to a previously instructed target position; intervention amount allowable value calculating means for calculating an intervention amount allowable value from a start point, a target position, and a limit position of a movable range at the start of movement of the movable shaft; Comparing means for comparing the intervention amount added by the intervention processing means with the intervention amount allowable value, and invalidating the subsequent intervention processing of the intervention processing means when the intervention amount reaches the intervention amount allowable value. An intervention amount control device in a positioning device, comprising intervention intervention invalidation means.