JPS586164B2 - The best way to do it - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fixed position stop control device that improves the apparent stopping accuracy by detecting the low speed of a moving body before it stops and changing the stop command point.

In general, when a moving object moving along a guide such as a rail is stopped at a fixed position with high precision, the moving speed of the moving object before stopping is reduced to a low speed such as several times the rated speed, and the load on the moving object at that low speed is It is necessary to suppress the speed fluctuation rate due to fluctuations, etc. to a fluctuation value determined by the required stopping accuracy.

Therefore, in order to improve the stopping accuracy, a high-performance, expensive drive control device with a small rate of speed fluctuation is required as a drive control device for a moving body.

Conventionally, a so-called inching correction method has been adopted as an inexpensive method for improving stopping accuracy, in which after stopping at a fixed position, if the moving object falls outside the required accuracy, the moving object is moved a small distance again to bring it back to the required accuracy.

This invention provides a method for stopping a moving body having a speed control device that does not satisfy the above-mentioned speed fluctuation rate requirement within the required stopping accuracy without making any corrections after stopping. A stop control device is provided.

The details will be explained below by giving an example.

Now, if the deceleration α when stopping from a low speed is constant, and the low speed is V, the stopping distance 1 will be 1-2/2α.

Therefore, when the low speed V changes, j changes in proportion to its square.

This invention uses the method described below to detect a dog or small dog at a low speed V step by step. If ■ is large, the stopping distance will be long and the vehicle will be stopped early, and if ■ is small, the stopping distance will be short. This is a method that attempts to stop at a fixed position by stopping late.

In other words, in Fig. 1, the low speed V fluctuates in the range of V1 to v4, and when V2<V<Vl, the L2 point is V3. shall be stopped at L4.

Here, each point of L2, L3tL4 is the target stopping position L
These are points whose distances from X are l"!tl"ltl'4, respectively.

Now, the average speed at point L2 is (V1-V2)/2+the average speed at point L3 is (V2-Vs)/2, the average speed at point L4 is (v3-v4)/2e, and when the speed is V The stopping distance l is as described above (/=V2/2α, so the above l”
2tl''3tl'4 are respectively expressed as follows.

Next, a method for determining the value of the low speed V into the above three speed ranges will be explained with reference to FIG.

A sensor for detecting the position of a moving object, in which a minute movement amount detector 1 using a pulse transmitter is attached to a moving object (not shown), and a pulse train a generated from the pulse transmitter is separately provided when the moving object moves. The point where A operates (Lo in Figure 1)
) is counted by pulse counter 2.

This is done by opening AND gate 41 based on the output from sensor A.

Note that l1 to j5 in FIG. 1 are determined as follows.

In other words, the distance from point L0 at which the counter 2 starts counting until the counter 2 counts and amplifies the first preset value X1 is the distance l1 from L0 to L1.
The above X1 value is selected according to reality so that

Similarly, the second preset value X2 is set according to the distance l2 from L0 to L2, the third preset value X3 is set according to the distance l3 from L0 to L3, and the third preset value X3 is set according to the distance l4 from L0 to L4. Select the fourth preset value X4.

The above l1 is a region for measuring whether the low speed V is in V2<V≦V1 v3<VNV2 (4≦V<V3), and j1 is expressed as follows.

l1-lo-X1 Here, /o (minute movement amount) is a unit movement amount, and is usually selected to be about 1/10 of the fixed position stop width (m).

Also, select X1 to be around 10. Further, assuming that the lengths of the operating regions of sensors A and B are equal to each other l5, and when the fixed position stop width is m, it is necessary that 15>l1+12+m/2.

In other words, l1 is the distance necessary to determine what kind of speed the low speed V is as described above, and l6 is
In the case of v1>V2>v3>V4, it is the distance required to stop at the average speed (=V1-V2/2) when judged to be the highest speed, and m/2 is the distance required to stop the stopping point within the fixed position stopping width. The sum of these is the minimum required width within the sensor operating area.

Note that j5-(l1+l'2+m/2) is the distance from determining low speed to actually starting the stopping operation (Ll~L2
This can be determined depending on the responsiveness of the device, the low speed of the application, etc.

Naturally l2:l5-m/2-l'2, l3=l5-
m/2-l''3tl4=l5-m/2-l64 (The fixed position stop width is detected as the area where both sensors A and B operate, and m≧Vl2V22.

). Further, the pulse counter 2 is XI,
You can preset four arbitrary values of X2, X3, and X4, and the contents of the count are the above set values
The output signals C1 to C4 are outputted when the respective values are reached.

The above X1 to X4 are respectively X1=71/lo and X2=1
2/lo, X3=l3/1o, X4=l4/10.

On the other hand, the timers T1 and T2 are assumed to measure time when the sensor A operates as shown in FIG. 2, that is, from the Lo point in FIG. If it is set so that l1=lOX1, the following condition is satisfied when the counter output C1 is output at point L1 in FIG. 1, that is, in FIG.

However, the time-up output of T1 is assumed to be t1, and the time amplifier output of t2 is assumed to be t2.

) 1) When V>V2, both t1 and t2 are off (time 7 is not stopped). ■) When V2≧V>V3, t1 is on and t2 is off.

m) When v≦v3, both t1 and t2 are on.

The above conditions are determined by the discriminating circuit 3, and 1), II), m
), the discrimination outputs d1, d2, and d3 are output respectively.

The above outputs d1, d2, d3 cause the above L2,
Counter output signals C2 and C which are detection signals of L3 and L4
3 and C4 are selected by the AND gates 42, 43, 44 and the OR gate 52, and the stop signal e is outputted according to the logical formula e-d1.C2+d2.C3+d3.C4.

By the above method, the stop signal e is determined by the conditional expression I when the low speed V is
) is the L2 point, ■) is the L3 point, and ■) is the L4 point.
It will be outputted at each point, and V will be output from V1 to v4
This means that the stopping position will not change significantly even if it fluctuates within the range of .

If the moving object moves in the opposite direction to that shown in FIG. 1, the same effect can be obtained by replacing sensor A with sensor B.

Further, in the above explanation, the V is divided into three regions, but the same effect can be obtained by dividing it into two or four regions.

The method described above reduces the apparent speed fluctuation range and can improve stopping accuracy.

This system also has the advantage that when the stopping distance changes due to a change in the deceleration α, the stopping point can be easily changed by changing the settings of X2, Xs, and X4.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the relationship between speed and stop command position, and FIG. 2 is a control block diagram showing an embodiment of the present invention. In the figure, 1 is a minute movement amount detector, 2 is a count, and 3 is a minute movement amount detector.
is a discrimination circuit, T1 and T2 are timers, 41 to 44 are AND gates, 51 and 52 are OR gates, and A and B are sensors.

Claims (1)

[Claims] 1 A detector that is attached to a moving body and generates a detection pulse every time it moves a minute amount of movement.The amount of movement is measured by counting the detection pulses from this detector from a predetermined position before the fixed position where it should be stopped. A detection counter includes a determination circuit that determines the speed of the moving body before it stops by measuring the time required when the counter detects a predetermined amount of movement using a timer, and based on the speed determined by this determination circuit. Fixed position stop control device that changes the stop command point.