JPS61100610A - Apparatus for detecting position and speed of converyor mechanism - Google Patents

Abstract

PURPOSE:To detect the position and speed of a conveyer mechanism with high accuracy, by moving a light detector along a slit plate with the movement of the conveyer mechanism and taking out positional information and speed information. CONSTITUTION:A slit plate 5 is provided so as to be fixed to a rail 3 in parallel and, at the same time, a detector 6 for detecting the slit of the slit plate 5 is provided to a moving side conveyer mechanism 11 to detects the position and speed of the moving side detector 6 to the fixed side slit plate 5. By this method, the primary factor of a position detecting error such as the play of a detection gear or the slip between the rail 3 and a wheel 2 is removed and the detection of a position and a speed generating no measuring error can be realized with high accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a device for detecting the position and stacking of a transport mechanism moving on a rail.

[Technical background of the invention and its problems] In general, when detecting the position and speed of a transport mechanism moving on a rail, conventionally a rotary encoder or a synchronizer is used to detect the position and speed of a transport mechanism moving on a rail. A detector such as a resolver or the like was installed to detect position and speed.

However, this detection method has the problem that the detected position information contains errors due to slippage between the wheels and the rails and play in the gear to which the detector is attached, making it impossible to accurately detect position and speed.

[Object of the Invention] An object of the present invention is to provide a device that can detect the position and speed of a transport mechanism with high precision.

[Summary of the Invention] For this reason, the present invention provides a slit plate along the rail on the fixed side, and a photodetector is attached to the transport mechanism on the moving side, so that as the transport mechanism moves, the slit plate is disposed along the rail. It is characterized in that position information is extracted by moving the photodetector along the slit plate, and speed information is further extracted by detecting the time at which the photodetector passes between two points.

[Embodiment of the invention] FIG. 1 shows a mechanical diagram of a position/speed detection device for a transport mechanism according to an embodiment of the invention. It is placed freely. A wheel drive motor 4 is connected to one of the axles 2 via a gear. A slit plate 5 having parallel slit grooves is disposed on the stationary side rail 3, and a detector 6 is attached to the moving side transport mechanism 1 across the slit plate 5.

FIG. 2 shows a partially enlarged view of the slit plate 5. The slit plate 5 has a slit 51 for detecting the origin position and slits 52 for detecting each position at minute regular intervals.

FIG. 3 shows a configuration diagram of a detector 6 fixed to the transport mechanism 1 side across the slit plate 5. On one wall sandwiching the slit plate 5, there is a light emitting element 6 for detecting the slit 51.
! A light emitting element 62 for detecting the slit 52 is fixed to the other wall, and a light receiving element 63 for detecting the slit 51 and a light receiving element 64 for detecting the slit 52 are fixed to the other wall.

FIG. 4 shows a calculation block diagram in which the position signal b and speed signal C are calculated by the calculation unit 7 based on the pulse signal a obtained from the detector 6.

The transport mechanism position/speed detection device of this embodiment is configured as described above, and the transport mechanism 1 is driven by the wheel drive motor 4 and moves on the rail 3.

When the detector 6 moves on the slit plate 5 as the transport mechanism 1 moves, a pulse signal a is output from the light receiving element of the detector 6 corresponding to each slit position.

Now, the number of output pulses is n (pieces), and the slit interval is Q (
+m), then the position IE b (m) from the origin is
b==nXQ It can be expressed as (1). On the other hand, if the time is monitored at this time and the position at time 9 to is b(to) and the position at time t1 (tx>to) is b(t 1), the speed c (m/5ec) is.

It can be expressed as

Therefore, the calculator 7 receives the pulse signal a obtained from the detector 6.
is counted, and based on the count value, the calculation of the above equation (1) is executed to calculate the current position of the transport mechanism l, and output it as a position signal. At the same time, the current speed of the transport mechanism I is calculated and outputted as a speed signal C by managing the time using an internal clock and executing the calculation of equation (2) above.

In this way, the slit plate 5 is fixedly provided in parallel with the rail 3, and at the same time, a detector 6 for detecting the slit of the slit plate 5 is provided in the moving side transport mechanism 1, and the moving side detection with respect to the fixed side slit plate 5 is provided. By detecting the position and speed of the device 6, position detection error factors such as play in the detection gear and slippage between the rail 3 and the axle zrIiJ, which have been problems in the past, are eliminated. As a result, highly accurate position and speed detection without measurement errors can be realized.

By the way, in the above embodiment, slit grooves are carved at regular intervals on the slit plate 5, pulses corresponding to the slit grooves are extracted from the detector 6, and the current position of the transport mechanism 1 is calculated by counting the pulses. I configured it like this, but
As shown in Fig. 5, the slit grooves provided on the slit plate 5 are coded as BCD code or Gray code, and as shown in Fig. 6, the coded slit positions are displayed on the detector 6. By correspondingly providing a light emitting element and a light receiving element, it becomes possible to detect the absolute position of the transport mechanism 1 without providing an origin slit or a counter.
, -Here, the slit groove shown in FIG. 5 shows an example of a 4-bit BCD code, and each slit has a weighting, slit 53 has a weighting of 2@, slit 54 has a weighting of 21. Surin, To 55 is 22, Slit 56 is 2
1, also represents the 61st ii! 1 shows an example of a detector for reading the BCD code, in which 26 light receiving elements 66, 2 light receiving elements 67, 22 light receiving elements 68, 21 light receiving elements 69 are arranged facing the light emitting element 65. has been done.

By combining the slit plate 5 shown in FIG. 5 and the detector 6 shown in FIG. 6, the moving position of the transport mechanism 1 can be detected in absolute position.

In the above-mentioned narrow example, a slit groove is cut in the slit plate 5, a light emitting element and a light receiving element are arranged with the slit plate 5 in between, and position detection is performed using transmitted light. Instead, slit marks with different reflectances may be attached, the light emitting element and the light receiving element may be placed on the same side, and the position may be detected using reflected light.

[Effects of the Invention] As described above, according to the present invention, position error factors such as play in the detection gear and slippage between the axle and the rail, which have been problems in the past, are eliminated, and high-precision position and speed detection of the transport mechanism is achieved. It becomes possible.

[Brief explanation of drawings]

FIG. 1 is a mechanical diagram of a position/speed detection device for a transport mechanism according to an embodiment of the present invention, FIG. 2 is a partially enlarged view of the slit plate in FIG. 1, and FIG. 3 is a slit detection section in FIG. 1. 4 is a block diagram of the position/velocity detection section of FIG. 1, and FIG. 5 is a partially enlarged view of a slit plate according to another embodiment of the present invention.
FIG. 6 is a configuration diagram of the slit detection section. 1...Transportation mechanism, 2...Wheels, 3...Rails,
4... Axle drive motor, 5... Slit plate, 6...
...Detector, 7...Arithmetic unit. Agent Patent Attorney Crest 1) Makoto Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] A device for detecting the position and speed of a transport mechanism moving on a rail via wheels, which comprises a slit plate fixedly arranged parallel to the rail, and a light emitting element and a light receiving element for detecting the slit of the slit plate. A position/speed detection device for a transport mechanism, characterized in that a detector is attached to the transport mechanism, and a signal from the detector is processed by a computing unit to output position detection information and speed detection information of the transport mechanism.