JP2000351409A - Conveyance device provided with turning mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use an inexpensive motor and control influence of noise on stopping accuracy by attaining the stopping accuracy of a turning device by means of the mechanical structure of the turning device itself. SOLUTION: A follower board 26 connected to a turntable is provided with a pair of notches 34, 35 and an oblong hole 36. A cam 24 is provided with rings 32, 33 which come in contact with the notches 34, 35 and pins 30, 31 which go into the oblong hole 36. When the cam 24 is rotated by 180 deg., a pin goes into the oblong hole 36 and comes out of it, while a ring and a notch contact with each other guiding the follower board 26 so that it turns by 90 deg.. By this, it is possible to turn a turntable forward and backward by a prescribed angle accurately with an inexpensive motor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for transporting articles.
In particular, the present invention relates to a transfer device provided with a turning mechanism for turning an article mounted on the transfer device by a mechanical mechanism by a predetermined fixed angle.

[0002]

2. Description of the Related Art In many cases, conveying devices such as tracked vehicles, unmanned transport vehicles, overhead traveling vehicles, and chain conveyors are provided with a turning device for changing the direction of articles. For example, a stepping motor or a servomotor is used to turn the turning shaft of these turning devices, and the turning angle of the turning shaft is read by an encoder or the like to control the turning angle of the motor. However, stepping motors and servo motors are generally expensive motors, and the control by the encoder is susceptible to electromagnetic noise, and the turning angle of the turning shaft is deviated by the noise. Had become crazy due to the influence of.

[0003]

A basic object of the present invention is to make it possible to use an inexpensive motor by achieving the stopping accuracy of the turning device by a mechanical mechanism of the turning device itself, and to make the stopping accuracy less affected by noise. It is intended to be hard to receive (claims 1 to 3). An additional object of the present invention is to further simplify the control of the motor. An additional object of the third aspect of the present invention is to provide a specific mechanism capable of rotating the turning device forward and backward by a fixed angle.

[0004]

According to the present invention, there is provided a transfer device provided with a turning mechanism for turning a mounted article, wherein the turning mechanism comprises a motor driven cam, a driven plate driven by the cam,
The cam and the driven plate are engaged only within a predetermined stroke range during rotation of the cam.

[0005] Preferably, a switch is provided which operates when the cam rotates by a predetermined angle wider than the stroke, and the motor is stopped by operating the switch.

Preferably, the engaging means includes a pair of projections provided on the cam, a single elongated hole provided on the driven plate for guiding the projections, and a driven plate of the driven plate engaged with the cam. It is composed of a pair of notches provided on both sides of the long hole, so that the driven plate does not rotate following the engagement of the cam and the notch alone.

[0007]

According to the present invention, the cam is rotated by the motor, the cam and the driven plate are engaged only within a predetermined stroke, and the driven plate is rotated. As a result, the rotation angle of the driven plate is determined by the stroke engaged by the engagement means, and has no relation to the stopping accuracy of the motor. Therefore, the driven plate can be accurately rotated by a predetermined angle using an inexpensive motor and a mechanical mechanism. Further, the rotation angle does not change due to electromagnetic noise.

According to a second aspect of the present invention, a switch for detecting the rotation of the cam is provided, and when the cam rotates by a predetermined angle wider than the stroke, the switch is operated to stop the motor. . Therefore, the control of the motor is further simplified, and the driven plate is rotated by a predetermined range during this period, so that the driven plate can be surely rotated by a predetermined angle.

According to the third aspect of the present invention, the pair of projections provided on the cam are guided by the elongated holes provided in the driven plate, and the driven plate is provided with cutouts on both sides of the elongated hole. , The driven plate is prevented from being driven and rotated, so that the projection enters the elongated hole and the driven plate rotates only during the escape. During this rotation, the projection of the cam advances and retreats along the longitudinal direction of the long hole, so when the projection enters or escapes from the long hole, no force is applied to the driven plate from the projection, and the driven plate is It turns exactly by a predetermined angle. In addition, by rotating the cam forward and backward by 180 degrees, the driven plate can be rotated by a predetermined angle even if only one long hole is provided in the driven plate. Further, since only one long hole is provided in the driven plate, even if the motor continues to rotate without stopping, the protrusion of the cam does not enter the long hole and the driven plate does not continue to rotate. Absent.

[0010]

1 to 6 show an embodiment. FIG. 1 shows an automatic warehouse system 2 using a tracked truck 7, 3 and 4 are a pair of racks, 5 is a stacker crane, 6 is a transfer device, and 7 is the tracked truck. 8 is the turntable. The tracked vehicle 7 is for loading and unloading articles with an overhead traveling vehicle or an unmanned carrier (not shown). And if the article has direction, for example, 9
The direction is changed between a direction suitable for storing the articles in the automatic warehouse system 2 by turning the turntable 8 by 0 degrees and a direction suitable for mounting on an automatic guided vehicle or an overhead traveling vehicle. Let it. Reference numeral 9 denotes a tracked truck similar to the above, but the turntable 8 is not provided because the direction of the article changes by 90 degrees while traveling in an L-shape. The transfer device provided with the turning mechanism of the present invention, in addition to tracked trucks, overhead traveling vehicles and unmanned transport vehicles,
What is necessary is just to use it for a chain conveyor, the transfer apparatus 6, etc.

FIG. 2 shows a main part of the tracked truck 7. 10 is a chassis of the tracked bogie 7; 12 is, for example, running wheels provided at four locations, which run along a guide rail 14; 16 is an elevating mechanism for elevating the turntable 8; Driven by the belt 20, the turntable 8 is moved up and down by a ball screw mechanism or the like (not shown). The elevating mechanism 16 is provided rotatably with respect to the chassis 10, and the cam 24 is rotated by the turning motor 22, whereby the driven plate 26 connected to the elevating mechanism 16 is rotated, for example, 90 degrees, and the turntable is turned. 8 is rotated.

FIG. 3 shows the turning mechanism of the embodiment.
Is the cam connected to the turning motor 22, 26 is the driven plate, and the cam 24 is provided with a pair of levers 28 and 29 which are turned by 180 degrees.
31 are provided. The cam 2 is located between the levers 28 and 29.
Rings 32 and 33 are provided along the edge of the fourth.

The driven plate 26 has an elongated hole 36 at one place, and the pins 30 and 31 enter and exit here. 3
Reference numerals 4 and 35 denote a pair of cutouts provided on both sides of the elongated hole 36. The rings 32 and 33 are engaged with the cutouts to restrict the rotation of the driven plate 26. When the pins 30 and 31 move into and out of the elongated holes 36, the pins 30 and 31 and the elongated holes 36 cause the rotation of the driven plate 26 due to the engagement between the rings 32 and 33 and the notches 34 and 35. Driven plate 26
The force for rotating the driven plate 26 is stronger, so that the driven plate 26 rotates only while the pins 30, 31 and the elongated hole 36 are moving in and out. The position of the driven plate 26 in the height direction is almost the same as the rings 32 and 33 and the pins 30 and 31.
The main surface of the cam 24 is below the driven plate 26. 38,
Reference numeral 39 denotes a projection used for detecting the direction of the driven plate 26.
SW3 is a switch, and 40 is a control unit.

FIG. 4 shows the rotation of the driven plate 26 caused by the rotation of the cam 24. Assuming that the cam 24 operates from the lower state to the upper state in FIG.
It stops in a state where it is in contact with W1, and the projection 39 is in contact with the switch SW3. From this state, the swing motor 22
Is started and the cam 24 is rotated counterclockwise, the pin 31 enters the elongated hole 36, and the driven plate 26 is rotated by, for example, 90 degrees by the pin 31. When the pin 31 escapes from the elongated hole 36, the cam 24 continues to rotate, but the driven plate 26 stops, and the protrusion 38 switches the switch SW to stop the rotation of the driven plate 26.
Detected from contact with 2. In the cam 24, the pin 3
When 0 contacts the switch SW1, the turning motor 22 stops and stops.

FIG. 5 shows the locus of the pin 31.
Enters the long hole 36 in the radial direction and escapes in the radial direction as shown by the chain line. For this reason, when the pins 30 and 31 move in and out of the long holes, no force acts between the pins and the long holes, and when the pins 30 and 31 escape from the long holes 36, the driven plate 26 immediately stops, and for example, Stopping accuracy of about ± 0.01 degrees can be obtained. In the embodiment, while the driven plate 26 is rotated by 90 degrees while the cam 24 is rotated by 180 degrees, the rotation angle of the driven plate 26 is, for example, 30 to 180 degrees, or 3 degrees.
It may be freely selected between 0 degrees and 120 degrees. Further, in the embodiment, the long hole 36 is provided only at one place, and the notches 34 and 35 are provided on both sides thereof, so that the rotation at a fixed angle can be performed in both the forward and reverse directions. Even if the cam 24 rotates too much due to a failure of the rotation motor 22 or the like, the pin 3
Since 0 and 31 do not hit the long hole 36 but the circumferential surface of the driven plate 26, the turntable 8 does not needlessly rotate.

FIG. 6 shows the rotation of the cam 24, the change in the angle of the driven plate 26, and the angular velocity of the driven plate 26. Cam 24
, The direction of the follower plate 26 changes smoothly at both ends of the movement and changes almost linearly at the middle, and the angular velocity becomes almost zero at the portion where the pins 30 and 31 enter and exit the slot 36 as described above. It is. Therefore, the pins 30 and 31 are
At the moment of entering, power is not working and pins 30, 3
As soon as 1 escapes from the elongated hole 36, the driven plate 26 stops.

[Brief description of the drawings]

FIG. 1 is a plan view of an automatic warehouse using a tracked truck according to an embodiment.

FIG. 2 is a side view of the tracked bogie according to the embodiment with a partially cutaway portion.

FIG. 3 is a view showing a turning mechanism of the tracked truck according to the embodiment;

FIG. 4 is a diagram showing a turning procedure in the embodiment.

FIG. 5 is a diagram showing a trajectory of a lever and a cam during turning in the embodiment.

FIG. 6 is a diagram showing an angle and an angular velocity of a driven plate during turning in the embodiment.

[Explanation of symbols]

 2 Automatic warehouse system 3,4 Rack 5 Stacker crane 6 Transfer device 7 Tracked truck 8 Turntable 10 Undercarriage 12 Running wheel 14 Rail 16 Elevating mechanism 18 Elevating motor 20 Belt 22 Swing motor 24 Cam 26 Follower plate 28,29 Lever 30 , 31 pins 32, 33 rings 34, 35 cutouts 36 elongated holes 38, 39 protrusions SW1 to SW3 switch 40 control unit

Claims (3)

[Claims] 1. A transport device provided with a turning mechanism for turning a mounted article, the turning mechanism comprising a motor-driven cam, a driven plate driven by the cam, a predetermined plate during rotation of the cam. A transfer device provided with a turning mechanism, comprising an engagement means for engaging a cam and a driven plate only within a range of a stroke. 2. A motor according to claim 1, wherein a switch is provided which is activated when said cam is rotated by a predetermined angle wider than said stroke, and said motor is stopped by operating said switch. A transfer device equipped with a turning mechanism. 3. A pair of projections provided on a cam, a single elongated hole provided on a driven plate for guiding the projections, and
It is composed of a pair of notches provided on both sides of a long hole of the driven plate so as to engage with the cam, and the driven plate does not rotate following the engagement of the cam with the notch alone. A transfer device provided with the turning mechanism according to claim 1.