JPH0539040A - Turn table rotary driving device - Google Patents

Abstract

PURPOSE:To provide a turn table rotary driving device which is easy to manufacture at a low cost and has a large driving force and good operation performance. CONSTITUTION:A turn table 15 fixed with connecting rails 16 on the upper face is provided rotatably at the intersection between rails 12, 13 crossing together. A screw shaft 26 rotated by a driving motor 29 is provided below the turn table 15, and a linear shift base 27 moved by its rotation is supported on the screw shaft 26. A cam follower 28 is provided on the linear shift base 27, and a guide 30 coupled with it is fixed on the lower face of the turn table 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turntable rotation drive device used for driving a turntable which is loaded with a heavy load such as a vehicle and rotates.

[0002]

2. Description of the Related Art Conventionally, as a rotary drive device for a turntable, which is used for changing the direction at the entrance and exit of a parking lot or for sorting the cargo at a cargo collection / delivery site, the one shown in FIG. 6 is known. There is.

In FIG. 1, a turntable 1 is horizontally rotatably installed on a fixed base 2, and is forcibly rotated by a rotary drive device composed of a large gear 3, a small gear 4 and a drive motor 5. It has become so. The large gear 3 is provided integrally with the turntable 1 coaxially with the rotation shaft of the turntable 1, and the small gear 4 is provided at one end of the large gear.
Are engaged with each other, and the turntable 1 is forcibly rotated by rotating the small gear 4 by a drive motor 5 via a transmission means such as a chain.

[0004]

In the above-mentioned conventional rotary drive device, the large gear is provided coaxially with the turntable and integrally with the turntable. There is a problem that the technique becomes expensive because it requires a processing technique and a long processing time.

In view of such conventional problems, an object of the present invention is to provide an inexpensive turntable rotary drive device which can obtain a large driving force without using an expensive large gear and can obtain an efficient operation. It was done.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned conventional problems and to achieve the intended purpose, the gist of the present invention is to allow the central portion to rotate in the horizontal direction. On a fixed base under the installed turntable, a screw shaft installed in a direction intersecting with the turning radius direction of the turntable, a linear moving base screwed to the screw shaft, and rotationally driving the screw shaft. A linear movement means composed of a drive motor is provided, a cam follower is supported upward on a moving base of the linear movement means, and the cam follower is slid on the lower surface of the turntable in the radial direction of rotation thereof. The present invention resides in a turntable rotation drive device including a guide that is freely fitted.

[0007]

In the present invention, the drive motor rotationally drives the screw shaft, and the linear moving base screwed onto the screw shaft linearly moves on the screw shaft in proportion to the rotation speed of the screw shaft. ..

The cam follower supported upward by the linear moving base moves linearly with the linear moving base to push the linear moving base in the linear moving direction while sliding in the guide. This causes the turntable to rotate in the same direction.

Further, when the linear moving base moves from one end to the other end on the screw shaft, it comes closest to the center of rotation of the turntable at its central portion, so that the linear moving base moves from one end of the screw shaft. The rotation speed of the turntable increases toward the central portion, and decreases as it approaches the other end, that is, the end end from the central portion. That is, the rotation speed of the turntable increases from the rotation start end to the rotation center position, and decreases as it approaches the rotation end.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention implemented as a direction changing device for a truck traveling on a rail will be described with reference to FIGS.

Rails 12 and 13 oriented orthogonally to each other are laid on the floor surface 11, and a turntable storage hole 14 is provided at an intersecting portion of the rails 12 and 13, and the turntable storage hole 14 is provided in the turntable storage hole 14. A turntable 15 is housed at the same height as the floor 11. A connecting rail 16 is provided on the turntable 15, and when the turntable 15 is rotated by 90 °, the connecting rail 16 becomes a track continuous to one rail 12 and a track continuous to the other rail 13. To be selected.

A bearing device 18 is provided at the center of the fixed base 17 at the bottom of the turntable storage hole 14.
A rotation center shaft 19 protruding from the lower surface of the center of the turntable 15 is rotatably supported.

The bearing device 18 is composed of an upward opening type housing 20 fixed to a fixed base 17, and a radial bearing 21 and a thrust bearing 22 housed in the housing 20. Supports in both directions.

A turntable support rail 23 is laid on the fixed base 17 in a circular arrangement centered on the rotation center shaft 19, and turntable support wheels 24 mounted on the lower surface of the turntable 15 roll on the turntable support rail 23. It is like this.

A turntable driving device 25 is provided below the turntable 15 rotatably housed in the storage hole 14 in this manner.

As shown in FIGS. 2 and 3, the device 25 comprises a screw shaft 26, a linear moving base 27, a cam follower 28, a drive motor 29, and a guide 30.

The screw shaft 26 is provided with a ball screw groove having a substantially semicircular cross section on its outer periphery excluding both ends, and both ends are provided on a supporting frame 31 on the fixed base 17 so as to project from the pair of bearings 3.
2 and 32 are rotatably supported so as to be immovable in the axial direction, one end of the screw shaft 26 is projected from the bearing 32, and a sprocket 33 is attached to the tip end of the fixed base 17. The rotation of the drive motor 29 installed above is transmitted.

The linear moving base 27 is composed of two nuts 34, 34 screwed to the screw shaft 26 and a moving base plate 35 to which the nuts are fixed. The moving base plate 35 has a contact portion on its upper surface. A cam follower 28 composed of a rotating roller is supported upward.

Further, a pair of movable table guide plates 37, which are parallel to and opposed to each other on both sides of the screw shaft 26, are erected on the support frame 31, and the nut 3 of the linear movable table 27 is provided.
4 is clamped from both sides to prevent the linear moving table 27 from rotating. As a result, when the screw shaft 26 is rotated, the linear moving base 27 is movable in the longitudinal direction of the screw shaft 26.

The guide 30 is composed of a pair of guide plates 39, 39 which are hung downwardly so as to face each other on the lower surface of a rectangular guide base plate 38, and the guide base plate 38 is placed on the lower surface of the turntable 15. It is fixed in the radial direction.

The cam follower 28 is slidably fitted between the guide plates 39, 39 of the guide 30.

Below the turntable 15, a turntable angle detecting device 40 is provided. This device is provided with a limit switch operating protrusion 41 provided on the lower surface of the turntable 15, a pair of emergency stop limit switches 42a and 42b arranged on the rotational movement line thereof, and a pair of stop limit switches 43a and 43b. And the speed limit switches 44a and 44b, and the stop limit switches 43a and 43b are provided at a distance of approximately 90 ° about the rotation center shaft 19 and are provided at both switches 43a and 4b.
3b close to the inside of the speed limit switch 44
a and 44b are outside the limit switch 42 for emergency stop
a and 42b are provided respectively.

Stop limit switches 43a, 43b
Operates the operation projection 41 to turn off the power of the motor 29, and the emergency stop limit switches 42a and 42b are operated even if the stop limit switches 43a and 43b malfunction. It is an emergency stop when the motor 29 is not stopped.

Further, the speed varying limit switch 44a,
Reference numeral 44b is for converting the frequency of the power source of the drive motor 29 into 50 Hz and 20 Hz.
Immediately after the start of rotation and before stopping rotation of No. 5, the rotation speed is switched to 20 Hz to slow down the rotation speed, and the rotation intermediate operation portion is set to 50 Hz to operate at high speed.

In the figure, reference numeral 45 denotes a turntable rotation lock mechanism, which includes a hydraulic cylinder 46 and a tapered taper locking piece 4 fixed to the tip of the rod of the hydraulic cylinder 46.
7 and a taper recess 48 into which the locking piece 47 provided on the turntable 15 is screwed. By pushing the locking piece 47 into the tapered recess 48, the stop angle of the turntable 15 is finely adjusted. It is locked so that it cannot rotate.

In the embodiment described above, the turntable 15
However, the turntable may be driven to rotate by 180 ° by using two sets of similar mechanisms.

In this case, as shown in FIG.
The two screw shafts 26a at positions symmetrical to each other about 9
26b is provided, and a pair of guide rails 3 are arranged at a right angle.
0a, 30b are fixed to the lower surface of the turntable 15, and when one guide 30a rotates 90 ° from the first position A and reaches the second position B, the cam follower 28a causes the guide 3a to move.
0a, and in this state, the cam follower 28b on the other end side is started so that the third position C
By engaging the guide 30b on the other end of the turntable 1 and rotating the guide 30b to the fourth position D, the turntable 1
5 is rotated an additional 90 °.

[0028]

As described above, according to the present invention, it is possible to drive the turntable by an inexpensive method without using a large-diameter expensive gear as in the prior art, and in the turning radius direction of the turntable. A guide is provided, and a screw shaft is provided in a direction that intersects with the rotation radius direction, and the turntable is rotated by the linear motion of the cam follower, so that the rotation speed is naturally gentle near the start and end points, It becomes a high speed at the middle point, and it is possible to reduce the impact at the time of starting and stopping even if a heavy object is loaded on the turntable.

[Brief description of drawings]

FIG. 1 is a partially cutaway plan view of an example of a turntable using the device of the present invention.

FIG. 2 is a partial vertical sectional view of the above.

FIG. 3 is a side view of the rotary drive portion of the above.

FIG. 4 is a front view of the above turntable angle detection device.

FIG. 5 is a plan view showing a schematic configuration of a second embodiment.

FIG. 6 is a partially cutaway plan view showing a conventional technique.

[Explanation of symbols]

 11 floor surface 12, 13 rail 14 turntable storage hole 15 turntable 16 connecting rail 17 fixed base 18 bearing device 19 center of rotation 20 housing 21 radial bearing 22 thrust bearing 23 turntable support rail 24 turntable support wheel 25 turntable drive Device 26 Screw shaft 27 Linear moving base 28, 28a, 28b Cam follower 29 Drive motor 30, 30a, 30b Guide 31 Support frame 32 Bearing 33 Sprocket 34 Nut 35 Moving base plate 37 Moving base guide plate 38 Guide base plate 39 Guide plate 40 Turntable angle detector 41 Limit switch operation protrusions 42a, 42b Emergency stop limit switches 43a, 43b Stop limit switches 44a, 44b Speed variable limit Switch 45 turntable rotation lock mechanism 46 hydraulic cylinder 47 the locking pieces 48 tapered recess

Claims (1)

[Claims] 1. A fixed base under a turntable that is rotatably installed in a horizontal direction with a central portion as a center of rotation,
A linear movement means comprising a screw shaft installed in a direction intersecting with the turning radius direction of the turntable, a linear moving base screwed to the screw shaft, and a drive motor for rotationally driving the screw shaft, A turn comprising a cam follower supported upward on a moving base of the linear movement means, fixed to the lower surface of the turntable in the direction of the rotation radius thereof, and provided with a guide into which the cam follower is slidably fitted. Table rotation drive device.