Apparatus for switching over running directions of running member

Abstract

 An apparatus for switching over running directions of a running member (4,5) comprising a plurality of pair of rails (1, 2, 3, 36, 37) each having a running surface (S) and a groove (G) formed in the running surface, the running surfaces intersecting with each other in the same plane, a plurality of running wheels (6, 7) each of which is rotatably mounted on the running member, the running wheel having a tread surface (10) which comes into contact with the running surface of the rail and a flange (11) provided on the tread surface for engaging with the groove of the rail, turntables (13) each provided for the associated running wheel on an intersection of the rails, the turntable including a rotary disc (14, 44), a top surface of which is disposed within the same plane and is provided with a plurality of diametrical grooves 116,17, 38 to 43) circumferentially and equiangularly spaced from each other, and wheel turning mechanism (18, 27) provided on the running member for turning all of the running wheels about the respective rotary axes with the flanges of the running wheels being engaged with the radial grooves of the turntables.

Description

FIELD OF THE INVENTION AND RELATED ART STATEMENT

[0001] The present invention relates to an apparatus for switching over running directions of a running member, and more particularly to a running direction switching-over apparatus which is used at a rail intersection defined by two rails each having running surface so that a running member may run from one pair of rails to another pair of rails, running surfaces of which intersect with each other in the same plane.

[0002] A turntable type apparatus has been widely used in, for example, a parking area for automotive vehicles and an operating terminal for railway cars as the above-described running direction switching-over apparatus. In the conventional turntable type running direction switching-over apparatus, a turntable on which a running member is laid is turned so that the overall running member is turned, thereby switching over the running direction thereof. Thus, the running member may run on and along another running passage.

[0003] However, in such a running direction switching-over apparatus, since the running member as a whole is turned, there are many disadvantages. For instance, in case of an elongate running member, a wide space is required in particular to turn the running member. Also, there are some cases where the running member should be moved in a different direction without changing an orientation of the overall running member for loading/unloading works within a small site such as a warehouse. Furthermore, when a desired running member should be branched into a different direction from series running members in a row, that is, for example, in the case where inferior goods should be picked up from a flow of goods on an inspection line and be transferred onto another line with using the conventional turntable type running direction switching-over apparatus, an extra work is required to sufficiently separate a running member to be picked up from the adjacent running members for keeping a wide space for turning of the running member to be picked up. Moreover, in the case where it is impossible to take a sufficient space for the turn of the overall running member, the conventional turntable type switching-over apparatus is not applicable thereto at all.

OBJECT AND SUMMARY OF.THE INVENTION

[0004] Accordingly, an object of the present invention is to provide a running direction switching-over apparatus capable of changing running directions of a running member without changing an orientation of the running member.

[0005] According to the present invention, to attain this object, a rotatable turntable having diametrical grooves for guiding a running wheel of the running member is provided at each rail intersection. A wheel turning apparatus is provided in the running member for turning all the running wheels thereof about the respective axes of the turntables at the diametrical intersections.

[0006] Namely, when the running member moves to the rail intersections with the running wheels being located on the respective turntables at each rail intersections while the flange of each runningel is being guided by diametrical groove of the turntable, the running wheel is rotated about the axis of the turntable by wheel turning means provided in the running member to change the orientation of the running wheel. At this time, rotary discs of the turntables are also turned by the running wheels through the engagement between the flanges of the running wheels and the diametrical grooves of the turntables. When the orientation of a desired pair of rails is aligned with that of the running wheels, the running member may run in such a manner that the running direction of the running member is changed without changing the orientation of the overall running member.

[0007] With such a construction, the running direction of the running member may be changed without changing the orientation of the overall running member.

[0008] The features and meritorious advantages of the invention will become more apparent by the following description of preferred embodiments in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] 

Fig. 1 is an enlarged fragmentary sectional view showing an engagement between a turntable and a running wheel;

Fig. 2 is a plan view showing rail intersections;

Fig. 3 is a cross-sectional view taken along the line III-III of Fig. 2;

Fig. 4 and 6 are bottom views showing states of wheel turning means before and after the change in running direction of the running wheels;

Fig. 5 is an enlarged plan view showing the rail intersection;

Fig. 7 is a partially fragmentary plan view of the rail intersection shown in Fig. 5;

Fig. 8 is a bottom view showing another wheel turning means;

Fig. 9 is a plan view showing another rail intersection;

Fig. 10 is a plan view showing still another rail intersection;

Fig. 11 is a plan view showing a turntable shown in Fig. 10.

Figs. 12 and 13 are bottom views showing states of still another wheel turning means before and after the change in running direction of the running wheels.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] As shown in Figs. 2 and 3, running members, that is, carts 4 and 5 are mounted on two rail pairs 1 and 2 of three rail pairs 1, 2 and 3 arranged on a floor F. A running surface S of each rail of each rail pair is flush with a floor face. A groove G extends in a longitudinal direction in the running surfaces for guiding a flange of each running wheel (later described). Each cart 4, 5 may run freely on and along the rail pairs 1 and 2.

[0011] As shown in Figs. 1 and 4, at the bottom of the cart 4, four running wheels 6 and 7 are provided at intervals equal to distances A and B (see Fig. 2) between rails of the rail pairs. The running wheels 6 arranged on one of the diagonals are drive wheels which, as shown in Fig. 1, are rotated through speed reduction means by running motors 9 mounted on wheel mounting brackets 8. The running wheels 7 arranged on the other diagonal are driven wheels which are rotated by the running movement of the cart 4 caused by the drive wheels 6. As shown in Fig. 1 (which shows a detail of one drive running wheel 6), a flange 11 for being guided by the groove G formed in the running surface S of the rail is provided on an outer tread surface 10 of the running wheel 6, which is contacted with the rail running surface S of the rail. This makes it possible to prevent the cart from being displaced or offset in a transverse direction and to insure a stable running of the cart. The wheel mounting bracket 8 is mounted through bearings 12 to the bottom portion of the cart 4 so as to rotatable around its own vertical rotary axis.

[0012] Explanation as to the running direction switching operation for the carts 4, 5 will be made hereinafter.

[0013] First of all, for example, when it is required to switch over the cart 4 from the rail pair 1 to the rail pair 3, the cart 4 is moved to the intersections between the rail pair 1 and the rail pair 3, where the respective running wheels 6 and 7 of the cart 4 are mounted on the turntables 13 provided at the intersections of rails of the rail pairs 1 and 3. Rotary discs 14 of turntables 13 are embedded through bearings 15 in the floor F so as to be rotatable (Fig. 1). At least parts of top surface of the rotary disc 14, which is to be contacted with the outer tread surfaces 10 of the wheels 6 and 7, are flush with the running surfaces S of the rails. As best shown in Figs. 2 and 5, the rotary disc 14 is provided with diametrical grooves 16 and 17 intersecting with each other at a right angle. These diametrical grooves have the same cross sectional shape of the groove G of the rail and guide the flanges 11 of the running wheels. The flanges 11 of the respective running wheels 6 and 7 of the cart 4 which has run along the rail pair 1 are guided into the grooves 17 of the turntables 13 and the running wheels 6 and 7 are located on the turntables 13.

[0014] Although, in the foregoing embodiment, a depth of the grooves 16 and 17 of the rotary discs 14 is equal to that of the grooves G of the rails, it is possible to modify the depth of the grooves 16 and 17 so that the wheels 6 and 7 may be rotated with the outer surfaces of the flanges 11 thereof being in contact with the bottoms of the radial grooves 16 and 17. In this case, the top surface of the rotary disc 14 should be some what lowered in level than the running surface S of the rail so as to be out of contact with the outer tread surfaces 10 of the wheels when the cart 4 passes through the rotary discs. This makes it possible to prevent the wheels from rocking when the cart passes through the intersections where the running surface is interrupted.

[0015] Subsequently, the direction of the running wheels 6 and 7 of the cart 4 is changed from one state shown in Fig. 4 by wheel turning means 18 to another state shown in Fig. 6. In this case, the rotary disc 14 is also turned around the axis thereof since the flange 11 of the running wheel engages with the groove 17. In this embodiment, as shown in Fig. 7, positioning means 19 is provided in order to position the rotary discs 14 after being turned and to more insure the alignment between the radial grooves 16 and 17 of the rotary disc 14 and the grooves G in the rail running surfaces. The positioning means 19 includes a roller 21 biased by a spring 20 embedded in the floor and recesses 22 formed in an outer peripheral surface of the disc 14 for engagement with the roller 21 in alignment with the predetermined rotation position.

[0016] The wheel turning means 18 is a link mechanism which comprises a rod 24 provided at intermediate portion thereof with a rack 25 and at opposite ends thereof with arms 23 fixed to the wheel mounting brackets 8 of the respective running wheels 6 and 7, a pinion (not shown) in engaging with the rack 25 and a direction switching motor 26 for driving the pinion. The wheel turning means 18 causes the running wheels 6 and 7 to turn about the rotary axes of the turntables to change the running direction. The wheel turning means 18, however, is not limited to the one shown in Figs. 4 and 6. A worm and threaded shaft unit may be used instead of the rack and pinion link mechanism. Also, a mechanism 27 shown in Fig. 8 may be applicable to the wheel turning means. The wheel turning means 27 shown in Fig. 8 is composed of sprockets (located in the rear sides of the running wheels 6 and 7 in Fig. 8) fixed to the respective brackets 8, an endless chain belt 28 engaged with the sprockets, and a motor 30 for driving the chain belt 28 through another sprocket 29.

[0017] Furthermore, a link mecahnism 45 shown in Fig. 12 is applicable as the wheel turning means. The lin" mechanism 45 comprises a rod 46 provided at intermediate portion thereof with a rack 47 and at opposite ends thereof with arms 48 fixed to the wheel mounting brackets 8 of the running wheels 6 and 7, a pinion (not shown) in engaging with the rack 47, and a pair of link rods 49 each connecting the brackets 8 of the running wheels 6 and 7. The link rod 49 is provided at opposite ends thereof with arms 50 fixed to the brackets 8. A direction switching motor 51 is provided to be associated with the link mechanism 45 to drive the pinion thereof. The link mechanism 45 can cause all of running wheels 6 and 7 to turn simultaneously about the rotary axes of the turntables to change the running directions of the running wheels (Fig. 13).

[0018] The direction of the running wheels may be changed as desired, under the control of the suitable wheel turning means 18 or 27. Accordingly, such wheel turning means may be applied not only to the case where the rails are intersecting with each other at right angles, as shown in Fig. 2, but also the case where the rails are intersecting obliquely with each other as shown in Fig. 9. In the latter case, three diametrical grooves 32, 33 and 34 are formed in the rotary disc 14 at an angular interval of 120° if the intersection angle of the rails is at 60° as shown in Fig. 9, for example.

[0019] Furthermore, in the case where, as shown in Fig. 10, two pairs of rails 36, 37 intersect with another pair of rails 35 at angles 90° and 60°, it is sufficient to provides diametrical grooves 38, 39, 40, 41, 42 and 43 (see Fig. ll) in the rotary disc 44 at an angle of 30° which is the greatest common measure or divisor of 360°, 90° and 60°.

[0020] As has been apparent from the foregoing description, according to the running direction switching-over apparatus of the invention, it is possible to change the running directions of the running member such as a cart without changing the overall running member's orientation.

[0021] Also, according to the present invention, since the turntables associated to the respective wheels are provided at the respective intersections of the rails, small size turntables suffice. Since the turntables are rotated through the wheels by the wheel turning means provided in the running member, it is unnecessary to provide a driving mechanism to each turntable and a simple structure in which each turntable is rotatable in the floor may suffice. Furthermore, since the turn of the turntable is attained by the engagement between the wheel flange and the diametrical groove of the rotary disc, it is unnecessary to provide a complicated turning mechanism.

[0022] Also, in the case where the running direction switching-over apparatus according to the present invention is applied to the running member running on and along the rails formed in the floor, there is no projection from the floor. Thus, other vehicles or working men are not obstracted in movement.

[0023] Moreover, according to the present invention, since a plurality of the diametrical grooves in the rotary discs of the turntable are formed equiangularly, even after the running member has changed its running direction and passed through the intersection and then the turntable is turned, any one of the plurality of diametrical grooves is always in alignment with one rail groove. Therefore, it is unnecessary to return the turntable back to the original position and the running members may run in any desired direction one by one in a continuous manner.

Claims

1. In an apparatus for switching over running directions of a running member comprising a plurality of pairs of rails each having a running surface and a groove formed on said running surface, the running surfaces intersecting with each other in the same plane, and a plurality of running wheels each of which is rotatably mounted on said running member, the running wheel having a tread surface which comes into contact with said running surface of the rail and a flange provided on said tread surface for engaging with said groove of the rail, the improvement comprising:

turntable means each provided for the associated running wheel on an intersection of the rails, said turntable means including a rotary disc, a top surface of which is disposed within said same plane and is provided with a plurality of diametrical grooves circumferentially and equiangularly spaced from each other, which diametrical grooves are able to engage with said flange of the running wheel; and

wheel turning means provided on said running member for turning all of said running wheels about their respective rotary axes with the flanges of the running wheels being engaged with said diametrical grooves of said turntable means.

2. An apparatus according to Claim 1, wherein said turntable means includes a journal member affixed to a bottom surface of said rotary disc, and bearing means for bearing said journal member rotatably.

3. An apparatus according to Claim 1, wherein said wheel turning means includes:

at least one link mechanism for connecting a pair of associated running wheels; and

driving means for driving said link mechanism.

4. An apparatus according to Claim 3, wherein one of said associated running wheels is passively rotatable, and the other running wheel is provided with driving means for driving said the other running wheel.

5. An apparatus according to Claim 1, wherein said wheel turning means includes:

an endless belt engaging all of said running wheels; and

driving means for driving said endless belt.

6. An apparatus according to Claim 5, wherein at least one of said running wheels is provided with driving means for driving the running wheel.

7. An apparatus according to Claim 1, wherein said plurality of pairs of rails intersect with each other at a right angle.

8. An apparatus according to Claim 1, wherein said plurality of pairs of rails intersect obliquely with each other.

9. An apparatus according to Claim 1, wherein said wheel turning means includes:

link mechanism for connecting associated running wheels; and

driving means for driving said link mechanism.

10. An apparatus according to Claim 9, wherein some of said associated running wheels are passively rotatable, and the rest of running wheels are provided with driving means each for driving the respective running wheels of said rest of runnig wheels.

Drawing