CA1065189A - Vehicle and track system - Google Patents

Abstract

VEHICLE AND TRACK SYSTEM

Abstract of the Disclosure A track system is arranged to be flush with the floor and a drive shaft is mounted for rotation beneath the level of the floor. A vehicle mounted on wheels is moved along the tracks by a drive wheel which extends downwardly from the bottom of the vehicle through an elongated slot in the floor and which contacts the drive shaft. The vehicle includes a bumper system which upon impact oscillates the drive wheel into a posi-tion which decellerates and stops the vehicle. A cam associated with the drive wheel selectively cooperates with a cam surface located beneath the floor level at a queuing station for oscil-lating the drive wheel into a position which decellerates and stops the vehicle. Means are also provided at the queuing sta-tion for positively holding the vehicle in a stopped position.

Description

1 Background of the Invention This invention relates to a vehicle and track system of the type classified in Class 104. The types of systems involved herein are exemplified by U. S. Patent 3,356,040 and U. S. Patent 3,818,837.
While these prior art systems have been quite satis-factory for some installations, they do have several drawbacks.
One of the primary pro~lems is one of safety in that the rails upon which the vehicles ride, the drive motors, queue stations, and other system equipment are exposed. In such prior art in-stallations, there is a safety hazard if it is desired to provide for pedestrian or vehicle traffic in a direction transverse to the direction of the tracks. In addition, such prior systems were not be particularly aesthetically or architecturely pleasing.

Disclosure This invention is directed to a driverless vehicle and track system wherein the tracks or rails are arranged to be flush with a support surface such as the floor. The vehi~le drive shaft is mounted for rotation beneath the level of the floor and between the tracks. A vehicle mounted on wheels is moved along the tracks by a drive wheel. The drive wheel is supported by a shaft means which extends downwardly from the bottom of the vehicle through an elongated slot in the floor on the center line of the system. The periphery of the drive wheel contacts the periphery of the drive shaft to propel the vehicle. A cam as-sociated with the drive wheel cooperates with a ca~ surface located beneath the floor level at a queuing station for oscil-la~ing the drive wheel about an upri~ht axis into a position which decellerates and stops the vehicle. The vehicle ~ay 51t~'~

include a bumper system which upon impact also oscillates t;~e drive wheel into a pOSition which decelerates and stops the vehicle.
It is an object of the present invention ~o provide a nove] v~hicle and track system.
It is another object of the present invention to provide a novel vehicle and track system which is aesthetically and architecturally pleasing.
It is another object of the present invention to provide a novel vehicle and track system which is constructed in such a manner that it does not result in a safety hazard to persons in the operating area.
It is a still further object of the present invention to provide a novel vehicle and track system wherein all of the operating and control equipment for the system are located beneath the floor level.
In accordance with one broad aspect, the invention relates to apparatus comprising a vehicle having a portion for supporting a load, said vehicle being mounted on wheels adapted to ride on a track, a drive wheel means on the bottom side of said vehicles and extending downwardly therefrom, said drive wheel means including a drive wheel oscillatable about an upright axis between a drive position and a stop position, said drive wheel being rotatable about a horizontal axis, a control member coupled to said drive wheel for oscillating said drive wheel about said upright axis, said control member being mounted for oscillation between a vehicle drive position ~nd a vehicle stop position, said control member being movable in response to an actuator external of the vehicle, a stop element for lLmiting the extent to which said control member may oscillate, said stop member being on the bottom side of said ~' ~ 2 -~ .~

51~3~3 vehicle and rigidly connected thereto, each of said drive wheel and control member being entirely below the elevation of the lowermost part of said wheels upon which said vehicle is mounted.
Other objects will appear hereinafter.
For the purpose of illustrating the invention, there is shown in the drawings a form which ~s presently preferred;
it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown.
Figure 1 is a top plan view, partially broken away, of a vehicle and track system in accordance with the present invention.
Figure 2 is a sectional view taken along the line 2-2 in Figure 1.
Figure 3 is a sectional view taken along the line 3-3 in Figure 2.
Figure 4 is a sectional view, on an enlarged scale, '.
taken along the line 4-4 in Figure 3.

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~;\ -2A-~ 51 ~3 1 Figure 5 is a sectional view, on an enlarged scale, taken along the line 5-5 in Figure 3.
Referring to the drawings in detail, wherein like numerals indicate like elements, there is shown in Figures 1, 2 and 3 a vehicle and track system in accordance with the present invention. The vehicle is designated generally as 10 and is adapted to ride along tracks 12 and 14 of the system. In Figure 1, the vehicle 10 is driven in the direction of arrow 16 by means of drive shaft 18. Drive shaft 18 is rototably driven for rotation about its longitudinal axis by means of a reversible motor not shown. The drive shaft 18 is comprised of a plurality of axially aligned tubular sections supported for rotation by a plurality of suitable bearings such as shown at 20 and 22. The rotary movement of the drive shaft 18 is converted into longitu-dinal movement of the vehicle 10 by interaction of the dri~e shaft 18 with drive wheel 24 mounted on the vehicle.
In a manner to be more fully described hereinafter, drive wheel 24 is mounted for rotation about a horizontal axis.
When the axis of rotation of drive wheel 24 is parallel to the axis of drive shaft 18, there is no movement of the vehicle 10 in the direction of arrow 16. The drive wheel 24 is supported on the bottom side of the vehicle 10 by means of a shaft 26 and is spring ~iased to the position shown in Figures 1, 2 and 3 wherein the axis of rotation of the wheel 24 is at an acute angle of approximately 35-45 with respect to the longitudinal axis of drive shaft 18. In this position, the vehicle 10 is driven longitudinally in the direction of the arrow 16.
As shown best in Figure 3, the upper surfaces of tracks 12 and 14 are arranged to be flush with and actually form the continuation of a support surface or floor 28. Tracks 12 and 14 I ntj5~

1 are comprised of I-beams mounted on supports 30 and 32 respective-ly. Floor 28 is provided with a hollow channel 34 within which is mlounted supports 30, 32, the drive shaft 18, and various elements for controlling the operations of the vehicles 10 which will be described more fully here;nafter.
A continuous elongated slot 36 in the floor 28 substan-tially on the center line of the system between track 12 and 14 accommodates the shaft 26 extending do~-nwardly from the vehicle 10. Access to channel 34 is attained by removable plates 27 at spaced locations. Plates 27 are supported flush with floor 28 by brackets 29 on tracks 12, 14. The slot 36 may be lined on either side with a material such as shown at 38 and 40 for reducing wear caused by guide followers 64 and 66 rubbing against the sides of the slot 36 as the vehicle 10 is moved.
The vehicle is comprised essentially of a frame having side longitudinally extending support beams 42 and 44 and a central longitudinally extending support beam 46. A front laterally extending plate 48 joins the front ends of the support beams 42, 44 and 46 and similarly a rear laterally extending plate 50 joins the rear ends of the support beams. In addition, cross braces 52 and 54 extend between and are rigidly connected to the side support beams 42 and 44.
The vehicle 10 is provided with four wheels 56, 56', 58, 58' which are mounted to the outsides of side support beams 42 and 44 by suitable axles such as shown at 60 and 62. ~1heels 56, 56', 58 and 58` are adapted to ride on the upper surfaces of tracks 12 and 14. In order to guide the vehicle 10 and maintain the wheels on the tracks 12 and 14, the vehicle is provided with a pair of downwardly dependin~ guide followers 64 and 66. Guide follower 64 is mounted adjacent the front of the vehicle 10 1 substantially along the center line thereof and similarly guide follower 66 is mounted at the rear of thP vehicle adjacent the center line. Guide followers 64 and 66 extend into the slot 36 and have a diameter slightly smaller than the width of slot 36.
Followers 64, 66 rotate about a vertical axis and are adapted to guide the vehicle 10 as it is moved.
A plurality of conveyor rollers 68 are mounted on top of the vehicle frame for ease of loading and unloading. Rollers 68 have suitable axles 70 journaled into front beam 72 and rear beam 74. Front bea~ 72 and rear beam 74 are, in turn, rigidly secured to front and rear plates 48 and 50, respectively, of the vehicle frame through suitable bolts such as shown at 76 and 78.
As seen in Figure 3, the plurality of conveyor rollers 68 are arranged such that the rollers closest to the left side of the vehicle 10 (as viewed in Figure 3) are slightly lower-than the rollers to the right side. As a result, when a load such as a box 80 is placed on the vehicle, it rolls down the conveyor rollers 68 until it hits the stop 82 at the left side wall 84.
Fxont and back walls 86 and 88 help guide the box ~0 on the conveyor rollers and help maintain the box in position. Thus, it can be seen that even though the top carrying area of the vehicle 10 is open on three sides, the box 80 will not work itself off the vehicle 10 by vibration when the vehicle is in motion. This eliminates the need for roll breaks or other similar mechanisms.
With this construction, loading and unloading is preferably accomplished from the right side as shown in Figure 3. 1, A bumper system, carried by the vehicle 10, deceller-ates and stops the vehicle whenever it comes into contact with another vehicle or any other obstacle in its path. The bumper system includes a laterall~ e~tending bumper 90 positioned for-~ 5~ ~3 1 warclly of the vehicle. The bumper 90 is supported by longitu-dinally extending rods 92 and 94 which pass through suitable openings in the front plate 48, front slide bearings blocks 96 and rear slide bearing blocks 98. The bearing blocks 96 and 98 are secured to the front and rear support braces 52 and 54, respectively, through bolts such as shown at 100. A connecting plate 102 is securely fastened to rods 92 and 94 through bolts 104. Bumper 90 is biased outwardly toward the fo~ard direction of the vehicle 10 by a spring 106 connected between front support brace 52 and a bolt 108 secured to rod 92. Forward movement of bumper 90 is limited by a pair of L-shaped stop elements 110 and 112 secured to the connecting plate 102 and which are adapted to abut rPar support brace 54 when bumper 90 is in its forwardmost position. Resilient means such as at 114 and 116 are provided between stop members 110 and 112 and rear support brace 54. Rod 92 also carries a cam plate 118 having an elongated opening 120 therein which is formed at an angle with respect to the longi-tudinal axis of the vehicle.
As stated above, drive wheel 24 is carried by shaft 26 so that the wheel 24 can be oscillated about a vertical axis. It can be seen in Figures 2 and 3 that shaft 26 is rotatable secured to central support beam 46 through a bearing 122. Bolts 124 and 126 securely ~asten bearin~ 122 to the central support beam 46.
Shaft 26 extends above bearing 122. A two-side control lever 128 is rigidly fastened to the upper extension of the shaft 26 by a nut 130.
A cam follower 132 is rotatably mounted to one end of control lever 128 by bolt 134 and e~tends downwardly from lever 128 into slot 120 of cam plate 118. A spring 136 is connected between the other end of control lever 128 and the rear support 1 brace 54 so as to bias the control lever 128 for clockwise rotation as viewed in Figure 1. A suitable stop means in the forrn of a screw 138 prevents clockwise rotation of control lever 128 past the position shown in Figure 1 and a similar adjustable stop means in the form of a screw 140 limits the counterclockwise movement of control lever 128.
The bun~per system functions as follows. Since spring 136 biases control lever 128 and hence drive wheel 24 in the position shown in Figure 1, rotation of drive shaft 18 results in movement of the vehicle 10 in the direction shown by arrow 16.
Upon impact with another vehicle or some other obstacle in its course, bumper 90 moves rearwardly against the tension of spring 106 and carries with it cam plate 118. Cam follower 132 riding in slot 120-also moves rearwardly causes counterclockwise rota-tion of control lever 128 as viewed in Figure 1. Since control lever 128 is rigidly secured to shaft 26, counterclockwise move-ment of control lever 128 oscillates drive wheel 24 in the counterclockwise direction until the axis of drive wheel 24 is - parallel with the axis of drive shaft 18. Adjustable stop means 140 is adjusted so that control lever 128 cannot be rotated past the position where the axis of drive wheel 24 is parallel with the axis of drive shaft 18. In this position, rotation of drive shaft 18 does not impart movement to the vehicle 10 in the direction of arrow 16 and the vehicle stops.
The vehicle 1~ can also be stopped at desired ~ueuing ;~ stations strategically spaced throughout the system. At the queuing stations, the vehicles sre decellerated, stopped and . positively held in the stop position primarily by the cooperation . . .
of cams and ca~ followers to be described below.
The lower end of shafe 26 is provided with a yoke ~n~sl~?
1 member 142 having an upper section 144 and a ~air of spaced apart downward projections 146 and 148. Set screw 150 rigidly secures yoke member 142 to shaft 26 so that movement of one causes movennent of the other. Drive wheel 24 is rotatably mounted on an axle~ not shown, extending between downward projections 146 and 148 of yoke 142. Horizontally disposed plates 152 and 154 are rigidly secured to the bottom of projections 146 and 148 and extend outwardly away from drive wheel 24. An arcuately shaped cam plate 156 extends between plate 152 and 154 and is rigidly secured thereto through bolts 158 and 160. Similarly, an arc-uately shaped cam plate 162 extends between plate 154 and plate 152 and is rigidly secured thereto through bolts 164 and 166, re-spectively. A cam follower 168 is secured to cam plate 156 through a bolt 170 and depends downwardly therefrom. Similarly, cam follower 172 is secured to cam plate 162 by a bolt 174 and depends downwardly therefrom.
The vehicle 10 also includes a post 176 which is secured to the central beam 46 adjacent the longitudinal center thereof and slightly to the rear of bearing 122. Post 176 depends downwardly through slot 36 and carries a horizontally di~posed V-shaped plate having arms 178 and 180. Arms 178 and 180 extend toward the front of the vehicle 10 and terminate substantially at the center line thereof on either side of shaft 26. A cam follower 182 extends downwardly from the end of arm 178 and a cam follower 184 extends downwardly from the end of arm 180.
Each queuing station includes a cam element 186 with a straight cPntral cam surface 188 parallel to shaft 18 and out-wardly inclined surfaces 190 and 192 extending from the central surface 188 to provide for gradual smooth acceleration and de-~ 5~
1 celeration. The ends of cam element 186 are pivotally mounted to upright supports 1~4 and 196 through bolts 198 and 200 so that cam element 186 can be moved between its full upright position as shown in solid lines in Figure 3 and its full downward position as shown in phantom in Figure 3.
Cam element 186 is moved into its upright, operative position by an air cylinder 202 which is pivotally connected to a bracket 204. The piston rod 206 of air cylinder 202 is pivotally connected to the center of a forked lever 208 which has its bottom end pivoted to a bracket 210. A roller 212 is rotatably mounted at the upper end of forked lever 208 between the two forks thereof. When piston rod 206 of air cylinder 202 is retracted, forked lever 208 moves clockwise as viewed in Figure 3 thereby lowering cam element 186. Similarly, when the piston rod 206 of air cylinder 202 is extended, lever 208 rotates counter-clockwise as viewed in Figure 3 and forces cam element 186 upward-ly into its operative position.
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Mounted above cam element 186 at a level substantially even with cam followers 182 and 184 are a pair of cam elements J, 20 214 and 216. Cam elements 214 and 216 are horizontally arranged but are mounted to pivot about vertical axes through bolts 218 ; and 220 secured to frame 222. Frame 222 is mounted on a platform 224 which is securPd to upright supports 194 and 196. See Figure 5.
Cam elements 214 and 216 are biased into the operative .: .
position shown in Figure 4 by a spring 226 extending between ;~ posts 228 and 230 depending downwardly from cam elements 214 and :
i 216, respectively. Als~ dependin~ downwardly from cam elements ., i f ~ 214 and 216 are ca~ followers ~32 and 234. An air cylinder 236 mounted to platform 222 through brac~et 238 has its piston rod ~ - 9 -,:, 1 240 extending between cam followers 232 and 234. A cross bar 242 extends outwardly on either side of piston rod 240 snd engages cam followers 232 and 234.
I~hen piston rod 240 of air cylinder 236 is fully ex-tended, as shown in Figure 4, ca~ elements 214 and 216 are biased inwardly toward drive shaft 18 by spring 226 and are in their operative position. When piston rod 240 of air cylinder 236 is retracted, cross bar 242 moves outwardly away from drive shaft 18. Cam followers 232 and 234 follow cross bar 242 outwardly thereby pivoting cam elements 214 and 216 outwardly away from drive shaft 18 and against the tensi~n of spring 226.
The queuing station operates as follows. As a vehicle 10 approaches the queuing station, the cam surface of plate 156 or plate 162 engages and trips a limit switch, not shown, which through an appropriate hydraulic or compressed air system en-ergizes air cylinders 202 and 236 thereby extending their piston rods 206 and 240. It should be noted that since cam plates 156 and 162 are arcuately shaped, they provide the same surface conditions for the actuation of the limit switch regardless of the angular position of the shaft 26. This means that the limit switch will be actuated regardless of the speed at which the vehicle 10 is moving.
Actuation of air cylinder 202 moves cam elemen~ 186 upwardly into the operative position shown in Figure 5. Actua-tion of air cylinder-236 allows cam elements 214 and 216 to return to their operative position shown in Figure 4 as a result of the tension of spring 226. As vehicle 10 continues to ap-- proach the queuing station,. cam ~ollower 168 engages cam surface .~ 190 and causes sha~t 26.and hence drive wheel 24 to oscillate in ~ 30 a counterclockwise position as viewed in Figure 4. As discussed ~ 3 1 above, this results in a decelleration of the vehicle 10. As the vehiicle continues to move in the direction of arrow 244 in Figure 4, cam follower 184 engages cam element 216 forcin~ it outwardly awa~ from drive shaft 18. Eventually, cam follower 184 moves past the inclined surface of cam element 216 and cam element 216 moves back to the position shown in Figure 4 as a result of the tension of spring 226. In this position, it can be seen that cam follower 184 is held between cam elements 214 and 216. Cam follower 168 is in contact with surface 188 and as a result, the vehicle 10 is positively stopped and latched in such position.
Vehicle 10 resumes its travel by actuating air cylin-ders 236 and 202 so as to retract their piston rods 240 and 206 sequentially. When this occurs, cam elements 214 and 216 are forced outwardly away from drive shaft 18. Cam follower 184 is thus freed fro~ between cam elements 214 and 216. Vehicle 10 travels in the direction of arrow 244 and drive wheel 24 is biased back to its angular position by spring 136. After cam follower 168 is free of bar 192, cylinder 202 actuates to retract its piston rod 206, thereby lowering cam element 186 downwardly to position shown in phantom in Figure 3. Actuation of cylinders - 236 and 202 in sequence may be manual or automatic by use of a timer device.
While the queuing station has been described as being actuated by air cylinders 202 and 236, other equivalent devices such as solenoids may be used in their place. In addition, the details of the hydraulic or fluid system for actuating cylinders 202 and 23~ have not been specifically described since they will be readily apparent to one of ordinary skill in the art. It should also be readily appsrent that the queuing station can be located on either side of drive shaft 18 since the control mech-1 anism including cam plates 156 and 162 and cam followers 168 and 172 and the cam followers 182 and 184 for positively stopping the veh:icle 10 are arranged symmetrically about the center line of the system. It should further be readily apparent that the queuing station functions in the same manner to stop a vehicle 10 regardless of the direction in which it is moving.
The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, reference should be made to the ap-pended claims, rather than to the foregoing specification as indicating the scope of the invention.

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Claims (7)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLU-SIVE PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. Apparatus comprising a vehicle having a portion for supporting a load, said vehicle being mounted on wheels adapted to ride on a track, a drive wheel means on the bottom side of said vehicles and extending downwardly therefrom, said drive wheel means including a drive wheel oscillatable about an upright axis between a drive position and a stop position, said drive wheel being rotatable about a horizontal axis, a control member coupled to said drive wheel for oscillating said drive wheel about said upright axis, said control member being mounted for oscillation between a vehicle drive position and a vehicle stop position, said control member being movable in response to an actuator external of the vehicle, a stop element for limiting the extent to which said control member may oscillate, said stop element being on the bottom side of said vehicle and rigidly connected thereto, each of said drive wheel and control member being entirely below the elevation of the lowermost part of said wheels upon which said vehicle is mounted.

2. Apparatus as claimed in claim 1 including a second control member coupled to said drive wheel for oscillating said drive wheel, said second control member lying above the eleva-tion of the lowermost part of said wheels upon which said vehicle is mounted and said second control member being mounted on said vehicle for movement between a vehicle drive position and a vehicle stop position.

3. Apparatus as claimed in claim 2 wherein said second control member extends forwardly of said vehicle and includes a bumper means for said vehicle whereby movement of said bumper means toward its vehicle stop position causes oscillation of said drive wheel towards its vehicle stop position.

4. Apparatus as claimed in claim 1 including at least one member supported by the bottom side of said vehicle for cooperation with a latch means for holding the vehicle in a stopped position.

5. Apparatus in accordance with claim 1 including first and second guide members in a central portion of the vehicle, and first guide member extending downwardly from a front portion of said vehicle, said second guide member extending downwardly from a rear portion of said vehicle, said guide members extend-ing downwardly for a distance which is below the elevation of the lowermost portion of said vehicle wheels so that said guide members can extend into a guide slot for said drive wheel means, said guide members being on opposite sides of said drive wheel means.

6. Apparatus in accordance with claim 1 wherein said load supporting portion includes parallel rollers, the longi-tudinal axes of said rollers lying in a plane inclined to the horizontal, and a limit stop on said vehicle adjacent the roller having the lowermost longitudinal axis.

7. Apparatus in accordance with claim 6 wherein the axes of said rollers extend longitudinally of said vehicle so as to be generally perpendicular to the axes of rotation of said vehicle wheels.