GB2123369A - Conveying apparatus - Google Patents

Abstract

Conveying apparatus comprises a single overhead rail 1 along which travels a vehicle 3 having trolleys 6%, 8% connected to a common carrier member 11 from which articles to be conveyed are suspended, each trolley being pivotable about a vertical axis relative to member 11 and being equipped with a main running wheel, e.g. 4, and two pairs of auxiliary guide wheels, e.g. 41f, 42f, 41r, 42r, to front and rear of the main wheel. A main wheel of the vehicle is driven by a motor 7 powered by batteries on the member 11. The motor may be controlled by an optical remote control unit 100 in conjunction with a sensor 102 and associated circuitry on the vehicle, and track mounted magnets 35 may be provided cooperating with a reed switch on the vehicle to stop the motor. The vehicle may have pick-ups engageable with feeder electrodes provided at a station on the rail, in order to charge the vehicle batteries. <IMAGE>

Description

SPECIFICATION Conveying equipment Background of the invention (1) Field of the invention This invention relates to an overhead conveying equipment.

(2) Description ofthe prior art Various conveying equipments have hitherto been put into practice which hangs its vehicle from an overhead rail and travels therethrough, the overhead rail often employing a monorail due to its simple construction. The monorail construction, however, provides an auxiliary rail for preventing sideway swinging or derailment of a conveying vehicle, thereby being large-scaled. Therefore, in a case of using such construction in a shop often changing the layout of equipment, there has been created the problem in that it takes much time to change the conveying route.

It is more difficult for the monorail provided together with a feed line to change the conveying route. While, the equipment, when loading batteries on the vehicle, requires no feeder line, but is defective in that exchange or charging of batteries is troublesome.

The remote control is desired to operate the vehicle to travel or stop, but in a case of using electric waves as the communication medium, various electric circuits in the shop are subjected to noise fault, whereby the light, such as the infrared rays, is desired to be used as the communication medium, but photo signals cannot be transmitted when a light receiving unit usually provided at the vehicle enters into the dead angle, thereby being restricted in the use within the shop arranging therein many obstacles to the light.

This kind of equipment often allows the conveying vehicle to move or stop as predetermined, such as reciprocation between the predetermined points or a stop at the station, other than the above remote control. In this case, a switch dog complicated in construction and of high accuracy has conventionally been used for the assignment of position, which has been defective in that it takes much time to adjust or change its mounting position.

Objects ofthe invention In the light of the above problems, this invention has been designed.

A first object of the invention is to provide a conveying equipment simple in construction of using only one rail and easy to install or dismantle, thereby being useful for the conveying line when higher in the frequency of change or required to be temporarily provided.

A second object of the invention is to provide a conveying line along which a conveying vehicle stably and smoothly travels even when the conveying route is curved as well as straight.

A third object of the invention is to provide a conveying equipment easy to set or change stations orturning points.

Afourth object of the invention is to provide a conveying equipment whose batteries serving as a power source, after discharged, can be charged without dismounted from the vehicle while being kept hung on the rail.

A fifth object of the invention is to provide a conveying equipment provided with the remote control function of easy operation.

The above and further objects and features of the invention will more fully be apparent from the following detailed description with accompanying drawings.

Brief description of the drawings Figure 1 is a perspective view of an embodiment of a conveying equipment of the invention, when view from below, Figure 2 is a side view of a conveying vehicle thereof, Figure 3 is a front view of the same, Figure 4 is a view exemplary of wheels at the conveying vehicle, Figure 5 is a side view of a feeder and collectors, Figure 6 is a front view of the feeder and collectors, Figure 7 is a circuit diagram of an electric circuit of the invention, Figure 8 is a schematic front view exemplary of a magnet unit, Figure 9 is a plan view thereof, and Figure 10 is a front view of the magnet unit in condition of being mounted on a rail.

Detailed description of the invention Referring to Figures 1,2 and 3, a rail 1 of round pipe is supported to the overhead structure, such as a ceiling our a girder through a number of supporting members 2 of about C-like shape as shown. The supporting members 2 all are positioned at one side of rail 1 not to hinder a conveying vehicle 3 from travelling, and are adapted to contact at the lower ends with the lower peripheral surface of rail 1 to thereby rigidly fix it. Alternatively, the supporting members 2 may extend downwardly onesidely from - the rail 1 and support it from below.

The conveying vehicle 3 hung on the rail 1 comprises front and rear wheel units and a vehicle body connecting them, suspended from the rail 1.

The arrangement and configuration of wheel are important for the wheel units of the invention, which need not provide an axiliary rail conventionally used for anti-swing, thereby enabling stable running of vehicle 3 through the single rail 1.

Figure 4 shows the arrangement and configuration of each wheel of the vehicle 3, in which main wheels 4 and 5 each of hour-glass-like shape rotatably contact with the upper side of rail 1 and sub-wheels 41f, 42f, 51f and 52f (41 r, 42r, 51 rand 52r) each of short columnar shape are positioned in front (or at the rear) of each main wheel 4 or 5 and contact rotatably with both lateral sides of rail 1 respectively, the front main wheel 4 being called the driving wheel and the rear wheel 5, the driven wheel in this embodiment.The respective wheels are made from, for example, rubber or synthetic resin, and main wheels 4 and 5 are in close contact with the rail 1 by the load applied to the vehicle 3, but the right sub-wheels (41f through 52f and 41 r through 52r) for preventing the swinging motion are adapted to contact with the rail 1 through some clearances in consideration of the curvature of the curved rail 1 respectively.In addition, pairs of sub-wheels 41f and 42f, 41 rand 42r, 51f and 52f, and 51 rand 52r, opposite to each other at both sides of rail 1 are symmetrical with respect to the center thereof, the front and rear sub-wheels 41f and 41 r, 42f and 42r, with respect to the main wheel 4 and sub-wheels 51f and 51 r, and 52f and 52rto the main wheel 5, are positioned at equidistances away from the main wheels 4 and 5 respectively.

A wheel shaft 62 is supported at its base end horizontally through a bearing 61 to the center of upper end of a front wheel shaft bearing member 6 and carries at the base end side a pulley 63 and at the fore end side the main wheel 4 keyed thereto. A wheel shaft mounting frame 64 about rectangular when viewed in plan is formed at the upper portion of wheel shaft bearing member 6 in a manner of enclosing the wheel shaft 62 and main wheel 4, the wheel shaft 62 being supported at the utmost end thereof through a bearing 65 to the portion of frame 64 opposite to the wheel shaft bearing member 6.

The wheel shaft mounting frame 64 is provided at the four corners with vertical spindles through which the sub-wheels 41f, 42f, 41 rand 42r are rotatably supported.

To the lower portion of wheel shaft bearing member 6 is mounted an electric motor 7 so that its rotary shaft extends in parallel to the wheel shaft 62, its rotary shaft is positioned at the wheel shaft bearing member 6 side, and its trunk extends in the extending direction of wheel shaft 62, the motor 7, rotatably driving a pulley 71 through reduction gears (not shown). Pulleys 71 and 63 both are toothed and a cogged belt 72 is carried across the pulleys 71 and 63, the main wheel 4 being rotatably driven by the motor 7 through the belt 72.

A wheel shaft bearing member 8 at the rear side is simple in construction because the motor 7 need not be provided, in which the main wheel 5 is keyed to a wheel shaft rotatable and parallel to the wheel shaft 62 and the sub-wheels 51f, 52f, Sir and 52r are supported rotatably to vertical spindles provided at the four corners of a rear main wheel shaft bearing member 8 and positioned below the main wheel 5, the main wheels 4 and 5 and belt 72 being covered by ornamental covers 6' and 8' for dust-proof.

Shafts 66 and 86 extend vertically downwardly from the lower portions of wheel shaft bearing member 6 and 8 and connect at the lower end portions a loading beam 9 in relation of being rotatable in association with the shafts 66 and 86, the loading beam 9 connecting the front and rear wheel units and supporting a hanging load, and nuts 67 and 86 screw with screw threads at the lower ends of shaft 66 and 86 respectively, thereby locking the loading beam 9. The loading beam 9 turns the position just below the centers of main wheels 4 and 5 with respect to the wheel shaft bearing members 6 and 8 respectively.

The loading beam 9 comprises a horizontal portion 91 of proper width and one or a plurality of vertical portions 92 for reinforcement of horizontal portion 92, and is provided at both lengthwise ends with tubular portions 93 and 94 fitted onto the shafts 66 and 86 respectively, the vertical portions 92 hanging therefrom slings 95 and 96, the horizontal portion 91 providing a proper bracket on which batteries are loaded detachably. Also, a cover 11 is mounted to the loading beam 9 by use of supporting member (not shown) and covers the batteries 10 and an electric circuit (in Figure 7) to be discussed below, a control board 12 being mounted to the cover 11 at the left side in Figure 2.

At the front of cover 11 is mounted an photo switch 97 of regressive reflected light detection type provided with light-emitting and sensor eye, and to the rear of the same is stuck a reflector 98 used for a photo switch 97 at another conveying vehicle.

Also, at the lower surface of cover 11 is mounted a photo sensor 101 which keeps a sensor eye 102 facing downwardly, and at the upper surface of the same is mounted a reed switch 34 in the position facing the lower surface of rail 1,a remote control unit 100 being adapted to generate by the infrared rays signals corresponding to the contents of operation. Furthermore, the cover 11 is provided at the upper surface with bores not to hinder the wheel shaft bearing members 6 and 8 and ornamental covers 6' and 8' from rotation with respect to the cover 11 or loading beam 9, and at the lower surface with bores through which the slings 95 and 96 are inserted, the slings 95 and 96 being used for hanging a load container 99.The conveying vehicle 3 constructed as above mentioned determines arrangement of each component so as to keep the center of gravity of vehicle 3 on the plane including the center of the axial direction of the respective main wheels 4 and 5.

Atthe predetermined position of rail 1 is provided a station for charging the secondary cells chargeable, i.e., the batteries 10, which station may be exclusive for charging, or utilize a loading and unloading point or a stand-by point for the branch of rail 1, the station providing a feeder 204 as shown in Figures 5 and 6, the vehicle 3 carrying a collectors 205 in slidabie contact with the feeder 204.

At first, explanation will be given on the feeder 204. Referring to Figure 5, a base plate 241 of insulating material, such as synthetic resin, is rounded at both ends in the moving direction (longitudinal) of vehicle 3, sledge-like-shaped when viewed from the side as shown, curved in a circular arc at both lateral sides, and has about a half length of vehicle 3. Magnets 242,242 are fixed to the upper surface of base plate 241 at both lengthwise ends thereof, by which the feeder 204 is magnetically stationary at the lower surface of rail 1 at the position to be the station. Grooves 243, 243 each of proper depth and proper width are formed at the lower surface of base plate 241 and positioned near both lengthwise ends thereof and at the widthwise centers of the same, so that feeder electrodes 244, 244 of brass are fixedly fitted into the grooves 243, 243 in relation of being level with the lower surface of base plate 241 respectively. Also, the base plate 241 has at the upper surface bores perforating toward the electrodes 244, 244, through which bores lead wires 245,245 connect with the electrodes 244,244 respectively.

While, the collectors 205 are bolted on the upper surface of cover 11 at the portions thereof just below the rail 1 and spaced longitudinally of cover 11 at an distance about equal to a distance between the centers of feeder electrodes 244,244. At each collector mounting portion, a clamp 251 of brass abuts against the upper surface of cover 11, a metal fitting 252 abuts against the inner surface of the same, and a bolt 253 is inserted through bores formed at the clamp 251, cover 11 and fitting 252 and screwably tightened by a nut from inside cover 11, thereby fixing each collector 205, the clamps 251 each comprising a thick rectangular base 251 a and a flat holder 251 b to thereby fixedly sandwich therebetween an elastic member 254 serving as the collector 205.Each elastic member 254 is formed of a flat elliptic plate of phosphor bronze, bent downwardly at both ends in the major axis direction, and fixed at the lower portion as the above, and has at the top contact members 255 fixed thereto. Each clamp 251 divided vertically into two puts therebetween one end of lead wire 256 to be discussed below.

Referring to Figure 7, an electric circuit of the invention is shown, in which the positive electrode of batteries 10 connects with a positive line 10p through a main switch 21 and the negative electrode of the same with a negative line iOn, the positive electrode also connecting with one lead wire 256 through a diode having a cathode at the positive electrode side and for preventing a dead-shortcircuit, the negative electrode of batteries 10 connecting directly with the other lead wire 256.

Reference numeral 261 designates a commercial power source, the power from which is dropped to desired voltage by a transformer 262, the secondary low voltage thereof being given to a rectifier 263, and an output therefrom being given to the feeders 204,204 from the lead wires 245, 245 through a floating charge controller 264,.

Between the positive line 10p and the negative line 1 On are connected a series circuit of normally open contact 23a of a keep relay 23, the electric motor 7, a normally closed contact 24b of a keep relay 24, and resistance 25 for speed reduction, both the contacts 23a and 24a being closed to provide the connection to normally rotate the motor 7. A normally closed contact 23b of keep relay 23 is connected between the node of contact 23a and of a first terminal 7a of motor 7 and the node of contact 24b and resistance 25, and a normally open contact 24a of keep relay 24 is connected between the node of contact 24b and of a second terminal 7b of motor 7 and the positive line 10p, the contacts 24a and 23b closing to provide the connection to reversely rotate the motor 7.The resistance 25 connects in parallel with a normally open contact 26a of an electromagnetic relay 26 and is adapted to be closed to rotate the motor 7 at high speed. A series circuit of a diode, resistance and an ampere-hour meter 37, is connected between the second terminal 7b of motor 7 and the negative line 10n, the ampere-hour meter 27 being mounted visibly to the control board 12 so as to display by use of the electroplating phenomenon an amount corresponding to the product of an exciting current (an exciting current for motor 7 in this embodiment) and a current-carrying time, the meter 27 itself being the well-known element. A series circuit of a diode, a switch 28, a voltage regulator IC 29, and a melody IC 30, is provided between the first terminal 7a of motor 7 and the negative line 1 On, so that when the switch.

28 is closed and the motor 7 is energized, the melody IC 30 generates the predetermined melody to alarm running of vehicle 3.

The keep relays 23 and 24 are connected with the positive line 10p, push button switches 31 and 32 for operating the normal or reverse rotation of motor 7 are operation with keeping signal terminals of keep relays 23 and 24 respectively, and a push button switch 33 for operation a halt of vehicle 3, a reed swich 34 and a photo switch 97, are connected to release signal terminals of the same, these switches 31,32,33 and 34 being connected at both ends to the negative line iOn, the switches 31,32 and 33 also being mounted on the control board 12.

The remote control unit 100, the photo sensor 101 and a decoder 103, employ INFRAFERN (trade name) FSE541 manufactured by Siemens co. in West Germany, the remote control unit 100 being provided with four push botton switches 100a, 100b, 100c and 100d to thereby generate 2-phase code signals in the infrared rays corresponding to operation of each bottom switch. The photo sensor 101 receives the signals in the infrared rays through the photo sensor unit comprising a lens and a photodiode, so that the signals are photoelectrically converted and then given to a decoder 103.The decoder 103 is interposed between the positive line 10p and the negative line iOn and reads input signals from the photo sensor 101 to allow each output terminal 103a, 103b, 103c or 103d at the decoder 103 to have a low level (the level of negative line 10n) corresponding to operation of each switch 100a, 100b, 100e and 1 old, the output terminals 103a and 103c connecting with the keeping signal terminals of keep relays 23 and 24 respectively, the output terminal 103b connecting with the release signal terminals of keep relays 23 and 24, and the output terminal 103d connecting with the positive line 10p through an exciting coil 26c at an electromagnetic relay 26.

The conveying equipment of the invention constructed as the abovementioned is used by keeping the vehicle 3 suspended from the rail 1 and hanging a load container 99 from the slings 95 and 96. In the state where the main switch 21 is closed, when the switch 31 or 32 is pushed, the keep relay 23 or 24 keeps its actuating condition, the contacts 23a and 24b, or 24a and 23b, are closed to normally or reversely rotate the motor 7, and the vehicle 3 moves forwardly or rearwardly, during which time the melody IC 30 gives a melody alarm and the amperehour meter 27 carries out the timing by the energized motor 7 to thereby display the operating time. The switch 33 is pushed to release the keep relay 23 or 24 from actuating condition, and the contact 23a or 24a is open to stop the rotation of motor 7, in turn the running of vehicle 3.In a case where the vehicle 3 is intended to stop at the particular position on the rail installation route, a permanent magnet 35, as shown in Figure 1, is previously mounted to the lower peripheral surface of rail 1 by use of a proper means.

Then, the reed switch 34 mounted on the upper surface of cover 11 operates (closes) upon arriving just below the permanent magnet 35, so that the keep relays 23 and 24 are released to stop the rotation of motor 7. In a case where a plurality of conveying vehicles 3 are suspended from the rail 1 (in this case, the vehicles 3 usually are movable forward only), the light emitted from the photo switch 97 at one vehicle 3 is reflected by the reflector 98 at another vehicle ahead of the one vehicle 3 and detected by the photo switch 97, which is actuated to stop the motor 7, thereby avoiding a rear-end collision between the two vehicles 3.

On the other hand, in a case of operating the remote control unit 100, the switch 100a or 1 00c is operated to allow the output terminal 103a or 1 03c at the decoder 103 to have a low level so that the keep relay 23 or 24 is put in operating condition and the motor 7 rotates normally or reversely, thus moving the vehicle 3 forwardly or backwardly. During this time, upon operating the switch 100d, the decoder output terminal 103d has a low level and an exciting coil 26c is energized to close the contact 26a and the resistance 25 is bypassed. Hence, the motor 7 increases the speed to allow the vehicle 3 to run at high speed. Upon operating the switch 100b, the decoder output terminai 103b has a low level so that the keep relay 23 or 24 is released from actuating condition and stops the motor 7.

During the use of remote control unit 100, its infrared ray emitting unit is preferable to be operated facing the sensor eye 102 provided at the lower surface of cover 11, the infrared rays reflected from the every direction being extremely readily received by the sensor eye 102 provided as the above, whereby as far as the conveying equipment of the invention is used indoors, the remote control unit 100, when in an operable range defined by the specifications of the unit 100 and photo sensor 101, is operable without taking care to the infrared ray projecting direction. While, even when in outdoor use, in a case of surrounding the rail 1 by walls or the like, the remote control unit 100 is operable regardless of any projecting direction of the light because the reflected light from the wall, the floor or the ground, can be sensed.Also, in a case where the light of moderate intensity is expected to be reflected from the floor or ground even if no surrounding exists, the remote control is performable by projecting the light toward the vehicle 3 or the floor or ground at an intermediate position between an operator and the vehicle 3.

The reason of obtaining such effect is that in a case of providing the sensor eye 102 as the invention, its visual field leads to expansion in an about hemispheric range below and around the vertical, resulting in the state where the reflected light from the surroundings is sensible with ease. The conventional vehicle mounted a photo sensor on the side thereof, when compared with the invention, cannot sense the reflected light from the rear (the reverse side) and includes in the visual field in part the upper range where the reflected light is less than that in the lower range, which is useless. Also, the sensor eye 102, when provided at the upper surface of cover 11 at the vehicle 3, the upper visual field is useless to reduce an effective visual field. Hence, the provision of sensor eye 102 as the invention is the most effective.

In addiction, it is a matter of course that expansion of the light beam projected from the remote control unit 100 contributes to attain the above effect.

Also, the light sensor unit of the invention need not be mounted inevitably to the lowermost portion of vehicle 3 and face vertically downwardly, but may at need slightly slant the optical axis of the same.

Alternatively, a lens of light sensor of the invention may face one ends of optical fibers and the other ends thereof may be mounted to the photoelectric conversion element.

Now, explanation will be given on operation of wheels at the vehicle 3 during its running. The right-hand and left-hand sub-wheels, when the vehicle 3 runs along the straight rail 1, roll in properly rotatable contact with the lateral peripheries of rail 1 to restrict the laterally swinging motion of vehicle 3.

The loading beam 9 at a curved portion of rail 1 is positioned in the mode of being a chord to the arc and the wheel shaft bearing members 6 and 8 turn around the tubular portions 93 and 94 at the loading beam 9 corresponding to the position thereof, at which time each sub-wheel is subjected to lateral pressure to thereby be brought into press contact with the rail 1 due to its curve, thus reducing the speed of wheel of itself and strengthening its engagement with the rail 1 to raise safety in the vehicle's running.

Alternatively, the rail 1 may employ a pipe square in section. In this case, the main wheels 4 and 5 in contact with the upper surface of rail 1 need only be sand-glass-like-shaped similarly to the sub-wheels, which is effective as the same as the use of round pipe.

Also, the container 99 hung from the loading beam 9 may alternatively be replaced by a box provided at a trailer connected to the wheel shaft bearing member 8, cover 11 or loading beam 9 and driven along the rail 1 for conveying loads. In this case, a plurality of trailers may of course be connected for use, the loading beam 9 may be provided with gripper or the like to be given the hoist function, or the cover 11 itself may provide a space for containing the object to the conveyed.

Now, after repeating the vehicle's running as the above, voltage of batteries 10 drops to make impossible the running at a desired speed, at which time the vehicle 3 is stopped at the station where the feeder 204 is mounted to the rail 1,so that the contacts 255 at the collectors 205 are brought into contact with the electrodes 244, 244 of the feeder 204, and then the power source 61 or floating charge controller 264 starts to charge the batteries 10.

During the above charging, the control circuit for the motor 7 is energized by the batteries 10 to enable control of motor 7, such as keeping it to a halt, and also the vehicle 3 can travel from the station by the remote control. Furthermore, a hoist other than the motor 7, when provided at the vehicle 3, can be driven by the batteries 10. In brief, the advantage of floating charge can be given. In addition, the feeder 204 and collectors 205 may alternatively be juxtaposed in each pair laterally of vehicle 3.

Also, since the feeder 204 is attached to the rail 1 by means of magnets 242, the station is easy to move.

Next, explanation will be given on the magnet 35 used to set the station for charge or others, in other words, the position where the vehicle 3 is stopped.

The magnet 35 may be bolted to the lower side of rail 1, but when mounted as discussed below, is readily and quickly changeable of its set position.ln detail, referring to Figures 8,9 and 10, reference numeral 301 designates a spacer, 302u and 302d designates iron plates, and 303a, 303b, 304a and 304b designate permanent magnets respectively. The spacer 301 is formed of a rectangular plate of non-magnetic material, such as plastic or the like, the iron plates 302u and 302d being rectangular equal to the size to the spacer 301 and fixed integrally thereto in a manner of sandwiching the spacer 301 between the plates 302u and 302d by use of adhesives.The permanent magnets 303a, 303b, 304a and 304b each are of equal size, have a length equal to width of each plate 302u or 302d, a width smaller than length thereof, and a thickness equal to that of the same; constituted to be the N-pole at the upper or lower half and the S-pole at the lower or upper half as shown; and fixed by use of adhesives integrally to the upper surface of plate 302u and the lower surface of plate 302d at the leftward and rightward ends thereof and spaced from each other at a proper distance.The magnet 303a of the upper S-pole and lower N-pole and that 303b of the upper N-pole and lower S-pole, are fixed to the upper surface of plate 302u, and that 304a of the upper S-pole and lower N-pole, and that 304b of the upper N-pole and lower S-pole, are fixed to the lower surface of plate 302d, so that the adjacent magnets 303a and 303b and those 304a and 304b are fixed to the plates 302u and 302d in relation of facing at the heterpoles respectively. Now, for example, where the magnets 303a and 303b at the upper surface of plate 302u are magnetically attached to the lower surface of rail 1 as shown in Figure 10, the magnetic lines of force are in condition as shown by the broken lines.In other words, the magnetic lines of force produced between the N-poles and the S-poles at the upper and lower surfaces of both the magnets 303a and 303b on the upper surface of plate 302u are within the plate 302u and'rail 1 functioning as the yoke, thereby causing no leakage flux on the way. On the other hand, the magnetic lines of force generated between the N-pole and the S-pole at the upper sides of magnets 304a and 304b disposed within the moving zone of reed switch 34 are produced within the plate 302d functions as the yoke not to produce the leakage flux. Hence, the magnetic lines of force between the N-pole and the S-pole at the lower side are produced widely downwardly and longitudinally of rail 1, whereby the reed switch 34 is reliably actuated when it reaches the magnet unit, thus obtaining the stable operation.

As this invention may be embodied in several forms without departing from the spirit of essential characteristics thereof, the present embodiment is therefore illustrative and not restrictive, since the scope of the invention is defined by the appended claims rather than by the description preceeding them, and all changes that fall within meets and bounds of the claims, or equivalence of such meets and bounds are therefore intended to be embraced

Claims (25)

by the claims. CLAIMS

1. A conveying equipment characterized by providing one overhead rail and a conveying vehicle, said vehicle having two main wheels which contact with the periphery of said rail from the upper side thereof and are disposed in the moving directions thereof and spaced at a proper distance, pairs of sub-wheels which are provided at the both side of the said rail and at the front side and the rear side of each of said main wheels in the moving direction thereof and contact with the periphery of said rail from the lateral side thereof respectively, an electric motor for driving at least one of said main wheels, an electric circuit for controlling rotation of said motor, batteries serving as a power source for said motor, and a connecting member connected horizontally rotatably to a wheel shaft bearing member for each of said wheels.

2. A conveying equipment as set forth in claim 1, wherein said rail has the round outer periphery.

3. A conveying equipment as set forth in claim 1, wherein said sub-wheels are adapted to be rotatable integrally with said main wheels with respect to said connecting member respectively.

4. A conveying equipment as set forth in claim 2, wherein said sub-wheels are adapted to be rotatable integrally with said main wheels with respect to said connecting member respectively.

5. A conveying equipment as set forth in claim 1, wherein said connecting member is constituted to support a hanging load.

6. Aconveying equipment as set forth in claim 2, wherein said connecting member is constituted to support a hanging load.

7. A conveying equipment as set forth in claim 3, wherein said connecting member is constituted to support a hanging load.

8. A conveying equipment as set forth in claim 4, wherein said connecting member is constituted to support a hanging load.

9. A conveying equipment as set forth in claim 1, wherein said electric circuit is provided with a reed switch disposed at the upper portion of said conveying vehicle and magnets for actuating said reed switch are attacked to said overhead rail.

10. A conveying equipment as set forth in claim 9, wherein said magnets are attached to said overhead rail by use of other magnets.

11. A conveying equipment as set forth in claim 1, wherein said batteries are secondary batteries.

12. A conveying equipment as set forth in claim 11, wherein said rail is provided with a feeder, said conveying vehicle being provided with a collector contactable with said feeder, so that said secondary batteries are adapted to be applied with floating charge through said feeder and collector.

13. A conveying equipment characterised by providing one overhead rail, an optical remote control unit, and a conveying vehicle having two main wheels which contact with the peripheral surface of said rail from the upper side thereof and are disposed in the moving directions thereof and spaced at a proper distance, pairs of sub-wheels which are provided at the both side of the rail and at the front side and rear side of each of said main wheels in the moving direction thereof and rotational contact with the peripheral surface of said rail from the lateral sides thereof, an electric motor for driving at least one of said main wheels, batteries serving as a power source for said motor, a connecting member connected horizontally rotatably to a wheel shaft bearing member for each of said main wheels, a photo sensor which receives an photo signal generated by said remote control unit and photoelectrically converts said signal, and an electric circuit for controlling rotation of said motor by means of said converted signal from said photo sensor, said photo sensor having its sensor eye positioned at the bottom side of said conveying vehicle.

14. A conveying equipment as setforth in claim 13, wherein said rail is round at the outer periphery.

15. A conveying equipment as set forth in claim 13, wherein each pair of said sub-wheels are rotatable integrally with each of said main wheels with respect to said connecting member.

16. Conveying equipment as setforth in claim 14, wherein each pair of said sub-wheels are rotatable integrally with each of said main wheels with respect to said connecting member.

17. Aconveying equipment as setforth in claim 13, wherein said connecting member is adapted to support a hanging load.

18. A conveying equipment as setforth in claim 14, wherein said connecting member is adapted to support a hanging load.

19. A conveying equipment as set forth in claim 15, wherein said connecting member is adapted to support a hanging load.

20. A conveying equipment as set forth in claim 16, wherein said connecting member is adapted to support a hanging load.

21. A conveying equipment as set forth in claim 13, wherein said electric circuit is provided with a reed switch disposed at the upper portion of said conveying vehicle, said overhead rail attaching magnets for actuating said reed switch.

22. A conveying equipment as set forth in claim 21, wherein said magnets are attached to said overhead rail by use of other magnets.

23. A conveying equipment as set forth in claim 13, wherein said batteries are secondary batteries.

24. A conveying equipment a set forth in claim 23, wherein said rail is provided with a feeder, said conveying vehicle being provided with a collector contactable with said feeder, so that said secondary batteries are adapted to be applied with floating charge through said feeder and collector.

25. A conveying equipment substantially as herein defined with references to the accompanying drawings.