Motorized Suspended Trolley

Abstract

A trolley or traction device for a suspended transportation or monorail system which comprises a column suspended from a roller train movable along the rail. The column supports a slidable collar carrying a pair of symmetrically arranged wheels, the collar being biased by a spring to urge the drive wheels upwardly into engagement with the rail. The spring seats against an abutment on the column which is releasable to cause disengagement of the drive wheels from the rail.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention.

The present invention relates to a trolly or traction device for a suspended transportation or monorail system.

2. Description of the Prior Art.

One previously proposed monorail traction device includes an electric motor and serves to move along the rail a pulley-block or a series of balancing devices supported on rollers carried by the rail. In the case of damage or accident, it is necessary to be able to disconnect the traction device very quickly to separate it from the other parts of the conveyor thus formed. The traction device comprises a single tired wheel mounted on a small bridge or bissel suspended from two trains of rollers, disengagement being obtained by lowering one of the hooking points of the bridge by means of a cam device. However the wheel is mounted in the middle of the bridge and moves downwardly by a distance which is equal to half the throw of the cam whereby disconnection is not readily effected. Additionally, the bissel device incorporating a single central wheel cannot be used with monorails having curved portions with a relatively small radius of curvature. In curved portions where the point of contact between the wheel and rail is in the center of the chord between the rolling points of the rollers, in spite of the width of the tire, the center of the chord may lie outside the circumferential surface of the tire so that the traction device increasingly leans or oscillates, particularly if there are inflexions in the curved portions. In addition, the weight of the previously proposed device is relatively high, as a result of which, to replace it in running position after disconnection, an effort is required which exceeds the average strength of a man acting either directly upon the chassis of the device, or through a control rod system.

SUMMARY OF THE INVENTION

According to the invention, there is provided in a trolley or traction device for a load suspended from a flanged monorail, roller means movable along the rail, column means suspended directly from the roller means, supporting means slidable along the column means, symmetrically arranged tired drive wheels carried by the supporting means, resilient means operative to bias said supporting means upwardly whereby to urge the drive, wheels into engagement with a rail opposite the roller means, means for rendering said resilient means inoperative, mounting means carried by the column means, drive motor means mounted on said mounting means, and transmission means coupling the drive motor means to the drive wheels.

In one preferred form of device tired wheels are arranged to contact flanges of the rail and are kinetically connected with a motor, and a column supports the motor via a bracket and is suspended directly from a roller rolling-axle, which rollers bear upon the flanges of the rail, said column supporting, through a collar, the axles of the two tired wheels which are pressed against the flanges and opposite the rollers by at least one spring. The bracket supports the motor in front of the axles of the tired wheels, and also carries reduction gearing and drive pinions, the pinions being connected to the said axles by flexible transmission means which can accompany the axes of the axles in their sliding movement along the column.

The bracket is located in relation to the column so that in the engaged condition of the wheels, the center of the wheels is higher than the drive pinion so that the transmission means is taut, while in the disengaged condition, the transmission means will be relatively unstressed.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying diagrammatic drawing in which:

FIG. 1 is a side elevation of a traction device in accordance with the invention;

FIG. 2 is a fragmentary front elevation to an enlarged scale of the device; and

FIG. 3 is a fragmentary side elevation, to an enlarged scale, of a modified form of the device.

DESCRIPTION OF THE PREFERRED EMBODIMENT

As shown in FIGS. 1 and 2, a traction device comprises a column 3 suspended from the center of a roller train 2 movable along spaced flanges 1a and 1b of a rail 1. A collar 4 slidable along the column 3 acts as a support for the axles 6 of two wheels 7 having solid or pneumatic tires. The axles 6 also mount, between the wheels 7, a pair of sprocket wheels 8 engaging respective drive chains 9. The collar 4 is resiliently biased upwardly by a spring 10 which surrounds the column 3 and abuts against a seat in the form of an annular disc 11. The disc 11 is supported on an abutment 12 in the form of a removable cotter pin passing transversely through an aperture in the column 3. The disc 11 comprises a number of radial projections 13, for example six projections 13, enabling the disc 11 to be grasped more easily by hand. The pin 12 can be withdrawn from the aperture by a flexible link 14 passing over a pulley on a bracket 16 and carrying a handle 15.

The bracket 16 is fixed to the column 3 by a collar device 17. The construction of the collar device 17 is known and will not be described in greater detail. An arm of the bracket 16 defines a platform 18 which mounts a drive motor assembly substantially at the height of the collar 4. The drive motor assembly comprises a motor 10 and a speed reducer 20 which has two output drive sprockets 21, each sprocket 21 driving a respective chain 9. The drive transmission system can alternatively comprise drive belts disposed around pulleys on the axles 6.

As shown in FIG. 2 the wheels 7 are inclined and converge upwardly towards the center of the rail, this inclination having been exaggerated in FIG. 2 for the sake of clarity. This 37 slanting""or cambering of the wheels tends to counteract the tendency of the vehicle to tack. In addition, if the vehicle moves in only one direction along the rail 1 the wheels 7 can converge in the direction of movement to improve stability. Further, to facilitate steering, the axis of the roller train 2 and of the column 3 can be staggered to the rear of the point of intersection of the axis of the axles 6.

To disengage the wheels 7 from the rail 1, the pin 12 is withdrawn from the aperture in the column 3 and the spring 10 forces the disc 11 downwardly along the column 3 into contact with stop pins 22 mounted on the column 3. The wheels 17 and their associated fittings likewise move downwardly out of engagement with the rail 1 and are spaced from the underside of the rail by two or three centimetres. Re-engagement is effected by raising manually the disc 13 and replacing the cotter-pin 12.

The device shown in FIG. 3 is mounted between two vertical parallel plates 23 supported by the base of the bracket 16. Right-angle cranked levers are pivotal about respective axes symmetrically arranged on opposite sides of the column 3. In each cranked lever, one arm 24 constitutes a catch engaging the underside edge of a spring seat 13 (equivalent to the disc 11 of the first embodiment) and has a nose portion with an undercut inclined portion 26; the other arm 25 is forked and embraces the column 3. The adjacent ends 27 of the arms 25 of the two levers are parallel and engage, the assembly thus forming a knuckle-joint held locked by the pressure of the spring 10 on the seat 13. Each of the arms 25 is biased by a spring 28 attached to one of the plates 23 to prevent excessive outwards pivotal movement of the levers. A lever 30 having forked end portions is pivotal on a transverse shaft 29, the forked end portions engaging pins 32 carried by a ring 31 slidable along the column 3. The lever 30 suitable carries an actuating handle 35.

To disengage the wheels of the device from the rail, the lever 30 is pivoted so that its forked end portions raise the ring 31 which strikes the knuckle-joint and opens it so as to release the levers 24 from the seat 13. The latter descends under the bias of the spring 10 and the wheels likewise descent. On moving downwardly, the seat 13 lies between the inclined portions 26 of the arms 24 and holds the arms 24 apart against the bias of the springs 28; downwards movement of the seat 13 is limited by stop pins 22 on the column 3. Re-engagement of the wheels can be effected by raising manually the seat 13. The column 3 can be hollow to receive a slidable piston 33 provided with a handle 34. The piston 33 is provided with two or three pins 36 passing through slots in the wall of the column 3, the pins 36 being engageable with the seat 13; thus by raising the piston 33 the seat 13 will also be raised. In this manner raising of the seat 13 is facilitated.

The device described can be utilized with various types of suspended monorail vehicles and tracks. The tracks can be in the form of an enveloping rail with a central slit and internal flanges (as particularly described) or in the form of a profiled rail with external flanges. The device is advantageous in that the tired wheels engage the rail directly opposite to the points of contact between the rollers and the rail, and that the disengagement action is exerted only on the wheels and their associated parts.

In the device particularly described, the adherence and the stability of the device are improved in relation to the previously proposed device and are relatively constant, whatever the outline of the monorail may be; moreover the disengagement assembly is very easy to handle both for disconnection and the re-connection to the wheels. Accordingly, the device described can be used with relatively large monorail vehicles.

Claims

What is claimed is:

1. In a suspended transportation system having at least one flanged track portion, a trolley, which comprises:

a. roller means movable on a first side of said at least one flanged track portion;

b. drive wheel means selectively supported in resilient movable engagement with a second side of said at least one flanged track portion substantially opposite said roller means and operative to move therealong when rotated;

c. means for operatively supporting said drive wheel means in said resilient movable engagement with said second side including

i. column means connected to said roller means,

ii. slidable means mounted on said column means for slidable movement therealong and carrying said drive wheel means, and

iii. resilient means for urging said slidable means along said column means for said resilient movable engagement of said drive wheel means with said second side, including means operative to selectively permit non-resilient movement of said slidable means along said column means.

2. In a suspended transportation system, a trolloy as claimed in claim 1, and wherein said drive wheel means includes at least two wheels and said supporting means further comprises axle means for securing said at least two drive wheels to said supporting means cambered with respect to said second side.

3. In a suspended transportation system, a trolley as claimed in claim 1, and wherein said resilient means comprises:

a. seat means slidable along said column means;

b. first spring means interposed between said slidable means and said seat means; and

c. abutment means for engaging said seat means to prevent movement thereof in one direction along said column means operative to bias said first spring means for said urging of said slidable means along said column means.

4. In a suspended transportation system, a trolley as claimed in claim 3, and wherein said abutment means is releasable for selectively permitting said non-resilient movement of said slidable means, and which comprises first pin means mounted on said column means and flexible linkage means actuable to withdraw said first pin means, and wherein said seat means comprises a plurality of projections.

5. In a suspended transportation system, a trolley as claimed in claim 3, and wherein said abutment means is releasable for selectively permitting said non-resilient movement of said slidable means, and which comprises:

a. lever means operatively connected with said column means to form a knuckle-joint, said lever means including arms operative to engage said seat means;

b. second spring means for biasing said arms inwardly towards said column means; and

c. pivotal fork means on said column means, said pivotal fork means being operative when pivoted to move said arms outwardly away from said column means against the bias of said second spring means.

6. In a suspended transportation system, a trolley as claimed in claim 5, and wherein said column means is tubular and comprises longitudinally extending slots therein, said trolley further comprising piston means slidable in said column means and second pin means carried by said piston means projecting outwardly through said slots and operative to engage and move said seat means when said piston means is moved upwardly along said column means.

7. In a suspended transportation system, a trolley as claimed in claim 1, and wherein said trolley further comprises:

a. mounting means carried by said column means;

b. drive motor means mounted on said mounting means; and

c. transmission means coupling said drive motor means to said means.

8. In a suspended transportation system, a trolley as claimed in claim 7, and wherein said drive wheel means includes at least two wheels and said supporting means further comprises axle means for securing said at least two wheels to said supporting means and wherein said transmission means comprises sprocket means rotatable with said axle means, and drive chain means entrained around said sprocket means.

9. In a suspended transportation system, a trolley as claimed in claim 7, and wherein said drive wheel means includes at least two wheels and said supporting means further comprises axle means for securing said at least two wheels to said supporting means and wherein said transmission means comprises pulley means rotatable with said axle means, and drive belt means extending around said pulley means.

10. In a suspended transportation system, a trolley as claimed in claim 7, and wherein said transmission means further comprises

speed reducing means driven by said drive motor means, said speed reducing means being mounted on said mounting means and including

output drive means, and wherein said drive wheel means includes at least two wheels and said support means further comprises axle means for securing said at least two wheels to said supporting means and wherein said transmission means comprises

a flexible drive transmission member interposed between said output drive means and said axle means, said mounting means being so positioned that when said drive wheels are resiliently engaged with said second side, the center of said drive wheels is located above said output drive means and said flexible drive transmission member is taut, and when said drive wheels are moved away from said second side, said flexible drive transmission member is relatively unstressed.