Power Conductor Takeup System

Abstract

This invention relates to an improved system for providing power to the extremities of telescopable or expandable equipment comprising a fixed member and a movable member. A pulley system, independently movable with respect to the fixed and movable members, is rotatably transversed by a substantially lineal flexible power conductor. This power conductor is attached at one of its ends to a power source on the fixed portion of the equipment and at its other end to a power utilizing means on the movable portion of the equipment. Means are provided to move the pulley system in relation to the movement of the movable member so that the power conductor is held in a substantially taut condition throughout the range of movement of the movable portion of the equipment.

Parent Case Text

CROSS-REFERENCE

This application is a continuation-in-part of applicant's copending Ser. No. 858,298 application, filed Sept. 16, 1969, now abandoned for APPARATUS FOR PLACING CONCRETE MIX OR THE LIKE.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to an improved system for providing power to movable portions of expandable or telescopable equipment. More specifically, it relates to a system which requires a minimum length of power conductor and eliminates the necessity for expensive and unreliable slidable or rotatable fittings.

2. Description of the Prior Art

Movable or telescopable conveyor systems have been found to be extremely useful in the various operations involving the short-range movement of various materials such as grains, coal, gravel, and concrete mix. For example, conveyor belt systems for the conveyance of concrete mix are illustrated in Oury, et al., U.S. Pat. No. Re-26,298, reissued Nov. 21, 1967; Oury, U.S. Pat. No. Re-26,347, reissued Feb. 20, 1968; Oury, et al., U.S.. Pat. No. 3,343,651, issued Sept. 26, 1967; and in the Ser. No. 858,298 application of which this application is a continuation-in-part. As illustrated therein, a series of conveyor belt units can be combined to convey concrete mix to a particular area at the construction site where the mix is to be placed. Since it is more economical and expeditious to place as much concrete mix as possible before the conveyor system is moved, all of the above-references illustrate a movable or telescopable discharge conveyor at the end of the conveyor system to allow a greater area of coverage by the discharge conveyor.

In all of the above-illustrated conveyor systems, each individual conveyor apparatus is a self-contained unit. Consequently, each conveyor apparatus has a self-contained drive unit to propel the conveyor belt. Various types of drive units can be utilized including electric motors, hydraulic motors, or gasoline engines. However, because of the start-and-stop nature of the concrete pouring operation in construction, electric or hydraulic motors have been found to provide the greatest ease of operation.

Typically, at a construction site, power is provided by a gasoline engine driven electrical generator or hydraulic compressor. In either case, it is reasonably simple to extend either an electrical cable or a hydraulic hose along the stationary portions of the conveyor system to provide power to the individual conveyor drive units. However, problems have been experienced in providing power to the power drive unit contained on the final movable or telescopable discharge conveyor. If the electrical cable or hydraulic hose is long enough to provide power at the furthest extension of the telescopable conveyor apparatus, the cable or hose will have many feet of slack when the discharge conveyor is in its fully retracted position. Allowing the cable or hose to remain in a slack condition is extremely dangerous since workmen may become entangled or it may be severed or become tangled by other equipment being utilized at the construction site. One method of solving this problem is to provide a spring-loaded spool or reel arrangement which allows the feed out of the cable to the discharge conveyor as it is moved. However, such reel arrangements have not proved satisfactory since they require extremely expensive and unreliable slidable or rotatable fittings to provide power to the hose or cable on the reel as the reel is rotated.

Thus, it is the principal object of the present invention to provide simple and reliable power conductor take up system which allows power to be conducted to the extremities of expandable or telescopable equipment without limiting the range of motion of said equipment.

A further object of the present invention is to provide an improved power conductor takeup system which eliminates dangerous slack in the power conductor without the need for expensive or unreliable takeup spools or reels and related fittings.

A further object of the present invention is to provide a power conductor takeup system which is simple, reliable, economical, and adaptable to use on a variety of telescopable or expandable pieces of equipment.

SUMMARY OF THE INVENTION

The foregoing and other objects, advantages, and features of the subject invention may be achieved in expandable or telescopable equipment comprising a relatively stationary first base member with a power source thereupon and a second expandable or telescopable member with a power utilization means attached thereto adapted to engage and move relative to the first base member. An improved power conductor takeup system for such equipment comprises an independently movable pulley system; a substantially lineal flexible power conductor attached at one of its ends to said power source and at its other end to the power utilization means and adapted to engage and rotatably transverse the pulley system along its length; and a power conductor take up means adapted to move the pulley system so that the power conductor is held in a substantially taut condition throughout the range of movement of the second member.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side fragmentary elevational view of a crane-mounted conveyor system with a preferred embodiment of the present invention provided thereon.

FIG. 2 is a fragmentary end view of the conveyor frame and the carriage and pulley system.

FIG. 3 is a sectional view taken substantially along Line 3--3 of FIGURE 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With respect to the drawings, FIGURE 1 shows a concrete placement apparatus 10 comprising a base 12, a supporting assembly 14, a telescoping conveyor assembly 16, and a fixed conveyor assembly 18. Supporting assembly 14 comprises fixed member 15, and hydraulically expandable members 20 and 22 which can be extended to increase the length of supporting assembly 14.

The base 12 and support assembly 14 advantageously take the form of a hydraulic crane which is, per se, old in the art, and itself forms no part of the present invention. Further, the fixed conveyor assembly 18 and telescoping conveyor assembly 16 are disclosed and described in copending application, Ser. No., 858,298, filed Sept. 16, 1969, of which this application is a continuation-in-part. The details of the attachment and operation of the fixed conveyor assembly 18 and the telescoping conveyor assembly 16 are described in detail in the parent application.

As disclosed in the parent application, extension of hydraulically expandable members 20 and 22 of the supporting assembly 14 causes a corresponding telescopic movement of telescoping conveyor assembly 16 with respect to fixed conveyor assembly 18. A power hook-up assembly 30 is provided on the fixed conveyor assembly 18, and, depending on the type of power being utilized, assembly 30 may take the form of an electrical terminal box or a hydraulic junction box. Provided on the telescoping conveyor assembly 16 is a power utilization means 32 which, again depending on the type of power utilized, may take the form of either an electric motor or a hydraulic motor. Attached at one of its ends to the power hookup assembly 30 and at its other end to the power utilizing means 32 at point 33 is a substantially lineal flexible power conductor 34. Depending on the type to be conducted, power conductor 34 may take the form of either an electrical cable or an hydraulic hose. The purpose of the power conductor 34 is to transmit power from the power hookup assembly 30 to the power utilization means 32. The power conductor 34 is looped around and in circumferential engagement with a pulley system 36.

A takeup cable 38 is attached at one of its ends to the telescoping conveyor system 16 at point 40 and to the fixed conveyor assembly 18 at point 42. The takeup cable 38 is likewise looped around and in circumferential engagement with pulley system 36.

FIGURE 2 shows an end view of pulley system 36. Pulley system 36 comprises circular end plates 44 and 46, and a circular divider plate 48. Circular end plate 44 is separated from circular divider plate 48 by a cylindrical hub 50 to form a pulley groove 56. Circular end plate 44, hub 50, divider plate 48, cylindrical hub 52 and circular end plate are all bonded together to form a single integral pulley system 36. Power conductor 34 engages and rides in pulley groove 54 and takeup cable 38 engages and rides in pulley groove 56.

Pulley system 36 is pivotably mounted to a roller carriage assembly 58 by means of an axle 60. Roller carriage assembly 58 comprises a plate 62 to which axle 60 is attached. Also mounted to plate 62 are roller axles 64, 65, and 66 to which rollers 68, 69 and 70 are respectively pivotably mounted.

Attached to one side of fixed conveyor assembly 18 is a channel member 72 which may be the side channel of the conveyor. Channel member 72 comprises a main plate 74, side channels 76 and 78, at each end and perpendicular to main plate 74, and channel flanges 80 and 82 extending perpendicular from side channels 76 and 78, respectively toward one another (see FIG. 2). Each roller, 68, 69 and 70, has a roller groove 84 which engages one of the channel flanges 80 and 82. Thus, roller carriage assembly 58 can move in a substantially linear direction along channel member 72 as rollers 68, 69 and 70 roll in engagement with channel flanges 80 and 82.

Operation of this particular embodiment of the power conductor takeup means of the present invention may be described with reference to FIG. 1. In FIG. 1, the solid lines depict supporting assembly 14 and telescoping conveyor assembly 16 in a substantially extended condition with respect to fixed conveyor assembly 18. The broken lines in FIG. 1 depict support assembly 14 in a raised position with respect to the base 12 and show support assembly 14 and telescoping conveyor assembly 16 in a substantially retracted position with respect to fixed conveyor assembly.

As is illustrated in FIG. 1, when telescoping conveyor assembly 16 is in its fully retracted position (as depicted by the broken lines), pulley system 36 and roller carriage assembly 58 are positioned at the end of channel 72 closest to power hookup assembly 30. The positioning of roller carriage assembly 58 and pulley system 36 results from the interaction of power conductor 34 and takeup cable 38 as further described below.

As telescoping conveyor assembly 16 is extended outward from its fully retracted position as a result of hydraulic extension of expandable members 20 and 22, force is exerted on takeup cable 38 at point 40 wherein it is attached to telescoping conveyor assembly 16. This force causes tension in the takeup cable 38 which in turn causes force to be exerted against the circumference of pulley system 36. Since roller carriage assembly 58 is freely movable along channel member 72, movement of point 40 on telescoping conveyor assembly 16 tends to cause a movement of pulley system 36 and roller carriage assembly 58 by an increment of approximately one-half the distance of the movement of point 40. The one-half increment is in accordance with the principles of pulley mechanics for a single pulley system, i.e., the center of the pulley moves linearly by an increment of one-half the angular distance of travel of a point on the circumference all the pulley. Since point 33 where power conductor 34 attaches to power utilizing means 32 is a point on a substantially rigid member (i.e., telescoping conveyor assembly 16), point 33 moves the same distance as point 40. Consequently, as takeup cable 38 moves pulley system 36 and roller carriage assembly 58 along channel member 72, movement of point 33 will allow sufficient slack in power conductor 34 to prevent power conductor 34 from impeding the movement of pulley system 36 and roller carriage assembly 58. However, since the diameter of pulley groove 54 and 56 are the same, substantially all of the slack generated by the movement of point 33 is immediately taken up by the corresponding movement of the pulley system 36 and roller carriage assembly, 58, and thus, power conductor 34 is maintained in a substantially taut condition throughout the range of movement of telescoping conveyor assembly 16.

When telescoping conveyor assembly 16 is in its fully extended position (as depicted by solid lines in FIG. 1), the roller carriage assembly 58 and pulley system 36 will have been moved to the end of channe member 72 furthest from power hookup assembly 30 as a result of takeup cable 38 being pulled through pulley system 36.

If telescoping conveyor 16 is retracted from its extended position, movement of point 33 creates a tension in power conductor 34 which exerts corresponding force upon the circumference of pulley system 36. This force causes pulley system 36 and roller carriage assembly 58 to roll back along channel member 72. As when telescoping conveyor assembly 16 was extended, movement of point 33 causes a corresponding equal movement of point 40 which permits sufficient slack in takeup cable 38 to allow free movement of roller carriage assembly 58. However, because point 33 and point 40 move an equal distance, and because the circumference of pulley groove 54 and 56 are the same, movement of the telescoping conveyor assembly 16 causes power conductor 34 to move pulley system 36 and roller carriage assembly 58 so that takeup cable 38 is held in a substantially taut condition throughout the range of motion of conveyor assembly 16.

Thus, the interaction of power conductor 34 and takeup cable 38 when transversing pulley assembly 36 causes pulley assembly 36 and roller carriage assembly 58 to move laterally along channel member 72 proportionally as to the lateral movement of telescoping conveyor assembly 16 so that both power conductor 34 and takeup cable 38 are held in a substantially taut condition throughout the range of motion of telescoping conveyor system 16.

It should be expressly understood that because of the arrangement of the conveyors in this embodiment, utilization of a takeup cable 38 provides an economical and reliable means of positioning the pulley system 36 to takeup substantially all the slack in power conductor 34. However, a takeup cable is not the only means to perform this function. For example, a long helical spring could be utilized to spring bias and move pulley system 36 to hold power conductor 34 in a substantially taut condition throughout the range of movement of the telescoping conveyor assembly 16 without departing from the concept of this invention.

Claims

I claim:

1. In an apparatus comprising a relatively stationary first base member with a power source provided in association therewith and a second member movable with respect thereto and having a power utilization means provided in association therewith, an improved power conductor system adapted to conduct power from power source to said power utilization means comprising:

a rotatable pulley adapted to move in substantially linear direction substantially parallel to the direction of movement of the second member;

substantially lineal flexible power conductor means engaging and rotatably transversing the pulley, the power conductor means being attached at one of its ends to the power source and at its other end to the power utilization means; and

power conductor takeup means in engagement with the pulley adapted to move the pulley so that the power conductor is held in a substantially taut condition throughout the range of movement of the second member.

2. An improved power conductor system, as claimed in claim 1 wherein:

the takeup means comprises a takeup cable attached at one end to the first member and at its other end to the second member and position so as to engage and rotatably transverse the pulley; and

the power conductor and the takeup cable are positioned to cooperate with the pulley so that movement of the second member causes the pulley to move in such a manner as to hold the power conductor means and the takeup cable in a substantially taut condition throughout the range of movement of the second member.

3. An improved power conductor system, as claimed in claim 2, wherein the pulley is rotatably mounted on a carriage assembly which is mounted in engagement with the first member for translational movement with respect thereto.

4. An improved power conductor system, as claimed in claim 3, wherein the first member comprises a flanged channel member and wherein the carriage assembly has a plurality of rollers rotatably attached thereto, which rollers engage the flanged channel member and allow the carriage assembly to translate freely in engagement with the flanged channel member.

5. An improved power conductor system, as claimed in claim 3, wherein the pulley comprises a pulley wheel having a pair of pulley grooves formed thereon, with the power conductor engaging a first one of the grooves and the takeup cable engaging the other of the grooves.

6. In a telescopable belt conveyor system for conveying material comprising a first conveyor belt unit and a second conveyor belt unit, with the first and second conveyor belt units including a continuous conveyor belt loop, roller means for supporting the belt, a frame supporting the rollers, and power utilization means on the frame for causing the belt to move across the rollers, the first and second units being mounted so that the second conveyor belt unit is telescopably movable with respect to the first conveyor belt unit, and with the belt of the first conveyor belt unit being adapted to discharge its contents onto the belt of the second conveyor belt unit, an improved power conductor takeup system comprising:

a pulley movable in a substantially linear direction substantially parallel to the direction of movement of the second conveyor belt unit;

substantially flexible lineal power conductor means for conducting power from a power source mounted on the first unit to the power utilization means on the second unit;

the power conductor means being attached at one of its ends to the power source and at its other end to the power utilization means and being position to engage and rotatably transverse the pulley; and

takeup means in engagement with the pulley operably responsive to the movement of the second conveyor belt unit to move the pulley so that the power conductor means is held in a substantially taut condition throughout the range of movement of the second conveyor belt unit.

7. An improved power takeup system, as claimed in claim 6, wherein:

the takeup means comprises a takeup cable attached at one end to the first conveyor belt unit and at its other end to the second unit and positioned so that it engages and rotatably transverses the pulley; and

the power conductor and the takeup cable are positioned in cooperation with the pulley so that movement of the second unit causes the pulley to move in such a manner as to hold the power conductor means and the takeup cable in a substantially taut condition throughout the range of movement of the second unit.

8. An improved power conductor takeup system, as claimed in claim 7, wherein the pulley is rotatably mounted on a carriage assembly which is mounted in engagement with the first unit for translational movement with respect thereto.

9. An improved power conductor takeup system, as claimed in claim 8, wherein the first conveyor belt unit comprises a flanged channel member and wherein the carriage assembly has a plurality of rollers rotatably attached thereto, which rollers engage the flanged channel member and allow the carriage assembly to translate freely in engagement with the flanged channel member.

10. An improved power conductor takeup system, as claimed in claim 8, wherein the pulley comprises a pulley wheel having a pair of pulley grooves formed thereon, with a first one of the pulley grooves being engaged by the power conductor means and the other pulley groove being engaged by the takeup cable.