Floor Hoist

Abstract

A low profile portable hydraulic hoist for handling heavy structures in cramped quarters. It includes a castered frame, a pivoted arm mounted on the frame and an adjustable head means mounted on the end of the arm for holding the structure to be moved. Hydraulic cylinders are used to elevate the arm and tilt the head, which may also be manually rotated.

Description

STATEMENT OF GOVERNMENT INTEREST

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to lifting equipment and more particularly to a hydraulic hoist for manipulating heavy objects in cramped quarters.

2. Description of the Prior Art

The lifting and removal of heavy equipment has always involved many problems due primarily to the cramped space in which the devices needed for handling purposes must be employed. Most of the hoists which have been developed are too bulky and are not sufficiently adaptable to remove such heavy structures. The present invention, however, being of low profile and of high adaptability, may be used in most situations where other equipment can not be employed.

SUMMARY OF THE INVENTION

Briefly, the present invention involves a powerful floor hoist useful in heavy equipment shops, garages, ordnance shops, etc. The device is low profiled and includes a castered frame, a load raising arm pivotally attached to the frame and an adjustable adapter connected to the arm for engaging and hoisting heavy objects such as truck transmissions or the like. Hydraulic cylinders are used to elevate or lower the arm and to tilt the adapter, which may also be manually rotated.

STATEMENT OF THE OBJECTS OF THE INVENTION

Accordingly, it is an object of the present invention to provide a hoist of high reliability, low cost and great adaptability.

Another object of the present invention is to provide a hoist of very low profile to permit utilization in confined quarters.

Still another object is to provide a hoist which will allow safe removal of truck differentials without damage thereto.

Another object is to provide a hoist in which the tilt and hoist mechanisms may be independently operated.

Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings wherein:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of the hoist in a partially raised position.

FIG. 2 is a top plan view of the hoist of FIG. 1.

FIG. 3 is an enlarged front view of the index plate but with a portion broken away.

FIG. 4 is an enlarged side view showing the details of the adjustable structure used engaging a heavy object.

FIG. 5 is an enlarged perspective view similar to FIG. 3, but with a portion broken away.

DESCRIPTION OF THE PREFERRED EMBODIMENT

This invention comprises a hydraulic floor hoist employed in garages, ordnance shops and the like for manipulating heavy machinery, vehicle transmissions, projectiles and similar structures. It is of low profile to facilitate movement under vehicles and may be used in very cramped quarters. The load carried may be held on adjustable forks on a load engaging fixture which is located on the tip of an elongate arm. Hydraulic cylinders are used to elevate the arm and tilt the fixture.

Referring more particularly to the drawings, the invention comprises an elongated frame 10 constructed preferably of a pair of spaced tubular members 12 which are substantially in parallel relationship. A tubular cross member 14 is welded or otherwise secured to one end 16 of members 12 and an upwardly and rearwardly projecting support bracket 18 is mounted on the cross member 14 between members 12. A flat support plate 20 is mounted to the undersurfaces of members 12 contiguous to cross member 14. Both members 12 have end plates 22 and 24 secured thereto on which are mounted swivel casters 26.

An elongate hoist arm 28 is pivotally mounted at its lower end to the lower end of support bracket 18 welded to cross member 14. The opposite end of arm 28 is pivotally connected to a tiltable and rotatable head assembly by pin 33 received in spaced bosses 34; the bosses in turn are welded to the rear face of tilt plate 35.

A hydraulic tilt cylinder 30 is mounted on the end of arm 28 and contains a piston rod 38 which latter extends axially of the cylinder. The outer end of the piston rod bears a roller bar 40 (FIG. 4) supporting two rollers 42. The rollers are aligned with and are adapted to move along a pair of spaced parallel curved tracks 44 secured to the rear face of tilt plate 35.

The means of operating the hydraulic mechanism for piston rod 38 includes a tilt pump assembly and oil reservoir 67 (FIG. 2) mounted on support plate 20 and operated by handle 69. The pump 67 supplies suitable hydraulic pressure through line 70 to force the piston rod 38 out of the cylinder 30. Such movement causes the rollers 42 to move along spaced tilt tracks 44 which pivots the tilt plate 35 about the pivot pin 33.

A face plate 49 may be secured to the forward face of tilt plate 35 by a series of bolts and nuts 46 and 48, face plate 49 serving as a mounting base for a rotatable index plate 60 centrally journalled thereon at hub portion 56. Between face plate 49 and index plate 60 are a series of peripherally located rollers 50 suitably mounted on the front face of face plate 49 by means of roller pins 52 received in spaced cheeks 54.

The index plate 60 may be in the form of a round flat disc as shown and is preferably provided with a series of spaced peripherally located holes 66 by which the angle shaped fork members 62 may be adjustably mounted utilizing the tie bolts 64.

Index plate 60 is mounted on hub 56 and is caused to rotate about such hub by a simple screw and nut mechanism. Such an arrangement is shown in detail in FIG. 3 where a portion of the index plate 60 is shown broken away to expose a screw 86 supported on face plate 49 by lug 88 which is pivotally mounted on the front surface of face plate 49. The outer end of the screw is provided with a hexagonal head 90 to receive a socket wrench or crank by which the screw may be rotated. Collar 92 retains the parts in juxtaposition.

The inner end of screw 86 is threaded through a nut 94 which is pivotally supported on the inside face of index plate 60. Thus it will be seen that rotation of screw 86 rotates index plate 60 about its central pivot 56.

A hoist cylinder 68 may be pivotally secured at one end to the top of support bracket 18 by journal 70 and pin 71. The hoist piston rod 72 is pivotally connected by pin 74 to cheek brackets 76 welded or otherwise secured to the top portion of the hoist arm 28. Hoist cylinder 68 is employed to elevate and lower the hoist arm 28 and thus similarly move any attached structure including index plate 60 with the connected fork members 62.

To actuate hoist cylinder 68, a hoist pump assembly and associated reservoir 78 is mounted on support plate 20 and is operated by a handle 80, thereby providing hydraulic pressure to hoist cylinder 68 through lines 82 and 84 to actuate piston rod 72 into or out of cylinder 68. Such movement will effect the required up or down movement of hoist arm 28. Both pump assemblies 67 and 78 include a hydraulic valve 79 permitting return of the oil to the reservoir.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

Claims

I claim:

1. A low profile hydraulic hoist assembly capable of being positioned in an area having cramped space restrictions comprising:

an elongated and wheeled frame adapted to be easily positioned in said cramped area;

a lifting arm pivotally mounted at the inner end to said framework and with the outer end adapted to extend into an area above said frame;

hydraulic means for raising the lifting arm and causing the outer end thereof to elevate;

a load engaging head assembly pivotally mounted to the outer end of said lifting arm;

hydraulic means for effecting tilt movement to said head assembly, said means mounted on the outer end of said lifting arm and adapted to extend coaxially with the longitudinal axis of said lifting arm; and

means for allowing rotation of a portion of said head assembly about a central axis.

2. The hoist as defined in claim 1 wherein:

said means for effecting tilt movement of the head includes a tilt cylinder mounted axially on the outer end of the lifting arm and a tilt pump assembly to provide pressure to said cylinder,

said cylinder containing a piston rod adapted to extend axially out of the cylinder, and

means pivotally connecting the outer end of said tilt cylinder to said load engaging head

whereupon movement of said piston rod will cause a tilting motion to be imparted to the head with respect to the axis of said lifting arm and tilt cylinder.

3. The hoist as defined in claim 2 wherein:

said means pivotally connecting the outer end of said tilt cylinder to the head includes

a bracket and pin arrangement attaching the outer end of said tilt cylinder to the load engaging head in a movable relationship,

a pair of rollers attached to the outer end of the cylinder piston rod, and

a pair of curved parallel tracks secured to the load engaging head, said rollers adapted to move on the tracks when the piston rod to which they are attached moves in and out of said tilt cylinder,

thus causing said tilting motion to be imparted to the head.

4. The hoist as defined in claim 1 wherein the hydraulic means for pivoting the lifting arm includes:

a hoist cylinder pivotally mounted at one end to the frame,

a hoist cylinder piston rod pivotally connected to the lifting arm and,

hoist cylinder pump means to provide pressure to said hoist cylinder

whereupon movement of the hoist cylinder piston rod will provide vertical movement to said lifting arm.

5. The hoist as defined in claim 3 wherein the rotatable load engaging head comprises:

a tilt plate to which said pair of curved and parallel tracks are secured and which cooperates with said rollers mounted on the tilt cylinder piston rod to provide tilting movement to the head assembly;

a face plate mounted upon said tilt plate for tilting movement therewith;

an index plate rotatably supported on said face plate having a series of spaced and peripherally located apertures therein;

means interconnecting said face plate and said index plate, said means being adjustable to allow rotation therebetween about their common central axis; and

angle shaped supporting members adjustably mounted in the apertures.

6. The hoist as defined in claim 5 wherein said means interconnecting said face plate and said index plate includes a nut and bolt arrangement in which the nut is attached to said index plate and the bolt is threadedly engaged with said nut, the bolt being secured to said face plate;

thus upon rotation of the bolt suitable rotation is provided to the index plate.

7. The hoist as defined in claim 3 wherein said angle shaped supporting members are in the form of forks.