US2804979A - Portable lifting apparatus - Google Patents

Description

P 3, 1957 H- D. LASSITER 2,M,979

PORTABLE LIF'TING APPARATUS Filed Nov. 19, 1954 3 Sheets-Sheet 1 8 FIG... 24 55 7/ do) 90 k 29 r .H. D. LASSITER PORTABLE LIFTING APPARATUS Sept. 3, 1957 Filed Nov. 19, 1954 3 Shee ts-Sheet 2 INVENTOR. D. 4485/ 7'5? Sept, 3, 11957 Filed Nov. 19, 1954 H. D. LASSITER PORTABLE LIFTING APPARATUS 3 Sheets-Sheet 3 United States Patent PORTABLE LIFTING APPARATUS Harmon D. Lassiter, Levelland, Tex.

Application November 19, 1954, Serial No. 470,181

Claims. (Cl. 212-59) This invention relates to hoists and more particularly to portable lifting devices.

It is an object of this invention to provide a portable lifting apparatus which is readily movable from place to place through relatively small openings, such as factory doors, garage doors, or the like, and which is simple in construction, easy to operate and of rugged construction serviceable with a minimum of maintenance over an extended period of time.

Another and still further object of the present invention is to provide a portable lift device wherein the height of the boom mast as well as the boom itself are selectively adjustable as to their length. "Yet another object of this invention is to provide an inexpensively constructed portable lift capable of hoisting considerable weight to the desired height, transport the hoisted material to another location, if desired, and which will find use in any place where considerable lifting or hoisting of materials is done.

Other objects and advantages will become apparent from a consideration of the following detailed description, forming the specification, and taken in conjunction with the accompanying drawings, in which:

Figure l is a side elevational view of the portable lifting apparatus embodying this invention;

Figure 2 is a top plan view;

Figure 3 is a fragmentary longitudinal, sectional view, taken substantially along line 3-3 of Figure 2;

Figure 4 is a rear view of the upper end of the mast or boom support taken substantially along line 4-4 of Figure l and looking in the direction of the arrows;

Figure 5 is a vertical cross sectional view taken substantially along line 55 of Figure 1;

Figure 6 is a side elevational view of the upper portion of the mast taken substantially along line 6-6 of Figure 4, and shown on a somewhat enlarged scale; and

Figure 7 is a diagrammatic view, in perspective, showing the manner in which the cable is connected about the pulleys for operating the boom.

With continued reference to the drawings, there is shown a lifting apparatus, generally indicated at 10, and which generally comprises a wheeled carrier 12, an upstanding mast 14, an adjustable boom 16, and a cable and pulley arrangement 20 for operating the boom.

The mast or standard 14 is carried by the carrier or truck 12. The boom 16 is carried by the mast 14 for movement in a vertical arcuate path, this movement being effected by the cable and pulley arrangement 20 in response to the action of rotatable force applied to the cable drum 21.

The carrier or truck 12 comprises a pair of oppositely disposed, spaced side frame members 22 and 24 which are of structural metal, of channel shape. The side frames 22 and 24 are maintained rigidly in their spaced apart relation by a spacer and reinforcing plate 26 which extends therebetween and secured to the parallel end edges of the respective lower legs 28 and 30 of the side frames and extends from one end to a point intermediate the ends 2,804,979 Patented Sept. 3, 1957 of the elongated, longitudinally extending side frames so as to be disposed, normally, in a horizontal plane.

Casters or wheels 32 carried adjacent opposite ends of each of the side frames 22 and 24 are arranged to swivel on a horizontal ball hearing as at 34, and thus support the carrier or truck 12. Each of the casters carry a brake or look 36 which may be manually rotated so as to contact the wheel and prevent its rotation and thereby render the carrier or truck stationary at a desired location.

An arm 38 is pivotally carried by the side frame 22 adjacent its end 21, from which the spacer and reinforcing plate 26 extends toward the opposite side frame end 23, by a pivot pin 40, which may be in the form of a bolt, passing through spaced parallel, laterally extending cars 42 through suitably formed aligned openings therein and through registering openings in the legs of the arm 38, which is of channel formation, so that the arm 38 will be carried by the carrier or truck for movement in a horizontal arcuate path to one side thereof.

Adjacent the end of the arm 38 remote from the end pivotally mounted on the carrier, there is dependingly carried a bracket 44 in which is rotatably mounted a caster 46. Also, the bight portion of the arm 38 is provided with an elongated, closed slot 48 which extends longitudinally thereof adjacent the end 37 remote from the end pivotally mounted on the carrier.

A similar, channel-shaped arm 50 is pivotally carried by the side frame member 22 at a location spaced from the point at which the arm 38 is pivoted and toward the free end 37 of the arm 38. This pivotal connection is defined by a pair of spaced, parallel, laterally projecting ears 52 having aligned apertures therethrough to receive a pivot pin 54, which may be in the form of an elongated bolt, therethrough and through registering openings in the outwardly extending flanges of the arm 50. Thus, the arm 50 is carried by the carrier or truck for movement in a horizontal arcuate path to one side thereof, this arcuate path of movement lying in the same horizontal plane as the path of movement of the arm 38 and intersecting the path of movement of the arm 38.

It will be noted that the bight portion extending between the outwardly projecting end flanges of the arm 50 is slightly wider than the corresponding portion of .the arm 38 so that the bight or web of the arm 38 will be telescopically received therein as the respective arms 38 and 50 are moved in their arcuate paths so as to extend substantially parallel to the side frame 22 upon which they are mounted.

With the arms 38 and St) in their closed or telescoping position, as shown in Figures 2 and 5, it will be possible to maintain these arms in their folded or telescoping relation by a bolt 56 passing through the slot 48 and received in a suitably threaded opening in the web portion of the side frame 22. In this latter connection, it should be noted that the leg 38 is of considerably greater length than that of the arm 50 so that the free end 37 of the arm 38 projects beyond the free end of the arm 5%.

An identical pair of arms 58 and 60 identical to the respective arms 38 and 50 are pivotally mounted on the opposite side frame members 24 at diametrically opposite locations therealong for movement in similar horizontal arcuate paths which intersect, and these arms are foldable into telescoping relation extending substantially parallel to the side frame 24.

Adjacent the free end of the arm 50, there is carried a depending bracket 62 which rotatably carries at its lower end a caster 64 so that both the caster 64 and the caster 46 will be in contact with the supporting surface upon which the casters or wheels 32 rest.

Similarly, the corresponding arms 58 and 60 are provided adjacent their free ends with freely rotatable casters 66 which also contact the supporting surface.

In their folded or telescoping position, the arms 58 and 60 may be secured to the side frame 24 by a bolt 68 passing through an elongated closed slot, similar to the slot 48, in the arm 58 adjacent its free end 59 and threadingly engaging the side frame member 24 in a suitably tapped opening through the web portion thereof.

With respect to the manner in which the arms 58 and 60 are mounted on the side frame 24, the side frame carries spaced parallel, laterally projecting ears, at spaced apart locations intermediate its ends, similar to the cars 42 and-52, and as indicated at 43 and 53, having respective pivot pins 41 and 55 arranged in the same manner as the corresponding pivot pins 40 and 54.

A carriage, generally indicated at 70, is. provided with a pair of oppositely disposed slide channels 72 and 74 with the opposite, parallel flanges thereof extending toward each other and telescopically received within the upper and lower legs 27, 28 and 29, 30 of the side frames 22 and 24 respectively so as to be slidable longitudinally thereof, with the side frames '22 and 24 defining guide rails for the slide channels 72 and 74 which are of lesser length than the guide rails 22 and 24 within which they are movable longitudinally in a rectilinear path. A base plate 76, of generally rectangular form, has its opposite longitudinal edges welded to the free longitudinal edges of the upper flanges of the slide channels 72 and 74 so as to extend therebetween and maintain the slide channels in their spaced relation and within the side frame members 22 and 24 which define guide rails for the carriage 70. The base plate 76 extends from the end of the slide channels adjacent the end of the truck remote from the outer ends 23 and 25 of the respective side frames 22 and 24, to a location intermediate the ends of the slide channels.

The lower end 78 of a tubular, hollow post 80 is rigidly secured to the upper'surface of the base plate 76 at its midpoint so that the post 80 is upstanding therefrom. The post 80 forms a part of the mast 14.

A hollow tubular post extension 82 has one end 84 thereof telescopically received in the open upper end'81 of the post 80.

The post extension has a plurality of longitudinally spaced, transversely aligned apertures 84 therethrough which are adapted to be placed in selective registry with one of the transversely aligned, longitudinally spaced apertures 86 provided through the post 80 so that the height of the mast 14 may be selectively adjusted and maintained in the selected position of adjustment by a stop pin 88 passing through the registering apertures. Or, the stop pin 88 may be inserted through the lowermost, transversely aligned ones of the apertures 86 so that the end 83 of the post extension 82 may' rest upon the shank of the stop pin, as shown in Figure 5.

Support braces 90 extend angularly downwardly and outwardly from the post 80 from a location intermediate its ends to be secured at their other ends to the upper surface of the base plate 76 as by being welded thereto at locations spaced from the base of the mast 14 to provide support for the mast for maintaining the-mast in its substantially vertical position with relation to the base plate 76.

The boom 16 comprises a hollow tubular body section 92 formed with a bifurcation at one end 93 and having its other end 94 open to receive telescopically therein one end 95 of a boom extension rod 96.

The other end 97 of the boom extension rod is flattened, and the rod is provided with longitudinally spaced bores therethrough from a location intermediate its ends to a location adjacent the end 95 which are adapted to be placed in selective registration with transversely aligned, longitudinally spaced apertures 98 whereby the length of the boom 16 may be. selectively adjusted and -maintained in the selectively adjusted position by a stop pin 99 being passed through the registering bore and apertures.

The boom 16 is carried at its bifurcated end upon the post extension 82 of the mast 14 intermediate the ends of the post extension for movement in a vertical arcuate path to one side thereof and through the open end or space between the frame members 22 and 24 of the truck or carrier 12. The open end of the truck or carrier being the end thereof remote from the end adjacent which the plate 26 extends between the frame members.

The post extension 82 carries a laterally projecting shelf 100 at a location above the pivotal connection 91 of the boom 16 upon the post extension. A motor 102 is supported on the shelf 100 and has its drive shaft provided with a pulley wheel 104 which drives a pulley wheel 106 through a drive belt 108. The pulley wheel 106 being mounted at one end of the shaft 110 of the cable drum 21. The shaft 110 which is rotatably carried in a U-shaped bracket 112 extending laterally from the post extension 82 at a location spaced above the motor 102. The shaft of the cable drum will be journaled in the opposite laterall extending legs of the bracket 112 so that'the cable drum is-rotatably mounted between the legs of the bracket, and this shaft has provided at its other end, remote from the end carrying the pulley wheel 106, with a ratchet wheel 114 which is to cooperate with a pawl 116 carried by the adjacent leg of the bracket 112 to prevent unwinding of the cable drum 21 as a load is beingliftedby the boom 16.

In order to have the boom 16 be moved in its vertical arcuate path, the cable and pulley arrangement 20 has beenprovided, and this arrangement includes the cable 118 woundaboutthe drum 21 and extending therefrom to be trained over the sheave 120 rotatably mounted in a sheave pulley bracket 122 carried at the top of the post extension 82 and extending longitudinally upwardly therefrom. The cable 118 is led from the sheave 120 to engagement with a sheave 124 rotatably mounted upon a pulley shaft 126 journaled in the bracket 122 adjacent its lower end and at a location spaced from the sheave 120 journaled upon an arbor 121 carried adjacent the upper end of the bracket 122. As the cable 118 extends about one side of the sheave 124 it is led about a pulley wheel or sheave 128 rotatably mounted on an arbor 130 rotatably journaled in the boom 16 at the flattened end portion-97 of the boom extension rod 96 so as to extend transversely therethrough and extend to either side thereof and may also carrya U-shaped guard 132 in surrounding engagement tothe pulley wheel 128 rotatably mounted thereon at one side of the flat portion 98 and to the other pulley wheel 134 also rotatably mounted on the arbor 130 and disposed at the opposite side of the flat portion 97.

The cable 118 after being trained about the pulley wheel 128 is led rearwardly to be trained about a sheave mounted on the pulley shaft 126 adjacent the end thereof remote from the end adjacent to which the sheave 124 is mounted, and thence the cable extends forwardly to be trained about the pulley wheel 134 and led upwardly and rearwardly therefrom to be anchored in a ring 136 carried by the bracket 122 at its uppermost end.

Thus, it Will be seen that upon operation of the motor 102 the cable drum 21 will be turned in one direction to move theboom 16 in its .arcuate path from the broken line-position shown in Figure 1 to the solid line position shown therein wherebya load may be lifted by the boom, the load being secured in the hook 138 dependingly carried adjacent the terminal end of the flattened end portion '97. Tolower the boom, it will be merely necessary to disengage the pawl and ratchet arrangement on the cabledrum 21 and cause the drum to rotate in the opposite direction. 'This may be done 'by use of a crank handle 140, which may be supported upon a hook 142 carried by the bracket 122.

Theapparatus''10 may be readily moved from one location to another by having it 'moved upon the supporting surface on the wheels or casters carried by the truck or carrier 12 to the desired location. Once at the desired location of use, the locks or brakes 36 are moved into relation with their associated casters or wheels 32 so as to prevent further rotation thereof and movement of the truck or carrier. The arms 38 and 59 may then be moved in their arcuate paths to one side of the truck, after loosening the bolt 56, so that these arms will extend in spaced parallel relation obliquely to the side frame of the truck 12 upon which they are carried to provide an out-rigger type of support or base for the apparatus. Similarly, the arms 58 and 60 will be moved in their arcuate paths away from their associated side frame member 24 to the positions shown in broken lines in Figure 2 where they will extend in substantially parallel, spaced relation to the other side of the truck and obliquely with respect thereto so as to define an out-rigger type base support for the lifting apparatus at the location of use.

The carriage 70 may then be moved longitudinally of the carrier or truck 12 and maintained in its selected position of adjustment longitudinally of the truck or carrier by stop pins 71 which will pass through registering openings in the upper flanges of the respective slide channels 72 and 74 and in the upper legs 27 and 29 of the respective side frames 22 and 24. This will enable the operator to so adjust the carriage, and the mast and boom carried thereon at a selected position longitudinally of the truck or carrier to afford wider versatility in the use of the lifting apparatus 10.

It should be noted that the post extension 82 may be disposed within the open end 81 of the post 80 to the desired degree by inserting the stop pin 88 in selected ones of the transversely aligned apertures 86 so that the lower end 553 of the post extension may rest thereupon and thereby selectively adjust the height of the mast 1-4. In this latter event, it will be of note that the transversely aligned, longitudinally spaced apertures 84 will provide means whereby the bifurcated end 93 of the boom may be selectively pivotally mounted in one of these transversely aligned apertures by the pivot pin 91. Thereby the boom 16 may be placed upon the mast 14 so as to have its axis disposed at selected locations longitudinally of the mast, whereby the height of the pivot 91 for the boom 16 may be raised or lowered with respect to the carriage 70.

Also, it should be noted that with the post extension 82 selectively adjusted as hereinbefore set forth wherein the lower end of the post extension rests upon the shank of the stop pin 88, the boom carried by the post extension may be moved to any position relative to the truck since it will move in a circular path about the center line of the post extension as an axis. This is true because the post extension is rotatable within the post 30, which in this case define, in effect, a socket for the post extension.

In the event that the boom is to be used to one side or the other of the truck or carrier 12, it may be desirable to move the carriage 70 longitudinally of the truck so as to better distribute the weight load to be lifcd as well as effecting the better balance of the entire apparatus.

From the foregoing, it will be apparent that there has been provided in a portable lifting apparatus, a wheeled truck 12 which includes spaced side frame members 22 and 24 of channel form which define guide rails, a carriage 70 slidably mounted in the guide rails defined by the frame members for movement longitudinally of the truck, an upstanding boom mast carried by the carriage, a boom mounted on the mast for movement in a vertical arcuate path, and means including the pulley and cable arrangement which includes the cable drum 21 and hte motor 102 for imparting rotation to the drum so that this means carried by the mast 14 is operatively connected to the boom 16 for moving the boom in its arcuate path.

There is also provided means in the form of stop pins 71 which enter through registering openings in the guide rails or side frame members 22 and 24 and the corresponding slide channels 72 and 74 for securing the carriage in a selected position longitudinally of the truck 12.

While there are shown and described the preferred embodiment of the invention, it is to be understood that the invention is susceptible to change and modification within the practicability of the invention and therefore should be limited only by the scope of the claims appended hereto.

What is clairned is:

1. In a portable lifting apparatus, a wheeled truck including spaced side frame members of channel form to define guide rails, a carriage slidably mounted in said guide rails for movement longitudinally of said truck, an upstanding boom mast carried by said carriage, a boom mounted on said mast for movement in a vertical arcuate path, and means carried by said mast and operatively connected to said boom for moving the boom in its arcuate path, a pair of arms carried at one end by each of said side frame members for movement about longitudinally spaced axes in horizontal arcuate paths from a position wherein said arms are substantially parallel to their associated frame member to a position wherein the arms are in spaced substantially parallel relation and disposed obliquely with respect to their associated frame members, and a caster carried by each one of said arms at the other end thereof.

2. In a portable lifting apparatus, a wheeled truck including spaced side frame members of channel form to define guide rails, a carriage slidably mounted in said guide rails for movement longitudinally of said truck, an upstanding boom mast carried by said carriage, a boom mounted on said mast for movement in a vertical arcuate path, and means carried by said mast and operatively connected to said boom for moving the boom in its arcuate path, a pair of arms carried at one end by each of said side frame members for movement about longitudinally spaced aXes in horizontal arcuate paths from a position wherein said arms are substantially parallel to their associated frame member to a position wherein the arms are in spaced substantially parallel relation and disposed obliquely with respect to their associated frame members, and a caster carried by each one of said arms at the other end thereof, said mast including a hollow post and a post extension received therein, means for securing said extension in a selected position within said post to selectively adjust the height of said mast.

3. In a portable lifting apparatus, a wheeled truck including spaced side frame members of channel form to define guide rails, a carriage slidably mounted in said guide rails for movement longitudinally of said truck, an upstanding boom mast carried by said carriage, a boom mounted on said mast for movement in a vertical arcuate path, and means carried by said mast and operatively connected to said boom for moving the boom in its arcuate path, a pair of arms carried at one end by each of said side frame members for movement about longitudinally spaced axes in horizontal arcuate paths from a position wherein said arms are substantially parallel to their associated frame member to a position wherein the arms are in spaced substantially parallel relation and disposed obliquely with respect to their associated frame members, and a caster carried by each one of said arms at the other end thereof, said mast including a hollow post and a post extension received therein, means for securing said extension in a selected position within said post to selectively adjust the height of the mast, and means for selectively and pivotally mounting said boom on said post extension at one of a plurality of spaced apart locations longitudinally thereof.

4. In a portable lifting apparatus, a wheeled truck including spaced elongated side frame members, a pair of arms carried at one end by each of said side framemembers for movement about longitudinally spaced axes in horizontal arcuate paths from a position wherein said arms are substantially parallel to their associated frame member to a position wherein the arms are in spaced substantially parallel relation and disposed obliquely with respect to their associated frame members, an upstanding boom mast carried by said truck, a boom mounted on said mast for movement in a vertical arcuate path, and means carried by said mast and operatively connected to said boom for moving the boom in its arcuate path.

5. In a portable lifting apparatus, a wheeled truck including spaced elongated side frame members, a pair of arms carried atone end by each of said side frame members for movement about-longitudinally spaced axes in horizontal arcuate paths from a position wherein said arms are substantially parallel to their associated frame member to a position wherein the arms are in spaced substantially parallel relation and disposed obliquely with respectto their associated frame members, an upstanding boom mast carried by said truck, a boom mounted on said mast for movement in a vertical arcuate path, and means carried by said mast and operatively connected to said boom formoving the boom in its arcuate path, and means for securing each pair of arms to the corresponding frame member in their position substantially-parallel to the corresponding frame member.

References Cited in the file of this patent UNITED STATES PATENTS 1,284,277 Ewig et a1. Nov. 12, 1918 2,082,017 McClain June 1, 1937 2,292,870 Dixon Aug. 11, 1942 2,320,601 Howell June 1, 1943 2,365,167 Billings a Dec. 19, 1944 2,496,401 McKinney Feb. 7, 1950 2,699,875 Stratton Jan. 18, 1955 2,706,120 Stratton Apr. 12, 1955 FOREIGN PATENTS 535,357 Great Britain Apr. 7, 1941

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