US2592644A - Hand truck - Google Patents

Description

HAND TRUCK 2 SHEETS-SHEET 1 Filed April 10, 1950 INVENTOR ATTORNEYS April 15, 1952 R. G. BARTLETT 2,592,644

HAND TRUCK Filed April lo, 1950 2 SHEETS-SHEET 2 INVENTOR Patented Apr. 15, 1952 UNITED STATES PATENT OFFICE HAND TRUCK Ralph G. Bartlett, Lakeland, Fla.

Application April 10, 1950, Serial No. 155,111

4 Claims.

This invention relates to hand trucks, and specifically hand trucks adapted for lifting and conveying stacks of boxes, for example boxes containing oranges, grapefruit or the like.

An important object of the invention is to provide a hand truck of this character including laterally movable arms with jaws formed at their outer ends adapted to grip the lowermost box of a stack of boxes, in a manner to secure the boxes to the truck, against accidental displacement.

Another important object of the invention is to provide means for adjusting the initial posi-- tions of the jaws within a certain range, to pick up boxes of various lengths.

Still another object of the invention is to provide laterally movable arms which may be readily moved and replaced by arms of greater or shorter lengths, depending on the size of the boxes to be lifted. A further object of the invention is to provide levers for operating the arms carrying the movable jaws, whereby the arms are moved to positions past dead center, locking the arms against movement under normal conditions.

With the foregoing and other objects in view which will appear as the description proceeds, the invention consists of certain novel details of construction and combinations of parts hereinafter more fully described and pointed out in the claims, it being understood that changes may be made in the construction and arrangement of parts without departing from the spirit of the invention as claimed.

Referring to the drawings:

Figure 1 is a bottom view of a hand truck, constructed in accordance with the invention.

Fig. 2 is a sectional view taken on line 2-2 of Fig. 1.

Fig. 3 is an enlarged view of the casing in which the operating levers and mechanism are encased, the cover plate of the casing having been removed.

Fig. 4 is a perspective view of one of the pivoted connecting plates between the actuating arms and movable operating plate.

Fig. 5 is a perspective view of one of the links connected with the actuating arms adjacent to the upper ends thereof.

Fig. 6 is a perspective view of one of the actuating arms.

Fig. 7 is a perspective view of one of the adjusting weights by means of which the initial positions of the clamping arms, are varied.

Fig. 8 is a perspective view of the cooperatin adjusting plate.

Fig. 9 is a perspective view of one of the bearing members;

Fig. 10 is a fragmental perspective view illustratin one of the bearings for the pivoted arms of the operating mechanism.

Referring to the drawings in detail, a hand truck is indicated generally by the reference character 5 to which the load clamping means, forming the subject matter of the present invention, is applied.

The load gripping means comprises a casing 6 formed with openings in the side walls thereof, which openings accommodate the sliding arms 1 that move therethrough, the arms 1 having forwardly extended arms 8 that have tapered jaws 3 extending inwardly therefrom, and adapted to move under the lowermost box of the load, in gripping and lifting the load.

The mechanism also includes the main m0vable plate it which is disposed substantially centrally of the casing, the plate l0 being provided with an elongated opening H with the nut l2 welded to the plate I!) adjacent to the upper end thereof, the .nut l2 extending rearwardly from the plate l0.

Laterally extended apertured ears !3 extend from the side edges of the plate [0, the ears l3 being slightly upwardly offset.

The sliding plate l4 fits over the movable plate l0 and is provided with the block 15, which is secured to the rear surface thereof, the block l5 having an opening it through which the pin ll extends, the pin ll being also connected with the forward end of the link IB that in turn connects with the forward end of the foot lever l9 that carries the pedal 20 at its free end.

The ends of the pin ll" which provides the pivot support for the foot lever I9, are mounted in openings formed in the bearing plates 2! that are secured to the bottom of the casing 6.

One wall of the casing 6 is provided with an opening through which the threaded shank 22 of the handle 23 extends, the threaded shank 22 operating within the opening of the nut !2, to move the main section or plate It. so that by rotating the handle 23, the threaded shank 22 may be rotated to move the adjusting plates to adjust them for their initial positions. The reference character 24 indicates a spacer that is positioned between the bottom and cover 25 of the casing, the spacer being positioned on the connecting bolt 26, used in connecting the cover with the main portion of the casing.

As clearly shown by Fig. 3 of the drawings, the sliding arms 1 are provided with elongated openin'gs 21that extend inwardly from the upper edges thereof, adjacent to the inner ends of the arms. These elongated openings accommodate the heads 28 formed on the forward ends of the actuating arms 29 which have pivotal connection with the sliding plate M, by means of the links 30, which links have bearings 3| at their outer ends, fitted in opening formed on the adjacent ends of the arms 29. These links 30 also have bearings 32 that fit within the openings 33 formed in the ears 34 extending laterally from the upper end of the sliding plate 14.

Mounted on each side of the main plate section It is a substantially triangular pivot plate 34, the plates 34' having rounded heads .35 that fit into the recesses 36' formed in the lower surfaces of the ears I3 of the plate I0, said recesses ac commodating the rounded heads for pivotal movement of the plates with respect to the plate It). Extending from the plates 34 are pins 35 that are disposed in the openings 36 formed in the laterally extended ears [3 and prevent the plates from becoming displaced When the bearing is loosened for removal of the arms 1.

These pivot plates also have openings 31 that accommodate the pins 33 extending from the arms 29, pivotally connecting the plates and arms. Extending from each plate 34, is a. threaded shank 39, the shanks 39 passing through openings 46] formed in the rear plate 42 of the casing, the openings in the rear plate of the casing, being slightly curved, a indicated by Fig. of the drawings, so that the pins 39 may move therethrough, when it is desired to elevate the arms 29 to remove them from the elongated openings or tions of the shanks 39, securing the bearing members 43 to the shanks. Finger pieces 44 extend from the threaded bearing members, whereby they may be readily rotated to position them. The plate 45 is Welded to the block I 5 and is disposed at right angles with respect to the upper and lower edges of the block l5, the edge of the plate 45 adjacent to the plate I4, being spaced from the plate a distance to accommodate the main plate section It which slides between the inner edge of the plate 45 and the plate l4.

Supporting wheels 46 are mounted on the axle 4'! of the truck whereby the truck is wheel-supported. Handles 48 provide means whereby the truck may be conveniently handled.

From the foregoing it will be seen that due to the construction shown and described, I have provided a hand truck having laterally sliding load gripping arms which are moved to their gripping positions, by means of the foot lever 19, operated by depressing the pedal 23. It might be stated that the movement of the foot lever I9 is slight, since it is only necessary to operate the arms 1 to move them a short distance to grip the load against which the truck is moved.

Due to the construction of the arms 29 and their adjusting means, the initial or main adjustment of the arms may be made by merely rotating the handle 23, which movement rotates the threaded shank 22 moving it through the threaded opening of the nut l2, which feeds the plates Ill and I4, to adjust them with respect to each other.

With this movement of the plates 10' and i4, it will be seen that the plates 34' and links 39 will be adjusted, moving the arms I to the desired position for actuation by the foot pedal.

Having thus described the invention, what is claimed is:

1. In a hand truck, a wheel supported frame, a housing mounted on the frame, a pair of sliding load supporting arms operating through openings in the side of the housing, a pair of pivoted actuating arms removably connected to the load supporting arms, operating means for said arms, said operating means embodying a pair of slidably connected inner and outer plates, ears extending from the plates, pivoted links connecting the ears of the outer plate with the actuating arms, pivoted plates connecting the ears of the inner sliding plate with the actuating. arms, means for adjust ing the sliding plates with respect to each other adjusting the initial positions of the actuating arms, and a foot lever connected with the inner sliding plate by means of which the actuating arms are operated, moving the load supporting arms into and out of their supporting positions.

2. In a hand truck, a wheel supported frame, a housing mounted on the frame, a pair of sliding load supporting arms operating through openings in the sides of the housing, and extending be-- yond the sides of the housing, a pair of pivoted actuating arms removably connected to the load supporting arms, operating means for said arms,

said operating means embodying a pair of slid-' ably connected inner and outer plates, ears extending from the plates, the ears of one plate having openings, pivoted plates having pins substantially smaller than said openings of the ears, operating in said openings, means for limiting pivotal movement of the pins in said openings supporting the plates, links connecting the actuating arms and the other plate, means for pivotally connecting the plates to said actuating arms, operating said actuating arms, and a pedal for effecting operation of said inner and outer plates.

3. In a hand truck, a wheel supported frame, a housing mounted on the frame, a pair of laterally sliding load gripping arms operating through openings in the sides of the housing, a pair of actuating arms pivotally mounted within the housing, removably connected to said load gripping arms, operating means for said arms enibodying a pair of sildably connected inner and outer plates, means for adjusting said inner and outer plates with respect to each other, ears extending laterally from one end of the outer plate, ears extending laterally from the inner plate at a point intermediate the ends thereof, pivoted plates connecting the actuating arms to the ears of the inner plate, links connecting the ears of the outer plate with one of the respective ends of the actuating arms, and a pedal for efiectingsliding movement of the plates and actuating arms operating said load gripping arms.

4. In a hand truck, a wheel supported f-rame a housing mounted on the frame, a pair of laterally slidable load lifting arms extending through the side walls of the housing, pivoted actuating arms removably connected with the load lifting arms, a pair of operating plates slidably mounted with respect to each other, mounted within the housing, a threaded nut secured to and extending from one of the plates, resting against oneend of the other plate, a threaded shank having an operating handle on one end thereof, operating in 2,692,644 5 6 said threaded nut adjusting the initial position REFERENCES CITED of the operating plate Within the housingrpivoted The following references are of record in the plates and links connecting the operating plates me of this patent: with the actuating arms, shanks extensibly secured to said pivoted plates connecting the piv- 5 UNITED STATES PATENTS oted plates within the housing, and a foot lever Number Name Date by means of which the operating plates are oper- 1,692,624 Byington Nov. 20, 1928 ated, swinging the actuating arms laterally oper- 2,024,267 Bartlett Dec. 17, 1935 ating the load lifting arms. 2,316,614 Pierce Apr. 13, 1943 10 2,367,752 Broome a- Jan. 23, 1945 RALPH G. BARTLET 2,500,047 smith Mar. 7, 1950

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