US2576016A - Lifting jack - Google Patents

Description

Nov. 20, 1951 M. B. JANUSZ LIFTING JACK Filed April 4, 1947 2 SHEETS-SHEET l affowbe a Nov. 20, 1951 M. B JANLIJSZ LIFTING JACK Filed April 4, 1947 2 SHEETS-SHEET 2 Patented Nov. 20, 1951 LIFTING JACK Mitchell B. Janusz, Chicago, Ill.,assignorto Sears, Roebuck and 00., Chicago, 111., a corporation of New York Application April 4, 1947, Serial N0. 141,005

2 Claims.

My invention relates to ,jacks for lifting heavy articles and is especially designed for lifting large, heavy and awkward articles of furniture, a special application being in connection with the lifting of merchandise display tables andcabinets having an undercut base. Such articles are very awkward, heavy and inconvenient to lift, espe' cially when loaded with merchandise.

Anobject of my invention is to provide a jack having an elongated lifting member for engaging a lower surface of a heavy and bulky object and which is so designed that, by a relatively slight manual effort, a person may conveniently raise such object from the floor.

Still another object is to provide a device of the character referred to which is readily portable, so that it may be conveniently moved by itself or when supporting a heavy article.

Still another object of the invention is to provide a device of the character referred to which may be made inexpensively from a relatively small number of simple parts and which will be rugged and durable.

Another object is to provide a lifting jack wherein a relatively slight manual force may be transmitted to a plurality of lifting means at spaced points on an extended lifting member, so that a large and bulky object may be raised by means of such member and whereby lifting force is distributed over an extended area.

Various other objects and advantages may suggest themselves to those skilled in the art as the description proceeds.

Referring now to the drawings forming a part of this specification:

Fig. 1 is a perspective view of a jack embodying my invention;

Fig. 2 is a side elevational view showing two of such jacks applied to the lifting of a cabinet having an undercut base;

Fig. 3 is an enlarged fragmentary sectional view taken substantially along the line 33 of Fig. 1, with the addition of a portion of a cabinet to which the jack is applied;

Fig. 4 is a fragmentary elevational view showing one end of a jack embodying my invention, in raised position; and

Fig. 5 is an enlarged fragmentary sectional view taken substantially along the line 5--5 of Fig. 1.

In the preferred embodiment shown in the drawings, a jack embodying my invention comprises a pair of elongated force distributing and weight distributing members which, in the preferred embodiment shown comprise angle bars 2 l0 and If). These angle bars are arranged in nested relation and are slideably secured together :by suitable i'neans, such as a pair of bolts and nuts 12, I2, fixed to the bar H! and extending through slots 13 in the bar I0. The bar It "has attached thereto suitable casters [5, whereby the jack may be conveniently transported on a floor.

Pivotally secured to the bar 10' as by means of a pin or stud H is an elongated upstanding lever having a handle portion 2|. Pivotallyattached tothe lever'2-0 is a pair of links '25, 25. Each of the 25 bifurcatedateach end as at 26, 26, to accommodate a pivot pin. Pivotally connected to the outer extremity of each of the links 25 is a connecting rod 28, 28. Each of the connecting rods 28 is bent adjacent its lower extremity to form a right angled crank portion 29 which extends through an aperture in the angle bar I0, this crank portion 29 having secured thereto, as by means of a pin 35, a lifting cam 32. The cams 32, 32 lie on the horizontal flange of bar 10', whereby the weight resting on the cams when the jack is loaded, is distributed. (See Fig. 3.)

Arranged on the lever 20 is a sleeve 50 which may be frictionally retained by a leaf spring (not seen). At opposite ends of the sleeve are provided downwardly extending rectangular hooks 52, 52, adapted to engage a marginal ledge of a table, cabinet or show case. As seen in Fig. 2, the lower hook 52 is at a convenient height for a cabinet or table; the upper hook may be used on a show case by slipping the sleeve off the lever and turning it around, so that hook 52' is on the same side as the case. By so engaging the sleeve on the article to be raised, the jack is locked in elevated position, since, obviously, restraining the lever against pivotal movement will effectively prevent lowering of the cams.

The cams 32 are so positioned on the rods 29 that when the lever 25 is in an extreme angular position, as indicated by the dotted lines 35, the cams 32 will be at or near a horizontal position so that the angle bar I0 will be in its lowermost position. The jack may be rolled on its casters to a point where the horizontal flange of the angle bar I0 is brought under a surface of the article to be raised. This is well illustrated in Figs. 2 and 3 Where the jack is shown in lifting relation to a cabinet C having an undercut base B. The lever 25 is then manually rotated about its pivot l1, the force being transmitted through the links 25 and connectin rods 28 to the cams 32. Rotation of these cams 32 applies a lifting force to the angle bar ID, the force being distributed throughout the length of this bar and thus the cabinet or other object is raised off the ground. The distance through which the object is raised is quite sufficient to permit moving the object to any desired position, especially when a pair of jacks is applied to opposite sides of the object, as shown in Fig. 2. Obviously, the cams 32 and slots l3 may be sodesigned as-to provideanyamount of life desired. For the purpose herein shown a relatively slight distance is sufficient.

Obviously, the lifted article may be lowered by merely releasing the lever and shiftingitabout its pivot H, from its vertical position to one of the angular positions shown dotted in Fig.1 or i v Fig. 4. J V

Various changes coming within the spirit of my invention may suggest themselves to those skilled in the art, and hence I do not wish to be limited to the specific form shown or uses mentioned, except to the extent indicated in the appended claims:

a e I claim:

engaging an article to be lifted, whereby the jack may be secured in elevated position. I

2. A jack comprising a pair of elongated angular rails secured in nested relation to permit vertical movement therebetween a pair of spaced cams disposed between said rails for effecting vertical movement of the upper rail, means for actuating-cachet said cams comprising an upstanding rod secured to each of them, an upstanding lever pivoted approximately midway between said cams and substantially on the line joining the axes of said earns, a pair of links connecting said lever with said rods at a level elevated from said rails, said lever being normally operable from a standing position.

I MITCHELL B. JANUSZ.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,056,729 Aspy Mar. 18, 1913 1,196,638 Atherton Aug. 29, 1916 1,827,692 Vik Oct. 13, 1931 FOREIGN PATENTS Number Country Date 574,923 France July 21, 1924 575,066 Germany Aug. 8, 1931

Images