US1709746A - Jack - Google Patents

Description

April 16, 1929.

F. H. SC/HWERIN JACK Filed March 1928 2 Sheets-Sneak April 16, 1929. 1 H. SCHWERIN JACK , 1928 2 Sheets-Sheet Filed March 2 I INVENTOR A 776 ANE Patented Apr. 16, 1929.

' UNITED STA TES PATENT OFFICE.

FRANK H. SCHWERIN, or BELLEVUE, P'ENNsY VANIA, ASSIGNOR To THE DUFF- NORTON MANUFACTURING COMPANY, or PITTSBURGH, PENNSYLVANIA, A COR- PORATION OF PENNSYLVANIA.

JACK.

Application filed March 2,1928. Serial No. 258,495.

The invention relates to jacks and more particularly to lifting jacks.

The general object of the, invention is to provide a jack of the geared toggle type which is very simple in construction, strong and efficient, and the elements and arrangen'ient of which are such as very greatly to facilitate the manufacture and cheapen the cost of production. I

In the accompanying drawings forming part hereof:

Fig. 1 is a side elevation of the improved toggle jack in a partly raised condition, with a portion of the screw shaft broken out, and showing also a long extension handle connected with the jack by means of the preferred form of the separable flexible operating connection, intermediate portions of the handle, constituting most of its length, being broken out;

' Fig. 2 is sectional view of the part on the inner end of the separable handle, shown in a position in relation to Fig. 1 in which it can 1 be entered into engagement with the jack; Fig. 3 is an end view of the head on the actuating element of the jack illustrated in Fig. 1' I F ig. 4= is a fragmentary view with one part in section and another part inelevation, 11- lustrating another .form of separable opersting connection between the jack and han- Fig. 5 is a cross-section on the line 55 of Fi 4 Figjfi is a sectional view of the ack proper taken in the central vertical planeof the axis of the screw, which itself is in elevation, full and broken lines being used to show different positions of the jack; and

tion through the jack.

' The jack has a suitable base 2 provided with spaced portions 3. These portions are pierced with alined openings for two pivots 4 and 5, the ends of which are upset outside of the portions 3, and it will be noted that the openings are so located that the axes of these pivots do not lie in a horizontal plane but are-at somewhat different levels.

Two pairs of lower arm elements 6 and-7,

forming two double arms, are swung on the pivots 4: and 5, the members of each double am being separated by spacers 10.

Two pairs of upper arm elements 8 and 9,

Fig. 7 is a central vertical transverse secalso forming two double arms, are pivoted to the arms 6 and 7 on trunnions 11 and 12 proposed between the upper'ends of the pairs of arm elements 8 and 9.

The actuating means of the tick preferably comprises a screw shaft 21, which is preferably a right and left hand screw, engaging the members 13 and 14 formed as nuts.

The arms 6 arid 8 form a toggle, and the arms 7 and 9 form another toggle, the two toggles flexing in opposite directions. It

will be understood that corresponding elements of the double arms 6 and 7 lie in the same vertical planes, and similarly the elements of the double arms 8 and 9.

The lower ends of the arm elements 6 and I 7 are formed with integral toothed gear or segment formations 22, inter-gearing the toggles at the bottom. The upper ends of the armelements 8 and 9 have the same formations 22 inter-gearing the toggles at the top.

An important feature of the jack thus far described is that all the arms, and indeed all.

eight of the arm elements 6, 7, 8 and 9 are duplicate and interchangeable, being of the same length, having the same pivot openings, and in particular having the same number of teeth 22 on one end of each, in precisely the same position on each link. This involves setting the pivots 4 and 5, or the centers of these pivots, at different levels on the base, as has been mentioned previously, in order that the teeth may intermesh. The centers 11 and '12 lie at similarly different relative levels, and the centers 15 and 16 connect the arms '8 and 9 with the upper member 17 also at the same relative difier'ence of level. This last does not necessitate setting the top at an inclination,since, by appro priate relation between'the top rest 18 and the pivot openings in the-side portions 19, the top rest can be leveled.

Heretofore, in geared toggle or lazy tong jacks, it has been necessary to make different arm elements in order that the teeth might mesh, and these elements have not been interchangeable. Thepresent jack is more easily produced, at considerably less cost indies, and with much greater facility in assembling, since any element will go in any position. Also, in caseof repair, an arm element from a single stock will replace any arm element of the jack. I

The inclination of the actuatingshaft 21 resultingfrom the difference in level. of the middle pivots has a further advantage in reducing the angle between this shaftand an I operating handle in the operation of the jack.

' Coming now to the operating handle, it

- will be seen that one end of therotary actuatfrom the narrow or shank portion of the part 23 when the axes of the parts are approximately at 90, or thereabouts, that is to say, at a decided angle, but when the handle is straightened more or less in line with the rotary actuating element of the jack, the pins 27 in engagement with the grooves 24 retain:

the handle against'coming off sideways and against being pulled off endwise. Rotation of the handle will thus raise and lower the jack, and the handle can also be used to push the Jack into place and to draw it out after the operation is over. The longitudinal convexity of the faces of the head 23 enables the ,f handle to be held at a range of inclinations and still to operate the member 21.

The handle may be composed of two ections 30 and 31 that can be taken apart, the sections being connected by a sleeve 28 fixed to one section and having slots to be engaged.

by pins 29 on the other section. The section parts 23 and 26, or 23- and 26*, might be reversed with respect to the jack and handle.

I claim:

1. A toggle jaclg comprisinga base, a top, eight arm elements forming two toggles between the base and' the top, and means for actuating'the toggles, oneend of each arm element having an integral toothed gear for mat-ion, and all eight arm elements being duplicate and interchangeable.

2. A toggle jack comprising a base, an upper member, two toggles, pivots connecting the arms of the respective toggles with each other, other pivots connectingthe lower toggle arms with the base and the upper toggle arms with the upper member, said arms having integral meshing gear tooth formations, at the top and ,bottom, and means, for'a'ctuating'the toggles, all corresponding pivots of the two toggles being. at different levels, and all of the arms being duplicate and interchangeable.

3. A toggle jack com rising a base, an up per member, two togg es, pivots connecting the arms of the respective toggles with each other, other pivots connecting the lower toggle arms with the base and the upper toggle arms with the upper member, said toggles having integral moshing gear tooth formations at the top and bottom, all correspondingivots of the two toggles being at different levels, and all of the arms being duplicate and interchangeable, and an inclined screw shaft connecting the-middle pivots.

FRANK H. SCHWERIN.

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