US2812972A - Grapple - Google Patents

Description

Nov. 12, 1957 R. s. ELBERTY GRAPPLE 3 Sheets-Sheet 1 Filed Feb. 28, 1955 Nov. 12, 1957 R. s. ELBERTY GRAPPLE 3 Sheets-Sheet 2 Filed Feb. 28, 1955 INVENTOR 6M 5. 5

ATTORNEYS Nov. 12, 1957 R. s. ELBERTY 2,812,972

GRAPPLE Filed Feb. 28, 1955 3 Sheets-Sheet 3 INVENTOR Q 7 BY i 25 M? ATTORNEYS United States Patent GRAPPLE Robert S. Elberty, Southington, C0nn., assignor to Jack Breslav, New Haven, Conn.

Application February 28, 1955, Serial No. 490,808

6 Claims. (Cl. 294-404)- particular application.

Grapples of this character are provided with gripping jaws suitably supported upon a frame or other mechanism, at least one of the jaws being movable with respect to the other, and levers are connected to the jaws or to the movable jaw of the frame so that when a lifting pull is exerted upon the levers, the jaws will be moved to closed position to grip the coil or other object which is to be lifted.

In the past such mechanisms have been relatively complex in construction or in some instances have been ineffective in that they would not properly grip the object which was to be lifted.

It is, of course, desirable to have the jaws movable directly toward each other or in a linear path. When the movement of the jaws or that of the movable jaw is effected by means of pivoted levers, it will be apparent that it is necessary to provide some means to convert the pivoted or rotary movement of the levers to linear movement of the jaw or jaws, and it is, of course, desirable that the structure be of as simple a construction and design as possible in order that it be economical in construction and that use of an unnecessary number of parts liable to breakage be avoided.

It is contemplated by the present invention to provide a lifting grapple or tongs with relatively few parts. As illustrated, the device comprises a frameor bar with which one of the gripping jaws is rigidly connected. To this bar member or box is pivoted a pair of lifting levers bent to bell-crank form, and the other jaw comprising an angular member is pivoted to one of the levers at a point adjacent its extremity and is pivoted to the other lever at an intermediate point of the latter, this second jaw member comprising a link member or being rigidly formed with a link member which is pivotally connected to the. two levers. This construction, as will be hereinafter explained, is such that the pivot points of the main levers with the frame and with the movable jaw member constitute the four vertices of a trapezoid, the diagonals of'which are formed by the link of the second jaw member and by the main frame. With this construction substantially linear movements ofthe jaw members are effected in asimple manner and with the use of relatively few parts. 4

One object of the invention is to provide a lifting grapple or tongs designed to grip an object to be transported from one place to another, which grapple will be of relatively simple construction and at the same time eflicient in use and satisfactory in operation.

A still further object of the invention is to provide a lifting grapple or tongs of the character described which 2,812,972 Patented Nov. 12, 1 957 will be of simple construction and which will at the same time positively and securely grip the object which is to be lifted and release the object when it is deposited upon a support.

A still further object of the invention is to provide a lifting grapple or tongs for transporting an object from one place to another wherein one of the gripping jaws is carried by the main frame of the device and a cooperating gripping jaw is carried by a link or lever pivoted to each of the two operating levers in such a manner that a linear motion of the movable jaws is effected, it being understood that the operating levers are pivoted to the main frame.

Still another object of the invention is the provision of a lifting grapple or tongs having a main frame to which are pivoted a pair of operating levers and cooperating movable jaw members, one of which is upon the frame, the other jaw being carried by a link member pivoted to each of the two operating levers, the construction being such that this link forms the diagonal of a trapezoid, the vertices of which are the pivots of the operating levers with the frame and with the link of the second jaw.

To these and other ends the invention consists in the novel features and combinations of parts to be hereinafter described and claimed.

In the accompanying drawings:

Fig. l is a side elevational view of a grapple embodying my invention with some parts being broken away, the mechanism being shown when the grapple has been lowered upon a coil preparatory to lifting the same;

Fig. 2 is a side elevational view of the grapple with the jaws shown in closed-position;

Fig. 3 is an end view of the grapple, the parts being shown in the same position as in Fig. 2;

Fig. 4 is a view similar to Fig. 1 but showing only one of the operating levers;

Fig. 5 is a view similar to Fig. 1 showing the other operating lever; and

Fig. 6 is a sectional view on line 6--6 of Fig. 1.

To illustrate a preferred embodiment of my invention, I have shown in the drawings a main supporting member comprising a bar or frame designated generally by the numeral 10. This member may consist of two plates 11 and 12 secured together in spaced relation, the plate 12 nearest the observer being broken away to show the interior construction. This supporting member 10 constitutes a bar having rigidly secured thereto and depending therefrom a gripping jaw 13. The jaw member 13 may be considered as the fixed jaw of the grapple although it will be understood that this is a relative term as either jaw may move relatively to the other.

Pivoted between the members 11 and 12 is a lever 14, this lever being pivoted to the bar 10 at its lower end, as shown at 15. This lever is of angle or bell-crank shape having a relatively short lower portion 16 adjacent the pivot at an angle to the portion 14 above the pivot.

Similarly a lever 17 is pivoted to the bar member between the members 11 and 12 at 18, this lever being shaped similarly to the lever 14 and comprises a short end 19 extending into the frame between the members 11 and 12 below its pivot. It will be seen, therefore, that while the lever 14 is pivoted at its end to the bar member and constitutes a lever of the second class, the lever 17 is pivoted intermediate its ends to the bar member and constitutes a lever of the first class with respect to this member.

To the upper ends of the levers 14 and 17 are pivoted links 21 and 22 respectively, these links being pivoted together at 23, at which point they are secured to an eye 24 by which the grapple may be lifted by derrick or other mechanism.

As shown more especially in Fig. 3, the lever 14 conelements, however, may be varied. For example, chains or cables may be used instead of the links 21 and 22.

The cooperating jaw is shown at 25 and, as illustrated, is pivoted to a second bar members constituted by a pair of bell cranks, each having a short end 27, the other part of which is comprised by a link 28. These bell cranks are in spaced parallel relation and are pivoted at one end to the short end 19 of the lever 17, as shown at 29, and at the other end are pivoted at 31) to the intermediate portion of the lever 14. As will be apparent the distance between the pivot points 18 and 29 is substantially equal to that between the pivotpoints 30 and 1S, and it will be seen that these pivot points form the vertices of a trapezoid. One diagonal of this trapezoid is constituted by the portions 28 of one of the bar members while the other is constituted by the bar member to which the levers 14 and 17 are pivoted.

It is desirable that some means be provided to lock the jaws of the grapple in open position so that it may be lowered upon a load to be lifted with the jaws in that position. To this end a member 31 is pivoted to the point 32, this being the pivot point between the members 17 and 22. This member 31 carries a laterally projecting pin 33 and also is provided with a weight 34 normally holding the member 31 in the position shown in Fig. 2. A cooperating locking mechanism 35 is provided in the main bar member 11 and, as this mechanism is substantially like that shown in the Breslav Patent No. 2,337,177, it need not be further described at this time.

When no load is being carried by the grapple, the jaws will be normally held in their open position by the locking mechanism 35 as shown in Figs. 1, 4 and 5. In this position the lever 14 and its connected link 21 will occupy the positions shown in Fig. 4, while the lever 17 and its associated link 2?. will occupy the position shown in Fig. 5. It will be seen that while the jaws are facing each other, they will be held in spaced position ready to receive an object to be gripped.

When the bar members are lowered upon such an object as the coil 36, shown in Fig. 1, for example, and a pull is exerted upon the eye 24, the levers 1d and 17 will be movedabout their pivots 15 and 18 respectively toward the position shown in Fig. 2 to effect a closing movement of the gripping jaws.

It will be apparent that as the lever 14 moves upwardly about the pivot 15, it will pull the link 28 to the right, as shown in the drawings, thus effecting a closing movement of the jaws. At the same time as the lever 17 is rotated about its pivot 18, it will exert a push upon the link 28 also moving the movable jaw in a closing direction. It will also be apparent that the pivot points 29 and 3'41 have very little vertical movement, their vertical movement being proportional to the distance of these points from the pivots 18 and 15 respectively and the angle through which the levers move and, as the angle is relatively small,.the distance will be relatively small. Therefore, a substantially linear movement is imparted to the jaw 25 and the pivotal movement of the levers 14 and 17 is converted into a substantially linear movement of the jaws.

Ehe upper ends of the levers 14 and 17 are bent inwardly toward each other, as shown at 14 and 17 so that they cross in the'closed position of the jaws, as shown in Fig. 2. This permits the links 21 and 22 to assume a lower position when the jaws are open, a

shown in Fig. 1, at an angle of from five to fifteen degrees with the horizontal.

It may be considered that the link 22 which is pivoted to lever 17 at the point 32 and the link 21 which is pivoted to the lever 14 at the point 32 form toggles with these levers, one member of each toggle being of bell-crank shape. Both of these levers are pivoted to the first bar member 10 and also to the second bar constituted by the members 27 and 28 which form a third member of bell-crank shape. The distance between the pivots 15 and 30 is substantially equal to that between the pivots 18 and 29 and this distance is substantially equal to that between the jaws in their full open position as shown in Fig. 1.

Also the arrangement is such that the line joining the pivots 15 and 30 is at an angle of about thirty degrees to the vertical upon one side of the pivot 30 when the jaws arein full closed position, as shown in Fig. 2, and at substantially the same angle upon the other side of the vertical when the jaws are in full open position, as shown in Fig. 1, and this is, of course, also true of the line joining the pivot points 18 and 29 so that the levers 14 and 17 travel through an angle of substantially sixty degrees from the full open to the full closed position.

It may be noted that the longer portion of one of the levers 14 or 17 may be omitted, if desired, together with the corresponding link 21 or 22 without affecting the operation of the device. For example, if the short portion 16 of the lever 14 is employed, as shown in dotted lines at 16 in Fig. 5, the remainder of the lever 14 and the link 21 may be omitted. In other words, that portion of the device shown in Fig. 5 together with the dotted line 16 will give satisfactory results, it only being necessary to connect the pivot points 15 and 30, and the grab may be operated with the lever 17 alone.

While I have shown and described a preferred embodiment of my invention, it will be understood that it is not to be limited to all of the details shown, but is capable of modification and variation within the spirit of the invention and within the scope of the claims.

What I claim is:

l.'In a grapple, a pair of bar members, each having a depending jaw, said jaws being disposed in opposed relation so as to cooperate to grip a load when given relative approaching movements, a pair of levers, each of said levers being pivoted directly to both said bars to effect movement of each thereof in the direction of its length when the levers are moved about their pivots, each of said levers being of bell-crank shape at their lower ends, one of said levers being pivoted at its lower end to one bar member and at its vertex to the second bar member, the other lever being pivoted at its vertex to said one bar member and at its lower end to said second bar member, the line joining the pivot points of the levers with one bar member crossing the line joining the pivot points of the levers with the other bar member and the lower arm of each of said levers normally standing at an angle of substantially thirty degrees on one side of a vertical line through the lever pivot when the jaws are closed.

2. In a grapple, a pair of bar members, each having a depending jaw, said jaws being disposed in opposed relation so as to cooperate to grip a load when given relative approaching movements, a pair of levers, each of said levers being pivoted directly to both said bars to effect movement of each thereof in the direction of its length when the levers are moved about their pivots, each of said levers being of bell-crank shape at their lower ends,

one of said levers being pivoted at its lower end to one bar member and at its vertex to the second bar member, the other lever being pivoted at its vertex to said one bar member and at its lower end to said second bar member, the line joining the pivot points of the levers with one bar member crossing the line joining the pivot points of the levers with the other bar member, the lower arm of each of said levers normally standing at an angle of substantially thirty degrees on one side of a vertical line through the lever pivot when the jaws are closed and at substantially the same angle on the other side of said vertical line when the jaws are fully opened.

3. A grapple comprising a frame member consisting of a pair of plates secured together in opposed relation, a lever of bell-crank shape pivoted at its lower end to said plates between the same, a second lever of bell-crank shape having its lower end extending between the plates and pivoted thereto at its vertex, a bar member between said plates pivoted at one end to the vertex of said first lever and pivoted adjacent its other end to the end of said second lever, a jaw member on the frame and depending therefrom, a cooperating jaw member depending from the said other end of said bar member and lying in opposed relation to said first jaw member, and means connected to said levers to move them about their pivots.

4. A grapple as in claim 3 in which the pivot points between said levers on the one hand and said frame member and bar member on the other hand constitute the vertices of a trapezoid, the upper side of which is shorter than the lower side when the jaw members are in full open position.

5. A grapple as in claim 4 wherein the line joining the pivot points of said levers with the bar member crosses the line joining the pivot points of said levers with the frame member and constitute the diagonals of said trapezoid.

6. A grapple as in claim 3 in which the pivot points between said levers on the one hand and said frame member and bar member on the other hand constitute the vertices of a trapezoid, the upper side of which is longer than the lower side when the jaws are in closed position.

References Cited in the file of this patent UNITED STATES PATENTS 509,920 Lindsay Dec. 5, 1893 1,406,704 Varicle' Feb. 14, 1922 1,758,526 Lewis May 13, 1930 2,020,823 Callahan Nov. 12, 1935 2,156,109 Brown Apr. 25, 1939 2,536,932 Heppenstall Jan. 2, 1951

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