US2745695A - Lifting tongs locking unit - Google Patents

Description

May 15, 1956 F. PEYER 2,745,695

LIFTING TONGS LOCKING UNIT Filed March 9, 1951 3 Sheets-Sheet 1 1N VENTOR FQ'rlZIZZ: lqye May 15, 1956 F. PEYER 2,745,695

LIFTING TONGS LOCKING UNIT Filed March 9, 1951 3 Sheets-Sheet 2 INVENTOR flank Peyer.

May is, 1956 F. PEYER 2,745,695

LIFTING TONGS LOCKING UNIT Filed March 9, 1951 3 Sheets-Sheet 5 INVENTOR Frail}: .Peyer BY f/W? United States Patent LIFTIN G TONGS LOCKING UNIT Frank Peyer, Bethlehem, Pa., assignor to Bethlehem Steel Company, a corporation of Pennsylvania Application March 9, 1951, Serial No. 214,749

13 Claims. (Cl. 294-118) This invention relates to tongs of the type adapted for lifting heavy articles such as ingots, slabs, billets or the like.

The object of the invention is to provide tongs of this character which will operate automatically both for gripping or engaging the article and for releasing the same, these results being accomplished by raising and lowering the tongs, as by means of a crane.

One of the objects of my invention is to provide means which will hold the tongs in one or more predetermined open or closed positions so that the tongs may engage automatically to lift one piece or a plurality of pieces which are placed one above the other.

Another object of my invention relates to tongs which operate automatically for gripping the article on engagement therewith and for lifting the same and for automatically disengaging the tongs when the article is deposited in the desired location.

Another improvement in my invention relates to the locking latch and the shield lever which are operated automatically during the lifting and lowering operations of the tongs to alternately cover or uncover the entrance of the lower upwardly extending hook member.

With the foregoing and other objects in view the invention will be more fully described hereinafter, and will be more particularly pointed out in the appended claims.

Referring now to the accompanying three sheets of drawings which form a part of this specification and in which like characters of reference indicate like parts.

Figure l is a front elevation of the tongs showing it gripping a single bar or slab in the position it will assume at the beginning of the lifting operation.

Fig. 2 is a side elevation of the tongs shown in Fig. 1.

Fig. 3 is a detail of the handle for manually operating the adjustment lever.

Fig. 4 is a front elevation of the tongs in the position it will assume for lifting three bars or slabs just after the tongs have been lowered into engagement therewith and before the gripping jaws are closed thereon.

Fig. 5 is a front elevation of the lower upstanding hook detached.

Fig. 6 is a side elevation of the hook shown in Fig. 5.

Fig. 7 is a top plan view of the adjustment lever.

Fig. 8 is a front elevation of the shield lever detached.

Fig. 9 is a side elevation of the shield lever shown in Fig. 8.

Fig. 10 is a side elevation of the locking latch.

Fig. 11 is a detail view showing the pivoted hanging hook engaging the lower end of the locking latch which is in the raised position and the shield lever disengaged therefrom with the front plate of the upwardly extending hook removed to more clearly show the construction.

Fig. 12 is a similar view but showing the pivoted hanger hook disengaged and the locking latch in the lower position and the swinging end of the shield lever in its lower postion to close the entrance to the upstanding lower hook member. i

2,745,695 Patented May 15, 1956 Fig. 13 shows the pivoted hanger hook just after it has raised the shield lever and the locking latch lowered, and Fig. 14 shows the pivoted hanger hook lowered ready to be moved into the lifting position and the shield lever locked in position by the locking latch.

For illustration I have shown the tongs especially adapted for lifting and transporting articles such as rectangular shaped bars or slabs but it will be understood that the tongs may be used for other shapes equally as well.

Referring now to the various characters of reference on the drawings, the numerals 1 and 2 indicate the male and female members of the tongs which are pivoted together at an intermediate point by means of a pin 3, each tong member having a downwardly extending arm 4 provided with gripping jaw 5 secured thereto and an upwardly extending tong lever arm 6. Diagonally extending male and female links 7 and 8 are pivotally connected by means of pins 9 and 10 to the upper ends of the tong lever arms 6 respectively, and are connected together at the inner ends by a pin 11 which also secures a clevis 12 by means of which the tongs may be suspended from a suitable support such as an overhead crane or the like (not shown).

The male and female links 7 and 3 consist of steel plates cut to the desired contour and held in proper spaced relation by welded connecting plates 13 and 14.

The male tong member 1 is provided with an upwardly extending hook 15 which is welded thereto centrally above the pivot pin 3. This upwardly extending hook 15 is provided with side plates 16 and 17, the lower portions of which are connected together by means of a plate 18 welded thereto, and the top portions of plates 16 and 17 are held in spaced relation for receiving a shield lever 19 by means of plates 20 and 21. The upper portion of the hook 15 is also provided with a rectangular shaped recess 22 and a slideway 23 for receiving a locking latch 24 having side plates 25 connected at the top by a rod 26 square in cross section to engage the recess 22 and at the bottom ends by means of a rod 27 having a rounded upper surface adapted to be received in' the recess 28 of the hook 15.

The shield lever 19 has one end pivoted to the side plates 16 and 17 as at 29, and comprises a nose portion 30 adapted to normally close the entrance 31 to recess 28 of the lower hook 15 and is provided with a shoulder 32 adapted to be engaged by the upper swinging hook member 33 upon the operating of the tongs, to rotate the shield lever 19 to uncover the entrance 31 to the lower hook member 15. This shield lever 19 is also provided with a second shoulder 34 which is adapted to be engaged by the rod 26 of the locking latch 24 mounted in the slideway 23 in the lower hook member 15 to retain the shield lever in its last mentioned position so that the upper swinging hook 33 may engage the recess 28 in the lower hook member when the tongs are lifted to retain the tongs in their open position until they are again lowered.

' The upper end of the swinging member 33 has its upper end 35 pivoted on the pin 11 between the inner ends of the diagonally extending links 7 and 8 and is weighted or enlarged as at 36 to normally hold the swinging hook 33 in a vertical position and is also provided with a stop projection 37 for engaging a stop plate 38 which is welded to link 7 for limiting its forward swinging movement.

In order to automatically lift one or more slabs or the like in one operation an adjustment lever 39 of the toggle link type is used which is pivotally connected to the lower portions of the tong members 1 and 2. These links are each formed with side plates secured together in spaced relation and attached to the outer faces of the tong members. One of the toggle link members 40 is shorter than the other and has its outer end pivoted by means of a bolt 41 to the tong member 2, while the inner end is pivoted by means of a bolt 42 to the lower end of a somewhat longer link 43 which is mounted for adjustment on the tong member 1 by means of a pin 44, which extends through the tong member 1 with its ends projecting beyond the side faces to engage notches 45, 46 and 47 in the side flanges of the link 43.

The upper ends of side plate flanges of link 43 are connected together by means of a bolt 48-and also provided with pipe spacer 49 secured in place by means of a bolt 50.

In order to' assist in adjusting the toggle link a bracket 51 is Welded to the top end portion of the female tong member 2 in which is mounted a sheave 52 by means of a bolt 53 for receiving a wire rope 54, the lower end of which is secured to the bolt 42, while the upper end portion extends around the sheave 52 and the end secured to a handle 55 and is further provided with a counterweight 56 to assist in balancing the adjustment lever 39 if desired.

The tongs operate automatically in the following manner: Assuming that the books 15 and 33 are in engagement with each other and the parts are in the positions indicated in Figs. 4 and 11 a crane having a connection with the clevis member 12 can lift and transport the tongs to the desired location. The tongs are then lowered slowly until the central portion of the adjustment lever 39 engages the slabs 57 or the like as indicated in Fig. 4.

In this position the locking latch 24 will be raised above the shield lever 19. The upper swinging hook 33 will then be lowered slightly until it assumm the position shown in Fig. 12 with the locking latch 34 down and the nose portion 30 of the shield lever 19 closing the entrance 31 to the recess 28. The swinging hook 33 will then be raised thereby engaging the shoulder 32 of the shield lever 19 thereby rotating it into the position shown in Fig. 13, and during this operation the gripping jaws will be moved into gripping engagement with the slab as shown in Fig. 1. The crane can then lift and transport the slab to the desired location during which time the free end of the shield lever 19 will swing slightly downward until the shoulder 34 engages the rod portion 26 of the locking latch 24 thereby holding the shield lever 19 in the 4 position shown in Fig. 14.

After the slab or the like has been deposited wherev desired, the swinging hook 33 is again lowered to the position shown in Fig. 14 thereby opening the jaws.

The swinging hook 33 can then be raised into the position shown in Figs. 4 and 11 and the operations above described repeated.

In Fig. 1, I have shown the adjustment lever 39 in the position it will assumefor engaging and lifting one bar or slab, and for this purpose the ends of the pin 44 are inserted in the upper notches 47 of the side flanges of the link 43. If it is desired to lift two slabs at one time the ends of the pin 44 will be inserted in the notches 46 as indicated in dotted lines in Fig. 4. Hit is desired to lift three slabs the ends of pin 44 will be inserted in the lower notches 45. During the adjustment of the lever the upper end of the link 43 is swung inwardly manually so that the ends of the pin 44 will be disengaged from the notches 45, 46 or 47 and then reinserted in the desired notch. The handle and the wire rope connection 54 with the bolt 42 may be employed to assist in this operation.

Although I have shown and described my invention in considerable detail, I do not wish to be limited to the exact construction shown and described, but may use such substitutions, modifications or equivalents thereof, as are embraced within the scope of my invention, or as pointed out in the claims.

,1 claim:

e 1. In an article handling tong, comprising a pair of tong levers pivoted together at an intermediate point, each having a downwardly extending arm with gripping jaws mounted thereon and an upwardly extending lever arm, a link pivoted to the upper end of each lever arm, a pin for pivotally connecting the inner ends of the links having an upper hook mounted thereon for swinging movement, means connected to the pin for suspending and movably supporting the tong, a lower fixed hook positioned upright on one tong member, a shield pivotally mounted in the lower hook member having a movable swinging nose portion adapted to normally close the entrance to the recess of the lower fixed hook member and provided with a shoulder adapted to be engaged by the upper swinging hook member upon the operation of the tong to rotate the nose of the shield to uncover and open the entrance to the recess in the lower hook member, and a locking latch for holding the shield in the open position.

2. In an article handling tong, comprising a pair of tong levers pivoted together at an intermediate point, each having a downwardly extending arm with gripping jaws secured thereto and an upwardly extending lever arm, a lower fixed hook positioned upright on one of the tong levers, a link pivoted at its outer end to the upper end of each lever arm, a pin pivotally connecting the inner ends of the link having an upper hook mounted thereon for swinging movement, a stop for limiting the swinging movement of the hook, means connected to the pin for suspending and movably supporting the tong, means adapted to move the upper hook laterally out of engagement with the lower hook during the downward movement of the tong when engaging an article, a shield pivotally mounted in the lower hook member having a movable swinging nose portion adapted to normally close the entrance to the recess of the lower fixed hook member and adapted to retain the upper hook out of engagement with the lower hook during the upward movement of the tong in lifting an article.

3. In an article handling tongs comprising a pair of tong levers pivoted together at an intermediate point, each having a downwardly extending arm with a gripping jaw rigidly mounted thereon and an upwardly extending lever arm, a pair of links pivoted to the upper end of each lever arm, a pin pivotally connecting the inner ends of the pairs of links having an upper hook mounted thereon for swinging movement, a clevis mounted on the pin for suspending and movably supporting the tongs, a lower fixed hook positioned upright on onetong member, means on said lower fixed hook to swing the upper hook laterally into or out of engagement with the lower hook during the vertical movement of the tongs, and an adjustment lever of the toggle link type having its outer ends pivotally connected to the downwardly extending arms of the tong levers, the total length of said adjustment lever being greater than the combined distances from the pivot point of the tongs to the pivot points connecting the adjustment lever to said downwardly extending arms, said adjustment lever being adapted when the tongs are lowered for the central portion of the adjustment lever to contact with the article for holding the gripping jaws of said tongs in a plurality of open positions.

4. In an article handling tongs, comprising a pair of tong levers pivoted together at an intermediate point, each having a downwardly extending arm with a jaw rigidly mounted thereon and an upwardly extending lever arm, a pair of links having their outer ends pivoted to the upper end of each lever arm, a vpin pivotally connecting the inner ends of the pairs of links, an upper hook mounted thereon for swinging movement, a stop for limiting the swinging movement of the upper hook,

move the upper hook laterally out of engagement with the lower hook during the downward movement of the tongs when engaging an article, and a shield pivotally mounted in the lower fixed hook member having a movable swinging nose portion adapted to normally close the entrance to the recess of the lower fixed hook and adapted to retain the upper hook out of engagement with the lower hook during the upward movement of the tongs in lifting an article.

5. An article handling tongs, comprising a pair of tong levers pivoted together at an intermediate point, each having a downwardly extending arm with a gripping jaw secured thereto and an upwardly extending lever arm, a link having one end pivoted to the upper end of each lever arm, a pin pivotally connecting the inner ends of the links having an upper hook member mounted thereon for swinging movement, a clevis mounted on the pin for suspending and movably supporting the tongs, a lower fixed hook positioned upright on a tong member, a recess formed in the lower fixed hook, means on the lower fixed hook adapted to swing the lower end of the upper hook laterally to release it from the lower hook and actuated by the lowering of the tongs, a shield pivotally mounted in the lower hook member having a movable swinging nose portion adapted to normally close the entrance to the recess of the lower hook, said shield having a shoulder adapted to be engaged in raising the upper hook in lifting the article to rotate the shield to open the entrance to the recess in the lower hook member, and a locking latch for holding the nose of the shield in the raised open position.

6. In an article handling tongs, comprising a pair of tong levers pivoted together at an intermediate point, each having a downwardly extending arm with a gripping jaw rigidly mounted thereon and an upwardly extending lever arm, a pair of links having one end pivoted to the upper end of each lever arm, a pin pivotally connecting the inner ends of the links having an upper hook mounted thereon for swinging movement, a clevis mounted on the pin for suspending and movably supporting the tongs, a lower fixed hook positioned upright on a tong member, a recess formed in the lower fixed hook, means on the lower hook for swinging the lower end of the upper hook laterally out of engagement with the lower hook during the downward movement of the tongs when engaging the article, a shield pivotally mounted in the lower fixed hook having a movable swinging nose portion adapted to close the entrance to the recess in the lower hook member and to retain the upper hook member out of engagement with the lower hook member during the upward movement of the tongs in lifting the article, said shield having a shoulder adapted to be engaged by the upper hook member during its upward movement in lifting the article to rotate the shield to open the entrance to the recess of the lower fixed hook member.

7. In an article handling tongs, comprising a pair of tong levers pivoted together at an intermediate point, each having a downwardly extending arm with a gripping jaw secured thereto and an upwardly extending lever arm, a pair of links pivoted to the upper end of each lever arm, a pin pivotally connecting the inner ends of the pairs of links having an upper hook mounted thereon for swinging movement, a clevis connected to the pin for suspending and movably supporting the tongs, a lower relatively fixed hook positioned upright on one tong member, a recess and a slideway formed in the relatively fixed hook, a locking latch mounted in the slideway, a shield lever pivoted to the lower hook provided with a shoulder adapted to be engaged by the upper swinging hook member upon the operating of the tongs to rotate the shield lever to uncover the entrance to the recess in the lower relatively fixed hook member.

8. In an article handling tongs, comprising a pair of tong levers pivoted together at an intermediate point,

each having a downwardly extending arm with a gripping jaw secured thereto and an upwardly extending lever arm, a link pivoted to the upper end of each lever arm, a pin pivotally connecting the inner ends of the links having an upper hook mounted thereon for swinging movement, a clevis pivoted on the pin for suspending and movably supporting the tongs, a lower fixed hook positioned upright on one tong member, a recess formed in the lower fixed hook, means on said lower hook adapted to swing the lower end of the upper hook laterally out of engagement with the lower hook during the downward movement of the tongs into engagement with the article, a shield pivotally mounted in the lower hook member having a swinging nose portion adapted to normally close the entrance to the recess in the lower hook member to retain the lower end of the upper hook out of engagement with the lower hook during the upward movement or" the tongs when lifting the article, said shield having a shoulder adapted to be engaged by the upper hook during its upward movement to raise the nose portion of the shield to open the entrance to the recess to the lower hook, a locking latch for holding the nose portion of the shield in the raised position to permit the upper hook to engage the lower hook upon the downward movement of the tongs in releasing the tongs from the article and to lock the tong in the open position while is being lifted from the article.

9. in an article handling tongs, comprising a pair of tong levers pivoted together at an intermediate point, each having a downwardly extending arm with a gripping jaw secured thereto and an upwardly extending lever arm, a pair of links having their outer ends pivoted to the upwardly extending lever arms, a pin pivotally connecting the inner ends of the links, having an upper hook mounted thereon for swinging movement, a clevis mounted on the pin for suspending and movably supporting the tongs, a lower fixed hook positioned up right on a tong member having a recess formed therein, a shield pivotally mounted on the lower hook member having a forward swinging nose portion adapted to normally close the entrance to the lower hook member, a shoulder extending from the shield member adapted to be engaged by the upper hook member in its upward movement upon the opening of the tongs to rotate the shield to uncover the entrance to the lower hook memher, a vertically extending slideway formed in the lower hook member, a locking latch mounted for vertical movement in the slideway, a second shoulder extending from the shield adapted to be engaged by the locking latch mounted in the slideway of the lower hook member to retain the nose of the shield in the raised position to permit the upper hook member after being lowered to engage the lower hook when the tongs are again lifted to retain the gripping jaws of the tongs in their open position until the tongs are again lowered.

10. in an article handling tongs, comprising a pair of tong levers pivoted together at an intermediate point, each having a downwardly extending arm with a gripping jaw secured thereto and an upwardly extending lever arm, a pair of links having their outer ends pivoted to the upwardly extending lever arms, a pin connecting the inner ends of the links having an upper hook mounted thereon for swinging movement, a clevis mounted on the pin for suspending and movably supporting the tongs, a lower fixed hook positioned upright on a tong member below the upper swinging hook having a recess formed therein, means on said lower fixed hook adapted to swing the lower end of the upper hook member into or out of engagement with the recess in the lower hook member, a shield pivotally mounted on the lower hook member having a forward swinging nose portion adapted to normally close the entrance to the lower hook member, a shoulder extending from the shield member adapted to be engaged by the upper hook member in its upward movement upon the operation of the tongs to rotate the shield to uncover the entrance of the recess in the lower hook member, a vertically extending slideway formed in the lower hook member, a locking latch mounted locking latch mounted on the slideway of the lower hook member to retain the nose of the shield in the raised position, and means when the upper hook member is in operative relation with the lower hook member to elevate the locking latch above the second shoulder of the shield for the shield to return to its normal position to close the entrance to the recess to the lower hook member.

-11.'Article handling apparatus comprising a pair of tongs pivotally connected at a point intermediate their ends, each tong having a downwardly extending jaw member and an upwardly extending lever arm, and a pair of toggle links having their outer ends pivotally connected to said jaw members, the combined lengths of said toggle links being greater than the combined distances from the pivot point of the tongs to the pivot points connecting said links to said tongs.

'12. Article handling apparatus comprising a pair of tongs pivotally connected at a point intermediate their ends, each tong having a downwardly extending jaw member and an upwardly extending lever arm, latching means on said tongs adapted on successive cycles of raising and lowering the itongs to alternately hold the jaws open and closed, and a pair of depending toggle links having their outer ends pivotally connected to said jaw members, the combined lengths of said toggle links being greater than the combined distances from the pivot point of the tongs to the pivot points connecting said links to said tongs,

13. Article lifting apparatus comprising a pair of tongs pivotally connected at a point intermediate their ends, each tong having a downwardly extending jaw member and an upwardly extending lever arm, stop means secured to said tongs and projecting downward between said jaws and adapted to contact the article to be lifted,

and means for varying the amount of downward projection of said stop means.

References Cited in the file of this patent UNITED STATES PATENTS 715,746 Boax Dec. 16, 1902 1,966,240 Erdahl July 10, 1934 2,337,177 Breslav Dec. 21, 1945 2,384,396 Peyer Sept. 4, 1945 FOREIGN PATENTS 2,766 Great Britain 1911 622,179 Germany Nov. 22, 1935 Wim

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