US1957719A - Lifting device - Google Patents

Description

-Y H. M, NAUGLE ET AL. 1,957,719

LIFTING DEVICE Filed April 6, 1933 2 Sheets-Sheet 2 l5 INVENTORS EMA/a1; [a 23 A.J,7 0 w/25 Patented May 8, 193 4 UNITED STATES LIFTING DEVICE Application April 6, 1933, Serial No. 664,728

5 Claims.

The invention relates to grabs or lifting devices, and more particularly to lifting devices which may be used for grabbing, hoisting and conveying centrifugally cast massive ring blooms, and the like, which may weigh approximately one ton and upwards.

The manufacture of finished and semi-finished rolled steel products from massive ring blooms, slabs, billets and the like, preferably having cross sectional areas of sixteen square inches and upwards with minimum dimensions of three inches and circumferential lengths of twenty-five feet and upwards, directly from molten metal, and of the products set forth in our copending product application filed May 6, 1933, Serial No. 669,711, preferably in accordance with some or all of the methods set forth in our Patents No. 1,882,516, dated October 11, 1932, No. 1,908,168, dated May 9, 1933, No. 1,908,169, dated May 9, 1933, and No. 1,908,171, dated May 9, 1933, involves the use of centrifugal molding apparatus, preferably such as set forth in our application, entitled Centrifugal molding apparatus, filed April 6, 1933, Serial No. 664,727, in which an annular mold is utilized preferably comprising separable sections forming an annular inwardly opening mold cavity, removably mounted on a rotor.

In the manufacture of such massive rings, it is desirable, if not necessary, from many standpoints, to promptly remove the mold from the rotor after the molten metal has solidified to form a ring within the mold cavity, and to promptly strip the massive cast ring from the mold so that it may be promptly cut or severed to avoid cooling strains, and so that in certain cases severed arcuate sections thereof may be promptly placed preferably in a holding furnace, from which the same may be withdrawn for rolling, in order that as much of the original casting heat as possible may be retained by the ring, to reduce the heating charges for rolling.

The mold in which a massive ring is preferably cast comprises substantially similar upper and lower sections separable substantially in a median plane perpendicular to the axis of the ring. After such a mold has been removed by suitable crane tackle from the centrifugal casting apparatus rotor, the upper section of the mold is removed, leaving the cast ring lying fiat on the lower half of the mold. At this time, there is available only substantially the upper half of the outer annular surface of the ring and the inner annular surface of the ring, for engagement by gripping means for stripping the ring from the lower half of the mold.

t is desirable to utilize a lifting, hoisting and conveying device for picking up the ring to strip it from the lower half of the mold which engages the outer annular surface of the ring in a contracting, grab or claw-like manner, so that the weight of the ring tends to increase the hold of the gripping means thereof upon the ring during lifting, hoisting and conveying; rather than to utilize a lifting device which includes spreader means which expands to engage the inner annular surface of the ring, wherein the weight of the ring tends to reduce the hold of the spreader means.

It is therefore an object of the present invention to provide a device for grabbing, lifting, handling, hoisting, conveying and stripping a massive ring bloom from the mold of centrifugal casting apparatus, which includes tong-like, grabdike, or claw-like gripping means for grabbing or engaging by contraction, the available outer annular surface of a ring, as the ring rests upon the lower half of the mold.

It is a further object of the present invention to provide a massive ring bloom lifting device with locater means, which engage a portion of the massive ring for preventing the gripping means of the lifting device from engaging a portion of the mold, which would prevent the gripping means from engaging the outer annular surface of the ring.

It is a further object of the present invention to provide a lifting device for massive rings wherein a usual overhead travelling crane lifting magnet is utilized as a part of the lifting device, preferably for spreading the gripping means to open position when the lifting device is operated to grab or engage a massive ring; and wherein the weight of the said magnet, together with its magnetic attraction, is utilized for spreading the gripping means to load releasing position when the device is operated to release the hold of the gripping means upon a massive ring, after the ring has been conveyed to and deposited at the desired place.

It is a further object of the present invention to provide a lifting device for massive rings, which includes a usual overhead travelling crane lifting magnet removably incorporated in the lifting device, the said magnet when energized exerting magnetic attraction directly upon the frame of the lifting device for spreading the gripping means mounted on the frame to move the same to open or load-releasing position.

And finally, it is an object of the present invention to provide a lifting device in which the above desiderata are incorporated, not only for lifting massive ring blooms, but for grabbing, lifting, handling, hoisting, conveying and transporting any other desired objects, which lifting device has a simplified design, construction and operation, and which incorporates a removably mounted overhead travelling crane lifting magnet that may be removed and utilized for usual lifting purposes, when the improved lifting device is not in use.

The above and other objects may be obtained by the constructions, devices, parts, elements and combinations, 2. preferred embodiment of which is shown in the drawings, and is hereinafter described in detail and claimed, which may be stated in general terms as including in a lifting device, a head block, a lifting magnet removably suspended from the head block, a frame located below the lifting magnet provided with a plate for being attracted to the magnet, preferably bell crank gripping means pivotally mounted on the frame, and links pivotally connected to the bell crank gripping means and to the head block, whereby energization of the magnet draws the said attraction plate to the magnet to decrease the distance between the frame and head block and cause the said links to move the bell crank gripping means to open or load-releasing position.

While various modications and variations in the construction of the parts which comprise the improved lifting device will be apparent to those skilled in the art to which the invention appertains, a preferred embodiment of the present invention is shown in the drawings, in which:

Figure l is an elevation section of the improved lifting device with its gripping means in open position immediately after the device has been lowered upon a massive ring bloom lying substantially flat upon the lower half of a mold in which the ring bloom was centrifugally cast, taken as on the line 1-1, Fig. 3;

Fig. 2 is a view similar to Fig. 1, showing the improved lifting device immediately after the gripping means thereof have engaged a ring bloom and stripped it from its mold;

Fig. 3 is a plan sectional view of the parts shown in Fig. 1, taken on the line 33, Fig. 1;

Fig. 4 is a bottom plan view of the improved lifting device; and

Fig. 5 is a fragmentary elevation of the lifting magnet and lifting frame attraction plate in the position shown in Fig. 1, taken on the line 5-5, Fi 3.

Similar numerals refer throughout the drawings.

The improved lifting device includes a head block generally indicated at 6, which may preferably comprise a triangular plate member 7, provided with ears 8, to which chains 9 are attached at 10, the upper ends of the chains 9 being connected to the link 11, which may be engaged by the usual hook 12 of an overhead travelling crane.

The plate member 7 is preferably provided with a depending hook 13, upon which is removably suspended by chains 14 a usual type of lifting magnet 15. The lifting magnet 15 may be energized through wires 16 connected to the usual source of power and control means, not shown.

The lifting device also preferably includes a triangular frame generally indicated at 17, comprising preferably channel members 18 having angle members 19 secured to the ends thereof, there being spacers 20 connecting adjacent angle members 19 and spacers 21 connecting adjacent ends of the channel members 18.

to similar parts A plate 22 is preferably mounted on the frame 1'7 for being attracted to the lifting magnet 15, and the plate 22 is preferably normally spaced from the lifting magnet when the lifting magnet is deenergized as shown in Fig. 2. Angle brackets 23 are preferably mounted on the upper side of the plate for guiding the lifting magnet during relative movement between the same and the frame 17.

A bell crank 24 is pivotally mounted at 25 between a set of angle members 19; and one arm of each bell crank is preferably provided with a load engaging point 26, while the other arm of each bell crank is pivotally connected at 27 to a link 28, which is pivotally connected at 29 to an ear 8 of the head block plate member '7.

Energization of the magnet 15 causes the same to attract the plate 22 and draw the frame 17 toward the head block 6, whereupon the links 28, which support the frame actuate the bell cranks to a load releasing position, as shown in Fig. 1.

Upon deenergization of the magnet 15, the weight of the frame 1'7 operating by gravity pulls downward so that the links 28 actuate the bell cranks 24 toward a load engaging position, and when a load is engaged by the points 26, the weight of the load increases the pull of the frame 17 to tend to increase the grip of the load engaging means upon the work, as shown in Fig. 2.

ihe use of the improved lifting device for handling massive ring blooms is shown particularly in Figs. 1, 2 and 3 wherein a centrifugally cast massive ring bloom is generally indicated at 30 and the lower half of the mold in which the ring bloom was centrifugally cast is generally indicated at 31.

After the ring 30 has been cast in a mold on a rotor of suitable centrifugal casting apparatus, the mold with the cast ring therein is removed from the rotor to a suitable stripping station. At this time, the upper half of the mold is removed in any suitable manner, leaving the centrifugally cast ring bloom 30 lying substantially fiat upon the lower half of the mold 31, as shown in Fig. 1.

It is desirable, if not necessary, to promptly remove the massive ring bloom 30, which may have a cross sectional area of sixteen square inches and upwards with a minimum dimension of three inches and a circumferential length of twenty-five feet and upwards, from the lower half of the mold 31 so that it may be promptly cut or severed to avoid cooling strains, and so that in certain cases severed arcuate sections thereof may be promptly placed preferably in a holding furnace.

For this purpose, the improved lifting device carried preferably by an overhead travelling crane, is brought up to and located above the ring bloom 30 and the lower mold half 31. The improved lifting device is lowered to the position shown in Fig. l of the drawings wherein the ends of the channel members 18 engage and rest upon the upper surface of the ring bloom 30 to limit further downward movement of the lifting device for preventing the load engaging points 26 of the bell crank arms carrying the same from engaging the mold 21.

Meanwhile, the magnet 15 is energized to attract the plate 22 and the frame 1'7 carrying the same, to the magnet, which decreases the distance between the frame 17 and head block plate 7 so as to cause the links 28 to operate the bell cranks 24 to spread the load engaging points 26 to the open position shown in Fig. l.

Thereupon, the magnet 15 is deenergized and the crane hook 12 is raised to raise the lifting device, when the links 28 upon being pulled upward by the head block plate 7 operate the bell cranks 24 to a load engaging position so that the load engaging points 26 contract and engage the outer annular surface of the ring bloom 30, as shown in Fig. 2.

A continued raising of the crane hook 12 by the crane causes the ring bloom 30 to be stripped from the lower half of the mold 31, and the weight of the ring bloom 30 creates a further pull on the lifting device frame 17 to tend to increase the grip of the load engaging points 26 upon the ring bloom 30. In this manner, the ring 30 may be handled and transported to a cutting table where the lifting device is lowered to deposit the ring bloom on the cutting table.

Upon being lowered, the ring bloom 30 will first come to rest upon the cutting table, whereupon the weight of the magnet 15 continues to pull the head block downward until the magnet rests upon the plate 22 causing the links 28 to operate the bell cranks 24 to spread the load engaging points 26 thereof and to disengage them from the ring bloom 30. At this time, the magnet 15 may be energized to hold the load engaging points 26 in open or load releasing position, whereupon the lifting device may be raised and used for stripping another ring bloom from another mold.

If the points 26 should happen to stick while operating the lifting device to move the points to load releasing position, in such a manner as to hold the magnet 15 suspended, the magnet 15 may be energized to pull the same toward and in contact with the plate 22 to operate the bell cranks 24 to load releasing position.

Accordingly, an improved lifting device having a simplified design, construction and operation, incorporating a removably mounted overhead travelling crane lifting magnet, that may be removed and utilized for usual lifting purposes when the improved lifting device is not in use, is provided, for grabbing, hoisting, lifting, handling, conveying and transport ng centrifugally cast massive ring blooms.

While the improved lifting device has been described in connection with the handling of massive ring blooms, it will be apparent to those skilled in the art of lifting devices that various modifications and variations in the construction of the parts may be made for accomplishing the purposes of the present invention; and that the improved lifting device may be utilized for grabbing, lifting, handling, hoisting, conveying and transporting any desired objects or loads other than massive ring blooms.

We claim:

1. A lifting device including a head block, a lifting magnet, means suspending the lifting magnet from the head block, a frame located below and spaced from the lifting magnet, bell cranks pivoted to said frame, there being load engaging means provided on one of the arms of each bell crank, and a link for each bell crank pivotally connected to the other arm of each bell crank and to thehead block.

2. A lifting device including a head block, a lifting magnet, means suspending the lifting magnet from the head block, a frame located below the lifting magnet, a plate for being attracted to the magnet carried by the frame and spaced from the magnet, bell cranks pivoted to said frame, there being load engaging means provided on one of the arms of each bell crank, and a link for each beil crank pivotally connected to the other arm of each bell crank and to the head block.

3. A lifting device including a head block, a lifting magnet, means removably suspending the lifting magnet from the head block, a frame located below the lifting magnet provided with a plate spaced from the magnet for being attracted to the magnet, bell crank gripping means pivotally mounted on the frame, and links pivotally connected to the bell crank gripping means and to the head block.

4. A lifting device including a head block, a lifting magnet, means suspending the lifting magnet from the head block, a frame, load engaging means carried by the frame, and actuating means connecting between the head block and load engaging means to actuate the load engaging means when the frame is attracted to the magnet.

5. A lifting device including a head block, a lifting magnet, a hook carried by the head block, means suspending the lifting magnet from said hock, a frame located below said head block and magnet and spaced from the magnet, load engaging means carried by the frame, and actuating means connecting between the head block and load engaging means to actuate the load engaging means when the frame is attracted to the magnet.

HARRY M. NAUGLE. ARTHUR J. TOWNSEND.

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