US2231819A

US2231819A - Bit for lifting tongs

Info

Publication number: US2231819A
Application number: US290918A
Authority: US
Inventors: Rowe Andrew Reed
Original assignee: National Tube Co
Current assignee: National Tube Co
Priority date: 1939-08-18
Filing date: 1939-08-18
Publication date: 1941-02-11
Anticipated expiration: 1958-02-11

Description

Feb. 11, 1941. A, R ROWE 2,231,819

BIT FOR LIFTING TONGS Filed Aug. 18, 1959 4m 4 EEVi fE 0 Eon E, I

Patented Feb. 11, 1941 UNITED STATES PATENT OFFICE National Tube Company,

Jersey a corporation of New Application August 18, 1939, Serial No. 290,918

2 Claims.

This invention relates to bits for lifting tongs such as are employed for handling metallic ingots, blooms, billets or slabs.

In the lifting of heavy objects, such as those referred to hereinabove, the lifting tongs are usually provided with bits having working ends of pointed or convex shape. When a pointed or convex working end is employed the article being lifted (for example, a highly heated ingot) may be scarred to a depth of /2 to A of an inch, and this scar appears as a defect in the semi-finished product. In order to remove this defect, the object is conditioned by chipping or scarfing either manually or by a suitable machine. Any method by which the article is conditioned entails considerable expense.

In the case of a bit having a convex working point, the life of service is extremely short, as it must be redressed after several hours use. Such redressing is undesirable for the reason that the lifting tongs are out of service during the removal of the worn bits and the substitution therefor of suitably dressed bits.

In addition to the foregoing difiiculties bits having working ends of pointed or convex shape due to their penetration into a highly heated article (such as an ingot) pick up considerable heat and frequently must be cooled by dipping in water. This cooling is also objectionable, as in the case of replacement, as it curtails the productive work of the crane, charging machine, drawing machine or other apparatus employing the bit.

It is among the objects of the present invention to provide bits for lifting tongs which not only eliminate scarring of the object being lifted, but

which also have an enhanced life of service, thereby increasing the productive work of the apparatus employing the same.

The invention, then, comprises the features hereinafter fully described and as particularly pointed out in the claims, the following description and the annexed drawing setting forth in detail the certain illustrative embodiment of the invention, this being indicative of but one of the number of ways in which the principles of the invention may be employed.

In said annexed drawing:

Figure 1 is a perspective view of a conventional pair of tongs employing the bit of the present invention;

Figure 2 is an end view of the working end of the bit; and

Figure 3 is a side elevation, partly in section, of the bit of Figure 2.

Referring more particularly to the drawing, the numeral 2 designates a conventional pair of lifting tongs which may be of any suitable construction and provided with the usual arms 3 having recesses or apertures 4 for the reception of the lifting bits.

Referring more particularly to Figure 3, the numeral 6 shows the bit of the present invention which comprises a metallic frusto-conical body having one of its ends 1 of reduced diameter and constructed to occupy the recesses or apertures 4 in the arms of the lifting tongs 2. The frustoconical body 6 is provided with a cylindrical bore 8 and carries on its larger end an annular and continuous outwardly extending arcuate lip portion 9 formed on a single radius. This outwardly extending arcuate lip portion 9 comprises the working end of the bit of the invention, and due to its continuous arc, provides for reduced working contact with the article to be lifted. According to the prior art, the working ends of bits of the class described are of pointed or convex shape, as mentioned hereinbefore. The device of the invention embodying as it does the annular and continuous outwardly extending arcuate lip portion, provides a contact area of reduced width. Intermediate the bore 8 and arcuate terminal portion 9 the frusto-conical body 6 is provided with two angularly flared portions and H, the latter of which is narrower and of lesser angularity.

Due to the fact that the hollow or recessed working end of the bit of the invention does not penetrate as far below the surface of the object being lifted (such as a hot ingot), the bit picks up less heat and, consequently, does not have to be cooled as often by dipping in water. This, as before stated, adds to the life of the bit and also enhances the productive work of the apparatus employing the same.

While I have shown and described one specific embodiment of the present invention, it will be seen that I do not wish to be limited exactly thereto, since various modifications may be made without departing from the scope of the invention, as defined by the following claims.

I claim:

1. A bit for lifting tongs comprising a metallic body portion having a flared recess in its working end, said flared recess being connected to the periphery of said bit by an annular and continuous outwardly extending arcuate lip portion.

2. A bit for lifting tongs comprising a metallic body portion having a flared recess in its working end, said flared recess being connected to the outer periphery of said bit by an annular and continuous outwardly extending arcuate lip portion, the arc of which is based on a single radius.

ANDREW REED ROWE.