US475181A - Electrical m etal-h eater - Google Patents

Description

(No Model.) 2 Sheets-Sheet 1.

G. D. BURTON. ELECTRICAL METAL HEATER.

No. 475,181. Patented May 17,1892.

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(No Model.) 2 Sheets-Sheet 2.

G. D. BURTON.

. ELECTRICAL METAL HEATER. No. 475,181. Patented May 17,1892.

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R d m I ll g'lH I r 1 H i 2 D11 1 b E Ts WITNESSES l \l e Z a 1% UNITED STATES PATENT OFFICE,

GEORGE D. BURTON, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO THE ELECTRICAL FORGING COMPANY, OF MAINE.

ELECTRICAL METAL-HEATER.

SPECIFICATION forming part of Letters Patent No. 475,181, dated May 17, 1892.

Application filed May 26, 1891. Serial No. 394,108. (No model.)

To all whom it may concern:

Be it known that I, GEORGE DEXTER BUR- TON, a citizen of the United States, residing at Boston, in the county of Suffolk, in the State of Massachusetts, have invented certain new and useful Improvements in Electric Apparatus for Making Metal Forgings, of which the following is a specification.

The object of this invention is to produce metal forgings of superior quality in an economical manner, and especially to prod ucc twisted metal bars by the aid of electricity for stair-rods, fence-pickets, and ornamental metal-work in general.

Figure 1 of the accompanying drawings represents a side elevation of this improved apparatus in connection with an electric converter. Fig. 2 representsa plan view thereof. Fig. 3 represents a face view of the oscillating clamp for holding one end of the bar to be twisted. Fig. 4 represents a portion of a twisted bar.

Similar numerals of reference indicate corresponding parts in the diiferent figures.

The rings 10 and l1,where0f segments only are representedin the drawings, constitute parts of an electric-current converter, which need not be fully illustrated in this case. The ring 10 is provided with a boss 12 and the ring 11 with a boss 13, which bosses constitute the terminals of the converter. Abracket 20, composed of copper or other suitable conductive material, is attached at one end to the boss of the ring 10, and depends therefrom when arranged as shown in the drawings. A similar bracket 30, also composed of copper or other suitable conductive material, is attached to the boss or terminal 13 of the converter-ring 11 and depends therefrom. The outer ends of these brackets are provided with arms 21 and 31, respectively, which are preferably slotted longitudinallyand adjusted in line with each other in the same horizontal plane. The brackets and arms may be composed wholly or in part of iron or other material or composition of lower conductivity than copper, provided they be sufficiently large in proportion to the bars to be operated upon to carry a current adapted to heat such bars to a forging temperature without becoming overheated themselves.

Two clamps 40 and 50, composed of copper, iron, or other suitable conductive material, are adjustable, respectively, on the arms 21 and 31. These clamps or holders may be of any suitable construction for clamping the ends of the bar to be heated and twisted.

A bar-twisting apparatus is disposed on the arm 31. This bar-twister comprises two similar adjustable standards and 61, a shaft 70, journaled in said standards, and a clamp 71 at one end of said shaft for grasping one end of the bar to be twisted. A third standard 62, somewhat taller than the shaft-supporting standards, is disposed at the outer end of said arm 31. A stub-shaft 80 is journaled in said standard 62, and provided at one end with a beveled pinion 81 and at the other end with an actuating-crank S2. The outer end of the shank is provided with a beveled gear '72, which meshes with the pinion 81 on the stub-shaft 80. The clamp 71 comprises a rectangular frame 73, two sliding jaws 74 and 75, and set-screws 76 and 77, passing through the ends of said frame and engaging said jaws for adjusting them upon the end of the bar.

The standards 60, 61, and 62 are severally provided with lugs 63,which project downward through the slot in the arm 31, and said arm is provided at its outer end with a fixed dependent lug (it, having an insulating-bushing 65. A screw-rod 66 passes through the bushing 05 and through the lugs 63, and is provided with a hand-wheel 67 at its outer end. This screw-rod serves to adjust the twister on the arm 31.

In the use of this apparatus one end of a metal bar 100 to be twisted is placed in the clamp 40 and the other end in the clamp 50, said bar extending through the clamp 50 and the extended end thereof being engaged by the jaws of the clamp '71. Both the clamps 40 and 50 are closed tightly upon the bar and the electric current switched on. The current passes from the positive ring 10 of the converter through the bracket 20 or other conductor leading from said ring, thence through the arm 21, thence through the clamp 40, thence through the bar 100 to be heated to the clamp 50, thence through the arm 31 to the bracket 30, and through said bracket or its equivalent to the negative ring 11 of the converter. The rod 100, under the action of the heating-current, will be heated in a few seconds to a forging temperature throughout that portion of its length which spans the space between the clamps and 50, while the ends which are directly in contact with the clamps will remain cool in the metallurgical sense of t he term. The currentisthen switched off and the clamp released from the bar. The crank 82 is then turned, whereby the shaft and its clamp 71 are rotated, one end of the bar being still held in the clamp 40 and the other end in the clamp 71. The rotation of the shaft 70 causes a twisting of the bar, as represented in Figs. 1, 2, and 4. The bar may be twisted more or less, as desired, and is then released from the clamps and removed from the apparatus.

In the use of the electric currentfor heating bars or blanks, I have found that the bar or blank is heated from the interior instead of the exterior, as in the ordinary furnace-forge, and that there are no gases introduced into the metal when heated by electricity, and consequently when twisted no scale is formed and the metal is left clean and free from blem ishes. Moreover the bar retains the heat de- \V hen heated from the exterior,

the outer surface of the metal is broken, which causes the scale, owing to the fact that the exterior is overheated before the interior is heated to the required working temperature.

I claim as my invention-- 1. In an electric metal-working apparatus, the combination of two converter-rings constituting the positive and negative poles, two conductive brackets connected, respectively, to said rings and provided with horizontal arms, two clamps adjustable toward and fro m each other on said arms, two standards on one of said arms, a shaft journaled in said standards and provided with a clamp at one end, and means for rotating said shaft.

2. In an electric metal-working apparatus, the combination of two converter-rings eonstituting the positive and negative poles, two conductive brackets connected, respectively, to said rings and provided with horizontal arms, two clamps adjustable toward and from each other on said arms, two standardson one of said arms, a shaft journaled in said standards and provided with a clamp at one-end, means for rotating said shaft, and means for adjusting said standards on said arm.

GEO. D. BURTON.

Witnesses:

CHAS. F. ADAMS, F. C. SOMES.

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