US1561081A

US1561081A - Piston

Info

Publication number: US1561081A
Application number: US553106A
Authority: US
Inventors: William E John
Original assignee: General Motors Research Corp
Current assignee: General Motors Research Corp
Priority date: 1922-04-15
Filing date: 1922-04-15
Publication date: 1925-11-10
Anticipated expiration: 1942-11-10

Description

Nov. 10, 1925 w. E. JOHN PISTON Filed April 15, 1922 Patented Nov. 10,1925.

A'l'ES WILLIAM'E. JOHN, OF DAYTON, OH IO, ASSIGNGB TO GENERAL MOTORS RESEARliH REOBATION, 0F DAYTON, QHIO, A CORPORATION OF DELAWARE.

PIS'EQN.

Application filed April 15, 192%. Serial No. 5,108.

To all whom it 71mg concern:

Be it known that l, WILLIAM E. JOHN, a citizen of the United States of America, residing at Dayton, county of Montgomery, and State oi @hio, have invented certain new and. useful Improvements in Pistons, of which'the following is a full, clear, and exact description.

This invention relates to pistons for internal combustion engines and has particular reference to. cooling means therefor. I

As is well known, a great problem in piston design is the provision of means to keep the piston cool enough to guarantee the proper operation thereof when the engine is working hard. Some of the diliiculties encountered are the excessive expansion' of the piston making it necessary to provide more clearance between the piston and cylinder walls; the excessive heating up of the central port of the top of the piston thereby reducing the compression which can be solely used without preiition end reducing the volumetric efliciency of the engine cylinder, and the dificulties of properly lubricating the piston. ..Also the high temperature of the central part or the top of the piston necessitates as? greater thic'zlr-v ness for strength considerations and therefore adds to the weight of the iston which for bolance considerations shou d be as light no possible.

Among the objects of the present invention is to enable it considerable decreese in weight oil cast iron pistons, at the some time providing for a heat conducting capacity equal to or greater than that oi thiclr sec tions commonly used.

in the drawing:

l is vertical section through the piston.

Fig. 2 is it view of the motel insert of high hoot conductivity which is cost in the piston, the left hell of the insert being shown in section.

Fig; 3 is or plan. view of the motel insert.

Sinnilnr reference charncters refer shin-- lnr ports thron #hout the several views.

Numeral id esignetes the metal insert, which is preierebly mode of sheet copper and of snhstentinll the same dimensions es the piston whici is-to be cost nronnd reasons. This insert 10 is set in the mold and the piston 15 cast about it in a manner which will he reedily understood by those skilled in the art. Preferably the insert 10 is provided with a plurality of small holes 11 having the metal turned in or out to form short flanges 12 around the holes. These flanges l2 aid in carrying theheat to the inner surface olthe piston where the heat is dissipated to the air and oil in the crank case of the engine. The top of the piston-may also have similar flanges 13 en tending upwardly, as shown, to aid in conducting the heat from-the upper surface of the piston down to the 00 per insert, The

flanges

12 and 13 prefers. ly extend to the surface of the cast metal, but if desired they may extend only to a point just below the surface of the cast metal.

The piston is preferably cast of cast iron.

on account of its coeflicient of expansion being the same as that of thee linder. wells, aring qual- 1ties,'but of. course the scope of the inven-' and because of its satisfactory tion includes the .use of other cast motels being used. The copper insert 10 greatly increases the heat conductivity over a sirni- 1 larpiston without the insert and hence the piston will run much cooler and all the attending advantages obtained. If desired,

the copper insertmay not extend the'lnlles the greetest u lid tendency to heat to the side walls of the piston. Gt course in any of the shove dcscribed modificotions any motel of gh heat conductivity mey he used for the inserts instead of copper.

While the form of mechanism herein shown and described constitutes e preferred form of embodiment of the present invention, it is to he understood that other forms might be adopted, ell coming within -the scope of the clnims which follow.

Whnt l eleim is es follows: l. A cast metal piston havi embedded within its heed a continuous insert of motel extending throughout seid heed end ot' illlil llll higher heat conductivity than said cast metal. v

2. A cast metal piston havin cast within its Walls an insert of metal 0 higher heat conductivity than said cast metal, said in sert having portions extending to the surface of the piston walls.

3. A cast metal piston having embedded within its head and skirt portions a continuous sheet metal insert of higher heat conductivity than said cast metal.

4. A cast metal piston having cast within its walls a sheet metal insert of higher heat conductivity than said cast metal, said insert having portions extending to the surface of said'cast metal.

5. A cast metal piston having cast within its walls a' continuous sheet metal on shaped insert of the general form of tile piston and having-higher heat conductivity than said cast metal.

In testimony whereof I hereto afiix my signature.

WILLIAM E. JOHN.