US2038754A

US2038754A - Piston

Info

Publication number: US2038754A
Application number: US366237A
Authority: US
Inventors: Adolph L Nelson
Original assignee: Individual
Current assignee: Individual
Priority date: 1929-05-27
Filing date: 1929-05-27
Publication date: 1936-04-28
Anticipated expiration: 1953-04-28

Description

' April 28, 1936';

A. L. NELSON PISTON 3 Sheets-Sheet 1 Filed May 27, 1929 4 hventoz: Z

35 mime l;

April 28, 19 36. r x NELSON 2,038,754

PISTON Filed May 27; I923 s Sheets-Sheet 2 F a-Z;

April 28, 1936. v A. L. NELSON PISTON Filed May 27, 1929 a Sheets-Sheet s avwentoz Q 351;, 14 WW a Patented Apr. 28, 1936 UNITED STATES PATENT OFF-ICE PISTON Adolph L. Nelson, Detroit, Mich.

Application May 27, 1929, Serial No. 366,237

Claims.

This invention relates to pistons for internal combustion engines, and particularly to such pistons for use in motor vehicles.

A particular object of the invention is to provide 5 a piston that may be formed of a light-weight material, such as an alloy of aluminum, in which each bearing face is braced on each side by a lateral tie extending from the bearing face to a part of the piston pin boss. The part of each pin 0 boss to which all or some of the ties are attached may be separated either partially or entirely from the remainder of the pin boss.

The invention is carried out by properly placing a spacing disc on each of the core pins thatare inserted in the mold to form the openings through the piston pin bosses. The piston metal is then poured in the usual way, and in the resulting piston the discs divide the bosses. By varying the shape of the disc and the adjacent piston parts it is possible to have the pin bosses either completely or only partially separated by the discs.

While preferred forms of the invention have been disclosed for purposes of illustration, it should be understood that various changes may be made in the structure or arrangement of parts Without departing from the spirit and scope of the invention as hereinafter set forth and claimed.

In the drawings: Fig. 1 is a side elevation of a piston embodying the invention.

Fig. 2 is an elevation, partly in section, taken at right angles to Fig. 1. v

Fig. 3 is a bottom plan view of the piston. Fig. 4 is a section taken on line 4-4 of Fig. 2. Fig. 5 is a. vertical section showing a modified orm of the invention.

Fig. 6 is an elevation, partly in section, of a further modification.

Fig. 7 is a partial vertical section of a different arrangement of the parts.

Fig. 8 is a plan view of the Washer used in the piston of Fig. 7.

Fig. 9 is a view similar to Fig. 7 but showing a still different modification. Fig. 10 is a section on line |0I0 of Fig. 9. V

Fig. 11 is a vertical section of another species. Fig. 12 is a section on line l2l2 of Fig. 11. Fig. 13. is a plan view of a modified washer. Referring to Figs. 1 to 4 more particularly, the reference character It! indicates the head of. the piston, and character H is applied to the piers which depend from the head and carry the piston pin bosses I2. The piston skirt includes a lower circular part l3 and cylinder-bearing portions I4 and 15. A tie it extends downwardly from each portion 15. These parts are formed of a suitable metal, such as an alloy of aluminum. 5 Each piston pin boss is divided into two parts, an outer part I9 and an inner part 20, by discs 2|. These discs may be of any material suitable for the purpose, but the preferred material is copper.

These discs are properly positioned on the core 10 pins that form the holes through the piston pin bosses, before the pins are inserted in the mold. The piston metal is then poured into the mold and after cooling the rough casting is removed from the mold in the usual manner. 15

In the piston illustrated in Figs. 1 to 4 the discs 2| are of such a size and shape that they completely divide the main body of each pin boss into two separate parts I9 and 20. It will be observed however, that these parts l9 and 20 are connected 20 to each other through the material of the reinforcing rib 22 which is homogeneous with the pier I I.

In the modification illustrated in Fig. 6 the arrangement of parts is similar to that of the form of Fig. 2 except that the ribs 22 are not present, and therefore the discs 2| completely separate the parts l9 and 20 of the pin bosses.

The species .of Fig. 5 embodies discs that are 30 elongated at the top, and the ribs 22 are widened where they envelope the upper edges of the discs.

In this case the

parts

19 and 20 of the pin bosses are united above through the material of the rib 22, but the split between the parts [9 and 20 ex- 35 tends farther away from the axis of the pin boss. The height of the upward extension on the disc can be varied to give any desired degree of flexibility between the two par-ts of the pin boss.

In the modification of Figs. 7 and 8 the disc 40 24 is formed with a notch 25, which is positioned in the mold in such a way that the piston material forms a tie on the lower side of the piston pin boss connecting the parts [9 and 20.

Figs. 9 and 10 also'show the tie at the lower side of the pin boss, but here a completely round disc is used, and the tie 26 extends below the disc. No special care in positioning is required with this form. 50

In Figs 11 and 12 the ties 21 are formed at one of the lateral sides of each boss. The figures also show the disc formed with a circular corrugation 28, which serves keep the disc in true shape for ease in handli g, and also holds the 55 disc firmly in place after the piston metal has been cast around it.

The pressed corrugation may be given an irregular form, as shown as 29 in Fig. 13, to further prevent movement of the disc.

A slot may be formed in one of the thrus faces, as indicated at 30. The thrust faces may also be relieved at their lateral edges. The relieved area may increase toward the upper edges of the thrust faces, such a form of relief being shown at 3| in Figs. 1 to 4. No relief is required where the bosses are completely divided as in Fig. 6. g

The use of discs as disclosed herein serves the same purpose as slots similarly disposed in the bosses, but the present means and method presents a. more eflicient and practical way of dividing the bosses than either using thin cores to cast the piston with the slots, or machining the slots after the pistons are cast.

It should be noted that this invention relates particularly to the method of dividing the pin bosses, and obviously the piston skirt can be made of any suitable form, may be sloted wherever desired, and may be supported from the piston pin bosses in any preferred manner.

By thus dividing the boss there is permitted a certain amount of flexibility and yielding between the two parts of the boss, the amount and character of the flexibility depending on the location and extent of the slot formed by the disc.

The discs also act as heat insulation between the two parts of each boss. This is true even where the discs are of. copper, as the hot piston metal when cast around the discs causes oxidation of the surfaces of the copper discs, and the piston metal therefore cannot lie close enough to these surfaces to form a joint having good heat transferring properties. As an added precaution it is possible to give the discs a preliminary coating to further insure a heat-insulating joint between the piston metal and the discs. It is also contemplated that the discs may be formed of a heat-insulating material such as high nickel steel.

The use o1 thin copper discs is particularly advantageous, as any piston castings that are imperfect can be re-melted without removing the discs, the slight percentage of additional copper being unimportant.

The discs can be formed with irregularities thatwill help to anchor them in place, or the discs may be intended for removal after the casting is made and may be formed with ears to facilitate such removal.

I claim:

1. A piston including a head and piston pin bosses, a spacing disc located in each pin boss, the spacing disc separating the boss into inner and outer parts, and a homogeneous tie connecting the inner and outer parts of the boss, the homogeneous tie being located at a. lateral side of the pin boss.

2. A piston comprising ahead, piers depending from the head, piston pin bosses formed in the piers, cylinder-bearing portions located on opposite sides of the piston, the upper ends of the cylinder-bearing portions being separated from the head and from the piers, ties connecting the cylinder-bearing portions to the piers, the head, piers, ties and cylinder-bearing portions forming a homogeneous mass of light-weight material, a spacing disc'located in each pin boss and serving to separate the boss intoinner and outer parts, said inner and outer boss parts being completely separate from each other except for ties connecting them together at one side of the boss only.

3. A piston comprising a head, piers depending from the head, piston pin bosses formed in outer parts, said inner and outer boss parts being completely separate from each other except for ties connecting them together at a lateral side of the boss only.

4. A piston comprising a head, piers depending from the head, piston pin bosses formed in the piers, cylinder-bearing portions located on opposite sides of the piston, the upper ends of the cylinder-bearing portions being separated from the head and from the piers, ties connecting the cylinder-bearing portions to the piers, the head, piers, ties and cylinder-bearing portions forming a homogeneous mass of lightweight material, a spacing disc locatedin each pin boss and serving to separate the boss into inner and outer parts, said inner and outer boss parts being completely separate from each other except for ties connecting them together at the lower side of the boss only.

5. A piston comprising a head, piers depending from the head, piston pin bosses formed in the piers, cylinder-bearing portions located on opposite sides of the piston, the upper ends of the cylinder-bearing portions being separated from the head and from the piers, ties connecting the cylinder-bearing. portions to'the piers, the head, piers, ties and cylinder-bearing pertions forming a homogeneous mass of lightweight material, a spacing disc located in each pin boss and serving to separate the boss into inner and outer parts, said inner and outer boss parts being completely separate from each other except for ties connecting them together at a point above the axis of the boss only.

ADOLPH L. NELSON.