US1344875A

US1344875A - Process of making pistons

Info

Publication number: US1344875A
Application number: US236190A
Authority: US
Inventors: Flammang John
Original assignee: OTTMAR G STARK
Current assignee: OTTMAR G STARK
Priority date: 1918-05-23
Filing date: 1918-05-23
Publication date: 1920-06-29
Anticipated expiration: 1937-06-29

Description

J. FLAMMANG.

PROCESS 0F MAKING PISTONS.

APPLICATION FILED M^Y23| I9I8. 1,344,875. Patented June 29, 1920.

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UNITED STATES JOHN FLAMMANG, F ST. LOUIS, MISSOURI, ASSIGNOR TVO OTTMAR G. STAItK, OF ST.

PATENT oFFlcE.

LOUIS, MISSOURI. l

PROCESS 0F MAKING PVISTONS.

Specification of Letters Patent. Patented J une 29, 1920.

Application led May 23, 1918. Serial Nc.y 236,190.

T0 all whom t may concern.'

Be it known that I, JOHN FLAMMANG, a

citizen of the United States, residing at the city of St. Louis and State of Missouri, have invented a new anduseful Process of Making Pistons, of which the following is a specification.

This invention lrelates to the art of manufacturing pistons.

An object of the invention is to improve the art of manufacturing pistons whereby pistons may be produced that will impart uniform pressure against the cylinder wall all -around by the resiliency of the metal of which the pistons are composed, thus dispensing with the necessity of using piston rings or packing in connection with the pistons.

Additional objects and various advantages will ,appear from the followingy description in which reference is made to the drawings illustrating a piston in several stages of its construction in accordance with the present invention, and in which- Figure 1 is a view partly in section, illustrating a form of casting from which the piston is made.

Figs. 2 and 3 are views illustrating the casting after the upper portion thereof has been divided into segmental sections and the holes for the wrist pin have been formed.

Fig. 4 is a view illustrating the casting after it has been treated to cause the rev siliency of the metalto close the openings formed by cutting the upper portion of the piston body into segmental sections.

Fig. 5 is an elevation of the piston body after it has been subjected to additional treatment.

Fig. 6 is' a view of the piston body having -thev wrist pin mounted therein,jwhereby the within a cylinder.

The piston body is made from a casting including a lower ring 1, an upper ring 2,

connections 3 integrally uniting the lower and upper rings, and bosses ty through which the holes for the wrist pin are formed.

By my present invention the upper ring 2 of the piston body is vdivided into segmental sections, one of which is integrally united with each of the connections 3. The connections 3 also constitute supports for the free ends of the `segmental sections so that both ends of each segmental section are firmly and rigidly supported. The segmental sections are formed by horizontal cuts 5 and inclined or oblique cuts 6 yextending frorn the ends of the cuts 5 to the upper edges of the` upper ring. This leaves `one end of each of the segmental sections integrally united with one of theconnections, and the opposite end of each segmental section overlying a part of an adjacent connection 3. As shown the cuts 6 are oblique or inclined relative tothe axis of the piston, so that the ends of the segmental sections are overlapping. The piston body is then subjected to treatment, preferably by heat, to change the molecular arrangement of the upper ring 2 so that the free ends of the segmental sections will press upon theadj acent portions yof the connections 3 and thus close the cuts 5, as shown in Fig. 4. This treatment. may be effected by mechanically ypressing the free ends of the segmental sections to the positions desired and, while the piston toa dull red heat to change the molecular arrangement and set the material in that shape. After that has been done the upper edge or endof the piston body is ground or finished to provide a properly smooth surface upon which the removable top or head plate of the piston may be mounted. y j

,'At a desired time relative to the above stages oftreatment, the holes-7 for the wrist pins are formed through the connections 3 and the bosses 4. As shown and as preferred, the holes 7 are inclined inwardly and downwardly so that when the rwrist pin 8 is appliedv therein the connections 3 will kbe sprung and the segmental sections of the upper ring spaced apart. c

Either before or after the wrist pin is placed in the casting theexterior surface of the piston body is finished to a sizein which the diameter of the lower ring 1 is slightly smaller than the diameterjof the GTi cylinder for which the piston is intended, and in which the radii of the arcs of the connections 3 are also shorter than the radii of the cylinder in which the piston is to be mounted. The upper ring comprising the segmental sections above described is compressed to the position which it will occupy when placed in the cylinder and; while under compression, is inished to the same diameter as the diameter ofthe cylinder in which the piston is to operate. After being iinished the head or top plate 9 is removably connected to the upper segmental sections ofthe piston. The connection may be effected in any desired manner as by forming an interlocking tongue and groove connection lO between the top plate and the upper portion of the piston, or by the employment of locking keys ll engaging in slots in the upper ring of the piston and in grooves in the top or head plate; or7 if preferred, both of these connections may be employed as illustrated in Fig. 9.

The mounting of the wrist pin 8 in the inclined holes 7 retains the connections 3 in their sprung shape permanently so that mechanical pressure is applied to the connections 3 causing the full force of the resiliency thereoic to be exerted upon the segmental sections ot1 the upper ring.

Since the segmental sections of the upper ring have their ends approximately in the same vertical plane with the lines of expanding force, that is in approximately the same vertical plane with 'the axis of the wrist pin, it is clear that uniform or approximately uniform pressure will be exerted against the cylinder wall all around when the piston is placed therein. As shown in Fig. 8 the diameter of the top or head plate is the same as that of the cylinder in which the piston is to be mounted, while the diameter of the upper portion of the piston body when free from compression is slightly in excess of that of the head plate and also in excess of the diameter of the cylinder; although when the piston is mounted in the cylinder the upper portion of the piston is compressed as shown in Fig. 9.

Preferably, the ends of the segmental sections of the upper portion of the piston interlock so that the free end of each section will be held in annular alinement with the end of the adjacent section'which is integral with the connection 3. 1

It is apparent that the order in which many of the various steps ofthe process are formed is immaterial and may be varied without in the least departing from the principle of the invention, as set forth in the appended claims.

What I desire to secure by Letters Patent, 1s:-

1. The process of making a ypiston which mental sections which overlap said connections; and treating the piston body to cause the segmental sections to contact with said connections to close the spaces formed by splitting the upper ring.

3. The process of making a pistonV which consists in forming a piston body of Va lowerring, an upper ring, and connections integrally uniting the upper and lower rings; splitting the upper ring intosegmental. sections which overlap said connections; treating the piston body to cause the segmental sections to contact with said connections to close the spaces formed by splitting the upper ring; drawing the segmental sections of the upper ring toward each other to place the material under tension; and finishing the piston body to a size in which 'the upper ring while compressed' under tension is of the same diameter as the diameter of the cylinder for which the piston is intended.

4. The process of making a piston which consists in forming a piston body of a lower ring, an upper ring, and connections integrally uniting the upper and lower rings; splitting the upper ring into segmental sections which overlap said connections; treating the piston body to cause the segmental sections to contact with said connections to close the spaces formed by splitting the upper ring; drawing the segmental sections of the upper ring toward each other to place the material under tension; and finishing the piston body to a size in which the upper ring while compressed under tension is of the same diameter as the diameter of the cylinder for which the piston is intended, and in which the diameter of the lower portion of the piston body is less than the diameter of the cylinder for which the piston is intended.

5. The process of making a piston which consists in forming a piston body of a lower ring, an upper ring, and connections integrally uniting the lower and upper rings; splitting the upper ring into segmental sections which overlap each other; treating the segmental y sections to close the Vspaces formed by splitting the upper ring; drawing the segmental sections of the upper ring toward each other to place the material under tension; finishing the piston to a size in which the upper ring while compressed under tension is of the same diameter as the diameter of the cylinder for which the piston is intended; and mechanically holding the upper portion of the piston body under tension.

6. The process of making a piston which consists in forming a piston body of a lower ring, an upper ring, and connections integrally uniting the upper and lower rings; splitting the upper ring into overlapping segmental sections which overlap the connections between the upper and lower rings; treating the upper portion of the piston to close the spaces between the segmental sections and the connections; drawing the segmental sections of the upper ring toward each other to place the material under tension; finishing the piston to a size in which the upper ring while under tension is of the same diameter as the diameter of the cylinder for which the piston is intended; and mechanically holding said connections permanently under tension.

7. The process of making a piston which consists in forming a piston body of a lower ring, an upper ring, and connections integrally uniting the upper and lower rings; splitting the upper ring into overlapping segmental sections which overlap the connections between the upper and lower rings; treating the upper portion of the piston to close the spaces between the segmental sections and the connections; drawing the segmental sections of the upper ring toward each other to place the material under tension; finishing the piston to a size in which the upper ring while under tension is of the same diameter as the diameter of the cylinder for which the piston is intended; and in which the diameter of the lower portion of the piston body is less than the diameter of the cylinder for which the piston is intended; and

mechanically holding said connections permanently under tension.

8. In the process of makin a piston, the steps of causing a portiono the piston to press against the wall of the cylinder by the resiliency of the material of the piston, which comprises splitting the upper portion of the piston to form overlapping segmental sections; compressing the overlapping segmental sections; and forming the overlapping sections with the same radius of curvature as the radius of curvature of the cylinder forV which the pistony is intended, while said sections are compressed.

9. In the process of making a piston; the steps of causing a portion of the piston to press against the wall of the cylinder by the resiliency of the material of the piston, which comprises splitting the upper portion of the piston to form overlapping segmental sections; compressing the overlapping segmental sections; forming the overlapping sections with the same` radius of curvature as the radius of curvature of the cylinder for which the piston is intended, while said sections are compressed; and providing a top plate in connection with said overlapping sections.

10. In the process of making a piston, the steps of causing a portion of the pistonto press against the wall of the cylinder by the resiliency of the material of the piston, which comprises splitting the upper portion of the piston to form overlapping segmental sections; compressing the overlapping segmental sections; forming the overlapping sections with the same radius of curvature as the radius of curvature of the cylinder for which the piston is intended, while said sections are compressed; and interlocking a top plate with said overlapping sections.

JOHN FLAMMANG.