United Parts Manufacturing Company v. Lee Motor Products, Inc., and Joseph Kumin

266 F.2d 20, 121 U.S.P.Q. (BNA) 206, 1959 U.S. App. LEXIS 5496
CourtCourt of Appeals for the Sixth Circuit
DecidedApril 22, 1959
Docket13558
StatusPublished
Cited by14 cases

This text of 266 F.2d 20 (United Parts Manufacturing Company v. Lee Motor Products, Inc., and Joseph Kumin) is published on Counsel Stack Legal Research, covering Court of Appeals for the Sixth Circuit primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
United Parts Manufacturing Company v. Lee Motor Products, Inc., and Joseph Kumin, 266 F.2d 20, 121 U.S.P.Q. (BNA) 206, 1959 U.S. App. LEXIS 5496 (6th Cir. 1959).

Opinion

SHACKELFORD MILLER, Jr., Circuit Judge.

The appellant, United Parts Manufacturing Company, is engaged in the manufacture and sale of replacement parts for motor vehicles, including hydraulic brake cylinders used in the hydraulic brake systems. It is the owner, by assignment from the patentee, of two patents, namely, Larson No. 2,412,587, issued December 17, 1946, hereinafter referred to as Larson 587, and Larson No. 2,435,837, issued February 10,1948. These patents are concerned with a structure whereby leaky and defective hydraulic brake cylinders employed in the hydraulic brake systems of motor vehicles are restored to safe operating condition. Appellant brought this action against the appellees alleging infringement by them of these patents, seeking preliminary and perma *22 nent injunctions and damages. Appellees denied validity of the patents and infringement. The District Judge held that the claims of patent Larson 587 were invalid and not infringed by the appellees and dismissed the complaint. Larson No. 2,435,887 is an improvement over and a continuation in part of the earlier patent, and since its validity must stand or fall on the validity of the earlier parent patent, the case was tried and considered by the District Court, and will be considered on this review, on the merits of the parent patent, Larson 587.

The conventional master hydraulic brake cylinder consists of a gray-iron casting divided into two compartments; an upper compartment which is a brake fluid reservoir tank and a lower compartment which is bored in the form of a horizontal cylinder. The lower compartment contains the operating parts of the mechanism. These component working parts consist of a master cylinder piston actuated by a push rod which is connected by a link to the brake pedal; a resilient rubber cup positioned at the head of the piston, the flexible end of the cup being in wiping or sealing relationship with the walls of the cylinder; a valve seated at the far end of the cylinder; and a coiled compression spring positioned between the piston head with its rubber cup and the valve. When the driver depresses the brake pedal, the push rod, one end of which is seated in the master cylinder piston, pushes the piston and the resilient rubber cup at its head forward, the cup wipes along the bore of the cylinder compressing the fluid, and the pressure engendered thereby is transmitted through the valve into the brake line forcing the brake shoes to expand against the rotating brake drums. Friction brings the vehicle to a halt. -Upon release of the brake pedal the coiled spring returns the piston and cup to the original or normal position permitting the valve to leave its seat and the fluid flows back into the cylinder and the reservoir, thus releasing the pressure upon the brakes.

If the smooth continuity of the cylinder bore is for any reason impaired, contact between the bore and the rubber cup is broken, the fluid will leak or seep backward past the cup and the cylinder head, dissipating the pressure in the cylinder and rendering the brake ineffective. It is necessary if the brake is to operate effectively that the cylinder bore, remain smooth and unmarred. However, after use the cylinder bore becomes pitted and corroded due to condensation or other deleterious conditions. The pits and corrosions in the cylinder bore cause the cup to lose contact with the wall on the forward stroke of the piston with the consequent backward leakage of the fluid. The wiping action of the cup, because of such leakage, can no longer create the pressure in the cylinder necessary to force the fluid into the line and, consequently, there is brake failure.

Under such conditions, it had been the usual practice to discard the casting and replace it with a new one. In addition to being an expensive practice, World War II presented an additional complication. Gray-iron was one of the allocated materials and new castings became unavailable. Accordingly, the honing method was used throughout the industry to meet this problem. A mechanic was furnished with a honing tool and manually removed just enough of the metal in the cylinder bore to eradicate the pits and corrosion found therein. It was necessary to maintain a uniform bore diameter so that the piston could operate therein. It was necessary to keep that diameter within such limits as would permit the use of standard size pistons and other operating parts. It was necessary to do this work at a cost which would enable the restored cylinder to be sold at a profit. The honing method had a number of disadvantages. There was no way of ascertaining, before work was started, how deep the pits were in the bore or how great the corrosion. In some instances, so much metal had to be removed from the bore that the casting became too weak to be used. In other in *23 stances, it because necessary to remove so much of the metal that the diameter of the bore was enlarged and oversize pistons and cups were required.

Larson 587 met the problem by providing a lined hydraulic brake cylinder wherein a sleeve or liner was secured in the cylinder bore without the use of any third member and in a manner so that the liner, when it in turn became pitted or corroded, could easily be replaced with a new one. The lined cylinder was equivalent in all respects to the cylinder bore of a new casting and would take standard size operating parts such as pistons and cups. A general description of the patent is as follows. The lower cylindrical chamber is enlarged by boring throughout its length except for a portion approximately %" wide at the right or high-pressure end. The unbored portion forms a 14" shoulder at that point in the cylinder whose diameter is less than that of the main body and which provides a press-fit with the outside diameter of a sleeve inserted therein. A tubular steel sleeve having an inside diameter identical to the diameter of the cylinder of the original casting and with its left end flared outwardly to form a truncated conical portion of greater diameter than the new bore is loosely inserted into the enlarged cylinder until it reaches the restrictive shoulder. The sleeve is then pressed home until it is completely enclosed in the cylinder. The shoulder forms a press-fit with the right end of the sleeve and the left or flared end of the sleeve, being under compression due to the resiliency of the steel, forms a gravity type seal with the cylinder wall at the low-pressure end. The inside diameter of the sleeve being the same as the diameter of the original casting, the piston and the cup are of standard size. The sleeve itself, although self-supported in the cylinder without the use of any third element, is actually spaced from the cylinder wall except at its two ends and may, therefore, be quickly and easily replaced.

The patent has four claims. Claim No. 1, which is typical, reads as follows:

“A cylinder lining comprising the combination thereof with a cylinder having a longitudinal inner bore of larger diameter than said liner, a shoulder on the said inner bore adjacent one end of said cylinder which press fits said liner, one end of said liner tapering outwardly, whereby when pressed into position the tapered portion will be compressed forming a tight union with the cylinder wall.”

Appellees contend that Larson 587 is invalid by reason of anticipation by the prior art and by prior use and because it lacks invention. The District Judge found for the appellees on each of these contentions.

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266 F.2d 20, 121 U.S.P.Q. (BNA) 206, 1959 U.S. App. LEXIS 5496, Counsel Stack Legal Research, https://law.counselstack.com/opinion/united-parts-manufacturing-company-v-lee-motor-products-inc-and-joseph-ca6-1959.