Rown v. Brake Testing Equipment Corp.

38 F.2d 220, 1930 U.S. App. LEXIS 2293
CourtCourt of Appeals for the Ninth Circuit
DecidedFebruary 17, 1930
DocketNo. 5939
StatusPublished
Cited by14 cases

This text of 38 F.2d 220 (Rown v. Brake Testing Equipment Corp.) is published on Counsel Stack Legal Research, covering Court of Appeals for the Ninth Circuit primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Rown v. Brake Testing Equipment Corp., 38 F.2d 220, 1930 U.S. App. LEXIS 2293 (9th Cir. 1930).

Opinion

DIETRICH, Circuit Judge.

Below, the appellees and the appellant were, respectively, plaintiffs and defendant, and herein they will be so designated. One of the plaintiffs is the owner of Brennan patent, No. 1,264,770, and the other is a licensee thereunder. The defendant, who, in his automobile shop at San Francisco, uses a brake-testing device, known as the “Jumbo,” and manufactured by the Price-Hollister Company of Rockford, 111., is sued upon the ground that he thus infringes the patent. The only claim presently involved is No. 1, which the lower court held valid and infringed. It is as follows:

“A brake tester comprising means engaging a wheel element for rotating a wheel against the action of its brake and means associated therewith for indicating the resistance of the brake, together with means for temporarily supporting the wheel during the operation of said brake tester.”

The patent issued April 30,1918, upon an application filed April 24,1916. In his specifications the patentee declared that his “invention relates to a brake-testing device, particularly designed for testing the brakes of an automobile,” and that its object “is to provide a simple and inexpensive device for the purpose which may be readily applied either in a garage or elsewhere to determine whether or not the brakes are in proper working condition.” Pointing out the danger of operating ears with imperfect brakes, particularly in urban communities, he asserted that the only known means of discovery of defects was by observation in the actual operation of the ear upon the road. It was particularly desirable, he stated, “that a portable device be provided for instant test use, since a ear may behave quite differently when taken stagnant in a garage, from the manner in which it behaves after it has been driven for a while.”

In his drawings he exhibits the device in six different forms. In the first form it is a very simple one, consisting of a hand lever similar to a cant hook, with one end adapted to engage the wheel hub, and about a spoke’s length from this end provided with a swinging hook attached to "the lever by means of an intermediate spring fitted with a device for registering the degree of pressure applied. In operation, the wheel is driven upon a low platform where it rests upon cylindrical rollers, which revolve freely as the wheel is rotated. One end of the lever is placed upon the hub of the wheel, the hook is engaged with the outer end of a spoke, and to rotate the wheel the operator lifts upon the outer end of the lever. With the brake applied, its efficiency is measured and registered by the spring and attached gage. It will at once be seen that with the wheel thus relieved of ground friction an operator can approximate the same result by lifting directly upon a spoke and estimating the pressure applied. Functionally, the lever serves only to elongate the spoke and thus increase the operator’s power; and for his estimate of the force applied is substituted the more accurate mechanical gage.

In the second form the fulcrum end of the lever is made to rest upon an independent pedestal instead of upon the hub, and, in the third, the gage spring is differently located. In figure 4, instead of the spring gage, there is a pneumatic pressure chamber. Obviously these differences are not highly material. Figures 7 and 8, without modification of essential principles, show forms adapted for application to wheels with wire spokes and of the solid type. They exhibit no differentiating inventive novelty.

The form exhibited in figures 5 and 6,-the patentee states, is'particularly adapted for use upon heavy trucks, his description of it being substantially as follows: The wheel to- be tested is run up the end incline of a supporting block or platform and positioned upon a roller bearing plate carried by the block. The surface of the plate is preferably corrugated to avoid slipping of the wheel thereon. Pivoted in the body of [222]*222the block is the testing lever, fitted with a gage similar to that already described, the stem of which is secured to the outer end of a subsidiary lever, the opposite end of which is pivotally connected with the roller plate. As the testing lever is lifted or lowered, its tendency is to move the roller bearing plate backward or forward, thus rotating the wheel a short distance against the resistance of the applied brake; and such resistance is measured by the gage.

The problem of providing braking equipment for the modem automobile is not a simple one, for both efficiency and provision for safety are requisite. Brakes may be reasonably effective quickly to slow down or stop a rapidly moving car, but their application may impair steering control or be attended with other danger. Generally, ears are provided with four-wheel brakes, and obviously maladjustment as between the two front wheels will directly affect the steering; and to some extent the same consideration applies to the rear wheels. Opinions may differ upon the question whether as between the rear and the front wheels the brakes should be equally powerful or should apply simultaneously, but, as between the front wheels or the rear wheels, it is agreed that not only should the brakes be of the same capacity,' but that at any instant and under, any given degree of applied power they should be equally effective. And at any given time there should be a predetermined relation between the efficient power of the front and of the rear brakes. Moreover, for reasons well understood, a dependable test and accurate adjustment can be made only under conditions substantially the same as those which actually prevail upon the road with the wheels bearing the weight of the ear and making complete revolutions.

Thus to state the problem is at once to raise the question of how far Brennan contributed to its solution. Not only is the means suggested crude, but his conception was wholly inadequate. If patentable novelty be assumed, he provided only a small portable device, of some value, particularly in eases of emergency. Without it the operator could, upon raising the wheel from the ground by means of a common jack, and then lifting on the rim to turn the wheel against the applied brake, make a rough estimate of brake action. As already suggested, Brennan’s test lever increases the operator’s power by elongating the lever naturally afforded by the wheel itself, his meter is more accurate than the operator’s “feel,” and the roller block or platform may generally be preferable to a jack. But plainly he provided no means for, nor apparently did' he have any conception of, a test and adjustment under the conditions actually prevailing on the road, to meet which the brakes are necessarily employed. (When w!e remember that, owing to the overhanging fender, the possible stroke of his test lever is very short, it will be seen how inadequate must be the possible “slip” of the brake band upon the drum for a dependable test, especially for purposes of synchronization. And in attempting such a test there is scarcely room or time to apply the brake while the drum is in motion, so that with the brake first set the operator must overcome the factor differentiating friction at rest from friction in motion.

Furthermore, of two brakes which are equally effective when applied with full force, one may grab more quickly than the other, or, when partially applied, one may develop more frictional resistance than the other. It would hardly be contended that with the Brennan device there would be any certainty of detecting such disparities or making adjustments therefor.

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38 F.2d 220, 1930 U.S. App. LEXIS 2293, Counsel Stack Legal Research, https://law.counselstack.com/opinion/rown-v-brake-testing-equipment-corp-ca9-1930.