The opinion of the court was delivered by: KNIGHT
A rehearing was granted herein for the reconsideration of the patent to Taylor No. 1,438,507, and the consideration of the patent to Sutton No. 1,341,395, granted May 25, 1920. This was limited to the questions of anticipation and validity.
The plaintiff bases its suit for infringement on these features of its automobile shock absorber: (1) a three-part working casing with abutments integral with the intermediate member; (2) means for holding the three parts together in fixed relation; (3) and an automatic replenishment reservoir. It asserts that the problem in the shock absorber art had been (1) to secure a permanently rigid and accurate recovery chamber, (2) automatic replenishment of the working liquid, (3) freedom from leakage and service attention, and (4) adaption to low production; and that the aforesaid features of its device in the combination with the other parts shown solved these problems.
Taylor, like Pennington, is of the single vane or eccentric type and discloses an hydraulic shock absorber with a three-part working chamber casing held together by studs and bolts, rather than by cap screws and dowel pins or dowel bolts, as in Pennington, and abutments integral with the intermediate member. In Taylor the casing receptacle is movable and the vane (partition) immovable, and in Pennington the reverse is the operation, but the relative movements between the casings and vanes, effecting the pressure of the fluid within the chambers, are the same. Taylor does not show any reservoir for the recovery of leakage. Both show equal facilities for broaching the interior of the chambers and machining the re-entrance corners therein, and the interior contours of the working chambers are comparably alike. Concededly the Taylor device is inoperative as an effective shock absorber due to the fact that the link connecting the absorber and frame of the vehicle is pivoted on the absorber. There are other defects.
The Sutton patent discloses an hydraulic shock absorber with three-part working chamber casing in which the intermediate casing is provided with inwardly projecting abutment members integral therewith. It discloses a double action shock absorber of the balanced or concentric type. The abutments divide the two chambers in two parts, and vane and chamber casing function in the manner long known in the art. In Sutton the three parts are neither held together by bolts and screws nor dowel pins or dowel bolts. To secure them the front member may be either screwed in the open end of the cup-shaped member by threads on the inside of the cup, and this method is comparable with the accused structure, stipulated Exhibit C, and is the equivalent of the Houde 1922 structure in that respect, or it may be in the form of a cap provided with an "angular flange" which screws over the end portion of the intermediate member, as shown in the physical exhibit of the Sutton structure in evidence. Sutton does not disclose any method for automatic recovery of the leakage. It shows facilities for broaching or machining equal to those of Pennington. In this structure the casing is stationary and the vane movable.
The drawing below show the casings and vanes of the devices of Pennington, Taylor, Sutton and an accused structure:
[See Illustration in Original]
The drawings below show the three casing parts and hub and vane of Pennington and Taylor:
[See Illustration in Original]
Neither Taylor nor Sutton anticipates Pennington, since all the elements of Pennington are not found in either "performing substantially the same work in substantially the same way." Walker on Patents, Deller Ed., p. 255.
Johnson Patent No. 1,578,319, a prior art reference on the original trial, discloses a three-part concentrically arranged single vane type of shock absorber. There is no flat lateral surface engagement between the intermediate part and the other two parts, but grooves are provided in the outside parts to receive the end of the intermediate casing part. The parts are held together by cap screws, and lateral shifting is further prevented by the prooves in the flat surface which receive the ends of the intermediate part. It shows no dowel pins. It discloses no abutment or abutments integral with the intermediate part. It shows a reservoir for the recovery of leakage through the joints between the casing parts, and communication therefrom through check valves into the working chamber.
Thayer No. 1,883,436, also a prior art reference on the trial, shows a three-part single vane concentric type of absorber with the abutment member secured by means of pins or bolts. The peripheral casing wall of the working chamber is formed in part by a tubular member and the separate abutment. The intermediate part has flat lateral surfaces engaging the flat surfaces of the other parts. The means employed here for securing the parts together is by threaded engagement of the outer or cover part in an outer casing part. This again in this respect is like Stipulated Exhibit C and also the 1922 structure. It shows a non-pressure reservoir chamber between the "walls" of the working chamber parts and the "shell" or outside casing, comparably like Pennington, with check valve control. It discloses no dowel bolts or dowel pins. Automatic replenishment of the working liquid and freedom from leakage are obtained in Thayer.
Neither Johnson nor Thayer anticipates Pennington. Each lacks the integral abutment feature, and it was this feature which plaintiff has pointed ...