3. The Prior Art -- The Manby Patent
62. The Manby patent (Defs.' Ex. B6) entitled "Improvements in or relating to Anti-Friction Bearings" is substantially identical to the '128 patent. The Manby patent specification was published on May 16, 1962 (approximately 13 years before the filing of the Geffner application), based upon a British patent application (Serial No. 7072/57) filed on March 4, 1957. Defs.' Ex. B6.
63. The Manby patent specification (or "Manby"), like the Geffner '128 patent, discloses a number of constructions of an antifriction bearing which permits both relative linear and relative turning movement between the bearing assembly and a shaft. Defs.' Ex. B6 (page 1, lines 10-16 of the Manby patent). In this regard, Manby discloses at least two related embodiments found in Figures 1-4 and Figures 5-6. The Court first will describe those features common to both embodiments, and then will turn to discuss the distinctions indigenous to each.
64. With reference to Figures 3 and 5 of Manby, each embodiment includes a hollow cylindrically-shaped bearing cage (items 12 and 26 respectively) positioned inside the outer race and rotatable therein. Each cage contains a plurality of ball bearings. The bearing cage facilitates the linear and rotary motion of the outer race with respect to the inner race.
65. The bearing cage (or retainer) includes a plurality of trackways (items 14 and 27 respectively) which contain the ball bearings. See below. The cage 12 has a thickness which is less than the ball bearing diameter. Each trackway is opened at the radial top and bottom so that the ball bearings may extend simultaneously from the outer and inner surfaces of the cage. As is the case with the '128 patent, linear movement of the ball bearings through the trackways facilitates linear movement of the outer race with respect to the inner race.
[SEE Fig. 3 IN ORIGINAL]
[SEE Fig. 5 IN ORIGINAL]
66. With reference to the embodiments shown in Figures 1 and 6 below, the outer race (items 11 and 30 respectively) are generally cylindrically-shaped and contain an inner and outer surface. Located on the inner surface are a plurality of bearing lands (items 16 and 29 respectively) (described as "bearing faces" in Manby) which extend longitudinally a length which is less than the length of the outer race. A plurality of recesses (items 17 and 31 respectively) (described as "depressions" in Manby) are positioned between the bearing lands and extend longitudinally along the inner surface of the outer race. Like the bearing lands ("bearing faces"), the longitudinal length of the recesses ("depressions") is less than the length of the outer race. Positioned at the ends of the bearing lands and recesses are first and second circular recesses (called "peripheral depressions" in Manby).
[SEE Fig. 1 IN ORIGINAL]
[SEE Fig. 6 IN ORIGINAL]
67. As stated above, linear movement of the outer race is provided by a continuous movement of the ball bearings through the trackways. Ball bearings in one trackway simultaneously engage both the bearing land ("bearing face") of the outer surface and the smooth surface of the inner race (called a "shaft") and move together in one direction. Concurrently, ball bearings in an adjacent trackway travel in the opposite direction and through a recess ("depression"). While in the recess, the ball bearings engage only one of the inner and outer races.
68. In the first embodiment as shown in Figures 1 and 3 of Manby, the trackways 14 are equally spaced apart around the bearing axis (Manby, page 5, lines 98-100) and are connected at their ends by semicircular-shaped returns 15 ("curved track end portions") to form a single closed zig-zag circuit around the periphery of the cage. (See the bearing cage of Figure 3 above.) In this arrangement, the interconnections between the trackways allow for a continuous stream of ball bearings to circulate completely around the cage periphery. The returns are aligned with the first and second circular recesses ("peripheral depressions" in Manby). Thus, when the ball bearings enter any one of the returns, the ball bearings engage only one of the race members.
69. As previously stated, continuous movement of ball bearings through the trackways facilitates linear movement of the race member. The returns allow ball bearings in one trackway to move into an adjacent trackway. Since ball bearings in one trackway travel in an opposite direction of ball bearings in an adjacent trackway, the returns allow for a continuous stream of ball bearings through any one trackway.
70. The relative widths of the bearing lands (B) (i.e., "bearing faces"), the recesses (C) (i.e., "depressions") and the adjacent trackways (A) are described. On page 2 beginning at line 102, Manby sets forth:
The circumferential width of the bearing faces 16 is made slightly less than the width of the depressions 17 so that as measured peripherally the distance between the contact points of balls 13 in adjacent trackways is very slightly greater than the width of each bearing surface 16.
Defs.' Ex. B6 (page 2, lines 102-108 of Manby patent).
71. In other words, the arcuate width of each recess (C) is greater than the arcuate width of each bearing land (B), and the width between adjacent trackways (A) is greater than the arcuate width of the bearing lands (B). Using the Geffner scheme, C > B and A > B.
72. Further, the number of longitudinal trackways in the cage of the embodiment of Figures 1-4 is twice the number of longitudinal bearing faces (bearing lands) on the outer race. Moreover, the trackways and bearing faces are spaced equally apart around the bearing axis. Defs.' Ex. B6 (page 5, lines 94-100 of the Manby patent). This is to prevent jamming or the formation of a "critical setting," the situation in which ball bearings in adjacent pathways simultaneously engage both the inner race and the bearing land. Id. (page 2, lines 123-130 and page 3, lines 1-28 of Manby patent).
73. As mentioned above, an alternative form of construction which illustrates "a further method of avoiding critical settings" is shown in Figures 5-6 and discussed in principle on page 3, lines 69-110 of the Manby patent. Here, adjacent pairs of trackways are connected by returns to form a plurality of closed loop tracks (or "circuits"), as is the case in the '128 patent. (See Figure 5 of Manby above.) In one trackway, ball bearings travel in one direction simultaneously engaging both the bearing land (or "bearing face") and the inner race. Ball bearings in the other trackway travel in the opposite direction and through a recess ("depression") of the outer race.
74. In this regard, Manby indicates that the modified retainer or bearing cage 26 of Figure 5 is the same as the retainer or bearing cage 12 of Figures 1 and 3 with the exception that, instead of joining the ends of the trackways together to form a single closed zig-zag arrangement, the trackways are joined at each end to form a plurality of closed circuits. Specifically, Manby on page 3, lines 72-86 states:
Fig. 5 shows a modified bearing cage 26 having trackways 27 corresponding to the trackways 14 except for the fact that they are connected in adjacent pairs with those of each pair joined at both ends by arcuate track end portions 28. Thus the cage provides a succession of separate closed circuits for the balls arranged around the circumference of the cage. As before the balls in each closed circuit run along trackways 27 for linear motion and while in one of the trackways they engage a bearing surface 29 on an outer race 30, see Fig. 6, and run freely in the other trackways opposite a depression 31 in the race.
Defs.' Ex. B6 (page 3, lines 72-86 of Manby patent) (emphasis added).
75. This embodiment is described as permitting linear and rotary motion of the outer race member in the same manner as the bearing of the first embodiment, but with a set of balls running around a separate closed loop track (or "circuit") as opposed to a zig-zag succession of interconnected trackways. In other words, the bearing cage of the second embodiment is identical to that of the first embodiment except for the manner in which the pathways are interconnected by the returns.
76. The recesses ("depressions") are further described as having a width slightly greater than the width of the closed loop track (C > A). In particular, beginning on page 3, line 86, Manby recites:
The depressions 31 are each of a width slightly greater than the distance between the contact points of balls in adjacent trackways.