Opinion ID: 771385
Heading Depth: 3
Heading Rank: 2

Heading: Prosecution History of the Patents at Issue

Text: 113 1. The Stoll patent application was filed in the United States as the U.S. counterpart of a German patent application. As filed, claim 1 of the Stoll patent initially read: 114
115 said motor being operable by a pressure medium and comprising a tubular part connectible to a source of the pressure medium, 116 a piston which is slidable in said tubular part and which has sealing means at each end for [w]iping engagement with an internal surface of the tubular part and so as to form a seal for the pressure medium, 117 and a driven assembly which is slidable on the tubular part and which has means at each end for [w]iping engagement with an external surface of the tubular part, 118 the piston and the driven assembly each carrying a drive magnet arrangement in the form of a hollow cylindrical assembly, 119 each magnet arrangement having radial play relative to the adjacent surface of the tubular part, 120 and surfaces of the magnet arrangements which face the tubular part being closely adjacent to the respective surfaces of the tubular part. 121 The original application also included two dependent claims of relevance, claims 4 and 8: 122 4. A linear motor according to any of claims 1 to 3, wherein the sealing means of the piston comprise sealing rings and the piston is provided with sliding guide rings near the sealing rings. 123 8. A linear motor according to any of the preceding claims wherein the driven assembly is provided with a sleeve made of a magentisable material, which encircles the hollow cylindrical assembly of the magnet arrangement. 124 (Emphasis added.) 125 In the first Office Action, the patent examiner rejected all twelve original claims, and cited three patents as references believed pertinent. Claims 1-12 were rejected under 35 U.S.C. § 112, ¶ 1, because the exact method of operation is unclear. Is [the] device a true motor or magnetic clutch? In addition, claims 4-12 were rejected under 35 U.S.C. § 112, ¶ 2, because they were improperly multiply dependent. 126 In response, Stoll amended some claims, including claim 1, and canceled others, including claims 4 and 8. Claim 1 was amended to recite plural guide ring means . . . and first sealing rings located axially outside said guide rings on the piston and to recite a cylindrical sleeve made of a magnetizable material. In the remarks accompanying the amendments, Stoll stated that [e]ach of the claims now present in this application has been reviewed for compliance with the provisions of Title 35 USC 112. Accordingly, further consideration of these claims, particularly with respect to the provisions of Title 35 USC 112, is respectfully solicited. 127 When Stoll submitted this amendment, he also made two German patents of record in the application, No. 27,37,924 and No. 19,82,379. Stoll had received these patents in the first office action in the corresponding German application. Stoll argued in the remarks accompanying the amendment that the claims now present in th[e] application are distinguishable over these references. Stoll stated that i[t] is clear that neither of these two references discloses the use of structure preventing the interference by impurities located inside the tube and on the outside of the tube while the arrangement is moved along the tube. 128 After considering this response, the examiner allowed the amended claims, requesting that all references to linear motors be deleted from the specification, because this phrase connotes a different device having different operational characteristics. 129 2. The relevant portion of the Carroll patent's prosecution history is its reexamination. Before reexamination, claim 1 of the Carroll patent read as follows: 1. A device for moving articles comprising 130 a cylinder of non-ferrous material, 131 a piston including a permanent magnet having a pole-piece on each axial side thereof, 132 a body disposed outside and adjacent to said cylinder, said body including a permanent magnet which substantially surrounds the cylinder, there being a pole piece on each axial side of the permanent magnet included in said body, and 133 means for controlling the admission of pressure fluid into the cylinder and exhaust of fluid from the cylinder for moving the piston in the cylinder, 134 the attractive forces between the permanent magnets being such that movement of the piston causes corresponding movement of the body below a predetermined load on the body and such that above said predetermined load movement of the piston does not cause corresponding movement of the body. 135 Original Carroll patent, col. 4, ll. 4-19 (paragraphing added). This claim did not recite the sealing rings disclosed in the specification. 136 Carroll requested reexamination on March 18, 1988, citing German Patent No. 1,982,379, which was not of record in the Carroll patent's prosecution history. In his request for reexamination, Carroll asserted that the German patent presented a substantial new question of patentability because the Patent Office may find the German patent, in combination with the other references which were cited during prosecution of the Carroll patent[,] . . . to disclose several of the primary structural features of the device defined by Claim 1. 137 The German patent described rodless cylinders having several of the features of the device described in the Carroll patent, including a pair of sealing rings. The Patent Office granted Carroll's request for reexamination, finding that the German patent discloses an article transport device which is movable in response to a hydraulically operated magnetic piston, which is a feature that was not found by the Examiner during the prosecution of the Carroll patent. 138 During reexamination, Carroll canceled claim 1 and added claim 9, which explicitly recites a pair of resilient sealing rings situated near opposite axial ends of the central mounting member and engaging the cylinder to effect a fluid-tight seal therewith. In the remarks accompanying the amendment, Carroll argued that the now-amended claims 5 more clearly and more specifically define the features of the patentee's invention that distinguish over the art of record, including the German patent cited in the request for reexamination. Carroll also noted that the structure now described in claim 9 was not disclosed in the art of record. Carroll further stated that the particular structure of the inner piston and outer body now specifically set forth in new claim 9 is not taught or suggested by the German patent, particularly noting the recitation of the placement and plurality of magnets for both the piston and outer body and the recitation of resilient materials and cushion materials on the ends of the piston. 139 The examiner allowed the amended claims, stating that the prior art does not teach or render obvious the claimed combination which includes the plurality of magnets, end members, and cushion members in the claimed relationship.