Hensley Equipment Company v. Esco Corporation

• Decision Date: 03 March 1967
• Docket Number: No. 20599.,20599.
• Citation: 375 F.2d 432
• Parties: HENSLEY EQUIPMENT COMPANY, Inc., Appellant, v. ESCO CORPORATION, Appellee.
• Court: U.S. Court of Appeals — Ninth Circuit

375 F.2d 432 (1967)

HENSLEY EQUIPMENT COMPANY, Inc., Appellant, v. ESCO CORPORATION, Appellee.

No. 20599.

United States Court of Appeals Ninth Circuit.

March 3, 1967.

Thomas O. Herbert, Flehr & Swain (Flehr, Hohbach, Test, Albritton & Herbert), San Francisco, Cal., for appellant.

Edward J. Ruff, David Van Hoesen, Thelen, Marrin, Johnson & Bridges, San Francisco, Cal., Jerome F. Fallon, Dawson, Tilton, Fallon, Lungmus & Alexander, Chicago, Ill., for appellee.

Before HAMLEY and ELY, Circuit Judges, and MATHES, District Judge.

HAMLEY, Circuit Judge.

Esco Corporation (Esco), owner of Baer Patent No. 2,483,032 (Baer), brought this patent infringement suit against Hensley Equipment Company, Inc. (Hensley), manufacturer and seller of the accused apparatus. The Baer patent is a combination patent describing a mechanical device known in the heavy construction industry as a two-part excavating tooth.

Esco alleged that Hensley had infringed claims 5, 8 and 9 of Baer. Claim 5 describes the overall combination of the two parts of an excavating tooth. One part is an "adapter," which is secured to the lip of a piece of excavating equipment. The other part is a replaceable "wear point" which fits on the adapter and provides the actual cutting edge of the overall tooth. Claims 8 and 9 pertain only to the replaceable wear point. In addition to denying infringement, Hensley defended on the grounds that claims 5, 8 and 9 of Baer are invalid and that, by reason of misuse, Esco is estopped from claiming infringement.

The trial court found and concluded that claim 5 of Baer was not infringed. Therefore, without determining the validity of claim 5, the court denied Esco any relief as to that claim. The trial court further found and concluded that claims 8 and 9 of Baer are valid, there was no misuse thereof, and Hensley infringed those claims. A judgment to this effect was entered, enjoining Hensley's further infringement of claims 8 and 9, and referring the matter of damages to a special master. The trial court's extensive memorandum opinion and order is reported sub nom., Esco Corporation v. Hensley Equipment Company, Inc., 265 F.Supp. 863.

Hensley appeals, arguing that the trial court erred both as to the validity and infringement of claims 8 and 9 of Baer.¹ We will first deal with the question of the validity of claim 8.

The validity of a patent is dependent upon whether the described apparatus meets three explicit statutory conditions, namely: novelty and utility as defined in 35 U.S.C. §§ 101, 102 (1964), and nonobviousness, as defined in 35 U.S.C. § 103 (1964). See Graham v. John Deere Co. of Kansas City, 383 U. S. 1, 12, 86 S.Ct. 684, 15 L.Ed.2d 545. The trial court found and concluded that claims 8 and 9 of the Baer patent meet all three of these tests. Hensley contends that the trial court erred in concluding that these claims are novel and nonobvious.

Claim 8 describes a combination of twelve mechanical elements, each old in the art.² In determining whether this combination is novel and nonobvious, the parties and the trial court limited themselves, primarily, to a consideration of three basic features of claim 8, involving five elements. These are: (1) tongues which, Esco contends and the trial court held, must extend rearwardly from the wear point, designed to fit into recesses in the Baer adapter (elements 11 and 12 of claim 8); (2) a spike portion "of relatively heavy section" which, Esco asserts and the trial court held, refers to the upper portion of the wear point, such portion being heavy as compared to the side and bottom walls of the wear point (element 5 of claim 8); and (3) spacing between parts of the wear point and the adapter (elements 9 and 10 of claim 8).

Before the novelty and nonobviousness of the combination of these three features of claim 8 can be considered, it is necessary to resolve two questions raised concerning the construction of claim 8 as it relates to these features.

Hensley argues that Esco has itself construed the reference to tongues in elements 11 and 12 of claim 8 as not limited to tongues extending rearwardly from the wear point, but as also including tongues extending forwardly from the adapter, designed to fit recesses in the wear point. In support of this view, Hensley points out that Esco manufactured and sold wear points, bearing the Baer patent number, which were equipped with recesses in the wear point to receive tongues extending from a cooperating adapter.

Elements 11 and 12 of claim 8 explicitly provide that the tongues are to be on the wear point. They are also so shown in the patent drawings, and are so described in the patent specifications. Esco justifies the Baer patent marking on its manufactured wear points equipped with recesses as being in accordance with claim 5 of that patent. That claim does not expressly refer to tongues, but does call for "additional means stabilizing the tooth point relative to the adapter in the direction laterally to the nose." We think that forwardly extending tongues on a Baer adapter would be consistent with that provision.

It follows that Esco's use of the Baer patent number on such a two-part device did not constitute an interpretation of claim 8 as permitting recesses on the wear point to receive tongues on the adapter. We conclude that the tongues contemplated by claim 8 must extend rearwardly from the wear point.

The "spike portion of relatively heavy section," described in element 5 of claim 8, was referred to by the trial court as "the heavy upper spike portion of the point," meaning that the upper portion of the wear point is heavy as compared to the other walls of the wear point. Hensley argues that claim 8 does not specify that it is the upper portion of the spike which is to be "relatively heavy." Moreover, Hensley contends, claim 8 does not state that the spike portion is heavy as compared to the other walls of the Baer wear point.

It is true that claim 8 does not expressly state that the term "spike portion" is the upper portion of the wear point. In the specification, however, the "spike portion" and the "housing portion" are referenced to patent drawings which show that the spike portion is the upper portion of the Baer wear point, as described in claim 8. It is proper to resort to the specification for the purpose of clarifying the reference to the "spike portion" in claim 8, since in this regard the specification is not in conflict with that claim.

Claim 8, standing alone, does not substantiate the trial court's view that the spike portion is to be heavy as compared to the other walls of the Baer wear point. Nor does the specification say anything regarding the heaviness of the spike portion. However, since the patent drawings show the upper spike portion to be relatively heavier than the bottom portion of the Baer wear point, we think the trial court was justified in construing the quoted language of claim 8 as referring to the weight of the upper spike portion in comparison to the weight of the other walls of the claim 8 wear point.

For the reasons stated above, we accept, as accurate, the trial court's construction of those elements of claim 8 which describe the tongues and spike portion of the wear point.

At the trial, Hensley took the position that Mekeel Patent No. 1,845,677 (Mekeel '677), issued on February 16, 1932, is the most analogous prior art.³ In view of Hensley's position in this regard, the parties and the court seem to have proceeded at the trial on the theory that the question of whether the combination of the three features of claim 8, referred to above, is novel and nonobvious, could best be determined by comparing those features with the assertedly similar features of Mekeel '677. The parties have proceeded similarly on this appeal.

The Mekeel '677 patent does not, as in claim 8 of Baer, show a wear point with rearwardly extending tongues. Instead, the patent drawings and specification show that there are recesses at the rear of the Mekeel wear point, which cooperate with mating tongues on the Mekeel adapter.⁴ Hensley argues, however, that the teaching of Mekeel '677 concerning tongues is "far broader" than as depicted in the Mekeel patent drawings.

In support of this assertion, Hensley refers to language in the Mekeel '677 specification regarding a modification of the invention. According to this modification, tongues formed in "one member" of the assembly project beyond that member to engage in recesses in the "other member" of the assembly. It is further stated in this part of the Mekeel '677 specification that this modification is "illustrated" in the patent drawings. Hensley argues from this language that Mekeel places no special significance on whether the tongues extend rearwardly from the wear point, or forwardly from the adapter.

We think that if Mekeel '677 contemplated rearwardly extending tongues the patentor would have employed more explicit language than can be gleaned from the references in the specification to "one member" and "illustrated." This is especially so in light of the additional...