Bridge & Plate Constructions Pty Ltd v Mannesmann Demag Pty Ltd

[1988] APO 46

In the Matter of the Patents Act 1952 - and - In the Matter of Patent Application No. 556314 in the Name of BRIDGE & PLATE CONSTRUCTIONS PTY. LTD. - and - In the Matter of opposition thereto under Section 59 by MANNESMANN DEMAG PTY. LTD.

 

DECISION OF A SUPERVISING EXAMINER OF PATENTS:

Background

Application No. 24231/84 was lodged on 6 February, 1984 by Bridge & Plate Constructions Pty. Ltd. for a patent for an invention entitled Single Beam Mounted Cranes. The application was advertised as accepted on 30 October, 1986 and given the serial No. 556314. A notice of opposition was lodged on 27 January, 1987 by Mannesmann Demag Pty. Ltd.; the grounds of opposition were those specified in paragraphs (c) to (i) of sub-section 59(1), although only matters relating to novelty were pursued by the opponent. The matter came to hearing in Canberra on 7 October, 1988; Dr. J. Emmerson QC, Mr. T. Pagone of Counsel and Mr. G. Cowin, patent attorney, appeared for Bridge & Plate Constructions and Mr. G. Turner, patent attorney, appeared for Mannesmann Demag.

The Specification

The specification indicates that the invention relates to overhead single beam travelling cranes, such as travelling bridge beam cranes used in factories. These cranes usually include a support beam extending within the interior of the factory and a crane crab assembly, carriage or trolley, incorporating a hoist, mounted on the support beam for movement therealong.

The specification states that these cranes are usually located as close as possible to the roof of the factory to minimise encroachment into premium factory space and also to maximise the height of lift available to the hoist. In the prior art the crab assemblies have been located on top of the support beam, to the side of the support beam and have been suspended from the support beam; but none of these prior art cranes have been entirely satisfactory in their manner of location within factories. the present invention is directed to an arrangement where the crab assembly, located to the side of the beam, is supported by a chassis located on top of the beam. Claim 1, being the broadest claim defining the invention, is as follows:

A crane, including: a single, elongated support beam arranged to extend generally horizontally during crane operation, the beam having a pair of bearing surfaces extending in the elongated direction of the beam, both of the bearing surfaces being positioned at or adjacent a top of the support beam with one of the bearing surfaces facing upwardly and the other one of the .bearing surfaces facing downwardly; a crane chassis positioned at least substantially above the support beam; a hoist carried by the crane chassis and extending laterally outwardly of the support beam; and, a plurality of rolling wheels all located adjacent the bearing surfaces and mounting the chassis solely on the support beam (as defined herein) to move the chassis along the support beam during crane operation, each rolling wheel having a tread portion in rolling contact with one of the bearing surfaces, the tread portion of at least one said rolling wheel bearing on the upwardly facing bearing surface and the tread portion of at least one other said rolling wheel bearing against the downwardly facing bearing surface so as to prevent the chassis from turning about a longitudinal axis of the support beam off that beam under action of loads applied to the hoist, and the or at least one of the rolling wheels bearing on each of the upwardly and downwardly facing bearing surfaces having a single flange portion only which extends radially outwardly from the respective tread portion and in contact with an edge adjacent the respective bearing surface thereby to guide the tread portion along that surface and thus guide the chassis along the support beam."

On page 3 of the specification the second-last paragraph reads:

"The phrase "mounting the chassis solely on the support beam' is defined herein as meaning that the chassis is mounted only on the single support beam. Thus, the chassis is not also mounted on any additional or auxiliary beam or outrigger rail, spaced from the support beam. Moreover, the chassis is not mounted on any further beam or rail that is carried by or is fixed along the support beam."

In the preferred embodiment of the invention shown in the drawings, the bearing surfaces are embodied by two horizontal flanges projecting on each side of the top of the beam; i.e. integral extensions of the top wall of the beam, projecting outwardly from the side walls. Two rolling wheels on the hoist side of the chassis run on the top surface of one beam flange and two other rolling wheels on the opposite side of the chassis run on the bottom surface of the other beam flange. The torsional forces provided by the weight of the side mounted hoist assembly maintain the rolling wheels in contact with the beam flanges and provide stability for the crab assembly. Radial flanges on the wheels bear directly against the terminal edges of the beam flanges to guide the crab assembly along the beam.

The Evidence

The evidence-in-support comprises declarations by Messrs. V.K. Horton, I. Benesh and V.J. Edwards. The former two are employees of Mannesmann Demag, and Mr. Edwards, now retired, was an engineer with the Department of Industrial Relations Crane, Hoist and Conveyor Section. All three declarants refer to an article from the German magazine VVI-Z which was published in Australia before the priority date of the applicant's claims. From the figures shown in the article it is apparent that it relates to torsion-type beam mounted cranes similar to the applicant's invention. One arrangement, shown in figures 5 and 11, is as follows:

1. An end view of a trapezoidal section bridge beam is shown, with the top wall of the beam projecting past the edges of the side walls, thus forming "flanges".

2. A carriage or chassis is located above the beam and extends past one side of the beam, thus overhanging that side.

3. A hoist is located in the overhanging portion of the carriage and other equipment is located nearer the centre of the carriage.

4. A main carriage support wheel is located underneath and near the centre of the carriage.

5. The support wheel rests on a rail located on top of the flange on the hoist side of the beam.

6. The rail has a generally round cross-section and the support wheel has a convex tread thus making convex- concave contact with the rail.

7. The support wheel has radial flanges on both sides, partially covering the rail.

8. A C-shaped channel member is located directly under the beam flange on the side of the beam opposite to that on which the round rail is located.

9. A guide wheel is attached via an arm member to the side of the carriage opposite the hoist side.

10. The guide wheel fits within the C-shaped channel member, the arrangement thus providing stability for the carriage, i.e. preventing it from rotating about the rail.

The declarants also refer to, as exhibits, two copies of engineering drawings schematically depicting a crane manufactured by Mannesmann Demag for Mercedes Benz (Aust.) Pty. Ltd. The drawings show a box section beam with a trolley thereon; the trolley has radially flanged wheels which run along flanges provided by the bottom wall of the beam.

In his declaration, Mr. Edwards also refers to a copy of two pages of a BHP publication entitled "Monorail Beam Design" which relates to the behaviour of flanges of an I-section beam under action of wheel loads; radially flanged wheels are shown.

The declarants compare the prior art with the claims of Bridge & Plate's specification and generally conclude that most claimed features are disclosed in the VDI article, with any differences being matters of common general knowledge. For example, Mr. Horton states:

"The use of box section beams and flanged trolley wheels has been common general knowledge in the field of crane design for many years prior to the date of Application 556314. It has also been common to have the trolley wheels directly engage a flange provided by a wall of the beam, as clearly illustrated in [the Mannesmann Demag drawings for Mercedes Benz]. For many years prior to the date of Application 556314, it has merely been a designer's choice as to whether to have the wheels directly engage the flange, or to have the wheels engage a rail which reinforces the flange."

The evidence-in-answer comprises declarations from Messrs. J. Pudney, D.S. Robinson, E.J. Burns and R.M. Baird. Each declaration refers to an English translation of the VDI article, and Mr. Pudney also refers to copies of drawings of prior art cranes which show arrangements whereby crab assembly chassis are supported by unflanged wheels running on rails at the top and at the bottom of a box beam.

Mr. Pudney, the inventor, deposes that his crane is "simpler and easier to manufacture and install" than prior art torsion beam cranes, and he states:

"I am able to identify various individual features of the crane which, I am aware, have been separately used on different cranes for many years. However, I am not aware of a crane the same or similar to that torsion beam crane set forth in the presently allowed claims of the Bridge & Plate application, with the particular combination of features defined, as having been disclosed in Australia before the priority date."

He compares his crane with those shown in the VDI article and identifies six differences which he deposes are not "merely the result of designer's choice", and that "crane features are carefully and deliberated selected". For example, on the comment that it has been common practice to have wheels directly engage flanges of a support beam and that it is merely a matter of designer's choice as to whether that support beam of its flanges should be reinforced with a rail, he comments:

"I am aware that in cranes having the chassis hung beneath the support beam that the beam is sometimes composed of a rolled steel section, such as an I beam, and wheels of the chassis bear directly on flanges at the bottom of the beam. [The BHP publication and the opponent's drawings for Mercedes Benz] illustrate two such cranes. However, in my experience that does not apply in respect of the quite different torsion beam crane in which the chassis is located at the top of a single support beam and the hoist is located laterally of the beam. In such cranes it is common for the wheels to run on subsidiary beams or rails fixed to the support beam. This is apparent from the cranes shown in the drawings [accompanying Mr. Pudney's declaration]."

Mr. Robinson, who was Director of the Technical Services Division of the Victorian Department of Labour and Industry (DLI), dealing with inspection of crane installations, generally supports Mr. Pudney's statements. Also in referring to the arrangements in the VDI article, he discusses the C-shaped guide beam and then goes on:

"A guide rail is also attached to the top of the support beam and provides a generally cylindrical rod-like guide along which one or more rolling wheels run. Those wheels have a circumferential groove in which the rod-like guide is received. This groove defines a pair of flanges. It is clear to me that the support beam and additional guide beam and rail are more complex, and bulkier than the simple support beam construction of the crane in the Bridge & Plate application."

Mr. Burns, who was chief Inspector of Lifts and Cranes with the Technical Services Division of DLI, also generally supports Mr. Pudney's statements. Mr. Baird, a consulting engineer experienced in design of overhead travelling cranes, comments on the applicant's crane as follows:

"THAT in considering the crane I was immediately impressed by its simplicity when compared with other cranes of which I was aware. What appeared tome to be innovation was the lack of separate guide rails or beams of similar guide elements and the provision of only two top located, oppositely facing bearing surfaces in the beam for the rolling wheels of the top mounted crane chassis or crab. In analysing the crane design my initial concern was that of the likely steering behaviour of the chassis because of the absence of specific guide elements and minimal number of bearing surfaces for a torsion beam crane. The crane construction places the centre of gravity of the chassis well to one side and probably outside the beam, particularly when the hoist is loaded.' This out of balance causes substantial lateral forces to be exerted at the flanges of the rolling wheels to "steer" the chassis along the support beam. Possible problems that I foresaw arising from such forces were the tendency of the wheels to jam or stick thus preventing further chassis motion along the beam, and failure of the wheel flanges by overstressing or wear or both. In conventional torsion beam cranes known to me at that time these problems were not apparent because of the use of separate guide elements on the support beam providing three bearing surfaces for associated wheels. However, upon inspection of a constructed crane these concerns were alleviated because I discovered that the chassis moved surprisingly freely along the beam and was not subject to the anticipated problems. At that time I was not aware of any crane which incorporated all of the features of the crane."

And on comparing the invention to the VDI disclosure, he comments:

"it is neither apparent nor obvious to me to substitute either the guide beam or guide beam rail or rolling wheels of the cranes in the extract for the support beam and rolling wheel arrangement set forth in the claims of the Bridge and Plate application."

The evidence-in-reply comprises two further declarations of similar content by Messrs. Horton and Benesh. In paragraph 6 of his declaration, Mr. Benesh discusses the use of rails on beams as follows:

"In designing a crane which is to run along a box section beam, the decision as to whether the wheels directly engage a flange of the beam or alternatively a rail supported on the beam, is determined by how accurately the longitudinal extending edges of the flange can be formed. Where the beam consists of a welded structure of metal plates, difficulty is often encountered in accurately aligning the longitudinally extending plates stripped in unequal width as supplied by steel merchants so that there is a continuous edge on both sides along the flange formed against which the guide wheel can engage. If the plates welded in position cannot be accurately located then the designer has the choice of either grinding the longitudinal edges of the flange or alternatively locating a rail on the flange so that the guide wheel can engage the rail in order to prevent excessive wear of wheel flanges."

Construction of Claim 1

Mr. Turner made three significant submissions on the interpretation of claim I of the Bridge & Plate specification.

Firstly, he submitted that the clause "the bearing surfaces being positioned at or adjacent a top of the support beam", in lines 4-6, was broad enough to include an arrangement where the bearing surfaces were spaced from the beam, as would occur for example if a rail was used. He argued that this interpretation was supported by claim 2, which in being appended to claim 1, affects the scope thereof. Claim 2 reads as follows:

"A crane as claimed in claim 1, wherein the support beam includes a pair of spaced apart support flanges each providing at least substantially a respective one of the bearing surfaces."

On this point Dr. Emmerson submitted that the use of "or adjacent" in the said clause in claim 1 was merely to include alternative embodiments where the bearing surfaces were not right on the very top of the beam (e.g. flanges as defined in claim 2 spaced a very short distance below the plane of the top wall of the beam). Also Dr. Emmerson pointed out that the definition statement on page 3 specifically disclaims the use of rails.

Secondly, with regard to the clause in the last 8 lines of claim 1, Mr. Turner submitted that this could include arrangements involving rolling wheels with two flanges on some wheels, only one flange of each such wheel being used for guiding. He argued that this interpretation was supported by claim 10, which reads:

"A crane as claimed in any preceding claim, wherein each rolling wheel is provided with a single flange portion only."

On this point Dr. Emmerson submitted that this part of Claim 1 may be interpreted such that there may be more than one wheel on each bearing surface and that some wheels may have two flanges, but the guiding wheels only have one flange. "A single flange portion only" he submitted means "it has only a single flanged portion, it doesn't have more than one flanged portion."

Thirdly, Mr. Turner referred to claim 17 which reads:

"A crane as claimed in any preceding claim, wherein the crane chassis overlies the support beam so that it moves along the top of that beam during crane operation."

He argued that the existence of this claim suggests that claim 1 may be interpreted to include underhung arrangements of the chassis.

Dr. Emmerson responded by pointing out that claim 1 defines that the chassis is "positioned at least substantially above the support beam", and that claim 17 is simply more specifically defining the position of the chassis.

On each of these three submissions on the interpretation of claim 1 I am sympathetic with Dr. Emmerson's submissions. On the first point I think that "or adjacent" is included in line 5 of claim 1 to allow for the small difference in position between the upwardly facing and downwardly facing surfaces, i.e. the thickness of the beam flanges in the embodiment of the invention (the downward facing surface is not right on the top of the support beam). However, more significantly, the definition statement on page 3 of the specification is clear : claim 1 disclaims the use of rails and the like. On the second point, the words "single' and "only" in the phrase "single flange portion only" have to be given some meaning, and I believe Dr. Emmerson's interpretation is correct; Mr. Turner's version I find to be rather strained to fit the VDI citation, rather than properly interpreted in the light of the invention described, in which no double-flanged wheels were referred to. On the third point I construe claim 1 to include an arrangement where a substantial portion (but perhaps not all) of the chassis is positioned above the beam.

Novelty

Both parties submitted that there were differences between the applicant's claim 1 and the VDI disclosure; the number of differences depended on each party's interpretation of the claim, as discussed above. At the least, Mr. Turner's submission was that "the only difference between this magazine and the invention as claimed is that only one wheel is not flanged". on the other hand Dr. Emmerson submitted that there are at least three differences, one being that the VDI article shows the hoist being above the chassis. I conclude that there are two differences between the applicant's claim 1 and the VDI disclosure, viz:

(a) Use of the round rail and C-shaped channel member in the VDI crane indicates that the chassis not not mounted "solely on the support beam", in accordance with the definition on page 3 of the applicant's specification.

(b) Neither wheel shown in the VDI crane has a "single flange portion only ... in contact with an edge adjacent the respective bearing surface in accordance with the last 8 lines of claim 1.

I do not agree with Mr. Turner's submissions on the number of differences because, as discussed above, I believe that he has misconstrued some parts of claim 1; and I do not agree with Dr.

Emmerson's submission on the hoist feature : the VDI hoist is "carried by the chassis" and "[extends] laterally outwardly of the support beam" in accordance with Bridge & Plate's claim 1.

The matter now to be decided is whether these differences are novelty-conferring features of the invention. Mr. Turner submitted that any differences were merely matters of common general knowledge and he referred me to the decisions in Acme Bedsteads v. Newlands Bros. Ltd (1929) 58 CLR 698, Griffith v. Isaacs (1942) 12 AOJP 739 and Windsurfing International Inc. &.Anor. v. Petit, Borsimex Pty. Ltd. Ors. (1983) 3 IPR 449. Conversely, Dr. Emmerson submitted that the features in the applicant's claim 1 were a patentable combination and he referred me to, inter-alia, the decisions in Willmann v. Petersen (1904) 2 CLR 101, McDonald v. Commissioner (1913) 15 CLR 713 and Martin v. Millwood (1956) 125 RPC 132.

In his submissions on common general knowledge Mr. Turner referred to the evidence on file. Firstly, he suggested that the opponent's drawings for Mercedes Benz and the BHP publication show single-flanged wheels acting directly on the beam. Secondly, he quoted parts of the declarations of Messrs. Pudney, Burns and Robinson which he deduced also indicated that such a feature is common general knowledge.

I comment on these submissions as follows. Firstly, there is no evidence that the drawings for Mercedes Benz and the BHP publication are well-known. In this matter I refer to Luxmoore J. in British Acoustic Films v. Nettlefold Prod. 53 RPC at 250:

"In my judgment it is not sufficient to prove common general knowledge that a particular disclosure is made in an article, or series of articles, in a scientific journal, no matter how wide the circulation of that journal may be, in the absence of any evidence that the disclosure is accepted generally by those who are engaged in the art to which the disclosure relates. A piece of particular knowledge as disclosed in a scientific paper does not become common general knowledge merely because it is widely read, and still less because it is widely circulated. Such a piece of knowledge only becomes general knowledge when it is generally known and accepted without question by the bulk of those who are engaged in the particular art; in other words, when it becomes part of their common stock of knowledge relating to the art."

In this case there is no evidence that the BHP article has been widely read, or even that the drawings for Mercedes Benz were available to the public. Secondly, Mr. Pudney does indicate that he is aware of arrangements with wheels engaging directly with flanges on the bottom of an I-beam, but he emphasises the differences between underhung and torsion cranes. Messrs. Burns and Robinson also emphasise the differences in these types of cranes, and I note firstly that Mr. Burns does not refer to wheels running directly on the beam and secondly that Mr. Robinson does not refer to flanged wheels being known. Thus I conclude that the evidence before me is n6t conclusive proof that features (a) and (b) above can be deemed to be matters of common general knowledge.

Mr. Turner further submitted that the differentiating features were not sufficient to be regarded as novelty-conferring features. In referring to the declarations in the evidence-in- reply, he suggested firstly that "the choice between a rail or a beam boils down to whether or not the longitudinal edges of the beam can be accurately formed; if they can be formed the wheel can directly engage [the beam] flange", and secondly that the flanges on the wheels do not transmit any torsional forces, this happens only through the tread portions of the wheels, therefore the flanged wheels in the invention perform a function no different to that performed by non-flanged prior art wheels.

For the applicant, Dr. Emmerson argued that the whole combination of features defined by claim 1 is not anticipated, and that the opponent was creating an "impermissible mosaic" of the prior art. He submitted that the VDI crane is not concerned with the space-saving problem of the present invention, he stated:

"Both the problem and the conceptual solution in the VDI case are quite different from those in the present case. The VDI specification is in important respects unclear about how it really envisages that the wheel and the guidance system will work; which is not too surprising because it ain't actually concerned with these matters, it's concerned with other problems"

In this matter I think it is significant that the carriage support and guidance mechanisms in the VDI cranes are different from those in the applicant's invention. The rail and main support wheel in the VDI crane appear to provide most of the support and guidance functions, the guide wheel being provided to balance the carriage; whereas in the Bridge & Plate crane, the support and guidance functions are spread across all the wheels running on the beam flanges. As indicated above, I do not think the opponent has provided enough evidence to prove that differentiating features (a) and (b) are matters of common general knowledge; however, even if this had been proven, I would still be reluctant to refuse claim 1 of the applicant's specification since it does define a patentable combination of integers. I am satisfied that differentiating features (a) and (b) are essential features of the invention, are part of a patentable combination and contribute to the working of the crane. Also there is some merit in the invention, as indicated by Mr. Baird. Claim 1 thus satisfies the Griffith & Isaacs test for novelty as well as being directed to a patentable combination. The decision in British Westinghouse Electric and Manufacturing Co. Ltd. v. Braulik [19101 27 RPC 209 is pertinent; at page 230 Fletcher Moulton L.J. stated;

"I confess that I view with suspicion arguments to the effect that a new combination, bringing with it new and important consequences in the shape of practical machines, is not an invention because, when it has once been established, it is easy to show how it might be arrived at by starting from something known, and taking a series of apparently easy steps. This ex post facto analysis of invention is unfair to the inventors and, in my opinion, it is not countenanced by English Patent Law."

Finally, in comparing the circumstances in this case with those in Windsurfer supra, I believe that a clear distinction can be made. In that case, the Darby article, which was cited against the claim, was very close to a complete prior publication. The article included a note, and, although the Court decided the note was not clear enough to regard the article as a prior publication, when the note was interpreted in the light of common general knowledge to give it a clear meaning, the Court decided that this feature did 'not involve any ingenuity or inventive step within the doctrine in Griffith v. Isaacs-. In the present case there is no equivalent to the note in the Darby article; i.e. there is no suggestion at all in the VDI article that the wheels may run directly on the beam or that the wheels may have single flanges.

Conclusion

I have found that the opposition has failed on all grounds and that there is no lawful ground of objection to the application and complete specification. I direct therefore that the application and complete specification proceed to sealing, subject to any appeal.

I award costs against the opponent.

(J.I. WELSH)

Supervising Examiner of Patents

5 DEC 1988

Patent attorneys for the applicant: Phillips Ormonde & Fitzpatrick, Melbourne

Patent attorneys for the opponent Spruson & Ferguson, Sydney