IN THE HIGH COURT OF AUSTRALIA —-HILL S-HOI ST. $ (MANUFACTURING) PROPRIEFARY LIMITED REASONS FOR JUDGMENT /f 2. Judgment delivered at__ggpeey —— —— ___ on... SHORSDAY y-17th-DECEMBER-1964._ 'A. C. Brooks, Government Printer, Melbourne ©.7639/60 mn Appeal in each ease dismissed with costs. Cross appeal dismissed. We (2 appeaLs) Ve DAVID A (2 appeals) The plaintiff, the proprietor of two letters patent, ono dated 25th July 1955, and numbered 213610, and the other dated 15th May 1957, and numbered 221120, sued the defendant in this Court for infringenent of each of the letters patent. Both were for improvements in and relating to rotary clothes hoists. There is now no question as to the infringe- ment by the defendants but the validity of the letters patent is challenged. The justice who hearé the case found that in the case of each of the letters what was claimed as the inventive step was obvious anc that for that reason each of the letters patent wes invalid. The sole question in this appeal is whether or not the processes of manufacture claimed in the specifications of the letters patent laeked novelty or were obvious. : His Honour in his judgsent fully and adequately described the nature of the retary clothes hoists which the appellant had for some time been engaged in manufacturing prior to the grant of the firet of these letters patent. His Honour fully ceseribed the experience which the appellant had had with its retary clothes hoists, anc the problems whieh thair use had developed. He also fully deseribed the invention claimed by the appellant in each of the letters patent. There is no neod for me to repeat any of these descriptions which I adopt for the purposes of thia judgment. I turn firet to the question of the validity of the letters patent No. 213610. The appellant, in common, no doubt, with other manufacturers of like rotary clothes hoists, hac found that the absence of any positive sechanism for retracting the moving ecoluan of the hoist, or as I will bereafter 2. Gall it, the secondary member, which carried the radial aras with their connecting clothes iines, was not merely inconvenient but in the use of the clothes line led in some instances to injury and in many more to dissatisfaction. To rely merely on the force of gravity te return the secondary meaber when by the use of the handle the threaded member was wound down, had proved in any event inadequate and in many instances dangerous. The cure or remedy for this disadvantage was quite obvious. It was to provide some positive connection betwoon the threaded menber and the secandery member so that there would be a positive retraction of that sember when the threaded member wae wound down. MeKirdy, another manufacturer of clothes hoists, had provided this physieal connestion by means of « bolt: he had eovered this feature by letters patent prior to the appellant's grant No. 213610. The appellant asde the connection by extending the threaded member in the form of a hook which, bearing on the lever end of the secondary member, drew it down with the threaded member. This was the subject of the letters patent with whieh I az presently dealing. It was, of course, necessary for the secondary meuber to be free te rotate. MeKirdy allowed this by so distancing the head of the belt in the top of the threaded menber that the bottom of the secondary meaber through which the bolt was passed was free to rotate in the gap left between it and the top of the threaded member. The plaintiff provided the freedom of movement of the secondary meuber by having the hooked ead of the threaded member inserted inte the conteal bottom of the secondary member, the top of the threaded member also being conical, thus allowing the secondary meaber to rotate around the stem of the hook whilst providing the hook with a bearing surface when it was required te effect the retraction of the secondary member. 'The use of the interacting coniesl faces was a well- known method of ensuring a self-contring effect. 3. There is no question but that the appellant's method of making a physical connection between the threaded member amd the secondary member has considerable advantages, both fwom the aspect of manufacture and from that of ease of agsenbdly. It avoided the disadvantage of HeKirdy's solution whieh could require maintenance involving the disassembly of tke clothes hoist by reason of the loosening of the bolt issserted inte the head of the threaded member caused by the rotation of the secondary member. But although useful and effective, and having the advantages of whieh I have spoken, tine question remains as to whether or not the appellant's s@lution in providing the hook extending fros the threaded mesbder and intruding into the conical bottom of the seeondary member as the means of effecting a physical connvetion between tine two wombers, involwed an inventive step. As I bave said, tine need fer such a physi¢el connection as a means of over- coming the knovn difficulty in effecting the retraction of the S@eondary member vas obvious. Was the provision of the heok am obvious seans of aaking the connection? To support the ¢@eatention that there vas an inventive step it is not enough that the appellant's solution may not leap imuediately to mand but needs to be tho result of thought and the application o@ some skill. er on the other hand is it enough to deny tine existence of such a step that by the use of hindsight one can seo how simple that solution was. Gne must be very eareful that hindsight dees not inject the demonstrated sanplicity of the solution inte the mind or knowledge of the person faced with the wmresolved problen. That the solution of the appellant was superior to that of McKirdy is, I think, @Rear enough. But was it any sore than the result of better é@sign or a higher order of workshop work than the known wetheds of making a physical ¢onneetion between the two members? Gan it be said that a person of reasonable competence arad with knowledge of general engineering principles and skilis &. end @f the structural and operating requiresents of rotary Glothes hoists faced with this proble= would have found its solution obvious? Having given the matter a great deal of eonsAderation and although inevitably impressed by the advantages which the appeliant's method of previding for the retraetion of the secondary member undoubtedly has, 1 have come to the clear conclusion that the solution would be obvious and that there was no inventive step involved in the provision of the heok extension of the threaded member intruded through the wonical bottom of the secondary colum. To my mind, it wes mo wore than a competent workshop iuprovement of a very useful kind. Consequently, in my opinion, His Roneur was correct in finding that for want of an inventive step none of the @lains sade in the specification to letters patent nuabered 213610 were valid. It is therefore unnecessary for me to consider whether or not this invention of the appellent lacked novelty because of McKirdy's earlier specification to which I have referred. T turn now to the svgond of the letters patent Ho. 221120. However, in thie instanes, unlike that of the first letters patent, the problem which the sppellant faced was not exactly common to all who made rotary clothes hoists or if the problem existed at all in the case of hoists made by sous others it was not so eeute as to have called, in a commercial senme, for any solution. The plaintiff was faced with the diffieulty that whers the arms attached te the secondary meaber rotated, or perimaps werely vibrated, under the influence of the wind when in wse and elevated, rotation was commmicated te the threaded wouter, vith the result that that member began to retire through the thread in the crow: wheel, thus causing the clothes line to Wwe lowered. Se That there wore only two ways of preventing this result was obvious and what those vays were was obvicus. f leave on one side the third possibility which sone manufacturers had adopted of providing for some lecking device which prevented the rotation of the secondary member, This was in a mechanical sense a solution: bat in fact it denied to the user of the hoist one of the prineipal advantages of this type of clothes line because the rotation of the line is related to the speed of the drying of the elothes. The two possible courses were, firstly, to reduee the piteh of the thread on the threaded member, that is to say, to flatten it, thereby inereasing the frictional elesent in the passage of that meaber through the thread in the crown wheel. This, of course, would reduce the speed with whieh the secondary menber could be elevated by any given number of turns of the crown wheel by means of the handle. Secondly, to introduce frictional resistance te the rotation of the crown wheel at sone other point than the point where the threaded member passed through it. The point at whieh to introduce this friction vas quite cobviews. Tt was an indispensable element in the apparatus thet there should be a bearing surface against which the crow wheel could thrust when rotated so that the threaded member would be elevated by passing through the threaded centre of the crown wheel. It was alse necessary to have a surface to carry the vertical lead of the secondary mewber which would include the load imposed by the clothes on the lines and would be communicated through the threaded member. This thrust bearing surface as a point for the introduction of friction was obvious. The appellant was unwilling to aceept the first of the two possible alternative methods though it wuld seem some other manufacturers of rotary clothes heists may have dene seo. He was wnwilling te reduce the piteh of the thread on the threaded member and thus forfeit the advantage of a high rate 6. of elevation of the secondary member. He vanted to minimise the number of turns of the handle which would be necessary to raise the secondary member to its full height. Por the appellant, therefore, only one of the solutions was acceptable. To my mind, it wae thus obviews that te secure the desired result he must introduce friction at the bearing surface of the thrust bearing supporting the crown whwel. It is quite true, ag the appellant's counsel insisted, that these ost familiar vith rotary clothes hoists would have been unwilling to have introdwed or to have friction at that point. They would have been wavilling to do so because they would have regarded the minimising of friction at that point as the desiderates. But I do not think that in this ease that is a very relevant circumstance. These whe would have refused to introduce friction at the point of the thrust bearing surface, walike the appellant, may well have been prepared to ageept the redustion in the piteh of the threaded member as their solution. The appellant's precise solution was to make the surface of the thrust bearing conieal rather than the flat surface which was in general use. ly adopting a conical face for the thrust bearing the appellant enabled himself to adjust the slope or angle of that surface so as to satisfy his two requiresents: om the one hand, the need to resist rotation of the threaded member when it was desired to maintain the height of the secondary mouber, and on the other band, the need to have relative ease of rotation when it was sought te elevate thet momber. This, of course, was a matter of compromise and balanes. The appellant found, by simple trial and error, that by a combination of the slope or angle of the conieal surface of the thrust beering, the nature of the material, and the fineness of the casting, used for the thrust bearing, he could obtain the desired result: enough friction to arrest the tendeney of the threaded member to come down under the influence of the rotating or vibrating secondary auaber, and a sufficient absence of friction to enable the user of the apparatus to elevate the secondary member without undue effort. Bere again the sppellant has achieved « singularly useful alteration to the apparatus of a rotary clothes hoist. He bas solved a problem which, although in the present cireun- stanees peculiar to clothes hoists of his manufacture in that these retain the relative high piteh of the threaded member, e@ould emerge in wider cireusstances. Thess advantages of the appellant's solution were obtained without any significant complication in manufacturing procedures. But in ay opinion there was no inventive step involved in the introduetion of the thrust bearing with a ¢onical surface. Counsel for the appellant pointed out that hitherto the use of a conical face as a frictional surfaces had mot proved suecessful when used in other forms of apparatus, as for example, in a motor ear eluteh, or as a braking surface, because it proved unduly severe or not sufficiently matageable. But the need for intredueing frietion to solve the instant probles was obvious. That a conical face would provide greater frictional resistance was obvious. That the variation of the slope or angle of the cone would produce warying degrees of resistance was also obvious. im wy opinion, ia Honour was ¢errect in his conclusion that the elaine of the specification He. 221120 were all invalid. Im wy opinion, the appeal should be dismissed. The ¢rose appeal of the respondent was not proeseded with and should therefore be disuissed. I agree that the appeal be dismissed. TI am not satisfied that the learned trial Judge erred in his conclusions on any issue of fact raised at the trial and that his application of the law was entirely right. t agree in the judgment of the Chief Justice ami I have nothing to adds We DALLA Ao I am of the opinion that these appeals and @rosseappeals should be dismissed and { have nothing to add to the reasons of the chief Justice. JOUDGHENE satiu © HILLS HOISTS (MANUFACTURING) PROPRIETARY LIMITED Ve DAVID AND ANOTHER MENZIES Js HILLS HOLSTS (MANUFACTURING) PROPRIBTARY LIMITED Ve DAVID AND ANOTHER I have had the advantage of reading the gudgnent of the Chief Justice and, for the reasons which he gives, I think both appeais should be dismissed.