The opinion of the court was delivered by: SCHOONMAKER
This is a patent suit involving claims 8, 9, 12, 14, 15, 16, and 17 of Peik Patent No. 1,953,566, dated April 3, 1934, for a blasting machine of a centrifugal type, intended for the projecting of abradant particles such as sand, shot or other grits. The invention is said to rest in the directional properties of the machine, in that it is possible to project the blast over a desired limited zone. There is no limitation as to the type of work to be done by the projected blast.
Peik, in his patent application, gives the following general description of his invention (Patent 1,953,566, page 1, lines 1 to 62 inc.):
'I provide a rotatable head having a central opening with a passage or passages extending from such opening to the periphery of the wheel, which passages are preferably spirals extending outwardly or rearwardly with respect to the direction of rotation. Within the central opening I place a normally stationary container, which container has a passage of peripheral length through which blast particles may be fed from the container to the passage or passages in the head. I employ an impeller within the container and feed blast particles to such impeller, whereby uniform feeding of the blast particles to the rotatable head is obtained. Since the feeding of blast particles form the container to the rotatable head takes place only over a limited range, the discharge is correspondingly limited. I make provision for adjusting the orientation of the container so that the orientation of the discharge zone may be likewise varied, and I also provide for adjusting the peripheral length of the opening through which the blast particles are supplied so that the annular length of discharge zone may be likewise controlled.
'I have found that in order to get the best results it is highly desirable to use passages of generally spiral form in the head, which passages serve to feed the particles at rapidly increasing velocity toward the periphery of the wheel. I there provide discharge or impact surfaces against which the particles strike and from which they rebound to be discharged from the head. This arrangement gives a nicety of control which is ordinarily very difficult if not impossible to obtain and insures highly efficient blasting.'
The claims of the patent in suit relate to the directional control features of the invention.
Claim 16 is cited as a typical claim. It is as follows:
'16. A blasting machine comprising a rotatable head having a central opening, a passage extending from such central opening to the periphery of the head, a normally stationary container within the central opening, said container having a passage of limited peripheral length through which blast particles may be fed from the container to the passage in the head, means for supplying blast particles to the container, and an impeller in the container for feeding such particles through the passage in the container, the impeller having radial blades.'
If this claim is infringed, it would follow, as a matter of course, that the other claims in suit are likewise infringed.
The accused structure is a blasting machine shown in drawings furnished by defendants in response to interrogatories (Plff. Exs. 9 and 10); and the plaintiff contends that so far as concerns directional control, the devices are structurally and functionally identical.
The defendants contend that the patent in suit is invalid, that they do not infringe, and that the defendants' machine was developed prior to the Peik patent.
The defense of non-infringement rests upon the fact that the accused structures are a 'slider' type of machine and are different structurally and in principle of operation from the 'batter' type of machine of the patent in suit.
The defense of origination of the accused structures prior to the date of the conception of Peik rests on the contention by defendants that everything in common to the patent in suit and the accused structure was designed, built and tested prior to the Peik conception and development.
On the issue of validity, we find for the plaintiff. The idea of centrifugal blasting with a rotating wheel did not originate with the patent in suit, but no practical machine was devised until Peik came to the field. The commercially practical art in abrasive cleaning was by air blasting and the old tumbling barrel. The plaintiff was the first to put on the market in this country a centrifugal blasting wheel. This wheel embodies the invention of Hollingsworth, which is now owned by plaintiff. This machine was displayed at the Foundrymen's Convention in Chicago, June 20-23, 1933. This wheel is not cited in defendants' answer as anticipatory of the patent in suit. It is operated with a shroud around its periphery to assist in directing the abrasive. These shrouds wore out rapidly and had to be replaced. The problem of directional control of the discharge blasts was solved by Peik. He did it by devising a wheel which would receive the abrasive at the center in such manner that the abrasive was fed over the inner ends of throwing blades and discharged from the periphery of the wheel throughout a limited arc in any desired zone about the wheel. The claims in suit are all directed to that phase of the invention and define a combination of wheel, container (Control cage), and impeller acting to discharge abrasive from the periphery of the wheel at any desired sector in a limited and controlled arc.
The claims of the patent in suit are not limited to the particular type of spiral throwing blades preferred by Peik, so that the form of the throwing blades is not involved in this suit.
The utility and commercial success of plaintiff's blast-cleaning device have amply been established. We have no hesitation in finding that the claims of patent in suit are valid.
Comparing now the accused structure with typical claim 16 of the Peik patent, we have no difficulty in reading it upon the defendant device.
Defendants assert that the accused structure does not respond to the requirement of the claim for a 'central opening.' We construe this to be the space defined by by the inner ends of the throwing vanes, which receives the container and impeller. We find precisely the same central space in defendants' structure. Defendants assert that the accused structure does not have the 'passages' of the claims of this patent, but only 'channels.' This we regard as a distinction without a difference. Whether you call the space between the blades 'passages or channels' does not make any difference in the operation of the wheel, because it is the space through which the abradant passes in both structures. Defendants assert their blades are not like those of the patent in suit. As we read the claims of the Peik patent in suit, they are not limited to the ...