COMMISSIONER'S DECISION
Obviousness - Apparatus for Separating Magnetic and Non-Magnetic Materials
The material is carried on a first conveyor towards a magnetic separator
which draws the magnetic material and deposits it on a second conveyor.
An air blast is also used to clean the magnetic material. The rejection
of some of the claims is affirmed, because the cited prior art teaches
essentially the same thing.
Final Action: Affirmed.
*****************
This decision deals with a request for review by the Commissioner of
Patents of the Examiner's Final Action dated March 15, 1976, on applica-
tion 178,489 (Class 209-57). The application was filed on August 9,
1973, in the name of Milbourn L. Smith et al, and is entitled "Counter
Air Flow And Magnetic Separation In A Shredded Refuse Classifier." On
September 10, 1977, the applicant cancelled a previous request for a
Hearing.
The application relates to apparatus for separating magnetic and non-
magnetic materials. The material is carried on a first conveyor towards
a magnetic separator which draws the magnetic material and deposits it on a
second conveyor, while at the same time allowing the non-magnetic material
to drop by gravity between the two conveyors. An air blast is also used
to remove minor amounts of non-magnetic material from the second conveyor.
This material is deposited between the conveyors with the other non-magnetic
materials. Figure 1, shown below, clearly depicts that arrangement:
(See formula 1)
In the Final Action the examiner refused claims 1 to 5, 12, 13 and 26 to 31
for "obviousness in view of the prior art," which is as follows:
Canadian Patents:
656,031 Jan. 15, 1963 Colburn
651,237 Oct. 30, 1962 Soper
Colburn discloses the use of a magnetic separating means bridging a separation
gap between two conveyors with at least an exit and entrance arranged in
"in-line" relationship. An air blast is also used to remove minor amounts
of non-magnetic material. Figure 6, shown below, is illustrative of that
invention:
<IMG>
The Soper patent discloses a means of purifying materials on an endless con-
veyor by magnetic separating means. This patent was cited to show that separa-
tion of material by magnetic means is common knowledge. Figure 5, shown
below, illustrates that invention:
<IMG>
In the Final Action the examiner ably presented his position (in part)
as follows:
...
Claims 1 to 5, 12 and 13 differ from the main reference in
that the second conveyor (not necessarily an endless belt) has
a conveyor path "inline" with the first conveyor path and in
that a means (not necessarily an air blast) for removing non
magnetic material (not necessarily pieces of scrap paper) from
itself is specified.
These differences, however, are obvious to implement by those
skilled in the art. Foreseeably a user of the Colburn device
may not have the space available to use a downwardly discharging
conveyor. The mere substitution of an endless conveyor (such
as conveyor 21 of Soper et al's device) to solve such a space
problem is obvious to those skilled in the art. Of course the
principle of cleaning by blowing away unwanted debris if not
universally obvious, is shown to be known to those skilled in
the art by its use in at least two places in the system disclosed
by the main reference (air blast means 80 and 95). Although
the applicant has taken two steps beyond the Colburn device, these
steps are so obvious that one would expect any skilled artisan
using this device to take exactly the same steps when faced with
space or other problems such as clean product distribution to
remote areas.
...
Claims 1 to 5, 12, 13 and 26 to 31 are refused, then, on the
grounds that the differences defined thereby over the main refer-
ence are obvious to make by those skilled in the art. The
tools, systems or principles representative of these differences
are shown to exist in both the main and common knowledge references.
The first difference is represented by the existence and varied
use of endless conveyors and the second by the showing in Colburn
of clean-up type air jets.
In response to the Final Action the applicant amended claim 1 and had this
to say (in part):
The Examiner relies on figure 6 of this patent [Colburn]. Figure 6
teaches a pair of conveyors 56b and 75, and a coil 67b is included
in the conveyor 75. The coil is connected to a source of alternat-
ing current 68b.
The conveyor 75 includes a plurality of elements 78 which are mag-
netizable and which collect magnetic particles from the mass of
particles 59b carried by the upperrun of the conveyor 56b.
Upon establishment of a demagnetizing field produced by the
coil 67b, the particles drop into the hopper 70b under the
assist of air directed from a nozzle 80.
It is noted that the upper run of the conveyor 56b is en-
circled by a cylinder 61b which is connected to a source of
energy 63b creating a magnetic field within the area of the
coil 62b as described at page 14 lines 23 et seq. of the
Canadian patent. Thus, in the Colburn patent, both of the
conveyors 56b and 75 include magnetic means which is not the
case in the teaching of the present application or in claim 1
which recites specifically that the second conveyor means
excludes magnetic means.
In paragraph 1 of page 2 of the Official Action, Examiner
states that the funnel 70b is a conveyor. Although applicant
does not dispute the fact that 70b can be considered to be
such a conveyor, it is noted that the path of the conveyor 56b
and the path of the funnel 70b are not in-line as per claim 1
hereof. Further, the two conveyors do not move material in
generally the same direction. As can be clearly seen in figure 6,
the motion of the material passing through the funnel 70b is at
right angles to the motion of the material moved by the conveyor
56b.
The purpose of the nozzle 80 in figure 6 of the patent is quite
distinct from the purpose of the means for removing as taught
in the present application and defined in claim 1. Thus, the
air blown by the nozzle 80 will remove particles from the con-
veyor 75. The means for removing defined in claim 1 removes
the minor amounts of nonmagnetic materials from the second conveyor
means.
The issue before the Board is whether or not claims 1 to 5, 12, 13 and 26 to
31 are directed to a patentable advance in the art. Amended claim 1 reads
as follows:
Apparatus for separating magnetically attractive and magnetically
non attractive materials comprising first movable means for con-
veying said materials along a first path, second movable means
for conveying excluding magnetic means contiguous said first convey-
ing means for conveying said materials along a second predetermined
path generally in line with said first path, said first and second
conveying means move said materials along said respective first
and second paths in the generally same direction, magnetic
means between said first and second conveying means for removing
said magnetically attractive material along with minor amounts
of said magnetically non attractive material from said first
conveying means and depositing the same upon said second conveying
means, and second means for removing said minor amounts from said
second conveying means.
We have considered with care the prosecution of this application and the
points and arguments made by the applicant. We find however, that the
response to the Final Action is replete with arguments concerning differ-
ences over the prior art. We are mindful however, that there must not
only be novelty in the combination, but also there must be ingenuity in
the invention (vide, Micro Nordstrom v Comer (1942) Ex. C.R. at p. 135).
It is therefore necessary to review the prior art (cited) and consider
its cumulative effect (vide De Frees and Betts Machine Co. v D.A. Acc. Ltd.
25 Fox Pat. C. 58 at 59) and then attempt to determine whether an
invention in the rejected claims is present.
After studying the patent to Colburn we find that the basic concept of
separating magnetic and non-magnetic materials by conveying the bulk materials
on a conveyor towards a magnetic separator, which in turn draws the magnetic
material from the bulk material is known in the art. The concept of using
air blasts for cleaning etc, is also known (see, for example, air blast
means 80 of Figure 6 supra). We find that all of the essential elements are
known. Any patentable advance in the art, therefore, must be found in
a novel combination which required a degree of inventive ingenuity for fruition.
We must therefore, scrutinize the combination claims with a care proportional
to the difficulty and improbability of finding invention in an assembly of
old elements. The real ultimate question is whether the combination is
obvious or not.
The applicant maintains that "... an analysis of the type performed by
the Examiner would lead to the conclusion that there is no such thing as
a system which is patentably unique." The facts however, do not coincide
with this statement, because the examiner has indicated that claims 6 to 11
and 14 to 25 are in allowable form.
The applicant points out that "the conveyors of the Soper patent are not
in line, for do they move material in the same direction." Soper does of
course show the use of endless belt type conveyors in magnetic separations.
We therefore think it is immaterial whether the conveyors are in line or
not, because the conceptual association is manifest by Soper. Any work-
able arrangement is normally within the skill of the trained worker in
this field.
The applicant argues that in his system "the stream of air performs a separ-
ating function. In contradistinction, the air from the nozzle 80 serves a
detaching function." This, in our view, is purely a case of semantics. In
the cited art the "air blast" removes particles from the surface of the
conveyor, while in the instant application it removes particles from the
magnetic material on the conveyor. Surely, if there was a problem of dirt
particles which should be removed, the answer is clearly inherent in the
teachings of the Colburn patent (see air blast means 80 - Figure 6 - supra).
The applicant stated that he was not clear on why the examiner cited the Soper
patent. Soper was cited to show what is common knowledge in the art. It
discloses a means of purifying materials on endless belt conveyors by magnet-
is separation means.
The applicant discussed one particular space problem in Colburn, e.g. the
length of the room. He correctly surmises that a chute would be preferable.
Consider a height problem in the Colburn arrangement assuming that there
is no room for the lower part of 70b. This problem could be solved by those
skilled in the art by several ways. They could slant 70b, they could replace
it by a channel shaped chute or as Soper has done (Figure 5), they could
use an endless conveyor. These clearly are choices readily available to
those skilled in the art without resorting to the use of the inventive faculty.
We turn now to a consideration of the claims. Claim 1 is essentially direct-
ed to two aligned, coplanar, endless conveyors mounted for co-directional
rotation but separated by a gap. This gap is spanned by a magnetic conveyor
operating above the plane of the gap to remove magnetic material from the
first conveyor and deposit it upon the second conveyor. Air current means
is used to separate non-magnetics (such as trapped particles) from the mag-
netics on the second conveyor. The non magnetic material from the first
conveyor is discharged into the gap. Some other features are stressed such
as the fact that the material is moving in the sane general direction, or in
other words the conveyor is "generally in line." As discussed above the prior
art shows endless belt conveyors, a system of three conveyors operating in
series with at least one separation gap and "air blast means" impinged on a
conveyor for cleaning purposes. One of the essential differences is that in
Colburn one of the conveyors is in the manner of a downwardly discharging
conveyor or funnel. To substitute an endless conveyor for the discharging
funnel is merely a matter of choice. Soper shows an endless conveyor conveying
the magnetic particles to a storage space. Another difference is in the
different arrangement of a well known principle of cleaning with the use of
an "air blast means."
In view of the above discussion and considerations we are not satisfied that
claim 1 is directed to a patentable advance in the art. In our view no result
has been achieved which can be considered to have flowed from an inventive
step. Patents cannot be sustained when their efforts are to substract from
former resources freely available to skilled artisans. In other words it would,
in our view, be an encroachment of the rights of artisans in this field to
grant a monopoly on the teachings of claim 1. We recommend that claim 1 be
refused.
Claims 2 to 5 and claims 12 and 13, which depend directly or indirectly on
claim 1, refer to alternatives in design or structure. The arguments used in
refusing claim 1 apply equally to them. They should also be refused.
Claims 26 to 31, which depend directly or indirectly on claim 1, specify
various designs in the magnetic means of separation. These do not add
features to claim 1 which would make them patentable combination. These
claims should also be refused.
In summary, we are satisfied that claims 1 to 5, 12, 13 and 26 to 31 are not
directed to a patentable advance in the art. We recommend that the decision
in the Final Action to refuse these claims be affirmed.
J.F. Hughes
Assistant Director
Patent Appeal Board, Canada
I have studied the prosecution of this application and I concur with the
recommendations of the Patent Appeal Board. Accordingly, I refuse to grant
a patent on claims 1 to 5, 12, 13 and 26 to 31. I will however, accept
claims 6 to 11 and 14 to 25. The applicant has six months within which to
cancel the refused claims and submit the appropriate amendment, or to appeal
my decision under the provision of Section 44 of the Patent Act.
J.H.A. Gari‚py
Commissioner of Patents
Dated at Hull, Quebec
this 20th. day of October, 1977