COMMISSIONER'S DECISION
Obviousness - Resilient Tires For Conveyor Wheels
A resilient tire is mounted on the hub of the conveyor roller in a "friction fit"
or "unbonded relationship." The unbonded feature permits the use of a low
hysteresis (normal) rubber, which provides an unexpected beneficial result.
Amended claims found allowable. New evidence presented at the Hearing satisfied
the Board and the examiner that the subject matter is patentable.
Final Action: Modified.
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This decision deals with a request for review by the Commissioner of
Patents of the Examiner's Final Action dated October 6, 1975, on applica-
tion 161,846 (Class 193-11). The application was filed on January 23,
1973, in the name of Andrew T. Kornylak, and is entitled "Resilient
Rollers." The Patent Appeal Board conducted a Hearing on August 17, 1977,
at which Air. P. Kirby represented the applicant. Also in attendance was
Mr. Y. Takada.
The application relates to a flanged wheel for a roller conveyor. An
elastomeric tire, narrower than the wheel rim, is mounted in the rim in
a "friction fit" or "unbonded" relationship. The unbonded feature (that is
the tire is not fixed to the hub) allows the use of a low hysteresis
(normal) rubber.
In the Final Action the examiner refused the application for failing to
define patentable subject matter over the following United States patents:
2,854,052 Sept. 30, 1958 Smith
3,443,674 May 13, 1969 Kornylak
The Smith patent relates to a tire and rim assembly. The object is to
provide a tire and rim assembly, incorporating a resilient tire and a
rigid rim, which may be subject to extreme overloads without damaging
or affecting the normal operation of the tire at normal loads. Figure 1,
shown below, is illustrative of that invention:
(See formula 1)
The Kornylak patent relates to a rollerway for a roller conveyor adapted to
handle heavy loads, such as heavy loaded pallets. Figure 1, shown below,
illustrates that arrangement.
(See formula 2)
In the Final Action the examiner stated his position (in part) as follows:
...
This application stands rejected for failing to define any
invention over this art. Roller conveyors are well known
as shown by United States Patent 3,443,674, noted on page 2
line 3 of the instant application. To substitute a tire and
rim like that of Smith into such known roller conveyor
arrangement is held to be but expected skill. The same
results are achieved by Smith as applicant, by the same means and
for the same reasons. To provide axial corrugations is held to be
but expected skill.
As regards the "bonded" attachment in Smith it is noted that
column 2 line 12 refers to a "demountable type" as well which
is clearly not bonded. As regards applicant's comments re the
deformation just up to the elastic limit in the instant device,
it is noted that Smith, column 1 lines 21-37 states that his
tire is to be compressed "under load to an extent slightly less
than that at which rupture or breakdown of the tire would occur".
It is held that this point is the same as that in applicant's
although expressed in different terminology. Rupture or
breakdown it is held would occur when the elastic limit is
reached. Smith does show his tire at interface 14 occupying
the entire width of the channel, but as is evident from his
disclosure this is because he does not want to effect any
breaking of the bond at the interface under load, in his bonded
embodiment. In the unbonded embodiment this tire width at 14
would not be of any importance. Smith does show his tire of
narrower width than the channel over most of the height thereof.
...
The applicant in his response to the Final Action had this to say (in part)
as follows:
...
The Smith patent does disclose that the tire may be compressed
within the flanges due to the normal spacing, in the axial direction,
between the flanges and the tire, so as to protect the tire. As
set forth in column 3, lines 40-44, the tire and rail assembly is
intended to be used as the tail wheel of an airplane, but it may
be used advantageously for any purpose where extreme overloads
of short duration are likely to be encountered. Within the meaning
of a tail wheel for an airplane, there is certainly no extreme
overloads of this type to be encountered in a gravity roller
conveyor. At the time of the Smith patent, airplanes were generally
landing at speeds in excess of 100 miles per hour on hard surface
runways, for example, concrete. Unless special provisions are made
for rotating a landing wheel of an airplane prior to landing, for
example by turbine blades or an electic motor, the landing wheel
will be stationary with respect to the airplane when it strikes the
runway, and with it being realized that the runway has a speed
relative to the airplane of greater than 100 miles per hour, it is
seen that the forces tending to rotate the tire with respect to
the hub are tremendous, and it would be highly undesirable and
no doubt destroy the tire to have the tire rotate relative to the
hub under such conditions; the hub is generally provided with
roller bearings to provide for such acceleration from a stationary
position to speeds in access of 100 miles per hour. While the Smith
patent states that the tire 11, however, may be of a solid demount-
able type in which case a suitable means for mounting the tire must
be employed (column 2, lines 9-13), whatever mounting means would
be employed would certainly be designed to prevent any relative
rotation or movement between the inner bearing surface of the tire
and the outer bearing surface of the hub for the reasons mentioned
above, and the term demountable with respect to such a vehicle wheel
would have no more meaning than the fact that pneumatic tires of
automobiles are demountable from the rim, and these are not in any
sense provided so as to be relatively moveable in use. Therefore,
the Smith patent does not have any teaching with respect to the tire
being loosely mounted on the hub for relative movement in the axial
and circumferential direction with respect to the hub as present-
ly claimed, and any modification of the Smith patent in this
direction would render the Smith wheel inoperative for its intend-
ed use as an airplane landing tail wheel.
One of the main points at the Hearing centered around the lack of clarity in
an affidavit which was submitted on May 14/76 by the applicant and signed by
Mr, Charles P. Tabler. At the Hearing the Board extended the applicant an
opportunity to clarify certain issues including some points in that affidavit.
On November 9, 1977 the applicant submitted an expanded affidavit by Mr.
Tabler and also presented further arguments to clarify some of the issues
raised at the Hearing. He also stated that he was willing to cancel all the
claims except claims 9 to 11. These claims were submitted, with minor amend-
ments, in the above mentioned response of November 9, 1977. Claim 9 reads as
follows:
A gravity undriven roller conveyor, comprising: a stationary
inclined rigid conveyor support; a plurality of substantially
identical idler conveyor rollers serially arranged in a
conveying direction downw-ardly along said inclined conveyor
support; bearing means freely rotatably mounting each of said
conveyor rollers on said conveyor support with parallel axes
of rotation in a common inclined plane, said axes being
perpendicular to said conveying direction down said inclined
plane for supporting loads on said conveyor rollers and convey-
ing loads from the top of said inclined conveyor support to
the bottom of said inclined support. solely by gravity; each of
said rollers having a rigid wheel including an outer annular
bearing surface concentric with its axis of rotation and a pair
of axially spaced flanges integrally extending radially out-
wardly from axially opposed sides of said outer annular bearing
surface; an annular tire of elastomeric material mounted on each
wheel between said flanges and normally being of less axial
width throughout its thickness than the corresponding axial
space between said flanges; said tire having an inner annular
bearing surface of complimentary shape with said wheel outer
bearing surface for transmission of rotation thereto, said tire
being mounted unbonded on said wheel for axial and circumferential
relative movement between said inner and outer bearing surfaces
of said tire and wheel respectively when the material of the
tire is compressed; said tire having a radial thickness greater
than the radial depth of said flanges; said elastomeric material
of said tire having an elastic limit by which it acquires a
permanent deformation when radially compressed; and said
flanges being of a radial depth relative to the radial
thickness of said tire to completely receive the elastomer-
ic material of the tire and directly engage a load being
conveyed before the elastic limit of said elastomeric
material is reached under radial compression by the load being
conveyed.
In the prior art, high hysteresis rubber tires had been used to give good
speed control of articles on a conveyor. These tires had been bonded to
appropriate hubs. The use of normal (low hysteresis) rubber tires when bonded
to hubs had caused uncontrolled run-away of articles on conveyors. Thus it
was thought that the only way to solve the run-away problem was to use high
hysteresis rubber tires. The prior use of normal rubber tires when bonded did
not provide for speed control as the speed and acceleration increased sub-
stantially with an increase in load.
It is significant to note from the affidavits, that when a high hysteresis
rubber tire is bonded the speed control is good with some slight slowing of
the article as the load increases, but that merely unbonding this same tire
provides a remarkable slow-down as load is increased. It is clear that unbonding
the high hysteresis rubber tire in and of itself provides a substantial increase
in load restraint. It is also clear that unbonding a normal rubber tire restrains
the run-away condition that was associated with that arrangement when bonded,
and in fact provides a very satisfactory conveyor with excellent speed control.
The present application in setting forth the fine speed control obtained by
merely unbonding the tire (particularly when made of low hysteresis rubber)
from its hub provides an unexpected beneficial result. This we believe sufficient
to hold claims 9 to 11 allowable.
We find it unnecessary to comment further, because at the Hearing the
examiner was satisfied that claims 9 to 11 would be allowable if the points
made in the original affidavit were explained to his satisfaction. This was
done in the submission of November 9, 1977.
We are satisfied that claims 9 to 11 are in allowable form and recommend
the allowance of these claims when presented as claims 1 to 3.
J.F. Hughes
Assistant Chairman
Patent Appeal Board, Canada
I have reviewed the prosecution of this application and I agree with the
recommendation of the Patent Appeal Board. Accordingly, I will accept claims
9 to 11 when presented as claims 1 to 3 and so request that amendment. The
application is returned to the examiner for resumption of prosecution.
J.H.A. Gariepy
Commissioner of Patents
Dated at Hull, Quebec
this 29th. day of November, 1977
Agent for Applicant
Kirby, Shapiro, Curphey & Eades
77 Metcalfe St.
Ottawa, Ont.
K1P 5L6