Patents

Decision Information

Decision Content

IN THE MATTER OF a request for a review by the

Commissioner of Patents of the Examiner's Final

Action under Section 46 of the Patent Rules

(Prior to the Amendment by Order-in-Council

P.C. 1970-728 effective June l, 1970).

AND

IN THE MATTER OF a patent application serial

number 965,861 filed July 20, 1966 for an

invention entitled:

DISC BRAKES

Patent Agent for Applicant:

Messrs. Fetherstonhaugh & Co.,

Toronto, Ontario.

 

   This decision deals with a request for a review by the

Commissioner of Patents of the Examiner's Final Action rejecting

all the claims of application 965,861.

 

   The Patent Appeal Board has reviewed the prosecution of

this application and the facts are as follows:

 

   Application 965,861 filed July 20, 1966 in the name of

Harold Hodkinson relates to Disc Brakes and particularly to

rotatable brake discs for disc brake assemblies.

 

   In the prosecution terminated by the Final Action, the

Examiner refused to allow the application on the ground that

It fails to define patentable subject matter over the follow-

ing references:

United States Patent 2,380,085 - TACK et al

United States Patent 2,242,855 - FLOWERS

 

   During the prosecution of the application the Examiner

maintained that only expected skill and not inventive ingenuity

was involved in combining two of the several passage openings

disclosed by Tack et a1, to form a brake disc which differs

from the applicant's brake disc only by its lack of reinforc-

ing ribs and inclination of the passages.

      The examiner also pointed out that the use of reinforcing

   ribs in an air cooled brake disc is old in the art as shown

   by the patent to Flowers while inclining the passages is

   simply a matter of design choice requiring no inventive

   ingenuity.

 

      In applicant's letter of January 7, 1970, wherein the

   review by the Commissioner was requested, he argued:

 

  "In the construction disclosed in Figures 1-3 of the

   Tack specification openings 16 corresponding to the

   second openings 8 of the present invention are formed

   in alignment with the openings 16 corresponding to

   the first openings 7 of the present invention, and

   do not extend into the axially - extending racially

   inner surface of the central dished body portion.     

   Instead separate openings are provided on the inner

   surface of the central dished body portion".

 

Applicant maintains that this causes the plate 8 of the

   patent to Tack et al to have reduced conduction cooling compared

   with the corresponding part of applicant's disc.

 

   Applicant held:

 

   "Conduction of heat from the plate 8 of Tack's brake

   disc has to be through a narrow circuitous path

   because the plate 8 is connected to the central body

   portion only along the edges of each aperture 18 and

   consequently heat cannot be conducted in an axial

   direction through the central body portion along a linear

   path, as it can in a brake disc in accordance with the

   present invention, but initially has to follow a generally

   circumferential path through the webs of metal between

   the apertures 18 and the edge of the central body

   portion.

 

   "Thus the plate 8 of Tack's brake disc is subject to

   less efficient conduction - cooling than the corres-

   ponding part of a brake disc in accordance with the

   present invention and, therefore, stresses arising

   from the differential cooling rates of the two sides

   of the brake disc, which may lead to cracking of

   the disc, are more likely to arise in the disc

   disclosed in the citation.

 

   "Further, since the plate 8 of Tack's brake disc is

   connected to the central body portion along the

   edges of the apertures 18, the assembly is mechani-

   cally weaker than a brake disc in accordance with the

   present invention".

 Applicant continues and points out:

 

 "With regard to Tack's Figure 4 embodiment, it will

 be noted that there is no opening formed in the

 axially-extending radially inner surface of the

 central body portion. Consequently although this

 embodiment of the citation provides the plate 108

 with mechanical support and a heat conduction path

 comparable to that provided in the present invention,

 there is no flow of air from the central body

 portion through the ventilation passages is a

 generally radial direction. All the air flowing

 through the passage is forced to change direction

 through approximately 90 degrees and this provides

 resistance to the flow of air, reduces the rate of

 flow and, therefore reduces the rate of loss of heat

 from the disc".

 

      In his final argument applicant states that three steps

 are necessary to arrive at his disc.

 

 "It is necessary first to combine the disc construction

 shown in Figures 2 and 4 of the Tack specification, then

 add the reinforcing ribs disclosed in Flowers and made

 the further step of inclining the ribs.

 

 "Applicant submits that it is impossible to justify the

 Examiner's opinion that the three separate steps out-

 lined above are merely a matter of design or choice, as

 a considerable period of time has elapsed since the

 publication of the cited references and no one has

 previously produced a brake disc in accordance with

 the present invention".

 

      Upon review of the grounds set forth by the examiner,

 as well as all the arguments presented by the applicant I

 am not satisfied the rejection is well founded.

 

 Claim 1 of the application reads as follows:

 

A brake disc comprising a rigid assembly of an annular

 outer disc portion and a central dished body portion,

 the disc portion having formed therein a series of

 ventilation passages extending from a series of

 openings formed at the radially outer periphery of the

 disc portion to a series of openings formed at the

 radially inner periphery of disc portion, each of the ven-

 tilation passages extending in a direction which is

 inclined with respect to the direction of the adjacent

 radius of the disc portion including a series of first

 openings formed at circumferentially-spaced positions

 in the side of the disc portion axially nearer the base

of the central dished body portion, and a series of

second openings formed at circumferentially-spaced

positions in the side of the disc portion axially remote

from the base of the central dished body portion, the

second openings alternating with the first openings

around the radially inner periphery of the disc portion

and extending into the body portion to provide direct

communication in a generally radial direction with

respect to the brake disc between the central dished

body portion and the ventilation passages, each passage

having at its radially inner end only a first opening

or only a second opening.

 

   The basic reference United States Patent 2,380,085

issued July 10, 1945 to Tack discloses:

 

In a brake rotor, a substantially cylindrical support

member, a brake ring formed on the outer periphery

thereof and comprising a plurality of spaced plates,

fluid inlets formed in the side of said ring adjacent its

juncture with said member, said inlets communicating

with the space between said plates, the inlets in one

side of said ring being alternately arranged with respect

to the inlets on the opposite side of said ring.

 

   I should like to point out at this time that the question

is not whether the elements are new but whether the combination

of elements, with its arrangements of parts, is novel and the

result of inventive ingenuity. Furthermore it is necessary

only that there should be ingenuity exercised either in the

conception of the idea or in the method of applying it.

 

   The examiner appears to be dissecting the claims in order

to show lack of invention. The dissection of a combination

into its constituent elements and the examination of each

element in order to see whether its use was obvious or not is,

in my view, a method which ought to be applied with great

caution since it tends to obscure the fact that the invention

claimed is the combination.

 

   The applicant submits that his disc makes a considerable

advance in the art by solving the problem of cracking under

heavy braking and supports this assertion by affidavit. The

examiner agrees with this ".... applicant has indeed solved

the problem of cracking under heavy braking ...".

 

   The examiner also has stated that the reasons for

the cracking may not have been obvious. Here I find the

applicant has solved a problem wherein the solution was at

least unobvious. Furthermore, applicant states that discs

of the Tack type have been tested under racing conditions and

were found to be unsuitable in that the disc would crack at

high speeds.

 

   The examiner in his Final Action is basically using the

patent to Tack as a main reference and only uses the

patent to Flowers against claim 4. The examiner did not

specifically use the term anticipation, however the follow-

ing Court decision is of interest:  Balwin v. Western Electric

(1934)S.C.R. 94 at 103 "It is well established that for a

prior patent to constitute anticipation, the patent must

disclose the same or give information equal in practical

utility to that given by the patent in question." I am

satisfied that the patent to Tack does not give information

equal in practical utility to that given by this application.

 

   I find that the applicant has produced a new combination

of a disc brake with improvements of: (a) a different

arrangement of parts. (b) inclined ventilation passages.

 

   I am satisfied that the applicant has made a prima facie

showing of ingenuity. The Court has held, the commissioner

of Patents v. Hoechst (1964) S.C.R. 49: 25 Fox P.C. 99:

"The Commissioner should not refuse to allow an

application to proceed to the grant of a patent

unless he is quite satisfied that the subject

matter of the application could not conceivably be

patentable within the meaning of the Act.

 

   I recommend that the rejections against the allowance

of this application should be withdrawn.

R.E. Thomas,

Chairman,

Patent Appeal Board.

I concur with the findings of the Patent Appeal Board

and I am therefore setting aside the Final Action and returning

the application to the examiner for resumption of prosecution.

Decision accordingly

A.M. Laidlaw

Commissioner of Patents.

Dated at Ottawa, Ontario,

this 30th day of Novembers 1970.

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