Patents

Decision Information

Decision Content

   IN THE CANADIAN PATENT OFFICE

  DECISION OF THE COMMISSIONER OF PATENTS

 

Patent application 487,869 having been rejected under Rule 47(2)

of the Patent Regulations, the Applicant asked that the Final

Action of the Examiner be reviewed. The rejection has

consequently been considered by the Patent Appeal Board and by

the Commissioner of Patents. The findings of the Board and the

ruling of the Commissioner are as follows:

 

Agent for Applicant

 

Kirby, Eades, Gale, Baker & Potvin

Box 3432, Station D

Ottawa, Ontario

K1P 6N9

 

This decision deals with the Applicant's request for review by

the Commissioner of Patents of a Final Action on application

serial number 487,869 (Class 310-22), assigned to Matsushita

Electric Industrial Co. Ltd. The inventors of the application,

entitled "Small Electric Motors," are S. Uda, H. Takao and S.

Kondo. The examiner issued a Final Action on December 21, 1989,

refusing claims 1 to 16 for lack of inventive ingenuity. A

hearing was held on January 15, 1992 at which Mr. Edwin J. Gale,

patent agent, represented the Applicant.

 

The application is directed to electric motors, specifically

small electric motors of the type used in tape recorders, video

tape recorders and the like, wherein specific organic compounds

are used to reduce abnormal operation.

 

Claim 1 of the application, as refused by the Examiner in the

Final Action, reads as follows:

 

A small electric motor having brushes and a commutator

slidably engaged with the brushes, wherein the interior or

(sic) the motor is filled with an atmosphere containing the

vapour of at least one organic compound having a boiling or

sublimation point of 40 to 350.degree.C and being selected from the

group consisting of paraffins, mono- or poly-hydric

alcohols, ethers, cyclic ethers, esters, ketones, ether

alcohols, ester alcohols, aminoalcohols, carboxylic acids,

amides, primary, secondary and tertiary amines, imidazoles,

imidazolines and monocyclic oxyterpenes.

 

In the Final Action, the examiner rejected claims 1 to 16 on the

grounds of obviousness in view of the following United States

patent:

 

2,703,372   issued March 1, 1955    Savage

 

The above United States patent relates to means for minimizing

brush wear in dynamoelectric machines operating under low

humidity conditions. Claim 1 of the United States patent reads

as follows:

 

In an air-cooled electrical machine comprising a current

collector device and relatively slidable current collector

contact member in engagement with said device, the method of

minimizing wear at the area of engagement of said device and

member comprising the steps of shielding said area from the

cooling air and providing to said shielded area a gaseous

medium comprising a vapour.

 

In the Final Action the examiner stated, in part:

 

Savage discloses an electric generator having brushes and a

commutator. The atmosphere inside the generator contains

vapours of organic compounds to reduce brush wear and

improve slidability between the brushes and the commutator.

These organic compounds are "alcohols, ethers, esthers

(sic), ketones, alcohol-ethers, amides and amines (column 4,

lines 49-51) provided on a felt (column 9, line 57) or

porous metals (column 9, line 58)."

 

Claims 1 to 16 are rejected because the subject matter

thereof lacks inventive ingenuity in view of the patent to

Savage, as the difference thereover is held to be obvious to

one of ordinary skill in the art to which the alleged

invention pertains.

 

Some of the compounds listed in claims 1 and 16 are

disclosed by Savage and the remaining organic compounds in

the claims are considered obvious alternatives in view of

Savage.

 

In his last amendment, dated June 13, 1989, the applicant

has amended claims 1 and 16 by specifying that the organic

compound has a boiling point or sublimation point of 40 to

350.degree.C. This feature is considered obvious because most of

today's electric motors operate within these temperature

limits and it is clear that if the interior of the motor has

to be filled with the vapour of an organic compound, the

organic compound selected must have a boiling or sublimation

point such that the compound will be vaporized by heat

during operation of the motor.

 

The applicant also argues in his letter dated June 13, 1989

that "the motor disclosed in United States Patent No.

2,703,372 is intended to be used at altitudes of the order

of 35,000 feet and more. Therefore the air or gas to be

supplied between the brush and the commutator contains

oxygen in a low concentration (page 2, lines 5-9)."

 

Applicant's attention is directed to column 2 lines 10-14 of

United States Patent 2,703,372 where it is clearly disclosed

that "the invention is applicable to polar regions of the

earth, desert regions and test chambers" From this

statement, it is clear that this motor is not intended to be

used only at-altitudes of the order of 35,000 feet and more.

The arguments presented by the applicant to explain the

effect of a low-oxygen concentration at page 2, lines 25-28

of his last letter ("the organic material is incompletely

burnt in the '372 patent, as the concentration of oxygen in

the air is small since the motor is to be used at the high

altitudes") are in contradiction with the other arguments

presented by the applicant at page 2, lines 10-13 of the

same letter ("in the '372 patent, a large energy is supplied

to the motor, an organic compound having a large molecular

weight of 9,000 can be used and the black material formed is

completely burnt").

 

The applicant also argues that "in the present invention,

the generation of such black materials is prevented so as to

maintain the electric contact between the brush and the

commutator" (applicant's letter dated June 13, 1989 bottom

of page 2).

 

At page 2, lines 4-5, of the disclosure the formation of the

black material is defined with the following terms: "a

mixture of carbon and metal powder formed between the

brushes and the commutator segments" and at page 5, lines

18-20 "probably a mixture with powder abraded from the brush

and the commutator".

 

Savage discloses, at lines 18-21 of column 2, that this

invention is particularly applicable to minimize wear of

carbonaceous brushes employed as current collector contact

members in electrical machines. From this statement it is

clear that the invention disclosed by Savage will also

reduce the formation of powder abraded from the brushes.

 

In response to the Final Action, dated June 21, 1990, the

applicant states, in part, as follows:

 

In a prior response to an Examiner's Action, applicant

argued that Savage related only to electrical equipment

operated at high altitude. As the Examiner correctly

pointed out, the Savage disclosure makes it clear that other

operating environments were contemplated. In trying to

identify the difference of the present invention from

Savage, the essential point was unfortunately not expressed.

The true difference of the present invention from Savage is

that Savage addresses quite a different problem from that of

the present invention and there is no reason for a person

skilled in the art to believe that the solution to the

problem addressed by Savage would be useful as a solution to

the problem addressed by the present invention.

 

The problem addressed by Savage is that of rapid brush wear

in electrical equipment of large current capacity when

operated in conditions of very low humidity because of the

lack of the lubricating effect normally caused by water

vapour in the air (see Column 1, lines 56 to 65). The main

operating environment of low humidity which Savage

contemplated was one of high altitude, and this was the

reason this was mentioned in the prior response, but he

suggested others (Column 2, lines 6 to 14). In all cases,

however, the message to be derived from Savage on a normal

reading of this document is that if you want to operate

electrical equipment of large current capacity in an

atmosphere of low humidity, you must use water vapour or the

vapours of organic materials to provide the necessary

lubrication or otherwise brush life will be severely

reduced.

 

The present invention, in contrast, is not necessarily

concerned with the problem of what happens in unusual

operating conditions of this type and is instead concerned

with the formation of "black material" during the operation

of electrical machines of small current capacity (such a

(sic) motors used for tape recorders and the like) under

normal operating conditions. The production of "black

material" does not necessarily lead to premature brush wear

(although this is often observed), but instead leads to

abnormal operating performance which reduces the

effectiveness of the equipment even if the brushes are still

within acceptable wear tolerances.

 

The harmful effects of "black material" are believed to be

limited to the operation of electrical equipment of small

current capacity rather than the equipment of large current

capacity of the type disclosed in Savage. Equipment of

large current capacity is apparently capable of overcoming

any problems caused by "black material."

 

Following the Hearing, the applicant submitted, on February 16,

1992, clarification with respect to the use of a mixture

containing 50% styrene in example 21 of the disclosure, and on

February 18, 1992 amendments to the disclosure and claims of the

application.

 

The issue before the Board is whether or not the claimed

invention is patentable in view of the above referenced United

States patent. Upon reading the Savage reference, the Board

extracts the following main points:

 

i) the United States patent is concerned with minimizing brush

wear or wear between the current collector and the engaging

contact member that occurs in larger types of electrical

motors and generators, particularly those used in aircraft;

 

ii) the problem addressed by the patent is premature brush wear

in large electrical motors operating under low humidity

environments such as at high altitudes or in a desert; and

 

iii) the solution to the problem is to provide a supply of water

vapour or vapours of organic compounds to the brush-

commutator environment.

 

The invention disclosed in the instant patent application is

concerned with the following:

 

i) improving the operational characteristics of small electric

motors, particularly wow and flutter problems associated

with these motors when used in tape recorders or video tape

recorders; and

 

ii) preventing the formation of hard, abrasive material

occurring under normal operating conditions, which causes

the above wow and flutter problems.

 

The applicants's solution to the above problem is to supply

vapours of organic compounds to the brush-commutator environment.

 

In determining the question of obviousness, the Board turns to

the following quotation from Beecham Canada Ltd. v. Procter &

Gamble Co. (1982), 61 C.P.R. (2d) 1, wherein it is stated at page

27:

 

The question to be answered is whether ... an unimaginative

skilled technician, in the light of his general knowledge

and the literature and information available on the subject

available to him ..., would have been led directly and

without difficulty to the invention.

 

The test the Board must apply to the present case is whether a

technician skilled in the art of small electric motors and their

operation in tape recorders and video tape recorders would, if

confronted with wow and flutter problems in the recorders, and

given the Savage disclosure, be lead directly and without

difficulty to apply gaseous organic vapours to such small motors

in order to reduce the operational problems associated therewith.

 

We note that the inventions described in the instant patent

application and in the United States patent generally relate to

extending the operating life of electrical motors. The basic

problems sought to be resolved are, however, quite different.

The patent is concerned with brush wear in large motors or

generators, whereas the application under consideration is

concerned with wow and flutter difficulties found in small

motors.

 

Moreover, the invention in the patent is designed to overcome

problems arising from the operation of motors or generators at

high altitudes or desert-type of environments having a low

humidity, while the invention under consideration is not

particularly concerned with that problem since the motor is

intended to operate under normal atmospheric conditions.

Finally, the lack of lubrication due to low humidity is addressed

in the patent, whereas the invention in the application is

concerned with preventing the formation of a hard, abrasive,

black material in the contact area between the brush and the

commutator of a small motor.

 

We also note that both the patent and the application under

consideration use organic compounds, selected from groups which

overlap in the two disclosures, to supply the desired vapour to

the brush-commutator area. All of said compounds are old and

known in chemistry, and the fact that the same or similar

materials are used to solve two distinctly different problems in

the operation of electric motors does not by itself lead us to

the conclusion that the instant invention is obvious.

 

Turning to the amended claims submitted on February 18, 1992, we

note that the claims have been amended and that the applicant has

added statements concerning the use, and operating voltage and

current of the motor. Amended claim 1 reads as follows:

A small-size motor of a type comprising brushes and a

commutator slidably engaged with the brushes and operated at

a voltage of 1 to 30V and with a current not larger than 1A,

as used in tape recorders, video tape recorders and the

like, a vaporized organic compound being provided in the

motor interior, characterized in that the motor interior is

filled with an atmosphere containing a vapour of at least

one organic compound selected from the groups consisting of

mono- or polyhydric alcohols, ethers, cyclic ethers,

ketones, ether alcohols, ester alcohols, aminoalcohols,

carboxylic acids, amides, primary, secondary and tertiary

amines, imidazoles, imidazolines and monocyclic oxyterpenes,

the organic compound having a boiling or sublimation point

between about 40 and 350.degree.C.

 

The Board is of the view that the amended claims define the

invention over the prior art cited by the examiner in the Final

Action. The Board therefore recommends that the amended claims

submitted on February 18, 1992 be accepted as overcoming the

Examiners's Final Action on the basis of lack of inventive

ingenuity.

 

F.H. Adams              V. Duy                  A. Legris

Chairman                Member                  Member

Patent Appeal Board           Patent Appeal Board     Patent Appeal Board

 

I concur with the findings and recommendation of the Patent

Appeal Board. I remand the application to the Examiner for

prosecution consistent with the findings of the Board.

 

M. Leesti

Commissioner of Patents

 

Dated at Hull, Quebec

this 13th day of May 1993

 You are being directed to the most recent version of the statute which may not be the version considered at the time of the judgment.