Knock sensor for combustion engines

Claim 2

In a knock sensor for an internal combustion engine comprising: a housing mounted on a body of an internal combustion engine; a vibration portion which is accommodated in said housing and which has a vibration unit that resonates at a knocking frequency of the internal combustion engine; a converter element which converts a compression force into electric signals; and a force which is generated at said vibration unit to said converter element as a compression force, wherein said vibration unit consists of a thin flange portion formed around the periphery of said weight and a thick ring portion formed around said thin flange portion.

Claim 3

A knock sensor for an internal combustion engine according to claim 1, wherein the outer periphery of said ring-like thick portion remains in a free condition relative to the inner wall of said housing.

Claim 4

A knock sensor for an internal combustion engine according to claim 1, wherein the outer periphery of said ring-like thick portion is secured to the inner wall of said housing.

Claim 5

A knock sensor for an internal combustion engine according to claim 1, wherein said vibration portion is constructed by of the same metal member as said weight as a unitary structure, and said thin portion and said thick portion are formed nearly in flush with each other.

Claim 6

A knock sensor for an internal combustion engine comprising: a cylindrical housing which is mounted on the body of an internal combustion engine, and which vibrates together with the body of the internal combustion engine; a piezo-electric element which is placed on the bottom on the inner side of said housing; a weight placed on said piezo-electric element; a vibration portion which is constructed together with said weight as a unitary structure, and which is made of the same metal material as said weight that consists of a thin flange portion formed around the outer circumference thereof and a thick ring portion formed around the outer circumference of said thin flange portion nearly in parallel with the bottom surface of said housing; a screw for fastening said weight and said element onto the bottom surface on the inner side of said housing with a predetermined fastening force; and means for taking out the output of said piezo-electric element from said housing.

Claim 7

A knock sensor for an internal combustion engine comprising: a cylindrical housing which is mounted on the body of an internal combustion engine, and which vibrates together with the body of the internal combustion engine; a piezo-electric element which is placed on the bottom on the inner side of said housing; a weight placed on said piezo-electric element; a vibration portion which is constructed together with said weight as a unitary structure, and which is made of the same metal material as said weight that consists of a thin flange portion formed around the outer circumference thereof and a thick ring portion formed around the outer circumference of said thin flange portion nearly in parallel with the bottom surface of said housing; a screw for fastening said weight and said element onto the bottom surface on the inner side of said housing with a predetermined fastening force; and means for taking out the output of said piezo-electric element from said housing.

Claim 8

A knock sensor for an internal combustion engine comprising: a cylindrical housing which is mounted on the body of an internal combustion engine, which vibrates together with the body of the internal combustion engine, and which forms a stepped portion in the inner peripheral edge of the housing; a vibration portion which is fastened at its outer periphery to said stepped portion, and which consists of a rigid metal plate forming a thick portion at the center thereof; a piezo-electric element placed on said thick portion; a weight placed on said piezo-electric element; a screw for fastening said piezo-electric element and said weight to said thick portion with a predetermined fastening force; and means for taking out the output of said piezo-electric element from said housing.

Claim 9

A knock sensor for an internal combustion engine comprising: a cylindrical housing which is mounted on the body of an internal combustion engine, which vibrates together with the body of the internal combustion engine, and which forms a stepped portion in the inner peripheral edge of the housing; a vibration portion which is fastened at its outer periphery to said stepped portion, and which consists of a rigid metal plate forming a thick portion at the center thereof; a piezo-electric element placed on said thick portion; a weight placed on said piezo-electric element; a screw for fastening said piezo-electric element and said weight to said thick portion with a predetermined fastening force; and means for taking out the output of said piezo-electric element from said housing.

Claim 10

In a knock sensor for an internal combustion engine comprising: a housing mounted on a body of an internal combustion engine; a vibration portion which is accommodated in said housing and which has a vibration unit that resonates at a knocking frequency of the internal combustion engine; a converter element which converts a compression force into electric signals; and a weight that transmits a force which is generated at said vibration unit to said converter element as a compression force; wherein said vibration portion is secured to said housing, and further comprising means for holding said weight and said converter element together while exerting a predetermined load, said means for holding comprising a fastener for securing said weight and said converter to said vibration portion with the converter situated between the weight and the vibration portion.

Claim 11

In a knock sensor for an internal combustion engine comprising: a housing mounted on a body of an internal combustion engine; a vibration portion which is accommodated in said housing and which has a vibration unit that resonates at a knocking frequency of the internal combustion engine; a converter element which converts a compression force into electric signals; and a weight that transmits a force which is generated at said vibration unit to said converter element as a compression force; wherein said vibration portion is secured to said housing, and further comprising means for holding said weight and said converter element together while exerting a predetermined load, said means for holding comprising a fastener for securing said weight and said converter to said vibration portion with the converter situated between the weight and the vibration portion.

Claim 12

A knock sensor according to claim 7, wherein the vibration portion comprises a disk-shaped member that is secured to the housing at its periphery.

Claim 13

A knock sensor according to claim 7, wherein said fastener comprises a screw passing through said weight and said converter element.