Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
191 words
In a fuel pump of the type comprising a pump casing having a pump chamber therein, an impeller disposed in the pump chamber, a rotatable main shaft one end of which is connected to the center of the impeller to rotate said impeller, and a means for driving the main shaft, the improvement comprising a coupler engaging mechanically with both the impeller and the main shaft to prevent rotation of said impeller relative to said main shaft; said impeller having a central hole defined at the center thereof for receiving the main shaft, said impeller also having at least one pin hole therein spaced from said central hole; a first engaging portion formed on an end surface of the main shaft adjacent the portion of said main shaft which engages said central hole; and a pin formed integrally with the coupler and engaging with said pin hole in said impeller, said coupler also having a second engaging portion which engages with said first engaging portion on said main shaft, the cross section of each of said first and second engaging portions being noncircular in a plane perpendicular to said main shaft.
Claim 2
Dependent Claim
191 words
In a fuel pump of the type comprising a pump casing having a pump chamber therein, an impeller disposed in the pump chamber, a rotatable main shaft one end of which is connected to the center of the impeller to rotate said impeller, and a means for driving the main shaft, the improvement comprising a coupler engaging mechanically with both the impeller and the main shaft to prevent rotation of said impeller relative to said main shaft; said impeller having a central hole defined at the center thereof for receiving the main shaft, said impeller also having at least one pin hole therein spaced from said central hole; a first engaging portion formed on an end surface of the main shaft adjacent the portion of said main shaft which engages said central hole; and a pin formed integrally with the coupler and engaging with said pin hole in said impeller, said coupler also having a second engaging portion which engages with said first engaging portion on said main shaft, the cross section of each of said first and second engaging portions being noncircular in a plane perpendicular to said main shaft.
Claim 3
Dependent Claim
36 words
A fuel pump as claimed in claim 1 wherein the coupler is constructed in a dish-shape, said second engaging portion being formed on the bottom wall thereof, and said pin being formed on the circumference thereof.
Claim 4
Dependent Claim
52 words
A fuel pump as claimed in claim 1 wherein said first engaging portion is a groove defined on the end surface of the main shaft, and said second engaging portion is a projection formed on the bottom wall of the coupler at a position corresponding to that of said first engaging portion.
Claim 5
Dependent Claim
48 words
A fuel pump as claimed in claim 1 wherein said first engaging portion is a projection formed on the end surface of the main shaft, and said second engaging portion is a groove defined on the coupler at a position corresponding to that of said first engaging portion.
Claim 6
Dependent Claim
32 words
A fuel pump as claimed in claim 1 wherein the respective centers of gravity in the main shaft, impeller, and coupler are positioned on the rotational central axis of said main shaft.
Claim 7
Dependent Claim
38 words
A fuel pump as claimed in claim 1 wherein a plurality of said pin holes are defined on the impeller around said central hole, said pin holes being located symmetrically with respect to the center of said impeller.
Claim 8
Dependent Claim
54 words
A fuel pump as claimed in claim 1 wherein a third engaging portion is formed on the circumference of said main shaft in the vicinity of said end surface of the main shaft, and a fourth engaging portion which engages with said third engaging portion is formed on the inner wall of said coupler.