Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
165 words
A heat sink fan comprising: a fan motor having blades; a first casing having a plurality of comers and one surface and holding said fan motor at said one surface; a second casing including a flat bottom portion having side edges, heat dissipating fins extending perpendicularly from said side edges, and corners defined between adjacent heat dissipating fins facing said one surface of said first casing; and mechanically interlocking means for mechanically locking together said first and second casing; wherein said first and second casings have centers; and said mechanically interlocking means comprises extending portions at said corners of said first casing each having a pawl, and a projection formed thereon, and facing said corners of said second casing, stepped portions formed on said corners of said second casing for interengagement with said pawls on relative rotation of said casings, and depressions formed in said corners of said second casing for receiving said projections and for securing the casings against relative rotation and pawl-step disengagement.
Claim 2
Dependent Claim
165 words
A heat sink fan comprising: a fan motor having blades; a first casing having a plurality of comers and one surface and holding said fan motor at said one surface; a second casing including a flat bottom portion having side edges, heat dissipating fins extending perpendicularly from said side edges, and corners defined between adjacent heat dissipating fins facing said one surface of said first casing; and mechanically interlocking means for mechanically locking together said first and second casing; wherein said first and second casings have centers; and said mechanically interlocking means comprises extending portions at said corners of said first casing each having a pawl, and a projection formed thereon, and facing said corners of said second casing, stepped portions formed on said corners of said second casing for interengagement with said pawls on relative rotation of said casings, and depressions formed in said corners of said second casing for receiving said projections and for securing the casings against relative rotation and pawl-step disengagement.
Claim 3
Dependent Claim
119 words
A heat sink fan according to claim 1, wherein each of said pawl comprises a fitting face substantially parallel to said one surface of said first casing and extending inward of said heat sink fan and an inclined face contiguous to said pawl, and said pawl receiving portion includes a pawl receiving flange comprising a pawl receiving face substantially parallel to said one surface of said first casing and extending outward of said heat sink fan and an inclined face contiguous to said pawl receiving face, and wherein an angle defined between said fitting face and said inclined face contiguous thereto is not larger than an angle defined between said pawl receiving face and said inclined face contiguous thereto.
Claim 4
Dependent Claim
34 words
A heat sink fan according to claim 2, wherein said fitting face of said pawl has a depth and said extending portion has a thickness; and said depth is not larger than said thickness.
Claim 5
Dependent Claim
57 words
A heat sink fan according to claim 1, wherein said pawls are provided on said corners of said first casing on at least one diagonal line of said first casing, and said pawl receiving flanges formed on said corners of said second casing corresponding to said corners of said first casing on which said pawls are formed.
Claim 6
Dependent Claim
47 words
A heat sink fan according to claim 1, wherein said mechanically interlocking means includes at least one guide groove extending in a circumferential direction with respect to said corners of said first and second casings and directed toward said depression for guiding said projection to said depression.
Claim 7
Dependent Claim
31 words
A heat sink fan according to claim 5, wherein each of said corners of said other casing has a raised land in which said depression and said guide groove are formed.
Claim 8
Dependent Claim
32 words
A heat sink fan according to claim 6, wherein said projection and said land each have heights, and said height of said projection is not less than said height of said land.