Press-fit pin fitting in a miniaturized through hole formed in a circuit board

Claim 2

A press-fit pin having a press-fitting portion to be press fit into a through hoe, said press-fitting portion comprising: a first beam extending along a longitudinal axis of said press-fitting portion; said first beam having a first larger beam and a first smaller beam, each of which is elastically bent along a line parallel to the longitudinal axis of said press-fitting portion when said press-fitting portion is press fit into said through hole; a second beam extending along the longitudinal axis of said press-fitting portion, said second beam having a second larger beam and a second smaller beam, each of which is elastically bent along a line parallel to the longitudinal axis of said press-fitting portion when said press-fitting portion is press fit into said through hole; and a cross portion extending along the longitudinal axis of said press-fitting portion so as to connect said first beam and said second beam, said cross portion being elastically bent along a line parallel to the longitudinal axis of said press-fitting portion when said press-fitting portion is press fit into said through hole, said cross portion having a substantially uniform thickness; wherein said first beam is connected to said second beam with said cross portion therebetween so that said second beam is symmetric with said first beam with respect to a line including the longitudinal axis of said press-fitting portion, said first larger beam and said second larger beam extending upward from said cross portion so as to form an upper portion of a V, said first smaller beam and said second smaller beam extending downward from said cross portion.

Claim 3

The press-fit pin as claimed in claim 1, wherein said cross portion has a first spring constant K1, said first and second larger beams have a second spring-constant K2 and said first and second smaller beams have a third spring-constant K3, and wherein said first, second and third spring-constants have a relationship represented by K2<K1<K3.

Claim 4

The press-fit pin as claimed in claim 1, wherein each of said first and second beams is connected to said cross portion with a gentle curve so that a stress generated in an area adjacent to a root of each of said first and second beams is not concentrated.

Claim 5

The press-fit pin as claimed in claim 1, wherein each of said first and second larger beams and said first and second smaller beams has a rounded contacting portion to be contacted to an inner surface of said through hole, a radius of curvature of said round portion being determined so that a load exerted on said round portion is dispersed.

Claim 6

The press-fit pin as claimed in claim 4, wherein the radius of curvature of said rounded contacting portion is 0.1 mm.

Claim 7

A connecting construction of a circuit formed on a circuit board to another circuit, said connecting construction comprising: a first circuit board on which a first circuit is formed; at least one press-fit pin press fit in a through hole formed in said first circuit board, said press-fit pin having a contacting portion being connected to said first circuit, and a press-fitting portion; said press-fitting portion comprising: a first beam extending along a longitudinal axis of said press-fitting portion, said first beam having a first larger beam and a first smaller beam, each of which is elastically bent along a line parallel to the longitudinal axis when said press-fitting portion is press fit into said through hole, a second beam extending along the longitudinal axis of said press-fitting portion, said second beam having a second larger beam and a second smaller beam, each of which is elastically bent along a line parallel to the longitudinal axis when said press-fitting portion is press fit into said through hole, and a cross portion extending along the longitudinal axis of said press-fitting portion so as to connect said first beam and said second beam, said cross portion being elastically bent along a line parallel to the longitudinal axis when said press-fitting portion is press fit into said through hole, wherein said first beam is connected to said second beam with said cross portion therebetween so that said second beam is symmetric with said first beam with respect to a line including the longitudinal axis of said press-fitting portion, said first larger beam and said second larger beam extending upward from said cross portion so as to form an upper portion of a V, said first smaller beam and said second smaller beam extending downward from said cross portion; wherein each of said first and second beams has a first spring constant, and said cross portion has a second spring constant different from said first spring constant and a substantially uniform thickness; and a jack connector having a first surface and a second surface facing different direction from said first surface, at least one insertion hole corresponding to said press-fit pin being formed on said first surface into which insertion hole an end of said press-fit pin is inserted, said jack connector comprising at least one contact member of which one end is accommodated in said insertion hole and the other end protrudes form said second surface, said one end of said contact member contacting to said end of said press-fit pin when said press-fit pin is inserted into said insertion hole.

Claim 8

A connecting construction of a circuit formed on a circuit board to another circuit, said connecting construction comprising: a first circuit board on which a first circuit is formed; at least one press-fit pin press fit in a through hole formed in said first circuit board, said press-fit pin having a contacting portion being connected to said first circuit, and a press-fitting portion; said press-fitting portion comprising: a first beam extending along a longitudinal axis of said press-fitting portion, said first beam having a first larger beam and a first smaller beam, each of which is elastically bent along a line parallel to the longitudinal axis when said press-fitting portion is press fit into said through hole, a second beam extending along the longitudinal axis of said press-fitting portion, said second beam having a second larger beam and a second smaller beam, each of which is elastically bent along a line parallel to the longitudinal axis when said press-fitting portion is press fit into said through hole, and a cross portion extending along the longitudinal axis of said press-fitting portion so as to connect said first beam and said second beam, said cross portion being elastically bent along a line parallel to the longitudinal axis when said press-fitting portion is press fit into said through hole, wherein said first beam is connected to said second beam with said cross portion therebetween so that said second beam is symmetric with said first beam with respect to a line including the longitudinal axis of said press-fitting portion, said first larger beam and said second larger beam extending upward from said cross portion so as to form an upper portion of a V, said first smaller beam and said second smaller beam extending downward from said cross portion; wherein each of said first and second beams has a first spring constant, and said cross portion has a second spring constant different from said first spring constant and a substantially uniform thickness; and a jack connector having a first surface and a second surface facing different direction from said first surface, at least one insertion hole corresponding to said press-fit pin being formed on said first surface into which insertion hole an end of said press-fit pin is inserted, said jack connector comprising at least one contact member of which one end is accommodated in said insertion hole and the other end protrudes form said second surface, said one end of said contact member contacting to said end of said press-fit pin when said press-fit pin is inserted into said insertion hole.

Claim 9

The connecting construction as claimed in claim 6, further comprising an insulator which isolates and insulates said press-fit pin mounted on said first circuit board, said end of said press-fit pin protruding from said insulator so that said end of said press-fit pin is inserted into said insertion hole when said jack connector is fit on said press-fit pin.

Claim 10

The connecting construction as claimed in claim 6, further comprising a second circuit board connected to said second surface of said jack connector so that a second circuit formed on said second circuit board is connected to said first circuit formed on said first circuit board via said contact member and said press-fit pin.