Patent ID: 7223040

Claim:
A binder, comprising: first binding members; second binding members moveable relative to and respectively engageable with said first binding members to form closed loops in a closed state of said binder; a first connecting member connecting said first binding members to each other and a second connecting member connecting said second binding members to each other, said first and second connecting members being moveable relative to each other; and a spring biasing the binding members away from the closed state and into an open state of said binder in which open state said loops are opened; wherein said first binding members are disengaged from the second binding members when said first binding members are moved toward each other or when said second binding members are moved away from each other, thereby allowing said disengaged binding members to subsequently move into the open state under action of said spring; said first and second connecting members have respective inner and outer sides, the inner sides of the connecting members are adjacent to each other and positioned lower than the outer sides thereof when said first and second binding members are engaged; the inner sides of the connecting members are shifted to a position higher than the outer sides thereof by said spring so that the loops formed by the first and second binding members are opened when the engagement between said first and second binding members is released; said connecting members are slanted relative to each other and define a V shape when said first binding members are engaged with the respective second binding members in the closed state of said binder; and said spring comprises a wire member that is located below said first and second connecting members and has a generally M- or W- shaped configuration defined by a first end section extending transversely of said binder from the outer side of said first connecting member to the outer side of said second connecting member; a first middle section contiguous to the first end section and extending transversely of said binder from the outer side of said second connecting member toward said first connecting member; a second middle section contiguous to the first middle section and extending transversely of said binder in a direction opposite to the first middle section back to the outer side of second connecting member; and a second end section contiguous to the second middle section and extending transversely of said binder from the outer side of said second connecting member to the outer side of said first connecting member; wherein said first and second end sections define a first portion and said first and second middle sections define a second portion which is biased by an elasticity of said wire member to swing upwardly from said first portion to bring the binder to the open state when said first binding members are disengaged from the second binding members.