This application is based on Patent Application No. 2001-151234 filed May 21, 2001 in Japan, the content of which is incorporated hereinto by reference.
1. Field of the Invention
The present invention relates to a socket for an electronic element such as integrated circuit package, semiconductor device and the like, and in particular to a socket having a contact opening function enables contacts of the socket to open for an insertion of the electronic element into the socket and a removal of the electronic element from the socket.
2. Description of the Related Art
Conventionally, an IC package used in various electronic apparatuses is inserted in an IC socket for the purpose of carrying out an electrical characteristics test and a burn-in and reliability test and of mounting the IC package to a printed circuit board or the like. Conventionally, the IC socket has a generally rectangular socket body and a plurality of contacts arranged in the socket body, each contact including a movable piece and a stationary piece.
Such IC sockets include a socket having a contact opening function for electrically connecting the contact with a package lead and releasing the electric connection of the contact of the socket from the package lead. For example, Japanese Patent No. 2973406 discloses a conventional IC socket with a contact opening function.
In the IC socket of the above-mentioned patent, a plurality of contacts are arranged in a grid pattern on a generally rectangular socket body. The IC socket includes an actuating member having one end rotatably supported by the socket body and the other end having a cam surface (a slanted surface), and a movable plate slidable on the socket body. The movable plate has a cam follower surface in contact with the cam surface of the actuating member. The movable plate has a plurality of contact displacing portions respectively positioned between the movable piece and the stationary piece of each contact. A rotary axis of the actuating member extends parallel to one edge of the socket body. The movable and stationary pieces of each contact are opposite to each other in the direction in which the one edge of the socket body extends substantially perpendicular to the rotary axis of the actuating member.
When the actuating member is rotatably pushed down, the cam surface of the actuating member cooperates with the cam follower surface of the movable plate to slide the movable plate in one direction on the socket body. As the movable plate slides, each of the contact displacing portions of the movable plate moves the movable piece of the contact in one direction against the elastic force of the movable piece. As a result, a distance between the movable and stationary pieces is expanded (the contact is opened) so that the package lead can be inserted into a gap between the movable and stationary pieces of each contact.
When the push-down of the actuating member is released, each of the movable pieces returns to its original position to slide the movable plate in the direction opposite to the one direction and hold the package lead of the IC package in cooperation with the stationary piece opposite thereto. As a result, each of the contacts of the socket is electrically connected to the package lead of the IC package. When one wishes to release the IC package from the socket, the actuating member is again rotatably pushed down.
In the conventional IC socket, the contacts can be easily opened only by rotatably pushing down the actuating member with respect to the socket body as described above. In the conventional IC socket, however, since the movable and stationary pieces of the contact are opposite to each other in the direction in which one edge of the socket body extending substantially perpendicular to the rotary axis of the actuating member, it is difficult to obtain a sufficient displacement of the movable piece if the arrangement density of the contacts in the socket body is high. Accordingly, there is a requirement for an IC socket which can provide easy opening of the contacts and high arrangement density of the contacts in the socket body.
A socket for detachably holding various electronic elements of the present invention comprises: a socket body; a plurality of contacts arranged in the socket body, the contacts respectively including a movable piece and a stationary piece; a contact moving member slidably supported on the socket body, the contact moving member having a plurality of contact displacing portions respectively located between the movable and stationary pieces of each contact, and the contact moving member being urged to prevent the contact displacing portions from moving the movable pieces; a lever movably supported by the socket body and including a pushing portion at one end thereof and a pressing member at the other end thereof, the pressing member including a curved fulcrum portion and an operating portion curved oppositely to the fulcrum portion to be in contact with the contact moving member; a first restricting portion included in the socket body to be in contact with the fulcrum portion of the pressing member; and a second restricting portion included in the contact moving member, the second restricting portion capable of being in contact with the fulcrum portion of the pressing member.
Another socket for detachably holding various electronic elements of the present invention comprises: a socket body; a plurality of contacts arranged in the socket body, the contacts respectively including a movable piece and a stationary piece; a contact moving member slidably supported on the socket body, the contact moving member having a plurality of contact displacing portions respectively located between the movable and stationary pieces of each contact; and a lever for moving the contact moving member, the lever movably supported by the socket body and including a pushing portion at one end thereof and a pressing member at the other end thereof, the pressing member having substantially an S-shaped cross-section.
According to the present invention, it is possible to easily open each of the contacts only by pushing down the lever. Also, according to the present invention, it is possible to easily increase the arrangement density of the contacts in the socket body.