Printed-wiring-board holding apparatus

An apparatus for holding a printed wiring board, comprising:

• a holding table which has a flat upper surface and a plurality of negative-pressure-supply holes each of which has an opening in the upper surface;
• at least one holding member which is detachably attached to the upper surface of the holding table such at that a lower end surface of the holding member is held in close contact with a portion of the upper surface that surrounds the opening of a covered one of the negative-pressure-supply holes, the holding member having a negative-pressure passage which is formed therethrough to connect between the lower end surface thereof and an upper end surface thereof, the holding member, attached to the holding table, supporting, at the upper end surface thereof, the printed wiring board, and applying a negative pressure supplied from the at least one negative-pressure-supply hole via the negative-pressure passage thereof, to the board and thereby holding the board;
• and
• a plurality of opening and closing valves which are associated with the plurality of negative-pressure-supply holes, respectively, each of the opening and closing valves closing a corresponding one of the negative-pressure-supply holes in a state in which the holding member is detached from the portion of the upper surface of the holding table that surrounds the opening of the corresponding one negative-pressure-supply hole, and opening the corresponding one hole, in a state in which the holding member is attached to the portion of the upper surface, so that the corresponding one hole is communicated with the negative-pressure passage of the holding member, the each opening and closing valve comprising:
• a valve hole which is provided at an end portion of the corresponding one negative-pressure-supply hole on a side of the opening thereof and which has a diameter greater than a diameter of the one negative-pressure-supply hole;
• a valve-seat member which is fixedly provided on the holding table such that the valve-seat member covers an opening of the valve hole and which has a through-hole formed therethrough and a valve seat formed around the through-hole;
• a valve member which is provided in the valve hole such that the valve member is movable to a closing position where the valve member is seated on the valve seat and to an opening position where the valve member is away from the valve seat;
• a spring member which applies a biasing force to the valve member in a direction toward the valve seat;
• and
• a valve-opening projection which projects from one of the holding member and the valve member, and which engages, in a state in which the holding member is held in close contact with the portion of the upper surface of the holding table that surrounds the opening of the corresponding one hole, the other of the holding member and the valve member to position the valve member at the opening position against the biasing force of the spring member, and allows the valve member to be positioned at the closing position by the biasing force of the spring member in a state in which the holding member is not held in close contact with the portion of the upper surface of the holding table.

An apparatus for holding a printed wiring board, comprising:

• a holding table which has a flat upper surface and a plurality of negative-pressure-supply holes each of which has an opening in the upper surface;
• at least one holding member which is detachably attached to the upper surface of the holding table such that a lower end surface of the holding member is held in close contact with a portion of the upper surface that surrounds the opening of at least one of the negative-pressure-supply holes, the holding member including a seat portion having the lower end surface and a first transverse cross section, a pin portion projected from the seat portion and having an upper end surface and a second transverse cross section smaller than the first transverse cross section of the seat portion, and a negative-pressure passage which is formed through the seat portion and the pin portion to connect between the lower end surface and the upper end surface, the holding member, attached to the holding table, supporting, at the upper end surface of the pin portion, a local portion of the printed wiring board, and applying a negative pressure supplied from the at least one negative-pressure-supply hole, via the negative-pressure passage thereof, to the local portion of the printed wiring board and thereby holding the printed wiring board;
• and
• a plurality of opening and closing valves which are associated with the plurality of negative-pressure-supply holes, respectively, each of the opening and closing valves closing a corresponding one of the negative-pressure-supply holes in a state in which the holding member is detached from the upper surface of the holding table, and opening the corresponding one negative-pressure-supply hole, in a state in which the holding member is attached to the portion of the upper surface that surrounds the opening of the corresponding one negative-pressure-supply hole, so that the corresponding one negative-pressure-supply hole is communicated with the negative-pressure passage of the holding member.

An apparatus for conveying a printed wiring board, comprising:

• a board conveyor which includes two belts which cooperate with each other to convey the printed wiring board;
• and
• a board holding device which is provided between the two belts and which holds the printed wiring board conveyed by the two belts, the board holding device comprising:
• a holding table which has a flat upper surface and a plurality of negative-pressure-supply holes each of which has an opening in the upper surface;
• at least one holding member which is detachably attached to the upper surface of the holding table such that lower end surface of the holding member is held in close contact with a portion of the upper surface that surrounds the opening of at least one of the negative-pressure-supply holes, the holding member having a negative-pressure passage which is formed therethrough to connect between the lower end surface thereof and an upper end surface thereof, the holding member, attached to the holding table, supporting, at the upper end surface thereof, the printed wiring board, and applying a negative pressure supplied from the at least one negative-pressure-supply hole via the negative-pressure passage thereof, to the board and thereby holding the board;
• and
• a plurality of opening and closing valves which are associated with the plurality of negative-pressure-supply holes, respectively, each of the opening and closing valves closing a corresponding one of the negative-pressure-supply holes in a state in which the holding member is detached from the portion of the upper surface of the holding table that surrounds the opening of the corresponding one negative-pressure-supply hole, and opening the corresponding one negative-pressure-supply hole, in a state in which the holding member is attached to the portion of the upper surface, so that the corresponding one negative-pressure-supply hole is communicated with the negative-pressure passage of the holding member.

An apparatus for mounting electric components on a printed wiring board, comprising:

• a board conveyor which includes two belts which cooperate with each other to convey the printed wiring board;
• a board holding device which is provided between the two belts and which holds the printed wiring board conveyed b the two belts;
• and
• a component mounted device which mounts electric components on the printed wiring board held by the board holding device, the board holding device comprising:
• a holding table which has a flat upper surface and a plurality of negative-pressure-supply holes each of which has an opening in the upper surface;
• at least one holding member which is detachably attached to the upper surface of the holding table such that a lower end surface of the holding member is held in close contact with a portion of the upper surface that surrounds the opening of at least one of the negative-pressure-supply holes, the holding member having a negative-pressure passage which is formed therethrough to connect between the lower end surface thereof and an upper end surface thereof, the holding member, attached to the holding table, supporting, at the upper end surface thereof, the printed wiring board, and applying a negative pressure supplied from the at least one negative-pressure-supply hole, via the negative-pressure passage thereof, to the board and thereby holding the board;
• and
• a plurality of opening and closing valves which are associated with the plurality of negative-pressure-supply holes, respectively, each of the opening and closing valves closing a corresponding one of the negative-pressure-supply holes in a state in which the holding member is detached from the portion of the upper surface of the holding table that surrounds the opening of the corresponding one negative-pressure-supply hole, and opening of the corresponding one negative-pressure-supply hole, in a state in which the holding member is attached to the portion of the upper surface, so that the corresponding one negative-pressure-supply hole is communicated with the negative-pressure passage of the holding member.