Gripping device
First Claim
1. A gripping device for an apparatus for placing components on a substrate, the device comprising a pair of grippers, each of which comprises a gripper jaw and at least one of which is movable relative to the other to close and open the jaws for gripping and releasing a component, characterised by a stroke-limiting device which is arranged for abutment with a first gripper of said pair of grippers after an initial relative movement between the grippers in the direction to open the jaws so as to limit said initial relative movement between the grippers in this direction, the stroke-limiting device comprising an abutment member which is capable of limited movement relative to said first gripper in the directions of relative movement between the grippers and which has an abutment surface for cooperation with an abutment surface on the first gripper to limit said relative movement of the abutment member in one direction, means being provided for urging the abutment member in the opposite direction to a position in which the abutment surfaces are spaced from one another, and means being provided for locking the abutment member to the second gripper of said pair of grippers against movement relative thereto at least in one direction such that initial relative movement between the grippers in the direction to open the jaws brings the abutment surfaces into engagement with one another to prevent further relative movement between the grippers in that direction, the locking means being releasable to free the abutment member so as to permit further relative movement between the grippers in said direction.
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Accused Products
Abstract
A gripping device for an apparatus for placing electronic and/or electrical components on a substrate comprises a pair of grippers (1 and 2) which are movable relative to one another to close and open the jaws (4 and 5) of the grippers. The device is intended for use in an apparatus which is designed to handle components of different widths, and the device is constructed so that the gripper jaws can be opened wide enough to accommodate the widest component. In order to reduce the space required between the components on the substrate for the opening of the jaws to release a component (6) after it has been placed on the substrate, a stroke-limiting device is provided which is arranged for abutment with one of the grippers after an initial relative movement between the grippers in the direction to open the jaws, so that the initial stroke of the grippers in this direction is limited to a small amount which is sufficient to release the component. The gripping device is then raised above the component and the stroke-limiting device is rendered inoperative so that the jaws can be fully opened. The stroke-limiting device comprises an abutment member (7) in the form of a rod (8) which is slidable in a bore (11) in one of the grippers (1) and has a head (9) with an abutment surface (12) for cooperation with an abutment surface (14) on that gripper, a spring (16) being arranged to urge the abutment member (7) to a position in which the abutment surfaces are spaced from one another (FIG. 1). The rod also extends between two clamping members (18 and 19) in the other gripper (2), which clamping members are operable by fluid pressure to clamp the rod between them to lock the abutment member to this gripper. In the locked operative condition of the abutment member the gripper jaws can be opened only by a small initial amount which is determined by the abutment of the two abutment surfaces. The abutment member is rendered inoperative by releasing the clamping members. The grippers can then be opened fully.
19 Citations
8 Claims
- 1. A gripping device for an apparatus for placing components on a substrate, the device comprising a pair of grippers, each of which comprises a gripper jaw and at least one of which is movable relative to the other to close and open the jaws for gripping and releasing a component, characterised by a stroke-limiting device which is arranged for abutment with a first gripper of said pair of grippers after an initial relative movement between the grippers in the direction to open the jaws so as to limit said initial relative movement between the grippers in this direction, the stroke-limiting device comprising an abutment member which is capable of limited movement relative to said first gripper in the directions of relative movement between the grippers and which has an abutment surface for cooperation with an abutment surface on the first gripper to limit said relative movement of the abutment member in one direction, means being provided for urging the abutment member in the opposite direction to a position in which the abutment surfaces are spaced from one another, and means being provided for locking the abutment member to the second gripper of said pair of grippers against movement relative thereto at least in one direction such that initial relative movement between the grippers in the direction to open the jaws brings the abutment surfaces into engagement with one another to prevent further relative movement between the grippers in that direction, the locking means being releasable to free the abutment member so as to permit further relative movement between the grippers in said direction.
Specification