Device for sensing side positioning of wafers
First Claim
1. An apparatus for sensing positions of a member relative to a base when the member is placed on the base comprising:
- an arm mounted to the base, the arm being movable in a direction toward and away from the base, the arm having a projection extending a distance beyond the arm in said direction of movement of the arm toward the base and being located on the arm so that the projection comes into contact with the member as the arm is moved toward the base to determine a first position of the member relative to the base and the projection is free from contact with the member as the arm is moved toward the base to determine a second position of the member relative to the base, wherein the member in its first position causes the arm to occupy a detectable displaced position relative to the base, the displaced position of the arm being substantially displaced from a nondisplaced position that the arm occupies when the member is in its second position, the displacement being directly related to the extending distance and location of the projection.
2 Assignments
0 Petitions
Accused Products
Abstract
An apparatus is provided which determines whether a member is placed correctly on a base. The apparatus comprises an arm mounted for movement toward and away from the base which normally holds the member in place on the base. The arm has a projection which extends a distance beyond the surface of the arm and toward the base. When the member is in a first or third position relative to the base, the projection makes contact with the member. When the member is in a second position relative to the base, the projection clears the member and is positioned in close proximity to the side of the base. The apparatus determines the position of the member by sensing with a photosensor a corresponding position of the arm displaced from the base. The displacement distance of the arm relative to the base is due to the distance that the projection extends beyond the surface of the arm.
26 Citations
13 Claims
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1. An apparatus for sensing positions of a member relative to a base when the member is placed on the base comprising:
an arm mounted to the base, the arm being movable in a direction toward and away from the base, the arm having a projection extending a distance beyond the arm in said direction of movement of the arm toward the base and being located on the arm so that the projection comes into contact with the member as the arm is moved toward the base to determine a first position of the member relative to the base and the projection is free from contact with the member as the arm is moved toward the base to determine a second position of the member relative to the base, wherein the member in its first position causes the arm to occupy a detectable displaced position relative to the base, the displaced position of the arm being substantially displaced from a nondisplaced position that the arm occupies when the member is in its second position, the displacement being directly related to the extending distance and location of the projection. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
Specification