Wafer basket transfer apparatus

Claim 2

A wafer basket transfer apparatus for transferring baskets of semi-conductor wafers from one processing tank to an adjacent tank, comprising a stationary frame plate, a slide plate slideably mounted for vertical sliding movement relative to the frame plate, a basket lifting arm having a basket lifting hook at one end, drive means including a shaft in driving engagement with the other end of the lifting arm to rotate the arm in a vertical plane, said shaft being mounted for rotation in the slide plate and for vertical movement with respect to the frame plate, a cam mounted for rotation with the shaft, and a cam follower mounted on the frame plate and cooperating with the cam to raise and lower the slide plate with respect to the frame plate as the lifting arm rotates, the lifting arm being so oriented with respect to the cam as to carry the lifting hook in a curved, vertically elongated overhead path with respect to the frame plate, whereby a wafer basket may be lifted from a processing tank generally vertically upwardly to a substantial height and may be lowered generally vertically into an adjacent tank with the wafer basket clearing the tank edges.

Claim 3

The transfer apparatus of claim 1 wherein the drive means comprises a motor carried by the slide plate and connected to said shaft.

Claim 4

The transfer apparatus of claim 1 wherein the cam follower comprises a roller rotatably mounted to the frame plate below and in alignment with the cam, the weight of the apparatus borne by the slide plate urging the cam downward into engagement with the roller during a transfer operation.

Claim 5

The transfer apparatus of claim 1 wherein the lifting arm is oriented to travel in a vertical plane spaced forwardly of the frame plate, and the slide plate is spaced rearwardly of the frame plate, the frame plate having a vertically extending slot permitting vertical movement of the motor drive shaft extending through the slot.

Claim 6

The transfer apparatus of claim 4 wherein the slide plate has vertical edges with roller tracks formed therein, and wherein the frame plate is provided with rear-mounted rollers rolling in the tracks of the slide plate.

Claim 7

The transfer apparatus of claim 5 wherein the cam and cam follower are mounted between the spaced frame and slide plates.

Claim 8

The basket transfer apparatus of claim 1 including a horizontal basket lifting rod extending parallel to the axis of rotation of the lifting arm and having a transverse disc at its end engageable by the lifting hook, the lifting hook having a pair of upwardly opening slots configured to respectively engage the disc and rod with the disc-receiving slot rigidly engaging the disc to maintain the rod in a horizontal position during a transfer operation.

Claim 9

A wafer basket transfer apparatus for transferring baskets of semi-conductoR wafers from one processing tank to an adjacent processing tank, comprising: a stationary frame plate having a vertical slot therein; a slide plate spaced rearwardly of the frame plate and slideably mounted for vertical sliding movement relative to the frame plate; a motor affixed to and carried rearwardly of the slide plate, the motor including a drive shaft extending forwardly through the slot in the frame plate; a basket lifting arm spaced forwardly of the frame plate and having a basket lifting hook swingably mounted at one arm end with the other arm end being affixed to the motor drive shaft extending through the frame plate slot; a cam mounted to the motor drive shaft between the frame and slide plates, the cam being non-symmetrical with respect to the axis of rotation of the drive shaft; a cam follower roller rotatably mounted to the frame plate and positioned below and in contact with the cam; the lifting arm being so oriented with respect to the cam as to carry the lifting hook in a curved, vertically elongated overhead path with respect to the frame plate as the lifting arm is driven by the motor drive shaft, whereby a wafer basket may be lifted from a processing tank generally vertically to a substantial height and may be lowered generally vertically into an adjacent tank without interference of edges of the tank with the wafer basket.

Claim 10

A wafer basket transfer apparatus for transferring baskets of semi-conductoR wafers from one processing tank to an adjacent processing tank, comprising: a stationary frame plate having a vertical slot therein; a slide plate spaced rearwardly of the frame plate and slideably mounted for vertical sliding movement relative to the frame plate; a motor affixed to and carried rearwardly of the slide plate, the motor including a drive shaft extending forwardly through the slot in the frame plate; a basket lifting arm spaced forwardly of the frame plate and having a basket lifting hook swingably mounted at one arm end with the other arm end being affixed to the motor drive shaft extending through the frame plate slot; a cam mounted to the motor drive shaft between the frame and slide plates, the cam being non-symmetrical with respect to the axis of rotation of the drive shaft; a cam follower roller rotatably mounted to the frame plate and positioned below and in contact with the cam; the lifting arm being so oriented with respect to the cam as to carry the lifting hook in a curved, vertically elongated overhead path with respect to the frame plate as the lifting arm is driven by the motor drive shaft, whereby a wafer basket may be lifted from a processing tank generally vertically to a substantial height and may be lowered generally vertically into an adjacent tank without interference of edges of the tank with the wafer basket.

Claim 11

The wafer basket transfer apparatus of claim 8 wherein the slide plate has vertical edges with recessed, roller-receiving tracks therein, and wherein the frame plate includes horizontally spaced, vertically aligned rollers spaced rearwardly of the frame plate and riding in the recessed tracks of the slide plate and permitting the slide plate to move only substantially vertically with respect to the frame plate.