Magazine type slide projector with automatic focusing means

Claim 2

A slide projector comprising means for holding a picture slide in projection position, a projection lens movable in the direction of its optical axis for projecting an image of said slide onto a viewing screen, a carriage movable in the direction of said optical axis, automatic focusing light beam projecting means and receiving means both mounted on said carriage to move therewith, motor means controlled at least in part by said automatic focusing light beam projecting and receiving means for moving said projection lens axially, and disconnectable coupling means for coupling said carriage to said projection lens so that when said coupling means is effective, axial movement of said projection lens will cause corresponding axial movement of said carriage and said automatic focusing light beam means, and when said coupling means is ineffective, said projection lens may be moved axially by said motor means without tending to cause movement of said carriage or said automatic focusing light beam means.

Claim 3

A projector as defined in claim 1, further comprising spring means tending to keep said coupling means connected, and disconnecting means acting against the force of said spring means for rendering said coupling means disconnected.

Claim 4

A projector as defined in claim 2, wherein said disconnecting means includes a manually operable member.

Claim 5

A projector as defined in claim 3, wherein said manually operable member is a plunger reponsive to finger pressure.

Claim 6

A projector as defined in claim 3, wherein said disconnecting means includes an electromagnet and wherein said manually operable member is a manually operable switch Effective to energize said magnet.

Claim 7

A projector as defined in claim 5, wherein said switch serves also to control operation of said motor means to move said projection lens axially independently of said carriage.

Claim 8

A projector as defined in claim 1, wherein said coupling means includes a coupling member moving with said lens, and a friction member mounted on said carriage, said coupling member normally engaging said friction member to establish a coupling connection between said lens and said carriage and being disengageable from said friction member to render said coupling means ineffective.

Claim 9

A projector as defined in claim 7, wherein said coupling member is a pivoted lever having a wedge shaped portion for wedging engagement with said friction member, and said friction member is in the form of a non-rotatable tapering roller.

Claim 10

A projector as defined in claim 7, in which said coupling member is mounted on a slide movable parallel to said optical axis, further comprising a spring member tending to move said slide forwardly, and an abutment portion on said slide held in engagement with the mount of said lens by said spring, so that said slide is coupled to said lens to move therewith as the lens moves axially.

Claim 11

A projector as defined in claim 9, further comprising spring means tending to keep said coupling member engaged with said friction member, an electromagnet mounted on said slide and effective, when energized, to move said coupling member out of engagement with said friction member, and electric circuit means for energizing said electromagnet and concomitantly operating said motor means to move said projection lens axially.

Claim 12

In a slide projector comprising means for holding a picture slide in projection position, a projection lens member movable in the direction of its optical axis for projecting an image of said slide onto a viewing screen, a carriage member movable substantially in the direction of said optical axis, automatic focusing light beam projecting and receiving means including a part mounted on said carriage member to move therewith, and motor means controlled at least in part by said focusing light beam projecting and receiving means for moving said projection lens member axially, the improvement comprising: a driving element operatively connected to said lens member to move therwith when said lens member is moved axially by said motor means; a driven element operatively connected to said carriage member to cause movement of said carriage member substantially in the direction of said optical axis when said driven element is moved by said driving element; one of said elements being movable into and out of contact with the other of said elements to establish and disestablish a driving connection between said elements; spring means tending to hold said elements in position to establish a driving connection; and means including an electromagnet for moving one of said elements out of contact with the other of said elements against the force of said spring means, so that said motor means may move said lens member without exerting any force tending to move said carriage member, so long as said driven element is out of contact with said driving element, and may move said carriage member simultaneously with movement of said lens member, so long as said driving and driven elements are in effective driving contact with each other.

Claim 13

In a slide projector comprising means for holding a picture slide in projection position, a projection lens member movable in the direction of its optical axis for projecting an image of said slide onto a viewing screen, a carriage member movable substantially in the direction of said optical axis, automatic focusing light beam projecting and receiving means including a part mounted on said carriage member to move therewith, and motor means controlled at least in part by said focusing light beam projecting and receiving means for moving said projection lens member axially, the improvement comprising: a driving element operatively connected to said lens member to move therwith when said lens member is moved axially by said motor means; a driven element operatively connected to said carriage member to cause movement of said carriage member substantially in the direction of said optical axis when said driven element is moved by said driving element; one of said elements being movable into and out of contact with the other of said elements to establish and disestablish a driving connection between said elements; spring means tending to hold said elements in position to establish a driving connection; and means including an electromagnet for moving one of said elements out of contact with the other of said elements against the force of said spring means, so that said motor means may move said lens member without exerting any force tending to move said carriage member, so long as said driven element is out of contact with said driving element, and may move said carriage member simultaneously with movement of said lens member, so long as said driving and driven elements are in effective driving contact with each other.

Claim 14

The invention as defined in claim 11, wherein one of said elements is an elongated member extending in the general direction of said optical axis, and is pivoted to swing toward and away from the other of said elements, various portions of the length of said elongated member being engageable with the other of said elements, depending upon the spatial relationship of said lens member to said carriage member.