Rollei-werke Franke & Heidecke

Reinhard Sobotta

Dieter Mankau

A worm gear mount of a type used in slide projectors includes a shaft, a pair of bearings supporting the shaft, a drive wheel on an end overhang of the shaft extending beyond one of the bearings, a worm gear on the shaft betweeen the bearings, and a gear wheel rotatable on an axis perpendicular to the shaft and meshing with the worm gear. The bearings are formed with generally U-shaped openings that face toward the gear wheel, and the openings allow the shaft to be moved into the bearings from the region occupied by the gear wheel. The gear wheel serves to prevent movement of the shaft out of the openings, and the openings are preferably shaped so that the shaft has a snap fit in the bearings. The shaft is also preferably formed with reduced diameter journal portions fitting in the bearings to prevent axial movement of the shaft.

Worm gear mount

A slide projector having a remote control unit which is removable engageable with the slide projector. When the control unit is disengaged from the projector, it is removably engageable with an accessory which can be a further control or indicating device. Electrical contacts on the control unit electrically communicate with contacts in an aperture located on the projector and also a similar aperture located on the accessory. Thus, during remote control operations, an additional function or indication can easily be added to the control unit.

Removable remote control unit for a slide projector

A still projector with a magazine guide channel, a projection lens, and a manual electrical switch has a cover that encloses all these components and fits closely in a recess in the housing. The cover is preferably shaped to fit the external contour of the housing and has a first plate covering the projection lens and one end of the magazine channel, a second plate covering a switch and the other end of the magazine channel, and a panel extending between the two plates and covering the top of the magazine channel.

Still projector with cover

A slide projector having resilient flexible elements mounted on the projector to engage the edges of slides in magazine compartments next to the compartment from which a slide is to be withdrawn or to which a projected slide is to be returned, for shifting the slides in the adjacent compartments to upright positions flat against the partition walls of the magazine, so that they will not tilt to positions overlying the compartment from which a slide is to be withdrawn or to which it is to be returned, thus avoiding possible interference with the withdrawal or return.

Photographic slide projector

A double slide projector having two slide projection assemblies, a common magazine for slides, and a common slide changer, uses a motion transmitting arrangement from a drive to the changer so that the changer is moved a full stroke for moving slides from the magazine to the more remote projection assembly and the changer motion is blocked at a partial stroke for movement of slides from the magazine to the nearer projection assembly. A drive provides sufficient movement to move the changer for a full stroke for each actuation, and a slip clutch is arranged in the motion transmitting device so that the changer can move alternately between a full-stroke and a blocked or partial-stroke position. A double-track cam is preferred for the drive, and an arrangement of levers connected through the slip clutch is preferred for transmitting motion from the cam to the gripper portion of the slide changer.

Dual photographic slide projector

A still projector having a closure plate covering a housing aperture providing access to a projection lamp has a storage chamber within the housing positioned to be covered by the closure plate when the closure plate closes the aperture and to be accessible when the closure plate is removed from the aperture. The storage chamber is shaped to receive and store a spare projection lamp and preferably also a lamp changing tool. The closure plate is preferably a slide plate fitting flush with an exterior surface of the housing and extending over a cooling fan and its drive motor. The closure plate prefereably has air passage slots located over the fan, and the storage chamber is preferably formed as a depression in the projector housing over the drive motor.

Still projector with spare projection lamp

A magazine-type slide projector has a single slide projection accessory that is removably placeable across the magazine track. The accessory has a slide compartment positioned on the slide changing plane, and the compartment has an open top edge and an open side edge facing the slide projection position. The accessory allows manual insertion and removal of single slides through the top opening of the compartment for movement of the slides into and out of the slide projection position by the slide changing device. The projector also preferably has a storage compartment where the accessory can be conveniently stored when not in use.

Slide projector for both magazine and single slide projection

A two-part circular magazine having an inner rotor with slide storing compartments and an outer stator enclosing the rotor is arranged to mount and operate in the magazine guide of a linear magazine slide projector. The stator has a tangential groove opening to the rotor in the region of a radial slot for transverse passage of a slide from the magazine, and the groove has side walls that fit opposite sides of a slide lifting ramp in the bottom of the magazine guide. The rotor exterior is positioned directly over the top of the lifting ramp when the magazine is mounted in the projector, and the stator has an inclined surface ascending from below the top of the lifting ramp upward to the level of the interior of the rotor in the region of the slot. The stator also has abutment surfaces that engage parts of the magazine guide to position and maintain the magazine accurately in place.

Circular magazine for linear magazine slide projectors

A cam and follower construction in which a flat plate has a plurality of cam grooves intersecting each other and in which the cam followers are in the form of cylindrical pins or rollers, one in each cam groove. To insure that each follower stays in its own groove and does not accidentally pass into the wrong groove at the point where they intersect, the grooves are made of different widths and different depth, the widest groove having the shallowest depth and the narrower groove having a greater depth. Thus the follower of a wide cam groove cannot pass into an intersecting narrower groove because the groove is too narrow to receive the follower, and the follower of the narrower groove cannot pass into the wider groove at the intersection, because the narrower groove is deeper and the shallower wide groove cannot accommodate it. In a modification of the construction, all of the cam grooves may have the same width near the surface of the cam plate, cooperating with follower pins or rollers of the same diameter, one groove being of a certain depth, the other grooves having a main part of lesser depth but a supplementary deeper groove receiving a guide pin extension on the follower, which serves to prevent the follower from accidently entering the wrong cam groove where the grooves intersect.

Flat curve cam and follower construction

Mechanism for feeding a picture slide magazine in such a way that picture slides can be taken out of the magazine in the same order in which they are placed in the magazine, for delivery to two separate projector units of a dual slide projector, and then can be returned to the magazine still in proper order. Two indexing gears rotate in opposite directions about a common axis of rotation. Each gear carries index pins or projections which cooperate with a star wheel or modified Geneva gear as the indexing gears rotate, and the star wheel or Geneva gear drives two pinions which engage a toothed rack on the slide magazine. As two indexing pins located relatively close to each other on one indexing gear pass the star wheel, they rotate the star wheel through two increments, to feed the magazine through two steps in one direction. As a single pin on the other indexing gear moves past the star wheel in the opposite direction, it turns the star wheel through one increment in the opposite direction, thus feeding the magazine through one step in the opposite direction. Thus the magazine is moved with the 'pilgrim step' movement necessary when picture slides from a single magazine are to be projected alternately in two separate projector units and are then to be returned in proper order to the original magazine.

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Brunswick, Germany

Reinhard Sobotta