Abstract: A portable data processing device has a housing, a display, turnable holding arms arranged to hold the display above an upper side of the housing. Each of the holding arms has a holding arm-extension part provided with a blocking slider. The housing and the holding arm have locking recesses. The blocking slider has a first blocking portion which in one end position engaging in the locking recess of the holding arm and a second locking portion which in another end position engages in the locking recess of the housing. The blocking slider is spring biased in direction toward the locking opening of the holding arm and fixed in a locking position which is opposite to a spring force. The device also has a turning arm which locks the blocking slider in the locking position. The display is turnable and vertically movable between two different positions.

Abstract: A typewriter or similar machine with a ribbon and, if required, a correction tape on a pivotable support which can be lifted or lowered, the ribbon or the correction tape being movable in steps. The pivoting of the ribbon is necessary in order to give a view of the typed text. Since it is selectively possible to type or to correct, it is necessary to lift the support for the ribbon or the correction tape to different levels, so that the particular ribbon required is opposite the line to be printed. The transport of the ribbons as well as the lifting of the support is performed by means of a reciprocation-rotation motor. The respective rotational movement of the reciprocation-rotation motor is preferably transferred to one of the ribbons by toothed wheels. The ribbon can be moved on far enough so that a fresh ribbon surface is available. The same can be done for the correction tape.

Abstract: A holder of a ribbon with supply and take-up spools for typewriters and similar machines where the holder is insertable into a receptacle of the machine and has guide elements for the ribbon. The retention elements for the ribbon are designed so that the ribbon slides out of them when the side elements of the receptacle are pivoted back into their operational position. This assures on the one hand, that the ribbon is secured in a position during movement in the course of shipment which easily makes possible the insertion of the holder into the receptacle. On the other hand it is also assured that the ribbon is pushed out of these guidance elements during insertion of the holder into the receptacle and in this way attains its functionally correct position in the typewriter.

Abstract: In a line-spacing device for a typewriter or the like, where a platen, used as a support for the paper, is moved forward in steps by means of a ratchet it is provided for attaining a half-step transport that the gripper point (20) is seated longitudinally displaceable on the ratchet (11) in a direction approximately tangential to the toothed wheel (4) between two end positions determined by detent forces, where the detent force of the gripper point (20) is less than the force of resistance opposed by the toothed wheel (4) with the platen (1) to the drive by means of the gripper point (20) in the course of the tangential transport phase, and where the distance between the two detent end positions in the longitudinal direction corresponds to the tangential transport distance of a half transport step (t).

Abstract: A method of producing platens for typewriters and similar office equipment. Conventional platens often include a large number of individual parts and are relatively expensive because of their high assembly and finishing costs. According to the invention, an impact-resistant polyolefin with the addition of a delayed-reacting foaming agent is employed in an injection molding process in such a fashion that, by means of differential cooling of the mold, the material on the platen surface and in areas of other functional elements such as line-advance wheel/notched wheel combinations hardens, while the core of the platen remains a foam. The process allows platens with other functional elements molded to them to be manufactured from a single material in a single operation and without any additional work, despite different demands made on the print backing and the other functional elements.

Abstract: A housing for a paper shredder with a slit-like paper feed disposed on one side of the housing and a slit-like paper discharge disposed on the opposite side of the housing. The housing has an elongated shape, the dimension of length being a multiple of the dimension in width, where on each narrow side of the paper discharge support surfaces are disposed, with which the paper shredder can be placed on a waste receptacle. The width of the support surface is selected such, that one of the support surfaces is considerably larger than the width of the edge of the waste receptacle, while the other support surface has a width only negligibly greater than the width of the edge of the waste receptacle. It is additionally possible to provide a clamping device in the area of one support surface as security against sliding of the paper shredder placed on the waste receptacle.

Abstract: A receptacle for a holder of a ribbon of a typewriter or similar machine. The holder has a base plate on which laterally pivotable retaining elements are disposed. The retaining elements support drive, braking and tensioning elements for the ribbon. If the retaining elements are pivoted away, a holder, e.g. in the shape of a ribbon cassette, can be inserted into the device. When the retaining elements have again been pivoted back, they surround the holder of the ribbon in the form of a shell. The drive, braking and tensioning elements then automatically take up their functionally correct positions. The device has the advantage that only the holder with the used-up ribboon need be discarded, while the drive, braking and tensioning elements remain in the device and thus can be repeatedly used. Manufacture of the holder with the ribbon is made considerably more economical this way and the value of the material to be discarded is reduced.

Abstract: A holder for a ribbon for typewriters or similar machines where the holder is insertable into a receptacle. The holder must assume a firm and above all functionally correct connection with the receptacle. For this purpose two sliders with hook-shaped ends are disposed on pivotable side elements of the receptacle. These hooks embrace in their locking position edges provided on the ribbon guide arms. Only when the hooks are in their closed position can the combined device be inserted into the typewriter or the printer. The operationally correct insertion of the combined device would be prevented by a side element which is not closed or a protruding slider with its hook.

Abstract: In an electronically controlled typewriter, a printer or the like with an exchangeable ribbon cassette, which is provided with identifying codings and where the ribbon cassette is pivotable between a lowered position of rest and an elevated printing or operating position around the cassette base facing away from the printing area, it is provided in order to attain a simple and dependably readable coding which can discriminate between a plurality of different types of ribbon cassettes, that at a defined radial distance from the base of the ribbon cassette, which is to be inserted, a sensor is disposed at the side of the pivot path of the same, which gives off an electrical output signal in reference to a changing magnetic field. It is provided in a ribbon cassette for such a typewriter or such a printer to dispose at least one bistable magnetic element on a lateral surface of the ribbon cassette.

Abstract: A typewriter or similar machine having a platen turnable by means of a ratchet and a line spacing wheel and a carriage movable along the platen by means of a pulling means, on which a typing element or push button is disposed. In accordance with the invention a so-called lift-rotation motor is used for turning the platen, for line spacing and for moving the carriage. Its turning movement is transferred to the carriage by a pulling means. The axial movement of the motors causes the pivoting of a ratchet support on which the spacing ratchet is disposed which turns the platen by means of a toothed spacing wheel. In this way no additional motor for one of the two functions is required. The lift and rotary movement of the motor can take place temporally superimposed. In this way no time delays occur in the course of operation of the typewriter or of a printer.

Abstract: A typewriter or similar machine with a print wheel disposed on a shaft drivable by a motor, the characters of which are printed by means of a hammer. In accordance with the invention, use of a separate print magnet is to be omitted. This is made possible by the use of a lift-rotation motor. Its rotational movement is used for the rotational positioning of the print wheel, while the axial movement of the motor shaft is transferred to a print hammer pivotably disposed on the carriage. Determination of the engagement point of the motor shaft with the print hammer makes possible the optimum determination of the movement cycle of the print hammer as well as its print force. Thus the space above the motor for the print wheel, otherwise required for a print magnet, can be used for other purposes. Additionally there is a reduction of the masses which are required to be moved along the platen.

Abstract: A method of damping the rebound in print hammer magnets in typewriters or similar office machine in which kinetic energy is removed, in a manner known per se, from the armature of the print hammer magnet returning to its initial position by charging the coil of the print hammer magnet with a so-called braking pulse. The method provides the charging of the coil of the print hammer magnet with measuring pulses during the time when it returns into its initial position and to measure the current flowing through the coil. The increase in current depends on the width of the air gap and therefore permits conclusions as to the position of the armature, so that the braking impulse can be switched on at the correct time.

Abstract: A keyboard for typewriters or similar machines has a key support, switching contacts and key push rods, each of which is acted upon by a spring. The design of the few individual parts assures their simple manufacture (extruded parts and a stamped part) as well as an assembly just as simple and therefore automated, and, if desired, even without screws or aids of that type. Activation of the individual keys takes place with satisfactory tactile feedback and without undesireable vibrations.

Abstract: In a method for the operation of a typewriter, printer or the like with a stepping motor for the paper feed and a basic step inputting device, to accomplish feeding of the paper by a fraction of a line spacing, the feeding position set at the time of cutting off the machine is preserved by (1) storing the energization pattern last applied or information descriptive thereof in a value-preserving RAM at a first address, (2) storing a bit pattern contained in the control program in identical form at a second address of the value-preserving RAM, and (3) comparing the bit pattern of the control program which was stored in the second address of the RAM, when restarting the machine, with the bit pattern in the control program. The control program is stored preferably in a ROM of the central control unit, to verify as above the validity of the energization pattern stored in the RAM under the first address.

Abstract: In a typewriter having a microprocessor for processing stored data according to a stored program, a method for detecting that a machine cover has been opened for servicing and for interrupting a data processing cycle in progress for as long as the cover remains open, said method including, in response to said interruption, the steps of storing in a portion of memory all data, addresses and flags required for the later continuation of the control cycle so that the programmable control unit can subsequently be brought into a condition in which it is insensitive to a great extent to the consequences of electrostatic discharges as may occur during servicing, and after closure of said machine cover after servicing, reconstructing the status of the control cycle prior to the termination, by entering the data, addresses and flags stored in memory into appropriate working registers and buffers.

Abstract: Method for driving a picture tube and circuit assembly for executing the method. Video screens of recent construction have a thickness of the glass increasing towards the corners for reasons of mechanical stability, for this reason and because of the differing absorption of the emitted light through the glass, uneven illumination of the video screen results. For even illumination of the video screen a variable correction voltage is superimposed on the voltage difference at the electrodes of the picture tube which determine the beam current synchronously to the deflection of the cathode beam, the level of the correction voltage being automatically adjustable to the thickness of the glass at the respective location of the cathode beam. The drive method can be used for all picture tubes constructed in accordance with the construction principle mentioned.

Abstract: A method for automatically coupling a typewheel rotatably mounted in a cassette to a typewheel positioning shaft. After the insertion of the typewheel supporting cassette into a typewriter or printer, a coupling sequence is initiated under the control of a microprocessor. During the coupling sequence the typewheel positioning motor is driven to turn a clutch part first in one and then in another direction by a certain angle causing coupling projections on the clutch part to engage corresponding coupling slots on the typewheel. During the coupling sequence, the typewheel is prevented from co-rotating unintentionally due to its moment of inertia and due to active frictional forces.

Abstract: A ribbon cassette for electronically controlled typewriters or similar machines equipped with a signal generator, the ribbon cassette being disposed on a carriage moveable along the platen. The present invention is also directed to the combination of such a ribbon cassette with such a machine.

Abstract: A ribbon cassette with a memory makes it possible to provide a relatively exact determination of either the amount of ribbon remaining or the end of the ribbon with small mechanical outlay in an electronically controlled office machine or typewriter. A memory which contains external contacts and is capable of counting and storing values is provided from which base units can be subtracted by the control unit of the machine depending on the amount of ribbon advanced. The novel ribbon cassette makes it possible to dependably determine and display either the amount of ribbon remaining or the end of the ribbon.

Abstract: A ribbon and correction tape are separately mounted on a typewriter for movement in closely spaced parallel planes from a position below a line of impact along a line of print to an elevated position opposite said line of print. To minimize interference and malfunctions during relative movement of the ribbon and tape during elevating movement of one, the ribbon and tape are supported at an acute angle to one another, thereby to move in scissor fashion relative to the other.