Hermes Precisa International S.a.

Hermes Precisa International

Gustave Gagnebin

A pivotal rod, in the form of a flat bar, extends through an axial bore of a sleeve, pivotally mounted on a sliding carriage. A coupling member connecting the rod to the sleeve comprises a slide pivoted on the sleeve around a pivotal axis perpendicular to the axis of rotation of the sleeve and sliding along the rod. The coupling member includes three ball bearings, two of which bear on the edges of one of the surfaces of the flat bar and the third bears against the other surface in the longitudinal axis of the flat bar. The bearings are mounted on pivots oriented parallel to the pivotal axis of the coupling member. This mechanism ensures an angular coupling without play between the rod and the sleeve and is usable even when the displacement of the rod or the trajectory of the carriage or their parallelism to each other is not perfect.

Coupling mechanism

A cassette comprises a casing (1) containing a delivery spool (2) and a receiving spool (4) co-operating with drive means. The ribbon (3) passes from the delivery spool (2) to the receiving spool (4) outside the casing (1). The delivery spool (2) is secured to a toothed wheel (20) which co-operates with a catch (23) of a part (21) biased by a spring (28). This part (21) in the form of a T, is pivotally mounted on the casing (1) at one of the upper ends of the arm or crosspiece of the T and carries return roller (24) at the other end of this arm around which roller the ribbon (3) is diverted in a manner to form a loop. The length of the upper arm of the part (21) is substantially twice as large as the distance separating the catch (23) of the pivot point of the part (21). This arrangement ensures a correct tension of the ribbon ( 3) at all times.

Ribbon cassette for typewriter with tension producing locking device

A printing disc (1) is applied by a leaf spring (9) against a plate (6), provided with projections (14), of a support (2). These projections (14) lock the printing disc (1) in a predetermined position in the support (2). This support (2) is provided to be introduced in a typewriter transversely to the selecting shaft (15) between the driving plate (18) and the card press (16) the two folded over borders (23) of which form lateral guides. Two slots (26) of these borders (23) form abutments for bosses (25) of the support (2). The support (2) has an opening (8) opposite the hub (3), the engagement of the hub (3) of the disc (1) on the driving plate (18) is effected by pivoting the support (2) in the direction of the selecting shaft (15). The driving plate (18) passes through the opening (8) and holds the printing disc (1) spaced apart from the projections (14). This device is light and permits the mounting of the disc (1) without having to displace the selecting shaft (15).

Device for installing and securing a printing disc

The tabulator blade rack consists of a pivotally and axially movable rod. Depressing the desired decimal tabulation key frees the carriage from the escapement for movement in the typing direction, raises the corresponding tabulator stop, and rotates the tabulator rack and the blades thereon. Operation of the set and clear key sets a blade; the carriage moves, striking a projection on the set blade, thereby shifting the rack to the right until a stop thereon hits the raised tabulator stop, stopping the carriage at the corresponding position. When the rack stop hits the tabulator stop, the consequent movement of a rod that mounts the latter causes the raised tabulator stop to be lowered, the return of the rack, both longitudinally and rotationally, to its rest position, and the carriage to be reengaged with the escapement at the chosen tabulating position.

Growing community of inventors

Yverdon, Switzerland

Gustave Gagnebin