DE271254C - - Google Patents

Description

IMPERIAL

PATENT OFFICE.

PATENT LETTERING

- Λί 271254- CLASS 15 #. GROUP

in MEHLIS i.Thür.

Patented in the German Empire on January 9, 1913.

The known switch locks for typewriters are usually found two ratchet teeth arranged, which engage in the ratchet. These two ratchet teeth make a joint movement to the advancement of the ratchet wheel from one tooth to the other by one ratchet tooth at a time to enable. Both for the speed of writing and for the beauty the script, it is essential that the setting of the ratchet teeth can be regulated very precisely. However, this attitude has not been easy until now and only possible for experienced mechanics on most types.

A main purpose of the invention is to provide an arrangement in which this setting can be done easily. The innovation is that you have the two ratchet teeth arranged in such a way that they do not attack the same switching tooth, but rather two teeth, which form an angle of approximately 90 ° or more with one another.

Another purpose of the invention is to solve the problem of the two ratchet teeth to give a different speed, for example the fixed one Shift tooth a larger than the loose one.

The subject of the invention is shown in the drawing.

Fig. Ι shows the switch lock seen from the back of the typewriter,

Fig. 2 is a section through the ratchet axle,

3 shows a view of the ratchet wheel from the inside of the typewriter,

Fig. 4 is a view from above.

The shaft b is rotatably mounted between the grain tips α. Rigidly connected to this shaft is a cast body c, which carries both the loose shift tooth d and the fixed shift tooth β. The former (d) is mounted in such a way that its engagement surface lies in the center plane of the axis of rotation of the ratchet wheel, which is parallel to the axis of rotation b of the rocker c. The latter (e) is provided in a known manner with an inclined surface f in order to accelerate the sliding of the switching tooth after the type imprint has been made. The ratchet wheel g rotates on the shaft h and is driven by means of the gear wheel i from the rack, which is attached to the car in a known manner and is not shown in the drawing. The shaft b is set in oscillation by the arm m , likewise in a known manner, from the type lever that is moved in each case. In the rest position, one tooth of the gear wheel g rests on the loose shift tooth d , while the fixed shift tooth e (FIG. 2) is out of engagement with the shift gear g. If switching occurs by rotating the shaft b, the switching tooth d occurs outside the area of the gearwheel, and a tooth of the switching-

Claims (2)

wheel engages the fixed ratchet tooth e. Here, the loose shift tooth d is pulled up by a small amount by the spring k, so that it must now come into engagement with the following tooth of the peeling wheel when the shaft b executes its movement backwards and the ratchet wheel is thereby freed from the shift tooth e will. The new arrangement of the shift tooth e ίο now achieves the following: You can move the "shaft b axially" by adjusting the center points α without changing the height of the shift tooth d, as is readily apparent from the drawing Such a lateral shift changes the position of the indexing tooth e in relation to the indexing wheel g, in such a way that the tooth of the indexing wheel, which will come into engagement with the indexing tooth e during the next shift, suffers a greater or lesser fall 1 to the right, the horizontal position of the shift tooth d is not changed, but the shift tooth e is adjusted in such a way that the case of the tooth I interacting with the latter is increased that the switching tooth e due to its greater distance from the shaft b with each oscillation of the latter one makes greater movement than the shift tooth d, which is advantageous for the following reason: When the type lever returns from the pressure point, the shift wheel should be freed from the shift tooth as quickly as possible in order to initiate the next shift of the car without delay. This release happens all the faster, the faster the fixed switching tooth e moves back into its initial position. According to the present embodiment, this release occurs approximately twice as fast as if the shift tooth e were located next to the shift tooth d. On the other hand, it is more advantageous if the shift tooth d does not take part in the rapid movement, but rather moves away more slowly from the teeth of the ratchet wheel, since in the opposite case, there is easily an uncertainty in the shifting, d. H. a so-called runaway of the ratchet occurs. The innovation makes it possible to let one switching tooth move more slowly than the other. The result is an extremely fast shifting speed without impairing the safety of the same in the least. Godfather τ-An Proverbs: 1. Switch lock with a loose and a fixed tooth bearing and swinging rocker perpendicular to the ratchet wheel, characterized in that the shift teeth (d, e) such a position to the ratchet wheel (g) and the axis of rotation (b) of the rocker (c) have that the fixed tooth can be adjusted without changing the engagement of the loose tooth (d) by axially shifting the axis of rotation (b) of the rocker and the cooperation of the fixed tooth with the ratchet wheel takes place at a greater speed than that of the loose tooth. 2. Switch lock according to claim 1, characterized in that the shift teeth on the rocker (c) are mounted so that the engagement surface of the loose tooth (d) is in the axis of rotation (b) of the rocker parallel center plane of the axis of rotation of the ratchet wheel and the Fixed switching tooth is approximately perpendicular to the axis of rotation of the rocker and is on the opposite side of the ratchet wheel to the axis of rotation of the rocker. 1 sheet of drawings.