DE2114273C3 - Type lever drive device for power-driven typewriters and similar office machines - Google Patents

Description

task

The invention is based on the problem of proper coupling and uncoupling of the drive pawl To ensure avoidance of repercussions from the coupling process. This task becomes solved with the invention characterized in claim.

benefits

The coupling and uncoupling of the coupling pawl with the revolving drive toothed shaft takes place at the subject of our invention largely seamless. This has a very beneficial effect on the one hand Wear and the noise and on the other hand enables a typeface with uniform intensity, without the need for additional parts.

Explanation of the invention

The invention is explained in more detail using an exemplary embodiment. It shows

F i g. 1 shows a section through a typewriter with the subject matter of the invention,

Fig.2 the coupling of the coupling knees with the Drive shaft and

F i g. 3 the uncoupling of the coupling pawl with the drive shaft.

The drive of the individual type lever gears, only one of which is shown in the drawing, takes place from a toothed drive shaft 1 with z. B. four through teeth 3, 5, 7, 9. These teeth 3, 5, 7,9 cooperate with a stop lug 11 of a coupling pawl 13, which is connected via a pin-slot connection extension 15, 17 is connected to a two-armed intermediate lever 19. The intermediate lever 19 is in the frame 21 mounted on an axis 23 and via a pull wire 25 with one on an axis 27 in the type lever segment 29 mounted type lever 31 connected. The type lever 31 is provided with a type block 33 with types 35.

Between the coupling pawl 13 and a key lever 39 mounted on a shaft 37 fixed to the frame with button 41 a spring 43 is attached, which is used to reset the type lever mechanism and the button lever 39 serves. The key lever 39 is in the starting position with a stop edge 45 on a frame fixed Rail 47 on. The coupling pawl 13 is through the

35

Spring 43 outside the effective area of the rotating drive shaft 1 and rests against a ridge 50 with a stop surface 49. The key lever 39 is guided in a second comb 51 and acts via a control lug 53 with the first A ischlagnase II of the Coupling pawl 13 together. This coupling pawl 13 also has a second stop lug 55 which is arranged as an adjustable prong 59 of the coupling pawl 13. This second stop lug 59 also acts with di.ii teeth 3, 5, 7, 9 of the drive shaft 1 together. The key depth of the key lever 39 is determined by its stop lug 61 and a counter stop 63 limited in Kfcmm 51. The mode of operation of the subject matter of the invention is as follows:

When the button lever 39 is actuated, the coupling pawl 13 is brought with its first stop lug 11 over the control lug 53 in the effective area of the tooth 5 of the drive shaft 1, see Fig. 2. Hbrbei only the coupling pawl 13, which is spring-loaded by the spring 43, is taken along, which is controlled via the pin-and-slot connection 15, 17 at an angle to the guide comb 50 so that the first stop lug 11 inevitably reaches the stop 12 with the driving tooth 5 is engaged. F i g. 3. This always gives the type lever gear an even initial acceleration. When the coupling pawl 13 reaches the stop position and the pin 15 has passed through the slot 17, the type lever gear 19, 25, 31 is taken along and accelerated. Via the pin-and-slot connection 15, 17 and the arrangement of the hinge points of the links of the type lever gear 19, 25, 31 in the vicinity of the route, the impact that occurs when coupling the coupling pawl 13 and drive shaft 1 no longer has a harmful effect on the type imprint. The type lever gear is accelerated until the second

(f

Stop lug 59 inevitably> n operative connection closed which the type lever gear 19,25,31 in the stop direction «The rubbing tooth 5 immediately following the next tooth 7 of the drive shaft t reaches the first stop lug 11 perpendicular to its drive direction v <Jn to decouple the driving tooth 5, see Fig. 3. This causes a recoil acceleration on the type lever gear avoided.

The adjustable prong 59 means that the coupling pawl 13 and the drive shaft are uncoupled 1 and thus the imprint strength of the individual type lever gears can be precisely adjusted. For small areas The prong 59 becomes letters very early with the next immediately following the driving tooth Tooth come into contact, while with large characters the decoupling takes place as late as possible got to.

The adjustment can be done with simple tools and only once either in normal or in the switching position can be made, what the claims in particular of small typewriters corresponds perfectly.

The regulation of the velocity at different Penetration can z. B. by regulating the speeds of the drive shaft 1.

The invention is characterized by a simple and cheap design with which a good quality Typeface can be achieved. Thanks to the low-impact coupling and uncoupling of the coupling pawl 13 and drive shaft 1 recoil accelerations are avoided on the Typer.hebelantrieb 19, 25, 31, which are can have a detrimental effect on the typeface. In addition, the adjustable prong 59 is an inexpensive and easy to use adjustment of the imprint strength given.

1 sheet of drawings

Claims (1)

Claim: Type lever drive device for power-driven typewriters or similar office machines with a rotating toothed drive shaft, in the effective area of which one on an intermediate lever of the Type lever gear mounted coupling pawl can be brought when a button is pressed, a first Stop lug for coupling with the drive shaft and a second stop lug for uncoupling the drive shaft are arranged on the coupling pawl in such a way that the second stop lug inevitably comes into operative connection with that tooth of the drive shaft, which the Type lever gear immediately follows the driving tooth in the stop direction, the first stop lug is decoupled from the driving tooth perpendicular to its drive direction, characterized in that that the adjustable prong (59) designed as a second stop lug made of spring band steel and that the slot of the coupling pawl (13) with the intermediate lever (19) connecting pin-slot connection (15,17) so obliquely to the direction of movement of the coupling pawl (13) extends so that the first stop lug (11) of the coupling pawl (13) resting with a stop surface (49) on a guide comb (50) inevitably engages the driving tooth (3) up to a stop (12) ″ of the coupling pawl (13) can be brought. The invention relates to a type lever drive device for power-driven writing and the like Office machines of the type specified in the preamble of the claim. State of the art In a type lever drive device made known by the patent specification DT-PS 1203 802 When a key lever is operated, a drive pawl rotatably mounted on an intermediate lever is included brought a first stop lug into engagement with the teeth of a drive shaft. The clutch of the drive pawl with the constantly rotating drive shaft, this does not take place smoothly. To the type lever gear To give the energy required to print the corresponding character area is the Drive pawl is decoupled via a stop lug that interacts with an adjustable counter-stop. The sudden stop of the drive pawl causes the type lever action to run through the kinetic one Energy continues through and swings the stop lug of the drive pawl out of the drive shaft. With this one Decoupling is a recoil acceleration on the type lever gear can not be avoided, which is very has a detrimental effect on the type imprint. The intensity of the type prints is very different. Furthermore, a type lever drive device is through the US-PS 22 17 179 known, in which a first stop lug for coupling to the drive shaft and a second stop lug on a coupling pawl for decoupling from the drive shaft arranged such that the second stop lug inevitably in Active connection with the immediately following tooth driving the type lever gear in the stop direction The next tooth of the drive shaft arrives at the first stop lug perpendicular to its drive direction to decouple from the driving tooth. This inevitable uncoupling takes place for all clutch pawls after a drive path of the type lever gear of about 45 °. The type lever gears all receive the same power from the drive shaft and must then be caught in free flight according to the character area on the type blocks, to get an even impression. This interception of the type lever gear is not entirely possible bounce-free in front of it and leads to fluctuations in energy, the different intensities of the type prints entail. In addition, there is a separate device with additional devices for regulating the thickness of the impression Sharing required.