DE176375C - - Google Patents

Description

IMPERIAL

PATENT OFFICE.

PATENT LETTERING

- M 176375 CLASS 15 d. GROUP

A. B. DICK COMPANY in CHICAGO.

Stencil drum.

. Patented in the German Empire on March 16, 1905.

The invention relates to a stencil printing machine with alternately vor- BEZW. reverse rotated stencil drum and consists in that the respective rotary movement the stencil drum is limited by a double-armed rocking lever whose Stop surfaces on both sides with a stop pin on the stencil drum in this way work together so that the same only after completion One complete forward or one complete backward rotation of 360 ° each to change the direction of rotation is forced.

The counter-pressure roller mounted below the stencil drum, which leads to the The stencil drum can be raised and lowered thanks to the double-armed Rocker arm outside of pushing against any movement with respect to the stencil drum locked as soon as the counter pressure

ao roller has taken the lowered position and only released when the stop pin the stencil drum back to the one stop surface after completing the reversing movement the rocker arm hits.

The invention is shown in the drawing, namely shows:

Fig. Ι a cross section through the stencil drum with the »rocker arm and the lock for the counter pressure roller,

Fig. 2 shows a detail,

3 shows a section along the line 3-3 in FIG. 1.

B is the stencil drum, I the counter-pressure roller, / ^s the stop pin on the stencil drum, which interacts with the rocker arm L.

The counterpressure roller I is mounted in the arms i , which are suspended at i ¹ on the inner surfaces of the side parts A, A ¹ (FIG. 3). The free ends i ^{2 of} the arms i, on which springs i ⁵ (Fig. 1) act, are directed downwards in a known manner (Fig. 2) and curved in order to grip under thumb discs i ³ , which are mounted on an oscillating shaft i * are attached. The shaft i ⁴ is also mounted in the side parts A, A ¹ and provided on the outside with a handle z ^e (FIG. 3). If the machine is to be put out of operation, the handle i ⁶ is rotated so that the thumb disks z ³ press the arms i downwards and consequently also the counter-pressure roller /, whereby it is removed from the stencil drum B.

The arms i carry rollers J, J, both of which lie in the movement path of curved pieces / z *, h ^{s attached to the stencil drum.} If the drum is rotated so far that the curve pieces / z ⁴ , /? ^{5 come} into contact with the rollers /, J , then the ^ e are pressed down and consequently also the counter-pressure roller /, which then comes out of contact with the stencil drum.

The rocker arms L, L are attached to / rotatably on the arms i between these and the side parts A, A ¹ . Each lever L ends at the bottom in a hook Z ¹ , at the top in a stop / ² .

As already indicated, these parts work together in such a way that when the drum is near the end of its printing movement, the cam pieces / z ⁴ and / z ⁵ press down the rollers J, J and thus the free ends of the arms i and the counter pressure roller / move away from the drum. Immediately thereafter, the stop pins Z ³ hit the upper ends Z ^{2 of} the lever L, so that these levers

ίο swing around their pivot points and bring ^{the ends Z 1} under the shaft z ^4. So hold the levers L, which are attached to the arms i and whose ends Z ^! reach under the shaft z ⁴ rotatable in fixed bearings, the arms i and the counter-pressure roller in the lowered position into which they were moved by the cams / j ⁴ , / z ⁵ ; the drum can then be moved back to its initial position while the back pressure roller is kept out of contact with it. At the end of this backward movement, the stops Z ³ hit the ends Z ^{2 of} the lever L again, on the opposite sides; the levers now swing around their pivot points until the ends Z ^{1 are moved} under the corrugation ⁴ . This triggers the arms i so that the springs i ⁵ can lift the free ends of the arms i in order to guide the pressure roller into the corresponding position relative to the drum, if. this movement is permitted by the cams / z ⁴ , / z ^5.

While the machine is in operation, the arms i carrying the counter-pressure roller / are out of contact with the thumb disks z ' ³ , since they are supposed to be pressed downwards by the action of the cams / j ⁴ , / z ⁵ on the rollers J, J. If as a result a gap has arisen between the counter-pressure roller and the stencil drum, a sheet of paper removed from the feed table M can be pushed into this in a known manner over the guides Ot. The stencil drum is then rotated in the direction indicated by the arrow (Fig. 2), the curve pieces / i ⁴ , / z ⁵ come out of contact with the rollers J, J, just before the stencil drum is to work together with the counter-pressure roller. The counter-pressure roller / now rises so that an impression is made on a sheet of paper.

This printing process lasts until the curve pieces / z ⁴ , Ir 'act again on the rollers /, J. This happens when the stencil sheet has passed through the counter-pressure roller. At this moment the curve pieces / z ⁴ , h '' press the pressure roller / downwards again, immediately afterwards the stops / ^{3 come} into contact with the ends / ^{2 of} the levers L, which swing around their pivot points Z and the curved ends Z ¹ bring under the shaft z ' ^4. As a result, the counter-pressure roller is locked again in its lowest position and kept out of contact with the stencil drum until it has returned to its starting point. The contact of the stops / ³ with the ends Z ² now leads the lever X back again so that they are released from the shaft i ⁴ , whereupon the same process is repeated.

Claims (2)

Patent Claims: 1. Stencil printing machine with alternately vor- or. Reverse rotated stencil drum, characterized in that the respective rotary movement of the stencil drum is limited by a double-armed rocking lever (L) , the stop surfaces of which on both sides interact with the stop pin on the stencil drum in such a way that the same only after completion of a complete forward or backward rotation of 360 each ° is forced to change the direction of rotation. 2. stencil printing machine according to claim ι with a pressure roller mounted below the stencil drum, which can be raised and lowered to the stencil drum, characterized in that the double-armed rocker arm (L) the pressure roller (I) against any movement .in relation to the stencil drum (B) Lock as soon as the pressure roller (I) has assumed the lowered position and only release it when the stop pins (I ^s ) of the stencil drum (B) hit the stop ends (P) of the rocker arm (L) after the stencil drum has completed the reverse movement . 1 sheet of drawings.