FR2536341A1 - DEVICE FOR GUIDING AN INK RIBBON IN A LINE PRINTER - Google Patents

Abstract

A DEVICE FOR GUIDING AN INK RIBBON IN A PRINTER, IN WHICH THE RIBBON 14 IS GUIDED THROUGH THE ENTIRE EXTENT OF THE LINES, IS CONSTITUTED BY A SUPPORT FIXED IN FRONT OF THE PRINTING DEVICE 10 AND ON WHICH ARE PROVIDED BY SIDE AND ON THE OTHER OF THE PRINTING DEVICE 10 AND IN A MANNER TO BE AT LEAST PARTIALLY OFFSET BACK TO THE PLANE OF THE ANTERIOR SIDE OF THIS LAST TWO ELEMENTS 21, 22 FORMING GUIDING SURFACES, WHICH ARE OBLICALLY ARRANGED WITH RESPECT TO THE DIRECTION OF THE LINES. A GUIDING ELEMENT 20 IS ABOVE THE LEVEL OF THE LINES GUIDES THE RIBBON 14, WHEN IT IS PLACED IN THE PRINTER, IN FRONT OF THE ELEMENTS 21, 22. SINCE THE latter HAVE CURVED SIDE EDGES, THE RIBBON 14 SLIDES, WHEN THE PRINTING DEVICE IS BROUGHT INTO ANY OF THE RIBBON DEVIATION ZONES, AT THE END OF THE EXTENT OF THE LINES, OVER ELEMENTS 21, 22 TO OCCUPY THE GUIDING POSITION WANTED BEHIND THESE LATEST.

Description

i

  Device for guiding an inked ribbon in a printer

by lines.

  The present invention relates to a device for guiding an inked ribbon in a line printer equipped with a movable printing device in the

  direction of the lines and which presents, on its anterior side

  eur facing the recording medium to be printed, guiding elements for the tape passing over the extent of the lines and deflected at the ends of the extent of the lines in a direction substantially transverse to the direction

lines.

  Printers in which devices of this type are used most often operate with a ribbon cassette which has an inlet and an outlet for the ribbon, which assume the shape of arms projecting forward and are located one by one. compared to

  the other at a distance corresponding to the length of a line

  printing gne Ribbon cassettes of this kind are placed from above in the printer so that the ribbon extends between their entry and exit substantially in

  the direction of the lines and this is about allowing

  be on the ribbon to come and occupy as much as possible without

  be manual intervention or complication, the position

  read where it extends in the direction of the lines between a dis-

  positive printing, for example a printhead

  needles, and the recording medium guided on a bar-

  re writing, so that when the print organs

  Zion needles act on the back side of the ribbon,

  the ink thereof is transferred to the recording medium

  registration. When during the printing process the printing device moves inside the printer in the direction of the lines it is necessary, in this case concerns this

  movement relative to the ribbon extending in front of the device

  tif printing in the direction of the lines, provide a ribbon guide which ensures that the ribbon is supported on the front side of the printing device in an optimal position for the transfer of the ink, whatever either the position of the printing device A

  this end is provided at the anterior side of the arrangement

  sitive printing guiding elements that allow

  the ribbon, which is guided along the relatively short length

  bearing the line without being supported, to be guided by resting on the printing device itself and

  to be maintained, regardless of the position of the latter

  deny, at the level of a line and each time in the posi-

  optimal guiding elements capable of ensuring

  this state of affairs has so far been of a construction

  tion relatively complicated so that when placing the ribbon in a printer there was always a long and laborious threading work during which we also inevitably dirty hands O

  The object of the present invention is to indicate a provision

  sitive intended to guide an inked ribbon and enabling it

  ci to be automatically put on after being put on

  this from above in the area between the imager

  pressure and the recording medium.

  This object is achieved according to the invention, for a provision

  sitive of the kind mentioned above, by the fact that the ele-

  guide elements are arranged on either side of the arrangement

  printing position so as to be offset at least partially-

  behind the plane on the front side and each have a part forming a surface for the inked ribbon

  guide extending obliquely to the direction

  tion of the lines and oriented towards the printing device, which part forming a guide surface is present on the side

  away from the printing device a convex or oblique edge

that located next to the ribbon.

  The invention makes it possible to put an inked ribbon in place from above in a printer without having to thread it

  between the guide elements by a particular manipulation

  By being introduced from above into the area located

  be the printing device and the recording medium

  The ribbon is placed on the front side of the elements forming guide surfaces for the ribbon which are at least partially offset backwards from the plane of the front side of the printing device.

  the printing device is then transported in the direction

  tion of the lines and arrives at the left or right end of the extent of the line, o in the case of a printer of the type envisaged in this case the ribbon is deflected approximately transversely to the direction of the lines, said part of the guide surface element arrives with its

  convex edge, located opposite the ribbon, in the area of

  viation where it abuts against the deflected ribbon, During the subsequent transport movement of the printing device, the ribbon

  can then slide upwards on the convex edge of the

  element forming a guide surface until, as a result

  of its increased tension caused by the movement of trans-

  port of the printing device it slides past the edge

  the upper part of the guide surface and is placed

  this behind it where it occupies the desired guide position in which it is maintained on the anterior c 8 tee

  of the printing device through the orienting surface

  When the printer is then transported in the opposite direction to the other end of the line extent, the unwinding

  of the process described is ensured on the other side of the device-

  printing by the element forming the guide surface provided on this side, in particular the convex edge thereof, so that the ribbon is then also correctly guided on the other side of the printing device. , after placing the ribbon in the printer, carry out a double transport movement towards one and

  the other end of the extent of the line Such a movement

  transport is necessary anyway to

  ner the printing device in a well-defined starting position at one end of the line extent. Advantageously, the device is constructed so

  that above the level of the lines is a form element

  mant guiding surface which, when placed from above, guides the ribbon along its anterior side in front of each of the elements forming guiding surfaces on the side

  prior to these diverted from the printing device.

  Such an element forming a guiding surface for the ribbon is particularly advantageous in the case of printers where a long length of lines is provided and the ribbon risks, during the positioning, of forming loops due to the crossing of this great length. , so that if necessary, instead of being brought first in front of the two elements forming guide surfaces by the movement of

  put in place, it is wrongly introduced between these elements

  elements and the printing device In order to avoid this, the additional element forming the guiding surface for the ribbon makes it possible, even in the case of an inattentive positioning movement, to always obtain suddenly that the ribbon is placed first on the anterior side of the elements forming the guide surfaces, so that the convex edges of these then allow the tape to be brought into the desired position behind the elements forming the guide surfaces. An exemplary embodiment of the invention is described below with the aid of the appended drawings in which: FIG. 1 is a schematic top view of a printing device guided in a printer and with which is associated a cassette containing an inked ribbon FIG. 2 partially represents the guide elements for the ribbon in a first service position FIG. 3 partially represents the guide elements for the ribbon in another service position;

  FIG. 4 is a rear view of the guide elements.

  tape dage; and FIG. 5 represents the guide elements for the ribbon observed as indicated by A-A in FIG. 4, the

ribbon having been threaded.

  In Figure 1 is shown a device for im-

  pressure 10 able to move back and forth

  comes on a guide bar 11 inside a printer

  mantis which for the rest is not shown The guide bar 11 is retained in two lateral plates 12 and 13 of the printer The printing device 10 is in the present embodiment a printing head with

  needles of a type known per se which at the level of its

  -mity located at the top in Figure 1 acts with its printing needles on an inked ribbon 14 so that it can transfer its printing ink on a recording medium not shown in Figure 1 The ribbon 14 is , in a manner known per se, disposed in a supply cassette 15 which has guide arms 16 and 17 projecting from its body and between which the ribbon 14 is guided so as to enter a guide arm and to exit the other guide arm The distance between the two guide arms 16 and 17 corresponds to the length

  a line to be printed with the printer, the print head

  needle zion 10 moving for this purpose with a movement

  back and forth on the guide bar 11 in the area between

  be the two guide arms 16 and 17.

  When the cassette 15 is placed from above

  in the printer it is a question of the ribbon 14 coming to be used

  for a specific position in front of the print head

  needle 10 and stay there during the back-and-forth movement

  comes from the needle print head 10, so as to obtain

  always hold an optimal print, whatever the position of the needle print head 10 For this purpose there is provided for the ribbon a guide device 18 which is fixed by means of screws 19 to the needle print head 10 and has an upper element 20 forming

  directing surface for the ribbon as well as elements

  sides 21 and 22 forming guide surfaces for the ribbon which are arranged on either side of the needle print head 10 The mode of operation of these elements

  when threading the ribbon is explained in more detail below

  below using figures 2 to 5.

  Figures 2, 3 and 5 show views

  from above of the guide device 18 without the upper element

  laughing 20 forming directing surface for the ribbon, a partial section along line A-A of FIG. 4 being each

  times shown for this purpose The edges of the tape 14 are shown

  felt in phantom in Figures 2 to 5.

  FIG. 2 shows the lower part of the guide device 18 comprising two forked legs 23, also visible in FIG. 1, which serve for its attachment to the needle print head 10 (FIG. 1) The device

  guide 18 comprises a body 24 made so as to pre-

  feel several faces making angles between them, in a manner corresponding to near the c 8 anterior tee of the needle print head 10, and comprises on the lower side two overhangs 25 and 26 projecting to the left

  and to the right and on which elements 21 and 22 form

  the guide surfaces for the tape are mounted upright in the form of two-part guide bars The guide bars consist of two parts 21 a, 21 b and 22 a, 22 b which are respectively arranged so as to make angles between them, the parts 21 a and 22 a being

  inclined to the direction of the lines and the

  ties 21 b and 22 b being parallel to this direction.

  The representation of Figure 3 corresponds to that of Figure 2 but relates to another service position

  which will be further explained in detail later.

  FIG. 4 is a rear view of the guide device.

  dage observed on the side of the needle print head 10

  (figure 1) In figure 4 the construction of the device appears

  positive guide 18, as already described with the help of FIG. 2, that is to say in the form of a body 24 partially surrounding the anterior end of the t 5 te

  needle printing 10 and from which both pat-

  your 23 protrudes backwards In the front side

  of the body 24 a window 27 is further observed through the

  which the needles of the print head can act on the upper half of the ribbon 14 Above the body 24 carries the element 20 forming a guiding surface for the ribbon and which has a left arm 20 a and a right arm 20 b Both arms 20 a and 20 b are inclined downwards from the

  center of element 20 forming directing surface and present

  tent, as shown in Figure 1, also a slight in-

backward tilt.

  The elements 21 and 22 forming guide surfaces for the ribbon are shown in FIG. 4 so that

  show the shape of their edges The outer edge,

  that is, the diverted edge of the needle print head (FIG. 1) of each of these elements is convex as shown in FIG. 4 The outer edges of the parts 21 b and 22 b forming guide surfaces for the ribbon are designated respectively by 21 c and 22 c in FIG. 4 FIG. 4 shows the ribbon 14 in the already threaded position where it is located in front of the body 24 of the device.

  guide frame 18 but behind elements 21 and 22 form

  mant guide surfaces for the tape.

  The same state of affairs is shown in top view in FIG. 5 where it can be seen that the strip 14 is located behind the elements 21 and 22 forming guide surfaces,

  so that it is partially guided around the c 8 ante-

  laughter of the needle printing head 10 (FIG. 1) and remains in this position when the needle printing head 10 moves with the guide device 18 back and forth in the direction shown

  in Figure 5 by a double arrow.

  The following is now described how the ribbon 14 is

  automatically threaded to occupy the position shown

  felt in Figures 4 and 5 Figure 2 indicates by an arrow the movement of the guide device 18 to the right, the guide device 18 then arriving in a position at the right end of the extent of the line o the tape 14, as shown in FIG. 1, is deflected backwards After the cassette 15 has been put in place, the tape 14 is first guided on the element 20 forming a guiding surface, in front of the elements 21 and 22 forming the guidance This position is shown in Figure 2 in

  top view When the guide device 18 moves

  this towards the right in the direction of the arrow shown in FIG. 2 and arrives in the zone of deflection of the ribbon 14,

  the curved edge of part 22 b of element 22 forming a

  guide face abuts against the ribbon and has the effect, because of its curved shape, that the ribbon is placed at an angle, as indicated in FIG. 2 by an arrangement spread as a consequence of the ribbon 14 with its edges 14 a and 14 b If the guide device 18 now moves even more

  to the right, then the ribbon 14 slides on the upper edge

  eur 22 d, visible in FIG. 4, of the element 22 forming

  guide surface, until the ribbon 14 arrives behind

  part 22 a of element 22 forming a guide surface

  dage so as to be in the position shown on

Figures 4 and 5.

  The same process takes place when the guide device 18 is moved according to FIG. 3, in the direction of the arrow shown thereon, to the left In

  in this case the guide device 18 arrives at the left end

  che of the extent of the line where the guide arm is placed

  dage 16 of the cassette 15 (figure 1) As a result of the movement

  later to the left the ribbon 14 is placed, as shown in FIG. 3, on the element 21 forming the surface

  guide, which is indicated by a corresponding provision

  laying down of the two edges 14 a and 14 b of the ribbon 14 Finally, the ribbon 14 then slides behind the element 21 forming the surface

  guide, so that on the left side of the print head

  needle pressure 10 (figure 1) it is also found

guided into the correct position.

  To thread the ribbon 14, it suffices to put the cassette 15 in place from above in the printer so as to bring the ribbon 14 in front of the upper element 20 forming a directing surface. Then the needle print head 10, at which the guide device 18 is fixed, must be

  moved once to the left and to the right and this res-

  pectively to the end of the line extent, after which the automatic threading process is finished

  and the print job can be started convenient-

is lying.

  The invention is not limited to the use,

  above, of a needle printing device

  in combination with a tape cassette It is aprli-

  cable in all cases where the ribbon is guided over the extent of the lines and a movable printing device must, within the extent of the lines, during its transport movement guide the ribbon in a well-defined position ; It is thus for example conceivable to put the invention

  also used in the case of printers which do not use

  feels no ribbon cassettes but ribbon spools arranged on the left and right The printing device is not necessarily a needle print head; on the contrary, it can also be provided for example a printing device with a character wheel or another

  movable character printing device

due lines.

  Elements 21 and 22 forming guide surfaces

  have been described above as bars of mistletoe

  dage in two parts whose parts are arranged at an angle to each other and, as in the figures

  show it, enclose an obtuse angle between them.

  rait also to provide only elements forming surface-

  these guide lines corresponding to parts 21 a and 22 a, in which case these should then have the convex edge on the side turned away from the needle print head 10 the degree of curvature of this edge is not critical. It could also be provided an edge extending obliquely, as shown for example in Figure 4 for the edges

  interior of elements 21 and 22 forming guide surfaces.

  the whole of the guide device 18, including the lugs 19, the overhangs 25, 26 as well as the upper element 20 forming a guiding surface for the ribbon, can be produced in one piece and be produced for example by

  synthetic material by an injection molding process.

  The distance of the two free ends of the arms 20 a and 20 b of the element 20 forming the directing surface to the upper edges of the elements 21 and 22 forming the guiding surfaces is not critical. It must however be sufficiently

  large so that the ribbon 14, sliding on the upper edges

  laughing elements 21 and 22 forming guide surfaces, 1 1 can pass unimpeded in the space behind these elements.

Claims (5)

  1 Device for guiding an inked ribbon in a line printer equipped with a printing device movable in the direction of the lines and which has, on its anterior side facing the recording medium to be printed, guiding elements for the ribbon passing over the extent of the lines and deflected at the ends of   the extent of the lines in a substantially transverse direction   transverse to the direction of the lines, characterized in that the guide elements (21, 22) are arranged on either side of the printing device (10) so as to be offset at least partially behind the plane on the anterior side and respectively have a part   (21 a, 22 a) forming a guide surface for the inked ribbon   dage extending obliquely to the direction of the lines   genes and oriented towards the printing device (10), which part forming a guide surface has a convex or oblique edge on the side 8 away from the printing device (10)   (21 c, 22 c) located opposite the ribbon (14).   2 Device according to claim 1, characterized in that above the level of the lines there is an element (20) forming a directing surface which, when the   place from above, guide the ribbon (14) along its an-   in front of the part (21a, 22a) of the respective elements forming guide surfaces, on the anterior c 8 of this   diverted part of the printing device (10).   3 Device according to claim 2, characterized   in that the part (21 a, 22 a) of the respective elements form   mant guide surfaces is part of a guide bar   dage (21, 22) in two parts, the second part (21 b, 22 b) of which extends roughly parallel to the direction of the lines, made with the first part (21 a, 22 a) at an angle   obtuse and presents the curved or oblique edge (21 c, 22 c).   4 Device according to claim 1, 2 or 3, ca-   characterized in that the guide surface for the ribbon   created is provided on a steering element (20) with two arms, the arms (20 a, 20 b) of which extend from a place situated above the printing device (10) near the anterior side of this laterally and tilted down to end at a certain distance   of the part (21 a, 22 a) of the respective elements forming   guide faces, in a plane located in front of the front side eur of this part.   5 Device according to one of the claims   1 to 4, characterized in that the elements (21, 22)   forming guide surfaces and the element (20) forming   directing face for the ribbon are part of a dispostif   guide made in one piece and fixed to the imager pressure.