FR2620371A1 - GRINDING BLADE CUTTING DEVICE, IN PARTICULAR FOR WRITING RIBBONS - Google Patents

Abstract

a) Cutting device with a grinding blade, in particular for writing ribbons. b) Device characterized in that the back pressure rings 5 also separated from each other by spacer rings 9 rest together with the spacer rings 9 on a retaining shaft 7 and each back pressure ring 5 being mounted on the retaining shaft 7 on a resilient seat with spring action in the radial direction. c) The invention relates to a cutting device with a grinding blade, in particular for writing ribbons.

Description

"Cutting device with grinding blade, especially for ribbons

  The invention relates to a grinding blade cutting device for cutting sheets, papers, thin fabrics or the like, with a driven blade shaft, on which mutually separated grinding blade rings are arranged. axially by means of spacer rings, against the blades of which

  are elastically squeezed rings of

  movable relative to each other,

  with the interposition of the substrate to be cut.

  Such cutting devices with a grinding blade are known for cutting in particular very thin leaves, such as leaves.

  labels, thin papers, but all

  in the production of writing ribbons for cutting fabrics from writing ribbons. The grinding blades are pressed under high pressure against a corresponding metal shaft of hard surface and the

  tissue lying between them is crushed accordingly.

  On this occasion, very strong requirements are

  the quality of the blades and the quality of the

  counter-shaft face, the surface of the latter to at least be lapped. The kinds of fabrics coming in

  question for writing ribbons are in particular

  bind cotton, natural silk and leaves in

  very thin thermoplastic bands.

  The grinding blades are mounted in the form of rings on a bearing tube acting as a blade shaft, which is provided with an inner heater for cutting such writing ribbons, heating around which

  turn the tube. Heating is done on this occa-

  radiated heat, in order to obtain a temperature

  as regular as possible over the entire surface

of the blade shaft.

  The grinding blade rings are adjusted by axially interposed spacer rings, so that the distance between the rotating blades of the grinding blade rings corresponds. precisely to the desired bandwidth. The attachment of the grinding blade rings and spacer rings is effected on the blade shaft by the fact that they are all rigidly tightened, for example between two corresponding fasteners or from one side, against a recess of corresponding shaft, so that the drive movement of the shaft can be transmitted to the grinding blades, by means of the link

  by friction obtained on this occasion.

  To apply the grinding blades to the blade shaft, it is necessary to

  sufficient tolerance to obtain a good application

  This tolerance is, for example, in the range of 0.1 mmn (for a shaft diameter of about 100 mm) without hindrance. This tolerance in the opening diameter of the grinding blade to be applied, however, causes a corresponding radial mutual offset of the individual blade cutting edges to occur, to which it is necessary to add the retouching correction tolerances, respectively of the first grinding of the blades. grinding blade rings (which are again in the same order of magnitude). This can lead to between two blades

  one side of the other, it appears that

  raises a maximum mutual offset of 0.2 to 0.3 mm even with tight tolerances. In any case, this tolerance is found to be too great, for example for writing ribbon fabrics which on their side only have thicknesses ranging from

  0,06 to 0,13 mm, so that when such tolerances

  appear, these fabrics could slip

without being cut out.

  In the case of cutting devices with

  grinding blade known in order to compensate for

  To each grinding blade, a corresponding pressure ring prestressed in the direction of the grinding blade is assigned to a clean prestressing device. This, however, led to

  for each grinding blade, a roll of

  clean impression was necessary, with a provision

  own preload (for example an arrangement

  pre-stressed piston-cylinder), which is very

  expensive and can only be adjusted and manipulated

  LEMENT. The plurality of such self-drive counterpressure rollers also led to the relatively lower lower limit of the width of the tape that could be cut, and even when using a mechanism

  bulky counter-pressure

  The width of the ribbons less than 8 mm was not possible. For such machines, there is also another problem, in that when applying a prestress to the fabric

  in order to obtain clean, transverse cutting edges

  salty to the direction of prestress (between the blades) the fabric bombs, this effect being felt more strongly with an increase in the mutual spacing of the grinding blades (so with a width of

growing ribbon).

  As a means of pressure, in another

  Known mill cutter, it uses no back pressure roll applied against a clean prestressing mechanism, but freely rotating counter pressure rings, movable between them and yet located next to each other rings which are elastically pressed together by a metal roller, and a soft rubber roller,

  against sharp edges of grinding blades. This solution

  Known first has the disadvantage that when stopping the leaf shaft the rings fall for lack of maintenance. Because in this known arrangement ring-to-ring, this leads to the point where the counter pressure rings next to each other press on the soft rubber roller, because of the smooth surface of the rings, also to for example, there are problems with the points of support of the rings located next to one another, because of the incompressibility of the rubber, the volumes of rubber are displaced because a ring is more strongly apart from the fact that precisely for very elastic rubbers

  ("soft"), there are significant losses by hysteria-

  sis (crushing work), losses which lead quickly to a heating of the rubber and in this occasion not only to a relatively high wear, but also to the risk that local cracks in the rubber occur. This is further favored by the

  only when printing a counter ring

  pressure more widely spread in the roller of con-

  soft pressure, noticeable local pressure spikes occur in the rubber roll,

  on its frontal edges, which can lead to

  local surge and destruction of rubber. In total, this cutting device with a grinding blade is

  nor is it appropriate to be the seat of tolerance

  these important or to compensate them. On the basis of this, the object of the invention is to improve a cutting blade device of the type indicated at the beginning, so that in the case of a simplified assembly and a smaller footprint, no additional support is required. necessary for other shafts or rollers, which allows for the seat of even larger tolerances and

  gives a better overall ability to operate

  is lying. According to the invention this is obtained for a grinder blade cutting device of the type indicated at the beginning, by the fact that the counter-pressure rings

  are mutually separated by rings of

  that they rest together on a tree of

  and that each counter-pressure ring is mounted on a resilient seat with a spring effect in the

  radial. Elastic rings preferably having

  this a circular section are used for resilient seats spring effect, silicone rubber rings are particularly suitable. In the device according to the invention, since the counterpressure rings are

  their side on a holding device, with interpo-

  of an elastic protective device, it is

  on the one hand to avoid completely the devices

  additional exteriors and thus obtain a

  Noticeably easier for a smaller footprint. Because of the support on a clean holding shaft, it is furthermore obtained that all the rings of

  counterpressure shall be maintained in common by that

  eg, removed together with the holding shaft, and can be quickly replaced by new counter pressure rings on another holding shaft. The desired initial pressure force can be applied simply by

  a corresponding preload of the main shaft

  in the direction of the grinding blades, each counter-pressure ring being able to perform automatically correctly and without influence on the part of the ring

  neighbor (as a result of the interposition of rings of

  the desired tolerance compensation, with the elastic device acting from the top, relative to the cutting edge of the grinding blade which is assigned to it. If, for elastic rings already

  evoked, we use for each ring of counterfeit

  spring resilient seat each year.

  However, the counterpressure water has a clean, radially effective elastic

  operated by the latter, because the rings of

  existing between two elastic rings of this kind do not require this elastic fixation and can therefore be directly applied to the holding shaft, however, that the rings

  spring elasticity of the grinding rings indi-

  viduals are separated from each other. We can not arrive in any way with effects

  unwanted alternatives between elastic devices

  This is for example the case of the already known pressure device with a soft rubber roller. The existing danger of cracking the rubber surface and thereby undesirable damage to it does not exist in the invention, since the rings may

  be made in the interstice between the diameter

  inside the counter-pressure ring and the dia-

  outside meter of the counter-pressure ring of

  retaining rings, in a suitable form, with an approximately round or at least radially outwardly curved section, so that there is no pressure of the lateral annular ridges in the ring, and enough space remains for deformed rubber volumes when

the deformation.

  Another embodiment, also preferred, of the shredder blade cutting device according to

  the invention consists in that springs, preferably

  The coil springs, which are held in radially developing bores in the holding shaft, serve as resilient seats with a spring effect radially. In order to achieve effects of

  compression as regular as possible on the whole

  ble of the periphery of the counterpressure disc, it is naturally constrained to provide as much as possible of these springs, radially between them, in

  preferably using no fewer than eight

  licoidal, arranged in a staggered manner regularly

on the periphery of the tree.

  Another preferred embodiment of the invention

  It also consists in that the holding shaft is coated with a continuous elastic coating to form the radially resilient spring seats for the counter-pressure rings and that on their inner radial surfaces the rings

  counterpressures are made with a section

  gap to the elastic coating. We obtain from

  makes a particularly fast editing, being

  For this embodiment, it is assured that undesirable reciprocal influence of the elastic backpressure conditions in the rubber will not occur for rings next to each other.

  other. On the one hand, the points on which

  the neighboring rings on the elastic layer

  killed on the holding shaft are clearly spaced from each other axially, because according to

  distance discs are interposed between

  be the rings of counterpressure. Moreover, the

  tion of the radial inner surfaces, in a form whose section is curved towards the elastic coating of the holding shaft, ensures that there is also no danger of surface cracking.

  rubber when pressed using a

  annular surface, as can happen however for the known device, having a roll of

  rubber pressure located externally.

  In a preferred manner, the elastic coating

  tick consists of a vulcanized silicone rubber

of sufficient thickness.

  In another preferred embodiment of the invention,

  vention it is expected that next to this tree, the tree

  retaining rings are also

trained.

  The cutting device according to the invention

  makes it possible to reach cutting widths

  killed below 4.2 mm, without necessarily being particularly expensive. With the

  cutting device according to the invention, it is possible

  both get very clean cutting edges and the overall assembly of the counterpressure shaft with the counter-pressure rings is extraordinarily simple; the rings can, if desired, be changed quickly, rings can be used

  trade flows at a very favorable price (

  key values of a few cents) for elastic spring-acting devices acting radially and adjustment and equipment, setting up at the beginning of the cutting process is also very simple; simply remove the preload of the holding shaft from the blade shaft until the last blade cuts. Tolerance compensation on the entire blade shaft is then performed on all the blades automatically and without problems. An example of the invention is shown in the accompanying drawings in which:

  FIG. 1 is a view of principle,

  respectively a partially cut representation of a cutting device according to the invention;

  FIG. 2 is a representation of

  principle tail (cutting direction: perpendicular to the longitudinal axis of the holding shaft) for two embodiments of another elastic assembly of the counter-pressure rings, and - Figure 3 is a representation of a principle of another embodiment for the

  elastic mounting of the counter pressure rings

  detail presentation, cutting direction in the longitudinal direction of the longitudinal axis of the holding shaft). FIG. 1 represents a representation of the principle (partially cut in the right half of the figure, if not seen from above) of a blade shaft 1 made in the form of a support tube, on which a plurality of rings of grinding blades 2 by interposing spacing rings 3. The grinding blade rings 2 have a peripheral cutting edge 4. By the choice of spacing rings 3 of appropriate width, the cutting edges 4 are each placed with a certain spacing with respect to two rings of grinding blades 2 situated one beside the other, spacing which corresponds exactly to the width of the substrate to be cut, for example a fabric of

writing ribbon.

  The blade shaft 1 is connected to a not shown drive device, by means of which it can be moved in rotation. The grinding blade rings 2 and the spacer rings 3 are mounted on the blade shaft 1 with a very narrow fit, but still sufficient to allow mounting

  unimpeded, a tree with blades

  shaft 10 at its right end of Figure 1, against which are tightened the blade rings of

  grinding 2 and the spacer rings 3, since the

  end of the blade shaft 1, so that the rotation of the blade shaft 1 can be transmitted to the rings of grinding blades 2 by a friction connection.

  The counterpressure exercised against

  chants 4 grinding blade rings 2 is produced

  by a counterpressure shaft, which consists of a holding shaft 7 (usually not driven), on which are mounted counter pressure rings 5

  function of the position of the grinding blade rings

  ge 2, also by interposing spacing rings

  9. Each counter-pressure ring 5 is arranged so that it can be pressed with its median zone against the blade edge 4 of the ring of

  grinding blade 2 assigned to it.

  The grinding blade rings 5 have an inside diameter which is greater than the outside diameter of the holding shaft 7 and they are mounted on the holding shaft 7 by rings.

  of silicone rubber 9 of circular section, ad-

  joints in the intermediate space between their inside diameter and the holding shaft 7. In the embodiment shown, the counter-pressure rings 5, as for the leaf shaft 1, are also fixed to prevent lateral sliding. ,

  on one side by a shaft recess 13 and on the

  axial end of the counterpressure shaft, by a stop element (not shown in FIG. 1) of position fixed for example by means of clamping by

  radially oriented screw, applied cor-

  on it, not giving rise here in any case

  no axial deformation of the rings of

  5 and spacer rings 9, since the counter-pressure rings can compress and

  extend during the operation of the device, inde-

  apart from the spacer rings 9 separating them, and

must be able to turn.

  When working, first remove

  the holding shaft 7 with the rings 5 and 9 by means of

  1, in order to be able to introduce the tissue to be cut between the cutting edges 4 of the grinding blade rings 2 and the surface of the counter-pressure rings. Immediately after the blade shaft 1 is moved in rotation and simultaneously the shaft of

  hold 7 is slowly started, facing the tree at-

  1. First, one or more ridge (s)

  pe is / are put in support against the rings of con-

  5 and the first cuts are produced, while due to tolerances, a few cutting edges 4 still located behind belonging to other grinding blade rings 2 still do not cut. Immediately thereafter, the pressure on the blade shaft 7 of the counterpressure shaft (acting in the direction of the arrows shown in FIG. 1) is slowly increased, causing

  that a solicitation of pressure

  of the counter pressure rings 5 already in con-

2620371I

  pressure tact with the cutting edges that are assigned to them, pressure urging which leads to that the counter pressure rings 5 are "crushed" elastically in the approximate direction of the holding shaft 7, starting from the fulcrum

  with the cutting edge 4, with elastic deformation

  that corresponding silicone rings that support them. The pressure on the holding shaft 7, in

  the pressing direction against the blade shaft i is ac-

  until the cutting edge 4 of the last year

  shred blade blade 2 also makes a cut

  after which the operation of the

  whole diet can be carried out while keeping this

ge.

  Because each counter-pressure ring is supported with respect to the holding shaft 7 by a rubber ring 8 which can deform elastically and a spacer ring

  is each time arranged between two rings of

  pressure 5, the spacer ring does not admit

  unwanted alternating solicitation when crushing

  Against the counterpressure ring 5 towards the neighboring counterpressure ring, it can be seen that, during the operation of the device, a recess and an extension of the counter-pressure rings, adapted to the special conditions of tolerances and pressure of each pair constituted of a counterpressure ring

  and a grinding ring, which is completely inde-

  during, so that is constantly guaranteed a

  operation on and compliant of the device.

  FIG. 2 shows another possibility of mounting an elastic device for

  elastically press the rings of

  5 against the holding shaft 7, two

  different possibilities being on this occasion

  felt for elastic support, in the upper half

  upper and lower half of Figure 2.

  In the case of the embodiment which is shown in the upper half of FIG. 2 radial bores are attached in the holding shaft 7, each of which receives the lower part of a coil spring 11, which bears with its part emerging on the surface of the holding shaft 7

  against the inner surface of the counter ring

  corresponding pressure, with some

chosen train of choice.

  In the case of the embodiment which is shown in the lower half of FIG. 2, the counterpressure ring 5 is elastically supported on the holding shaft 7, by means of projections 16 made on the inner surface, in

  section in the shape of an arc of a circle, made of an elastic material

  tick, vulcanized, for example into a rubber on the

appropriate licone.

  The representation of FIG. 3 finally represents yet another embodiment of the elastic support of the counter-pressure rings 5, in which the surface of the holding shaft 7 is

  provided with a coating 12 of an elastic material

  Deformable deformation of sufficient thickness. The counterpressure rings 5 are here provided with a realized form

  bent in section on their inner surface.

  radial direction, in the direction of the coating 12, making it possible to obtain a bulging support on the elastic layer 12, which provides

  especially favorable, the rubber

  formed having sufficient room laterally to deviate into the gap and which does not present any kind of danger of penetration of a sharpened edge

in the rubber.

Claims (3)

1 ') grinding blade cutting device for cutting sheets, papers, thin fabrics or the like, with a driven blade shaft, on which are arranged rings of grinding blades, mutually axially separated by means of bushings; spacing, against the blades of which are pressed resiliently against pressure rings, movable relative to each other, arranged with interposition of the substrate to be cut, characterized in that the counterpressure rings (5) also separated from each other by spacing rings (9) rest together with the spacer rings (9) on a holding shaft (7) and each compression ring (5) being mounted on the holding shaft (7) on an elastic seat with spring effect in radial direction.   2) Cutting device according to the claim   1, characterized in that elastic rings (8) preferably having a circular section are used for the seats Spring elastics.   3 &) Cutting device according to the claim   2, characterized in that the rings (8) elastically   spring-effect are rubber rings silicone.   4 ') Cutting device according to the claim   1, characterized in that springs (11), preferably coil springs, held in radially developing bores in the holding shaft (7) serve as elastically resilient seats. spring radially.   Cutting device according to claim 4, characterized in that at least eight helical springs (11) arranged in a manner   regularly and mutually displaced on the periphery from the tree.   6 ') Cutting device according to the claim   characterized in that the holding shaft (7) is coated with a continuous elastic coating (12) for producing the radially resilient spring seats for the counter-pressure rings (9) and on their surfaces ( 14), the counterpressure rings (9) are made with a   section curved towards the coating (12) elastic.   7) Cutting device according to the claim   6, characterized in that the elastic coating (12) consists of vulcanized silicone rubber, of sufficient thickness.   8) Cutting device according to any one   than claims 1 to 7, characterized in that   the retaining ring of the counter-pressure rings (8) is also trained.