EP1426316B1 - Device for feeding roll paper for printer - Google Patents

Abstract

The paper supply has a cradle (3) with lateral cheeks (4), a support (5) for rollers (7) that carry the outer periphery of the roll of paper (6), which is free to rotate on the rollers when the paper (10) leaving the roll is subject to traction (9). A brake (13,14) presses against the end face of the roll of paper reduce the effects of inertia of the roll.

Description

The present invention relates to improvements in the field of ribbon paper feed, in the form of a roll, to printing machines and, more particularly, to improvements in paper roll conveyors for a printer machine, comprising a cradle provided with lateral flanges, support means located at the lower part of the cradle and forming a cradle for supporting a paper roll so that said paper roll rests freely on said support means by its lower periphery and freely rotates on said support means when the free end of the paper ribbon is subjected to traction, this device further comprising braking means of said rotating roller which are integral with said cradle and which have at least one elastic support member against the one side of the paper roll.

The paper feeding devices of the kind considered are appreciated by the users because of the simplicity of setting up a roll of paper: there is no organ to actuate or move, there is no axis to introduce into bearings, the paper roll is simply deposited on its support at the bottom of the cradle (which generally comprises two idle rollers on which the roller turns freely).

However, in some applications, paper rolls of large capacity are used which have a relatively large diameter (for example typically of the order of 20 cm) and which are heavy (for example typically of the order of 2 kg). As a result, A new or substantially complete roll has a substantial inertia when it is rotated by the printer during operation. However, this roller, resting freely on idle rollers of the cradle, continues to unfold when the printer machine stops working and the peripheral turns of the roller are released (decompartmentalization). This results in the risk of inadvertent unwinding of the paper, a tangling of the paper, tearing of the paper, or even a blockage of the feed device.

The document US 2,899,145 discloses a roll paper feed device which has rotating roller braking means which are arranged to act on the sidewalls of the roll. However, this known device is designed for printing paper rolls which are very bulky and therefore very heavy (several tons). As a result, the braking means are arranged accordingly and are complex. Such means are not suitable for a printer machine paper feed device, which device must remain as compact and as simple as possible.

The object of the invention is to provide improved means for providing reliable operation of the feeding device operated in conjunction with a printer machine in order to avoid the disadvantages presented by the current devices, the improvements thus brought before, in the whole of the machine. wherever possible, be structurally simple and inexpensive while being effective.

For these purposes, the invention proposes a roller paper feed device for a printer machine as mentioned in the preamble which is characterized, being arranged in accordance with the invention, in that said elastic support member comprises at least one resiliently deformable arm integral with the cradle and at least one projecting zone which is located at the free end of said arm and which is engaged through a opening in a side flange of the cradle and projecting from the inner face of said flange, and in that said projecting zone is in the form of protruding pellet which comprises a substantially flat bearing surface clean to bear against a side of the roller and circumferentially surrounded by an inclined surface adapted to slide on the sides of the roll when it is introduced into the cradle.

Thanks to the provisions of the invention, one achieves in a simple and effective way to the desired goal, that is to say that the roll of paper, rotated by a traction exerted on its free end, is constantly braked so that when the traction force is interrupted, the roller can no longer continue to turn on the road because of its inertia and stops instantly: it avoids the breakdown of the last turns of the paper that could be seen in the previous devices. The means used for braking the roller are simple and require no adjustment. In addition, as it is desirable, the braking force is not excessive so as not to require too much traction force from the drive means of the associated printer machine.

In an advantageous exemplary embodiment, said inclined face may be of substantially frustoconical shape. Or, when said support pad is slightly protruding from the flange of the cradle, it can provide that said inclined surface is rounded with a substantially quadrant cross section.

To avoid too fast damage of the braking members in contact with the cutting edges of paper turns, at least the bearing face of each projecting zone is metallic, in particular made of steel.

In a simple manner, said support surface may be round.

Preferably, the elastic bearing member of the braking means bears against the side of the roll in the lower part thereof.

In a particularly interesting way, it is also possible for the braking means to comprise a second support member situated on the other side of the roller and provided with a second substantially identical projecting zone which is arranged facing the aforementioned first projecting zone. , to be in support against the other side of the roll. In a preferred embodiment, the second protruding zone may be fixed and integral with a flange of the cradle. But alternatively, it may be interesting that the second protruding zone is located at a free end of a second integral elastic arm, at its opposite end, the other flange of the cradle.

The provisions that have just been stated find a particularly interesting application when the cradle is equipped with two idle rollers for supporting the roll of paper.

• la figure 1 est une vue schématique de côté, en coupe partielle, d'un dispositif d'alimentation en papier en rouleau agencé conformément à l'invention ;
• la figure 2 est une vue en coupe, selon la ligne II-II de la figure 1, du dispositif de la figure 1 ;
• la figure 3 est une vue en coupe, analogue à celle de la figure 2, d'une variante de réalisation du dispositif de la figure 1 ;
• la figure 4 est une vue en perspective d'une partie constituante du dispositif des figures 1 à 3 ; et
• la figure 5 est une vue en coupe transversale d'une variante de réalisation de la partie constituante de la figure 4.

The invention will be better understood on reading the following detailed description of certain preferred embodiments given solely by way of non-limiting examples. In this description, reference is made to the accompanying drawings in which:

• the figure 1 is a schematic side view, in partial section, of a roll paper feeder arranged in accordance with the invention;
• the figure 2 is a sectional view, along line II-II of the figure 1 , of the device of the figure 1 ;
• the figure 3 is a sectional view similar to that of the figure 2 , an alternative embodiment of the device of the figure 1 ;
• the figure 4 is a perspective view of a constituent part of the device of Figures 1 to 3 ; and
• the figure 5 is a cross-sectional view of an alternative embodiment of the constituent part of the figure 4 .

Referring first to the figure 1 , a roll paper feeding device 1 is functionally associated with a printer machine 2.

The feed device 1 comprises a cradle 3 provided with lateral flanges 4 (the front flange, on the figure 1 , was torn off so that the inside is visible). The bottom 5 of the cradle 3 is arranged in the form of a support or incorporates support means for a roll of paper 6. In the usual arrangement illustrated in FIG. figure 1 at the bottom 5 are associated two idlers 7 which are rotated on respective transverse axes (parallel to that of the roll 6), spaced apart from each other and projecting above the bottom 5, so that the roll 6 is simply placed on the rollers 7 and can freely rotate (arrow 8) when the printer machine 2, in operation, exerts a pull (arrow 9) on the paper tape 10.

The cradle 3 is, in general, integrated in a housing closed by a cover (not shown).

When the roll of paper 6 has a large mass (for example typically roll 20 cm in diameter, having a weight of the order of 2 kg), it continues to unfold, because of its inertia, when the effort of pulling ceases to exert on the ribbon 9 and this results in a loosening of the first turns of the roller (désoisonment).

To avoid this disadvantage, the roller 6 is associated with braking means 13, supported by the cradle 3, which have at least one member 14 resiliently against at least one side of the roll 6.

Both to simplify the structure and so that the braking means 13 are active regardless of the effective diameter of the roller 6, it is expected that the elastic bearing member 14 against the side of the roller is located opposite the part bottom of it, as shown in figure 1 .

A simple arrangement consists in that the resilient support member 14 is arranged at the lower part of the bottom 5, between the two rollers 7.

The elastic support member 14 exerts on the side of the roll a transverse force (arrow 15 on the figure 2 ) sufficient to brake the roller when the tensile force 9 is interrupted and prevent the last striations of the roll 6 from being deformed, but however small enough not to disturb the correct rotation of the roll and the correct drive of the paper ribbon under the action of training means (in the printer machine) which must not be modified.

The elastic support force (shown schematically by the arrows 15 on the figure 2 ) may result from the constitution of the support member 14 or be conferred by a spring.

As illustrated in figure 1 , the resilient support member 14 comprises a raised area or protruding area 16 engaged through an opening 17 formed in one of the side flanges 4 of the cradle 3 and projecting from the inner face of said flange.

As illustrated in figure 2 this raised area 16 is in the form of a projecting pellet having a substantially flat bearing surface 18 adapted to bear against a side of the roll 6.

In a simple manner, the protruding zone 16 can be located at one end of a deformable arm 19 secured at its other end to the cradle 3.

To ensure that the rotation of the roller is not impeded by the braking means, it is preferable that two protruding bearing regions are respectively applied to the two sides of the roll 6, preferably symmetrically (ie say that the two protruding areas are arranged approximately facing each other on both sides of the roll).

In a preferred embodiment illustrated in figure 2 , the arrangement described above is doubled by providing, on the other side of the cradle, a second protruding support zone 16, in particular also in the form of a projecting pellet, which is engaged through an opening 17 provided in the another flange 4 of the cradle 3 and which is supported by a second deformable arm 19.

In this case it is interesting that the two arms 19 are joined to each other by a transverse bar 20, so as to constitute a single piece in the form of clip which is snapped onto the cradle 3. Such a single piece is easy to manufacture for example by stamping if it is entirely metallic or by molding if it is plastic. Moreover its assembly is simple and fast.

We can also use the assembly of the figure 3 , in which one of the projecting zones, 16 ', which may also be advantageously in the form of a pellet, is fixed and integral with the flange 4 of the cradle 3, for example being integrally formed with said flange 4 as visible to the figure 3 (For example came die stamping on the cradle is metal or come molding if the cradle is plastic).

Only one of the projecting zones 16 is then movable transversely to the flange 4. This pellet 16 can be arranged as indicated above, being located at one end of a deformable arm integral with the cradle.

It is also possible, as an alternative, to provide that the protruding zone 16 has at its base a retaining collar 21, as illustrated in FIG. figure 3 , and that it is held in position only by a spring 22 bearing against an outer casing 23. It is then the assembly projecting zone 16-spring 22 which constitutes the support member 14.

To facilitate the positioning of the roller 6, each protruding support zone 16, 16 'is arranged in the form of a protruding pellet which comprises a substantially flat bearing surface 18, advantageously of round shape, which is surrounded peripherally by a sloped clean surface to slide on the edge of the roll when it is introduced.

An interesting arrangement is that said inclined surface is substantially frustoconical as visible on figures 2 and 3 and as illustrated in 24 on a larger scale and in perspective at the figure 4 .

However, when the projection of the pellet is relatively small on the inner face of the flange 4 (small clearance between the sidewall of the roll 6 and the flange 4), it is possible, as illustrated in section at the figure 4 , provide that the aforesaid inclined surface is constituted by a 25 quarter-rounded surface.

The side of the paper roll 6, formed by the edge of the winding turns of the paper, is particularly aggressive. It is therefore preferable that the bearing surface 18 of each projecting zone 16 is made of a very strong mechanical material, preferably of metal, especially steel. In the case where the protruding zone 16 is carried by a deformable arm 19, it is the assembly which can be metallic (or even the whole of the single piece forming a clamp), or the projecting zone 16 is secured to a metal arm 19 of another material, in particular plastic.

It will be noted that, whatever the embodiment envisaged, each projecting area 16 is fixed in the direction of rotation of the roll; on the other hand, it can accompany transverse movements of small amplitude of the roll (movement along the axis of the roll). In particular, in the case of the single clip piece illustrated in FIG. figure 2 this piece can be secured to the cradle 3 so as to be able to move transversely weakly relative thereto.

Note also that when the braking means comprise two support members located on either side of the roller as indicated above, these support members contribute to maintain the roller in a substantially constant axial position. The means of braking so arranged combine the two braking and guiding functions, without the need to resort to other means for guiding.

Claims (10)

1. Roll paper feed device (1) for a printing machine (2), comprising a cradle (3) provided with side cheeks (4), supporting means (5, 7) situated at the lower part of the cradle and forming a cradle for supporting a paper roll (6) such that said paper roll rests freely on said supporting means by its lower periphery and rotates (8) freely on said supporting means whenever the free end of the paper web (10) is subjected to a traction (9), this device additionally comprising braking means (13) for said roll (6) when being in rotation which are joined to said cradle (3) and have at least one member (14) for an elastic bearing against at least one side of the paper roll (6), characterized
   in that said elastic bearing member (14) comprises at least one elastically deformable arm (19) joined to the cradle and at least one protruding zone (16) which is situated at the free end of said arm (19) and which is engaged through an opening (17) provided in a side flange (4) of the cradle (3) and protrudes relative to the inner face of said flange (4), and
   in that said protruding zone (16) is shaped as a protruding stub which comprises a substantially flat bearing surface (18) adapted for bearing against a side of the roll and peripherally surrounded by an inclined surface (24, 25) adapted for sliding over the sides of the roll when this is introduced in the cradle.
2. Paper feed device according to Claim 1, characterized in that said inclined surface (24) is substantially truncated in form.
3. Paper feed device according to Claim 1, characterized in that the bearing stub is slightly protruding relative to the flange (4) of the cradle and in that said inclined surface (25) is rounded, with a substantially quadrant-shaped cross section.
4. Paper feed device according to any one of Claims 1 to 3, characterized in that said bearing surface (18) is round in shape.
5. Paper feed device according to any one of Claims 1 to 4, characterized in that at least the bearing face (18) of the protruding zone (16) is made of metal.
6. Paper feed device according to any one of Claims 1 to 5, characterized in that the elastic bearing member (14) of the braking means bears against the side of the roll (6) in the lower part of the latter.
7. Paper feed device according to any one of Claims 1 to 6, characterized in that the braking means (13) comprise a second bearing member situated on the other side of the roll and provided with a second, substantially identical protruding zone (16'), which is disposed facing said first protruding zone (16), so as to bear against the other side of the roll.
8. Paper feed device according to Claim 7, characterized in that the second protruding zone (16') is stationary and joined to the other flange (4) of the cradle (3).
9. Paper feed device according to Claim 7, characterized in that the second protruding zone (16') is situated at a free end of a second elastic arm (19) which is joined, by an opposite end thereof, to said other flange (4) of the cradle (3).
10. Paper feed device according to any one of Claims 1 to 9, characterized in that the supporting means for the paper roll (6) comprise two parallel and mutually spaced rollers (7).

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