FR2916999A1 - CUTTING DEVICE FOR THERMAL PRINTING MECHANISM FOR SEPARATING A PRINTED COUPON FROM A STRIP FORMING A PRINTING MEDIUM - Google Patents

Abstract

The invention relates to a cutting device adapted to be implanted in a thermal printing mechanism for separating a printed coupon from a print-forming strip. This cutting device comprises a counter blade (6) which is fixedly mounted on a frame (1) of the mechanism, and a cutting tool (12) associating a blade (7) connected to a drive member (9) of the blade (7) which is mounted movable in translation on the frame (1). A drive member (10) with a rotating shaft (11) is connected to the drive member (9) via transmission means (16) adapted to convert the rotary motion of the drive shaft (11). in translational movement of the drive member (9). The drive member (9) is arranged in a nut which is engaged on the blade (7) and which cooperates with a screw (17) constituting the transmission means (16).

Description

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  The present invention is in the field of thermal printing mechanisms, and more particularly the cutting devices equipping these mechanisms. It relates to such a cutting device for separating a printed coupon from a web forming a printing medium, and a thermal printing mechanism equipped with this cutting device. Thermal printing mechanisms are commonly organized for the delivery of a printed coupon from a packaged roll. Such mechanisms include a carrier frame of tape drive means to a thermal print head which is provided with heating points. The tape scrolls against the thermal print head, and the heating spots are selectively activated to print the tape. After printing, a cutter is used to separate the printed coupon from the tape stock. The drive means of the web comprise a drive member, such as a stepping motor or the like, which rotates a drive roller. The strip is placed in interposition between the print head and the drive roller, which are held in resilient support towards each other by means of deformable members, springs or the like in particular. The drive roller is mounted on the chassis so that the environment of the print head can be released for replacement of the tape when the resist is exhausted. For this purpose, the drive roller is mounted on the frame by means of a retractable roller support, consisting for example of a hinged lid or a dedicated member removably mounted on the frame. Currently, the cutting device is motorized and is related to control means for spontaneously causing the separation of the coupon after printing. The cutting device more particularly comprises a cutting tool associating a blade carried by a blade support mounted to move in translation on the frame, and a counter blade fixedly mounted on the frame. The blade holder is driven by a driving member

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  dedicated, such as a DC motor or the like, being guided in translation on the chassis. The blade support is in relation with the motor member via transmission means interposed between them, which are organized to convert the rotating movement of the motor member into translational drive movement of the blade support. The movement of the blade is carried out in sliding superposition on the counter blade, the latter preferably being resiliently oscillating on the frame to promote the cooperation between the blade and the blade against. Currently, the cutting edge of the blade is arranged in one or more bevels which are inclined transversely to the direction of movement of the blade, to obtain a gradual cutting of the coupon promoting a smooth and even cutting line.

  There arises the problem of the general organization of the cutting device, and more particularly means for driving the blade in translation. It is desirable for the cutting device to be structurally simple and of limited size to avoid having to increase accordingly the size of the thermal printing mechanism which it is intended to equip, or even to allow its easy installation in any thermal printing mechanism. This restriction of space is all the more difficult to obtain as the blade is moved in translation, and that its stroke tends to increase the space required for the cutting device. Furthermore, the displacement of the blade must be regular and its implementation in cooperation with the counter blade must not induce undesirable tension on the coupon, to promote a frank, regular and progressive slicing of the strip. According to a known technique, the transmission means are of the eccentric or cam type, as described by US5749277 (WALKER) for example. The motor dedicated to driving the blade is engaged on a wheel train, which operates an eccentric cam in relation to the blade support, or the blade itself, for its drive in translation.

  This solution is not satisfactory because of the need to

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  limit the amplitude of the oscillating movement of the eccentric, to tend to make regular the translational movement of the blade support. The wheel train must be important to sufficiently limit said amplitude of movement, resulting in an increase in the size and complexity of the cutting device. Moreover, such an organization of the cutting device does not make it possible to obtain a satisfactory dynamic of the blade, and more particularly does not make it possible to obtain either a rigorous regularity of the displacement of the blade in translation, nor a comfortable amplitude of this displacement in translation because of the antagonistic search for having to limit the amplitude of the oscillating movement of the eccentric. According to another known technique, the driving of the blade in translation is of the rack and pinion type, as described by US5974930 (LONGROD) for example. The motor dedicated to the drive of the blade is engaged on a pinion, which is in connection with a rack formed through the blade support. This solution is not satisfactory because of the complex and bulky structure of the blade support, and its robustness necessary for its cooperation with the pinion. In addition, the axial orientation of the motor and the pinion, and their arrangement on the chassis induce a detrimental size of the device and difficulties for its implementation in the mechanism. The blade support is particularly bulky if not to limit the extension of the rack, and therefore to limit the amplitude of displacement in translation of the blade. Such a drive technique of the blade provides its regular displacement in translation, but requires a restriction of the amplitude of this displacement to the detriment of the quality of the cut obtained, including progressive slicing and frank band. To overcome the restriction of amplitude of the translational movement of the blade, it is common to incline the bevel it comprises as little as possible, to the detriment of the quality of the slicing obtained. Another known solution is to arrange the bevel in a pair of elementary bevels with opposite inclinations, and to practice

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  in their intersection zone a cut. If the inclination of the elementary bevels can be increased while limiting the amplitude of displacement in translation of the blade, the cut obtained is not clear and sharp, especially in the intersection zone of the elementary bevels. The object of the present invention is to provide a cutting device adapted to be implanted in a thermal printing mechanism, for separating a printed coupon from a printing medium strip. The present invention also relates to a thermal printing mechanism equipped with such a cutting device. It is more particularly the object of the present invention to propose such a cutting device which is of a simple structure making it possible to limit its bulk, as well as the number and the mass of the members used, without however affecting the robustness and the reliability of the device and while providing a frank, regular and progressive cutting of the band. The device of the present invention is a cutting device adapted to be implanted in a thermal printing mechanism for separating a printed coupon from a print medium strip. This cutting device comprises a blade against which is fixedly mounted on a frame of the mechanism, and a cutting tool associating a blade connected to a drive member of the blade which is mounted movably in translation on the frame. This cutting device also comprises means for guiding the blade in translation on the chassis and a drive member with rotating shaft in relation to the drive member via transmission means, which are able to convert the movement. turning of the motor shaft in translation movement of the drive member.

  The frame is an organ of the thermal printing mechanism which constitutes a support for receiving the functional and structural elements of this mechanism. This frame is likely to be composed of several bodies assembled together, such as a main body including housing a thermal print head and band drive means in elastic application against this thermal printing head. Such a main body further receives at least the blade and its drive means in translation in a frontal orientation to the general extension of the band. This translational movement is reciprocating between a resting position of the blade in which it is set back from the strip, and a working position in which it is brought in at least partial superimposition of the counter. blade to slice the band. The blade against is likely to be carried by the frame through the main body, but preferably via a drive roller support of the strip which is constitutive of the frame and which is mounted retractable on the main body, such as movably consisting of an articulated lid, or removably or the like, for obtaining a retraction of the drive roller allowing easy access to the print head for the purpose of replacing an exhausted tape roll. The cutting device is more particularly of the type in which the guide means of the blade, the axis of rotation of the rotating shaft, the transmission means, and the direction of displacement in translation of the blade, are oriented according to respective directions which are generally parallel and which are in correspondence with the slicing direction in front of the general extension of the strip. More particularly, the paralleling of the similar orientations of the axis of the rotating shaft and the transmission means, with those of the guide means and thus of the slicing direction, facilitates the implantation of the cutting device into the mechanism. thermal printing, avoiding an increase in its bulk in the direction of its thickness, and more particularly according to the thickness of the frame with respect to the direction of displacement in translation of the strip. From this choice of organization of the cutting device to exploit the advantages it provides, the inventive step of the present invention was in its entirety to minimize the volume occupied by the drive member of the blade in translation , to allow its grip on the latter following a restricted area

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  placed on the back of the blade, in its rear zone opposite to that of its cutting edge. These arrangements make it possible to optimize the amplitude of the displacement of the drive member and thus the travel traveled by the blade. Such a displacement amplitude of the blade provides a smooth and gradual slicing of the strip by means of a cutting edge whose bevel arrangement can be optimized without inducing an undesirable increase in the size of the cutting device. An ideal arrangement of the cutting edge lies in particular in a bevel with a single slope of significant inclination.

  The drive member is engaged at the edge of the rear zone of the blade, being advantageously reduced to a nut having a small contact surface with the blade for their engagement with each other, this nut moving along a screw driven by the drive member. The connection between the drive member and the blade can be easily obtained by means of space-saving and easy to implement, such as by interlocking, by embedding and / or by sealing, in particular by bonding, by welding, by overmoulding or similar technique. Such a connection is obtained with a small footprint and at lower cost, while providing an ideal accuracy of the relative positioning between the drive member and the blade. The screw can easily extend to the side of the motor member to occupy the same space defined between the front and rear walls of the frame with respect to the slicing direction. The limitation of this space is however not restrictive for a given size to the desired amplitude of the displacement of the drive member, and provides an optimized compactness of the frame and the cutting device in the slicing direction. This compactness is achieved in particular by avoiding cumulating the axial size of the drive member and the screw despite their similar orientation in the slicing direction. The connection between the screw and the rotating shaft of the drive member can be easily obtained from a wheel or a wheel train, interposed laterally between them in an available space of extension of the following frame the

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  direction of extension of the printing head of the mechanism and the drive roller of the belt. The length of the screw and its pitch are easily adjustable as needed, and more particularly according to the configuration of the thermal printing mechanism in which it is desired to implement the cutting device. The drive member being arranged in a nut in direct engagement with the screw, this adjustment is convenient. In addition, a matching of the bevel arrangement and the pitch of the screw is easily adaptable to provide a precision of the displacement of the drive member, and therefore a precision of the steady and adapted progression of the slicing of the band according to the characteristics of the bevel forming the cutting edge of the blade The reduction of the drive member to a nut is still a step to dissociate the drive modes of the blade modalities of its guide in translation. More particularly, the drive member and the guide means are structurally dissociated and are respectively and independently linked to the blade. The organization of the guide means is facilitated because of their structural isolation with respect to the junction between the blade and the drive member, and therefore the size of the guide means can be reduced and their structure specifically adapted and simplified. The connection between guide members and the blade can be easily obtained, the blade being connected to guide members cooperating with complementary guide members that includes the frame. Such a connection provides an ideal accuracy of the relative positions between the blade and the frame, and can be easily obtained by means of space-saving and easy to implement, such as from a shaping of the blade, or and preferably by interlocking, by embedding and / or by sealing, in particular by bonding, by welding, by overmolding or similar technique. In addition, the blade guide means, which are structurally simplified, can be easily completed to promote the implementation of

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  relationship between the blade and the counter blade. In particular, these guiding means may implement bearing rollers against the lateral edges of the blade operated for its translational guidance on the frame, these rollers being placed in the slicing zone to allow a recovery of the cutting forces and to guarantee an ideal relative positioning of the blade and against the blade, including in the case where the latter is mounted in an elastically floating manner or the like on the chassis. The rollers are essentially mounted on the chassis, being indifferently carried by the main body of the chassis or by the support of the drive roller. More particularly, the cutting device of the present invention is mainly recognizable in that the drive member is arranged in a nut which is engaged on the blade and which cooperates with a screw constituting the transmission means. According to an advantageous embodiment, the drive member and the guide means together form a blade support, being structurally dissociated and independently linked to the blade. These arrangements have the advantage of allowing a dissociation between the materials from which are respectively formed the blade, the nut, and guide members assigned to the blade and constituting guide means, sliders or the like in particular. These various materials are likely to be chosen from metallic or plastic materials of variable and suitable nature and density, which are capable of offering specific characteristics of resistance relative for example to expansion and / or friction, depending on the functions specifically sought for the organs they constitute respectively. In addition, the independence of the connection modalities between the blade and the nut and the guide means respectively, makes it possible to choose various suitable solutions for jointing or fitting the blade with the nut and the guide means respectively. The guide means of the blade comprise for example lateral slides or the like which is provided with the blade, which cooperate with respective or similar channels that includes the

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  frame. The slides and the corridors are complementary guide members constituting the guide means, the size of the sliders can be reduced to facilitate their connection with the blade and limit their size. The notions of sliders and corridors do not however prejudge in their generality of the conformation and the respective arrangement of the guide members in translation of the blade on the frame. In particular, the sliders are indifferently arranged in rail or slide, and cooperate by sliding interlocking with the corridors which are of complementary conformation. The sliders and the blade are connected to each other indifferently by interlocking, by embedding and / or by sealing or shaping the blade. The blade and the nut are connected to one another indifferently by interlocking, by embedding and / or by sealing. To provide appropriate guidance without affecting the drive of the blade, it is preferred to secure the blade with the sliders and arrange a set of positioning between the nut and the blade. However, it is conceivable by analogy to make the blade integral with the sliders and with the nut, and to provide a set of positioning between the frame and the sliders, a game that can be caught by elastic means interposed between them. Incidentally, rolling members may be interposed between the slides and the corridors. However, the proposed methods of organization of the guide means in sliders and corridors to simplify the guide means are sufficient in themselves to provide the precise and regular guidance sought, especially from their setting in association with the pressure rollers as referred to above.

  The blade is advantageously formed of a plate through which are formed by cutting a first median receiving housing of an interlocking lug, or even embedding, that includes the nut, and a pair of second side receiving housings interlocking pins and preferably recess, that comprise the sliders. The first housing and the

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  second housings are also capable of receiving respectively the pin and the pins by overmolding a plastic material. The guide means of the blade preferably comprise lateral extensions that includes the blade, which form guide plates flowing between guide members that includes the frame. These guide plates are formed in particular parallel to the slicing direction, and delimit between them a space in which extends the cutting edge of the blade. Such guide plates extend in particular along the lateral edges of the blade between its cutting edge and its back. The guide members advantageously combine rollers and a seat formed along the corridors, between which the guide plates circulate. The rollers are more particularly arranged in the slicing zone of the strip, being axially oriented transversely to the direction of movement of the blade. The rollers are rotatably supported by the frame, either by the frame body or by the drive roll holder. Ideally, the rollers are arranged slightly behind the edge of the counter-blade cooperating with the cutting edge, so that they exert a thrust on the blade, and more particularly on the guide plates, during the cooperation of the blade with the counter blade. Such thrust tends to cause an elastic tilting of the blade in its general plane and consequently to maintain the slides in cooperation with the corridors to strengthen the positioning of the blade during its movement along the frame. The cutting edge of the blade is preferably shaped as a monodirectional inclination bevel which extends between the guide plates. Such a bevel is likely to be provided with a toothing or microdenture without affecting the character of its general inclination advantageously monodirectional. The independent connection by interlocking or the like of the blade respectively with the nut and with the sliders makes it easy to obtain these connections by shaping the blade. More

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  particularly, the second housing is shaped in slits or the like which are formed through the plates. The first housing is formed of at least one indentation or the like formed through the blade at the edge of its back in the median axis of the bevel. By analogy, several notches can jointly constitute the first housing, being distributed on either side of the median axis of the blade to not affect the quality of its guidance and to avoid any risk of wagering at its displacement in translation. The first and second housings are likely to be easily made by stamping or similar technique. A cutting tool constituting a cutting device of the present invention will be recognized in that it consists of a blade shaped as a plate, this plate being provided with means of connection independently with the nut in its rear central zone. and with the slides in its lateral zones, rear in particular. The plate is capable of being secured to at least one of the sliders and / or the nut. According to a preferred embodiment, the plate is integral with the guide slides in its lateral zones, or even the nut in its central zone. The blade is a unitary piece at least with the sliders, or even with the nut, so that the cutting tool is capable of integrating, in one piece and from a simple structure, the blade and the means necessary for its guidance in translation on the chassis of a thermal printing mechanism, regardless of its connection with the drive member. The blade is directly engaged with the frame by means of the sliders, and indirectly engages the frame by means of the nut and transmission means. It follows that a positioning at several points of the blade on the frame is achieved. Such multipoint positioning can be easily compensated from a simplified structure of the cutting tool and / or its connection with the chassis, or from a fitted grip with a positioning set of the blade with at least one of the sliders and / or the nut,

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  from an adjusted grip with a set of positioning between the cutting tool and the frame, possibly compensated by elastic means of the type advantageously constituted by deformable members interposed between the cutting tool and the frame, or again to from a deformability of the nut and / or slides, for example obtained by their conformation and / or by means of an elasticity of their material. The screw is likely to be mounted coaxially with the rotating shaft. However, and to limit the size of the device in the direction of movement of the blade, the screw advantageously rubs the motor member extending parallel to the axis of extension of the rotating shaft. More particularly, the transmission means comprise at least one wheel for connecting the screw and the rotating shaft. The screw is radially offset from the rotating shaft and extends parallel to the axial extension of the motor member next to the latter. The notion of placing the screw and the motor unit side by side does not prejudge their respective axial extension dimensions, and corresponds to an arrangement of the screw and the motor member in the same space delimited between one face. front and a rear face of the frame or by analogy of a frame body which carries them together. The present invention also relates to a thermal printing mechanism incorporating a cutting device. This thermal printing mechanism is more particularly of the type in which the frame houses the drive member and the transmission means in at least parallel axial or coaxial axial directions corresponding to the orientation of the guide means in translation of the blade on the frame. According to the present invention, such a thermal printing mechanism is mainly recognizable in that it is equipped, and more particularly in that it incorporates, a cutting device as described above, to cut the web forming a printing medium for separating a printed coupon.

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  The present invention will be better understood on reading the description which will be made of an exemplary embodiment, in connection with the figures of the attached plates, in which: Fig.1 is an exploded perspective illustration of a mechanism thermal printing device incorporating a cutting device of the present invention. FIGS. 2 and 3 are partially assembled perspective illustrations of the thermal printing mechanism shown in FIG. 1. In the figures, a thermal printing mechanism comprises a frame 1 carrying a thermal printing head. 2 and a drive roll 3 of a printing tape in application against this thermal printing head 2. The frame 1 is essentially composed of a support 4 of the drive roller 3 which is removably mounted on a main body 5 of the frame 1, so that the driving roller 3 can be retracted to allow the replacement of a roll of exhausted tape. For clarity of the illustrations, the support 4 of the drive roller 3 is not visible in fig.2 and fig.3. The main body 5 carries at least part of the main functional components of the mechanism, such as the thermal printing head 2, not shown means for driving the roll 3, and a cutting device for separating a printed coupon from the remainder band. The cutting device comprises a counter blade 6 which is fixedly mounted on the support 4 of the drive roller 3, and which cooperates with a blade 7 mounted to move in translation on the chassis 1, and more particularly on the main body 5. The fixed mounting of the counter blade 6 is by analogy to take into account in view of a faculty offered to be able to oscillate in its general plan, to support the setting in cooperation between the blade 7 and the counter blade 6 during the operation of cutting of the band. This oscillation results from a mounting of the counter blade 6 on the support 4 of the driving roller 3 by means of elastic means 8 taking antagonistic supports against the support 4 of the driving roller 3 and against the counter blade 6 in his general plan.

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  The blade 7 is connected to a drive member 9 to cause it to move in translation, which is connected with a drive member 10 with a rotating shaft 11. The drive member 9 and the blade 7 are connected to each other. the other by flexible interlocking, or by embedding together to form a cutting tool 12 advantageously monobloc. Such connecting means between the blade 7 and the blade support 9 make it possible to simplify the structure and to reduce the size of the cutting device, while at the same time giving them adequate strength to make the accuracy of the translational movement of the blade 7 reliable. on the chassis 1. To bind the blade 7 to the drive member, the latter comprises a lug 13, preferably of polygonal section, which is received by interlocking inside a first housing 14 median that includes the blade 7 on the edge of its rear area. This lug 13 and the first housing 14 constitute connecting means between the nut 9 and the blade 7, this connection being capable of being a solid connection or a connection leaving a set of positioning between them. This rear zone corresponds to the back of the blade 7 opposite its cutting edge 15. The connection between the first housing 14 and the lug 13 is preferably made by interlocking fitted with a tolerance avoiding stressing between them when moving. of the blade 7 in translation. In the exemplary embodiment illustrated, the lug 13 is formed of a single relief cooperating with a first housing 14 formed in the median zone of the blade 7. The lug 13 is nevertheless capable of being composed by analogy of a plurality of elementary reliefs cooperating with corresponding first elementary housings. Transmission means 16 are interposed between the motor 10 and the drive member 9 to convert the rotary movement of the shaft 11 of the motor 10 into reciprocating translation movement, between a working position in which the blade 7 is placed in superposition of the counter blade 6 to slice the strip, and a rest position in which the blade 7 is removed towards the rear of the frame 1, and more particularly towards the rear of the main body 5.

  This rear zone of the chassis 1 corresponds to an opposite zone to

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  a front zone in which is installed against the blade 6. The translational movement of the blade 7 is made in a plane transverse to the general extension of the band. The drive member 9 is arranged in a nut and is engaged on a screw 17 driven in rotation by the motor 10. In the rest position, the nut 9 is placed at the end of the screw 17 which is located towards the rear area of the frame 1, and progresses along the screw 17 during the displacement of the blade 7 in translation between its working and rest positions. The axis of the motor 10 is oriented parallel to the direction of displacement in translation of the blade 7, and the screw 17 is engaged on the rotating shaft 11 by means of a wheel 18, so that the screw 17 is extended to the side of the engine 10 in the same space delimited between the front zone and the rear zone of the chassis 1. The respective extensions of the screw 17 and the motor 10 side by side make it possible to limit the bulk of the chassis 1, their ends rearward respectively being substantially located in the same plane orthogonal to the direction of displacement of the blade 7 in translation. The screw is carried at its rear end by the wheel 18 engaged on the rotating shaft 11 of the motor 10, and at its opposite end by the frame 1, and more particularly by the main body 5, which comprises a cradle 28 for his reception. Guiding means 19 laterally accompany the movement in translation of the blade 7 along the frame 1. These guide means 19 comprise lateral slides 20 which are connected to the blade 7, by interlocking but preferably by embedding. More particularly, the sliders 20 comprise nubs 21 nesting inside second housings 22 that includes the blade 7. These pins 21 and these second housing 22 constitute connecting means between the blade 7 and the guide means 19 , this link preferably being an integral connection but being capable of being a link which provides a positioning clearance between them. In the exemplary embodiment illustrated, these pins 21 are in torque for each of the sliders 20, and the second housing 22 consist of grooves which have an overall conformation H and whose legs are intended for the

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  respective reception of the pins 21. The number of pins 21 and corresponding second housing 22 indifferent since their cooperation gives the blade 7 a one-piece character together with the slides 20. These slides 20 are provided to cooperate with corridors of guidance 23 which comprises in correspondence the frame 1, and more particularly the main body 5. The guide means 19 of the blade 7 in translation also comprise side plates 24 that includes the blade 7. These guide plates 24 are intended to circulate between guiding members 25,26 that includes the frame 1, which combine a seat 26 formed along the guiding corridors 23 and 25 mounted rollers on the frame 1, and more particularly on the main body 5. The blade 7 is provided at at least one of its lateral edges with a guide ramp 27, which allows the blade 7 to take an elastic support against the blade 6 lor s from his passage to his work position. The guiding of the blade 7 by means of the rollers 25 allows a recovery of forces against the elastic means 8 used for the oscillating mounting of the counter blade 6 on the frame 1. Such a recovery of effort induces a pushing on the blade which tends to cause it to tilt in its general plane, with the advantage of reinforcing the cooperation between the sliders 20 and the guiding passages 23. The cutting edge 15 of the blade 7 is arranged in a bevel inclination monodirectional, which s extends between the guide plates 24. Such an arrangement is allowed while limiting the size of the cutting device, from the operation of the drive member 9 arranged in a nut, which is engaged on the edge of the the back of the blade 9 and which cooperates with the screw 17 which extends to the side of the motor member 10 along axes of parallel extension and corresponding to the general direction of displacement of the blade 7 in translation.

Claims (12)

  1. A cutting device adapted to be implanted in a thermal printing mechanism for separating a printed coupon from a printing medium band, this cutting device comprising a counter blade (6) which is fixedly mounted on a frame (1) of the mechanism, and a cutting tool (12) associating a blade (7) connected to a drive member (9) of the blade (7) which is mounted movable in translation on the frame (1), the device comprising means for guiding (19) the blade (7) in translation on the frame (1) and a drive member (10) with a rotating shaft (11) in relation to the driving member (9) by means of intermediate transmission means (16) adapted to convert the rotary movement of the drive shaft (11) into translational movement of the drive member (9), characterized in that the drive member (9) ) is arranged in a nut which is engaged on the blade (7) and which cooperates with a screw (17) constituting the transmission means (16).   2. Cutting device according to claim 1, characterized in that the drive member (9) and the guide means (19) jointly form a blade support being structurally dissociated and independently related to the blade (7) .   3. A cutting device according to claim 2, characterized in that the guide means (19) comprise lateral slides (20) which is provided with the blade (7), which cooperate with respective channels (23) that includes the frame (1).   4. Cutting device according to claim 3, characterized in that the sliders (20) and the blade (7) are connected to each other indifferently by interlocking, by embedding and / or by sealing, or by shaping of the blade (7).   5. Cutting device according to any one of the preceding claims, characterized in that the blade (7) and the nut (9) are connected to one another indifferently by interlocking, by embedding and / or by sealing . 18   6. Cutting device according to claims 4 and 5, characterized in that the blade (7) is formed of a plate through which are formed by cutting a first median housing (14) for receiving a pin (13). comprises the nut (9), and a pair of second lateral housing (22) receiving pins (21) that comprise the slides (20).   7. Cutting device according to any one of the preceding claims, characterized in that the guide means (19) comprise lateral extensions that includes the blade (7), which form guide plates (24) which circulate between guiding members (25,26) that includes the frame (1).   8. Cutting device according to claims 3 and 7, characterized in that the guide members combine rollers (25) and a seat (26) formed along the edges (23), between which the guide plates (24) circulate. ).   9. Cutting device according to any one of claims 7 and 8, characterized in that the cutting edge (15) of the blade (7) is in the form of a monodirectionally inclined bevel which extends between the guide plates (24) .   10. Cutting device according to any one of claims 3 to 9, characterized in that the cutting tool (12) consists of a plate (7) shaped as a plate provided with connecting means (13, 14, 21,22) independently with the nut (9) in its rear central zone and with the sliders (20) in its rear lateral zones.   11. Cutting device according to any one of the preceding claims, characterized in that the transmission means (16) comprise at least one wheel (18) for connecting the screw (17) and the rotating shaft (17). 11), the screw (17) being radially offset from the rotating shaft (II) and extending parallel to the axial extension of the motor member (10) adjacent thereto.   12. Thermal printing mechanism incorporating a cutting device according to any one of the preceding claims, wherein the frame (1) houses the drive member (10) and the transmission means (16) in parallel axial orientations. corresponding to the orientation of the guide means (19) in translation of the blade (7) on the frame (1).