WO2005090027A1

WO2005090027A1 - Constructive arrangements on sectioning mechanisms

Info

Publication number: WO2005090027A1
Application number: PCT/IB2005/050929
Authority: WO
Inventors: Ricardo Trauer
Original assignee: Bematech Indústria E Comércio De Equipamentos Eletrônicos Sa
Priority date: 2004-03-17
Filing date: 2005-03-16
Publication date: 2005-09-29
Also published as: BRPI0400434A

Abstract

The present invention relates to sectioning mechanisms that provide a cut with relevant technical innovation through 'double V' blades. One blade (1) has vertex (6) with an angle (r) on the cutter edge and distance (v) relative to the projections of the cutter edges. In addition, the other blade (2) has vertex (4) with an angle (a), larger than angle (r), on the cutter edge and distance (u) relative to the projections of the cutter edges. Additionally, there is relative inclination (b) between the two faces of the said blades, besides the driving devices enhanced on a compact way. Therefore, they provide an operational application on automated sectioning devices, such as printers or equivalent devices, with a greater efficiency and savings, on both the product and the manufacturing process.

Description

Description CONSTRUCTIVE ARRANGEMENTS ON SECTIONING MECHANISMS Technical Field

[1] The present invention relates to constructive arrangements on sectioning mechanisms whose inventive concept provides a cutting effect of laminar elements such as paper sheets, with a relevant technical innovation. This effect is caused by the interrelationship of a new arrangement and geometry of the cutting members; associated with the nature of the mechanical movement of these members, as well as with the cut operating mechanism and the structural means used on the corresponding mechanism. Therefore, the combination of these elements provides an operating application on automated cutting apparatuses, particularly printers or the equivalent, with efficiency and savings, both on the product and the manufacturing process. Background Art

[2] The sectionining mechanisms used on printers or the equivalent - such as facsimiles - to make the paper shearing, generally supplied by continuous rolls, make it possible the use of paper on sections or pages according to the application and the user's convenience. In order to make such shearing, in this way, the state of the art provides a number of sectioning mechanisms, which consist of two blades intersecting the paper on opposite sides.

[3] For example, US Patent No. 5090285 (KONDO) describes a mechanism that aims at the sheet cutting stability with a V-shape blade, using a sheet cutter made up of the interaction in the parallel displacement of a movable cutting member. The mechanism may have a V-shape format with the lower arc of the vertex facing the cutter edge to a fixed cutting base on a convex way.

[4] The US Patent No. 5584218 (SCHOENDIENST) relates to the cutting device which uses a couple of cutting blades arranged with the cutter edges in 'double V on opposite directions. The blades are arranged in such a way to provide two gradual cutting points of the edges until the blade vertexes meet. In order to act in this way, the document presents the structure of the convex surface blades made in thin, metallic, resistant, and flexible material, in such a way to withstand all cutting stages.

[5] The US Patent No. 5749277 (WALKER) describes the constructive aspects of the blades of a cutting mechanism for a receipt printer, made up of a V-shaped guillotine blade associated with a curved stationary blade, both with no inclination between themselves. The cutting process takes place by directing the guillotine blade against the stationary blade by means of a blade holder and the blade guide by a driving cam. [6] The US Patent 6405625 (NOMURA et al) discloses a printer equipped with a recording paper cutter with particularities of the cutting blade lengths. Such cutter consists of a rectilinear fixed blade, two movable blades, which as an assembly have a substantially V-shaped format. The movable blades, pressed by two springs, provide the effect of a bowed surface blade, due to the compressions on their axes. The cutting process occurs when the two movable blades are placed on a position opposite to the fixed blade, confronting on their cutting edges with the cutting edges of the fixed blade until the cut completion, by means of a driving mechanism. Such driving mechanism has a motor and a set of coupled gears in order to move the blades towards the cut direction via a directing pin, which causes the movable cutting blades to slide.

[7] The US Patent 6508600 (NONAKA) displays a printer with a cutting mechanism fitted with a rectilinear fixed blade associated with a V-shaped movable blade, incorporated into the printer body. The cutting process is performed through the displacement of the movable blade against the fixed blade, in such a way that the cut originates from the cutter edge to the cutting completion center. The driving mechanism consists of a motion motor and revolving gears interacting with a single central directing pin, which is responsible for the movable blade motion.

[8] The US Patent 6109154 (MIYATSU et al) also describes constructive arrangements where the two blades have an inclination between them aiming at an improved cut, as well as two constructive modes resulting in two contact points only between the cutting blades.

[9] The JP Patent Application publication No. 2001-347485 (KUNIAKI) describes a movable V-shaped cutting guillotine with a stationary rectilinear blade. The most relevant characteristics refer to the application of flexible blades, which interact upon one another, in a convex surface arrangement in the cutting compression process.

[ 10] Finally, The JP Patent Application publication No. 2002-273687 ( YUUICHI) displays the blade interaction where the cutting means are provided by an approximately convex edge movable blade and a rectilinear cutting base. Disclosure of Invention Technical Problem

[11] The solutions provided by the prior art have many problems.

[12] The mechanism described in the document US5090285 does not present any inclination on the positioning of one of the cutting blades, thus impairing the cutting since it provides an inaccurate finish on the material cut line. An alternative way seeking to correct this problem is described, with the existence of a portion projected on the vertex of the fixed base blade causing a central cutting effect; however, this arrangement causes a greater wear of the part in this area, reducing the blade lifetime. [13] The cutting device in 'double V disclosed in document US5584218, in spite of producing a more accurate cut, causes a greater wear on the material due to a greater friction of the cutter edges. In addition, the use of convex surface blades requires a greater constructive space, what makes the application of this device unfeasible on products requiring compact structures; and the use of convex cutter edges also causes an undesirable cut geometry variation.

[14] The movement device described in document US5749277, comprising s V-shaped guillotine blade associated with a curved stationary blade, is not indexed directly on the gear, and its drive is via the cam axle, so it is a complex mechanism. Besides, despite providing a cutting mechanism more compact than the documents already cited, this document presents a cutting process with no inclination of the stationary blade, what impairs the cut as it provides an inaccurate finish on the material cut line.

[15] The cutting blade described in the document US6405625 needs separate parts and blades to provide an improved cutting effect, which hamper a desired compaction of the mechanism. This need is due to the compression on the axle of the movable cutting blades in such a way to centralize the cutting pressure upon its completion, as well as the driving characteristic through a pin and gears coupled with the separate parts of the movable blades, generating excess constructive elements. In addition, as it is not fitted with any inclination, the fixed blade does not contribute to the cutting enhancement.

[16] In the document US6508600, the activation of the driving mechanism by a single central pin generates a single point for applying force on the movable blade, thereby increasing the risks of the movable blades self-locking onto the paper or the guide structure during the cutting process. With regard to the cutting effect, in the document referred to, despite the movable blade having a V-shaped aspect, the fixed blade does not describe a curvature on its cutter edge, as well as it is not contemplated any blade interaction inclination, and the result of the assembly is a poor cut and a stronger blade wear.

[17] The constructive arrangements described with the Patent US6109154 presents the application of double planes, or in arc, on blades whose constituent materials are extremely hard, making it more difficult for the production. In case of arc, there is also the undesirable effect of the cutting geometry variation and, in case of double planes, an equally undesirable exposed vertex is formed, particularly considering its production difficulty.

[18] Document JP2001347485 describes a movable V-shaped cutting blade configuration that provides a great wear of the cutter edges due to the blade interaction friction, as well as a not much compact arrangement for coupling the elements described in the cutting mechanism, in addition to producing the undesirable effect of the cutting geometry variation. [19] The document JP2002273687 describes the use of a blade with a convex cutter edge, and a small bowing, which is dependent on the material to be cut. The rectilinear blade has no curvature so that the initial adherence of the blades to the cutting material occurs from the center to the edges, without the stabilization of the cutting line by the edges, what impairs the cutting accuracy.

[20] As we can see from the aforementioned documents, there are various particularities as to the attempt to obtain an effective, aligned, and compact cutting system, such as for use on small-size printers and the equivalent. Nevertheless, the listed documents do not attain the best cutting mode due to the concurrent noninteraction of the aspects referring to an optimum cutting assembly in their solutions, such constructive modes also add disadvantages or extra production stages.

[21] The presented cutting device may have cutting blades with rectilinear cutter edge as opposed to the cutting blades with open or closed angular cutter edges. That is angles relative to the blade edge vertex with the shorter or greater arc, respectively, or on a more enhanced way. With both cutting blades with obtuse angle cutter edges, in the first instance they do not ensure an effective adherence of the cutting material to the blades and, in the second instance, they ensure the adherence and gradual cut in detriment to the blade wear, thus reducing their lifetime. Moreover, the documents do not present the compression of the movable blade central portion, not allowing for an improved effect on the cut completion. In other instances, the presented products do not have an inclination between the fixed and movable cutting blade surfaces, reason why they increase the material resistance when it is cut.

[22] With regard to the alignment system on the directing of the movable blade, some of the documents describe the driving process centrally performed, which may increase the risks of the movable blades self-locking onto the paper or the guide structure during the cutting process. Moreover, the single contact point of the movable blade against the fixed blade deteriorates the cut quality.

[23] Finally, the listed constructive aspects, such as the format of the blade faces and driving gear arrangements, present a complex manufacturing, and do not allow for compact formats of printers or the equivalent, for which the cutting mechanisms may be adopted.

[24] So, the need for mechanisms providing an enhanced cut with a reduced wear of the cutting blades remains, with an arrangement easy to industrialize and liable to a compaction. Technical Solution

[25] This invention aims at correcting the deficiencies of the arrangements on guillotine mechanisms and the respective production processes, with a new cutting assembly, which acts complementarily. The new cutting assembly define an excellent cutting quality via an angular constructive structure of the blades and by the way the movable blade is driven; as well as by the increased lifetime of the blades through a surface treatment of the blades being used; additionally resulting in a compact constructive form.

[26] In the first place, with regard to the blade arrangement, this invention discloses a 'double V shape blade. The vertex of a blade cutter edge forms a smaller angle, while the opposite vertex of the other blade cutter edge constitutes a greater angle, characterizing two overlapping V-shaped blades. Additionally to this geometry, an interaction angle between the faces of the cutting blades is also formed.

[27] In addition, even considering the blade lifetime as well as the compact form, it is possible to adopt softer steel in the manufacturing process, submitted to a plasma nitration treatment in order to increase the material surface hardness.

[28] The cutting effect due to the blade formats and arrangement results in an accurate cutting model applied on a guillotine apparatus. Besides, the present invention is fully adaptable to cutting mechanisms in a printer or in an equivalent device. This present invention also discloses arrangement for the indispensable parts such as blades, motor, and gears, in a compact way, including with the inclination of the fixed blade fitted into the related frame.

[29] The mechanism is externally fitted with guides projected on the insertion section, for example, for the paper to be cut, which contribute to the paper alignment in an improved way, in such a way to prevent a 'folding or jamming' effect of the paper, as well as an improvement of the interface with other coupled equipment, due to its novel constructive structure.

[30] The effect of the guillotine mechanism makes its applicability possible on devices where the blades separation in uncoupled blocks is desirable, for instance, like easy- load printers. Advantageous Effects

[31] Such 'double V shape, associated with the face inclination of one of the blades, makes it possible a cut in a more constant and accurate way, due to having only two contact points until the cut completion and a constant relative angle of the blades. If there were several contact points between the two blades, or even a surface or edge leaning on the other blade, it would be necessary to increase the force of the spring. This force compressing one blade against the other would have to be enough to shear the material being cut. This would increase the blade wear and reduce the cutting mechanism lifetime.

[32] The technical effect of the innovative cutting geometry of the present invention is a reduction in the blade wear by allowing the force pressing the two blades against themselves to be reduced. Such force necessary to perform the cut was reached by combining the 'double V, the angle between the blades, and the maintenance of these angles during the entire cutting, as the cutter edge is on a position of greater efficiency during the entire cutting. Therefore, the accurate cutting effect through the blades is attained on an improved way by this invention, extending the blade lifetime as they perform the cut on an enhanced way and with less stress.

[33] Furthermore, the present invention provides an enhanced cutting effect as a result of the arrangement of the spring which applies force on the center of the movable blade. In this way, the associated distribution of forces interacts with the fixed blade enabling a small pressure contact at the start of the cut and a greater one at the cut completion, thus minimizing the critical effort occurring on the central portion at the cut conclusion.

[34] The cut accuracy obtained by the constructive arrangement is incremented by the activation of the movable blade via two pins coupled with the gears. They prevent the rotation on the central axle direction and, consequently, avoid the blade self-locking, such as occurring on the cutting mechanism with a central pivot, thus contributing to keep the blades on the proper position from the beginning to the cutting edge, making lateral alignment guides unnecessary and determining a more compact and simple assembly.

[35] Softer steel can be adopted in the blades manufacturing process. The softer steel is submitted to a plasma nitration treatment in order to increase the material surface hardness, resulting in a significant increase of the blade edge resistance, as well as in a tooling savings during the production process, as the steel still presents a low hardness at the time the blades are stamped. Description of Drawings

[36] The object of the invention becomes perfectly understood in the following description with references to the indicative numerals in accompanying drawings, evidencing its main characteristics, as follows:

[37] Figure 1 - Top view of the greater angle cutter edge blade face.

[38] Figure 2 - Top view of the smaller angle cutter edge blade face.

[39] Figure 3 - Side view of the cutting blades with angular variations on the cutter edges.

[40] Figure 4 - Perspective view of the 'double V blades interacting with the compression spring force, in such a way to obtain two initial cutting contact points.

[41] Figure 5 - Perspective view of the 'double V blades interacting with the compression spring force, in such a way to obtain a cutting contact completion point.

[42] Figure 6 - Expanded perspective view of the parts of the guillotine in a compact mechanism attachable with printers or equivalent.

[43] Figure 7 - Posterior view of the supporting block with the components for the manual activation and alignment of the compact mechanism attachable with printers or equivalent.

[44] Figure 8 - Side view of the main supporting block with projected parts to the interfaces with other devices.

[45] Figure 9 - Top view of the main supporting block with projected parts to the interface with other devices. Mode for Invention

[46] According to the previous described drawings, a 'double V assembly arrangement is detailed in Figures 1 and 2. The cutting mechanism consists of two blades, with a first movable blade (1) and a second fixed blade (2). The second blade is arranged in such a way to provide an angular inclination (b) with the first blade as in Figure 3. The fixed blade (2) in particular has a vertex (4) on the edge (3) with an angle (a) and a short distance (u), that is a projection of the distance between the vertex (4) and the blade lateral edge. The movable blade (1) in particular has a vertex (6) on the cutter edge (5) with an angle (r), which is smaller than (a), and a distance (v) that is a projection of the distance between the vertex (6) and the blade lateral edge. This projection (v) is quite bigger than the distance (u) of the fixed blade.

[47] In addition, aiming at increasing the blade lifetimes associated with the cut quality, alternative arrangements are disclosed. In Figure 3 alternative arrangements are represented with cutting faces and variation of the cutter edge angles (d) and (g) dependent on the resistance of the material to be cut, and the angle (b) formed by the inclination between the two surfaces of the fixed (2) and movable (1) blades.

[48] The combination of the geometry of the 'double V shaped blades associated with the inclination between the blades (b), as in Figures 3, 4 and 5, causes the two blades to touch only on two points (PI) and (P2), which are symmetrically distant from one another relative to the blades central symmetry line. As the movable blade moves towards the fixed blade to perform the cut, the two contact points keep moving symmetrically towards the blade center. When the two contact points meet, the complete cutting of the material being cut occurs. The blade movement is shown with the sequence of Figures 4 and 5. The required force to keep the two blades pressed to one another is provided by means of a clamping spring (7) supported in one side on the center of the movable blade and, in the other, on the mechanism cover.

[49] As the cutting apparatus is fully adaptable to and coupled with the printing mechanism of a printer or the equivalent. Figures 6, 7, 8 and 9 represent an applicable constructive arrangement regarding the characteristics of the innovative cutting constructive geometric enhancement and process means involved, as well as the desirable compaction, by coupled parts. This coupled parts comprise movable blade (1), fixed blade (2), fixed blade cutter edge (3), movable blade cutter edge (5), clamping spring (7), driving pins (8), DC motor (9), helical gears (10), and worm gear (11), in a compact way, input guide (12), secondary frame (13) of the cutting block assembly, and recess (14) in order to have the desired inclination (b) of the fixed blade molded by the related secondary frame, not requiring the use of external attachment elements. The cutting mechanism is attached to the main frame (15) of the cutting block assembly. Moreover, the cutting mechanism has a paper alignment interface (16) on the outside portion of the frame referred to, which has a structure defined by projected portions (17) arranged alternately and symmetrically all along the paper interface width, constituting the paper output opening which improves the interface with other mechanisms, as it prevents any 'folding or jamming' effect from occurring. The main frame has an opening (18) and a projected portion (19), internally molded, in order to serve as a fitting and support for the motor, and openings (20) to serve as fitting of the spring sides; and, additionally, coupling portions (21) for fitting into the secondary frame.

[50] The mechanism is characterized by being made within the arranged cut geometry, with the displacement of the V-shaped movable blade (1) with an angle (r), as opposed to the larger vertex (4) angle (a) on the fixed blade (2), and with an inclination (b). This arrangement is described in Figures 1, 2, and 3, with the movement characteristics in Figures 4 and 5. It is particularly used on the guillotine mechanism for printers or the equivalent, according to Figure 6. The movable blade (1) motion is made by two driving pins (8), juxtaposed at symmetrical distances and fitted into the two horizontal oblong holes (22), which convey the movement provided by the helical gear assembly (10), and are moved alternately by worm gear (11) driven by the DC motor (9). The gears revolve on two fixed axles on a main supporting block (15), together with the other constructive elements, thus determining - via the oblongs on the pin fitting horizontal plane - the routing of the movable blade in a stabilized way against the cutting fixed blade in such a way to interact with the material to cut. Once the movable blade is activated in the cutting process, the movable blade edge edges (5) initially meet the fixed blade edge (3) which, in turn, has a constructive inclination (b) so as to interact from the beginning to the cutting edge. Only two initial contact points perform the displacement of the cutting blades with a force initially applied by the spring, as in Figure 4, going towards the material to be cut, and with a successively increasing compression until the cutting completion.

[51] Alternatively, the rotational movement of the worm gear can be manually made via an opening (24) on the main frame. It could be necessary during paper release operation. The opening (24) is arranged in such a way to allow for the exposure of a projected portion (23) of the worm gear (11). Industrial Applicability [52] The cutting effect of the interaction geometry between a inclined blade and a reference blade creating enhanced cutting angles, such as described in Figures 1, 2, and 3, and the consequential cutting effect as to the interaction of the formats of moving blades as complementarily described in Figures 4 and 5, associated with the particular arrangements of this assembly, result in the best cutting model applied on a cutting mechanism. Among the innumerous ways to perform this cut effect are those mechanisms combining the distinctive format of the cut interaction in 'double V with the inclination (b) between the movable blade and the fixed blade, with the edge angle (d) and (g) of blades, to the thickness and composition of the material used in order to be cut. Besides, the mechanism has as a result the associated effect of the cut enhancement with an industrial applicability.

[53] In addition, during the manufacturing process of the sectioning mechanism, a stamping stage of blades (1) and (2) is contemplated. This stage employs a steel less hard than those commonly used in this kind of application, and subsequently to such stage a blade surface treatment process is applied by plasma nitration. In this way, the plasma parameters such as electron density, energy, and distribution function are controlled to vary the film properties to obtain a extremely hard blade and, consequently, a smaller wear of the cutter edge.

Claims

[1] 01. 'CONSTRUCTIVE ARRANGEMENTS ON SECTIONING MECHANISMS', characterized by the geometric arrangement of the 'double V assembly; a blade (1) has vertex (6) with an angle (r) on the cutting edge and distance (v) relative to the projections of the cutting edges; and another, blade (2), has vertex (4) with an angle (a), larger than angle (r), on the cutting edge and distance (u) relative to the projections of the cutting edges; and a relative inclination angle (b) between the two blades.

[2] 02. 'CONSTRUCTIVE ARRANGEMENTS ON SECTIONING MECHANISMS', according to claim 01, characterized b blades with edge angle (d) and (g), defined according to the material to be cut and according to the desired blade lifetime.

[3] 03. 'CONSTRUCTIVE ARRANGEMENTS ON SECTIONING MECHANISMS', according to claim 01, characterized by being applied on printers or equivalent device, with an arrangement of main frame (15) and secondary frame (13) with molded parts (18), (19), (20), (24), in such a way to receive the drive motor (9), gear (11), compression spring (7) and blades (1) and (2), and coupling parts (21).

[4] 04. 'CUTTING MECHANISMS', according to claim 03, characterized by an alignment interface (16) for the paper to be cut, through projected alternate parts (17).

[5] 05. 'CONSTRUCTIVE ARRANGEMENTS ON SECTIONING MECHANISMS', according to claim 03, characterized by a notch arrangement for interface with blocks and printers for coupling or uncoupling, and parts for fitting (21) the main frame (15) to the secondary frame (13).

[6] 06. 'CONSTRUCTIVE ARRANGEMENTS ON SECTIONING MECHANISMS', characterized by an interaction process between a blade (1), which has vertex (6) with an angle (r) on the cutting edge and distance (v) relative to the projections of the cutting edges, confronting with another blade (2), which has vertex (4) with an angle (a), larger than angle (r), on the cutting edge and distance (u) relative to the projections of the cutting edges ; during the interaction process the two contact points provide the same inclination angle (b) relative to the two cutting blade faces from the beginning to the end of the cutting.

[7] 07. 'CONSTRUCTIVE ARRANGEMENTS ON SECTIONING MECHANISMS' according to claim 06, characterized by a process in which the spring (7) is applied to the center of the movable blade (1), and associate the dis- tribution of forces interacting with the fixed blade (2), determining a pressure contact from the beginning to the end of the cutting.

[8] 08. 'CONSTRUCTIVE ARRANGEMENTS ON SECTIONING MECHANISMS', characterized by a process comprising a stamping stage of the cutting blades (1) and (2), wherein the metal used is less hard; and a subsequent stage, wherein the surface plasma nitration treatment is used.

[9] 09. 'CONSTRUCTIVE ARRANGEMENTS ON SECTIONING MECHANISMS', according to claim 06, characterized by a production process and resulting product, which comprises a stamping stage of blades (1) and (2); and a subsequent stage, when they go through a surface treatment with a plasma nitration process.