JP4438639B2 - Printer - Google Patents

Description

  The present invention relates to a printer that records on a sheet material such as roll paper or folded continuous paper, and more particularly to a printer that includes a sheet cutting device that cuts a sheet material.

  2. Description of the Related Art Conventionally, as this type of sheet cutting apparatus, a device that cuts a sheet by reciprocating a movable blade with respect to a fixed blade and causing the blades to cross each other while sliding is widely known. As a printer provided with such a sheet cutting device, there is a thermal printer described in Japanese Patent Application Laid-Open No. 11-123692.

  A configuration example of a thermal printer including a conventional sheet cutting device will be described with reference to FIGS. 2 and 3. FIG. 2 is a side view showing a schematic configuration of a thermal printer including a conventional sheet cutting apparatus. FIG. 3 is a perspective view schematically showing the sheet cutting apparatus of FIG.

  A conventional thermal printer 101 shown in FIG. 2 includes a sheet cutting device 105 on an upper portion of a printing unit 104 having a printing thermal head 102 and a platen roller 103. Printing is performed when a sheet material S such as roll paper to be printed passes between the printing thermal head 102 and the platen roller 103 from the lower part of the printer by the rotation of the platen roller 103. The printed sheet material S is sent to the sheet cutting device 105 and cut into a predetermined length.

  The sheet cutting device 105 includes a fixed blade unit 106 and a movable blade unit 107. The fixed blade unit 106 is provided on the fixed blade 108, the base 109, and the base 109, and supports a support portion 110 that rotatably supports the end of the fixed blade 108 opposite to the cutting edge, and the fixed blade And a spring member 111 for biasing the fixed blade 108 provided between the base 108 and the base 109 upward. On the other hand, the movable blade unit 107 includes a movable blade 112 and a slide mechanism 113 that can slide the movable blade 112 horizontally toward the fixed blade 108 side.

  As shown in FIG. 3, the movable blade 112 has an appearance in which the blade is recessed in a substantially V shape, and is reciprocated toward the fixed blade 108 by the slide mechanism 113.

The upper surface of the fixed blade 108 is positioned above the lower surface of the movable blade 112 by the biasing force of the spring member 111 in a state where the calling portion 114 formed at the tip of the movable blade 112 does not overlap the fixed blade 108. Yes. Therefore, when the movable blade 112 is moved to the fixed blade 108 side by the slide mechanism 113 and rides on the fixed blade 108 at the calling portion 114 and overlaps, the fixed blade 108 resists the urging force of the spring member 111 and its protrusion amount. Is retracted only (state of FIG. 2). A contact pressure equal to the reaction force of the spring member 111 acts between the blades of the movable blade 112 and the fixed blade 108. When the movable blade 112 moves on the upper surface of the fixed blade 108 in this state, the sheet material S intervening between the movable blade 112 and the cutting edge of the fixed blade 108 is cut.
JP 11-123692 A

  The conventional configuration shown in FIGS. 2 and 3 has a problem that the number of parts increases because a spring member and a base for disposing the spring member are required below the fixed blade.

  Further, a thermal printer provided with a sheet cutting device generally has a sheet cutting device provided on the downstream side in the sheet conveying direction with respect to the printing unit. Due to this configuration, the printing position of the printing unit (position A in FIG. 2). The area from the cutting position to the cutting position by the sheet cutting device (position B in FIG. 2) is an unprinted area. As described above, it is essential to dispose the spring member and the base under the fixed blade. Therefore, a distance corresponding to the disposition of these components is required, and a relatively long unprinted area can be formed on the print head of the sheet material. It was. For this reason, there is a case where the user is required to control the front end of the sheet material to be retracted from the cut position to the print position side.

  Conventionally, a spring member such as a coil spring or a leaf spring is used as an upward biasing means for the fixed blade, and the fixed blade is pushed up at several points (see FIG. 3). In this method, the fixed blade is pushed up with a distributed load with respect to the longitudinal direction of the movable blade, so that the contact pressure between the blade edges becomes non-uniform with respect to the longitudinal direction of the blade, and the cutting quality for each cutting is improved. Sometimes it was not stable.

  SUMMARY OF THE INVENTION In view of the above-described problems of the prior art, the present invention provides a thermal printer including a sheet cutting device that can reduce the number of parts, narrow an unprinted area, and stabilize cutting quality. is there.

In order to achieve the above object, the present invention is directed to a thermal print head and the print thermal head, and conveys the sheet material while contacting the heat sensitive sheet material to the heat generating portion of the print thermal head. A platen roller, a fixed blade, and a movable blade that slides toward the fixed blade, and the sheet material conveyed from the platen roller is cut when the fixed blade intersects the movable blade. In a printer including a sheet material cutting device, the platen roller has an outer peripheral portion formed of an elastic body, and the fixed blade is pivotally supported so that an end opposite to the blade formed at the tip is rotatable. by being arranged such that the longitudinal direction over the entire surface of the lower surface is touch evenly against the outer peripheral surface of the platen roller across the width of the platen roller, the movable blade, the sheet material To overlap rides on the upper surface opposite to the lower surface of the front Symbol fixed blade when cutting has attracting portions formed at the tip of the fixed blade side, the sheet material cutting device, the sheet material When the movable blade is slid to the fixed blade side and rides on the fixed blade at the calling portion at the tip and overlaps, the fixed blade is provided on the outer peripheral portion of the platen roller. The elastic body is pressed against the platen roller against the elastic force of the elastic body, and the reaction force of the pressed elastic body causes a contact pressure between the fixed blade and the movable blade, and is pressed against the platen roller. The fixed blade is configured such that it receives a uniform elasticity from the platen roller over the entire surface in the longitudinal direction, and the contact pressure is uniformly applied in the longitudinal direction of the blade .

In the printer configured as described above, the number of parts is reduced by arranging the fixed blade directly on the outer peripheral surface of the platen roller without arranging the spring member or the base on the lower surface side of the fixed blade as in the past. At the same time, the space or gap on the lower surface side of the fixed blade can be reduced. For this reason, cost reduction and size reduction can be achieved.

Furthermore, since the longitudinal entire lower surface of the fixed blade is in contact with the outer peripheral surface of the conveying roller, the fixed blade that is pushed down by the movement of the movable blade during cutting of the sheet material is uniform in the longitudinal direction over the entire surface of the platen roller A uniform contact pressure acts in the longitudinal direction of the blade even between the blade edges of the fixed blade and the movable blade. For this reason, there is an effect that the cutting quality is stabilized every time the sheet material is cut.

Further, in the printer of the present invention (the thermal printer of FIG. 1), the fixed blade is disposed directly on the outer peripheral surface of the platen roller, so that the distance that becomes an unprinted area from the printing position to the cutting position by the sheet cutting device. Can be made shorter than the printer configuration shown in FIG. For this reason, the degree of freedom of printing is improved, and the sheet material can be saved.

  As described above, according to the present invention, it is possible to reduce the cost and size by reducing the number of parts. Further, the contact pressure between the blades of the fixed blade and the movable blade is made uniform in the longitudinal direction of the blade, so that the cutting quality can be stabilized.

  Further, in a printer in which a thermal head is arranged with respect to the conveyance roller, an unprinted area can be reduced, and the degree of freedom in printing and saving of sheet material can be achieved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a side view showing a schematic configuration of a thermal printer according to an embodiment of the present invention.

As shown in FIG. 1, the thermal printer 1 of the present embodiment has a printing thermal head 2 as a printing unit and a sheet while a heat-sensitive sheet material S is in contact with a heat generating unit (not shown) of the thermal head 2. and a platen roller 3 for transporting the wood S. A sheet cutting device for cutting the printed sheet material to an arbitrary length is installed downstream of the printing unit made of such components in the sheet material conveyance direction. The platen roller 3 has an elastic body such as rubber around the shaft.

  The sheet cutting apparatus has a fixed blade 4 and a movable blade 5 that intersect each other.

  The end of the fixed blade 4 opposite to the cutting edge is rotatably supported by the support portion 6. As a result, the fixed blade 4 is rotatable about the support portion 6, and the lower surface of the fixed blade 4 is in contact with the outer peripheral surface of the upper portion of the platen roller 3. At this time, the lower surface of the fixed blade 4 is in uniform contact over the width direction of the platen roller 3.

  The movable blade 5 can be horizontally slid toward the fixed blade 4 by the slide mechanism 7. Similar to the movable blade 112 shown in FIG. 3, the movable blade 5 has an appearance in which the blade is recessed in a substantially V shape. On the other hand, the tip of the fixed blade 4 has a straight blade edge. As the slide mechanism 7, a mechanism that converts the rotational force of the motor into a linear motion by a gear or a link mechanism and moves the movable blade 5 back and forth is applied.

  Furthermore, the blade tip position on the upper surface of the fixed blade 4 is located above the lower surface of the movable blade 5 in a state where the calling portion 8 formed at the tip of the movable blade 5 does not overlap the fixed blade 4. The calling portion 8 protrudes from both sides of the movable blade 5 in the width direction, and has a shape in which the lower surface of the protruding portion is bent upward (see the calling portion 114 in FIG. 3).

  Next, the operation at the time of sheet cutting by the thermal printer 1 will be described.

  When the movable blade 5 is moved to the fixed blade 4 side by the slide mechanism 7 and rides on and overlaps the fixed blade 4 at the calling portion 8 at the tip, the fixed blade 4 is elastic of rubber provided on the outer periphery of the platen roller 3. It is pushed down by the amount of protrusion against the force (state of FIG. 1). Then, the contact pressure acts between the blade edges of the fixed blade 4 and the movable blade 5 by the reaction force of the pushed down rubber.

  When the movable blade 5 moves on the upper surface of the fixed blade 4 in this state, the sheet material S intervening between the blade edges of the fixed blade 4 and the movable blade 5 is cut.

  In the thermal printer described above, since the entire longitudinal surface of the lower surface of the fixed blade 4 is in contact with the outer peripheral surface of the platen roller 3, the fixed blade 4 pushed down by the sliding movement of the movable blade 5 when the sheet material is cut is The platen roller 3 receives a uniform elasticity over the entire surface in the longitudinal direction, and a uniform contact pressure acts in the longitudinal direction of the blade between the blade edges of the fixed blade 4 and the movable blade 5. For this reason, there is an effect that the cutting quality is stabilized every time the sheet material is cut.

  Further, since the fixed blade 4 fixed so as to rotate about the rear one point at the support portion 6 is arranged so that the back surface of the fixed blade 4 is in contact with the outer peripheral surface of the platen roller 3, the printing position (FIG. 1). The distance that becomes the unprinted area from the position A) to the cutting position (position B in FIG. 1) by the sheet cutting device can be made shorter than that in the printer configuration shown in FIG. For this reason, the degree of freedom of printing is improved, and the sheet material can be saved.

  Further, the platen roller 3 is arranged so as to be in direct contact with the lower surface of the fixed blade 4 without arranging the spring member and the base on the lower surface thereof. Lower space and gap can be reduced. For this reason, cost reduction and size reduction can be achieved.

  Note that the sheet cutting device including the fixed blade 4 and the movable blade 5 of the thermal printer described above can be applied to a portion other than the downstream in the sheet material conveying direction of the printing unit having the printing thermal head 2 and the platen roller 3. it can. That is, instead of the printing unit described above, a conveyance unit including a conveyance rubber roller and a spur is arranged, and in the printer including the print head upstream of the conveyance unit in the sheet material conveyance direction, the fixed blade as in the above embodiment. The structure which has arrange | positioned 4 so that the outer peripheral surface of the rubber roller for conveyance may be considered can be considered. The concept of the printer includes, for example, an ink jet printer other than the thermal printer.

  In addition, although the blade of the movable blade 5 is shown in a V-shaped shape, the present invention is not limited to this shape, and the blade of the movable blade is formed linearly or obliquely, for example. The present invention can also be applied to such a case.

1 is a side view showing a schematic configuration of a thermal printer according to an embodiment of the present invention. It is a side view which shows schematic structure of the printer containing the conventional sheet cutting device. It is a perspective view which shows typically the sheet | seat cutting device of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Thermal printer 2 Thermal head for printing 3 Platen roller 4 Fixed blade 5 Movable blade 6 Support part 7 Slide mechanism 8 Calling part A Print position B Cut position S Sheet material

Claims (3)

A printing thermal head, a platen roller that is disposed opposite to the printing thermal head, and conveys the sheet material while bringing the heat-sensitive sheet material into contact with the heat generating portion of the printing thermal head , a fixed blade, and the fixed blade In a printer comprising a movable blade that slides toward the side, and a sheet material cutting device that cuts the sheet material conveyed from the platen roller by intersecting the fixed blade and the movable blade ,
The platen roller has an outer peripheral portion formed of an elastic body,
The fixed blade, the edge formed at the tip end portion on the opposite side is rotatably supported, uniformly on the outer peripheral surface of the platen roller in the longitudinal direction over the entire surface of the lower surface across the width of the platen roller arranged as to come in contact,
The movable blade such that said overlap rides on the upper surface opposite to the lower surface of the front Symbol fixed blade when cutting the sheet material has an attracting portion formed at the tip of the fixed blade side,
In the sheet material cutting device, when the sheet cutter is cut, the movable blade is slid and moved to the fixed blade side and rides on and overlaps the fixed blade at the leading portion of the tip. The platen roller is pressed against the platen roller against the elastic force of the elastic body provided on the outer peripheral portion of the platen roller, and the reaction force of the pressed elastic body causes a gap between the fixed blade and the movable blade. The fixed blade pressed by the contact pressure is configured to receive the elastic force uniformly from the platen roller over the entire surface in the longitudinal direction so that the contact pressure is uniformly applied in the longitudinal direction of the blade. Printer. The printer according to claim 1, wherein the calling portion of the movable blade is formed on both sides of the movable blade in the width direction so as to protrude from the blade . The printer according to claim 1 , wherein the movable blade is formed in a shape in which the blade is recessed in a V shape .

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