CN210821420U

CN210821420U - Thermal head and printing equipment

Info

Publication number: CN210821420U
Application number: CN201921005731.XU
Authority: CN
Inventors: 不公告发明人
Original assignee: Xiamen Hanyin Electronic Technology Co Ltd
Current assignee: Xiamen Hanyin Co ltd
Priority date: 2019-06-28
Filing date: 2019-06-28
Publication date: 2020-06-23
Anticipated expiration: 2029-06-28

Abstract

The utility model relates to a thermal head and printing apparatus, wherein the thermal head contains: a base having a support surface on the upper side, a plurality of heating resistors supported on the support surface, and a plurality of pairs of electrodes; a pair of electrodes for supplying power to the heating resistors are electrically connected to both ends of each heating resistor in the first direction; the heating resistor body is provided with a heating part and two electric connecting parts which are positioned at two ends of the heating part along a first direction; the heating part comprises a rectangular heating main body area and compensation areas which are arranged at two ends of the heating main body area along a first direction, the compensation areas are symmetrically distributed along a central axis, and the central axis extends along the first direction. The compensation region is provided to extend the length of the heating resistor extending in the first direction, and when the energization energy of the electrodes connected to the electrical connection portion is uniform, the heat generation amount of the portion of the heating resistor having the longer length is smaller, so that the shape of the heat region through which the energization heat of the heating portion is transmitted is close to a rectangle.

Description

Thermal head and printing equipment

Technical Field

The utility model relates to a print technical field, concretely relates to thermal head and printing apparatus.

Background

Thermal heads have been used in thermal printers for printing on thermal recording media such as paper by selectively driving a plurality of heating elements based on print data. Referring to fig. 1, the thermal head has a base and a heating resistor on the base, and a pair of electrodes connected to both ends of the heating resistor are used to supply power to the heating resistor, so that the heating resistor generates heat, and printing can be performed on a printing medium.

The desired print effect of the thermal head is shown as desired print effect S1 in fig. 3, where each desired print dot has a rectangular configuration. However, in the prior art, the actual printing effect is as shown in the actual printing effect S2 in fig. 3, the actual printing effect of each printing dot is in an approximately elliptical shape, and a large gap is generated between the printing dots in the elliptical shape. Therefore, the actual printing effect of the conventional thermal head leaves a blank gap between the printing dots.

Disclosure of Invention

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a thermal head capable of reducing a gap between a printing point of the thermal head and a printing point.

Specifically, the utility model provides a thermal head contains: a base having a support surface on the upper side, a plurality of heating resistors supported on the support surface, and a plurality of pairs of electrodes; a pair of electrodes for supplying power to the heating resistors are electrically connected to both ends of each heating resistor in the first direction; the heating resistor body is provided with a heating part and two electric connecting parts which are positioned at two ends of the heating part along a first direction; the heating part comprises a rectangular heating main body area and compensation areas which are arranged at two ends of the heating main body area along a first direction, the compensation areas are symmetrically distributed along a central axis, and the central axis extends along the first direction.

Preferably, the central axis is located at an intermediate position of the heating portion along a second direction, wherein the second direction is orthogonal to the first direction.

Preferably, the heating portion includes a first boundary adjacent to the electrode, the first boundary includes a first arc edge protruding toward the electrode side along a first direction, and two ends of the first arc edge are connected to two second boundaries of the heating portion in a second direction; wherein the second direction is orthogonal to the first direction.

Preferably, the first boundary includes first sides extending along the second direction, and two ends of each of the first sides are respectively connected to the first arc side and the second boundary.

Preferably, the heating portion includes a first boundary adjacent to the electrode, the first boundary includes two second sides extending toward the electrode, and one end of each of the two second sides is connected to each of two second boundaries of the heating portion in the second direction.

Preferably, the two second sides are inclined towards the central axis from the electrode direction, and the second sides are intersected with the central axis.

Preferably, the other ends of the two second sides are respectively connected to two ends of a third side.

Preferably, the second side is parallel to the first direction.

Preferably, the first boundary includes first sides extending along the second direction, and two ends of each of the first sides are respectively connected to the second sides and the second boundary.

The present application further provides a printing apparatus comprising any of the thermal heads described above; and a pressing mechanism for conveying and pressing the printing medium and the thermal head together.

By adopting the technical scheme, the utility model discloses can gain following technological effect:

1. the utility model provides a thermal head, the heating part of which comprises a heating main body area with a rectangular structure and compensation areas which are arranged at the two ends of the heating main body area along a first direction, when the heating shape of the heating main body area is approximately elliptical, the compensation area is used for prolonging the length of the heating resistor body extending along the first direction, when the conduction energy of the electrodes connected to the electrical connection portion is uniform, the amount of heat generation is smaller in the portion where the length of the heating resistor is longer, and therefore, in the actual situation that the compensation area is positioned at the middle position of the heating resistor body along the second direction, and the heat dissipation capacity of the heating part at the two ends along the second direction is more than that of the middle position, the shape of the heat area of the heating part for the conduction heating transmission is close to the rectangle, and then reach the technical problem who solves the blank clearance between printing point and the printing point great among the prior art.

2. The utility model provides a pair of thermal head, heating portion on the heating resistor body contain and border on in the first border of electrode, first border includes along first direction to the convex first arc limit of electrode side, the both ends on first arc limit connect in heating portion two second borders on the second direction, to the heating resistor body of the peak of the convex first arc limit of electrode side extend the longest on first direction, and its heating resistor body of connecting in second border department extends the shortest on first direction, can make the calorific capacity of heating resistor body evenly increase by middle to both sides through the arc transition, and the variation of the curvature control calorific capacity of accessible arc limit.

Drawings

FIG. 1 depicts a schematic diagram of a thermal head of the prior art;

FIG. 2 depicts a schematic structural view of a thermal head of the present invention;

FIG. 3 depicts a schematic of a desired printing effect, an actual printing effect of the prior art, and a printing effect of the thermal head of the present invention;

FIG. 4 depicts a schematic view of a sectioning structure of a thermal head of the present invention;

fig. 5 to 7 are schematic views illustrating heating portions of different structures according to a first embodiment of the present invention;

fig. 8 is a schematic structural view of a heating portion according to a second embodiment of the present invention.

Reference symbols of the drawings

1-base, 2-heating resistor body, 21-heating main body area, 22-compensation area, 23-first boundary, 231-first arc edge, 232-first side edge, 233-second side edge, 234-third side edge, 24-second boundary and 3-electrode.

Detailed Description

To make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the drawings of the embodiments of the present invention are combined to clearly and completely describe the technical solutions of the embodiments of the present invention, and obviously, the described embodiments are some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention. Thus, the following detailed description of the embodiments of the present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "upper end", "lower end", "upper section", "lower section", "upper side", "lower side", "middle", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like indicate the orientation or positional relationship indicated based on the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the equipment or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.

Furthermore, the terms "parallel," "perpendicular," "orthogonal," and the like are used in a relative context (e.g., substantially parallel, substantially perpendicular, substantially orthogonal) only, and are not to be construed as geometrically absolute unless otherwise explicitly limited.

The structure and function of the solution of the present application will now be described in detail with reference to fig. 1 to 8.

A first embodiment of the present invention provides a thermal head for use in a thermal printer (not shown). The thermal printer (i.e. printing equipment) comprises a bracket, a roller mechanism, a thermal head, a pressing mechanism and a driving mechanism which takes a motor as a driving force to drive a printing medium to move forwards. The roller mechanism, the thermal head, the pressing mechanism and the driving mechanism are arranged on the bracket. The roller mechanism has a platen roller, the outer peripheral surface of which is disposed opposite to the thermal head with a passage for the print medium to pass through, and the platen roller and the thermal head clamp the print medium therebetween with a predetermined pressure under the pressure of the pressing mechanism, so that the thermal head prints on the print medium.

Referring to fig. 4, the thermal head of the present invention includes a base 1, a plurality of heating resistors 2, and a plurality of pairs of electrodes 3. The upper side of the base 1 has a support surface on which a plurality of heating resistors 2 are supported. Referring to fig. 1, in the prior art, each of the heating resistors 2 is connected to an electrode 3 at each of two ends along the first direction, the two electrodes 3 have a predetermined distance therebetween, and a pair of the electrodes are disposed opposite to each other to supply power to the heating resistor 2 electrically connected to the electrodes, so that the heating resistor 2 generates heat to print on a printing medium. It is understood that each electrode 3 is electrically energized and when energized, a current can be caused to flow through the heating resistor body 2. The heating resistor 2 includes a first electrical connection portion, a second electrical connection portion, and a heating portion interposed between the first electrical connection portion and the second electrical connection portion in the first direction. The heating unit prints on a print medium clamped between the thermal head and the platen roller. The plurality of heating resistors 2 are arranged in a linear array in the second direction. And during printing, the thermal head actively prints one line along the second direction, the motor on the printing equipment controls the printing medium to move forwards, and the printing head continuously actively prints along the second direction, and the steps are repeated until the printing is finished. Wherein the first direction is orthogonal to the second direction.

In the embodiment of the present invention, referring to fig. 2, the heating portion includes a heating main body area 21 and a compensation area 22, the heating main body area 21 is rectangular, and the compensation area 22 is located at two ends of the heating main body area 21 along a first direction. The compensation zones 22 are symmetrically distributed along a central axis extending in a first direction. The central axis is located at an intermediate position of the heating portion in the second direction.

In the prior art, the actual printing effect is as shown in fig. 3, and the inventors found that the reason for this is that the heat dissipation rate is faster at the positions closer to the two second boundaries 24 at the two ends of the heating resistor body 2 in the second direction, and the heat dissipation rate is faster at the intermediate position farther from the heat generating portion. Therefore, in the present application, the compensation regions 22, which are specifically configured to compensate for the energizing length (i.e., the resistance), are disposed at two ends of the rectangular heating body region 21 along the first direction. In the case where the energization energy of the electrodes 3 connected to the electrical connection portion is uniform, the heating resistor 2 has a smaller amount of heat generation at the longer portion, and therefore, the heat generation amount is distributed in a state where the heat generation amount gradually decreases from the middle to both sides, and in the actual case where the amount of heat radiated from both ends of the heating portion in the second direction is larger than the amount of heat radiated from the middle position, the shape of the heat region to which the energization heat generation of the heating portion is transmitted is made to approach a rectangle, as shown in the actual printing effect S3 in fig. 3, thereby achieving a solution to the technical problem of the prior art that the blank gap between the printing dot and the printing dot is large.

In the embodiment of the present invention, referring to fig. 5, the heating portion includes a first boundary 23 adjacent to the electrode 3, the first boundary 23 includes a first arc edge 231 protruding toward the electrode 3 along the first direction, and both ends of the first arc edge 231 are connected to two second boundaries 24 of the heating portion in the second direction. The highest point of the first curved edge 231 is located on the central axis. The heating resistor body at the highest point of the first arc edge 231 protruding toward the electrode 3 extends longest in the first direction, and the heating resistor body connected to the second boundary 24 extends shortest in the first direction, so that the amount of heat generated by the heating resistor body 2 can be uniformly increased from the middle to both sides by arc transition, and the amount of change in the amount of heat generated can be controlled by the curvature of the arc edge.

Specifically, in the present embodiment, the two electrodes 3 of the electrical connection portion electrically connected to the two ends of the heating resistor 2 in the first direction respectively have first end portions, the first end portions are disposed oppositely along the first direction, the two first end portions respectively include hollow areas, and the two hollow areas on the pair of electrodes 3 respectively extend in a direction away from each other. The hollowed-out region is used to expose the compensation region 22. It will be appreciated that the compensation zone 22 communicates with the heated body zone 21.

Unlike the present embodiment, in another embodiment, referring to fig. 6, the first boundary 23 includes two second sides 233, and one ends of the two second sides 233 are respectively connected to the two second boundaries 24 of the heating portion in the second direction. Wherein the two second sides 233 are a straight line. Preferably, the other ends of the two second sides 233 intersect at the central axis. It is understood that the other ends of the two second sides 233 can be connected to two ends of a third side 234, respectively, and the third side 234 is a straight line extending along the second direction.

It is understood that the first arc edge 231, the second side edge 233 and the third side edge 234 of the heat generating portion are boundary edges of the compensation region 22 and the electrode 3.

Preferably, the extension of the compensation zone 22 in the first direction is not greater than the extension of the heating resistor body in the first direction. It is understood that if the length of the compensation region 22 extending in the first direction is longer, the amount of heat generation decreases too much at the longer length on the heating resistor body 2.

Unlike the first embodiment, the present application provides a second embodiment, in which, referring to fig. 7, the first boundary 23 includes a first side 232 extending along the second direction, one end of the first side 232 is connected to the first arc edge 231 or the second side 233, and the other end is connected to the second boundary 24. The first side 232 is an interface between the heating body region 21 and the electrode 3, the first arc 231 or the second side 233, and is an interface between the compensation region 22 and the electrode 3. It can be understood that by controlling the extension length of the first side 232 along the second direction, the area of the heating resistor 2 along the second direction without increasing the compensation area 22 can be controlled, so as to achieve the purpose of accurately controlling the shape of the heat area transferred after the heating resistor 2 is heated by electricity.

It is understood that when the first boundary 23 of the present embodiment is a structure including the first side 232 and the second side 233, the second side 233 may be a straight line parallel to the first direction. Other characteristics not mentioned in the second embodiment may be the same as those of the first embodiment, and the alternative implementation and the advantages thereof may also be the same as those of the first embodiment, and thus are not described again.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A thermal head, comprising: a base having a support surface on the upper side, a plurality of heating resistors supported on the support surface, and a plurality of pairs of electrodes; a pair of electrodes for supplying power to the heating resistors are electrically connected to both ends of each heating resistor in the first direction; the heating resistor body is provided with a heating part and two electric connecting parts which are positioned at two ends of the heating part along a first direction;

the heating device is characterized in that the heating part comprises a rectangular heating main body area and compensation areas which are arranged at two ends of the heating main body area along a first direction, the compensation areas are symmetrically distributed along a central axis, and the central axis extends along the first direction.

2. A thermal head according to claim 1, wherein said central axis is located at an intermediate position of the heating portion in a second direction orthogonal to said first direction.

3. A thermal head according to claim 2, wherein said heating portion includes a first boundary adjacent to said electrode, said first boundary including a first arc edge projecting toward the electrode side in the first direction, both ends of said first arc edge being connected to two second boundaries of said heating portion in the second direction.

4. A thermal head according to claim 3, wherein said first boundary comprises first sides extending in a second direction, and each of said first sides has two ends connected to said first arc side and said second boundary, respectively.

5. A thermal head according to claim 2, wherein said heating portion includes a first boundary adjacent to said electrode, said first boundary includes two second sides extending in the direction of the electrode, and one end of each of said two second sides is connected to each of two second boundaries of said heating portion in the second direction.

6. A thermal head according to claim 5, wherein said second sides are inclined towards the central axis in the direction of the electrodes and said second sides intersect said central axis.

7. A thermal head according to claim 5, wherein the other ends of said second sides are connected to the ends of a third side, respectively.

8. A thermal head according to claim 7, wherein said second side is parallel to said first direction.

9. A thermal head according to any of claims 5 to 8, wherein said first boundary comprises first sides extending in a second direction, each of said first sides having two ends connected to said second side and to a respective one of said second boundaries.

10. A printing apparatus comprising the thermal head according to any one of claims 1 to 9, and a pressing mechanism for conveying and pressing a printing medium together with the thermal head.