JPH0751329Y2 - Thermal head displacement device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a thermal head displacement device that can be used in a facsimile machine or the like having a thermal head facing a print roller.

[Prior art and problems]

Generally, in a facsimile apparatus or the like in which a print roller and a thermal head are opposed to each other and a recording sheet is interposed between them to perform thermal recording, the print roller and the thermal head are temporarily separated from each other when the recording sheet is loaded, and recording is performed between them. Need to pass the paper.

For this reason, conventionally, one end of a support mechanism that supports the print roller or the thermal head is supported by a rotatable hinge portion, and a set position where the print roller and the thermal head are in pressure contact with each other by the operating mechanism and a release position where they are separated from each other. Was moved to (for example, Shokai 62-17816
(See Gazette No. 4).

However, in such a conventional configuration, misalignment between the print roller and the thermal head is likely to occur due to long-term use, which may deteriorate the print quality, and the structure around the thermal head becomes complicated, resulting in component arrangement. There is a problem that a facsimile or the like having a limited installation space is significantly disadvantageous in terms of cost reduction and downsizing.

An object of the present invention is to provide a thermal head displacement device that solves the above-mentioned problems existing in the prior art.

[Means for Solving the Problems]

The thermal head displacement device 1 according to the present invention comprises a support member 3 for supporting the thermal head 4.
By inserting projecting pieces 19, 20, 21 provided in the tangential direction in which the thermal head 4 and the printing roller 2 are in contact with each other from the end sides of the supporting holes 22, 23, 24 provided in the chassis 15, the supporting holes are formed.
By mounting the thermal head 4 so that it can be moved forward or backward with respect to the print roller 2 with 22, 23, and 24 as fulcrums, and by engaging the support member 3 with the bearing portions 7 of the print roller 2, Regulators 8, 8 whose position is regulated in the tangential direction
And the support member 3 is provided with springs 25, 26.
Is urged toward the print roller 2 side, and further, the engaged portion 5 is provided on the support member 3 and at least the thermal head 4 is displaced backward by engaging with and displacing the engaged portion 5. Operation lever 6s having an engaging portion 6a
Is provided.

In this case, the chassis 15 is provided with three support holes 22, 23, 24 located at the center and both sides thereof, and the support member 3
The three protruding pieces 19, 2 to be inserted into the respective support holes 22, 23, 24.
0, 21 are provided, the central projection piece 20 is always locked in the support hole 23, and the remaining projection pieces 19, 21 are attached to the support holes 22, 24 so that displacement in the front-back direction is allowed, Both sides of the support member 2 are biased by a pair of springs 25 and 26.
Further, the operation lever 6s is projected from the outer case 71.

[Action]

According to the displacement device 1 of the thermal head according to the present invention, the displacement of the operation lever 6s also displaces the engaged portion 5 that engages with the engagement portion 6a of the operation lever 6s. As a result, the engaged portion 5
The support member 3 integrated with the thermal head 4 is also displaced, and the thermal head 4 is displaced forward or backward with respect to the print roller 2. In this case, when the engaging portion 6a is separated from the engaged portion 5, the thermal head 4 is pressed against the print roller 2 by the urging support member 3, and the engaging portion 6a is engaged with the engaged portion 5. Then, if the engaged portion 5 is displaced against the biasing force, the thermal head 4 can be separated from the printing roller 2.

Further, in the structure for rotatably supporting the supporting member 3, the chassis 15 is provided with the projecting pieces 19, 20, 21 provided in the tangential direction in which the thermal head 4 and the printing roller 2 are in contact with each other from the end side of the supporting member 3. Since the thermal head 4 is configured only by being inserted into the support holes 22, 23, 24, the thermal head 4 can be moved forward or backward with respect to the print roller 2 with the support holes 22, 23, 24 as a fulcrum, and further, By simplifying the structure, cost reduction and size reduction can be achieved. In this case, the thermal head 4 is provided with the regulating portion 8 provided on the support member 3,
Since 8 engages with the bearings 7, 7 of the print roller 2, the position is regulated in the tangential direction.

Furthermore, the chassis 15 is provided with three support holes 22, 23, 24 located at the center and both sides thereof, and the support member 3 is provided with three projecting pieces 19, which are inserted into the support holes 22, 23, 24, respectively.
20 and 21 are provided, the central projection piece 20 is always locked in the support hole 23, and the remaining projection pieces 19 and 21 are attached to the support holes 22 and 24 so that displacement in the front-rear direction is allowed, Since both sides of the support member 2 are biased by the pair of springs 25 and 26, mechanical errors existing between the thermal head 4 and the print roller 2 are absorbed, and the entire surface of the thermal head 4 is evenly distributed on the print roller 2 side ( Contact). Therefore, good printing quality can be maintained in combination with the accurate and easy positioning action of the restriction portions 8 provided on the support member 3.

On the other hand, since the operation lever 6s is projected from the outer case 71, the thermal head 4 can be displaced by an easy manual operation without opening a cover or the like.

〔Example〕

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

First, in order to clarify the present invention, a schematic configuration of a facsimile apparatus incorporating the thermal head displacement device 1 will be described with reference to FIG.

The figure shows a schematic side view of a vertical section of the facsimile device 70. The facsimile device 70 includes an outer case 71, and a front surface 71a thereof.
A tray 72 for setting transmission originals is provided therein, and a transmission system such as a paper feeding mechanism 73 and a reading mechanism 74 is provided inside the tray 72.

On the other hand, in the receiving system, recording paper (roll paper) is placed inside an openable / closable cover 75 provided on the upper surface 71b of the outer case 71.
78 is stored. Further, the print roller 2 is disposed in front of the recording paper 78, and the thermal head 4 for recording is disposed in front of the print roller 2 so as to face the thermal head 4. The thermal head 4 is provided with the displacement device 1 according to the present invention. Supported. Therefore, when replacing the recording paper 78, the cover 75 is opened to store the new recording paper, and the thermal head 4 is retracted from the print roller 2 to form a gap between the two, and the recording paper is loaded through this gap. I do.

Next, regarding the configuration of the thermal head displacement device 1,
This will be described with reference to FIGS.

First, the print roller 2 is provided with a shaft portion 12 at the shaft center.
Is rotatably supported by bearings 7, 7 provided on left and right brackets 16a, 16b fixed to the chassis 15. The rotation of the shaft portion 12 is controlled by a driving portion 17 having a motor, a gear mechanism and the like.

On the other hand, the thermal head 4 is attached to the rectangular support plate 18 forming the support member 3 and is arranged in front of the print roller 2. Projecting pieces 19, 20, 21 are integrally provided on the lower side of the support plate 18 at the center, rightward and leftward, respectively, and a rectangular supporting hole 22 into which the projecting pieces 19, 20, 21 can be inserted in the chassis 15 with play. , 23, 24 are provided correspondingly (see FIG. 5). By selecting the shape of each of the support holes 22, 23, 24, the support plate 18 is allowed to be displaced in the vertical direction and stands up on the chassis 15, and the central protruding piece 19 is always locked to the support hole 22, The remaining protrusion pieces 20 and 21 are allowed to be displaced in the front-rear direction. Therefore, the support plate 18 can be pivotally displaced in the front-rear direction about the center as a fulcrum, and the thermal head 4 can be uniformly pressed against the print roller 2.

A pair of left and right springs 25 and 26 are provided between the chassis 15 and the support plate 18 so as to urge the thermal head 4 to press against the peripheral surface of the print roller 2.

Further, the left and right ends of the support plate 18 are bent at a right angle toward the print roller 2 side as shown in FIG. 6, and the regulating portions 8 are integrally provided. The regulation portion 8 has a pair of regulation pieces 8a and 8b which are vertically spaced apart from each other, and the bearing portion 7 is inserted between the regulation pieces 8a and 8b. Therefore, the regulating portion 8 is regulated by the bearing portion 7 in the vertical direction, that is, in the tangential direction in which the print roller 2 and the thermal head 4 contact each other, so that the thermal head 4 is accurately positioned with respect to the print roller 2. The restriction portion 8 is allowed to be displaced in the front-rear direction (advancing / retracting direction) with respect to the bearing portion 7.

On the other hand, the support plate 18 is provided with the engaged portion 5. The engaged portion 5 has a parallel engaged piece 5a which is separated from the support plate 18 by a predetermined width. On the other hand, the lower end of the operation lever 6s is attached to the chassis 15 by the support shaft 11 so as to be rotatable and displaceable in the left-right direction. A knob 6c that can be manually operated is provided on the upper end of the operation lever 6s, and the knob 6c projects upward from the outer case 71 as shown in FIG. Further, an engaging portion 6a having an inclined portion 9 is integrally provided at an intermediate position of the operation lever 6s. The engaging portion 6a is arranged next to the engaged piece 5a as shown in FIG. 3, and if the operating lever 6s is displaced to the engaged piece 5a side, the engaged piece 5a that comes into contact with the inclined portion 9a. Are displaced in a direction substantially perpendicular to the displacement direction of the operation lever 6s. In addition,
A detection piece 6b is integrally provided on the operation lever 6s, and its position, that is, the position of the operation lever 6s can be detected by the sensor unit 28.

Next, the function of the supporting device 1 will be described.

First, during normal use, the operating lever 6s is positioned at the set position P1 shown by the solid line in FIGS. 2 and 3. As a result, the contact between the inclined portion 9 and the engaged piece 5a is released, and the support plate 18 is biased by the springs 25 and 26, so that the thermal head 4 comes into pressure contact with the print roller 2 (recording paper). At this time, since the restricting portions 8 and 8 are positionally regulated in the tangential direction with respect to the thermal head 4, the restricting portions 8 and 8 are accurately positioned, and the protrusions 19, 20 and 21 and the support holes 22, 23 and 24 prevent the forward and backward movement. Since the displacement is allowed, the thermal head 4 uniformly presses the print roller 2.

On the other hand, when the recording sheet is not used for replacement, the operation lever 6s is operated to displace it to the release position P2 shown by the phantom line in FIGS. 2 and 3. As a result, since the inclined portion 9 displaces the engaged piece 5a, the support plate 18 tilts with the protruding piece 19 as a fulcrum, the thermal head 4 retracts from the print roller 2, and the two are separated. Therefore, the recording paper can be loaded between the thermal head 4 and the print roller 2.

Although the embodiments have been described in detail above, the present invention is not limited to such embodiments. For example, the displacement direction of the operation lever and the displacement direction of the engaged portion may be the same direction. Further, the support member and the restriction portion can be implemented by other configurations or shapes having the same function. Furthermore, although the facsimile machine is exemplified, it can be applied to any other equipment having a thermal head.

[Effect of device]

As described above, the thermal head displacement device according to the present invention includes the support member for supporting the thermal head, and the projection piece provided on the chassis in the tangential direction where the thermal head and the print roller are in contact with each other from the edge of the support member. By inserting the thermal head so that it can be moved forward or backward with respect to the print roller by using the support hole as a fulcrum by inserting it into the provided support hole, and by engaging the support member with the bearing portion of the print roller, A restricting portion whose position is regulated in the tangential direction is provided, the supporting member is urged toward the print roller by a spring, and an engaged portion is provided on the supporting member and engages with the engaged portion. In addition, since the operation lever having the engaging portion that at least retracts and displaces the thermal head by displacing it is provided, the thermal head support structure is Etc. is simplified Te because, by simplifying the structure around the thermal head, thereby the cost and size.

Further, the chassis is provided with three support holes located at the center and both sides thereof, and the support member is provided with three projecting pieces to be inserted into the respective support holes, and the central projecting piece is always locked in the support hole, The remaining protrusions were attached to the support hole so that displacement in the front-rear direction was allowed, and both sides of the support member were urged by a pair of springs, so the mechanical force present between the thermal head and the print roller was increased. Error can be absorbed and the entire surface of the thermal head can be brought into contact with the printing roller side uniformly (equal pressure), and in addition,
Good printing quality can be maintained in combination with the accurate and easy positioning action of the restriction portion provided on the support member.

Furthermore, by projecting the operation lever from the outer case, the thermal head can be displaced by an easy manual operation without opening a cover or the like.

[Brief description of drawings]

1 is a plan view of a displacement device according to the present invention, FIG. 2 is a front view of the displacement device, FIG. 3 is a plan view showing a displacement state of an operating lever in the displacement device, and FIG. 4 is a displacement device. 5 is a left side sectional view showing a displacement state of the thermal head in FIG. 5, FIG. 5: a bottom view showing a projection piece and a support hole of a supporting member in the displacement device, and FIG. 6: a side view clearly showing a restricting portion in the displacement device. FIG. 7: A schematic vertical sectional side view of a facsimile machine incorporating the displacement device. In the drawings, 1: thermal head displacement device, 2: printing roller 3: support member, 4: thermal head 5: engaged part, 6s: operating lever 6a: engaging part, 7, 7: bearing part 8, 8: Regulator, 15: Chassis 19, 20, 21: Projection piece, 22, 23, 24: Support hole 25, 26: Spring, 71: External case

Claims (1)

[Scope of utility model registration request] 1. A thermal head displacement device for displacing a thermal head forward or backward with respect to an opposing print roller, comprising a support member for supporting the thermal head, and the thermal head and the print roller from the edge of the support member. By inserting the three protrusions located in the center of the tangential direction and on both sides thereof into the three support holes provided in the center of the chassis and on both sides thereof, the center protrusion is always engaged with the support hole. The thermal head is mounted so as to be able to move forward or backward with respect to the print roller so that the remaining projection pieces can be displaced in the front-back direction with respect to the support hole, and the bearing portion of the print roller is attached to the support member. By providing a regulating portion for regulating the position in the tangential direction by engaging with, the both sides of the supporting member are connected to the printing roller side by a pair of springs. Urges, further, provided with a engaged portion to the support member engages the engaged portion,
Further, a displacement device for a thermal head, characterized in that an operating lever having an engaging portion for moving the thermal head backward at least by displacement is provided.