JP3097427B2 - Head mounting structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting structure for a printing or reading head provided in, for example, a thermal recording type facsimile apparatus.

[0002]

2. Description of the Related Art Generally, in a facsimile apparatus of this type, a platen roller is arranged so as to extend in the width direction of a sheet, and a thermal head also extends in the direction of the sheet so as to face the platen roller. Are arranged as follows. The paper is fed by the rotation of the platen roller, and printing is performed on the paper by the thermal head in a state where the paper is supported on the platen roller.

Conventionally, as a mounting structure of a thermal head, for example, a technique as shown in FIG. 5 is known. As shown in the figure, a platen roller 52 is supported on the main frame 51 so as to be able to rotate positively. On the main frame 51, a cover frame 53 is provided so as to be openable and closable so as to cover the same frame 51. The head bracket 5 is provided on the lower surface of the cover frame 53.
A thermal head 55 is mounted on the lower surface of the head bracket 54 so as to be vertically movable. The upper surface of the head bracket 54 is urged toward the platen roller 52 by a leaf spring 56, so that the recording paper P is securely brought into close contact with the thermal head 55.

[0004]

However, in the facsimile apparatus, the plate spring 56 for improving the degree of adhesion between the thermal head 55 and the recording paper P is provided by the platen roller 52.
Are arranged so as to extend in a direction orthogonal to the axial direction. Since the leaf spring 56 needs to have a certain degree of elasticity, its total length must be relatively long. Therefore, a considerable space for mounting a leaf spring is required in a direction perpendicular to the axial direction of the platen roller 52, that is, in the feeding direction of the recording paper P, and there is a problem that the facsimile apparatus becomes large.

The present invention was made to solve the above problems, and an object while ensuring the elastic force of the leaf spring, even different paper sizes, the miniaturization of the frame
Figure Rukoto and also used as is to provide a mounting structure of a head capable.

[0006]

In order to achieve the above object, according to the present invention, there is provided a head mounting structure in which a printing or reading head urged toward a platen roller by a plate spring is provided on a frame . line connecting both ends of the plate spring, so as to extend in the axial direction in the same direction of the platen roller
Only set the leaf spring, in accordance with the mounting position of the leaf spring to the paper size
The gist is that it can be changed .

[0007]

SUMMARY OF] According to the arrangement, the length required for leaf spring definitive in a direction perpendicular to the axial direction of the platen roller becomes possible to significantly shorter than conventional. Also, paper size
It is possible to change the mounting position of the leaf spring according to
You.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied in a facsimile machine will be described below with reference to the drawings.

[0009] As shown in FIG. 1, the upper portion of the main frame 1 is openably supported by a shaft which top frame 2 made of metal is not shown. A metal plate 1a is mounted on the lower surface of the main frame 1. A panel 3 made of synthetic resin is mounted on the upper surface of the top frame 2. Therefore, the panel 3 and the top frame 2 are integrally opened and closed with respect to the main frame 1. In this embodiment, the top frame 2 forms a frame .

At a substantially central portion of the main frame 1, a recording paper storage chamber 5 for storing a recording paper P in a roll form is formed. At the rear of the main frame 1, a document insertion slot 6 is provided.
Are formed. A document separation unit 7 is provided downstream of the document insertion port 6. The document separation unit 7 includes a separation roller 8 supported by the main frame 1 so as to be able to rotate positively, and a separation pad 9 forcibly contacting the outer peripheral surface of the separation roller 8 by the urging force of the pusher 14. Then, the original G is set to 1 by the separation roller 8 and the separation pad 9.
The sheet is separated one by one, and is rolled between the main frame 1 and the top frame 2.

A reading unit 10 is provided at the position of the main frame 1 downstream from the contact portion between the separation roller 8 and the separation pad 9. The reading unit 10 includes a contact-type image sensor 11, a platen roller 12, which is rotatably supported on the back surface of the top frame 2, and is in contact with the image sensor 11. A document conveying path 13 is formed downstream of a contact portion between the image sensor 11 and the platen roller 12. A document discharge port 49 for discharging a document whose image data has been completely read by the image sensor 11 is formed downstream of the document conveyance path 13.

At the front of the panel 3, there are provided basic function keys 20, such as keys operated when starting transmission of a document. A plurality of call function keys 21 such as a numeric keypad are provided at substantially the center of the panel 3. A liquid crystal display panel 22 for displaying a dial number or the like is provided at the position of the panel 3 at the rear of the call function key 21. A cover 25 is disposed on the upper surface of the panel 3, and the cover 25 is supported on the panel 3 so as to be openable and closable and detachable. A key rubber 26 having a plurality of keys 27 is mounted on the cover 25. By pressing the key 27 of the key rubber 26 when the cover 25 is closed,
The call function key 21 of the panel 3 below the cover 25 can be pressed. In addition, behind the key rubber 26, a window 2 through which the liquid crystal display panel 22 is exposed when the cover 25 is closed.
An opening 8 is formed. When the cover 25 is opened (shown by a two-dot chain line in FIG. 1), the cover 25 serves as a tray on which the document G is placed.

A recording section 30 is provided at the front of the main frame 1 and the top frame 2. A paper guide 32 for guiding the recording paper P to the cutter 31 is arranged on the main frame 1 on the downstream side of the recording unit 30. At the front of the main frame 1 and the panel 3, a recording paper discharge port 33 for discharging the recording paper P passing through the recording section 30 is formed.

Next, the recording section 30 will be described in detail.
As shown in FIGS. 1 and 2, the main frame 1 supports a platen roller 34 extending in a direction orthogonal to the paper feeding direction so as to be able to rotate positively. A thermal head 35 extending in the same direction as the platen roller 34 is in opposition to the upper portion of the platen roller 34. The thermal head 35 is fixedly supported by a head bracket 37 via an aluminum heat dissipation plate 36 having a similar shape to a plane. As shown in FIG. 3 and FIG.
Thus , the heat radiating plate 36 is fixed to the head bracket 3 by the screw 50.
7. A clearance is provided between the heat radiating plate 36 and the head bracket 37 in consideration of the difference in the coefficient of thermal expansion between the heat radiating plate 36 and the head bracket 37.

Engaging claws 38 are formed on both front and rear edges of the head bracket 37, respectively. Double engaging claw 3
Reference numerals 8 are respectively engaged with engagement holes 39 formed in the top frame 2. The size of the engaging hole 39 of the top frame 2 is larger than the thickness of the engaging claw 38 of the head bracket 37, and the head bracket 37 is allowed to move vertically with respect to the top frame 2. It is in.

As shown in FIGS. 3 and 4, a first leaf spring mounting portion 40a and a second leaf spring mounting portion 40b are formed in the top frame 2 so as to bulge in the width direction. The first leaf spring mounting portion 40a is a second leaf spring mounting portion 40b.
4 are formed longer than in the left-right direction of FIG. 4, and two screw holes 41 and 41a are formed on both sides thereof. A pair of bosses 42, 42a are provided on both sides of each screw hole 41, 41a.
Are formed to protrude. On the other hand, the second leaf spring mounting portion 40
One screw hole 41 is formed at the center of b, and a pair of bosses 42 are formed on both sides thereof.

The leaf spring 43 has a rectangular plate shape that is long in the left-right direction, and both ends thereof are bent downward. The leaf spring 43 has a screw insertion hole 44 formed at the center thereof, and a pair of boss holes 4 on both sides of the screw insertion hole 44.
5 are formed. The boss holes 45 of the leaf spring 43 are engaged with the bosses 42 of the leaf spring mounting portions 40a and 40b. A screw 46 is inserted into a screw insertion hole 44 of the leaf spring 43, and the screw 46 is attached to the leaf spring mounting portions 40a, 40a.
B is screwed into the screw hole 41. That is, the leaf spring 4
Numeral 3 is non-rotatably mounted and fixed to the leaf spring mounting portions 40a and 40b. As shown in FIG. 4, through hole 3 at both ends of the plate spring 43 which are opened in the head bracket 37
It contacts the heat radiating plate 36 through 7a. This leaf spring 4
Due to the elastic force of 3, the head bracket 37 is always pressed downward, that is, toward the platen roller 34, and the thermal head 35 is securely brought into close contact with the platen roller 34. That is, the recording paper P is securely brought into close contact with the thermal head 35.

In this embodiment, the recording paper P of B4 size is used.
4A, the thermal head 35 is urged toward the platen roller 34 by using two leaf springs 43, as shown in FIG. 4A. When this is embodied in a facsimile apparatus using A4 size recording paper P, as shown in FIG. 4B, a long leaf spring 43 is attached to the first leaf spring mounting portion 40a.
Then, the thermal head 35 is urged toward the platen roller 34 with the sheets fixed. That is, the top frame 2 of the present embodiment
Can be used for both types of facsimile apparatuses using B4 size recording paper P and facsimile apparatuses using A4 size recording paper P.

In the case shown in FIG. 4A, the mounting position of the leaf spring 43 is set so as to be symmetrical with respect to the center of the B4 size recording paper. In the case shown in FIG. A leaf spring 43 is provided at the center of an A4 size recording sheet which is fed to one side of the apparatus. For this reason, a screw hole 41a dedicated to A4 and a boss 42a are provided at a position different from the screw hole 41 in the first leaf spring mounting portion 40a.

As described above, in this embodiment, the plate spring 43 for pressing the thermal head 35 toward the platen roller 34 is used.
The leaf spring 43 is fixed to the top frame 2 so that both ends of the plate spring 43 extend in the same direction as the axial direction of the platen roller. As a result, the lengths of the main frame 1 and the top frame 2 in the recording paper feed direction can be significantly reduced as compared with the related art. As a result, the size of the facsimile apparatus can be reduced while securing the elastic force of the leaf spring 43.

It should be noted that the present invention is not limited to the above-described embodiment, and may be configured as follows, for example, without departing from the spirit of the invention. (1) The present invention is embodied in a reading device other than a facsimile machine, such as a copying machine.

(2) The present invention is embodied with a head for reading image data of a document, that is, an image sensor 11 mounting structure. (3) The shape of the leaf spring 43 is appropriately changed. For example,
A leaf spring that presses the heat radiating plate 36 only at one end is used.

(4) The number of leaf springs 43 to be used is appropriately changed. For example, as shown in FIG. 4B, the present invention can be embodied in a facsimile apparatus using A4 size recording paper P using one leaf spring 43 longer than the leaf spring 43 used in the above embodiment.

[0024]

As described in detail above, according to the present invention,
While ensuring the elastic force of the leaf spring, there in different paper sizes
Even it demonstrates an excellent effect of the combined and downsizing of the frame may FIG Rukoto.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a facsimile apparatus showing an embodiment embodying the present invention.

FIG. 2 is a partial cross-sectional view of a facsimile apparatus showing a configuration of a recording unit.

FIG. 3 is a perspective view of a facsimile apparatus showing a configuration of a recording unit.

FIG. 4A is a front view of a recording unit of a facsimile apparatus using B4 size recording paper. FIG. 2B is a front view of a recording unit of the facsimile apparatus using A4 size recording paper.

FIG. 5 is a partial side sectional view of a facsimile apparatus showing a conventional leaf spring mounting structure.

[Description of Signs] 2 ... Top frame as frame, 11 ... for reading
Image sensor as head, 12 ... Platen low
La, 34 ... platen roller, 35 ... thermal head as a head for printing, 43 ... plate spring.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-221647 (JP, A) JP-A-3-55273 (JP, A) JP-A-4-232082 (JP, A) JP-A-5-205 236195 (JP, A) JP-A 4-64147 (JP, U) JP-A 6-64896 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41J 25/34 B41J 2 / 32 H04N 1/032

Claims (1)

(57) [Claims] 1. A head provided on a frame for printing or reading which is urged toward a platen roller by a leaf spring.
In the mounting structure of the door, a line connecting both ends of the leaf spring is
The plate bar extends in the same direction as the axial direction of the platen roller.
And change the mounting position of the leaf spring according to the paper size.
Possible and to mounting structure of the head, characterized in that the.