JPH0832450B2 - Press holding device for information recording means - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a pressure holding device for information recording means, and more specifically, it holds information recording means such as a thermal head against a platen roller. The present invention relates to a pressure holding device for information recording means.

(Prior Art) Conventionally, when a thermal head unit incorporating a thermal head is arranged in a state in which information can be recorded on a recording medium such as a thermal paper carried by a platen roller, the following is described. Adjustments are being made.

That is, first, in order to align the heat generating part of the thermal head with the platen roller, an adhesive tape is attached to the heat generating part of the thermal head, and the exposed surface of this adhesive tape is coated with ink to platen this part. Contact the roller. Then, the platen roller is rotated to check the ink removal state on the adhesive tape surface, and to check the positional deviation of the heat generating portion with respect to the platen roller.

Also, in order to prevent the thermal head from hitting the platen roller in one-sided contact, the position of the thermal head unit should be adjusted so that the head surface of this thermal head and the outer peripheral surface along the rotation axis of the platen roller are parallel. The thickness gauge is sandwiched between the thermal head mounting portions of the thermal head unit for fine adjustment.

(Problems to be Solved by the Invention) As described above, in the conventional thermal head unit, the assembly adjustment is complicated and requires a lot of time, and if the assembly adjustment is not strictly performed, the thermal head and the platen roller are not combined. There is a problem that stable information recording cannot be performed due to the positional deviation.

Therefore, it is an object of the present invention to provide a pressing and holding device for information recording means, which is simple in assembly and adjustment and can contribute to stable information recording.

[Configuration of the Invention] (Means for Solving the Problems) The present invention includes a platen roller having elasticity and carrying a recording medium, and an information recording means for recording information on the recording medium carried by the platen roller. A press-holding device for the information recording means that press-holds the information recording means on the platen roller, wherein a support shaft body is disposed along the axial direction of the platen roller and at a predetermined distance from the platen roller. A support portion provided along the support shaft for supporting the information recording means, a central positioning piece provided at a central portion of the support portion and projecting toward the support shaft, and a support portion along the support shaft. Upper and lower positioning pieces that engage with the support shaft from two opposite directions on both sides of the central positioning piece. A support member which is engaged with the support shaft body in two directions in a loosely fitted state and rotatably supports the information recording means with respect to the support shaft body with the central positioning piece as a fulcrum; The information recording means supported by the support shaft via a support member is pressed to the platen roller side, and the information recording means is rotated in a direction in which the information recording means comes in contact with and separates from the platen roller with the central positioning piece as a fulcrum. A pressing restraint mechanism portion for restraining is provided.

(Operation) The operation of the apparatus having the above configuration will be described below.

According to this device, the central positioning piece provided in the substantially central portion of the supporting member for supporting the information storage means in the joined state exerts a fulcrum action with the supporting shaft body, and is provided on both side portions of the supporting member. With the upper and lower positioning pieces engaged with the support shaft, the support member and the information recording means are pressed toward the platen roller by the press restraint mechanism. Then, the pressing restraint mechanism restrains the rotation moment about the supporting member and the central positioning piece of the information recording means as a fulcrum, so that the information recording means is always pressed by the platen roller in a stable state.

Further, the slight displacement of the information recording means with respect to the platen roller is absorbed by the elasticity of the platen roller.

(Example) Below, the Example of this invention is described in detail.

The embodiment pressure holding device 1 shown in FIGS. 1 to 3 has a structure in which a thermal head 2 as an information recording means is pressed against a platen roller 3 made of urethane rubber having a hardness of about 30 °.

The pressure holding device 1 includes a support shaft body 4 arranged along the axial direction of the platen roller 3 and at a predetermined distance from the platen roller 3, and the thermal head 2.
And a supporting member 5 for supporting the thermal head 2 and the supporting member 5 around the supporting shaft 4 to press the heat generating portion 2b of the thermal head 2 against the outer peripheral surface of the platen roller 3. In addition, the thermal head 2 has a pressing and restraining mechanism portion 6 that restrains a rotational moment in a direction in which the thermal head 2 approaches and separates from the platen roller 3.

The thermal head 2 is a rectangular parallelepiped head body 2a.
A plate-shaped heat generating portion 2b closely arranged along the upper side of one surface (front surface) of the head body 2, and the heat generating portion 2b arranged on the lower side of the one surface of the head body 2. The printed board 7 on which a wiring pattern for energizing is formed, the socket 8 for energizing the printed board 7, and the area from the open surface of the printed board 7 to the lower side of the heat generating part 2b. A thin plate-shaped guide piece 9 arranged,
A screw 10 which penetrates the guide piece 9 and the printed circuit board 7 and is screwed to the head body 2a to fix them to the head body 2a, and a protection piece fixed to the guide piece 9 below the screw 10. It has 11 and.

As shown in FIG. 1, the support shaft body 4 has a central groove 4a at a position corresponding to the central portion of the thermal head 2, and the head main body of the thermal head 2 around the central groove 4a.
Both side grooves 4b, 4c having a distance L larger than the length of 2a are provided respectively.

The support member 5 is a head body 2a of the thermal head 2.
A flat joint piece 5a having a length greater than the length of
Side pieces 5b, 5c protruding toward the support shaft 4 side from both sides of the joining piece 5a with a space L, and substantially semicircular vertical positioning pieces 12b, 12c respectively provided on the side pieces 5b, 5c. A central positioning piece 12a protruding from the central portion of the joining piece portion 5a toward the support shaft body 4 and a notch portion 13 for exposing the socket portion 8 provided in the lower central portion of the joining piece portion 5a. And the joining piece
The stopper piece 14 is provided so as to project obliquely upward from the upper end of the center of 5a.

Then, as shown in FIG. 1, the fixing screw 15 is screwed into the head main body 2a by penetrating the joining piece portion 5a so that the thermal head 2 is positioned between the platen roller 3 and the support shaft body 4. While being supported in a state of being joined to the head main body 2a, the central positioning piece 12a is engaged with the central groove 4a of the support shaft body 4, and the vertical positioning pieces 12b, 12
c is engaged with the both side grooves 4b, 4c in a loosely fitted state, whereby the thermal head 2 and the support member 5 are rotatable around the support shaft body 4, and the thermal head 2 and the support member 5 are also rotatable. Is supported rotatably in the longitudinal direction of the support shaft body 4 with the central positioning piece 12a as a fulcrum.

The pressing restraint mechanism portion 6 has one end portion hooked on the hooking recessed portions 5d, 5e provided at the lower end portions of the side piece portions 5b, 5c, and at the same time, as shown in FIG. Two tension springs 17 having the same elasticity with the other end hooked
Is provided. Then, as shown schematically in FIG. 4, the head main body 2a is in one-side contact with the platen roller 3, and the extension of one of the tension springs 17 (tensile force F ₁ ) is the extension of the other spring 17 (tensile force F ₁ ). ₂ ) When it becomes larger than F2, the state of F ₁ > F _{2 is established} , and the head body 2a is rotated in the direction of arrow α shown in FIG. 4 with the central positioning piece 12a as a fulcrum to return the half-contact state to the normal state. It has become. That is, the pressing restraint mechanism portion 6 restrains the rotational moment in the direction of coming in contact with and separating from the platen roller 3 with the central positioning piece 12a of the thermal head 2 and the supporting member 5 as a fulcrum.

The central positioning piece 12a is used for the thermal head 2
It also has a function of positioning the print area on the recording medium (for example, thermal paper) P.

Here, the jig 20 for attaching the thermal head 2 to the support member 5 will be described with reference to FIGS. 5 and 6.

The jig 20 has a flat plate-shaped jig base 21 having a length L ₁ which is larger than the distance L between the both side grooves 4b and 4c, and a lengthwise direction (X direction) on the jig base 21. First and second lift portions 22a, 22b arranged opposite to each other at the both ends, and two corner abutment pins protruding upward from the jig base 21 in the vicinity of the first lift 22a. 23a, 23b and the above 2
Of the abutting pin 23c which is projected in a linear positional relationship with the one corner abutting pin 23b in the vicinity of the lift portion 22b, and the length direction of the jig base 21 on the jig base 21. A pushing guide portion 24 having vertically arranged pushing pieces 24a, 24b slidably arranged in a direction orthogonal to each other (Y direction), and bottom portions on both sides of each of the first and second lift portions 22a, 22b. It has spacers 25a, 25b, 26a, 26b that are inserted through the jig base 21 and adjust the heights of the first and second lift portions 22a, 22b in the Z direction.

In the first lift portion 22a and the second lift portion 22b,
Engagement protrusions 22c, 22d having circular cross sections are provided so that the upper and lower positioning pieces 12b, 12c can engage with each other in a state of being opposed to each other. In addition, the first and second lift portions 22a and 22b are the jig base 21.
The spacers 25a, 25b are inserted in the bottom of the first lift portion 22a and the spacers 26a, 26b are inserted in the bottom of the second lift portion 22b. Causes the engaging protrusions 22c and 22d to move to the jig base 21.
It is configured to maintain a constant height from the upper surface of the.

When the thermal head 2 and the supporting member 5 are joined using this jig 20, first, the joining piece portion of the supporting member 5 is attached to the other surface of the head body 2a of the thermal head 2.
The support member 5 is temporarily fixed by the fixing screw 15 while closely adhering to 5a.

Next, as shown in FIG. 6, one corner of the head body 2a is abutted against the corner abutment pieces 23a, 23b, and the other portion of the head body 2a near the corner is abutted by the abutment pin. The upper and lower positioning pieces 12a, 12b of the support member 5 are engaged with the engaging projections 22c, 22d in the state of being brought into contact with the 23c. Further, in order to join the head body 2a and the joining piece portion 5a of the support member 5 in parallel, the pushing pieces 24a, 24b of the pushing guide portion 24 are provided.
The pressing guide portion 24 is slid in the Y direction while bringing the contact piece 5a into contact with the joining piece portion 5a. As a result, the joining piece portion 5a is in complete contact with the head body 2a and is in a parallel arrangement state. In this state, by tightening the fixing screw 15, the supporting member 5 can be attached to the head body 2a in a completely parallel state.

According to the pressure holding device 1 having the above-described configuration, the central positioning piece 12a provided in the substantially central portion of the support member 5 that supports the thermal head 2 in a joined state engages with the central groove 4a of the support shaft body 4 and acts as a fulcrum. And the upper and lower positioning pieces 12b, 12c provided on the support member 5 are provided on the support shaft body 4 on both side grooves 4b,
The heat generating portion 2b of the thermal head 2 is pressed against the outer peripheral surface side of the platen roller 3 by the two tension springs 17 in the state of being engaged with the 4c, whereby the heat generating portion 2b and the outer peripheral surface of the platen roller 3 are separated from each other. Information can be recorded on the recording medium P by the thermal head 2 while sandwiching the recording medium P therebetween.

Then, as described above, the rotational moment in the direction of contacting with and separating from the platen roller 3 with the central positioning piece 12a of the supporting member 5 and the thermal head 2 as the fulcrum causes the tensile forces F ₁ and F ₂ generated in the tension spring 17 to be generated. Therefore, the heat generating portion 2b of the thermal head 2 is always pressed in parallel with the platen roller 3 toward the platen roller 3 side, which causes the heat generating portion 2b to the recording medium P. It is possible to prevent displacement.

Further, the subtle displacement of the heat generating part 2b with respect to the platen roller 3 is caused by a nip due to the elastic deflection generated in the platen roller 3 (the platen roller 3 which is formed when the heat generating part 2b is pressed by the platen roller 3 has a recess in the outer peripheral portion) Be absorbed.

By the action of the pressure holding device 1 described above, the recording medium P
On the other hand, it is possible to perform stable information recording without positional deviation.

Further, if the thermal head 2 and the supporting member 5 are attached using a jig 20 as shown in FIG. 5, the thermal head 2 and the supporting member 5 can be completely parallel to each other by a simple operation. Can be installed on.

The present invention is not limited to the embodiment described above,
Various modifications are possible within the scope of the gist.

[Effects of the Invention] According to the present invention described in detail above, since the information recording means is rotatably held and pressed against the platen roller, the information recording means can always be pressed against the platen roller in a stable state. It is possible to provide the pressure holding device that can be assembled and whose assembly and adjustment are simplified.

[Brief description of drawings]

FIG. 1 is a perspective view showing a schematic configuration of an apparatus according to an embodiment of the present invention,
2 is a perspective view showing the apparatus viewed from a different angle from the case of FIG. 1, FIG. 3 is a schematic sectional view of the apparatus, and FIG. 4 shows an operation of a pressure restraint mechanism portion of the apparatus. Explanatory drawing, FIG. 5 is a perspective view showing a jig used for assembling the apparatus, and FIG. 6 is a plan view showing a mounting state of a thermal head and a supporting member using the jig shown in FIG. 1 ... Pressure holding device, 2 ... Thermal head, 3 ... Platen roller, 4 ... Support shaft, 5 ... Support member, 6 ...
... Pressure restraint mechanism section, 12a ... Center positioning piece, 12b, 12c ...
... Upper and lower positioning pieces.

Claims (1)

[Claims] 1. A platen roller having elasticity and carrying a recording medium, and information recording means for recording information on the recording medium carried by the platen roller, wherein the information recording means is pressed and held by the platen roller. In the pressure holding device of the information recording means, a support shaft body disposed along the axial direction of the platen roller and at a predetermined distance from the platen roller, and the support shaft body provided along the support shaft body. A supporting portion for supporting the means, a central positioning piece provided in the central portion of the supporting portion and projecting toward the supporting shaft, and both side portions of the central positioning piece along the supporting shaft with respect to the supporting shaft. And upper and lower positioning pieces that engage from opposite two directions,
The central positioning piece is engaged with the support shaft body, the upper and lower positioning pieces are engaged with the support shaft body in a loosely fitted state from two directions, and the central positioning piece is used as a fulcrum with respect to the support shaft body. And a supporting member for rotatably supporting the information recording means, the information recording means supported by the supporting shaft body via the supporting member, is pressed toward the platen roller side, and the central positioning piece is used as a fulcrum. A pressure holding mechanism for holding the rotation of the information recording means in the direction of coming in and out of contact with the platen roller.