JPS6113028A - Platen coupler in recording device - Google Patents

Abstract

PURPOSE:To make a coupling job ever so easy, besides simplication in structure, by installing a bar projection part in the radial direction of a platen driving shaft while a concave part in a platen knob respectively, and making a form of this concave part adjust to the bar projection part, in case of a platen coupler. CONSTITUTION:Two parallel pins 101 are installed in a platen shaft 2 in a diametral direction of this shaft, while a concave part 102, receiving the parallel pin 101 of the platen shaft 2, is installed in a coupling part of a plastic platen knob 3. An inlet part A of this concave part 102 is larger in width than a diameter of the parallel pin but an inlet part B is smaller and a C part is almost identical. Therefore, a platen driving shaft and the platen knob are easily coupled together, thus they are lockable with certainty.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a platen coupling device in a recording apparatus in which a platen knob is fitted and coupled to a platen drive shaft.

[Prior Art] FIG. 1 is a partially omitted plan sectional view of a recording apparatus. In the figure, a platen 1 is fixed to a drive shaft 2, and a platen knob 3 is fixed to one end of the drive shaft 2.

The drive shaft 2 is rotated by a motor (not shown), and performs operations such as changing the recording performed by the recording head 4 or conveying paper for setting paper.

On the other hand, when the platen 1 is manually rotated, the platen knob 3 is rotated by hand. At this time, the rotation of the platen 1 is not in a no-load state because a pinch roller, a drive belt system, etc. (not shown) operate in conjunction with the rotation. Therefore, the platen knob 3 is
must be fixed in the axial direction.

Of course, this situation applies not only between the platen and the platen knob, but also between other drive shafts and fixing members such as knobs and gears fixed to the drive shafts.

FIGS. 2 to 4 show examples of conventional coupling between a platen shaft and a platen knob.

In the conventional example shown in FIG. 2, a platen knob 3 for plastic acid is provided with a connecting portion 5, and the connecting portion 5 has a hole 6 having approximately the same shape as the cross section of the platen shaft and a fixing screw (not shown). A metal screw portion 7 into which the receiver is inserted is provided. This method involves tightening and fixing the platen shaft 2 with a fixing screw, but it requires a tool to attach and detach the platen knob 3, and has the disadvantage that it cannot be easily attached or removed. Furthermore, when manufacturing the platen knob 3, the plastic connecting part 5 and the metal threaded part 7 are
It also has the disadvantage that the process of forming both at the same time is complicated.

In the conventional example shown in FIG. 3, one end of the platen shaft 2 is
The hole 6 of the coupling part 5 is also formed into a D shape according to the milling process. The D-shape provides sufficient fixation in the direction of rotation. However, when installing the platen knob 3 by pushing it into the platen shaft 2, there are two drawbacks: it is not possible to judge how far it is pushed in and the manufacturing process is complicated because the platen shaft 2 must be milled. have.

In the conventional example shown in FIG.
is fixed, and two connecting rods 8 each having an arrow-shaped tip are fixed to the connecting portion 5 of the platen knob 3 so as to be in a positional relationship at both ends of the diameter. When bonding, two bonds s8
is inserted into the opening 9 provided in the coupling part 7, and the opening 9
The neck is hooked onto the connecting rod 8 on the back side of the neck and fixed.

In this method, the platen shaft 2 is sufficiently fixed in the axial and rotational directions, and by hooking the neck of the connecting rod 8 to the back side of the connecting part 7, a clicking sensation is produced when the platen knob 3 is attached, which is easy. Complete installation is possible. However, it is necessary to provide a special connecting portion 7 on the platen shaft 2 and a connecting rod 8 having a special shape on the platen knob 3, which has the disadvantage that the manufacturing process is complicated.

[Object of the Invention] The present invention has been made in view of the above-mentioned conventional problems, and
Its purpose is to provide sufficient axial and rotational fixation,
Another object of the present invention is to provide a platen coupling device for a recording device that has a simple structure and is easy to couple.

[Summary of the Invention] In order to achieve the objective, the platen coupling device in the recording device according to the present invention is provided with one or more bar-shaped protrusions in the radial direction of the platen drive shaft, and the platen knob is provided with the bar-shaped protrusions. The shape of the recess is narrower near the entrance than the width of the bar-shaped protrusion, the depth thereof has substantially the same shape as the cross-section of the bar-shaped protrusion, and It is characterized by a thin notch.

[Embodiments of the invention] Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 5 is a plan view of a first embodiment of a platen coupling device in a recording apparatus according to the present invention. In the figure, two parallel pins 101 are fixedly installed on the platen shaft 2 in the diametrical direction of the shaft. Further, the connecting portion 5 of the platen knob 3 made of an elastic material such as plastic is provided with a recess 102 into which the parallel pin 101 of the platen shaft 2 is received.

The recess 102 has the following shape. The width of the part A corresponding to the entrance is larger than the diameter of the parallel pin 101, and the part B
The width of the portion is smaller than the diameter of the parallel pin 1o1, the C portion has substantially the same shape and the same diameter as the parallel pin 101, and the D portion has a width sufficiently smaller than the diameter of the parallel pin 101. Each of the above parts is connected by a smooth curve.
It forms two recesses.

To attach the platen knob 3 to the platen shaft 2, insert the recess 102 of the platen knob 3 into the parallel pin 101 of the platen shaft 2.
Push it in the direction of arrow E. Then, the parallel bottle 101 passes through the A section of the recess 102 and reaches the B section. Since the B portion is narrower than the parallel pin 101, the elastic joint 5 is slightly expanded, and the parallel pin 101 is narrower than the parallel pin 101.
reach the part. Since the C portion has almost the same shape as the parallel pin 101, and the D portion has a sufficiently thin cut, the parallel pin 101 is stably fixed at the C portion. Therefore, the platen knob 3 is fixed in the rotational direction by the parallel pin 101 being fitted into the recess 102, and also fixed in the axial direction by the parallel pin 101 being sandwiched between the B portion and the D portion of the recess 102. .

Further, when the parallel pin 101 passes through the B portion of the recess 102, there is a feeling of resistance, and since the parallel pin 101 passes through the B portion and reaches the C portion, completion of the connection can be sensed. Further, the resistance force when passing through the B portion can be appropriately set depending on the length of the D portion.

Conversely, by pulling the platen knob 3 in the direction of arrow F, the parallel pin 101 can pass through the B portion of the recess 102 and be separated from the platen shaft 2.

FIG. 6 is a perspective view of a second embodiment of the invention.

In this embodiment, a gear 103 is attached to one end of the platen shaft 2. Gear 103 is connected to platen shaft 2
A mounting portion 104 for fixing the device has a fixing screw 105. Therefore, the fixing screw 105 can be used in the same way as the parallel pin 101 in the first embodiment.

That is, the hole 6 provided in the coupling part 5 of the platen knob 3 is fitted into the mounting part 104, and the fixing screw 105 is pushed into the recess 102 in the same manner as in the first embodiment. By using the fixing screw 105 in this way, the step of providing the parallel pin 101 on the platen shaft 2 can be omitted, and the structure can be simplified.

Although the case where the platen shaft 2 and the platen knob 3 are coupled has been described so far, the present invention is not limited to this. As shown in FIG. 7, a parallel pin lot is attached to the rotating shaft 106 in the same manner as in the first embodiment.
By providing a connecting portion 5 similar to that in the first embodiment to a fixing member to be coupled to the rotating shaft, such as the gear 107, any fixed member can be reliably and easily coupled to the rotating shaft.

[Effects of the Invention] As described above in detail, the platen coupling device in the recording apparatus according to the present invention can easily couple the platen drive shaft and the platen knob and securely fix them.

Furthermore, since the platen drive shaft is only provided with a bar-shaped protrusion and the platen knob is provided with a recess, the structure is simple and the manufacturing process can be simplified.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway plan view of a recording device; FIG. 2 is a partially cutaway plan view showing a first example of a conventional coupling device; and FIG. 3 is a partially cutaway plan view of a conventional coupling device. FIG. 4 is a perspective view showing a third example of a conventional coupling device; FIG. 5 is a plan view showing a first embodiment of a coupling device according to the present invention; and FIG. 6 is a second embodiment of a coupling device according to the present invention. Perspective view showing an example FIG. 7 is a perspective view showing a third embodiment of the coupling device according to the invention. 2φ: platen shaft, 3: platen knob. 5...Joining part, 101...◆Parallel bin, 102-...
Recess Figure 1 Figure 4 Figure 7

Claims (1)

[Claims] (1) In a platen coupling device for a recording device having a platen drive shaft and a platen knob fitted and coupled to the platen drive shaft, one or more rod-shaped protrusions are provided in the radial direction of the platen drive shaft. In addition, the platen knob is provided with a recess into which the bar-shaped protrusion is removably fitted, and the shape of the recess is narrower near the entrance than the width of the bar-shaped protrusion, and the depth thereof is substantially the same as the cross section of the bar-shaped protrusion. What is claimed is: 1. A platen coupling device for a recording device, characterized in that the platen coupling device has a shape with a thin notch at the back thereof.