JPH0448633B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a paper holding mechanism for a printer that makes it possible to automatically set a cut sheet or the like at a predetermined printing position.

<Conventional> Conventionally, there is a paper holding mechanism of this type as shown in FIG. 6, for example, and FIG. 6 will be described below. A paper feed roller 203 is in pressure contact with a rotatably supported platen 201 via a paper 202. The paper presser roller 208 is rotatably supported by a paper presser roller shaft 209 that is arranged parallel to the platen 201, and the paper presser roller shaft 209 has both ends rotatably supported around a fulcrum 210 on both sides of the printer. It is supported by a paper pressing roller 207. The paper presser roller 208 is connected to the paper presser lever 2 by paper presser springs 211 installed on both sides of the printer.
It is in pressure contact with the platen 201 via 07. If you want to automatically set the paper 202,
After the tip of the paper feed roller 203 and the platen 201 are set at the contact point between the paper feed roller 203 and the platen 201, the release solenoid 205 moves the paper presser lever 207 via the connecting lever 206 and the paper presser lever 206 so that the paper presser lever 207 does not interfere with the paper 202. position, rotate the platen 201 to send the leading edge of the paper 202 to the leading edge position 202-B, release the release solenoid 205, return the paper press lever 207 to the holding position 207-A, and press the paper 202.
202-A. When setting the paper 202 manually, the paper presser lever 207 is manually released to the release position 207-C. At this time, the protrusion 207-1 of the paper presser lever 207 is a plate spring with one end fixed.
The paper press lever 207 is held at the release position 207-C by the force of the spring that passes over the protrusion 212-1 of the lock spring 212. Furthermore, paper feed roller 2
Release 03 and release it from the platen 201,
After setting the paper 202 in a desired position, manually return the paper presser lever 207 to the presser position 207-A,
Release the release of the paper presser roller 203 and release the paper 2.
Set 02. In the above operation, when the paper presser lever 207 is released by the release solenoid 205 in the case of automatic paper setting, the protrusion 212-1 of the lock lever 212 is locked due to inertia.
Even if the protrusion 207-1 of the paper presser lever 207 climbs over the paper presser lever 207 and releases the release solenoid 205, the paper presser lever 207 will be held at the release position 207-C and there is a risk that it will not return to the presser position 207-A. However, it had the disadvantage of unstable operation. Furthermore, in order to avoid such malfunctions, it is necessary to increase the distance difference a between the release position 207-B of the paper presser lever 207 in automatic setting and the release position 207-C in manual setting. . However, it is often difficult to increase the release amount of the paper presser 207 due to interference between the print head 204 and the paper presser roller 208, and even if the release amount can be increased, the device becomes larger. It was hot.

<Purpose> The present invention aims to eliminate such drawbacks by providing a paper presser release lever that transmits driving force from the plunger to the paper presser lever, and when automatically setting paper, the paper presser release lever engages the lock lever with the paper presser lever. When the paper presser lever is pushed down to the release position and the plunger is released, the paper presser lever automatically returns to its original position, and when paper is manually set, the paper presser lever engages with the lock lever and is held at the release position. The purpose of the present invention is to provide a paper holding mechanism for a small printer that operates reliably and stably.

<Example> Examples of the present invention are shown in FIGS. 1, 2, and 3 below.
This will be explained with reference to FIGS. 4 and 5. The print head 104 is supported so as to be movable in the column direction (perpendicular to the plane of the paper in the second figure), and the platen 101 is rotatably supported to generate a feeding force for the paper 102. The paper presser roller 108 is rotatably supported by a paper presser roller shaft 109 arranged parallel to the platen 101, and the paper presser roller shaft 109 has both ends thereof supported by a fulcrum shaft 1.
10, and is supported by paper presser levers 107 arranged on both sides of the printer. Here, the connection between the paper press roller shaft 109 and the paper press lever 107 is such that a plurality of paper press rollers 108 are connected to the platen 101 via the paper 102.
In order to ensure uniform pressure contact and stable paper feeding, the cross-sectional shape of the paper presser lever shaft 109 is made into an irregular shape, such as an oval shape, and the paper presser lever shaft 109 is connected to the paper presser lever 107 in a slightly larger hole of the same shape to provide appropriate play. The paper presser lever 107 is held by the paper presser springs 111 installed on both sides of the printer.
The paper presser roller 108 is pressed against the paper presser roller 108 via. Further, the paper presser lever 107 has a release protrusion 107-
B and a protrusion 107-A. The paper presser release lever 116 is connected to the release protrusion 10 of the paper presser lever 107 on both sides of the printer.
7-B, and the release engaging parts 116-A on both sides of the printer are integrally formed by connecting parts 116-C. Furthermore, the paper presser release lever 11
There is a protrusion 116- on the side of the lock lever 112 of No.6.
It forms B. Also, paper presser release lever 1
16 is rotatably supported on both sides of the printer using a fulcrum shaft 110 of the paper presser lever 107 as a common fulcrum. Release solenoid 105
and paper presser release lever 116 are connection lever 1
06. lock lever 112
is rotatably supported around a lock lever shaft 113 as a fulcrum, and is pushed upward by a lock lever spring 114 to generate a locking force. Further, a protrusion 112-C is formed on the lock lever 112, and the lock lever 112 is held in the standby position by hitting the upper end surface 115-A of the hole of the frame 115. Furthermore, lock lever 112
A notch 112-B that engages with the protrusion 107-A of the paper presser lever 107 during manual release is formed in the notch 112-B, and a slope 112-A is also formed. Also, a paper feed roller 10 is provided around the platen 101.
3-1 and 103-2 are arranged and press against the platen 101 via the paper 102 to generate paper feeding force.

Next, the operation will be explained. When setting the paper automatically, first set the leading edge of the paper 102 at the contact point between the paper feed roller 103-1 and the platen 101, then energize the release solenoid 105 to release the paper presser lever 107, and then the platen 101 After rotating the paper 102 by a certain amount to send the leading edge of the paper 102 to the leading edge position 102-A, the platen 10
1 is stopped, the release solenoid 105 is energized, and the paper cutting lever 107 is returned to its original state. The release state at this time is shown in FIG. When the release solenoid 105 is energized, the paper presser release lever 11
6 is rotated about a fulcrum shaft 110, and the release force is transmitted by the release projections 107-B of the paper presser levers 107 on both sides of the printer, causing the paper presser levers 107 to rotate in the direction of arrow 117, thereby releasing the paper presser. The roller 108 and the paper 102 are released to a position where they do not interfere with each other. At this time, the paper presser release lever 1
16 of the protrusion 116-B pushes down the lock lever 112 along the slope 112-A, the protrusion 107-A of the paper presser lever 107
12 notches 112-B. Therefore, by turning off the power to the release solenoid 105,
The paper presser lever 107 is returned to the state shown in FIG. 2 by the paper presser spring 111.

When setting the paper manually, the paper presser lever 107 is manually released in the direction of arrow 117 as shown in FIG.
-1 and 103-2 are released by another release means (not shown) and released from the platen 101, and the paper 102 is set at an arbitrary position. When manually releasing the paper presser lever 107, the paper presser release lever 116 is
Since only the paper presser lever 107 rotates in the direction of arrow 117, the protrusion 107-A of the paper presser lever 107 and the notch 112-B of the lock lever 112 engage, and the lock lever 112 is pushed back by the slope 112-A of the The force of the lever spring 114 holds it in the state shown in FIG. After setting the paper 102, release the paper feed rollers 103-1 and 103-2, and manually move the paper presser lever 107 to arrow 1.
By returning to the opposite direction of 17, the state shown in FIG. 2 is restored.

<Effects> As described above, according to the present invention, when automatically setting paper, the paper presser release lever pushes down the lock lever so that the paper presser lever and lock lever do not engage, and only when manually setting paper, the paper presser lever and lock lever are pressed down. Since it is configured to engage, there is no risk of malfunction in which the paper presser lever is locked in the release position and does not automatically return during automatic setting. Therefore, the release position of the paper presser lever can be easily set to the same position during automatic setting and manual setting.
Furthermore, the difference in the release position of the left and right paper presser levers on both sides of the printer, which is caused by play in the connection between the paper presser lever shaft and the paper presser lever, is eliminated by using the paper presser release lever that connects the left and right paper presser levers as one unit. Therefore, the paper presser lever can be released in a small space without interfering with the print head or the like and at a position where it does not interfere with the paper. Therefore, the release operation is extremely reliable and stable, and the paper holding mechanism of a small printer can be used.

[Brief explanation of drawings]

Figures 1, 2, 3, 4, and 5 show embodiments of the present invention. Figure 1 is a front view schematically showing the paper holding mechanism, and Figure 2 is a front view showing the outline of the paper holding mechanism. Fig. 3 is a plan view of the lock lever, Fig. 4 is a side sectional view showing the release state when paper is automatically set, and Fig. 5 is the release state when paper is manually set. FIG. FIG. 6 is a side sectional view showing a conventional example. 101,201...Platen, 102,202
...Paper, 104,204...Print head, 10
7,207...Paper presser lever, 116...Paper presser release lever, 112...Lock lever, 10
5,205...Release solenoid.

Claims (1)

[Claims] 1. A paper holding mechanism of a printer capable of automatically feeding paper to a printing start position includes a platen that is rotatably supported and feeds the paper, a paper holding roller that presses the paper against the platen, and the paper holding roller. A rotatable paper presser lever that rotatably supports the paper, a paper feed lever drive means that retracts the paper feed lever to a position where it does not interfere with the fed paper, and a drive force of the paper feed lever drive means that controls the paper feed lever. A locking portion consisting of a paper presser release lever that transmits information to the presser lever, and a lock lever that holds the paper presser release lever at the retracted position, where the paper presser lever engages with the lock lever and is held at the release position during manual release. is formed on the lock lever, and a protrusion is formed on the paper presser release lever to move the lock lever to a position where the lock lever does not engage with the locking portion of the paper presser lever during automatic release by the paper feed lever driving means. A printer paper holding mechanism characterized by: