JPS6325168Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mechanism for controlling the rotation of a printing roller just before the end of printing in a printer that presses and rotates selected characters at a printing position to print.

A conventional small-sized printer has a type ring and a selection claw that selectively locks the type ring, and prints the selected type on the printing paper by pressing the selected type at the print position from below while rotating through the printing paper. In this type of device, the printing roller presses and rotates the type, and just before the end of printing, the reaction force of the printing roller causes the printing roller and the type to suddenly move in the direction of separation. Sudden movements can impact the printing paper or cause collisions with parts, such as gears, that drive the printing roller, both of which generate extremely loud noises. Further, the rapid movement of the type wheel has the disadvantage that the type that should not be printed, in this case the upper type, collides with the printing paper and appears as dirt on top of the normally printed characters.

In order to eliminate these drawbacks, the present invention provides printing roller rotation prevention members on both sides of the printing wheel to control the rotation of the printing roller.
While pressing and rotating the selected type at the printing position, the reaction force of the print roller causes the print roller and type to
The purpose is to prevent large noises and print stains by preventing sudden movement away.

The features of the present invention include a type wheel with type provided on its outer periphery, a type wheel shaft rotatably supporting the type wheel, and a type wheel shaft that selectively engages with the type wheel and is rotated by the type wheel shaft. a selection means for selectively locking arbitrary type on the type wheel at a printing position; a printing roller for rolling and pressing on the type selectively locked at the printing position to print on the printing paper; a printing roller support member that rotatably holds the roller and rotates around a central axis; a frame member that guides and supports the type wheel shaft; and a frame member that is fixed to the type wheel shaft or the frame member so that its tip is in the printing position. a printing roller located at approximately the same position as the selectively locked printing type, and formed such that the printing roller presses and rotates on the printing type, and the tip portion receives the pressing force of the printing roller just before the end of the rotation; 1 is a print roller control mechanism for a small printer characterized by comprising a rotation prevention member.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan cross-sectional view of a small-sized printer according to the present invention, in which numeral 11 indicates a type wheel with type 111 provided on its outer periphery, and numeral 12 indicates ratchet teeth 11 provided on the type wheel 11.
2, a selection means for selectively locking a desired type at a printing position; 13, a type wheel shaft rotatably supporting the type wheel 11; and 14, a selected type 111 is rotated and pressed onto printing paper 18. A printing roller 16 for printing rotatably supports the printing roller 14,
This rotation center is a printing roller support having an eccentric rotation center, and 17 is the central axis. Reference numeral 15 denotes a printing roller rotation prevention member provided adjacent to the type wheel 11, and is adapted to engage with an end of the printing roller 14 via a spring portion 21. The spring member 21 serves to press the printing paper 18 toward the printing roller. The printing roller rotation prevention member 15 is connected to the type wheel shaft 13
is engaged with a groove in the type wheel shaft 13 so as not to rotate.

FIG. 2 is a side sectional view of the type wheel 11 and printing roller 14 portion. 19 connects the type wheel 11 to the type wheel shaft 13
This is a type ring spring that frictionally engages the two. Third
The figure is a side view of the print roller rotation prevention member.

The operation of a small printer having these configurations will be explained. First, in the selection process, when the type wheel shaft 13 rotates in the direction of the arrow and the desired type 111 comes to the printing position, the selection means 12 is driven to lock the ratchet teeth 112 of the type wheel 11 and stop the rotation of the type wheel 11. stop. The type wheel shaft 13 further rotates in the direction of arrow a, but the type ring spring 19 comes off the groove of the type wheel shaft 13, and the type wheel 11 can be easily locked.
When all the digits of the type wheel are selected, the type wheel shaft 11 stops rotating. Next, in the printing process, the shaft 17 rotates in the direction of arrow b, and the printing roller 14 rotates and presses the type 111 from below through the printing paper 18 to print. At this time, the end of the printing roller 14 also presses the printing roller rotation prevention member 15. Since the printing roller rotation prevention member 15 is fixed to the type wheel shaft 13, it will not rotate due to the reaction force of the printing roller 14. After printing, the type wheel shaft 13 is counter-rotated again to reset the type wheel 11 to its original state.

In such a structure, the printing roller 14 is connected to the type 111.
At the last part of the press and rotation, the force relationship is as shown in Fig. 4, and the printing wheel 11 rotates clockwise, and the printing roller 14 rotates in the direction of arrow c, while suddenly moving in the direction of arrow d. It works to move, but
Here, the printing roller 14 presses a printing roller rotation prevention member 15, and since this printing roller rotation prevention member 15 is fixed to the type wheel shaft 13, it prevents the printing roller from moving in the directions of arrows c and d. .

This also prevents the type wheel 11 from rotating in the right direction. That is, the printing roller rotation prevention member functions to hold down the printing roller just before the end of printing, and controls the movement of the printing roller and the type wheel. Therefore, since these movements can be eliminated, it is possible to prevent both the generation of noise due to the sudden movement of the printing roller and the occurrence of printing stains due to the sudden reversal of the type wheel.

In FIG. 1, the printing roller rotation prevention member 15 is fixed to the type wheel shaft 13, but the same effect can be obtained even if it is fixed to the frame 20.

Further, in FIG. 1, the printing roller rotation prevention member 15 comes into contact with the printing roller via a spring member 21 which is used to press the printing paper between the printing roller 14 and the printing roller toward the printing roller. It's not something that goes outside the box.

As explained above, when the print roller presses and rotates the type, by engaging the print roller with the print roller rotation prevention member that is fixed to prevent rotation, the reaction force between the print roller and the type wheel can be prevented. Sudden movements can be eliminated, thereby preventing the generation of noise. Furthermore, since there is no sudden movement of the printing wheel, it is possible to eliminate stains caused by adjacent printing characters that occur above printed characters.

Furthermore, since there is no sudden movement of the printing roller, the speed at which the characters are pressed is almost constant, and the printed characters appear as clear characters with little shading. Thus, it has the effect of being able to print clear characters with less noise and no printing stains.

[Brief explanation of drawings]

FIG. 1 is a plan cross-sectional view of the printing roller control mechanism of a small printer according to the present invention, in which 11 is a type wheel;
2 is a selection means, 14 is a printing roller, and 15 is a printing roller rotation prevention member. FIG. 2 is a side sectional view of the printing roller control mechanism of the small printer according to the present invention. FIG. 3 is a side view of the printing roller rotation prevention member. FIG. 4 is a diagram showing the force relationship between the printing roller and the type wheel just before the end of printing.

Claims (1)

[Scope of utility model registration request] A type wheel having type on its outer periphery, a type wheel shaft rotatably supporting the type wheel, and any type on the type wheel that selectively engages with the type wheel and is rotated by the type wheel shaft. a printing roller that rolls and presses onto the printing paper selectively locked at the printing position to print on the printing paper; and a printing roller that rotatably holds and centers the a printing roller support member that rotates around a shaft; a frame member that guides and supports the type wheel spindle; and approximately the type that is fixed to the type wheel spindle or the frame member and whose tip is selectively locked at the printing position. and a printing roller rotation prevention member located at the same position and formed so that the printing roller presses and rotates on the type and the tip part receives the pressing force of the printing roller just before the rotation ends. Features a printing roller control mechanism for small printers.