JPH0145432B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a printer that prints using sprocket paper.

Technical background of the invention and its problems Conventionally, as printers that print using sprocket paper, there are push-in type printers in which the sprocket paper is sent to the lower outer periphery of the platen by a tractor and discharged from the upper outer periphery of the platen after printing, and There is a tension type in which a sprocket paper fed to the outer periphery is pulled out from the upper outer periphery of the platen by a tractor after printing. The push-in method is
Although the sprocket paper can be cut near the platen after printing, the sprocket paper tends to float away from the platen, resulting in uneven printing positions. In addition, with the tension type, the sprocket paper is pulled in close contact with the platen to ensure accurate printing position, but in order to cut the sprocket paper, the sprocket paper must be pulled out from the top outer periphery of the platen to the rear of the tractor. This increases the margin space and consumption of sprocket paper. in this way,
The push method and the tension method have both advantages and disadvantages, so when cutting sprocket paper at predetermined pitches, a push method printer is used, and when the sprocket paper is continuously fed, a tension method is used. It is necessary to use a standard printer.
Therefore, two printers must be kept on hand depending on the purpose of use.

Purpose of the Invention The present invention has been made in view of the above-mentioned points, and it is possible to obtain a usage pattern in which the sprocket paper is sent to the platen by a tractor and a usage pattern in which it is pulled out from the platen depending on the purpose of use, and further,
The object of the present invention is to provide a printer in which the paper feed pitch can be equally determined by a tractor in any usage mode.

Summary of the Invention This invention rotatably holds both ends of a drive shaft that rotates integrally with the drive wheels of a tractor by a pair of left and right plates, and rotates the plates downward to supply the drive shaft from the tractor to the lower outer periphery of the platen. Suitable for cutting the sprocket paper at predetermined pitches by determining the path of the sprocket paper to be cut and transmitting the rotation of the platen gear connected to the rotating platen to the tractor gear of the tractor drive shaft via the lower intermediate gear. In addition, the plate can be rotated upward to determine a path for the tractor to pull out the sprocket paper from the upper outer periphery of the platen, and the rotation of the platen gear can be transferred to the tractor via the upper intermediate gear. The rotation of the platen gear is transmitted to the tractor gear of the drive shaft of the sprocket, which can be used as a tension method suitable for continuous feeding of sprocket paper. By transmitting the power to the tractor gear via a gear, the paper feed pitch by the tractor can be set equally, and the power can be transmitted with a simple structure.

Embodiment of the Invention An embodiment of the invention will be described based on the drawings.
A platen 3 is rotatably held by opposing side plates 1 and 2, and a platen gear 4 and a dial 5 are fixedly fitted to one end of the platen 3.
Further, a print head 6 is provided opposite the platen 3.

Next, a pair of left and right plates 7 facing each other inside the side plates 1 and 2 are provided, and these plates 7 hold a support shaft 8 and a drive shaft 9. A pair of left and right tractors 10 are held so as to be slidable and fixed at any position. These tractors 10 include a drive wheel 11 that rotates integrally with a drive shaft 9, an annular belt 12 that has many pin-shaped protrusions on the outer periphery and is driven by the drive wheel 11, and a sprocket attached to the belt 12. It has a rotatable presser plate 14 that presses the paper 13. The side plates 1 and 2 have U-shaped bearing portions 1 that support both ends of a support shaft 8 that is the center of rotation of the plate 7.
5 is notched, and a notch 16 is formed for regulating the amount of deviation of the drive shaft 9 with the support shaft 8 as a fulcrum.

Further, on the right side plate 1, there is a drive gear 18 directly connected to the motor 17, and reduction gears 19 and 20 that transmit the rotation of the drive gear 18 to the platen gear 4.
, two intermediate gears 21 and 22, and an idler gear 23 are supported. Teeth portions 21a, 22 that constantly engage the intermediate gears 21, 22 with the platen gear 4
a and small-diameter tooth portions 24b, 22b.
The tooth portions 21a and 22a have the same diameter and the same number of teeth, and the tooth portion 2
1b and 22b also have the same diameter and the same number of teeth. Also,
A tractor gear 24 that is selectively meshed with the teeth 21b or the idler gear 23 is fixed to one end of the drive shaft 9. Idler gear 23 always has teeth 22
It is meshed with b.

Furthermore, the plates 7 are provided on the inner surfaces of the side plates 1 and 2.
A holding mechanism 25 is provided that resiliently holds the holder at predetermined upper and lower positions. These holding mechanisms 25 are made of plate material and are supported by springs 26.
It is held slidably while being biased toward the support shaft 8 from between the intermediate gears 21 and 22.
Slopes 27 are formed on both shoulders of the holding mechanism 25 to divide the center and press the drive shaft 9 against one end of the notch 16.

Further, on the outside of the left side plate 2, a lock plate 28 for locking the plate 7 in the upper position is biased toward the support shaft 8 by a spring 30, and the pin 29
It is held rotatably around the center. As shown in FIG. 7, the lock plate 28 is formed with an upwardly facing step 31 and a knob 32 for supporting the drive shaft 9.

Furthermore, as shown in FIGS. 4 and 5, a path 33 extending from the rear to the lower outer periphery of the platen 3 and a path 34 extending from the bottom to the platen 3 are formed by opposing guide plates. There is. These paths 33, 34 are for passing the sprocket paper 13 or ordinary long paper, and paper detection switches 35, 36 are provided in the paths 33, 34.
Furthermore, a pinch roller 37 and a paper bail roller 38 are provided to selectively contact the platen 3.

In such a configuration, the rotation of the motor 17 is transmitted to the platen 3, and the platen 3 is rotated as shown in FIGS.
It always rotates clockwise in the figure. When cutting the sprocket paper 13 from perforations at predetermined pitches, a push-in method is used as shown in FIGS. 2 and 4. That is, the plate 7 is rotated downward to engage the tractor gear 24 with the idler gear 23. As a result, the rotation of the platen gear 4 is transmitted to the tractor gear 24 via the intermediate gear 22 and the idle gear 23, the drive shaft 9, the drive wheel 11, and the belt 12 rotate counterclockwise, and the sprocket paper 13 is rotated on the platen 3. It is sent to the lower outer periphery. The printed sprocket paper 13 is cut at the portion past the paper bail roller 38. This position is close to the tip of the print head 6, and can print up to the vicinity of the cut edge, reducing the margin and preventing wastage of the sprocket paper 13.

The use of the tension method in which printing is performed by continuously feeding the sprocket paper 13 is achieved by rotating the plate 7 upward as shown in FIGS. 3 and 5. The tractor gear 24 is directly meshed with the teeth 21b of the upper intermediate gear 21, and is connected to the drive shaft 9 and the drive wheel 11.
The belt 12 rotates clockwise, and the sprocket paper 13 fed from the path 33 to the platen 3 is rotated clockwise.
is pulled upward by the tractor 10. As a result, the sprocket paper 13 does not loosen around the outer periphery of the platen 3, and uniform printing can be achieved. In such a tension mode of use, the sprocket paper 13 may be fed from the lower path 34. Alternatively, it is also possible to obtain a mode of use in which plain paper is fed from the path 33, pinched by the pinch roller 37 and the platen 3, and fed without using the tractor 10.

In this way, the posture of the plate 7 can be changed in the vertical direction, but as shown in FIGS. Therefore, the plate 7 stands still in either the upper or lower position. Actually, since the slope 27 presses the collar 9a fitted to the drive shaft 9, the drive shaft 9 rotates smoothly. If the plate 7 is located above, it may be accidentally pressed downward, but as shown in Fig. 7b,
Since the stepped portion 31 of the lock plate 28 is located below the drive shaft 9, it will not fall downward. When the plate 7 is lowered to the lower position using the push-in method, the spring 30 is bent and the lock plate 28 is rotated to the right from the state shown in FIG. 7b. When rotating the plate 7 from the bottom to the top, the lock plate 28 is pushed by the plate 7 and temporarily retreats, but then returns immediately by the force of the spring 30.

Effects of the Invention Since the present invention is configured as described above, it can be used as a pushing method suitable for cutting sprockets at predetermined pitches by moving the plate up and down, and suitable for continuously feeding sprocket paper. In addition, since the two intermediate gears that transmit the rotation of the platen to the tractor gear have the same diameter and the same number of teeth, the tractor can be used in both push and pull modes. This has the advantage that the paper feeding pitch can be made equal, and the power transmission mechanism for obtaining the two types of use can be extremely simplified.

[Brief explanation of drawings]

The drawings show one embodiment of the invention.
The figure is a plan view, Figure 2 is a side view showing the power transmission path using the push method, Figure 3 is a side view showing the power transmission path using the tension method, and Figure 4 is a longitudinal section showing the path of the sprocket paper using the push method. Side view, 5th
The figure is a vertical side view showing the path of the sprocket paper in the tension method, and Figure 6 is the A-A in Figure 1.
FIG. 7 is a partial longitudinal side view showing the operation of the holding mechanism taken in cross section along the line, and FIG. 7 is a partial side view showing the operation of the lock plate. 3...Platen, 4...Platen gear, 7...Plate, 9...Drive shaft, 10...Tractor, 11...Drive wheel, 17...Motor, 21, 22...Intermediate gear, 24
...Tractor gear.

Claims (1)

[Claims] 1. A platen with a platen gear driven by a motor fixed at one end is rotatably provided, and a pair of left and right plates are provided with an axis parallel to the platen so as to be movable up and down and fixed at a predetermined position, Both ends of a drive shaft that rotates integrally with the drive wheel of the tractor are rotatably attached to the free rotation end sides of these plates, and a tractor gear is fixed to one end of the drive shaft, and the diameter and number of teeth are set to be the same. The printer is characterized in that two intermediate gears are arranged at two predetermined positions, upper and lower, and are always meshed with the platen gear to selectively transmit rotational force to the tractor gear, either directly or indirectly.