JPS59145176A - Printer - Google Patents

Abstract

PURPOSE:To enable to record even an image by a single drive source, by a method wherein a one-direction clutch is provided between a paper-feeding roller and a motor, and the length of reverse rotation of the motor is varied to obtain a plurality of paper-feeding pitches, in a printer capable also of recording an image. CONSTITUTION:When printing characters, a lead screw 29 is reversely rotated by one rotation by the motor 28, a paper is fed by a one-line amount by the contact of a ratchet roller 39 with a ratchet gear 36 through a clutch gear 37 and a paper-feeding gear 38, and a carriage is returned to a home position HP. In this case, the clutch gear 37 prevents the ratchet gear 36 from being rotated, so that the paper is prevented from being fed reversely. When recording an image, the lead screw 29 is rotated by 2/3 of rotation, whereby a line space of 2/3 of the above is obtained, and solid printing required for recording the image can be performed. Accordingly, a printing cycle can be performed by forward and reverse rotations of a single drive source, and both printing of characters and recording of images can be performed.

Description

[Detailed Description of the Invention] (Technical Field) The present invention relates to a printing device, and more specifically, to a printing device that moves a print head in the width direction of recording paper to print characters such as letters and numbers and to record images. It is related to.

(Prior Art) Various printing devices have been proposed in the past, but recently there has been an increasing demand for printing devices that can not only print characters such as letters and numbers but also record images.

In particular, there is a need for a small, inexpensive printing device that can hard copy images on a high-resolution (RT) display onto recording paper.

Normally, in this type of printing device, when printing characters such as letters, numbers, and symbols, a code signal specified in advance by the standard is sent from the control device side, and according to this signal, a certain line spacing is set. Characters are printed on the recording paper.

In the case of image recording, the image to be recorded is received as dot information and is recorded all over the recording paper without any line spacing.

In this way, it is necessary to change the line spacing between character printing and image recording. For this reason, in the past, a drive motor was provided to feed the recording paper separately from the print head feed, and the amount of paper feed was controlled.A zero-driven printing device of this type is shown in FIG. In FIG. 1, the reference numeral 1 designates a print head, which is configured as a thermal head in which a plurality of heating elements are arranged in a vertical line, for example. The print head 1 is fixed to a carriage 2, and the carriage 2 is slidably fitted to a guide rail 6. The upper end of the lever 4 is fixed to one end of the guide rail 6, and a tin ring 5 is stretched between the lower end of the lever 4 and the fixed part of the device, and the guide rail 6 is moved clockwise in the figure. A force is applied in the rotating direction, and the print head 1 is pressed against the grating 6 via the recording paper 7.

A solenoid 8 is provided on the opposite side of the lever 4 from the tin ring 5, and the tip of its lodge is fixed to the lower end of the lever 4 on the side opposite to the spring 5. Therefore, when the solenoid 8 is energized, the guide rail 6 is rotated counterclockwise, and the print head 1 can be rotated in a direction away from the recording paper 7.

The reference numeral 9 is a motor, and an endless wire 11 is stretched between a pulley 10 fixed to its output shaft and a driven pulley (not shown). is fixed, the carriage 2 is reciprocated as the motor rotates 90 times, a heating element (not shown) generates heat in accordance with a printing command, and printing is performed.

10, 12 is a paper feeding motor, and one end of a belt 14 is hung around a pulley 16 fixed to its output shaft, and the other end of the belt 14 is a paper feeding loaf 16.
is hung on a pulley 15 fixed to a fixed shaft 16&.

The recording paper 7 is guided between a paper feed roller 16 and a pinch roller 17, and a lever 18 formed approximately in the shape of a "<" is located at both ends of a shaft 17& on which a pinch solar 17 is rotatably supported. One set is rotatably supported on a shaft, and a spring ring 19 is stretched between the other end of the lever 15 and the device fixing part. This spring 19 causes the lever 18 to move clockwise around the bin 18a. The carriage 2 is moved by the motor 9 under a configuration of 0 or more in which the pinch roller 17 is pressed against the paper feed roller 16 and a frictional force is applied to feed the recording paper 7. When the carriage 2 is moved and one line of printing is completed, the carriage 2 returns to the home position, the solenoid 8 is energized, the guide rail 3 is rotated counterclockwise in FIG. 1, and the print head 1 is rotated. The recording paper 7 is lowered, the paper feeding motor 12 is driven, the recording paper 7 is advanced by one line, and the next printing operation is performed.

In addition, in the case of image recording, by controlling the amount of rotation of the motor 12, the intention to feed the paper is reduced (and solid recording is performed using dots). The head is moved by the motor 9, the print head is separated from the recording paper by the solenoid 8, and the paper is fed by the motor 12. This requires multiple drive sources, which increases the space occupied by the printing device. There was a limit to the miniaturization and cost reduction of the printer. (Purpose) The present invention was made to eliminate the above-mentioned drawbacks of the conventional printers. The object of the present invention is to provide a small and inexpensive printing device that can perform both character printing and image recording by moving the head and feeding the paper.

In order to achieve the above object, the present invention has a one-way clutch that connects the paper feed roller 2 and the motor in a printing device that performs a printing cycle in which the motor rotates in the forward and reverse directions. By changing the speed, multiple paper feeds can be obtained.

(Embodiment) Figure 2 and the following diagrams explain an embodiment of the present invention.
The figure shows the overall structure.

In Figure 2, the reference numeral 20 indicates a platen holder, and a platen 21 is attached to the front side of the platen holder. This platen holder 20 has a lower end Ocom roller shaft 22.
A spring 23 is elastically mounted between the side opposite to the platen 21 and a fixed part of a printing device (not shown), so that the printing device rotates toward the gear register, which will be described later. It is given.

Further, rubber rollers 24 are fixed to the comb roller shaft 22 on both sides of the laxative side of the platen holder 20. Pinch row R25 is located below and in front of the rubber roller 24.
are in contact with each other, and the recording paper 26 is held between them.

Further, on the 10,000-degree side of the platen holder 20, for example, on the left end in FIG.
is missing.

A lead screw 29, which is a cam member rotated by a motor 28, is arranged parallel to the platen 21 at a position facing the grating 21, and a gear register 60 having a female thread formed on the inner diameter is fitted into the lead screw 29. are combined. Therefore, when the motor 28 is rotated in the forward and reverse directions, the lead screw 29 also follows this and can reciprocate from side to side using the gear register 60 daughter lead screw 29. For example, a 1×8 dot circle V head 61 is provided, and this print head 31 is equipped with a spring 2.
3, the grating 21 is pressed.

Further, a protrusion 62 of a predetermined length is provided on the N surface of the gear register 30 on the side of the retaining portion 27 . This protrusion 62 is the gear register 6
0 returns to the home position, it is in a position where it can engage with the retaining portion 27. Gear register 30 is lead screw 29
It is guided by a guide rail 66 so as not to rotate with the zero rotation.

Further, the gear register 60 is provided with a set arm 64 that is slidable in the axial direction of the lead screw 29, and is given the habit of moving toward the home position by a spring 65. A ratchet gear 36 is rotatably attached, and this ratchet gear 66 is a clutch gear 6 including a one-way hook and a
It meshes with the paper feed gear 68 via 7. The paper feed gear 68 is fixed to one end of the rubber roller shaft 22.
The clutch gear 67 is configured to rotate only in the direction in which the recording paper is fed.

Further, a ratchet roller 69 is fitted on the lead screw 29 between the ratchet gear 66 and the gear register 60, and the ratchet roller 69 has a fully female thread on its inner diameter to fit with the lead screw 29, similar to the gear register 60. The ratchet roller 69 and the ratchet gear 66 are biased in a direction away from each other by the tin ring 40, and claw portions 41, 42 are provided on surfaces facing each other.

When the ratchet roller 69 and the ratchet gear 66 come into contact and the pawls 41 and 42 engage, the rotation of the ratchet roller 69 in one direction is controlled by the ratchet gear 66.
Also, the set arm 6
The set surface 46 on the opposite side of the gear register 30 of No. 4 serves to push the edge roller 69 to the left when the gear register 60 comes near the home position so that the ratchet gear 66 and the ratchet leaf 69 come into contact with each other. Next, the operation of the printing apparatus of this embodiment configured as described above will be explained.

During the printing operation, as shown in FIG. 6(a)
The platen holder 20 is pushed by a spring 26 and presses the printer 21 against the print head 61 via the recording paper 26. In this state, if the motor 28 is rotated in the forward direction and the lead screw 29 is rotated so that the gear register 30 moves to the right in FIG.
0 moves while being in pressure contact with the recording paper 26, and a heating element (not shown) generates heat according to the printing command, and printing is performed.
When printing is completed to the predetermined end position of one line in this way, the motor 28 rotates in the reverse direction, and the print head 61 returns to the home position together with the gear register 30. At this time, the ratchet row 269 and the ratchet gear 66 are separated from each other by the spring 40,
The 290 rotations of the lead screw are not transmitted to the edge gear 66, and the paper is not fed. Next, when the gear register 60 approaches the home position, as shown in FIG. 32 comes into contact with the cam surface of the retaining portion 27 and rides on it.

Since the gear register 30 can only move in the axial direction of the lead screw 29, the engaging portion 27 is pushed by the protrusion 62, and the platen holder 20 is rotated in the direction away from the print head 61 against the elastic force of the spring 260. When the gear register 60 approaches the home position, the set face 46 of the set arm 64 pushes the edge roller 39 to the left, causing the ratchet roller 39 and the ratchet gear 36 to come into contact with each other. When the lead screw 29 is further rotated, the gear register 60 moves further leftward from the home position to outside the printing range. Set arm 34
In order to maintain the position where the ratchet roller 69 and the ratchet gear 66 are in contact, the rotation of the lead screw 29 is transmitted to the ratchet gear 66, and the paper is fed.
By appropriately selecting the gear ratio of 8, it is possible to accurately feed the paper by one line with one rotation of the lead screw 29, for example.

Note that since the platen 21 and the print head 61 are separated from each other during paper feeding, the print head 61 does not interfere with paper feeding.

After the paper is fed in this way, the toss screw 29 is rotated in the opposite direction to move the gear register 60 to the right and return it to the home position.
6 tries to rotate in the reverse direction, but since the clutch gear 67 is in the direction in which it does not rotate, a force is applied that causes the ratchet roller 69 to separate from the ratchet gear 66, and the recording paper 26 does not return. Although the operating principle is as described above, paper feeding in each case of character printing and image recording will be explained next.

~・The heating element provided in the print head 61 is vertically 1
It is assumed that eight dots are provided in a column 0, and the line spacing in the case of normal character printing is L as shown in FIGS. - It is set to L/12 as shown in FIG. 6(b).

Further, the claw portions 41 and 42 of the ratchet gear 66 and the ratchet roller 69 are each provided at six locations at equal intervals.

When character printing is performed based on this structure, the motor is reversely rotated and the lead screw 29t-1 is rotated from the home position in the paper feeding direction, as shown in Fig. 6(a). , normal character
The paper is fed by one line corresponding to the printing line interval LK.

Next, in the case of image recording, as shown in FIG. A line spacing of
As shown in b), it becomes possible to perform solid printing necessary for image recording.

It should be noted that the present invention is not limited to the above-mentioned embodiments. For example, by changing the number rL of the claws 41 and 42 of the ratchet gear 66 and the ratchet row 269, the line spacing other than the normal character-printing line spacing can be changed. A line spacing that is an integer multiple of - is obtained. ':1''', that is, if rL = 3r, the line spacing is V3.2L/a, if n = 4, if
L/4, L/2, aL/4 are obtained.

It goes without saying that the present invention can also be applied to impact printers, inkjet printers, etc. other than thermal printers.

(Effects) As is clear from the above explanation, according to the present invention, one printing cycle can be performed by forward and reverse rotation of one drive motor, and character printing and image recording operations can be performed by changing the paper feed foot. By doing so, it is possible to obtain a compact and low-cost printing device.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an example of a conventional structure, and FIGS. 2 to 7 illustrate an example of the present invention. FIG. 2 is a perspective view, and FIG. 4(aJ)(1)l is an enlarged plan view and side view of the main part when the gear register 60 returns to its home position, and FIG. 5 is an enlarged side view of the main part during the printing operation. Enlarged plan view of main parts, No. 6
Figures (a) and (bl are an explanatory diagram of the paper feeding operation when performing gear printing and an explanatory diagram of the printing state, and Figure 7 (a)
)+ (1)) This is an explanatory diagram of paper feeding operation and an explanation of the recording state when performing line image recording. 1ψ・・Print head 211・Φ gear register 6・−・
Guide rail 411・ψLevel 51III・Sgeling 6-1 Platen 7...nself recording i
5---Solenoid 9.1 motor io
-■・Pulley 11 Fist 1・Endless wire 121
11III Motor 16 @1 pulley 14...
・Belt 15...Pulley 16-...Roller 17...Pinch roller 17a...Shaft 18...
Lever 182L...-pin 1j---spring 20...umbrella platen holder 21...platen 22...rubber 40-ra shaft 23-0 own spring 24-9...rubber roller 25...pinch roller
26... Recording paper 27... a combination M 28...
・Motor 29--- Lead screw 50---
Gear register 61... Print head 62... Protrusion 3 struggle - Guide rail 64, 9, Set arm 35 -
--Spring 36・-Meeting check gear 67・
Fog/Clutch gear 68...Paper feed gear 69/Hold/Ratchet roller 40...Spring 41.
42...Claw part 43...Set helmet opening °(0) A (b) To 2<0) (b) Drop q◇, % Go υ 35

Claims (1)

[Claims] A printing device that performs a printing cycle by forward and reverse rotation of a motor, has a one-way latte that connects the paper feed row 2 and the motor, and can perform multiple paper feeds by changing the length of the reverse rotation of the motor. The feature is that the pitch is obtained.