JPS59152884A - Printer - Google Patents

Abstract

PURPOSE:A printer wherein a head is fed at the time of forward rotation of a motor, and a paper is fed after returning the head to a printing starting point at the time of reverse rotation of the motor, so that a head-feeding operation and a paper-feeding operation can be selectively performed by a single motor. CONSTITUTION:When a driving motor 2 is rotated in the direction of an arrow A, a head-feeding screw 8 is rotated in the direction of an arrow C through gears 12, 15, 14, and the printing head 1 is moved from a home position. When the head 1 reaches the final end or when printing is completed at an intermediate position, the motor 2 is reversely rotated in the direction of an arrow B to return the head 1. When the head 1 is returned to the home position, it comes into contact with the tip of a push rod 11, thereby moving a change-over gear 15 through the rod 11, whereby engagement between a feeding gear 14 and the change-over gear 15 is released, and the movement of the head 1 is stopped. Simultaneously, engagement of a male screw part 16b of a paper-feeding gear 16 and a female screw part 15c of the gear 15 is started, and when the gear 15 and the gear 16 are united to each other, the paper is fed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a printing device, and more particularly to a real printer that prints characters, etc. on recording paper by reciprocating the dots.

(Configuration of conventional example and its problems) Conventionally, this type of printing device has been configured as shown in FIG.
Then, the feed shaft 3 is rotated and slid to reciprocate over the recording paper 5 wound around the paper feed roller 4 at right angles to the opposite paper feed direction. After the gutter 1 scans the printing and printing for one digit is completed, the second drive motor 2' rotates the feed roller 4 to feed the paper.

However, since this conventional example requires two drive motors 2 and 2', it has a bulky appearance and is expensive.

Therefore, a printing device that operates with a single drive motor as shown in FIG. 2 has been proposed. This conventional example is similar to the head feed shaft 3 and paper feed roller 4 of the conventional example shown in FIG.
are connected to the drive motor 2 via a one-way clutch 6 on the print side and a one-way clutch 7 on the paper feed/reverse side, respectively, and the drive motor 2' is eliminated. These two one-way directions,
Chiro and 7 transmit the rotation when rotating in the forward direction, and idle and do not transmit the rotation when rotating in the reverse direction, and the one-way crank on the printing side and the chiro are connected to the direct drive motor 2 by a gear. The one-way clutch 7 on the paper feed side is connected to the drive motor 2
are connected through one gear. Here, when the drive motor 2 rotates forward, the print side one-way clutch 6 rotates forward, the head feed shaft 3 rotates, and the nozzle 1 moves toward the print.
moves back and forth, and the one-way clutch 7 on the opposite side of paper feed rotates in the opposite direction, so that no rotation is transmitted to the paper feed roller 4.

Next, when the drive motor 2 rotates in the reverse direction, the print side one-way clutch 6 rotates in the reverse direction υ, and the movement of the lead 1 to print stops, and the paper feed side one-way clutch 7 rotates in the forward direction, causing the paper feed roller 4 rotates, and the recording paper 5 is fed.

However, in the conventional example described above, paper feed usually goes to printing.
This is performed only when the print head 1 is in the home position, that is, the printing start position, and the print head 1 scans from left to right.
Always the leftmost home month? You cannot return to the home position unless you scan from No/Yon to the right end. However,
Printing is not always from the edge of the recording paper 5 to the edge, and often ends mid-way, so the gutter 1 scans in vain for the round trip from the point where printing ends to the right edge, etc. There was a drawback.

(Object of the invention) The present invention has been made in view of the drawbacks of the above-mentioned conventional examples, and
It operates with only one drive motor, and when printing ends in the middle of a line, it directly prints on the home button/controller, and then returns.
The present invention provides a printing device that can subsequently feed paper.

(Structure of the Invention) In order to achieve the above object, the present invention moves a print head by rotating a head feed screw using a drive motor.1. Depending on the direction of rotation of the drive shaft, the print head moves away from the home position during forward rotation, and returns to the home position during reverse rotation.

Also, [Go to white text.

When the drive motor further rotates in the reverse direction while the head is in the home position, the switching gear switches from the head feed side to the paper feed side, and the paper feed roller rotates to feed the paper.

(Description of Embodiments) Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 3(a) and 3(b) are a plan view and a front view, respectively, showing the configuration of an embodiment of the present invention, and FIGS.
Items with the same reference numerals as those in the figures indicate the same items. In FIG. 3, drive motor 2. The feed roller 4 and the feed screw 8 are installed at predetermined positions on the frame 9 with their respective shafts passing through the frame 9 at right angles. Further, reference numeral 10 denotes a head guide shaft that slidably holds the printing dot 1, and is installed on the frame 9 so as to be parallel to the paper feeding roller 4 and the printing dot feeding system screen 8.Here, The head feed screw 8 has a spiral groove, and this groove engages with the protruding part of the print head 1, and the rotation of the head feed screw 8 causes the head feed screw 8 to move the print head along the head guide shaft 10. 1 moves. Reference numeral 11 denotes an extrusion rod that is installed through the frame 9 so that its tip comes into contact with the print head.Furthermore, the frame 9 of the driving moke 21, the paper feed roller 4, and the head feed roller 8 is moved.
At the tip of each shaft protruding through the motor vehicle 1
21 paper feed gear 13 and a paper feed gear 14 are respectively attached. Furthermore, a switching gear 15 and a paper feed 9 drive gear 16 that mesh with these gears are installed on the frame 9. The switching gear 15 and the forward drive gear 16 are constructed as shown in FIG. 4. Switching gear 1
5 has a shape in which two gears of different diameters, a motor side gear 15a and a head feed side gear 15b, are coaxially superimposed, and has a hole in the center of which a female threaded portion 15c is formed. . Further, the paper feed drive gear 16 has a tubular member extending from the gear portion 16a.
It consists of a male threaded portion 16b with a nearby male thread formed thereon and a pipe portion 16c without a male threaded end hook. and,
The guide portion 16c of the paper feed 9 drive gear 16 is the switching gear 15.
The switching gear 15 is inserted into a hole having a female threaded portion 15c.
is rotatably held by a paper feed drive gear 16, and the paper feed drive gear 16 is rotatably held by a paper feed drive gear shaft 17 passing through its center and mounted on the frame 9. There is. At this time, the head feed side gear 1 of the switching gear 15
The switching gear 15 and the paper feed drive gear 16 are arranged so that the bottom of the pusher 5b comes into contact with the head of the extrusion rod 11 that passes through the frame 9.
is positioned. In addition, the switching gear 15 has its motor side gear 15a and head feed side wheel 15b meshing with the motor gear 12 and the head feeder 9 wheel 14, respectively.
A gear portion 16a of the paper feed drive gear 16 meshes with the paper feed 9 gear 13.

Next, the operation of this embodiment will be explained. In FIG. 3(a), when the drive motor 2 rotates in the direction of arrow A in the figure,
Motor gear 12. Switching gear 15. fart.

The rotation is transmitted to the feed gear 14, and the feed screw 8 rotates in the direction of arrow C. At this time, the printing pad 1 moves in a direction away from the home position, that is, from left to right in the figure, and printing is performed. Then, when the print head 1 moves to the opposite end, or when printing ends in the middle of a line, the drive motor 2 is reversely rotated in the direction of arrow B, causing the head feed system screw 8 to rotate. The rotation is also reversed and rotates in the direction of the arrow, and the print head 1 moves in the direction in which it returns to its home position, that is, from the right to the left in the figure.

In this way, to print, after Do 1 returns to the home position,
Further rotate the drive motor in the direction of arrow B to
When the printing rod 1 is brought into contact with the tip of the extrusion rod 11 that passes through the printer, and the extrusion rod 11 is pushed out in the direction of the switching gear 15, that is, in the left direction in the figure, the switching gear 15 moves as shown in FIG. do. Note that FIG. 5 shows a cross section passing through the center of each gear shaft in order to explain the meshing of the gears. Go to print.

The head of the push rod 11 pushed leftward in the figure by the pusher 1 presses the bottom of the switching gear 15, and the switching gear 15 moves over the paper feeding reverse drive gear 16 7 and the rib portion 16c in the direction of the gear portion 16a. and finally the male threaded portion 16b of the paper feed reverse drive gear 16.
and the female threaded portion 15c of the switching gear 15 begin to screw together. Up to this point, the head feed side gear 15b of the switching gear 15
Since the head feed gear 14 and the head feed gear 14 are in mesh with each other, the head feed gear 8 is rotated by the rotation of the drive motor 2. However, when the male threaded portion 16b of the paper feed drive gear 16 and the female threaded portion 15c of the switching gear 15 are screwed together, the switching gear 15 is rotated by the motor gear 12 in the direction of arrow E in the figure, and the male thread is rotated. along the section 16b toward the gear section 16a;
That is, since it moves to the left, the head feed side gear 15b of the switching gear 15 and the head feed gear 14 are disengaged, and the rotation of the head feed screw 8 is stopped. Then, the switching gear 1
5 rotates and the switching gear 15 moves to the end face of the gear portion 16a of the paper feeding reverse drive gear 16, as shown in FIG. The paper feed gear 13 is always meshed with the gear portion 16a of No. 16.
rotates, and the recording paper 5 wound around the paper feed roller 4
is fed in proportion to the number of rotations of the drive motor 2.

After feeding the paper by a predetermined length, the drive motor 2i is rotated in the direction of the arrow in FIG. 3, and the switching gear 15 is rotated in the direction of the arrow F in FIG. Then, due to the action of the male threaded portion 16b and the female threaded portion 15c, the switching gear 15 starts to move away from the end surface of the gear portion 16a of the paper feed drive gear 16, that is, to the right in the figure. Switching gear from this point]
5 is no longer engaged with the paper feed 4 drive gear 16, the paper feed drive gear 16 stands still, and therefore the paper feed of the recording paper 5 also stops. At this time, there is a possibility that the paper feed driving gear 16 rotates together with the switching gear 15 due to the frictional force with the switching gear J5, so the gear portion 16a of the paper feeding driving garden wheel 16 is rotated in the opposite direction using a ratchet mechanism or the like. Just try not to.

After paper feeding has stopped, when the switching gear 15 is further rotated and moved in a direction away from the gear portion 16a of the paper feeding drive gear 16, the state shown in FIG. 5 is reached, and the switching gear 15
The end surface of the head feed 9 side gear 15b contacts the extrusion rod 11, pushing the extrusion rod 11 into the print head 1 side, and the head feed side gear 15b is fed! ll gear 14, and the print head 1 begins to move away from the home position. By repeating the above operations, printing and line feed can be continued.

Note that when the switching gear 15 and the head feed gear 14 are separated by 9 and then engage again, the head feed gear 14 is stationary while the switching gear 15 is rotating.
There is a possibility that the two may be difficult to mesh with each other. Therefore, switching gear 1
5 and the head feed gear 14 engage, the drive motor 2
By lowering the rotation speed of the two, it becomes easier to engage the two.

Further, as shown in FIG. 7, the head feed gear 14 is slidably held on the shaft of the head feed screw 8, and is usually biased toward the end of the shaft of the head feed screw 8 by a coil spring 18. By configuring the
While the head feed gear 14 is being pushed and moved by the switching gear 15, they are completely meshed with each other, so that the switching gear 15 and the head feed gear 14 can be re-engaged smoothly.

Furthermore, by making the head feed side gear 15b and hend feed gear 14f of the switching gear 15 helical gears, it is possible to more easily re-mesh the switching gear J5 and the head feed gear 14. becomes.

Further, when the switching gear 15 re-meshes with the head feed gear 14, the pushing rod 11 is pushed into the frame 9 again, but this becomes a significant load for the re-meshing of the switching gear 15 and the head feed gear 14. Therefore, by applying a biasing force to the extrusion rod 11 in the direction of pushing it into the frame 9 using a spring or the like, the print head 1 is moved forward to the switching gear 15 at the moment when it is disengaged from the gear 14. Push it back with the push rod 11, and make sure that no load is applied to the switching gear 15 and the feed gear 14 meshes with it again.

(Effects of the Invention) As explained above, the present invention allows the print head to be returned to the home position even from the middle of a line during printing, thereby shortening the printing time. Since the drive motor is comprised of a drive motor, the outside size can be reduced in size and costs can be reduced, among other effects.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a conventional printing device, FIG. 2 is a perspective view of another conventional printing device, and FIGS. 3(a) and (b) are
A plan view and a front view of an embodiment of the present invention, 4th
The figure is a cross-sectional view of a switching gear and a paper feed drive gear according to an embodiment of the present invention, FIGS. 5 and 6 are cross-sectional views of the embodiment of the present invention during operation, and FIG. FIG. 9 is a sectional view of a head feeder gear according to another embodiment of the invention. 1. To print, 2. Drive motor, 4. Paper feed roller, 5. Recording paper, 8. Head feeding system screw, 10. Head guide shaft, 11. Push rod, 12・
・Motor gear, 13...Paper feed gear, 14・Head feed 9 gear, 15...Switching gear, 15a...Motor side gear, 15b...Head feed side gear, 15c・Female thread part, 16 ・Paper feed drive gear, 16a... Gear part, 16
b...Male thread part, ]6c...Pipe part. Figure 1 Figure 3 +01 Figure 4 Figure 5 Figure 6 Figure 7

Claims (1)

[Scope of Claims] (1) A print head, a means for feeding the recording paper, a means for feeding the paper to move the print head perpendicularly to the opposite direction of paper feeding of the recording paper; a drive motor serving as a drive source for the paper feed means and the head feed means; and a gear device that switches and transmits the rotation of the drive motor to the paper feed means and the head feed means; When the gear rotates in the forward direction, rotation is transmitted to the head feeding means by the gear device, the print head moves and prints, and at the point where printing is completed, the drive motor rotates in the reverse direction, causing the print head to move when printing. and when the drive motor rotates in the opposite direction, the gear device is switched and the rotation is transmitted to the paper feeding means to perform unfeeding. printing device. (2) The gear device includes a paper feeding gear that drives the paper feeding means, a head feeding gear that drives the head feeding means, a motor gear that transmits rotation of the drive motor, and a paper feeding gear that drives the paper feeding means. a paper feed drive gear having a gear part that meshes with the gear part and a tubular member having a male threaded part only in the vicinity of the gear part extending therefrom; and a paper feed drive gear rotatably held in the tubular part of the paper feed drive gear. and has a female threaded portion on a part of its inner diameter portion, rotates the head drive gear in response to rotation of the motor gear, and is screwed into the male threaded portion of the tubular member of the paper feed drive gear. a switching gear for rotating the paper feed driving gear; and means for moving the switching gear and switching the gear device depending on the position of the print head and the rotational direction of the drive motor; The head feeding gear is rotated forward or backward from the motor gear via the switching gear, and when feeding paper, the gear device switching means disengages the engagement between the switching gear and the head feeding gear. Then, the switching gear and the paper feed driving gear are screwed together, and rotation is transmitted from the motor gear to the paper feeding gear via the switching gear and the paper feeding drive gear, and in the gap for printing again, the switching gear is screwed together. Claim 1 is characterized in that the switching gear is unscrewed from the paper feed gear and the drive gear, and the switching gear is re-engaged with the head feed gear.
) Printing device described in section. (3) Claim (2) characterized in that the paper feed drive gear has a ratchet mechanism for preventing reverse rotation.
Printing device as described in section. (4) The printing device according to claim 2, wherein the rotational speed of the drive motor is lowered when the switching gear and the forward and backward gears engage again. (5) The printing device according to claim (2), wherein the head feeding gear is slidable on the shaft of the head feeding means and biased toward an end of the shaft. . (6) The printing device according to claim (2), wherein the mutually meshing portions of the switching gear and the feed side wheel are helical gears. (7) The gear mechanism switching means includes a mechanism for pushing back the print head when the switching gear and the feed gear are disengaged. ) Printing device described in section 2.