JPH02184480A - Recorder - Google Patents

Abstract

PURPOSE:To commonly use one drive source for a plurality of driving mechanisms, to largely reduce the cost of a recorder and to reduce in size it by composing a switching mechanism of a plurality of differential gear units, and forming the plurality of differential gear units in a structure in which the output of the unit of a front stage is so coupled in series as to be the input of the unit of a rear stage. CONSTITUTION:When a lock rod 11 is moved in size slightly larger than the width of protrusions 11c, 11k in cooperation with a carriage 2 in a direction (a), a bevel gear 15e is locked by a protrusion 11a, but bevel gears 15d, 14e are opposed to recesses 11d, 11l, and the lock is released. A bevel gear 14d is locked by a protrusion 11m. When a rotary driving force is input from a gear 13, a bevel gear 14e and a rotor 15a integral therewith are rotated, the bevel gear 15d is rotated, and a rotary drive force is transmitted to a gear 16, thereby driving an automatic sheet feeder. That is, a plurality of differential gear units are coupled in series to simply and inexpensively construct a driving force switching mechanism for switching in multiple stages.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printing apparatus, and more particularly to a serial type printing apparatus that performs printing scanning by moving a carriage mounted on a printing head.

U. Prior Art FIG. 4 illustrates a conventional printing apparatus of this type, and shows, for example, a serial type inkjet printer used as a printing output apparatus for a personal computer. In this printer, a carriage 31 on which a recording head (inkjet head) 30 is mounted is connected to a platen 3.
2 as shown by arrows a and l) to perform one line of recording scanning. When the recording scan of the - line is completed, the platen 32 is rotated as shown by arrow C, the recording paper of the unillustrated claw is fed, and a line feed is performed. Further, this printer is provided with a recovery device 33 in order to prevent ink from being ejected from the nozzles of the recording head 3o and to recover the ink from the ejection failure to a normal state. When the carriage 31 returns to the home position at the left end in the figure, the recovery device 33
The nozzles of the recording head 30 are capped by this operation. Further, the recovery device 33 is driven as necessary to perform a recovery operation from a discharge failure.

In such a printer, there is a driving force for moving the carriage 31, a driving force for rotating the platen 32 and feeding the recording medium, a driving force for operating the recovery device 33, and an automatic driving force for automatically feeding the recording paper. If a sheet feeder is provided, its driving force is also required. In the general configuration of conventional printers, one driving source (mainly a motor) is provided for each of these necessary driving forces.

[Problems to be Solved by the Invention] However, providing a drive source for each drive mechanism of the printer in this way increases costs, and requires a drive driver, an I10 port, and wiring for each drive source, which increases the cost. It also costs a lot of money. Another drawback is that it hinders miniaturization of printers.

Therefore, a configuration is adopted in which the driving force of one driving source is commonly used for a plurality of driving mechanisms in the printer. In this case, a driving force switching mechanism is provided that switches and transmits the driving force of a common driving source to a plurality of drive mechanisms. In the structure of conventional drive force switching mechanisms, the drive force is transmitted by a gear train, and the transmission of the drive force is switched by moving the gears relative to each other and switching the meshing of the gears. ing.

However, with this method, the gears that are switched and engaged will not mesh properly unless the positions of the teeth and interdental grooves match accurately. If it were to be constructed so that this switching of engagement could be performed accurately and smoothly, the structure would be complicated and expensive. In particular, when the number of switches increases, the structure becomes extremely complex and expensive.

SUMMARY OF THE INVENTION An object of the present invention is to provide a recording apparatus having a simple and inexpensive structure and a driving force switching mechanism capable of accurately and smoothly switching the driving force in multiple stages.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention provides a printing apparatus that performs printing scanning by moving a carriage on which a printing head is mounted. It has a driving force switching mechanism that switches and transmits the driving force of one drive source, and the switching mechanism is composed of a plurality of differential gear devices, and the plurality of differential gear devices are configured to switch between the output of the preceding device and the output of the subsequent device. A series-connected structure was adopted to serve as the input for the device.

[Function] The reason for this type of structure is that only the gears in the differential gear device that constitute the driving force switching mechanism are always in mesh with each other.
The switching of the driving force transmission can be performed accurately and smoothly by selectively locking or unlocking the output gear of the differential gear. Further, by connecting a plurality of differential gear devices in series to form a driving force switching mechanism as described above, a mechanism capable of performing multi-stage switching can be easily and inexpensively constructed.

[Example] Hereinafter, the present invention will be described in detail based on the example shown in the drawings.

First Embodiment FIGS. 1 and 2 illustrate the structure of the main parts of an inkjet printer according to a first embodiment of the present invention. The printer of this embodiment uses the driving force of one motor to drive the paper feeding mechanism that feeds the recording paper, the auto sheet feeder that automatically feeds the recording paper, and the recovery device described above. A driving force switching mechanism is provided to perform the switching. FIGS. 1 and 2 show the driving force switching mechanism and its surrounding structures.

In FIGS. 1 and 2, reference numeral 1 denotes a recording head configured as an ink jet head, which is mounted on a carriage 2. As shown in FIG.

The carriage 2 is slidably provided on a sliding shaft 4.4' installed parallel to the platen 5, which also serves as a recording table and a paper feed roller. The carriage 2 has a timing belt 3 stretched between a motor pulley (not shown) and a brake key 77.
or combined.

When the timing heald 3 is driven by the drive of a carriage motor (not shown), the carriage 2 moves along the platen 5 as shown by arrows a and b to perform recording scanning. That is, as the carriage 2 moves in direction a or b, a print data signal is applied to the print head 1 via the flexible cable 6, and the print head 1 is driven according to the print data to emit ink droplets from its nozzles. The ink is ejected and recorded on a recording sheet (not shown) on a platen S in a dot matrix pattern. −
When the recording of a line is completed, the platen 5 is rotated as shown by arrow C by the drive of the motor (not shown) which is the common driving source mentioned above, and the recording paper is fed upward in FIG. be done.

In the printer of the power tree embodiment, a drive force switching mechanism is provided which mechanically interlocks with the carriage 2 and switches the above-mentioned drive force transmission according to the scanning position of the carriage 2. The mechanism has two differential gear devices 14 that form the main body of the mechanism.
．． 15 and gear cam 8i-1 side plate 9. It is composed of a lock leaf spring 1o and a lock rod 11. The details of these members will be explained below.

First, the gear cam 8 is rotatably provided near the pulley gear 7. The lower half of the gear cam 8 is a gear part 8b, and the gear part 7 provided in the lower half of the pulley gear 7
It is designed to mesh with a. However, as shown in FIG. 2, two portions of the gear portion 8b are toothless portions 8c. Further, in the upper half of the gear cam 8, a narrow V-shaped groove 8a and a wide V-shaped groove 8d are formed.

Further, as shown in FIG. 2, an eccentric cam 8g having a circular cross-section is protruded from the lower surface of the gear cam 8.

Next, the shield plate 9 is provided near the gear cam 8, and fits into and engages with the groove 8d of the gear cam 8 depending on the rotational position of the gear cam 8 or the V-shaped protrusion 9a formed at its tip. It has become.

A lock plate spring 10 is also provided near the gear cam 8, and a small V-shaped protrusion 10a formed in the middle part of the lock plate spring 10 is provided near the gear cam 8.
The gear cam 80 fits into and engages with the groove 8a of the gear cam 8 depending on the rotational position of the gear cam 80. Also, lock plate spring 10
The leading end 10b of the carriage 2 is bent into a trapezoidal shape.
moves in the direction a and reaches a predetermined position at the left end in the figure, the tip 10b of the lock plate 10 comes into contact with the front of the carriage 2, and is pressed, causing the lock plate 10 to move to the rear in Figure 1. It is designed to bend to the side.

Next, the lock rod 11 is used to selectively lock or unlock each gear of a differential gear device 14, 15, which will be described later, in order to switch the transmission of driving force. The lock rod 11 is provided movably in directions a and b in the B movement direction of the carriage in the vicinity of the differential gear device 14.15.
Further, the lock bar 11 is formed in the shape of a key as a whole,
The left end portion 11h in FIG. 2 is formed into a rectangular plate shape.

A long hole 11j is formed in this left end portion 11h, and a single-centered cam 8g of the gear cam 8 is connected to this long hole 11j.
are slidably engaged.

Also, on the portion of the lock rod 11 facing the differential gear device 14.15, there is a protrusion 11a for engaging with each gear of the differential gear device 14.15 and locking them.

11c, lie, llk, and 11m are formed.

Four parts 11b, lid between these protrusions.

11f and IIfl are the parts for unlocking.

Next, the differential gear device 14, 15 transfers rotational driving force input via the gear 13 from a motor, which is a common driving source (not shown), to the gears 16, 17, . The information is transmitted by switching to either IB. The rotational driving force output from the gear 16 is used, for example, as driving force for an auto seat tweeter.

Further, the driving force output from the gear 17 is used as the driving force for the above-mentioned recovery device. Further, the rotational driving force output from the gear 18 is transmitted to the drive system of the paper feeding mechanism including the platen 5 via the gear 19.

The differential gear device 14 has a gear 14a meshed with the gear 13.
, small bevel gears 14b and 14c rotatably attached to gear 14a, and large bevel gears 14d and 14e that mesh with these. And bevel gear 1
4d and 14e are output gears.

Teeth are also formed on the right side of the bevel gear 14d in FIG. 2, and the gear 18 is meshed with these teeth. Further, the outer peripheral portions of the bevel gears +46 and 14e are formed as spur gears. The gear 14a and the bevel gear 14d are the bevel gear 14e.
It is rotatably supported on a rotating shaft 14f.

The rotating shaft 14 of this bevel gear 14e. f is the rotating shaft 15g for inputting the rotational driving force of the differential gear device 15;
is directly connected to the differential gear unit 14.15.
are connected in series such that the output of the differential gear device 14 becomes the input of the differential gear device 15.

The differential gear device 15 is composed of a rotating body 15a integrally formed with a rotating shaft 15g, two small bevel gears 15b and +5c rotatably mounted on the rotating body 15a, and a large bevel gear 15d15e that meshes with the rotating body 15a. has been done. The bevel gears 15d and +5e are rotatably supported by rotation 4111115g. Bevel gears 15d, 15e
The outer periphery of is a spur gear, and gears 16 and 17 are meshed with each of the spur gears.

Furthermore, the integral rotating shaft 14f of the differential gear device 14.15
, 15g are rotatably supported by bearings at both ends of the frame 2425 of the printer. A positioning spring 26 is mounted between the frame 24 and the gear 18 so as to wrap around the right end of the rotation shaft in FIG.

This spring 26 pushes the differential gear device 14, 15 to the left side in the figure and positions it. Further, the pressure of the spring 26 causes the gear 18 and the bevel gear 14d to mesh with each other.

Next, the switching operation of driving force transmission by the driving force switching mechanism having the above configuration will be explained.

First, in the state shown in FIGS. 1 and 2, the biasing leaf spring 9
The protrusion 9a fits into the groove 8d of the gear cam 8 and presses the inner surface of the groove 8d on the back side in FIG.
is biased clockwise in the figure, but the lock plate 10
Since the protrusion 10a is engaged with the groove 8a, rotation of the gear cam 8 in the clockwise direction is prevented. Also, in this state, as shown in FIG. 2, the toothless portion 8C of the gear cam 8 faces the gear portion 7a of the pulley gear 7, and the pulley gear 7 rotates as the carriage 2 moves for recording scanning. Even if the rotational force is not transmitted to the gear cam 8, the gear cam 8 does not rotate.

In this state, as shown in FIG. 2, the protrusions 11a, 11c, and llk of the lock rod 11 engage to lock the bevel gears 15e, 15d of the differential gear device 15 and the bevel gear +4e of the differential gear device 14. When the rotational driving force of a motor, which is a common driving source (not shown), is transmitted to the gear 13, only the bevel gear 14d is rotated by the driving force, and the driving force is transmitted through the gears 18 and 19. The signal is transmitted to the paper feeding mechanism including the platen 5, the platen 5 rotates in the C direction, and the paper is fed. That is, in this state, the control section of the printer drives the motor as necessary to feed the paper.

Next, the carriage 2 is moved in the C direction from the above state,
When the carriage 2 reaches the predetermined position on the left end in Figure 1,
comes into contact with and suppresses the front end tob of the lock leaf spring 10, thereby causing the lock leaf spring 10 to swing toward the back in FIG. 1 and disengage the projection 10a from the groove 8a. As a result, the gear cam 8 is slightly rotated clockwise in the figure by the urging force of the leaf spring 9. Then, the teeth 8f on the right side edge of the toothless portion 8C of the gear cam 8 shown in FIG. By rotating in the direction, gear cam 8
is rotated clockwise. The eccentric cam 8g moves along with the rotation, and the lock s11 is moved in the C direction. That is, after the teeth 8f of the gear cam 8 are engaged with the gear portion 7a of the pulley gear 7, the lock rod 11 is moved in the direction a in conjunction with the movement of the carriage 2 in the direction a.

Then, when the lock rod 11 moves in conjunction with the carriage 2 from the state shown in FIG. 2 in the direction a by a distance slightly larger than the width of the protrusion 11c, Ilk, the bevel gear 15e remains locked by the protrusion 11a. Bevel gear 15d
, 14e are the recesses 11d, 11. It faces Q and is locked or unlocked.

Further, the bevel gear 14d is locked by the protrusion 11m.

In this state, when a rotational driving force is input from the gear 13, the bevel gear 14e and the rotating body 15a integrated therewith are rotated, and the bevel gear 15d is also rotated.
Rotational driving force is transmitted to gear 16.

This rotational driving force drives, for example, an auto sheet feeder.

Furthermore, when the lock rod 11 moves a little in the direction a in conjunction with the movement of the carriage 2 in the direction a from the above state, the bevel gear 15e faces the recess 11b and the lock is released.

The bevel gear 15d is locked by the protrusion 1ie. The bevel gear 14e remains in the unlocked state while facing the four parts 11. Further, the bevel gear +4d remains engaged with the protrusion 11m and remains in a locked state. In this state, when driving force is input from the gear 13, the driving force causes the bevel gear 14e to
and the rotating body 15a integrated therewith is rotated, and the bevel gear 1
5e is rotated, and the driving force is transmitted to the gear 17. This driving force drives, for example, the recovery device described above.

Note that when the carriage 2 is moved in the direction b from this state, the lock rod 11 is moved in the direction b in conjunction with this, and the driving force is switched in the reverse order to the above. Then, in conjunction with the movement of the carriage 2 in the b direction, the gear cam 8 sequentially rotates counterclockwise in FIG. At the same time, the carriage 2 moves away from the front end 10b of the lock plate spring 10, and the lock plate spring 1o returns to the front, and its protrusion 10a engages with the groove 8a of the gear cam 8, and the gear cam 8 is locked. , return to the initial state.

As described above, the driving force switching mechanism of the printer of this embodiment mechanically interlocks with the carriage 2 and switches the driving force transmission according to the position of the carriage 2. By selecting the position of the carriage 2, the driving force inputted through the gear 13 from a motor of a common driving source (not shown) can be selectively transmitted to one of the gears 16 to 18.

According to this embodiment, the driving force can be switched easily and accurately by selectively locking or unlocking each output gear of the differential gear device 14, 15 via the lock rod 11 as described above. It's done smoothly. In other words, in a differential gear system, each gear is always in mesh with each other, and the meshing of the gears is not changed as in the conventional example described above in order to change the driving force, so there is no problem associated with switching the meshing. . Further, unlike the conventional example, the structure does not become complicated in order to achieve smooth engagement, and the switching mechanism can be constructed at low cost.

Further, by connecting a plurality of differential gear devices in series as in this embodiment, a driving force switching mechanism capable of performing multi-stage switching can be constructed easily and inexpensively. In the embodiment, two differential gear devices are connected to perform three-stage switching, or by increasing the number of connected devices, even more multi-stage switching can be performed. The number of devices to be connected is n
In this case, switching can be performed in n+1 stages.

Second Embodiment Although the differential gear devices 14 and 15 constituting the driving force switching mechanism of the above embodiment were constructed from bevel gears, as shown in FIG. 3 as a second embodiment of the present invention, It is also possible for both devices 14,15 to consist only of spur gears. Each gear constituting the differential gear device 14, 15 in FIG. 3 is indicated by the same reference numeral and dash as the corresponding gear in FIGS. 1 and 2. Both devices 14.15
The configuration and operation of the meshing relationship of each gear are shown in Figure 1.
Since it corresponds to that in FIG. 2, its explanation will be omitted. Third
Even with the configuration as shown in the figure, the same effect as described above can be obtained.

[Effects of the Invention] As is clear from the above description, according to the present invention, in a printing apparatus that performs printing scanning by moving a carriage on which a printing head is mounted eight times, one It has a driving force switching mechanism that switches and transmits the driving force of two drive sources, and the switching mechanism is composed of a plurality of differential gear devices, and the plurality of differential gear devices are configured such that the output of the preceding device is transmitted to the subsequent device. Since we have adopted a structure in which the driving force is connected in series to serve as the input, the driving force switching mechanism can be easily and inexpensively implemented, and the switching of multi-stage driving force transmission can be performed accurately and smoothly. By using one drive source in common for a plurality of drive mechanisms, an excellent effect can be obtained in that the recording apparatus can be significantly reduced in cost and size.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the structure around the driving force switching mechanism of a printer according to an embodiment of the present invention, FIG. 2 is a partially cutaway plan view showing the surroundings of the switching mechanism, and FIG. FIG. 4 is a sectional view showing the structure of a differential gear device constituting a driving force switching mechanism of a printer according to a second embodiment, and FIG. 4 is a perspective view illustrating a conventional printer. 1... Recording head 2... Carriage 3...
Timing belt 4.4'...Sliding shaft 5...Platen 6...Flexible cable 7...Pulley gear 8...Gear cam 9...Biasing leaf spring 10...
・Lock plate 13.16-19...Gear 14.15...Differential gear device

Claims (1)

[Claims] 1) In a printing apparatus that performs printing scanning by moving a carriage on which a printing head is mounted, a drive that switches and transmits the driving force of one drive source to a plurality of drive mechanisms in the printing apparatus. It has a force switching mechanism, and the switching mechanism is composed of a plurality of differential gear devices, and the plurality of differential gear devices are connected in series so that the output of the device in the preceding stage becomes the input to the device in the succeeding stage. A recording device characterized by: 2) The record according to claim 1, characterized in that in the plurality of differential gear devices, the output rotation shaft of the differential rotation output of one of the devices at the front stage is directly connected to the input rotation shaft of the device at the rear stage. Device. 3) The driving force transmission is switched by selectively locking or unlocking each of the rotation output gears of the plurality of differential gear devices. Recording device.