JP6040657B2 - Liquid ejecting apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a liquid discharge apparatus and an image forming apparatus, and more particularly to a pump drive mechanism.

  As is well known, a printer, a facsimile machine, a copying machine, and an image forming apparatus provided with a combination of these functions include a liquid ejection apparatus having a recording head composed of a liquid ejection head that ejects liquid droplets such as ink. The configuration used is known.

In a liquid ejection apparatus, an image is formed by adhering or penetrating droplets ejected from a recording head while conveying a recording medium such as recording paper.
The target of the recording medium includes not only the recording paper described above but also a material capable of adhering or penetrating liquids such as fibers such as intention, leather and metal, resin, glass, wood and ceramics.

  In an image forming apparatus provided with a liquid discharge device, in order to stabilize the ink discharge operation from the liquid discharge head, the ink in the liquid discharge head is maintained at a predetermined negative pressure (acts on the ink in the liquid discharge head). It is important to keep the pressure to be a predetermined negative pressure). For this reason, in general, an ink supply system that supplies ink to the liquid discharge head is provided with a negative pressure generating means, and ink to which negative pressure is applied by the negative pressure generating means is supplied to the liquid discharge head.

  As such a negative pressure generating means, a configuration in which a negative pressure is formed by utilizing the capillary phenomenon of a sponge-like ink absorber housed in the ink tank, or an ink tank so as to maintain the negative pressure in the ink tank There has been known a configuration provided with a biasing means such as a spring for biasing a flexible member forming at least a part of the ink cartridge outwardly of the ink tank. Further, as another negative pressure generating means, there is also known a configuration in which an ink tank is disposed below the liquid discharge head and a negative pressure is applied to the ink using a water head difference.

On the other hand, liquids such as ink filled in the nozzles may thicken and harden when dried, or bubbles may be included in the liquid.
Such a phenomenon hinders normal discharge of the liquid, and it is known to provide a maintenance / recovery device for maintaining and recovering the function of the nozzle.
The maintenance / recovery device is known to include a cap unit that covers and moisturizes the nozzle and a unit that sucks the inside of the nozzle and collects the thickened liquid in the nozzle in a waste liquid tank.

By the way, in the case of using liquids of a plurality of colors in the liquid ejection device, not only a liquid supply pump is required for each color liquid supply path, but also one of the driven parts used in the maintenance and recovery device for the nozzles. This suction pump is also required for each nozzle.
For this reason, there exists a possibility of causing the enlargement and complexity of a structure for the reason of installing the drive source which drives many pumps.

  Therefore, a single drive source for driving the planetary gear mechanism is provided in the drive path of each pump, and a selection drive mechanism for setting the pump selection and the liquid supply state and the pump pause state according to the drive direction switching of the drive source A configuration with the above has been proposed. (For example, patent document 1).

  In Patent Document 1, three or more pumps that transfer ink in three or more ink paths, a single drive source that drives the pump, and a drive target by rotational power in the first direction input from the drive source are disclosed. An ink jet printer having a selection drive mechanism that drives a pump selected by rotational power in a second direction input from a drive source while the pump is selected is described.

  The selective drive mechanism included in the ink jet printer has a sun gear that rotates in a first direction and a second direction when rotational power is input, revolves around the sun gear according to the rotation of the sun gear, and In a state where the revolution is restricted, the planetary gear that rotates according to the rotation of the sun gear, and the planetary gear revolves so that the planetary gear sequentially meshes with the planetary gear when the planetary gear revolves according to the first direction rotation of the sun gear. Revolution restricting means is provided for restricting the revolution of the planetary gear according to the second direction rotation of the pump drive gear and the sun gear of the pump arranged along the meshing position with the pump drive gear.

  In the driving device described in Patent Document 1, the sun gear is rotated in the second direction after the planetary gear is revolved (pump selection operation) to the meshing position of the pump drive gear to be driven by the rotation of the sun gear in the first direction. In this case, the planetary gear whose revolution is restricted rotates in a state of meshing with the pump drive gear, and the pump drive gear is driven to rotate forward (pump drive operation). In this configuration, the drive output gear is a sun gear, the driven part is a pump, the drive input gear is a pump drive gear, and the drive transmission gear is a planetary gear.

  In addition, in the driving device described in Patent Document 1, a release planet is provided separately from the planetary gear and the planetary lever described above in order to input rotational drive in the opposite direction to the pump driving operation described above. A gear and a release planetary lever are provided, and a drive transmission path using a release planetary gear and a release planetary lever different from the drive transmission path using the planetary gear and the planetary lever is formed.

  By forming such a drive transmission path, the release planetary gear and the planetary gear while the planetary gear revolves (pump selection operation) to the meshing position of the pump drive gear to be driven by the first rotation of the sun gear. Through the drive transmission path using the release planetary lever, rotational drive in the reverse direction is input to all the pumps in the above-described pump drive operation.

  In the configuration described in Patent Document 1, it is possible to transmit drive to each driven unit by a smaller number of drive sources than the driven units, and it is necessary to provide a moving mechanism for each of the plurality of drive transmission gears. Therefore, it is possible to solve the problems of increasing the size and cost of the apparatus.

  However, in the configuration described in Patent Document 1, when the release planetary gear revolves according to the second direction rotation of the sun gear, the release planetary lever hits the stopper, and the revolution does not mesh with the pump drive gear. It is regulated by. For this reason, only one-way rotational drive can be transmitted to the driven part. As a result, the degree of freedom of operation decreases.

In the configuration described in Patent Document 1, rotational driving in the direction opposite to the one direction can be transmitted to the driven part by rotation of the sun gear in the first direction.
However, the drive transmission through the drive transmission path using the release planetary gear and the release planetary lever transmits the drive to all of the plurality of driven parts at the same time. Therefore, rotational drive transmission in both forward and reverse directions cannot be performed.

  An object of the present invention is to reduce the size of the apparatus by reducing the number of driving sources used in the above-described conventional liquid ejecting apparatus from the number of driven parts, and without being restricted by the operation of the driving mechanism. Another object of the present invention is to provide a liquid ejection apparatus and an image forming apparatus having a configuration capable of freely transmitting rotational driving in both forward and reverse directions with respect to a driving force transmission path to a selected driven part.

In order to achieve this object, the present invention comprises a plurality of ejection heads that eject different types of droplets,
A plurality of head tanks for supplying different types of liquid to the plurality of ejection heads;
A plurality of liquid main tanks for supplying different types of liquid to the plurality of head tanks;
A plurality of liquid feed pumps for sending liquid from each of the plurality of liquid main tanks to the plurality of head tanks, and reversely feeding the liquid from the plurality of head tanks to the plurality of liquid main tanks;
A single drive source for driving the plurality of liquid feeding pumps, capable of rotating in both directions of a first direction and a second direction opposite to the first direction;
A drive switching mechanism that selects which of the plurality of liquid feeding pumps is driven by rotating the single drive source in the first direction;
A rotation direction switching mechanism for switching the rotation direction of the liquid feed pump with respect to the liquid feed pump selected by the drive switching mechanism by rotating the single drive source in the first direction;
By rotating the single drive source in the second direction, the rotational driving force is transmitted in the rotational direction switched by the rotational direction switching mechanism to the liquid feed pump selected by the drive switching mechanism. A rotational driving force transmission mechanism;
Arranged in a first driving force transmission path from the single driving source to the driving switching mechanism, and only the rotational driving force in the first direction is switched from the single driving source to the driving switching mechanism and the rotational direction. A first clutch that transmits to the mechanism;
It is arranged in a second driving force transmission path from the single driving source to the rotational driving force transmission mechanism, and only the rotational driving force in the second direction is transferred from the single driving source to the rotational driving force transmission mechanism. A second clutch to transmit,
A liquid ejection apparatus comprising:

According to the present invention, when driving a plurality of liquid feeding pumps that feed and reverse the liquid between a plurality of liquid main tanks and a plurality of head tanks by a single driving source, the single drive A first clutch that transmits only the driving force when the source is driven in the first direction, and a second clutch that transmits only the driving force when the single drive source is driven in the second direction And are provided.
As a result, the selection of the liquid feeding pump, the selection of liquid feeding or reverse feeding according to the rotation direction of the selected liquid feeding pump, and the transmission of the driving force to the selected liquid feeding pump are performed by the clutch described above. Can be selected by control. As a result, it is possible to set the drive state of each liquid feed pump without providing a drive source for each of the plurality of liquid feed pumps and without restricting the rotation direction such as rotation in only one direction.

1 is an external view of an image forming apparatus using a liquid ejection apparatus according to an embodiment of the present invention. FIG. 2 is a schematic diagram for explaining an internal configuration of the image forming apparatus illustrated in FIG. 1. FIG. 3 is a plan view of the internal configuration shown in FIG. 2. FIG. 2 is an external view illustrating a configuration of a head unit used in the liquid ejection device illustrated in FIG. 1. It is a schematic diagram which shows the liquid supply path | route used for the liquid discharge apparatus shown in FIG. It is a schematic diagram for demonstrating the drive structure of the pump used for the liquid discharge apparatus shown in FIG. FIG. 2 is a schematic diagram for explaining an example of a drive switching mechanism used in the liquid ejection device shown in FIG. 1. It is a schematic diagram for demonstrating the structure of a rotation direction switching mechanism column and a driving force transmission mechanism among the drive mechanisms used for the liquid discharge apparatus shown in FIG. It is a figure for demonstrating the rotation angle of the rotation direction switching cam used for the rotation direction switching mechanism shown in FIG. FIG. 10 is a timing chart for explaining pump selection timing based on the rotation angle shown in FIG. 9 and normal rotation and reverse rotation timing of the selected pump. FIG. 9 is a schematic diagram for explaining a drive transmission path based on the configuration shown in FIGS. 7 and 8. It is a figure for demonstrating the modification about the drive switching mechanism shown in FIG. FIG. 12 is a diagram for explaining yet another modification of the drive switching mechanism shown in FIG. 11. It is a schematic diagram for demonstrating an example of the pump used for the liquid discharge apparatus shown in FIG.

The best mode for carrying out the present invention will be described below with reference to the drawings.
FIG. 1 is an external view of an image forming apparatus using a night liquid ejecting apparatus according to the present invention.
The image forming apparatus shown in FIG. 1 has a paper feed tray 2 for loading paper loaded in the apparatus main body 1 and a sheet on which an image is recorded (formed) detachably mounted on the apparatus main body 1. A paper discharge tray 3 for stocking is provided.
Furthermore, a cartridge loading unit for loading an ink cartridge that protrudes from the front surface to the front side of the apparatus main body 1 and is lower than the upper surface is provided at one end of the front surface of the apparatus main body 1 (side of the paper supply / discharge tray section). 4 is provided, and the upper surface of the cartridge loading unit 4 is configured as an operation / display unit 5 provided with operation buttons, a display, and the like.

  The cartridge loading unit 4 is used as a plurality of main tanks containing inks that are different color materials, for example, black (K) ink, cyan (C) ink, magenta (M) ink, and yellow (Y) ink. Ink cartridges 10k, 10c, 10m, and 10y (referred to as “ink cartridge 10” when colors are not distinguished) are inserted from the front side to the rear side of the apparatus main body 1 and can be loaded. A front cover (cartridge cover) 6 that is opened when the ink cartridge 10 is attached / detached is provided on the front side of 4 to be openable and closable.

Next, the mechanism part of this liquid discharge apparatus will be described with reference to FIGS. 2 is a schematic side view illustrating the outline of the mechanism, and FIG. 3 is an explanatory plan view of the main part.
In FIG. 3, a carriage 33 is slidably held in a main scanning direction by a guide rod 31 which is a guide member horizontally mounted on the left and right side plates 21A and 21B and a stay 32, and a timing belt is interposed by a main scanning motor (not shown). In FIG. 3, the scanning is moved in the direction indicated by the arrow (carriage main scanning direction).

  The carriage 33 has liquid ejection heads 34a, 34b, 34c, 34d for ejecting ink droplets of each color of yellow (Y), cyan (C), magenta (M), and black (K). A liquid discharge head 34 ") is provided. The liquid ejection head 34 is mounted with a nozzle row composed of a plurality of nozzles arranged in the sub-scanning direction orthogonal to the main scanning direction and the ink droplet ejection direction facing downward.

  As an ink jet head constituting the liquid discharge head 34, a piezoelectric actuator such as a piezoelectric element, a thermal actuator that utilizes a phase change caused by liquid film boiling using an electrothermal transducer such as a heating resistor, and a metal phase change caused by a temperature change. A shape memory alloy actuator using an electrostatic force, an electrostatic actuator using an electrostatic force, and the like provided as pressure generating means for generating a pressure for discharging a droplet can be used.

The carriage 33 has head tanks 35k, 35c, 35m, and 35y as liquid storage containers that supply ink of each color corresponding to the nozzle rows of the liquid discharge head 34 (referred to as “head tank 35” when not distinguished). ) Is installed. As described above, the head tank 35 is supplied with ink of each color from the ink cartridge 10 of each color mounted in the cartridge loading unit 4 via the ink supply tube 36 of each color. In FIG. 3, reference numeral 36 a indicates a suction flow path at the time of idle driving, and communicates with a waste liquid tank (not shown).
The cartridge loading unit 4 is provided with a liquid feed pump unit 24 for feeding ink in the ink cartridge 10.

  On the other hand, as shown in FIG. 2, the sheets 42 are separated one by one from the sheet stacking section 41 as a sheet feeding section for feeding the sheets 42 stacked on the sheet stacking section (pressure plate) 41 of the sheet feeding tray 2. A half-moon roller (sheet feeding roller) 43 to be fed and a separation pad 44 made of a material having a large friction coefficient disposed opposite to the sheet feeding roller 43 are provided. The separation pad 44 is attached to the sheet feeding roller 43 side. It is energized.

  A holding member having a guide member 45 for guiding the paper 42, a counter roller 46, a conveyance guide member 47, and a tip pressure roller 49 for feeding the paper 42 fed from the paper feeding unit to the lower side of the liquid discharge head 34. A member 48 is provided, and a transport belt 51 is provided as a transport unit for electrostatically attracting the fed paper 42 and transporting it at a position facing the liquid discharge head 34.

The conveyor belt 51 is an endless belt, and is configured to wrap around the conveyor roller 52 and the tension roller 53 and circulate in the belt conveyance direction (sub-scanning direction). Further, a charging roller 56 that is a charging unit for charging the surface of the transport belt 51 is provided.
The charging roller 56 is disposed so as to come into contact with the surface layer of the transport belt 51 and to rotate following the rotation of the transport belt 51.
The conveyance belt 51 can be moved in the belt conveyance direction of FIG. 3 by rotating the conveyance roller 52 through a timing by a sub-scanning motor (not shown).

  As a paper discharge unit for discharging the paper 42 recorded by the liquid discharge head 34, a separation claw 27 for separating the paper 42 from the transport belt 51, a paper discharge roller 61, and a paper discharge roller 62 are provided. A paper discharge tray 3 is provided below the paper roller 62.

A duplex unit 71 is detachably mounted on the back surface of the apparatus body 1.
The duplex unit 71 takes in the paper 42 returned by the reverse rotation of the transport belt 51, reverses it, and feeds it again between the counter roller 46 and the transport belt 51. Further, the upper surface of the duplex unit 71 is used as a manual feed tray 72.

  As shown in FIG. 3, a maintenance / recovery mechanism 81 including a recovery means for maintaining and recovering the nozzle state of the liquid ejection head 34 is disposed in the non-printing area on one side of the carriage 33 in the scanning direction. .

  The maintenance / recovery mechanism 81 includes cap members for capping each nozzle surface of the liquid discharge head 34 (collectively indicated by reference numeral 82), a wiper blade 83 which is a blade member for wiping the nozzle surface, and In order to discharge the thickened ink, there is provided an empty discharge receiver 84 for receiving droplets when performing empty discharge for discharging droplets that do not contribute to recording.

  As shown in FIG. 3, in the non-printing area on the other side in the scanning direction of the carriage 33, the liquid used when performing the idle ejection for ejecting the liquid droplets that do not contribute to the recording in order to discharge the ink that has been thickened during the recording or the like An empty discharge receiver 88 for receiving droplets is disposed, and the empty discharge receiver 88 is provided with an opening along the nozzle row direction of the liquid discharge head 34 (generally indicated by reference numeral 89 for convenience).

In such an ink liquid ejecting apparatus, printing is performed on the paper 42 by the following procedure.
The sheets 42 are separated and fed one by one from the sheet feeding tray 2, and the sheet 42 fed substantially vertically upward is guided by the guide member 45 and sandwiched between the transport belt 51 and the counter roller 46 and transported. The Following this, the leading edge of the paper 42 is guided by the conveying guide member 47 and pressed against the conveying belt 51 by the leading pressure roller 49, and the conveying direction is changed by approximately 90 °.

  At this time, a positive output and a negative output are alternately repeated with respect to the charging roller 56, that is, an alternating voltage is applied, and a charging voltage pattern in which the conveying belt 51 alternates, that is, in a sub-scanning direction that is a circumferential direction. , Plus and minus are alternately charged in a band shape with a predetermined width. When the paper 42 is fed onto the conveyance belt 51 charged alternately with plus and minus, the paper 42 is attracted to the conveyance belt 51, and the paper 42 is conveyed in the sub-scanning direction by the circular movement of the conveyance belt 51.

  In the process of moving the carriage 33, the liquid ejection head 34 is driven in accordance with the image signal, thereby ejecting ink droplets onto the stopped paper 42 to record one line. The next line is recorded. Based on the recording end signal or the signal that the trailing edge of the paper 42 reaches the recording area, the recording operation is finished, and the paper 42 is discharged onto the paper discharge tray 3.

  Further, the carriage 33 moves to the maintenance / recovery mechanism 81 side during printing (recording) standby. When the carriage 33 moves to the maintenance / recovery mechanism 81, the liquid ejection head 34 is capped by the caps 82 (a to d), and the ejection failure due to ink drying is prevented by keeping the nozzle in a wet state. In addition, the ink is sucked from the nozzle by a suction pump (not shown) with the liquid ejection head 34 capped by the cap 82 (referred to as “nozzle suction” or “head suction”), and the recovery operation for discharging the thickened ink and bubbles. Is done. In addition, an idle ejection operation for ejecting ink not related to the recording is performed before the start of recording or during the recording. Thereby, the stable discharge performance of the liquid discharge head 34 is maintained.

FIG. 4 shows a liquid discharge head unit used in the image forming apparatus.
In FIG. 4, the liquid discharge head unit supplies the recording liquids of the same color or different colors to the four nozzle rows of one liquid discharge head 34, and between the head tank 35 and the head tank 35 and the liquid discharge head 34. The filter unit 35A is interposed. Further, from the liquid discharge head 34, although not shown, a flexible cable for transmitting a signal for driving the actuator means of the liquid discharge head 34 is drawn out.

The head tank 35 is formed with an ink storage portion which is a recording liquid storage portion on both sides of the tank main body 35B. Although not shown in detail, a flexible film-like member (possible to the opening of these ink storage portions). A flexible film-like member) is adhered and sealed by adhesion or welding.
A spring (spring: not shown), which is an elastic member for urging the film-like member (not shown) outward, is provided between the tank body 35B and the film-like member inside the ink containing portion. These film-like members and elastic members constitute a negative pressure generating mechanism. Further, a negative pressure detection lever 35C that is displaced in accordance with the displacement of the film-like member is mounted on the tank body 35B so as to be swingable.

At the upper part of the tank main body 35B, an air opening / closing mechanism 37 is provided as a pressure control means for opening and closing an air opening passage provided to open the ink containing portion to the air.
The air opening / closing mechanism 37 uses an opening / closing valve capable of communicating or blocking between the ink container and the atmosphere, and is opened when the air accumulated in the ink container is discharged to the outside. The opening / closing operation of the opening / closing valve is performed when it is pressed by an actuator (not shown).

  The tank main body 35B is formed with an ink supply port portion 38 for supplying ink to the ink storage portion. The ink supply port portion 38 is connected to a tube indicated by reference numeral 36 in FIG. .

The characteristics of the present embodiment will be described as follows with the above configuration as an object.
A feature of this embodiment is that the first that can transmit the rotation of the drive source in either the first or second direction to the transmission path through which the driving force is transmitted from the single drive source to the plurality of pumps. The second clutch, specifically, the one-way clutch is arranged.
In particular, when the first and second clutches are used to rotate in the first direction with the drive source, the drive switching corresponding to the selection of the pump and the switching of the rotation direction with the pump (in the liquid feeding direction or the reverse feeding direction). And a driving force is transmitted to the selected pump when the driving source is rotated in the second direction.

Before describing this feature, a premise configuration to which this feature is applied will be described below.
In the present embodiment, transmission control of the driving force transmitted from the driving source is performed for the liquid feeding pump P1 provided in the liquid supply path from the ink cartridge 10 to the head tank 35. FIG. 5 shows one of the liquid supply paths provided for each of a plurality of types of colors.

In FIG. 5, a supply channel 103 (hereinafter also referred to as a tube 103 for convenience) provided with a tube is provided in a liquid supply path from the ink cartridge 10 to the head tank 35.
The liquid feed pump P <b> 1 is used to send liquid ink to the head tank 35.

The liquid feed pump P1 is a member that can rotate in forward and reverse directions corresponding to the first and second rotational directions. The liquid feed pump P1 can perform liquid feed to the head tank 35 and reverse feed of ink from the head tank 35 toward the ink cartridge 10 in accordance with the selected driving direction, so-called return. Yes.
When the ink is returned from the head tank 35 to the ink cartridge 10, the pressure in the head tank 35 is adjusted. The liquid feed pump P1 is disposed in the pump unit indicated by reference numeral 24 in FIG.

Here, the drive structure of the liquid feed pump P1 will be described with reference to FIG.
In FIG. 6, the number of liquid feed pumps P <b> 1 corresponding to each head tank 35 is provided, and the drive is performed by a single drive source 105.
For this reason, a common drive gear 106 that meshes with transmission gears 107a to 107d provided for each liquid feed pump P1 is attached to the output shaft of the drive source 105.
Thus, the rotations of the drive gear 106 are transmitted to the transmission gears 107a to 107d all at once, so that each liquid feed pump P1 is uniformly driven. In FIG. 6, thick arrows indicate power transmission paths during forward and reverse rotation.

  In the present embodiment, a drive switching mechanism and a rotation direction switching mechanism are used to select the liquid feed pump P1 and switch the rotation direction.

First, a drive mechanism used for drive switching for selecting the liquid feed pump P1 will be described with reference to FIG.
In FIG. 7, a pump drive device 200 is used as a drive mechanism for the liquid feed pump P1.
The pump drive device 200 includes four liquid feed pumps P1 (for convenience, one of the four liquid feed pumps P1 is shown in FIG. 7).
The liquid feed pump P1 is driven by receiving a rotation drive signal from a pump drive gear 201, which is a drive input gear included in each pump.
In addition to the pump drive gear 201, the pump drive device 200 includes a single rotation drive motor 206 provided as a rotation drive source of the liquid feed pump P1, and forward rotation and reverse rotation used for a rotation direction switching mechanism described later. A common gear 512, a central drive gear 204, idler gears 208 and 502, a switching gear 203, a switching gear swing lever 203b, a circular slit plate 205, a slit driving gear 207, and the like are provided.

  Among the idler gears, the idler gear denoted by reference numeral 208 is a drive gear for the liquid feed pump P1 via the common gear 512 and the central drive gear 204 when the rotary drive motor 206 used as a drive source rotates in the second direction. This is a drive output gear that transmits a driving force to 201.

  Among the idler gears, an idler gear denoted by reference numeral 502 meshes with a slit drive gear 207 used for a drive switching mechanism and a rotation direction switching transmission gear 503 used for a rotation direction switching mechanism, which will be described later. It is a drive output gear that transmits a driving force to each of these gears when rotating in one direction.

  On the other hand, the switching gear 203, the switching gear swing lever 203b, the circular slit plate 205, the slit drive gear 207, and the switching gear swing lever 203b of the switching mechanism 203 are directed to the pump drive gear 201. A switching gear biasing spring (not shown) that biases is used.

Among the members described above, the slit driving gear 207 is a gear that rotates as the driving force of the rotational driving motor 206 is transmitted when the rotational driving motor 206 used as a driving source rotates in the first direction, which will be described later. It is.
The circular slit plate 205 is a member that is integrated with the slit drive gear 207 and rotates in conjunction with the slit drive gear 207.

  As shown in FIG. 7B, the switching gear swing lever 203b is rotatably supported at one end by an idler gear shaft 208a that is a rotating shaft of the idler gear 208, and the switching gear shaft 203a is rotatably supported at the other end. It is a member.

As the circular slit plate 205, a member having a different diameter having a lever swinging direction slit portion 212b formed of a bulging portion in a part of the circumferential direction is used. The circular slit plate 205 rotates around the slit plate rotation shaft 205a with a predetermined direction parallel to a plane orthogonal to the switching gear shaft 203a (a surface parallel to the paper surface shown in FIG. 7B) as a target. be able to.
As a result, all four switching gear shafts 203a are sandwiched between the slits 212 including the circular slit portions 212a that are the moving direction slit portions formed in the shape along the rotational movement direction, and the movement of the switching gear 203 is performed by the slits 212. Can be regulated.
With such a configuration, the moving range and moving direction (the direction indicated by the arrow FR in FIG. 7B) of the switching gear shaft 203a are restricted on the circumference around the idler gear shaft 208a.

On the other hand, as shown in FIG. 7C, a peripheral portion having the same diameter along the circumferential direction is used as the lever swinging direction slit portion 212b formed of the bulging portion of the circular slit plate 205.
The peripheral portion engages with the time for which the switching gear 203 and the pump drive gear 201 rotate while the switching gear shaft 203a is sandwiched, and the forward and reverse gears in the rotation direction switching mechanism described later. Corresponds to a region where a time for meshing with the gear transmitting the driving force during forward and reverse rotations is ensured (in FIG. 7, for the sake of convenience, it is indicated as a gear meshing rotation time region).

  The circular slit plate 205 is a drive transmission position where the driving force can be transmitted to the drive gear 201 by utilizing the action of restricting the moving range and moving direction of the switching gear shaft 203a on the circumference around the idler gear shaft 208a. And the switching gear shaft 203a can be moved between the driving non-transmission position where the transmission of the driving force becomes impossible.

At the drive transmission position, the switching gear 203 meshes with both the drive gear 201 and the idler gear 208, and the driving force from the idler gear 208 is transmitted to the drive gear 201 to drive the liquid feed pump P1.
On the other hand, in the drive non-transmission position, the meshing is released when the switching gear 203 is separated from the drive gear 201, and the drive force is not transmitted from the idler gear 208.

In the present embodiment, the positioning of the switching gear 203 to the drive transmission position and the drive non-transmission position is determined according to the rotation direction of the rotary drive motor 206.
Specifically, when the rotational drive motor 206 rotates in the first direction, the switching gear 203 is selected when the switching gear shaft 203a to be selected moves toward the lever swinging direction slit 212b forming the bulging portion. It meshes with both the drive gear 201 and the idler gear 208 on the target liquid feed pump P1 side.
On the other hand, the switching gear 203 facing the liquid feed pump P1 that is not selected is separated from the driving gear 201 and released from meshing when the switching gear shaft 203a enters the circular slit portion 212a of the circular slit plate 205.

When the switching gear 203 is positioned at the drive transmission position, the rotation direction of the liquid feed pump P1 is switched by the rotation direction switching mechanism.
The switching of the rotation direction corresponds to the forward rotation and the reverse rotation switching of the liquid feed pump P1. This switching is performed while the peripheral portion of the lever swinging direction slit portion 212b formed by the bulging portion of the circular slit plate 205 shown in FIG. 7 is moved, and the liquid feeding pump P1 is rotationally driven in the switched direction. The

FIG. 8 is a schematic diagram for explaining the rotation direction switching mechanism.
This figure shows a drive transmission path using a rotational direction switching transmission gear indicated by reference numeral 503 in FIG. 7 starting from a rotational drive motor 206 used as a single drive source.

In FIG. 8, rotation direction switching cam gears 504a and 504b, a sliding gear 505, and a sliding rod 506 are used for the rotation direction switching mechanism.
The rotation direction switching cam gears 504a and 504b are gears that are linked to the rotation direction switching transmission gear 503 that meshes with the idler gear 502 shown in FIG.
In FIG. 8, the rotational direction switching cam gears 504a and 504b are provided with rotational direction switching cams 504c coaxially integrated with the rotational direction switching cam gears 504a and 504b on opposite end surfaces.

The rotation direction switching cam 504c is a cam having a cam profile formed with a protrusion along the left-right direction of the paper surface shown in FIG.
The relative phases of the protrusions are deviated by 1/4 × 1/2 in the rotation direction. In this case, ¼ is a selection cycle of four pumps, and ½ is a normal rotation and reverse rotation cycle in a selection period (1/4) of one pump.

FIG. 9 shows the rotation angle of the rotation direction switching cam 504c described above, and FIG. 10 shows the selection timing of the liquid feed pump P1 and the forward and reverse operations of the selected liquid feed pump P1 according to the rotation angle shown in FIG. It is a figure which shows the timing of.
FIG. 9 shows the rotation angle of the rotation direction switching cam 504c in the case of four liquid feed pumps P1, and each liquid feed pump P1 is selected in four division periods of one rotation of the rotation drive motor 206, and each division is performed. A rotation angle that is half of the cycle is set as the forward rotation and reverse rotation timing.

By setting the rotation angle as described above, as shown in FIG. 10, each liquid feed pump P <b> 1 performs forward rotation and reverse rotation at a half cycle of the selected time.
The forward rotation and the reverse rotation operation in each liquid feed pump P1 are performed in the lever swinging direction slit portion 212b formed of the bulging portion among the slits 212 of the circular slit plate 205 (see FIG. 7) used for the drive switching mechanism. This is performed in the process in which the circular slit plate 205 moves while the switching gear shaft 203a is positioned.
In FIG. 10, for the sake of convenience, a time lag is provided between the selection times of each pump P1, but the actual selection time is one rotation of the rotary drive motor 206 in accordance with the rotation angle shown in FIG. It is performed continuously in.
Further, the rotation angle shown in FIG. 9 is detected by a sensor (not shown) disposed in the vicinity of the cam to prevent an erroneous operation such that the selection timing of the liquid feed pump P1 changes.

On the other hand, in FIG. 8, the sliding gear 505 is integrated at a substantially central portion in the axial direction of the sliding rod 506 disposed between the opposing surfaces of the rotation direction switching cam 504 c.
The sliding rod 506 is pressed and moved in the axial direction when the rotation direction switching cam 504c comes into contact therewith.

Transmission gears 509 and 510 that mesh with the forward and reverse gears 507 and 508 are disposed on opposite sides of the sliding rod 506 in the axial direction across the position of the sliding gear 505.
The transmission gears 509 and 510 have an arrangement relationship in which the sliding rod 506 is inserted into the center of rotation and the sliding rod 506 can freely rotate. For this reason, the transmission gears 509 and 510 are not supported by the sliding rod 506 but are rotatably supported by a non-illustrated immovable portion.

  The forward and reverse gears 507 and 508 are gears that determine the rotation direction of the liquid feed pump P <b> 1 by drive transmission from the transmission gears 509 and 510. Therefore, when one of the transmission gears 509 and 510 is driven, either the forward rotation gear 507 or 508 for reverse rotation on the side meshing with either of the driven transmission gears 509 and 510 is driven.

  Further, the forward and reverse gears 507 and 508 are gears arranged on the input side of the gear train reaching the drive gear 201 of the liquid feed pump P1, and the output side of the gear train is denoted by the reference numeral in FIG. A common gear indicated by 512 is arranged.

On the other hand, the sliding gear 505 is a gear capable of moving the sliding rod 506 in the axial direction together with the sliding rod 506.
For this reason, the sliding gear 505 can switch the rotation direction in the liquid feeding pump P1 by driving one of the transmission gears 509 and 510 with respect to the forward and reverse gears 507 and 508.

Further, the sliding gear 505 is engaged with one of the transmission gears 509 and 510 to transmit a driving force of the rotation driving motor 206 to the forward or reverse gears 507 and 508 (hereinafter referred to as a rotation driving force transmission mechanism). For the sake of convenience, a driving force transmission mechanism may also be expressed).
The driving force transmission mechanism is a mechanism that transmits a driving force when the rotary drive motor 206 rotates in the second direction to the forward or reverse gears 507 and 508.

Driving force is transmitted from the sliding gear 505 to the transmission gears 509 and 510 via a dog clutch constituted by a convex portion 505a and concave portions 509a and 510a provided on the sliding gear 505 and the transmission gears 509 and 510, respectively. Done.
That is, when the convex portion 505a is fitted into one of the concave portions 509a and 510a according to the direction in which the sliding rod 506 moves, the transmission gear 509 having either of the concave portions 509a and 510a on the side where the convex portion 505a is fitted. , 510 are driven.
In FIG. 8, reference numeral 511 denotes an elastic body for facilitating engagement of the concave portions 509a and 510a with the convex portion 505a described above when the dog clutch is engaged and for relaxing and absorbing the shock at the time of engagement. is there.

  In the drive mechanism having the above-described configuration, the rotation in the first direction and the second direction by the single rotary drive motor 206 is performed in the first and second directions indicated by reference numerals 500 and 501 in FIG. Transmission control is performed by the clutch.

  In FIG. 8, the first clutch 500 is arranged on the first driving force transmission path from the rotational drive motor 206 to the drive switching mechanism, as shown in FIG. Specifically, the slit drive gear 207 that rotationally drives the circular slit plate 205 of the drive switching mechanism and the idler gear 502 that meshes with the rotation direction switching transmission gear 503 used for the rotation direction switching mechanism are arranged between the rotation drive motor 206 and the idler gear 502. Has been.

  On the other hand, as shown in FIG. 8, the second clutch 501 is disposed in a second driving force transmission path from the rotation driving motor 206 to the sliding gear 505 used in the rotation direction switching mechanism.

  Although the first and second clutches 500 and 501 do not show a detailed configuration, a configuration in which an outer peripheral surface includes a gear portion and a clutch portion capable of controlling driving force transmission with the gear portion is used. ing.

  In the first clutch 500 arranged in the first driving force transmission path, the rotary driving motor 206 used as the single driving source 105 rotates in the first direction (the direction indicated by the arrow F in FIG. 8). The second clutch 501 used as a clutch for transmitting the driving force in this case and disposed in the second driving force transmission path is such that the rotary drive motor 206 is in the second direction (the direction indicated by the arrow R in FIG. 8). Used as a clutch to transmit driving force when rotating.

In the present embodiment, when the rotary drive motor 206 used as a single drive source rotates in the first direction, the first clutch 500 disposed in the first drive force transmission path is configured as described above. Thus, the driving force is transmitted to the drive switching mechanism and the rotation direction switching mechanism.
When the rotational drive motor 206 rotates in the second direction, the driving force is transmitted to the driving force transmission mechanism by the second clutch 501 disposed in the second driving force transmission path.

  The timing when the rotation drive motor 206 rotates in the first direction and the timing when the rotation drive motor 206 rotates in the second direction, and the pump selection state and the normal rotation and reverse rotation timing at this time are as shown in FIGS.

FIG. 11 schematically shows a transmission path from the single rotary drive motor 206 to the drive gear 201 of the liquid feed pump P1 via the clutches 500 and 501 based on the configuration shown in FIGS. FIG.
In FIG. 11, an arrow indicated by a one-dot chain line indicates a transmission path for driving switching, an arrow indicated by a two-dot chain line indicates a transmission path for switching the rotation direction, and an arrow indicated by a solid line indicates a transmission path for driving force transmission. Each means a transmission path.
In addition, the reference numerals of the transmission members are given the numbers of the drawings to be referred to in parentheses.

First, a transmission path for drive switching will be described.
At the time of drive switching, as indicated by the one-dot chain line arrow, when the rotation drive motor 206 rotates in the first direction, the rotation is transmitted to the idler gear 502 via the first clutch 500.
The rotation is transmitted from the idler gear 502 to the circular slit plate 205 through the slit driving gear 207. In FIG. 11, in addition to the slit driving gear 207 that meshes with the idler gear 502, the slit driving gear 207 is also shown on the circular slit plate 205 side. However, as shown by reference numerals P1 and P1 ′, a plurality of slit driving gears 207 are shown. This means that the slit driving gears 207 are provided for each of the liquid feed pumps, and the slit driving gears 207 are driven simultaneously.
When the circular slit plate 205 rotates, as described in FIG. 7B, the switching gear 203 that meshes with the drive gear 201 as the rotational phase of the lever swinging direction slit portion 212b formed of the bulging portion changes. The position of changes.
Thereby, the liquid feed pump P1 to be driven is selected.
In FIG. 11, an alternate long and short dash line arrow indicating a transmission path is branched from the slit driving gear indicated by reference numeral 207, and this is indicated by a plurality of pumps according to the rotation of the circular slit plate 205 from the slit driving gear 207. When one of P1 is selected, it means a state in which another liquid feed pump P1 is not selected.

Next, a transmission path for rotation direction switching executed when the rotation drive motor 206 rotates in the same direction as when pump selection is performed will be described.
When the rotational direction is switched, as indicated by a two-dot chain line arrow (corresponding to an arrow indicated by Fa in FIG. 8), when the rotation drive motor 206 rotates in the first direction, the rotation causes the first clutch 500 to rotate. To the idler gear 502.
The rotation is transmitted from the idler gear 502 to the rotation direction switching cam gears 504a and 504b via the rotation direction switching transmission gear 503.
When the rotation direction switching cam 504c rotates with the rotation of the rotation direction switching cam gears 504a and 504b, as described with reference to FIG. 8, any of the transmission gears 509 and 510 from the sliding gear 505 as the sliding rod 506 moves. Crab rotation is transmitted.
When the rotation is transmitted to one of the reach gears 509 and 510, the rotation is transmitted to one of the forward and reverse gears 507 and 508 engaged with either of the gears 509 and 510.
Thereby, the rotation direction in the selected liquid feeding pump P1 is determined.

Next, a path for transmitting a driving force to the selected liquid feed pump P1 when the rotation direction of the selected liquid feed pump P1 is determined will be described.
The transmission of the driving force is performed when the rotation drive motor 206 rotates in the second direction different from the above-described drive switching and rotation direction switching.
In FIG. 11, the driving force from a single rotational drive motor 206 is transmitted to the second clutch 501 as indicated by the solid line, and the meshing position is determined by the sliding gear 505. 507 or 508.
The driving force from each of the forward and reverse gears 507 and 508 is transmitted to an idler gear 208 whose transmission and disengagement state is determined by the switching gear 203 via a gear train including the common gear 512 shown in FIG. The In FIG. 11, for the sake of convenience, reference numeral S indicates that the idler gear 208 is coaxially supported so as to correspond to each liquid feed pump P <b> 1.
Since the idler gear 208 is coaxially supported as indicated by S, the idler gear 208 rotates simultaneously with the transmission of the driving force from either the forward rotation gear 507 or the reverse rotation gear 507 and the selected transmission gear. It seems that the driving force is also transmitted to the driving gear 201 of a liquid feeding pump other than the liquid pump P1 (indicated by reference numeral P1 ′ in FIG. 11 for convenience).
However, in this embodiment, since the meshing state of the switching gear 203 and the idler gear 208 for the liquid feed pump P1 selected at the time of switching the drive executed before transmitting the driving force is determined, the selection is made. The drive force is not transmitted to the drive gear 201 of the liquid feed pump P1 ′ that is not used.
This will be described with reference to FIG. 11. As described with reference to FIG. 7B when switching the drive, the switching gear for the drive gear 201 of the liquid feed pump P 1 selected by the rotation of the circular slit plate 205. Only the engagement state 203 is determined. For this reason, the meshing of the switching gear 203 with the drive gear 201 of the liquid pump P1 ′ that is not selected means that the gears are released apart from each other as shown in FIG.
Therefore, even when the idler gear 208 rotates simultaneously, the driving force is not transmitted to the unselected liquid feed pump P1 ′ (in FIG. 11, for the sake of convenience, the transmission path to the liquid feed pump P1 ′ is connected. (There are no broken arrows.)
As a result, it is possible to transmit the driving force only after the rotation direction of the rotation drive motor 206 is switched from the first direction to the second direction, so that the rotation direction of the single rotation drive motor 206 is restricted. And the selected pump can be driven.

When the driving force is transmitted through the transmission path shown in FIG. 11, in order to enable forward / reverse on the liquid feed pump P1 side according to switching of each forward / reverse gear, the gear train in each direction is changed. It is stipulated in the following conditions.
In the forward rotation gear 507 and the reverse rotation gear 508, when the number of gears in the gear train including the forward rotation gear 507 is A and the number of gears in the gear train including the reverse rotation gear 508 is B, the reverse rotation gear train B is In the case of A <B, B = A + 1 + 2n (n is 0 or an integer), and in the case of A> B, the relationship A = B + 1 + 2n (n is 0 or an integer) is established. Thus, when the rotation drive motor 206 rotates in the second direction, the rotation of the rotation drive motor 206 is transmitted depending on which of the forward rotation gear train and the reverse rotation gear train is transmitted. The rotation direction of the pump drive gear 201 that drives the liquid feed pump P1 changes.

  In the above embodiment, only by using the single drive source 105, the drive timing selection and the selected pump P1 for all the liquid feed pumps P1 provided in the ink supply flow paths of the respective colors are used. The liquid can be fed and returned. As a result, it is not necessary to provide a drive source for the liquid feed pump in each supply flow path, so that the installation space for these drive sources can be reduced in size and simplified.

  In this embodiment, in addition to the liquid feed pump P1 as described above, the suction flow path provided in the maintenance / recovery mechanism of the discharge head can also be targeted. In this case, as described in the specification of Japanese Patent Application No. 2012-120746 which is the prior application of the present applicant, each of the suction pumps is similar to the case of the liquid feed pump P1 and the drive switching mechanism described above. The structure driven by the single drive source which drives an apparatus is employ | adopted.

Next, a modified example related to the configuration of the above-described embodiment will be described.
FIG. 12 is a diagram showing a modification of the above-described pump drive device.
In the configuration shown in the figure, a linear slit plate 209 capable of linear motion is provided instead of the circular slit plate shown in FIG.
In FIG. 12, a slit drive cam 211 and a slit drive link 210 that convert the rotary motion of the slit drive gear 207 described above into linear motion are used as members for imparting linear motion to the linear slit plate 209.

  In the pump drive device (indicated by reference numeral 200 'for convenience), when the switching gear shaft 203a is in the linear slit portion 212c in the slit 212, the position of the switching gear 203 is controlled by the restriction of the slit 212 and the restriction of the switching gear swing lever 203b. Is a drive non-transmission position separated from the pump drive gear 201.

In the pump driving device 200 ′, the rotational driving force when the rotational driving motor 206 rotates in the first direction is transmitted to the switching gear 203 through the central driving gear 204 and the idler gear 208.
The switching gear 203 can move while rotating around the idler gear 208 to the pump drive gear 201 that inputs drive to the pump P1 by the linear slit plate 209 and to a position that is connected or separated.

Similar to the configuration shown in FIG. 7, the slit drive cam 211 generates the driving force of the rotation drive motor 206 when the rotation direction is set in the first direction in the rotation drive motor 206 used as a single drive source. It is transmitted and rotates.
When the slit drive cam 211 rotates, the slit drive link 210 swings, so that the linear slit plate 209 moves in the left-right direction in FIG.

  At this time, when the lever swing direction slit portion 212b of the slit 212 slides to the position of the switching gear 203, the switching gear 203 is moved to the lever swing direction slit portion 212b by the biasing force of the switching gear biasing spring (not shown). Along the periphery of the idler gear 208. As a result, the switching gear 203 moves to a position where it is connected to the pump drive gear 201. In this state, by driving the rotational drive motor 206, the rotational driving force is transmitted to the pump P1 via the pump driving gear 201.

In the pump driving device 200 ′ shown in FIG. 12, the switching gear 203 and the pump driving gear 201 are connected to each other by sliding the position of the lever swing direction slit portion 212b in the linear slit plate 209. The state will be selected.
In addition, the driven portion to which driving is input via the switching gear 203 is not limited to a pump, and power may be transmitted to another maintenance unit such as a maintenance unit or an air release valve.
The configuration of the lever swing direction slit portion 212b in the linear slit plate 209 is based on the same principle as the lever swing direction slit portion 212b formed of the bulging portion of the slit 212 described in FIG. 7C. It has been adopted.

A further modification of the pump drive device shown in FIG. 12 is shown in FIG.
In the configuration shown in FIG. 13, a switching gear 203 supported at one end of a swing lever 250 that can swing in conjunction with an eccentric cam 251 is used as a member for switching drive transmission to the pump P1.
The swing lever 250 that contacts the eccentric cam 251 is maintained in contact with the eccentric cam 251 by a spring 252 that is hooked at the end opposite to the side on which the switching gear 203 is supported.

  The rotational driving force applied to the eccentric cam 251 is transmitted when the rotational direction in the first direction is set in the rotational driving motor 206 used as a single driving source, as in the configuration shown in FIGS. Is done.

According to the cam profile (phase) when the eccentric cam 251 rotates, the swing lever 250 is in a position to transmit the rotational driving force to any one of the switching gears 203, and the rotation is transmitted. In response to the rotation of the pump drive gear 201, the liquid feed pump P1 is driven.
The eccentric cam 251 employs a cam profile having the same principle as the lever swinging direction slit portion 212b formed of the bulging portion of the slit 212 described in FIG. 7C.
The transmission paths having the configurations shown in FIGS. 12 and 13 cited as the modified examples can obtain the same paths as shown in FIG.

  FIG. 14 is a diagram showing a configuration of the pump P1 driven by the above-described pump driving device, and a tube pump (hereinafter, the tube pump is denoted by reference numeral P1 for convenience) is used as the liquid feed pump P1 shown in FIG. It is done.

  The tube pump P1 shown in FIG. 14 has a configuration capable of feeding liquid while always crushing a part of the tube and closing the flow path. That is, the ink in the tube is pushed out by utilizing the fact that the position of the tube that is crushed by the eccentric cam that rotates eccentrically inside the pump moves in accordance with the rotation of the eccentric cam. In addition, the tube support wall on the inner surface of the tube and the outer peripheral surface of the eccentric cam can be crushed on both sides of the maximum outer diameter portion of the eccentric cam even when the maximum outer diameter portion of the eccentric cam faces upward. The inner surface of the pump is formed in such a shape that the distance between the two becomes narrower.

  As a type of pump, a type in which liquid is fed only by rotational driving in one direction such as a suction pump, while liquid feeding is performed during normal rotation, while liquid feeding is not possible during reverse rotation. For this reason, when a configuration capable of forward / reverse rotation is used for the drive source, an increase in the drive source is suppressed by using the drive force at the time of reverse rotation as the drive force for devices other than the pump.

  Therefore, when the drive source capable of forward and reverse rotation as described in the present embodiment is used for the case where the tube pump shown in FIG. Cannot be used as a driving force for other devices. However, by using the switching mechanism, the rotation direction switching mechanism, and the driving force transmission mechanism described in the present embodiment, it is possible to use a drive source capable of forward and reverse rotation as a drive source for other devices.

DESCRIPTION OF SYMBOLS 1 Apparatus main body 10 Ink cartridge 34 Liquid discharge head 35 Head tank 103 Supply flow path 201 Pump drive gear 203 Switching gear 206 Rotation drive motor 212 Slit plate 500, 501 One-way clutch 251 Eccentric cam 504a, 504b Rotation direction switching cam gear 504c Rotation Direction switching cam P1 Liquid feed pump

Japanese Patent No. 4019694

Claims (8)

A plurality of ejection heads that eject different types of droplets;
A plurality of head tanks for supplying different types of liquid to the plurality of ejection heads;
A plurality of liquid main tanks for supplying different types of liquid to the plurality of head tanks;
A plurality of liquid feed pumps for sending liquid from each of the plurality of liquid main tanks to the plurality of head tanks, and reversely feeding the liquid from the plurality of head tanks to the plurality of liquid main tanks;
A single drive source for driving the plurality of liquid feeding pumps, capable of rotating in both directions of a first direction and a second direction opposite to the first direction;
A drive switching mechanism that selects which of the plurality of liquid feeding pumps is driven by rotating the single drive source in the first direction;
A rotation direction switching mechanism for switching the rotation direction of the liquid feed pump with respect to the liquid feed pump selected by the drive switching mechanism by rotating the single drive source in the first direction;
By rotating the single drive source in the second direction, the rotational driving force is transmitted in the rotational direction switched by the rotational direction switching mechanism to the liquid feed pump selected by the drive switching mechanism. A rotational driving force transmission mechanism;
Arranged in a first driving force transmission path from the single driving source to the driving switching mechanism, and only the rotational driving force in the first direction is switched from the single driving source to the driving switching mechanism and the rotational direction. A first clutch that transmits to the mechanism;
It is arranged in a second driving force transmission path from the single driving source to the rotational driving force transmission mechanism, and only the rotational driving force in the second direction is transferred from the single driving source to the rotational driving force transmission mechanism. A second clutch to transmit,
A liquid ejection apparatus comprising: The drive switching mechanism selects the liquid feed pump to be driven among the plurality of liquid feed pumps by rotationally driving the single drive source in the first direction,
The rotation direction switching mechanism switches the rotation direction of the liquid feeding pump selected by the drive switching mechanism by rotationally driving the single drive source in the first direction,
The rotational driving force transmission mechanism rotates the single drive source in the second direction, and rotates the liquid feed pump selected by the drive switching mechanism by the rotational direction switching mechanism. The liquid ejection device according to claim 1 , wherein a rotational driving force is transmitted to the liquid ejection device. The drive switching mechanism is provided with a switching gear that can be brought into and out of contact with a liquid feeding pump drive gear that transmits a driving force from the driving source to the liquid feeding pump. 3. The liquid ejection apparatus according to claim 1, wherein the driving force from the driving source is selectively transmitted to the driving gear for the liquid feeding pump according to the operation. The switching gear is supported so as to be able to contact and separate with respect to the drive gear for the liquid feed pump with a rotation shaft of an idler gear corresponding to a planetary gear meshing with the central gear as a fulcrum, and is provided coaxially with the central gear so as to be circumferential. Drive for the liquid feeding pump by entering the bulging part according to the rotation of the slit plate made of a different diameter member having a bulging part directed toward the drive gear side for the liquid feeding pump in a part of the direction The liquid ejection apparatus according to claim 3 , wherein the liquid ejection apparatus is accessible to a position where the gear meshes with the gear. Claim the switching gear, which is supported at one end of the swing lever capable conjunction with the eccentric cam, characterized in that it is a separably to the pump drive gear in accordance with the swing position of the swing lever 3. The liquid ejection device according to 3 . Wherein the rotation direction switching mechanism, forward rotation and reverse rotation gear of said liquid delivery pump is provided independently,
The forward and reverse gears are provided with sliding gears supported by sliding rods extending to the positions of the forward and reverse gears so as to be opposed to each other, and the first and second clutches are used as the first and second clutches. The sliding rod is pressed by an eccentric member that operates during rotation in the first direction by the drive source via the one-way clutch used, and thus faces either the forward rotation gear or the reverse rotation gear. The sliding gear is positioned as described above, and from the positioned sliding gear to the forward rotation gear or the reverse rotation gear when rotating in the second direction by the drive source via the one-way clutch. liquid ejecting apparatus according to one of claims 1 to 5 the rotational force, characterized in that it is transmitted. The forward and reverse gear trains are those for reverse rotation when the number of gears of the forward and reverse gear trains is A and the number of gears of the reverse gear train is B. The number of gears B in the gear train is B = A + 1 + 2n (n is 0 or integer) when A <B, and A = B + 1 + 2n (n is 0 or integer) when A> B. The liquid ejection apparatus according to claim 6 , wherein the liquid ejection apparatus is a liquid ejection device.   An image forming apparatus using the liquid ejection device according to claim 1.

Images