JP7188097B2 - portable printer - Google Patents

Description

The present invention relates to a portable printing device, and more particularly to technology for preventing ink leakage during use.

As disclosed in Patent Document 1, for example, a portable printing apparatus includes a grip portion, a power source, a cartridge that stores ink, an ink head that ejects ink in the cartridge by the power supplied from the power source, and image data. and a control unit for controlling ejection of ink from the ink head according to the condition.

In this printing apparatus, when printing on the surface of the object to be printed, the controller causes the ink head to eject ink while the ink head faces the surface of the object to be printed.

JP 2004-106339 A

In such a portable printing apparatus, there is a case where the attitude of the printing apparatus is changed according to the position of the surface of the printing object. If the ink head and the cartridge are in a fixed positional relationship, the position of the ink surface in the cartridge may fluctuate, causing the ink head to suck in air and cause ink ejection failure.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a cartridge-equipped portable printing apparatus in which, when the orientation of the printing apparatus is changed during use, the position of the ink liquid surface in the cartridge is less likely to fluctuate, and good ejection characteristics can be maintained. do.

In order to solve the above problems, a portable printing apparatus according to one aspect of the present invention includes a spherical cartridge having at least one internal space in which ink is stored, and the cartridge having an inclination within a predetermined range with respect to the vertical direction. In a reference posture, which is a posture, a weight provided at the bottom of the cartridge, a case that houses the cartridge, and a case that is arranged between the case and the cartridge, in all directions along the outer surface of the cartridge, a bearing unit that supports the cartridge in the reference posture so as to be relatively movable with respect to the case; an ink head that has a nozzle surface on which a plurality of nozzles are formed and is supported by the case; a tube that is connected to the head, extends into the internal space through the upper portion of the cartridge in the reference posture, and has the other end located near the lower portion of the cartridge to communicate the cartridge and the ink head; and a control unit that controls an ejection operation of ejecting ink from the ink head.

According to the above configuration, for example, even when the posture of the printing apparatus is changed, the bearing unit arranged between the case and the cartridge allows the printing apparatus to move in all directions along the outer surface of the cartridge with respect to the case. The attitude of the cartridge is adjusted so that the cartridge can freely move relative to the cartridge and the weight provided at the bottom of the cartridge is always directed downward in the vertical direction. As a result, even when the posture of the printing apparatus is changed during use, the position of the ink surface in the cartridge is less likely to fluctuate, and ink is stably supplied to the ink head via the tube.

Therefore, it is possible to prevent the ink head from sucking air and causing an ejection failure due to a change in the posture of the printing apparatus. Therefore, it is possible to print satisfactorily on the surface of the object to be printed.

According to the present invention, in a portable printing apparatus provided with a cartridge for storing ink, when the posture of the printing apparatus is changed during use, the position of the ink liquid surface in the cartridge is prevented from fluctuating. It can print well on the surface of the object.

1 is an external view of a printer according to a first embodiment; FIG. FIG. 2 is a cross-sectional view of the printer of FIG. 1 with an ink head disposed on the upper side; FIG. 2 is a cross-sectional view of the printer of FIG. 1 with an ink head disposed on the lower side; 2 is an external view of a winding unit of the printer of FIG. 1; FIG. 2 is a cross-sectional view showing a state in which the position of the ink head of the printer of FIG. 1 is changed; FIG. 2 is a diagram showing the internal structure of a valve unit of the printer of FIG. 1; FIG. FIG. 10 is a schematic diagram of a cartridge of a printer according to a second embodiment, viewed from above;

Each embodiment will be described below with reference to the drawings.

(First embodiment)
FIG. 1 is an external view of a printer 1 according to the first embodiment. Printer 1 includes case 4 and ink head 7 . As for the bearing unit 5, only the bearing balls 14 are shown. FIG. 2 is a cross-sectional view of the ink head 7 positioned above the case 4 . 3 is a cross-sectional view of the ink head 7 positioned below the case 4. FIG. 2 and 3 schematically show the internal structure of the ink head 7. FIG.

1 to 3, in addition to the case 4 and the ink head 7, the printer 1 includes a cartridge 2, a weight 3, a bearing unit 5, a winding unit 6, a tube 8, a control unit 9, an encoder 10, a plurality of A wheel 12, a valve unit 13, a battery 18, and the like are provided. The printer 1 of this embodiment has a configuration in which the ink head 7 is supported by the case 4 via a winding unit 6 (described later).

The printer 1 is portable and can print on the print target 40 in any posture. The printer 1 is driven by power from the battery 18 . The printer 1 is used while being held by an operator, but may be used while being installed on a device such as a robot arm.

The cartridge 2 is formed in a spherical shape and has at least one internal space S. Ink 30 is stored in the internal space S. An opening 2a is provided in the upper portion of the cartridge 2 in a reference posture, which will be described later. A vent 2c is provided in the vicinity of the opening 2a. The ink 30 flows into the internal space S through the opening 2a, and the outside air flows into the internal space S through the ventilation port 2c.

The outer surface of the cartridge 2 is provided with a guide groove 2b. The guide groove 2b extends along the vertical direction from the opening 2a, and covers the entire circumference of the cartridge 2, for example. The guide groove 2b may be formed only on the half circumference of the cartridge 2. FIG. The groove width of the guide groove 2b is equal to or greater than the outer diameter of the tube 8. As shown in FIG. The unrolled tube 8 is guided and further fitted.

The weight 3 is arranged below the cartridge 2 in the reference posture. The weight 3 of this embodiment is positioned below the internal space S. As shown in FIG. The weight 3 has a circular peripheral shape when viewed from the vertical direction, and the center of the weight 3 overlaps the center of the cartridge 2 .

Case 4 accommodates cartridge 2 . The case 4 has a spherical inner wall surface 4a and an opening 4b. The inner wall surface 4 a supports the cartridge 2 by contacting the plurality of bearing balls 14 . The opening 4b is positioned above the case 4 in the reference position, and the tube 8 is inserted through the opening 4b. The external shape of the case 4 is, for example, spherical. Of course, the external shape may be other than spherical, such as a cubic shape. As an example, the case 4 has an outer diameter dimension that facilitates handling by the operator.

The bearing unit 5 is arranged between the case 4 and the cartridge 2 . The bearing unit 5 has a plurality of bearing balls 14 and a support member 15 . The bearing unit 5 is combined with the outer surface of the cartridge 2 and the inner wall surface 4 a of the case 4 . The bearing unit 5 supports the cartridge 2 in all directions along the outer surface of the cartridge 2 so as to be relatively movable with respect to the case 4 while maintaining the reference posture. As a result, the case 4 can move in all directions along the outer peripheral surface of the cartridge 2 in the reference posture.

A plurality of bearing balls 14 are discretely arranged along the outer surface of the cartridge 2 . At this time, the bearing balls 14 contact the inner wall surface 4 a of the case 4 and the outer surface (outer wall surface) of the cartridge 2 . The support member 15 rotatably supports all the bearing balls 14 . As a result, each bearing ball 14 is fixed in relative position by the support member 15 . Also, none of the bearing balls 14 are fitted into the guide grooves 2b.

The support member 15 is formed in a frame shape, for example. Of course, the supporting member 15 is not limited to a frame-like one, and it is sufficient that the bearing balls 14 are substantially equally distributed along the spherical surface. Moreover, the bearing unit 5 may be of a type other than the ball bearing described above. For example, the cartridge 2 may have a plurality of support members on its outer surface, with the bearing balls 14 supported thereon.

The printer 1 has a case 4, a bearing unit 5 and a cartridge 2, and the cartridge 2 is spherical. A bearing unit 5 is sandwiched between the case 4 and the cartridge 2, and the case 4 and the cartridge 2 are relatively movable. Also, as shown in FIGS. 2 and 3, a weight 3 is provided at the bottom of the cartridge 2 . Therefore, the cartridge 2 always has the weight 3 at the bottom. In other words, the inclination of the cartridge 2 with respect to the vertical direction is always kept within a predetermined range during the relative movement. At this time, the liquid surface of the ink 30 in the cartridge 2 stops at a substantially constant position. Here, the attitude of the cartridge 2 in which the inclination with respect to the vertical direction is within a predetermined range is referred to as a reference attitude.

The ink head 7 has a substantially cubic shape and has a nozzle surface 7a and a supporting surface facing in the thickness direction. The nozzle surface 7a is a flat surface, and a plurality of nozzles 7b are opened. The plurality of nozzles 7b are arranged in one direction to form a nozzle row. On the other hand, several functions are arranged on the support surface.

Inside the ink head 7, a sub-tank 7c and a plurality of individual ink flow paths 7d are formed. Each individual ink channel 7d is connected to a sub-tank 7c and includes a pressure chamber and a piezoelectric element in addition to the nozzle 7b.

Inside the ink head 7, a sub-tank 7c and a plurality of individual ink flow paths 7d are formed. The sub-tank 7c is connected to the tube 8. Each individual ink channel 7d is connected to a sub-tank 7c and includes a pressure chamber and a piezoelectric element in addition to the terminal nozzle 7b.

Ink is supplied from the tube 8 and temporarily stored in the sub-tank 7c. The ink in the sub-tank 7c is distributed from its outlet to each individual ink flow path 7d and reaches the nozzle 7b via the pressure chamber. Here, when the volume of the pressure chamber is changed by the piezoelectric element, an ink droplet is ejected from the nozzle 7b.

A battery 18 , a control unit 9 and an encoder 10 are arranged on the support surface of the ink head 7 . The battery 18 is rechargeable as an example, and is a drive source for the control unit 9, the encoder 10, and the piezoelectric element. The control unit 9 controls the ink ejection operation of the ink head 7 .

Note that the battery 18 may be of a type that is connected to a commercial power source. Also, the arrangement of the control unit 9, the encoder 10, and the battery 18 is not limited to this, and at least one of them may be separated from the ink head 7.

The winding unit 6 winds up the excess of the tube 8 or feeds out the shortage of the tube 8 according to the change in the distance between the ink head 7 and the upper portion of the cartridge 2 along the outer surface of the cartridge 2 . conduct. The winding unit 6 is interposed between the ink head 7 and the case 4 to connect them.

4 is an external view of the winding unit 6. FIG. The winding unit 6 has a cylindrical winding body 16 for spirally winding the tube 8 and a biasing member 17 for biasing the winding body 16 . FIG. 4 shows a state in which the winding body 16 and the biasing member 17 are separated.

The winding body 16 is pivotally supported by the ink head 7 and biased to one side in the circumferential direction by a biasing member 17 . As an example, the biasing member 17 is preferably a spiral spring. A winding groove 16 a is formed in the peripheral surface of the winding body 16 so as to spirally revolve around the axis of the winding body 16 . The winding body 16 is rotatable around its axis. The tube 8 is wound on the winding unit 6 so as to fit in the winding groove 16a. As a result, the tube 8 is housed in the winding groove 16a. At this time, one end 8a of the tube 8 is communicated with the sub-tank 7c, and the other end 8b is at a predetermined position within the cartridge 2, so that the middle portion of the tube 8 is wound on the winding body 16. As shown in FIG.

The tube 8 has one end connected to the ink head 7 , extends into the internal space S through the upper portion of the cartridge 2 in the standard posture, and the other end located near the lower portion of the cartridge 2 . In this embodiment, a portion of the other end 8b of the tube 8 is in contact with the lower portion of the cartridge 2. As shown in FIG.

Tube 8 is at least longer than the diameter of cartridge 2 . When the ink head 7 is in any position, the tube 8 can be divided into three partial tubes. A first partial tube in the internal space S, a second partial tube wound on the winding unit 6, and a third partial tube fitted in the guide groove 2b of the cartridge 2. FIG. Of these, the third partial tube has a length corresponding to the change in the distance between the ink head 7 and the upper portion of the cartridge 2 and is arranged between the case 4 and the cartridge 2 .

Here, in the printer 1, the inclination of the cartridge 2 with respect to the vertical direction is always kept within a predetermined range regardless of the attitude of the ink head 7 (FIGS. 2 and 3). Within the internal space S, the positional relationship between the other end 8b of the tube 8 and the ink 30 is maintained. This prevents air from being sucked into the internal space S when the ink 30 is supplied to the ink head 7 .

In this embodiment, the valve unit 13 is interposed between the ink head 7 and the winding unit 6 . One end 8a of the tube 8 communicates through the valve unit 13 with the sub-tank 7c.

FIG. 6 is a schematic diagram showing the internal structure of the valve unit 13. As shown in FIG. The valve unit 13 is provided in the middle of the ink flow path R4, and switches the communication destination with which the cartridge 2 communicates. The ink flow path R4 communicates the winding unit 6 and the ink head 7 with each other. Further, the printer 1 includes a communication channel R5 that communicates the outside with the valve unit 13 .

As shown in FIG. 6, the valve unit 13 has a base portion 11 in which a three-way flow path 11a is formed, and three valves V1 to V3 arranged in the three-way flow path 11a. The three-way channel 11a has a first channel portion 11b, a second channel portion 11c, and a third channel portion 11d. Of these, the first channel portion 11b and the second channel portion 11c are interposed in the middle of the ink channel R4. The third channel portion 11d is connected to the communication channel R5.

The first channel portion 11b is connected to the ink channel R4 on the side of the ink head 7, and the valve V2 is arranged in the middle. The second flow path portion 11c is connected to the ink flow path R4 on the cartridge 2 side, and the valve V3 is arranged in the middle. The third flow path portion 11d communicates with an external ink tank via a communication flow path R5, and a valve V1 is arranged in the middle. The opening and closing operations of the valves V1 to V3 are controlled by the control unit 9 as an example, but may be performed manually. The valve unit 13 can switch the communication state of the flow path between the first to third modes depending on the combination of the open and closed states.

The first form is a form in which the printing ink path R1 is formed by communicating between the cartridge 2 and the ink head 7, and the printing ink path R1 is blocked from the outside. In the first mode, valve V1 is closed and valves V2 and V3 are open. As a result, when the ink 30 is consumed in the printing operation, the ink 30 is replenished to the ink head 7 via the printing ink path R1.

The second mode is a mode in which the ink path for purging R2 is formed by communicating between the ink head 7 and the outside, and the ink path for purging R2 is blocked with respect to the cartridge 2. FIG. In the second mode, valve V3 is closed and valves V1 and V2 are opened. As a result, when purging is performed as a maintenance operation, the ink 30 can be pressure-fed from an external ink tank to the ink head 7 .

The third mode is a mode in which a replenishment ink path R3 is formed by communicating between the cartridge 2 and the outside, and the replenishment ink path R3 is blocked with respect to the ink head 7. FIG. In the third mode, valve V2 is closed and valves V1 and V3 are opened. As a result, when the remaining amount of ink in the cartridge 2 is low, the ink 30 can be refilled into the cartridge 2 from an external ink tank.

The control unit 9 includes an input section in addition to the unit body. The unit main body has, as an example, a calculation section and a storage section. The calculation section operates based on a predetermined program and controls the operation of each section of the printer. The storage unit stores this predetermined program, and also temporarily stores image data, instruction data, etc. input from the outside. For example, when forming an image on the print object 40, the calculation unit refers to the image data in the storage unit and drives the piezoelectric element based on this data.

Here, to the control unit 9, data about the relative movement distance and the relative movement speed of the ink head 7 with respect to the printing object 40 are sent from an encoder, which will be described later. Based on these two data, the control unit 9 controls the ejection operation of the ink head 7 (here, drive of the piezoelectric element). As a result, ink droplets of a predetermined size are ejected at a predetermined timing.

The input section of the control unit 9 includes an interface and an operation section. The interface accepts image data and instruction data from the outside by wire or wirelessly. The operation unit corresponds to a keyboard, a touch panel, or the like, and an operator inputs an instruction such as a print job.

The encoder 10 measures the relative movement distance between the ink head 7 and the printing object 40 along the surface of the printing object 40 and transmits the measurement result to the control unit 9 . The encoder 10 of this embodiment includes an encoder body 10 a and an encoder wheel 19 . Of these, the encoder wheel 19 is also one of the wheels 12 . When the printer 1 moves along the surface of the printing object 40, the encoder body 10a detects the rotating state of the encoder wheel 19. As shown in FIG. At this time, the relative movement distance and the relative movement speed with respect to the ink head 7 are measured.

Specifically, a plurality of wheels 12 are rotatably supported by the ink head 7 . A plurality of wheels 12 protrude from the nozzle surface 7 a by a predetermined distance and come into contact with the surface of the printing object 40 . At this time, the number of rotations and the rotation speed of the encoder wheel 19 are converted into the relative movement distance and the relative movement speed by the encoder main body 10 a and transmitted to the control unit 9 . At least one of the control unit 9, the encoder 10, and the battery 18 may be arranged at a position separated from the ink head 7.

Here, the biasing force (winding force F _W ) of the biasing member 17 will be considered. In the present embodiment, the biasing force of the biasing member 17 acts as a rotational force on the winding body 16, and a force _FW in the winding direction (winding force _FW ) acts on the tube 8. FIG. As a result, the tube 8 is wound around the winding body 16 without slackening. When the attitude of the ink head 7 changes, a force acting against the winding force _FW acts on the tube 8 as the tube 8 is fed. However, this winding force _FW is set so that the cartridge 2 can maintain the reference posture regardless of the delivery of the tube 8 .

That is, as shown in FIG. 5, the take-up unit 6 displaces the cartridge 2 (ink head 7) from a state in which the insufficient amount of feed of the tube 8 is minimized to a state in which the insufficient amount of feed of the tube 8 is maximized. In a virtual plane formed by a virtual straight line L connecting the other end 8b of the tube 8 and the rotation center O of the cartridge 2 and a vertical line V passing through the rotation center O, a virtual straight line with respect to the vertical line V is formed. The take-up force _FW of the tube 8 is set so that the cartridge 2 can maintain a reference posture in which the change Δθ of the intersection angle θ of L is 0° or more and 10° or less. In FIG. 5, Δθ is shown slightly enlarged for explanation.

Here, when the biasing member 17 is composed of, for example, a spiral spring, and R _S is the radius of the biasing member 17 (same hereafter), the winding torque T _S of the biasing member 17 is given by the following equation 1 is represented by
[Formula 1]

T _S =R _S ×F _W

As Equation 1 indicates, the winding torque T _s depends on the radius R _s of the biasing member 17 . In order to allow the tube 8 to be wound while the cartridge 2 is in the reference position, it is desirable that the length of the biasing member 17 be such that fluctuations in the winding torque _Ts can be suppressed.

Further, the attitude of the cartridge 2 also changes slightly as the attitude of the ink head 7 changes. Therefore, _Rc is the radius of the cartridge 2, _{Ft is the force acting on the cartridge 2 in the circumferential direction, Rcw is} the shortest distance between the center of the cartridge 2 and the center of gravity of the weight 3, and W is the weight of the weight 3 ( ), the attitude torque _Tc acting from the cartridge 2 to the tube 8 is expressed by the following equation 2.
[Formula 2]

_Tc = _{Rc*Ft=Rcw * W} *sin([theta])

At this time, force transmission loss due to bending and friction of the tube 8 is taken into consideration. F this_lThen, the winding force F_W.is set based on Equations 3 and 4 below.
[Formula 3]

F._W.≦F_t+F_l

[Formula 4]

T._S.≤ (F_l+R_cw×W×sin(θ)/R_c)/R_S.

The biasing (spring) strength of the biasing member 17 is appropriately determined by setting the limit value of the intersection angle θ so that Equations 3 and 4 are established. Further, by setting the winding force _FW so as to satisfy Equation 3 and setting the winding torque _Ts so as to satisfy Equation 4, it is possible to maintain the cartridge 2 in a desired state. , the tube 8 can be fed out from the winding unit 6. As a guideline for the take-up force _FW , the variation Δθ of the crossing angle θ is set to 0° or more and 10° or less in consideration of suppressing the change in the positional relationship between the ink 30 and the other end 8b of the tube 8 as much as possible. It is desirable to set the cartridge 2 so that it can maintain the reference posture.

The operation of the printer 1 during use will be described below. When forming an image on the surface of the printing object 40, the operator directs the nozzle surface 7a of the ink head 7 toward the printing object 40 and brings the wheel 12 into contact with the surface. In this state, the operator instructs the control unit 9 to start the print job through the input section.

First, the control unit 9 puts the piezoelectric element in a standby state. At this time, the control unit 9 controls the battery 18 to apply a predetermined voltage to the piezoelectric element. After that, the control unit 9 waits for input of signals from the encoder 10 (measurement results of the relative movement distance and the relative movement speed described above).

After placing the piezoelectric element on standby, the control unit 9 may notify the operator that printing is ready. As the notification form, any one of buzzer sound notification, lamp emission, vibration of the printer 1 itself, and the like is adopted. After this, the operator will start moving (printing) the printer 1 relative to the surface.

When the printer 1 starts relative movement, the encoder wheel 19 also rotates together with the wheel 12 . At this time, the encoder 10 measures the relative movement speed and the relative movement distance by rotating the encoder wheel 19 and transmits the measurement results to the control unit 9 .

The control unit 9 controls driving of the piezoelectric element based on this measurement result. The control unit 9 obtains the position of the nozzle 7b and the displacement speed at this position from the measurement result, and determines the ejection timing and ejection amount of the ink droplets. As a result, printing is performed on the surface of the printing object 40 according to the image data.

During this printing operation, the attitude of the printer 1 in the vertical direction changes according to the position of the surface of the printing object 40 . However, due to the structural relationship between the case 4 and the cartridge 2 described above, the orientation of the cartridge 2 is held in the reference orientation.

Further, when the printer 1 is tilted with respect to the vertical direction, the case 4 moves relatively while leaving the cartridge 2 at its original position. Further, the guide groove 2b is arranged along the direction of inclination of the ink head 7 with respect to the cartridge 2 when viewed from the vertical direction. As a result, when the ink head 7 is tilted with respect to the cartridge 2, the tube 8 is let out by the necessary amount from the winding unit 6, and the force transmission loss associated with bending and friction is suppressed.

The orientation of the guide groove 2b in the direction of inclination associated with the inclination of the printer 1 is realized, for example, by fitting the tube 8 into the guide groove 2b in the upper portion of the cartridge 2. FIG. If the extending direction of the guide groove 2b and the inclination direction of the ink head 7 are different when viewed from the vertical direction, the tube 8 is laid in the guide groove 2b from the oblique side.

At this time, due to the rigidity of the tube 8 itself, a rotational force acts on the cartridge 2 obliquely to the side about its center. Since the cartridge 2 and the case 4 are configured to be relatively movable, the direction of inclination of the ink head 7 and the direction of extension of the guide groove 2b are aligned.

In the printer 1, the cartridge 2 has a vent 2c, and the internal space S communicates with the atmosphere. When the ink 30 is used for printing, outside air is taken into the internal space S through the air vent 2c according to the amount of decrease. Thereby, the pressure in the internal space S is maintained at the atmospheric pressure. Even if the posture of the printer 1 changes, the meniscus of the nozzle 7b will not be destroyed because the change in the back pressure is within a predetermined range.

As described above, according to the printer 1 , the bearing unit 5 is arranged between the case 4 and the cartridge 2 . Therefore, the case 4 and the cartridge 2 can freely move relative to each other in all directions along the outer surface of the cartridge 2 . A weight 3 is arranged below the cartridge 2 . The attitude of the cartridge 2 is adjusted so that the weight 3 is always at the bottom in the vertical direction. As a result, even if the posture of the printer 1 changes, the positional relationship between the liquid surface of the ink 30 in the cartridge 2 and the other end 8b of the tube 8 is maintained, and the ink 30 is stably transferred to the ink head 7 through the tube 8. supplied as In addition, the other end 8b (ink inlet) of the tube 8 is less likely to be exposed to air. Therefore, good ejection characteristics of the printer 1 can be maintained.

Also, in the printer 1 , a portion of the other end 8 b of the tube 8 is in contact with the lower portion of the cartridge 2 . Therefore, even if the posture of the printer 1 changes, it is possible to satisfactorily prevent the air in the internal space S from entering the other end 8b of the tube 8 .

The printer 1 also includes a winding unit 6 . As a result, the winding unit 6 can take in and out the necessary amount of the tube 8 according to the posture change of the printer 1 . Even if the tube 8 is long, the printer 1 can be made compact.

The tube 8 is arranged between the case 4 and the cartridge 2 in a length corresponding to the change in the distance between the ink head 7 and the upper portion of the cartridge 2 . Therefore, it is possible to prevent the tube 8 from interfering with the smooth relative movement between the cartridge 2 and the case 4 .

Further, a guide groove 2b extending vertically from the opening 2a is provided on the outer surface of the cartridge 2, and the tube 8 extends into the internal space S through the opening 2a and is guided by the guide groove 2b. Therefore, it is possible to prevent the tube 8 from hindering smooth relative movement between the cartridge 2 and the case 4 .

In the winding unit 6, the winding force _FW of the tube 8 is set so that the cartridge 2 can maintain the reference posture. Therefore, when the tube 8 is put in and taken out due to a change in the posture of the printer 1, the posture of the cartridge 2 does not change more than necessary. Therefore, the positional relationship between the liquid surface of the ink 30 and the other end 8b of the tube 8 is maintained, and good ejection characteristics of the printer 1 can be maintained.

Further, the winding unit 6 has a winding body 16, and a winding groove 16a is formed on the peripheral surface thereof. The tube 8 is wound by the winding unit 6 so as to fit in the winding groove 16a. Therefore, the tube 8 can be wound compactly by the winding unit 6, and the portability of the printer 1 can be maintained.

The bearing unit 5 also has a plurality of bearing balls 14 and a support member 15 that rotatably supports each bearing ball 14 . A plurality of bearing balls 14 are distributed on the outer surface of the cartridge 2 to support the outer surface of the cartridge 2 . The support member 15 rotatably supports each of the plurality of bearing balls 14 while maintaining the relative positions of the bearing balls 14 (distributed state of arrangement of the plurality of bearing balls 14). Thereby, smooth relative movement between the cartridge 2 and the case 4 can be realized.

Further, the case 4 supports the cartridge 2 inside by contacting the plurality of bearing balls 14 with the inner wall surface 4a. Therefore, the cartridge 2 and the case 4 can be smoothly and easily moved relative to each other in all directions along the outer surface of the cartridge 2 . Therefore, when the printer 1 is used, the ripples of the ink 30 can be effectively prevented, and the entry of air into the tube 8 can be prevented.

The printer 1 also includes a valve unit 13 and a communication channel R5 that communicates the valve unit 13 with the atmosphere. The valve unit 13 can switch the printer 1 between the first to third modes. Therefore, for example, it is possible to replenish the cartridge 2 with the ink 30 and maintain the ink head 7 without disassembling the printer 1, and the printing operation can be performed satisfactorily.

Next, a printer according to a modified example of this embodiment will be described. In the first modification, part of the other end 8b of the tube 8 is arranged vertically below the upper end of the weight 3 in the reference posture. At this time, the upper surface of the weight 3 does not have a flat surface, but has a partially formed concave portion. A portion of the other end 8b of the tube 8 may be positioned within this recess. As for the form of the concave portion, any one of a pit shape, a slit-like mortar shape, and the like may be employed. As a result, even when the remaining amount of ink 30 stored in the cartridge 2 is low, it is possible to more effectively prevent the air in the internal space S from entering the other end 8b of the tube 8 .

In a second modification, the other end 8b of the tube 8 does not need to be in contact with the lower portion of the cartridge 2. FIG. In this case, the other end 8b may face the lower portion of the cartridge 2 in the very vicinity. Effects similar to those of the first modification can be enjoyed.

Next, a third modified example will be described. In the present embodiment, as shown in FIG. 3, the other end of the tube 8 is bent in a direction substantially opposite to the extending direction of the guide groove 2b when viewed in the vertical direction. However, in the third modification, the bending direction of the other end is the extending direction of the guide groove 2b when viewed in the vertical direction. When it is assumed that the cartridge 2 is also slightly tilted due to the change in posture of the printer 1, the tilt direction follows the direction of the change in posture of the printer. The ink 30 is also biased in the same direction, but since the other end of the tube 8 is also bent and extended in the same direction, the ink 30 can be reliably supplied to the ink head 7 even if the remaining amount of the ink 30 is further reduced. . From a similar point of view, the other end of the tube 8 may be bent in the direction in which the guide groove 2b extends, and the other end 8b may be located near the inner wall of the cartridge 2 .

Other embodiments and the like will be described below, focusing on differences from the first embodiment.

(Second embodiment)
FIG. 7 is a schematic diagram of a printer according to the second embodiment. The internal space of the cartridge 102 is composed of a plurality of sub-spaces Sb that are partitioned for each different type of ink when viewed from the vertical direction. The ink 30 filled in each sub-space Sb is different in kind, for example, in color. The adjacent subspace Sb is separated by a partition wall 102e. The tube 8 is arranged for each subspace Sb, and can individually supply the ink 30 to the ink head 7 from the subspace Sb. A plurality of openings 102a through which the tubes 8 are individually inserted are provided in the upper portion of the cartridge 102 corresponding to each sub-space Sb.

All the partition walls 102e share a vertical line passing through the center of the cartridge 2. FIG. When viewed in the vertical direction, the weight 3 is arranged so that the same vertical line passes through the center of gravity and evenly straddles all the sub-spaces Sb.

Also in this configuration, the same effects as those of the first embodiment can be obtained. In addition, by using different types of ink 30, color printing can be performed on the surface of the printing object 40 in any orientation using a printer, for example.

The present invention is not limited to the above-described embodiments, and its configuration can be changed, added, or deleted without departing from the gist of the present invention.

As described above, the present invention is an excellent portable printing apparatus equipped with a cartridge, in which the position of the ink surface in the cartridge does not easily fluctuate when the orientation of the printing apparatus is changed during use, and good ejection characteristics can be maintained. have the same effect. Therefore, it would be beneficial to widely apply the present invention to portable printing devices that can exhibit the significance of this effect.

S Internal space Sb Subspace 1 Printer (portable printing device)
2, 102 cartridge 2a, 102a opening 2b guide groove 3 weight 4 case 4a inner wall surface 5 bearing unit 6 winding unit 7 ink head 7a nozzle surface 7b nozzle 8 tube 8a one end of tube 8b other end of tube 9 control unit 10 encoder 14 Bearing ball 15 Supporting member 16 Winding body 16a Winding groove 30 Ink

Claims (13)

a spherical cartridge having at least one internal space in which ink is stored;
a weight provided at the bottom of the cartridge in a reference posture, which is the posture of the cartridge in which the inclination with respect to the vertical direction is within a predetermined range;
a case that accommodates the cartridge;
a bearing unit disposed between the case and the cartridge and supporting the cartridge in all directions along the outer surface of the cartridge so that the cartridge can move relative to the case while maintaining the reference posture;
an ink head having a nozzle surface on which a plurality of nozzles are formed and supported by the case;
One end is connected to the ink head and extends into the internal space through the upper part of the cartridge in the standard posture, and the other end is arranged near the lower part of the cartridge to communicate the cartridge and the ink head. a tube that
and a control unit for controlling an ink ejecting operation of the ink head. 2. A portable printing device according to claim 1, wherein a portion of said other end of said tube abuts against a lower portion of said cartridge. 3. The portable printing apparatus according to claim 1, wherein a portion of said other end of said tube is arranged vertically below an upper end of said weight in said reference posture. a winding unit that winds up a surplus of the tube or feeds out a shortage of the tube according to a change in the distance between the ink head and the upper portion of the cartridge along the outer surface of the cartridge; A portable printing device according to any one of claims 1 to 3, comprising: 5. Portable printing according to claim 4, wherein a portion of the tube having a length corresponding to a change in distance between the ink head and the top of the cartridge is disposed between the case and the cartridge. Device. The upper portion of the cartridge is provided with an opening that communicates with the internal space,
A guide groove extending vertically from the opening is provided on the outer surface of the cartridge,
6. The portable printing apparatus according to claim 4, wherein the tube extends into the internal space through the opening, is guided by the guide groove, and is arranged by fitting into the guide groove. In the winding unit, when the cartridge is displaced from a state in which the short delivery amount of the tube is the minimum to a state in which the short delivery amount of the tube is the maximum, the other end of the tube and the cartridge The reference posture in which the change in the angle of intersection of the virtual straight line with the vertical line is 0° or more and 10° or less in a virtual plane formed by a virtual straight line connecting the rotation center and a vertical line passing through the rotation center. 7. The portable printing device according to any one of claims 4 to 6, wherein the winding force of the tube is set so that the cartridge can maintain a . The winding unit has a cylindrical winding body for spirally winding the tube, and a winding groove spirally winding around the axis of the winding body is formed on the peripheral surface of the winding body. is,
The portable printing apparatus according to any one of claims 4 to 7, wherein the tube is wound on the winding unit so as to fit in the winding groove. The bearing unit includes a plurality of bearing balls distributed along the outer surface of the cartridge and supporting the outer surface of the cartridge, and a bearing unit for the plurality of bearing balls while maintaining relative positions of the bearing balls. 9. The portable printing apparatus according to claim 1, further comprising a support member that rotatably supports each. 10. A portable printing device according to claim 9, wherein said case has a spherical inner wall surface that supports said cartridge by contacting said plurality of bearing balls. a valve unit provided in the middle of an ink flow path communicating between the cartridge and the ink head, and switching a communication destination with which the cartridge communicates;
a communication channel that communicates the outside with the valve unit,
The valve unit is
a first form in which a printing ink path is formed by communicating between the cartridge and the ink head, and the printing ink path is blocked from the outside;
a second form in which a purge ink path is formed by communicating between the ink head and the outside, and the purge ink path is blocked with respect to the cartridge;
a third embodiment in which a replenishment ink path is formed by communicating between the cartridge and the outside, and the replenishment ink path is blocked with respect to the ink head;
A portable printing device according to any one of claims 1 to 10, configured to be switchable between. the internal space of the cartridge is composed of a plurality of subspaces partitioned for each different type of ink when viewed from above in the vertical direction;
12. The portable printing apparatus according to any one of claims 1 to 11, wherein said tube is arranged so as to be able to supply said ink individually from said subspace to said ink head. An encoder that measures the relative movement distance between the ink head and the print object along the surface of the print object and transmits the measurement result to the control unit,
13. The portable printing apparatus according to claim 1, wherein said control unit controls said ejection operation of said ink head based on said relative movement distance.

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