JP5428652B2 - Printing device - Google Patents

Description

  The present invention relates to a printing apparatus.

  Conventionally, inkjet printers are known as printing apparatuses. This printer has a carriage holding a head for ejecting ink, and drives the head while the carriage is moving, thereby ejecting ink from nozzles to print an image on a medium such as paper.

  Some printers include a drive control unit that drives a head mounted on a carriage. In that case, in order to transmit a print signal from the printer main body to the drive control unit, the printer main body and the carriage are connected by a flexible flat cable (hereinafter also referred to as FFC) having high flexibility. In addition, power is supplied from the power supply unit on the printer body side to the drive control unit using another electric wire in the FFC.

  However, there is a demand for omitting the FFC because the FFC is likely to be a physical obstacle to the mechanism during the movement of the carriage, and the control signal such as the print signal is likely to get noise through the FFC.

  In this regard, Patent Document 1 discloses that a control signal such as a print signal is optically transmitted from the printer body to the carriage. Patent Document 2 discloses that a fuel cell is mounted on a carriage and power is supplied to a drive control unit of the carriage. And it is thought that FFC can be eliminated by combining these.

Japanese Patent Laid-Open No. 7-214869 JP 2005-219288 A

  However, in the latter power supply method of Patent Document 2, an increase in cost is inevitable as the fuel cell is mounted. In addition, a fuel cell requires a drainage mechanism to generate water after power generation, which also helps increase costs.

  The present invention has been made in view of the above-described conventional problems, and provides a printing apparatus that can supply power to a drive control unit of a carriage without using an FFC and can avoid an increase in cost. For the purpose.

The main invention for achieving the above object is:
A printing apparatus having a carriage having a head for ejecting ink, and printing the image on the medium by ejecting ink toward the medium by driving the head while the carriage moves.
A drive control unit provided on the carriage for driving the head with electric power;
A moving mechanism for moving the carriage,
The moving mechanism is
A power source that generates a force to move the carriage;
A conductive transmission member coupled to the power source and the carriage, and transmitting the force of the power source to the carriage to move the carriage;
The printing apparatus is characterized in that the electric power is supplied to the drive control unit through the conductive transmission member.

  Other features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

1 is a block diagram of a system configuration of a printer 1. FIG. 2 is a perspective view of an internal configuration of the printer 1. FIG. It is the longitudinal cross-sectional view. FIG. 4 is an arrangement diagram of nozzles of a head 41. 4 is an explanatory diagram of a head drive circuit 61 according to the head unit 40. FIG. FIG. It is explanatory drawing of the original signal ODRV, the print signal PRT (i), and the drive signal DRV (i).

  At least the following matters will become apparent from the description of the present specification and the accompanying drawings.

A printing apparatus having a carriage having a head for ejecting ink, and printing the image on the medium by ejecting ink toward the medium by driving the head while the carriage moves.
A drive control unit provided on the carriage for driving the head with electric power;
A moving mechanism for moving the carriage,
The moving mechanism is
A power source that generates a force to move the carriage;
A conductive transmission member coupled to the power source and the carriage, and transmitting the force of the power source to the carriage to move the carriage;
The printing apparatus, wherein the power is supplied to the drive control unit via the conductive transmission member.
According to such a printing apparatus, power is supplied to the drive control unit of the carriage via the conductive transmission member. Therefore, power can be supplied to the drive control unit without using an FFC, a fuel cell, or the like, and as a result, an increase in cost can be avoided.

Such a printing apparatus,
The power source is a motor;
The moving mechanism includes a pair of pulleys, and a timing belt wound around the pair of pulleys as the conductive transmission member,
The timing belt is fixed to the carriage;
One of the pair of pulleys is driven and rotated by the motor,
It is desirable to supply electric power to the drive control unit via at least one of the pair of pulleys and the timing belt.
According to such a printing apparatus, power is supplied to the drive control unit of the carriage via the timing belt. Therefore, power can be supplied to the drive control unit without using an FFC or a fuel cell, and as a result, an increase in cost can be avoided.

Such a printing apparatus,
The printing apparatus has a DC power source,
A portion of the one pulley that contacts and engages with the timing belt is formed to be conductive, and the portion that contacts and engages is electrically connected to a power supply terminal of the DC power supply. desirable.
According to such a printing apparatus, the power supply path to the drive control unit of the carriage is formed by the timing belt and the pulley, so that it is not necessary to use an FFC, a fuel cell, or the like.

Such a printing apparatus,
A guide rail for guiding the movement of the carriage;
The circuit board of the drive control unit has a power supply terminal related to the power supply, and a ground terminal,
The power supply terminal is electrically connected to the conductive transmission member,
The ground terminal is preferably electrically connected to the guide rail and electrically grounded through the guide rail.
According to such a printing apparatus, since the drive control unit is electrically grounded through the guide rail, it is not necessary to separately provide grounding wiring, and the apparatus configuration can be simplified.

=== Overall Configuration of Printing Apparatus 1 ===
Hereinafter, as a printing apparatus 1 according to the present embodiment, a serial ink jet printer (hereinafter referred to as printer 1) will be described as an example.

FIG. 1 is a block diagram of the system configuration of the printer 1. 2A is a perspective view of the internal configuration of the printer 1, and FIG. 3 is a longitudinal sectional view thereof.
The printer 1 includes a housing 3, a power supply unit 5, a controller 10, a transport unit 20, a carriage unit 30, and a head unit 40. The printer 1 is used by connecting to a computer 110 that is an external device, for example. That is, when print data is received from the computer 110, the printer 1 controls the units 20, 30, and 40 by the controller 10 and forms an image on the paper S as a medium. At that time, the situation in the printer 1 is monitored by the detector group 50, and the controller 10 controls each unit 20, 30, 40 based on the detection result.

  The housing 3 has a box body that accommodates the units 20, 30, and 40 as a main body, and has a mechanical frame 3 a made of a conductive material such as metal, for example.

  The power supply unit 5 is fixed to the housing 3. Then, it is connected to a household AC outlet or the like via an electric cord or the like, thereby functioning as a DC power source of 42 V or the like and supplying power to each unit 20, 30, 40. That is, the power supply unit 5 has a positive terminal of 42V as an output terminal for supplying power and a ground terminal that is electrically grounded via the mechanical frame.

  The controller 10 is also fixed to the housing 3. And it has the interface part 11, CPU12, the memory 13, and the unit control circuit 14. FIG. The interface unit 11 transmits and receives data between the computer 110 and the printer 1. The CPU 12 is an arithmetic processing unit that controls the entire printer 1, and controls each unit 20, 30, 40 via the unit control circuit 14. The memory 13 secures an area for storing a program of the CPU 12, a work area, and the like.

  The transport unit 20 feeds the paper S to a printable position and transports the paper S by a predetermined transport amount in the transport direction during printing. The paper feed roller 21, the transport motor 22, the transport roller 23, The platen 24 and the paper discharge roller 25 are provided. The paper feed roller 21 sends the paper S to be printed to the position of the transport roller 23. When the paper detection sensor 51, which is one of the detector groups 50, detects the leading edge of the paper S sent toward the transport roller 23, the controller 10 rotates the transport roller 23 to move the paper S to the print start position. Position to. When the paper S is positioned at the printing start position, at least some of the nozzles on the lower surface 41a of the head 41 are opposed to the paper S. The platen 24 is provided at a position that can face the lower surface 41a of the head 41, and supports the sheet S during printing from below.

  The carriage unit 30 reciprocally moves the head 41 in an intersecting direction (hereinafter referred to as a carriage moving direction) that intersects the transport direction, and includes a carriage 32 on which the head 41 is mounted and a guide rail 36 supported by the housing 3. A carriage motor 33 as a power source, pulleys 34a and 34b, and a timing belt 35. The guide rail 36 is, for example, a shaft that is long in the carriage movement direction, and engages with the carriage 32 to guide the carriage 32 so as to reciprocate along the carriage movement direction. The timing belt 35 is connected to the carriage motor 33 by pulleys 34 a and 34 b, and a part of the timing belt 35 is connected to the carriage 32, and the carriage 32 is reciprocated in the carriage movement direction by the drive rotation of the carriage motor 33. Move. As a result, the head 41 is reciprocated in the carriage movement direction with respect to the paper S.

  The pulleys 34a and 34b and the timing belt 35 also function as a power supply system for supplying power to a later-described head drive circuit 61 mounted on the carriage 32, which will be described later.

  The head unit 40 is mounted on the carriage 32. And it has the head 41 for discharging an ink drop to the paper S, and the head drive circuit 61 which drives the head 41 to discharge an ink drop from the nozzle of the head 41 (refer FIG. 5). A plurality of nozzles are provided on the lower surface 41a of the head 41. Each nozzle is provided with an ink chamber containing ink and a piezo element as a drive element for changing the volume of the ink chamber to eject ink droplets. It has been. Then, the head driving circuit 61 drives the piezo element based on a print signal PRT and the like described later, thereby ejecting ink droplets.

  Control signals for driving the head 41, such as the print signal PRT and the original signal generation parameters described later, are transmitted from the controller 10 to the head drive circuit 61 of the carriage 32 by an appropriate wireless communication device. Wirelessly transmitted. That is, the controller 10 is provided with a transmitter, and the carriage 32 is provided with a receiver. Then, when the receiver of the carriage 32 receives the radio wave transmitted from the transmitter of the controller 10, the head drive circuit 61 acquires the control signal.

  The detector group 50 includes a linear encoder 52, a rotary encoder 53, and the like. The linear encoder 52 detects the position of the carriage 32. The rotary encoder 53 detects the rotation amount of the transport roller 23.

  In the printer 1 having such a configuration, ink droplets are intermittently ejected from the head 41 moving along the carriage movement direction, and a dot forming operation for forming dots on the paper S and the paper S are conveyed in the conveyance direction. The transfer operation is repeated alternately. By doing so, a dot row is formed at a position different from the dot row (raster line) formed by the previous dot forming operation in the transport direction, and thus an image is completed on the paper S.

  The printer 1 can also perform bidirectional printing, that is, it can also form an image by ejecting ink droplets toward the paper S in the forward and backward paths in the carriage movement direction. In that case, the sheet S is transported between the forward and backward dot forming operations.

=== About the Head 41 and the Head Drive Circuit 61 ===
FIG. 4 is an arrangement diagram of the nozzles of the head 41. On the lower surface 41a of the head 41, a nozzle row 411 comprising a plurality of (for example, 180) nozzles # 1 to #n for each color of black (K), cyan (C), magenta (M), and yellow (Y). Is provided. The nozzles # 1 to #n of each nozzle row 411 are linearly aligned at a predetermined nozzle pitch P (for example, 180 dpi) along the transport direction of the paper S. Further, the nozzle rows 411 are arranged in parallel to each other with an interval in the carriage movement direction.

  FIG. 5 is an explanatory diagram of the head drive circuit 61 according to the head unit 40. A circuit board 61a of the head drive circuit 61 (corresponding to a drive control unit) is disposed in the carriage 32, and includes an original drive signal generating unit 63 and a drive signal shaping unit 65 as shown in FIG. Yes. Both are configured by an electric circuit.

  The head drive circuit 61 is provided for each nozzle row 411, that is, for each nozzle row 411 of each color of black (K), cyan (C), magenta (M), and yellow (Y). In addition, the piezo elements are individually driven for each nozzle. In the figure, the numbers in parentheses at the end of each signal name indicate the number of the nozzle to which the signal is supplied.

  When a voltage having a predetermined time width is applied between the electrodes provided at both ends of the piezoelectric element, the piezoelectric element expands according to the voltage application time and deforms the side wall of the ink flow path. As a result, the volume of the ink flow path contracts in accordance with the expansion and contraction of the piezo element, and the ink amount corresponding to the contraction is ejected from the nozzles # 1 to # 180 of the respective colors as ink droplets.

  As shown in FIG. 6, the original drive signal generation unit 63 is supplied with an original signal generation parameter that defines the waveform shape or the like of the original signal ODRV. Based on the original signal generation parameter, the original drive signal generation unit 63 generates an original signal ODRV that is used in common by the nozzles # 1 to #n. Here, the original signal ODRV has two pulses of a first pulse W1 and a second pulse W2, as shown in FIG. 7, within a period of one pixel (within a time during which the carriage 32 crosses the interval of one pixel). It is a signal containing.

  On the other hand, as shown in FIG. 6, the drive signal shaping unit 65 receives the original signal ODRV from the original drive signal generation unit 63 and the print signal PRT based on the print data. The print signal PRT is a signal corresponding to pixel data assigned to one pixel. That is, the print signal PRT is a signal corresponding to the pixel data included in the print data. Then, the drive signal shaping unit 65 blocks or passes the original signal ODRV for each nozzle (i) based on the print signal PRT (i) corresponding to each nozzle (i). For example, as shown in FIG. 7, when the print signal PRT (i) is a 2-bit signal “00”, both pulses W1 and W2 of the original signal ODRV are blocked, and the print signal PRT (i) In the case of “01”, only the pulse W1 is cut off and the pulse W2 is allowed to pass. In the case where the print signal PRT (i) is “10”, only the pulse W2 is cut off and the pulse W1 is allowed to pass. When the print signal PRT (i) is “11”, both pulses W1 and W2 are passed. Then, the passed pulse is output as a drive signal DRV (i) toward the piezoelectric element of each nozzle (i). The piezo element of each nozzle (i) is driven based on the drive signal DRV (i) from the drive signal shaping unit 65 to eject ink droplets.

=== Power Supply to the Head Drive Circuit 61 ===
The head drive circuit 61 described above is basically composed of an electric circuit and operates with electric power. The circuit board 61 a of the head driving circuit 61 is provided on the carriage 32. Therefore, normally, the power is supplied to the circuit board 61a by connecting the power supply unit 5 on the housing 3 side and the circuit board 61a on the carriage 32 side by a flexible flat cable (FFC).

  However, as described above, there is a demand for FFC-less. In this embodiment, as described above, the control signal is transmitted to the head drive circuit 61 by wireless transmission, that is, the FFC is not used for the transmission of the control signal. Therefore, if the power supply to the head drive circuit 61 can be performed by a method other than FFC, FFC-less can be achieved.

  Therefore, in the present embodiment, the pulleys 34 a and 34 b and the timing belt 35 related to the movement of the carriage 32 described above are also used as a power supply system to the head drive circuit 61. Details will be described below.

  As shown in FIG. 2, one pulley 34 a is provided at one end of the reciprocating path of the carriage 32. The other pulley 34b is fixed concentrically to the drive rotation shaft 33b of the carriage motor 33 provided at the other end of the reciprocating path. An endless timing belt 35 is wound around the pair of pulleys 34a and 34b, and a carriage 32 is connected to a part of the timing belt 35 via a connecting portion. The connecting portions are, for example, a pair of gripping members fixed on the carriage 32 side, and when the gripping members sandwich a part of the timing belt 35, the timing belt 35 and the carriage 32 are physically immovable relative to each other. It is connected. Accordingly, the driving force of the carriage motor 33 is transmitted to the carriage 32 via the timing belt 35, and thereby the carriage 32 is reciprocated.

  Here, a metal belt such as steel is used for the timing belt 35 as an example of the conductive transmission member. In addition, a peripheral surface portion of the pulley 34a that contacts and engages with the timing belt 35 is also formed of a conductive material such as metal, and further, the peripheral surface portion is electrically connected to the positive terminal of the power supply unit 5. Connected brush members are in sliding contact.

  Therefore, as shown in FIG. 5, the power supply terminal 62 </ b> P (for example, the positive terminal) of the circuit board 61 a of the head drive circuit 61 is extended to the connection portion of the timing belt 35 and electrically connected to the timing belt 35. At the same time, the ground terminal 62G of the circuit board 61a is electrically grounded via the mechanical frame 3a or the like of the housing 3 to form a power supply system to the head drive circuit 61.

  In the above example, the power supply unit 5 is connected to the pulley 34a that is driven and rotated by the timing belt 35, and thereby the power is supplied to the head drive circuit 61 via the driven pulley 34a. Instead, the power supply unit 5 may be connected to the pulley 34b that is driven and rotated by the carriage motor 33, and power may be supplied to the head drive circuit 61 via the drive pulley 34b. However, in either case, the pulley (34a or 34b) that is not connected to the power supply unit 5 is preferably formed of an insulating material.

  Further, if necessary, a DC-DC converter 67 is provided as in the illustrated example, whereby the voltage of the power supply unit 5 is changed to an appropriate voltage (3.3 V in the illustrated example) required by the head drive circuit 61. You may transform and supply power.

  Furthermore, as a method of electrically grounding the ground terminal 62G of the head drive circuit 61, the guide rail 36 may be used. That is, a conductive portion is provided on at least a part of the guide rail 36 over substantially the entire length of the guide rail 36, and the ground terminal 62G of the head drive circuit 61 is slid on the conductive portion via a brush member or the like. In addition, the conductive portion may be electrically connected to the mechanical frame 3a of the housing 3 and grounded.

=== Other Embodiments ===
The above-described embodiments are for facilitating the understanding of the present invention, and are not intended to limit the present invention. The present invention can be changed and improved without departing from the gist thereof, and it is needless to say that the present invention includes equivalents thereof. In particular, the embodiments described below are also included in the present invention.

In the above-described embodiment, a method using radio waves is used as a method of wirelessly transmitting a control signal such as the print signal PRT from the controller 10 to the head drive circuit 61 of the carriage 32. However, the method is not limited to this as long as wireless transmission is possible. It is not a thing. For example, the control signal may be transmitted optically. That is, the laser irradiation unit may be provided on the controller 10 side, the photoelectric conversion unit may be provided on the carriage 32 side, and the control signal may be transmitted as laser light from the laser irradiation unit to the photoelectric conversion unit. In this case, the laser beam from the laser irradiation unit is irradiated in parallel with the carriage movement direction. Accordingly, the laser irradiation unit can irradiate the photoelectric conversion unit with laser light over the entire range of the reciprocation path of the carriage 32.
In the above-described embodiment, the metal belt is used as the conductive transmission member. However, the present invention is not limited to this, and a conductive chain may be used. In this case, a pair of sprockets is used instead of the pair of pulleys 34a and 34b described above.

  In the above-described embodiment, the piezoelectric effect method using a piezo element is exemplified as the ink discharge method. However, the present invention is not limited to this. For example, the ink is heated from the nozzles by bubbles generated in the ink. A thermal jet method may be used.

1 Printer (printing device),
3 Housing, 3a Mechanical frame,
5 Power supply unit,
10 controller, 11 interface section,
13 memory, 14 unit control circuit,
20 transport units, 21 paper feed rollers, 22 transport motors, 23 transport rollers,
24 platen, 25 paper discharge roller,
30 carriage unit, 32 carriage,
33 Carriage motor (power source, motor), 33b Drive rotating shaft,
34a pulley, 34b pulley, 35 timing belt (conductive transmission member),
36 guide rails,
40 head unit, 41 head, 41a bottom surface,
50 detector groups, 51 paper detection sensors,
52 linear encoder, 53 rotary encoder,
61 head drive circuit (drive control unit), 61a circuit board,
62G ground terminal, 62P power supply terminal,
63 original drive signal generation unit, 65 drive signal shaping unit, 67 DC-DC converter,
110 computers,
411 nozzle rows,
S paper

Claims (3)

A printing apparatus having a carriage having a head for ejecting ink, and printing the image on the medium by ejecting ink toward the medium by driving the head while the carriage moves.
A drive control unit provided on the carriage for driving the head with electric power;
A moving mechanism for moving the carriage,
The moving mechanism is
A pair of pulleys;
A motor for generating a force to move the carriage;
Looped around said pair of pulleys, is secured to the carriage, coupled to said with the motor carriage, made of a conductive transmission member for moving said carriage to transmit the force of the motor to the carriage timing A belt, and
One of the pair of pulleys is driven and rotated by the motor, and the electric power is supplied to the drive control unit via at least one of the pair of pulleys and the timing belt. Printing device. The printing apparatus according to claim 1 ,
The printing apparatus has a DC power source,
A portion of the one pulley that contacts and engages with the timing belt is formed to be conductive, and the portion that contacts and engages is electrically connected to a power supply terminal of the DC power supply. Characteristic printing device. The printing apparatus according to any one of claims 1 to 2,
A guide rail for guiding the movement of the carriage;
The circuit board of the drive control unit has a power supply terminal related to the power supply, and a ground terminal,
The power supply terminal is electrically connected to the conductive transmission member,
The printing apparatus, wherein the ground terminal is electrically connected to the guide rail and is electrically grounded through the guide rail.

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