Printing device

Abstract

To suppress a foreign matter from intruding into a substrate case.SOLUTION: A printing device is provided with: a substrate case in which a substrate is stored; a first duct extended in a first direction, to which gas is supplied through an opening; a second duct communicated with the first duct and extended in a second direction crossing the first direction; and a first fan that supplies gas from the second duct into the substrate case. The first fan supplies gas in a direction that is different from the first direction and the second direction.SELECTED DRAWING: Figure 11

Description

[Technical field]

[0001] The present invention relates to a printing device. [Background technology]

[0002] Various techniques have been proposed for cooling a substrate provided in a printing device such as an inkjet printer. For example, Patent Document 1 discloses a printing device that includes a substrate and a substrate case that houses the substrate, and that cools the substrate by introducing gas into the substrate case through an opening provided in the substrate case. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-215525 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, according to the conventional technology, since gas is taken directly into the inside of the substrate case through an opening provided in the substrate case, there is a possibility that foreign matter may enter the inside of the substrate case. [Means for solving the problem]

[0005] In order to solve the above problems, the printing device of the present invention comprises a substrate case in which a substrate is housed, a first duct extending in a first direction to which gas is supplied through an opening, a second duct communicating with the first duct and extending in a second direction intersecting the first direction, and a first fan that supplies gas from the second duct to the inside of the substrate case, and is characterized in that the direction in which the first fan supplies gas is different from the first direction and the second direction. [Brief description of the drawings]

[0006] [Figure 1]FIG. 1 is a block diagram showing an example of the configuration of an inkjet printer 1 according to an embodiment of the invention. [Diagram 2] FIG. 1 is a perspective view showing an example of a schematic internal structure of an inkjet printer 1. [Diagram 3] 13 is a cross-sectional view illustrating an example of the structure of a discharge section D[q][m]. [Figure 4] FIG. 2 is a block diagram showing an example of the configuration of a head unit HU[q]. [Diagram 5] 13 is a timing chart illustrating an example of a signal supplied to a head unit HU[q]. [Figure 6] FIG. 11 is an explanatory diagram for explaining an example of the operation of the connection state specification circuit SCC[q]. [Figure 7] 13 is a block diagram showing an example of the configuration of a drive signal generation circuit GR-N[q]. FIG. [Figure 8] 2 is a perspective view showing an example of a schematic structure of a board unit including a board case 8. FIG. [Figure 9] FIG. 2 is a perspective view showing an example of a schematic structure of a substrate unit. [Figure 10] FIG. 2 is a perspective view showing an example of a schematic structure of a substrate unit. [Figure 11] FIG. 2 is a cross-sectional view showing an example of a schematic structure of a substrate unit. [Figure 12] FIG. 2 is a cross-sectional view showing an example of a schematic structure of a substrate unit. [Figure 13] 1 is a plan view showing an example of the arrangement of electronic components on a drive circuit board 400. FIG. [Figure 14] FIG. 2 is a cross-sectional view showing an example of a schematic structure of a substrate unit. [Figure 15] 13 is a perspective view showing an example of a schematic structure of a substrate case 8B according to Modification 2. FIG. [Figure 16] 11 is a cross-sectional view showing an example of a schematic structure of a board unit including a board case 8B according to Modification 2. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. However, in each figure, the dimensions and scales of each part are appropriately different from the actual ones. Further, since the embodiments described below are preferred specific examples of the present invention, various technically preferable limitations are imposed. However, the scope of the present invention is not limited to these embodiments unless otherwise specified in the following description to limit the present invention specifically.

[0008] <<A. Embodiment>> In this embodiment, an inkjet printer 1 that ejects ink to form an image on a recording paper PP will be exemplified to describe the printing apparatus.

[0009] <<1. Outline of Inkjet Printer>> Hereinafter, with reference to FIGS. 1 to 3, an example of the configuration of the inkjet printer 1 according to this embodiment will be described.

[0010] FIG. 1 is a functional block diagram showing an example of the configuration of the inkjet printer 1.

[0011] As shown in FIG. 1, print data Img indicating an image to be formed by the inkjet printer 1 is supplied to the inkjet printer 1 from a host computer such as a personal computer or a digital camera. The inkjet printer 1 executes a printing process of forming the image indicated by the print data Img supplied from the host computer on the recording paper PP.

[0012] As shown in FIG. 1, the inkjet printer 1 includes a control module 2 that controls each part of the inkjet printer 1, a head module 3 including a head unit HU provided with a discharge unit D that discharges ink, a drive signal generation module 4 that generates a drive signal Com for driving the discharge unit D, a power supply module 6 that supplies power to each part of the inkjet printer 1, and a conveyance module 7 that changes the relative position of the recording paper PP with respect to the head module 3.

[0013] In this embodiment, the inkjet printer 1 is an example of a "printing device," and ink is an example of a "liquid."

[0014] In this embodiment, the head module 3 has Q head units HU. Here, the value Q is a natural number equal to or greater than 1. Below, the q-th head unit HU of the Q head units HU is referred to as head unit HU[q]. Here, the variable q is a natural number that satisfies 1≦q≦Q. Also, below, when a component or signal of the inkjet printer 1 corresponds to head unit HU[q] of the Q head units HU, the subscript [q] may be added to the symbol representing the component or signal.

[0015] The control module 2 is configured to include one or more CPUs (Central Processing Units). However, the control module 2 may include a programmable logic device such as an FPGA (field-programmable gate array) instead of or in addition to a CPU. The control module 2 is also configured to include a memory. The memory is configured to include one or both of a volatile memory such as a RAM (Random Access Memory) and a non-volatile memory such as a ROM (Read Only Memory), an EEPROM (Electrically Erasable Programmable Read-Only Memory), or a PROM (Programmable ROM).

[0016] The control module 2 generates signals for controlling the operation of each part of the inkjet printer 1, such as a specification signal SI and a waveform specification signal dCom.

[0017] Here, the waveform designation signal dCom is a digital signal that defines the waveform of the drive signal Com. The drive signal Com is an analog signal for driving the discharge sections D.

[0018] In this embodiment, it is assumed that the drive signal Com includes Q drive signals Com[1] to Com[Q] that correspond one-to-one to the Q head units HU[1] to HU[Q]. Of these, the drive signal Com[q] drives the discharge section D provided in the head unit HU[q]. Note that in this embodiment, it is assumed that the drive signal Com[q] includes a drive signal Com-A[q] and a drive signal Com-B[q]. In the following, the drive signal Com-A[q] and the drive signal Com-B[q] may be collectively referred to as the drive signal Com-N[q].

[0019] In this embodiment, it is assumed that the drive signal generation module 4 includes Q drive signal generation units GR[1] to GR[Q] that correspond one-to-one to the Q head units HU[1] to HU[Q]. Of these, the drive signal generation unit GR[q] includes a drive signal generation circuit GR-A[q] that generates a drive signal Com-A[q], and a drive signal generation circuit GR-B[q] that generates a drive signal Com-B[q]. In the following, the drive signal generation circuit GR-A[q] and the drive signal generation circuit GR-B[q] may be collectively referred to as the drive signal generation circuit GR-N[q].

[0020] In this embodiment, the waveform designation signal dCom includes Q waveform designation signals dCom[1] to dCom[Q] that correspond one-to-one to the Q head units HU[1] to HU[Q]. Among these, the waveform designation signal dCom[q] includes a waveform designation signal dCom-A[q] that defines the waveform of the drive signal Com-A[q], and a waveform designation signal dCom-B[q] that defines the waveform of the drive signal Com-B[q]. In the following, the waveform assignment signal dCom-A[q] and the waveform assignment signal dCom-B[q] may be collectively referred to as the waveform assignment signal dCom-N[q]. In this embodiment, the drive signal generating circuit GR-N[q] generates a drive signal Com-N[q] having a waveform indicated by the waveform assignment signal dCom-N[q] based on the waveform assignment signal dCom-N[q].

[0021] The designation signal SI is a digital signal that designates the type of operation of each ejection section D provided in the head module 3. Specifically, the designation signal SI designates whether or not to supply the drive signal Com to the ejection section D, thereby designating the type of operation of the ejection section D, such as whether or not to eject ink from the ejection section D.

[0022] In this embodiment, it is assumed that the designation signal SI includes Q designation signals SI[1] to SI[Q] that correspond one-to-one to the Q head units HU[1] to HU[Q]. Among these, the designation signal SI[q] designates the type of operation of the discharge section D provided in the head unit HU[q].

[0023] When a printing process is performed, the control module 2 generates a signal, such as a designation signal SI, for controlling the head module 3 based on the print data Img. When a printing process is performed, the control module 2 also generates a signal, such as a waveform designation signal dCom, for controlling the drive signal generating module 4. When a printing process is performed, the control module 2 also generates a signal for controlling the transport module 7. In this way, during the printing process, the control module 2 controls the transport module 7 so as to change the relative position of the recording paper PP with respect to the head module 3, while adjusting the presence or absence of ink ejection from the ejection unit D and the timing of ink ejection, and controls each part of the inkjet printer 1 so that an image corresponding to the print data Img is formed on the recording paper PP.

[0024] As shown in FIG. 1, the head unit HU[q] includes a supply circuit SC[q] and a recording head HD[q].

[0025] The recording head HD[q] has M discharge units D. Here, the value M is a natural number equal to or greater than 1. In the following, the m-th discharge unit D of the M discharge units D provided in the recording head HD[q] may be referred to as a discharge unit D[q][m]. Here, the variable m is a natural number that satisfies 1≦m≦M. In the following, when a component or signal of the inkjet printer 1 corresponds to the m-th discharge unit D of the M discharge units D provided in each head unit HU, the subscript [m] may be added to the symbol for representing the component or signal. In the following, when a component or signal of the inkjet printer 1 corresponds to the discharge unit D[q][m] provided in the head unit HU[q], the subscript [q][m] may be added to the symbol for representing the component or signal.

[0026] The supply circuit SC[q] switches whether to supply the drive signal Com[q] including the drive signal Com-A[q] and the drive signal Com-B[q] to the discharge section D[m] based on the designation signal SI[q]. Hereinafter, the drive signal Com[q] that is supplied to the discharge section D[q][m] may be referred to as the supply drive signal Vin[q][m].

[0027] In the following, a case where the value Q is "4" will be described as an example. In this embodiment, the drive signal generation circuit GR-N[q] is an example of a "generation circuit", and the head unit HU[q] is an example of a "liquid ejection head".

[0028] FIG. 2 is a perspective view showing an example of a schematic internal structure of the inkjet printer 1. As shown in FIG.

[0029] 2, this embodiment assumes that the inkjet printer 1 is a serial printer. Specifically, when executing a printing process, the inkjet printer 1 transports the recording paper PP in the Y1 direction, while reciprocating the head module 3 in the X1 direction that intersects with the Y1 direction, and the X2 direction that is the opposite direction to the X1 direction, to eject ink from the ejection section D[m], thereby forming dots Dt on the recording paper PP according to the print data Img.

[0030] Hereinafter, the X1 direction and its opposite X2 direction are collectively referred to as the "X-axis direction", the Y1 direction intersecting the X-axis direction and its opposite Y2 direction are collectively referred to as the "Y-axis direction", and the Z1 direction intersecting the X-axis direction and the Y-axis direction and its opposite Z2 direction are collectively referred to as the "Z-axis direction". In this embodiment, as an example, a case will be described in which the X-axis direction, the Y-axis direction, and the Z-axis direction are orthogonal to each other. However, the present invention is not limited to this aspect. It is sufficient that the X-axis direction, the Y-axis direction, and the Z-axis direction intersect each other. In this embodiment, the Z2 direction is the direction in which ink is ejected from the ejection section D[q][m].

[0031] As shown in FIG. 2, the inkjet printer 1 according to this embodiment includes a housing 100, a carriage 110 that is capable of reciprocating in the X-axis direction within the housing 100 and that carries a head module 3 including Q head units HU, and a substrate case 8 that houses various substrates.

[0032] 2, it is assumed that the carriage 110 stores Q ink cartridges 120 in one-to-one correspondence with Q colors of ink including cyan, magenta, yellow, and black. Furthermore, it is assumed in this embodiment that the inkjet printer 1 includes Q head units HU[1] to HU[Q] in one-to-one correspondence with the Q ink cartridges 120, as described above. The ejection section D[q][m] provided in the head unit HU[q] receives ink from the ink cartridge 120 corresponding to the head unit HU[q]. This allows the ejection section D[q][m] to fill itself with the supplied ink, and eject the ink from the nozzles N[q][m] provided in the ejection section D[q][m]. Note that the ink cartridge 120 may be provided outside the carriage 110.

[0033] As described above, the inkjet printer 1 according to this embodiment also includes a transport module 7. As shown in Fig. 2, the transport module 7 includes a carriage transport mechanism 71 for reciprocating the carriage 110 in the X-axis direction, a carriage guide shaft 76 that supports the carriage 110 so that it can reciprocate in the X-axis direction, a medium transport mechanism 73 for transporting the recording paper PP, and a platen 75 provided in the Z2 direction of the carriage 110. Thus, when a printing process is performed, the transport module 7 causes the carriage transport mechanism 71 to reciprocate the head module 3 together with the carriage 110 along the carriage guide shaft 76 in the X-axis direction, and the medium transport mechanism 73 to transport the recording paper PP on the platen 75 in the Y1 direction, thereby changing the relative position of the recording paper PP with respect to the head module 3 and enabling ink to land on the entire recording paper PP.

[0034] FIG. 3 is a schematic partial cross-sectional view of the recording head HD[q], in which the recording head HD[q] is cut so as to include the discharge portion D[q][m].

[0035] 3, the ejection section D[q][m] includes a piezoelectric element PZ[q][m], a cavity CV[q][m] filled with ink, a nozzle N[q][m] communicating with the cavity CV[q][m], and a vibration plate 321. The ejection section D[q][m] ejects ink from inside the cavity CV[q][m] from the nozzle N[q][m] when the piezoelectric element PZ[q][m] is driven by a supply drive signal Vin[q][m].

[0036] The cavity CV[q][m] is a space defined by the cavity plate 324, the nozzle plate 323 in which the nozzle N[q][m] is formed, and the vibration plate 321. The cavity CV[q][m] communicates with the reservoir 325 via the ink supply port 326. The reservoir 325 communicates with the ink cartridge 120 corresponding to the head unit HU[q] in which the ejection portion D[q][m] is provided, via the ink intake port 327.

[0037] The piezoelectric element PZ[q][m] has an upper electrode Zu[q][m], a lower electrode Zd[q][m], and a piezoelectric body Zm[q][m] provided between the upper electrode Zu[q][m] and the lower electrode Zd[q][m]. The lower electrode Zd[q][m] is electrically connected to a power supply line Ld[q] set to a predetermined potential VBS. When a supply drive signal Vin[q][m] is supplied to the upper electrode Zu[q][m] and a voltage is applied between the upper electrode Zu[q][m] and the lower electrode Zd[q][m], the piezoelectric element PZ[q][m] is displaced in the Z1 direction or the Z2 direction according to the applied voltage, and as a result, the piezoelectric element PZ[q][m] vibrates. The lower electrode Zd[q][m] is joined to the vibration plate 321. Therefore, when the piezoelectric element PZ[q][m] is driven to vibrate by the supply drive signal Vin[q][m], the vibration plate 321 also vibrates. The vibration of the vibration plate 321 changes the volume of the cavity CV[q][m] and the pressure inside the cavity CV[q][m], and the ink filled in the cavity CV[q][m] is ejected from the nozzle N[q][m].

[0038] <<2. Head unit overview>> Hereinafter, an overview of the head unit HU will be described with reference to FIGS.

[0039] FIG. 4 is a block diagram showing an example of the configuration of the head unit HU[q].

[0040] 4, the head unit HU[q] includes a supply circuit SC[q] and a recording head HD[q]. The head unit HU[q] also includes a wiring La[q] to which a drive signal Com-A[q] is supplied from a drive signal generating circuit GR-A[q], and a wiring Lb[q] to which a drive signal Com-B[q] is supplied from a drive signal generating circuit GR-B[q].

[0041] The supply circuit SC[q] includes M switches Wa[q][1] to Wa[q][M] that correspond one-to-one to the M discharge sections D[q][1] to D[q][M], M switches Wb[q][1] to Wb[q][M] that correspond one-to-one to the M discharge sections D[q][1] to D[q][M], and a connection state designation circuit SCC[q] that designates the connection state of each switch. The connection state designation circuit SCC[q] generates a connection state designation signal Ra[q][m] that designates the on / off state of the switch Wa[q][m], and a connection state designation signal Rb[q][m] that designates the on / off state of the switch Wb[q][m], based on the designation signal SI[q] and the latch signal LAT supplied from the control module 2.

[0042] The switch Wa[q][m] switches between electrical continuity and non-conduction between the wiring La[q] and the upper electrode Zu[q][m] of the piezoelectric element PZ[q][m] based on the connection state designation signal Ra[q][m]. In this embodiment, the switch Wa[q][m] is turned on when the connection state designation signal Ra[q][m] is at a high level, and turned off when the connection state designation signal Ra[q][m] is at a low level. When the switch Wa[q][m] is turned on, the drive signal Com-A[q] supplied to the wiring La[q] is supplied to the upper electrode Zu[q][m] of the discharge section D[q][m] as the supply drive signal Vin[q][m].

[0043] The switch Wb[q][m] switches between electrical continuity and non-conduction between the wiring Lb[q] and the upper electrode Zu[q][m] of the piezoelectric element PZ[q][m] based on the connection state designation signal Rb[q][m]. In this embodiment, the switch Wb[q][m] is turned on when the connection state designation signal Rb[q][m] is at a high level, and turned off when the connection state designation signal Rb[q][m] is at a low level. When the switch Wb[q][m] is turned on, the drive signal Com-B[q] supplied to the wiring Lb[q] is supplied to the upper electrode Zu[q][m] of the discharge section D[q][m] as the supply drive signal Vin[q][m].

[0044] When the inkjet printer 1 executes a printing process, a number of unit periods TP are set as the operating period of the inkjet printer 1. During each unit period TP, the inkjet printer 1 can drive each ejection section D for the printing process.

[0045] FIG. 5 is a timing chart showing an example of various signals such as the drive signal Com supplied to the head module 3 in the unit period TP.

[0046] 5, the control module 2 outputs a latch signal LAT having a plurality of pulses PLL, whereby the control module 2 defines a unit period TP as a period from the rising edge of a pulse PLL to the rising edge of the next pulse PLL.

[0047] As shown in FIG. 5, the designation signal SI[q] includes M individual designation signals Sd[q][1] to Sd[q][M] that correspond one-to-one to the M discharge sections D[q][1] to D[q][M]. When the inkjet printer 1 executes a printing process, the individual designation signal Sd[q][m] designates the driving mode of the discharge section D[q][m] in each unit period TP. Prior to each unit period TP, the control module 2 supplies the designation signal SI[q] including the M individual designation signals Sd[q][1] to Sd[q][M] to the connection state designation circuit SCC[q] in synchronization with the clock signal CL. Then, the connection state designation circuit SCC[q] generates a connection state designation signal Ra[q][m] and a connection state designation signal Rb[q][m] based on the individual designation signal Sd[q][m] during the unit period TP.

[0048] In this embodiment, the individual designation signal Sd[q][m] can take any one of three values ​​during the unit period TP in which the printing process is executed: a value of "1" that designates the discharge section D[q][m] as a large dot-forming discharge section DP1; a value of "2" that designates the discharge section D[q][m] as a small dot-forming discharge section DP2; and a value of "3" that designates the discharge section D[q][m] as a non-dot-forming discharge section DN.

[0049] Here, the large dot-forming discharge unit DP1 is a discharge unit D that discharges ink from a nozzle N[q][m] during the unit period TP to form a large dot Dt1 on the recording paper PP. The small dot-forming discharge unit DP2 is a discharge unit D that discharges ink from a nozzle N[q][m] during the unit period TP to form a small dot Dt2 that is smaller than the large dot Dt1 on the recording paper PP. The non-dot-forming discharge unit DN is a discharge unit D that does not discharge ink from the nozzle N[m] during the unit period TP and does not form a dot on the recording paper PP.

[0050] 5, the driving signal Com-A[q] has a waveform PA provided for each unit period TP. Here, the waveform PA is a waveform that, in each unit period TP, goes from a reference potential V0, through a potential VL1 lower than the reference potential V0, and a potential VH1 higher than the reference potential V0, and then returns to the reference potential V0. The waveform PA is determined so that when a supply driving signal Vin[q][m] having the waveform PA is supplied to the ejection section D[q][m], ink equivalent to a large dot Dt1 is ejected from the ejection section D[q][m].

[0051] Moreover, the driving signal Com-B[q] has a waveform PB provided in each unit period TP. Here, the waveform PB is a waveform that changes from a reference potential V0, through a potential VL2 lower than the reference potential V0, and a potential VH2 higher than the reference potential V0, and then returns to the reference potential V0 in each unit period TP. The waveform PB is determined so that when the supply driving signal Vin[q][m] having the waveform PB is supplied to the ejection section D[q][m], ink equivalent to a small dot Dt2 is ejected from the ejection section D[q][m].

[0052] In this embodiment, as an example, when the potential of the supply drive signal Vin[q][m] supplied to the discharge section D[q][m] is high, the volume of the cavity CV[q][m] of the discharge section D[q][m] is assumed to be smaller than when the potential is low. Therefore, when the discharge section D[q][m] is driven by the supply drive signal Vin[q][m] having the waveform PA or the waveform PB, the potential of the supply drive signal Vin[q][m] changes from low to high, causing the ink in the discharge section D[q][m] to be discharged from the nozzle N[q][m].

[0053] FIG. 6 is an explanatory diagram showing an example of the operation of the connection state specification circuit SCC[q].

[0054] 6, when the individual designation signal Sd[q][m] indicates a value "1" that designates the discharge section D[q][m] as a large dot forming discharge section DP1 during the unit period TP, the connection state designation circuit SCC[q] sets the connection state designation signal Ra[q][m] to a high level during the unit period TP. In this case, the switch Wa[q][m] is turned on during the unit period TP. Therefore, during the unit period TP, the discharge section D[q][m] is driven by the supply drive signal Vin[q][m] having the waveform PA, and discharges an amount of ink equivalent to the large dot Dt1.

[0055] Furthermore, when the individual designation signal Sd[q][m] indicates a value of "2" that designates the discharge section D[q][m] as the small dot forming discharge section DP2 during the unit period TP, the connection state designation circuit SCC[q] sets the connection state designation signal Rb[q][m] to a high level during the unit period TP. In this case, the switch Wb[q][m] is turned on during the unit period TP. Therefore, during the unit period TP, the discharge section D[q][m] is driven by the supply drive signal Vin[q][m] having the waveform PB, and discharges an amount of ink equivalent to the small dot Dt2.

[0056] Furthermore, when the individual designation signal Sd[m] indicates a value "3" that designates the discharge section D[q][m] as a dot non-forming discharge section DN during the unit period TP, the connection state designation circuit SCC[q] sets the connection state designation signal Ra[q][m] and the connection state designation signal Rb[q][m] to a low level during the unit period TP. In this case, the switch Wa[q][m] and the switch Wb[q][m] are turned off during the unit period TP. Therefore, the discharge section D[q][m] is not driven by the supply drive signal Vin[q][m] during the unit period TP, and does not discharge ink.

[0057] <<3. Drive signal generation circuit>> Hereinafter, an overview of the drive signal generation circuit GR-N[q] will be described with reference to FIG.

[0058] FIG. 7 is a diagram showing an example of a circuit configuration of the drive signal generation circuit GR-N[q].

[0059] As shown in Figure 7, the drive signal generating circuit GR-N[q] includes an integrated circuit 40, an amplifier circuit 41, a smoothing circuit 42, a pull-up circuit 43, and a filter circuit 44, and generates a drive signal Com-N[q] based on a waveform designation signal dCom-N[q].

[0060] The integrated circuit 40 is, for example, an LSI, i.e., a Large Scale Integration, and generates the gate signal SGH and the gate signal SGL based on the waveform designation signal dCom-N[q]. The integrated circuit 40 includes an analog conversion circuit 410, a subtractor 404, an adder 406, an attenuator 408, an integral attenuator 412, a comparator 420, and a gate driver 430.

[0061] The analog conversion circuit 410 is a DAC, i.e., a digital to analog converter, and converts the digital waveform designation signal dCom-N[q] into an analog signal Aa. The voltage amplitude of the signal Aa is, for example, about 0 to 2 volts, and this voltage is amplified by about 20 times to become the drive signal Com-N[q]. In other words, the signal Aa is the signal before amplification of the drive signal Com-N[q]. The integral attenuator 412 attenuates and integrates a signal SN1 input to a terminal Tn1, which will be described later, to output a signal Ax. The subtractor 404 outputs a signal Ab indicating the potential obtained by subtracting the potential of the signal Aa from the potential of the signal Ax. The attenuator 408 outputs a signal Ay obtained by attenuating the high frequency components of a signal SN2 input to a terminal Tn2, which will be described later. The adder 406 outputs a signal As indicating a potential obtained by adding the potential of the signal Ab and the potential of the signal Ay.

[0062] The comparator 420 outputs a modulated signal Ms obtained by pulse-modulating the signal As. Specifically, the comparator 420 outputs a modulated signal Ms that goes to H level when the signal As is at or above a threshold voltage Vth1 if the signal As is at a voltage rise, and goes to L level when the signal As is below a threshold voltage Vth2 if the signal As is at a voltage fall. The threshold voltages Vth1 and Vth2 are set to have a relationship of "Vth1>Vth2." The power supply voltage of the circuit from the analog conversion circuit 410 to the comparator 420 is a low voltage such as 3.3 volts. In contrast, the drive signal Com-N[q] has a large amplitude, and may exceed 40 volts, for example. For this reason, the integral attenuator 412 attenuates the signal SN1 having an amplitude corresponding to the drive signal Com-N[q], so that the amplitude range of the signal Ax matches the amplitude range of the signal in the circuit from the analog conversion circuit 410 to the comparator 420. In addition, in this embodiment, a digital signal is used as an example of the waveform assignment signal dCom-N[q], but the waveform assignment signal dCom-N[q] may be any signal that specifies a target value for generating the drive signal Com-N[q], and may be, for example, an analog signal Aa. When the signal Aa is the waveform assignment signal dCom-N[q], the integrated circuit 40 may be configured without including the analog conversion circuit 410.

[0063] The gate driver 430 converts the modulated signal Ms to a specific amplitude to generate a gate signal SGH, and outputs the converted signal to a terminal TnH. The gate driver 430 also converts the inverted logical level of the modulated signal Ms to a specific amplitude to generate a gate signal SGL, and outputs the converted signal to a terminal TnL.

[0064] The amplifier circuit 41 includes, for example, a high-side transistor TrH and a low-side transistor TrL, and generates an amplified signal Az that is an amplified signal of the modulated signal Ms, based on the gate signals SGH and SGL output from the integrated circuit 40. Note that in this embodiment, as an example, it is assumed that the transistors TrH and TrL are N-channel type field effect transistors.

[0065] A gate signal SGH output from the gate driver 430 is input to the gate electrode of the transistor TrH via a terminal TnH and a resistor RGH. A gate signal SGL output from the gate driver 430 is input to the gate electrode of the transistor TrL via a terminal TnL and a resistor RGL.

[0066] The logic levels of the gate signals SGH and SGL are mutually exclusive. Here, "mutually exclusive" means that the signal level of the gate signal SGH supplied to the gate electrode of the transistor TrH and the signal level of the gate signal SGL supplied to the gate electrode of the transistor TrL are never at high level at the same time, in other words, the transistors TrH and TrL are never on at the same time. The transistor TrH is on when the gate electrode of the transistor TrH is at high level, and is off when the gate electrode of the transistor TrH is at low level. The transistor TrL is on when the gate electrode of the transistor TrL is at high level, and is off when the gate electrode of the transistor TrL is at low level.

[0067] The drain electrode of the transistor TrH is electrically connected to a power supply line set to a high-potential side power supply potential VHV, and the source electrode is electrically connected to a node Nd. The source electrode of the transistor TrL is electrically connected to a power supply line set to a ground potential, and the drain electrode is electrically connected to the node Nd. Note that the ground potential is lower than the power supply potential VHV.

[0068] As described above, the transistor TrH is turned on when the gate signal SGH supplied to the gate electrode is at a high level, and turned off when the gate signal SGH is at a low level. The transistor TrL is turned on when the gate signal SGL supplied to the gate electrode is at a high level, and turned off when the gate signal SGL is at a low level. Therefore, an amplified signal Az obtained by amplifying the modulated signal Ms is output to a node Nd that electrically connects the source electrode of the transistor TrH and the drain electrode of the transistor TrL.

[0069] The smoothing circuit 42 is an LPF, i.e., a low pass filter, and smoothes the amplified signal Az to generate the driving signal Com-N[q]. The smoothing circuit 42 includes an inductor L0 and a capacitor C0. One end of the inductor L0 is electrically connected to the node Nd, and the other end is electrically connected to the output terminal Tn-out. One end of the capacitor C0 is electrically connected to the output terminal Tn-out, and the other end is electrically connected to a power supply line set to a ground potential. The driving signal Com-N[q] obtained by smoothing the amplified signal Az is output from the output terminal Tn-out.

[0070] The pull-up circuit 43 feeds back to the terminal Tn1 a signal SN1 obtained by pulling up the drive signal Com-N[q] output to the output terminal Tn-out. The pull-up circuit 43 includes a resistor R1 having one end electrically connected to the output terminal Tn-out and the other end electrically connected to the terminal Tn1, and a resistor R2 having one end electrically connected to the terminal Tn1 and the other end electrically connected to a power supply line set to the power supply potential VHV.

[0071] The filter circuit 44 is a BPF, i.e., a band pass filter, and feeds back to the terminal Tn2 a signal SN2 obtained by cutting DC components from frequency components in a predetermined band in the drive signal Com-N[q]. The filter circuit 44 includes a resistor R3, a capacitor C1 having one end electrically connected to the output terminal Tn-out and the other end electrically connected to one end of the resistor R3, a resistor R4 having one end electrically connected to one end of the resistor R3 and the other end electrically connected to a power supply line set to a ground potential, a capacitor C2 having one end electrically connected to the other end of the resistor R3 and the other end electrically connected to a power supply line set to a ground potential, and a capacitor C3 having one end electrically connected to the other end of the resistor R3 and the other end electrically connected to the terminal Tn2.

[0072] Among these, the capacitor C1 and the resistor R4 function as an HPF that passes high-frequency components of the drive signal Com-N[q] that are equal to or higher than the cutoff frequency, i.e., a high pass filter. The resistor R3 and the capacitor C2 function as an LPF that passes low-frequency components of the drive signal Com-N[q] that are equal to or lower than the cutoff frequency, i.e., a low pass filter. In this embodiment, the cutoff frequency of the HPF is set lower than the cutoff frequency of the LPF in the filter circuit 44. Therefore, the filter circuit 44 passes frequency components of a predetermined band that are equal to or higher than the cutoff frequency of the HPF and equal to or lower than the cutoff frequency of the LPF in the drive signal Com-N[q]. In addition, since the filter circuit 44 includes the capacitor C3, the filter circuit 44 feeds back to the terminal Tn2 a signal that has been cut of DC components from the signal of the frequency components of the predetermined band that have passed through the HPF and LPF in the drive signal Com-N[q].

[0073] In this way, the drive signal generation circuit GR-N[q] smoothes the amplified signal Az at the node Nd using the smoothing circuit 42 to generate the drive signal Com-N[q].

[0074] As described above, the driving signal Com-N[q] is a large-amplitude signal. Therefore, the inductor L0 and the capacitor C0 constituting the smoothing circuit 42 that outputs the driving signal Com-N[q] generate large amounts of heat. In this embodiment, it is assumed that the amount of heat generated by the inductor L0 is greater than the amount of heat generated by the capacitor C0. In addition, the amplified signal Az, which is the unsmoothed version of the drive signal Com-N[q], is also a large-amplitude signal, which increases the amount of heat generated by the transistors TrH and TrL constituting the amplifier circuit 41 that outputs the amplified signal Az.

[0075] <<4. Circuit Board Case>> Hereinafter, an overview of the substrate case 8 and the substrate accommodated in the substrate case 8 will be described with reference to FIGS.

[0076] <<4.1. Circuit board case and duct configuration>> FIG. 8 is an exploded perspective view showing an example of the configuration of the substrate case 8. As shown in FIG.

[0077] 8, the substrate case 8 includes a plurality of plate-shaped members that form the wall surfaces of the substrate case 8. Specifically, in the present embodiment, as an example, it is assumed that the wall surfaces of the substrate case 8 are formed of a plate-shaped member 811, a plate-shaped member 812, a plate-shaped member 813, a plate-shaped member 814, a plate-shaped member 815, a plate-shaped member 816, a plate-shaped member 817, a plate-shaped member 818, a plate-shaped member 819, and a plate-shaped member 820. In the following, the space inside the substrate case 8 is referred to as an internal space 80s.

[0078] The plate-like member 811 is a flat member having the Z1 direction as a normal direction, and constitutes a wall surface of the substrate case 8 at the end of the substrate case 8 in the Z2 direction. The plate-shaped member 812 is a flat member with the Y1 direction as the normal direction. The plate-shaped member 812 constitutes a wall surface of the substrate case 8 at the end in the Y2 direction of the substrate case 8. The plate-shaped member 812 is connected to the plate-shaped member 811 at the end in the Y2 direction of the substrate case 8. The plate-shaped member 813 is a flat member whose normal direction is the X1 direction. The plate-shaped member 813 constitutes a wall surface of the substrate case 8 at an end portion in the X2 direction of the substrate case 8. The plate-shaped member 813 is connected to the plate-shaped member 811 at an end portion in the X2 direction of the plate-shaped member 811, and is connected to the plate-shaped member 812 at an end portion in the X2 direction of the plate-shaped member 812. The plate-shaped member 814 is a flat member with the X2 direction as the normal direction. The plate-shaped member 814 constitutes a wall surface of the substrate case 8 at the end portion in the X1 direction of the substrate case 8. The plate-shaped member 814 is connected to the plate-shaped member 811 at the end portion in the X1 direction of the substrate case 811.

[0079] The plate-like member 815 is a flat member with the Y1 direction as its normal direction, and constitutes a wall surface of the substrate case 8. The plate-like member 815 is connected to the plate-like member 811, and is connected to the plate-like member 814 at an end of the plate-like member 814 in the Y2 direction. Plate-shaped member 816 is a flat member whose normal direction is the X2 direction, and constitutes a wall surface of substrate case 8. Plate-shaped member 816 is connected to plate-shaped member 811, connected to plate-shaped member 812 at an end of plate-shaped member 812 in the X1 direction, and connected to plate-shaped member 815 at an end of plate-shaped member 815 in the X2 direction. The plate-like member 817 is a flat member with the Y1 direction as its normal direction, and constitutes a wall surface of the substrate case 8. The plate-like member 817 is connected to the plate-like member 815 at an end of the plate-like member 815 in the X2 direction.

[0080] The plate-shaped member 818 is a flat member with the Z2 direction as its normal direction. The plate-shaped member 818 constitutes a wall surface of the board case 8 at an end in the Z1 direction of the board case 8. The plate-shaped member 818 is connected to the plate-shaped member 813 at an end in the Z1 direction of the board case 8, connected to the plate-shaped member 814 at an end in the Z1 direction of the board case 814, connected to the plate-shaped member 815 at an end in the Z1 direction of the board case 815, and connected to the plate-shaped member 817 at an end in the Z1 direction of the board case 817. Plate-shaped member 819 is a flat member whose normal direction is the Z2 direction, and constitutes a wall surface of substrate case 8. Plate-shaped member 819 is connected to plate-shaped member 812 at an end of plate-shaped member 812 in the Z1 direction, connected to plate-shaped member 816 at an end of plate-shaped member 816 in the Z1 direction, and connected to plate-shaped member 817 at an end of plate-shaped member 817 in the Z2 direction. The plate-shaped member 820 is a flat member with the Y2 direction as its normal direction. The plate-shaped member 820 constitutes a wall surface of the substrate case 8 at an end in the Y1 direction of the substrate case 8. The plate-shaped member 820 is connected to the plate-shaped member 811 at an end in the Y1 direction of the plate-shaped member 811, connected to the plate-shaped member 813 at an end in the Y1 direction of the plate-shaped member 813, connected to the plate-shaped member 814 at an end in the Y1 direction of the plate-shaped member 814, and connected to the plate-shaped member 818 at an end in the Y1 direction of the plate-shaped member 818.

[0081] In this embodiment, it is assumed that each of the multiple plate-shaped members constituting the wall surface of the substrate case 8 is formed of a metal material. However, the present invention is not limited to this embodiment. Of the multiple plate-shaped members constituting the wall surface of the substrate case 8, at least the plate-shaped member 817 and the plate-shaped member 819 may be formed of a metal material. That is, of the multiple plate-shaped members constituting the wall surface of the substrate case 8, a part or all of two or more plate-shaped members excluding the plate-shaped member 817 and the plate-shaped member 819 may be formed of a material other than a metal, such as a resin material. For example, of the multiple plate-shaped members constituting the wall surface of the substrate case 8, two or more plate-shaped members excluding the plate-shaped member 817 and the plate-shaped member 819 may be formed of a material other than a metal, such as a resin material.

[0082] As shown in FIG. 8, an intake fan 951 for supplying air to the inside of the board case 8 is provided in a portion of the plate member 814 located near the end in the Z1 direction, more specifically, in a portion of the plate member 814 located in the Z1 direction from the plate members 812 and 816. An intake fan 952 for supplying air to the inside of the board case 8 is provided in a portion of the plate member 816 located near the end in the Z1 direction, more specifically, in a portion of the plate member 816 closer to the end in the Z1 direction connected to the plate member 819 than the end in the Z2 direction connected to the plate member 811. An exhaust port 961 for discharging air from the inside of the board case 8 is provided in a portion of the plate member 813 located in the X2 direction as viewed from the intake fan 951. An exhaust port 962 for discharging air from the inside of the board case 8 is provided in a portion of the plate member 813 located in the X2 direction as viewed from the intake fan 952.

[0083] In this embodiment, air is an example of a "gas," intake fan 951 is an example of a "first fan," intake fan 952 is an example of a "second fan," plate-shaped member 817 is an example of a "first plate," and plate-shaped member 819 is an example of a "second plate."

[0084] 8, a duct 91 is provided on the outside of the board case 8 in an area located in the Z1 direction as viewed from the plate member 812 and in the Y2 direction as viewed from the plate member 818. The duct 91 is a conduit extending in the X1 direction and having wall surfaces formed of the plate members 817, 819, 911, and 912, and an internal space 91s that is the space inside the wall surfaces. The plate member 911 and the internal space 91s will be described later with reference to FIG. 11 or FIG. 14.

[0085] The duct 91 guides air, which is supplied from an air intake port 910 provided at the end of the duct 91 in the X2 direction, in the X1 direction.

[0086] 2, this embodiment assumes that the board case 8 is provided near the end in the X2 direction of the internal space of the housing 100 of the inkjet printer 1. Specifically, this embodiment assumes, as an example, that a plate-like member 813 constituting the end in the X2 direction of the board case 8 is provided so as to come into contact with a wall surface constituting the end in the X2 direction of the housing 100. This embodiment also assumes, as an example, that an air intake is provided in an area of ​​the housing 100 that is positioned in the X2 direction as viewed from the air intake 910. Therefore, the duct 91 can take in air from outside the inkjet printer 1 from the air intake 910, via the air intake provided in the housing 100.

[0087] In this embodiment, the duct 91 is an example of a "first duct", the intake port 910 is an example of an "opening", and the X1 direction is an example of a "first direction".

[0088] As shown in FIG. 8, a duct 92 is provided on the outside of the board case 8 in a region located in the X1 direction as viewed from the board case 8. The duct 92 is a conduit extending in the Y1 direction, having a wall surface formed of a plurality of plate-shaped members including a plate-shaped member 814, a plate-shaped member 921, a plate-shaped member 922, a plate-shaped member 923, and a plate-shaped member 924, and an internal space 92s which is a space inside the wall surface. The internal space 92s of the duct 92 communicates with the internal space 91s of the duct 91 at a connection port 92k which is an end of the duct 91 in the X1 direction. As described above, an intake fan 951 is provided in a portion of the duct 92 located near the end in the Y1 direction, and in a portion of the plate-shaped member 814 which constitutes the wall surface of the duct 92. The plate-shaped member 923, the plate-shaped member 924, the internal space 92s, and the connection port 92k will be described later with reference to FIG. 11.

[0089] The duct 92 guides the air supplied from the duct 91 through the connection port 92k in the Y1 direction. After that, the air guided in the Y1 direction by the duct 92 is supplied to the internal space 80s of the substrate case 8 by the intake fan 951. Specifically, the intake fan 951 blows the air supplied from the duct 92 in the X2 direction in the internal space 80s of the substrate case 8. Then, a part of the air supplied to the internal space 80s by the intake fan 951 is exhausted to the outside of the substrate case 8 through the exhaust port 961. That is, in this embodiment, an air flow from the intake fan 951 to the exhaust port 961 occurs in the internal space 80s. Hereinafter, the air flow from the intake fan 951 to the exhaust port 961 in the internal space 80s may be referred to as a gas flow path RT1.

[0090] In this embodiment, as an example, it is assumed that the exhaust port is provided in an area of ​​the housing 100 that is located in the X2 direction as viewed from the exhaust port 961. Therefore, the air flowing through the gas flow path RT1 is exhausted to the outside of the inkjet printer 1 via the exhaust port 961 and the exhaust port provided in the housing 100.

[0091] Thus, according to this embodiment, air supplied from the intake port 910 passes through the duct 91 extending in the X1 direction and the duct 92 extending in the Y1 direction, and is introduced into the internal space 80s of the substrate case 8 by the intake fan 951. Therefore, according to this embodiment, the possibility of foreign matter in the air, such as dust and paper powder, entering the internal space 80s can be reduced compared to a case in which the ducts 91 and 92 extend in the same direction. Thus, according to this embodiment, the possibility of the substrate housed inside the substrate case 8 being damaged due to the adhesion of foreign matter to the substrate housed inside the substrate case 8 can be reduced compared to a case in which the ducts 91 and 92 extend in the same direction.

[0092] Furthermore, according to this embodiment, air from outside the housing 100 of the inkjet printer 1 is supplied to the intake port 910. Therefore, according to this embodiment, it is possible to reduce the possibility that the mist of ink floating inside the housing 100 will infiltrate into the internal space 80s via the ducts 91 and 92, compared to an embodiment in which air inside the housing 100 of the inkjet printer 1 is supplied to the intake port 910. As a result, according to this embodiment, it is possible to reduce the possibility that the board housed inside the substrate case 8 will be damaged due to the mist adhering to the board housed inside the substrate case 8, compared to an embodiment in which air inside the housing 100 of the inkjet printer 1 is supplied to the intake port 910.

[0093] In this embodiment, the duct 92 is an example of a "second duct", and the Y1 direction is an example of a "second direction".

[0094] As shown in FIG. 8, the duct 93 is provided on the outside of the board case 8 in a region located in the X1 direction as viewed from the plate member 812 and in the Y2 direction as viewed from the plate member 814. The duct 93 is a conduit extending in the Z2 direction, having a wall surface formed of a plurality of plate members including the plate member 815, the plate member 816, the plate member 931, the plate member 911, and the plate member 912, and an internal space 93s which is a space inside the wall surface. The internal space 93s of the duct 93 communicates with the internal space 91s of the duct 91 at a connection port 93k located at the end of the duct 91 in the Z2 direction. As described above, the intake fan 952 is provided in a portion of the duct 93 located near the end in the Z2 direction, and in a portion of the plate member 816 which constitutes the wall surface of the duct 93. The plate-like member 931 and the internal space 93s will be described later with reference to FIG.

[0095] The duct 93 guides the air supplied from the duct 91 through the connection port 93k in the Z2 direction. After that, the air guided in the Z2 direction by the duct 93 is supplied to the internal space 80s of the board case 8 by the intake fan 952. Specifically, the intake fan 952 blows the air supplied from the duct 93 in the X2 direction in the internal space 80s of the board case 8. Then, a part of the air supplied to the internal space 80s by the intake fan 952 is exhausted to the outside of the board case 8 through the exhaust port 962. That is, in this embodiment, an air flow from the intake fan 952 to the exhaust port 962 occurs in the internal space 80s. Hereinafter, the air flow from the intake fan 952 to the exhaust port 962 in the internal space 80s may be referred to as a gas flow path RT2.

[0096] In this embodiment, as an example, it is assumed that the exhaust port is provided in an area of ​​the housing 100 that is located in the X2 direction as viewed from the exhaust port 962. Therefore, the air flowing through the gas flow path RT2 is exhausted to the outside of the inkjet printer 1 via the exhaust port 962 and the exhaust port provided in the housing 100.

[0097] Thus, according to this embodiment, air supplied from the intake port 910 passes through the duct 91 extending in the X1 direction and the duct 93 extending in the Z2 direction, and is introduced into the internal space 80s of the substrate case 8 by the intake fan 952. Therefore, according to this embodiment, the possibility of foreign matter in the air, such as dust and paper powder, entering the internal space 80s can be reduced compared to a case in which the duct 91 and the duct 93 extend in the same direction. Thus, according to this embodiment, the possibility of the substrate housed inside the substrate case 8 being damaged due to the adhesion of foreign matter to the substrate housed inside the substrate case 8 can be reduced compared to a case in which the duct 91 and the duct 93 extend in the same direction.

[0098] In this embodiment, the duct 93 is an example of a "third duct", and the Z2 direction is an example of a "third direction".

[0099] <<4.2. Boards housed in the board case>> The board housed in the board case 8 will be described below with reference to FIGS.

[0100] In this embodiment, it is assumed that a power supply circuit board 600 and a drive circuit board 400 are housed in the board case 8. Here, the power supply circuit board 600 is a board on which various electronic components constituting the power supply module 6 are arranged. Also, the drive circuit board 400 is a board on which various electronic components constituting the drive signal generating module 4 are arranged. Note that, in this embodiment, the various electronic components constituting the control module 2 may be arranged on the drive circuit board 400, the power supply circuit board 600, or a board different from the drive circuit board 400 and the power supply circuit board 600.

[0101] In this embodiment, the drive circuit board 400 is an example of a "first board," and the power supply circuit board 600 is an example of a "second board."

[0102] FIG. 9 is a perspective view showing the state in which the power supply circuit board 600 is accommodated in the board case 8. As shown in FIG.

[0103] 9, the power supply circuit board 600 is placed on the surface facing the Y1 direction out of two surfaces of the plate-shaped member 812. The power supply circuit board 600 is placed so that the normal direction of the surface on which the various electronic components constituting the power supply module 6 are arranged is the Y1 direction.

[0104] For this reason, in this embodiment, the gas flow path RT2 is located on the surface on which the various electronic components are arranged of the power supply circuit board 600. As a result, according to this embodiment, it is possible to cool the various electronic components arranged on the power supply circuit board 600 by the air flowing through the gas flow path RT2.

[0105] FIG. 10 is a perspective view showing a state in which the drive circuit board 400 is housed in addition to the power supply circuit board 600 in the board case 8. As shown in FIG.

[0106] 10, the drive circuit board 400 is installed on one of the two surfaces of the plate-shaped member 815 facing the Y1 direction, and on one of the two surfaces of the plate-shaped member 817 facing the Y1 direction. The drive circuit board 400 is installed so that the normal direction of the surface on which the various electronic components constituting the drive signal generation module 4 are arranged is the Y1 direction.

[0107] For this reason, in this embodiment, the gas flow path RT1 is located on the surface on which various electronic components are arranged of the drive circuit board 400. As a result, according to this embodiment, it is possible to cool the various electronic components arranged on the drive circuit board 400 by air flowing through the gas flow path RT1.

[0108] In the following, the configuration including the board case 8, the power supply circuit board 600 housed in the board case 8, the drive circuit board 400 housed in the board case 8, the duct 91, the duct 92, the duct 93, the intake fan 951, and the intake fan 952 as shown in FIG. 10 may be referred to as the "board unit."

[0109] FIG. 11 is a cross-sectional view of the board unit including the board case 8, taken along a plane passing through the line II-ii shown in FIG. 10 and having the Z1 direction as its normal direction.

[0110] As shown in FIG. 11, as described above, the duct 91 comprises a plate-shaped member 817 that forms the wall surface on the Y1 side of the duct 91, a plate-shaped member 911 that forms the wall surface on the Y2 side of the duct 91, and an internal space 91s that is the space between the plate-shaped member 817 and the plate-shaped member 911, and extends in the X1 direction to connect an air intake port 910 through which air is supplied from outside the housing 100 and a connection port 92k that connects to the internal space 92s of the duct 92. As described above, the duct 92 includes a plate-like member 924 that forms the X1-side wall surface of the duct 92, a plate-like member 814 that forms the X2-side wall surface of the duct 92, a plate-like member 922 that forms the Y1-side wall surface of the duct 92, a plate-like member 923 that forms the Y2-side wall surface of the duct 92, and an internal space 92s that is the space inside these multiple plate-like members, and extends in the Y1 direction to connect the connection port 92k and the intake fan 951 provided on the plate-like member 814.

[0111] Hereinafter, of the two faces of the plate-like member 817, the face facing the Y1 direction will be referred to as face 8171, and the face facing the Y2 direction will be referred to as face 8172. The face 8171 faces the internal space 80s. The face 8172 faces the internal space 91s. The drive circuit board 400 is placed on the face 8171.

[0112] In this embodiment, surface 8171 is an example of a "first surface," and surface 8172 is an example of a "second surface."

[0113] In addition, of the two faces of the drive circuit board 400, the face facing the Y1 direction is referred to as face 401, and the face facing the Y2 direction is referred to as face 402. Of these, various electronic components constituting the drive signal generating module 4 are arranged on face 401. In addition, air flowing through the gas flow path RT1 from the intake fan 951 to the exhaust port 961 contacts face 401. Therefore, the various electronic components arranged on face 401 are cooled by the air flowing through the gas flow path RT1. In addition, face 402 is fixed to face 8171 via a heat dissipation member 831. Therefore, heat generated by the various electronic components formed on face 401 is dissipated to the air flowing through the internal space 91s via the heat dissipation member 831.

[0114] In this embodiment, surface 401 is an example of a "first substrate surface," and surface 402 is an example of a "second substrate surface."

[0115] FIG. 12 is a cross-sectional view of the board unit including the board case 8, taken along a plane passing through line III-iii shown in FIG. 10 and having the Z1 direction as its normal direction.

[0116] As shown in FIG. 12, as described above, duct 93 includes plate-like member 931 forming the X1-side wall surface of duct 93, plate-like member 816 forming the X2-side wall surface of duct 93, plate-like member 815 forming the Y1-side wall surface of duct 93, plate-like member 911 forming the Y2-side wall surface of duct 93, and internal space 93s which is the space inside these multiple plate-like members, and extends in the Z2 direction so as to connect connection port 93k and intake fan 952 provided on plate-like member 816.

[0117] 12, of the two surfaces of the plate-shaped member 815, the drive circuit board 400 is placed on the surface facing the Y1 direction. Moreover, of the two surfaces of the plate-shaped member 812, the power supply circuit board 600 is placed on the surface facing the Y1 direction. Specifically, the power supply circuit board 600 is fixed to the plate-shaped member 812 via a heat dissipation member 832.

[0118] Of the power supply circuit board 600, the surface facing the Y1 direction comes into contact with the air flowing through the gas flow path RT2 from the intake fan 952 to the exhaust port 962. Therefore, various electronic components arranged on the power supply circuit board 600 are cooled by the air flowing through the gas flow path RT2. In addition, the drive circuit board 400 also comes into contact with the air flowing through the gas flow path RT2. Therefore, various electronic components arranged on the drive circuit board 400 are cooled by the air flowing through the gas flow path RT2.

[0119] A gap 451 is provided between the drive circuit board 400 and the plate-like member 813. For this reason, a part of the air supplied from the intake fan 952 and flowing through the gas flow path RT2 flows through the gap 451 into a region of the internal space 80s located in the Y1 direction from the drive circuit board 400, and is then discharged from the exhaust port 961. Also, a part of the air supplied from the intake fan 951 and flowing through the gas flow path RT1 flows through the gap 451 into a region of the internal space 80s located in the Y2 direction from the drive circuit board 400, and is then discharged from the exhaust port 962.

[0120] <<4.3. Layout of Electronic Components on the Drive Circuit Board>> Hereinafter, the electronic components disposed on the drive circuit board 400 will be described with reference to FIGS.

[0121] FIG. 13 is a plan view of the drive circuit board 400 when viewed from the Y1 direction toward the Y2 direction.

[0122] 13, on the surface 401 of the drive circuit board 400, in addition to Q drive signal generating circuits GR-A[1] to GR-A[Q] and Q drive signal generating circuits GR-B[1] to GR-B[Q], Q electrolytic capacitors 47[1] to 47[Q], Q electrolytic capacitors 48-A[1] to 48-A[Q], and Q electrolytic capacitors 48-B[1] to 48-B[Q] are provided. Here, the electrolytic capacitor 47[q] is an electronic component for supplying a power supply potential VHV to the drive signal generating unit GR[q] and the head unit HU[q]. Also, the electrolytic capacitor 48-A[q] is an electronic component for supplying a potential VBS to the drive signal generating circuit GR-A[q] and the head unit HU[q]. Moreover, the electrolytic capacitor 48-B[q] is an electronic component for supplying a potential VBS to the drive signal generating circuit GR-B[q] and the head unit HU[q]. In the following, the electrolytic capacitor 48-A[q] and the electrolytic capacitor 48-B[q] may be collectively referred to as the electrolytic capacitor 48-N[q]. In other words, the electrolytic capacitor 48-N[q] is an electronic component for supplying a potential VBS to the drive signal generating circuit GR-N[q] and the head unit HU[q].

[0123] In this embodiment, the drive signal generating circuit GR-N[q] is disposed between the electrolytic capacitor 47[q] and the plate-like member 818 in the Z-axis direction. In this embodiment, the electrolytic capacitor 47[q] is disposed between the electrolytic capacitor 48-N[q] and the drive signal generating circuit GR-N[q] in the Z-axis direction. In this embodiment, the Q electrolytic capacitors 47[1] to 47[Q] are disposed along the X1 direction, which is the extension direction of the gas flow path RT1. In this embodiment, the Q electrolytic capacitors 48-A[1] to 48-A[Q] and the Q electrolytic capacitors 48-B[1] to 48-B[Q] are disposed along the X1 direction, which is the extension direction of the gas flow path RT1.

[0124] Moreover, in this embodiment, the electrolytic capacitor 47[q] is disposed so that the intake fan 951 is located between the electrolytic capacitor 47[q] and the plate-shaped member 818 in the Z-axis direction. Moreover, in this embodiment, the electrolytic capacitor 47[q] is disposed so that the exhaust port 961 is located between the electrolytic capacitor 47[q] and the plate-shaped member 818 in the Z-axis direction. However, the present invention is not limited to this embodiment. Electrolytic capacitor 47[q] may be arranged such that at least a portion of intake fan 951 is located between electrolytic capacitor 47[q] and plate-like member 818 in the Z-axis direction. Electrolytic capacitor 47[q] may be arranged such that at least a portion of exhaust port 961 is located between electrolytic capacitor 47[q] and plate-like member 818 in the Z-axis direction.

[0125] In this embodiment, various electronic components constituting the drive signal generation circuit GR-N[q] are arranged on the surface 401 of the drive circuit board 400. Specifically, various electronic components including an integrated circuit 40, a transistor pair having a transistor TrH and a transistor TrL, a capacitor C0, and an inductor L0 are arranged on the surface 401 of the drive circuit board 400.

[0126] In this embodiment, it is assumed that the transistors TrH and TrL and the inductor L0 are provided between the intake fan 951 and the exhaust port 961 when the drive circuit board 400 is viewed in the Y2 direction. That is, in this embodiment, it is assumed that the transistors TrH and TrL and the inductor L0 are provided in a range in the Z-axis direction where the intake fan 951 is present and where the exhaust port 961 is present. However, the present invention is not limited to this embodiment. At least a part of the transistors TrH and TrL and the inductor L0 may be provided in a range in the Z-axis direction different from the range in which the intake fan 951 is present and different from the range in which the exhaust port 961 is present.

[0127] Figure 14 is a cross-sectional view of a board unit including a board case 8 housing a drive circuit board 400, cut along a plane passing through line IV-iv shown in Figure 13, with the X1 direction being the normal direction.

[0128] 14, as described above, the duct 91 includes a plate member 817 constituting the wall surface on the Y1 side of the duct 91, a plate member 911 constituting the wall surface on the Y2 side of the duct 91, a plate member 912 constituting the wall surface on the Z1 side of the duct 91, a plate member 819 constituting the wall surface on the Z2 side of the duct 91, and an internal space 91s which is a space inside these multiple plate members. In the following, of the two faces of the plate member 819, the face facing the Z2 direction is referred to as face 8191, and the face facing the Z1 direction is referred to as face 8192. The face 8191 faces the internal space 80s. The face 8192 faces the internal space 91s.

[0129] In this embodiment, surface 8191 is an example of a "third surface," and surface 8192 is an example of a "fourth surface."

[0130] As shown in FIG. 14, the height in the Y1 direction of the integrated circuit 40 provided on the surface 401 is referred to as height H1, the height in the Y1 direction of the transistor TrH and the transistor TrL provided on the surface 401 is referred to as height H2, the height in the Y1 direction of the capacitor C0 provided on the surface 401 is referred to as height H3, the height in the Y1 direction of the inductor L0 provided on the surface 401 is referred to as height H4, the height in the Y1 direction of the electrolytic capacitor 47[q] provided on the surface 401 is referred to as height H5, and the height in the Y1 direction of the electrolytic capacitor 48-N[q] provided on the surface 401 is referred to as height H6.

[0131] In the present embodiment, as an example, it is assumed that the heights H1, H2, H3, and H4 are different from one another. Among these, the height H4 of the inductor L0 is higher than the height H2 of the transistors TrH and TrL. In this embodiment, the height H5 of the electrolytic capacitor 47[q] is greater than the height H6 of the electrolytic capacitor 48-N[q]. However, the present invention is not limited to this embodiment. The height H5 of the electrolytic capacitor 47[q] may be less than the height H6 of the electrolytic capacitor 48-N[q].

[0132] In this embodiment, the height H5 of the electrolytic capacitor 47[q] is higher than the height H1 of the integrated circuit 40, higher than the height H2 of the transistors TrH and TrL, higher than the height H3 of the capacitor C0, and higher than the height H4 of the inductor L0. In this embodiment, the height H6 of the electrolytic capacitor 48-N[q] is higher than the height H1 of the integrated circuit 40, higher than the height H2 of the transistors TrH and TrL, higher than the height H3 of the capacitor C0, and higher than the height H4 of the inductor L0.

[0133] In this embodiment, the transistor TrH or the transistor TrL is an example of a "first electronic component," the inductor L0 is an example of a "second electronic component," and the electrolytic capacitor 47[q] or the electrolytic capacitor 48-N[q] is an example of a "third electronic component." In this embodiment, the height H2 of the transistor TrH and the transistor TrL is an example of a "first height," the height H4 of the inductor L0 is an example of a "second height," and the height H5 of the electrolytic capacitor 47[q] or the height H6 of the electrolytic capacitor 48-N[q] is an example of a "third height."

[0134] Thus, according to this embodiment, the electrolytic capacitor 47[q] and / or the electrolytic capacitor 48-N[q] can prevent the air moving from the intake fan 951 toward the exhaust port 961 from moving in the Z2 direction beyond the electrolytic capacitor 47[q] and / or the electrolytic capacitor 48-N[q]. That is, the electrolytic capacitor 47[q] and / or the electrolytic capacitor 48-N[q] form the side wall of the gas flow path RT1. That is, in this embodiment, the gas flow path RT1 is provided so as to contact various electronic components on the drive circuit board 400 in the Z-axis direction at least over the range from the plate-shaped member 818 to the electrolytic capacitor 47[q]. As a result, according to this embodiment, compared to an embodiment in which the electrolytic capacitor 47[q] and the electrolytic capacitor 48-N[q] are not provided on the surface 401 of the drive circuit board 400, it is possible to strengthen the air flow in the gas flow path RT1, and it is possible to efficiently cool various electronic components that constitute the drive signal generation module 4, such as the transistors TrH and TrL, the capacitor C0, and the inductor L0.

[0135] In this embodiment, as an example, it is assumed that a transistor pair consisting of a transistor TrH and a transistor TrL is disposed at a position closer to the center of the gas flow path RT1 in the Z-axis direction than the integrated circuit 40. Therefore, according to this embodiment, the transistor pair can be cooled by the gas flow path RT1 more efficiently than in a case where the transistor pair is disposed at a position farther from the center of the gas flow path RT1 than the integrated circuit 40. Furthermore, in this embodiment, the inductor L0 may be disposed at a position closer to the center of the gas flow path RT1 in the Z-axis direction than the integrated circuit 40. In this case, the inductor L0 can be cooled more efficiently by the gas flow path RT1 compared to an embodiment in which the inductor L0 is disposed at a position farther from the center of the gas flow path RT1 than the integrated circuit 40. In addition, in this embodiment, as an example, it is assumed that a capacitor C0 is disposed between a transistor pair consisting of a transistor TrH and a transistor TrL and an inductor L0. In this case, it is possible to prevent the transistor pair and the inductor L0 from becoming too hot, compared to an embodiment in which the transistor pair and the inductor L0 are disposed adjacent to each other.

[0136] Moreover, according to this embodiment, the gas flow path RT2 is provided so as to contact various electronic components on the power supply circuit board 600. As a result, according to this embodiment, the various electronic components constituting the power supply module 6 can be cooled more efficiently than in a case where the gas flow path RT2 is not provided in the internal space 80s.

[0137] Furthermore, according to this embodiment, heat generated by various electronic components on the drive circuit board 400 is dissipated to the air flowing through the gas flow path RT2 via the heat dissipation member 831, the plate-shaped member 817, and the plate-shaped member 819. Therefore, according to this embodiment, the various electronic components constituting the drive signal generating module 4 can be cooled more efficiently than in a mode in which the gas flow path RT2 is not provided in the internal space 80s.

[0138] According to the present embodiment, heat generated by various electronic components on the drive circuit board 400 is dissipated to the air flowing through the internal space 91s of the duct 91 via the heat dissipation member 831 and the plate-like member 817. In the present embodiment, the air flow in the duct 91 is generated by the intake fan 951 and the intake fan 952. Therefore, according to the present embodiment, the air flow in the duct 91 can be strengthened compared to a case in which only one of the intake fan 951 and the intake fan 952 is provided to the board case 8. Therefore, according to the present embodiment, the various electronic components constituting the drive signal generating module 4 can be cooled more efficiently compared to a case in which only one of the intake fan 951 and the intake fan 952 is provided to the board case 8.

[0139] <<5. Conclusion of the embodiment>> As described above, the inkjet printer 1 according to this embodiment comprises a board case 8 in which a drive circuit board 400 is housed, a duct 91 extending in the X1 direction to which air is supplied via an intake port 910, a duct 92 that communicates with the duct 91 and extends in the Y1 direction intersecting the X1 direction, and an intake fan 951 that supplies air from the duct 92 to the internal space 80s of the board case 8, and is characterized in that the direction in which the intake fan 951 supplies air is different from the X1 direction and the Y1 direction.

[0140] Thus, according to this embodiment, air supplied from the intake port 910 is introduced into the internal space 80s via a curved introduction path including the duct 91 extending in the X1 direction and the duct 92 extending in the Y1 direction. Therefore, according to this embodiment, it is possible to reduce the possibility that foreign matter mixed in the air will enter the internal space 80s, compared to a mode in which air is introduced into the internal space 80s via a linear introduction path and a mode in which air is introduced into the internal space 80s directly from the intake port 910.

[0141] Furthermore, the inkjet printer 1 according to this embodiment is characterized in that the direction in which the intake fan 951 supplies air is the X2 direction, which is opposite to the X1 direction.

[0142] For this reason, according to this embodiment, when the inkjet printer 1 is viewed from a direction intersecting the X1 direction and the X2 direction, the duct 91 can be provided so that the duct 91 and the board case 8 overlap. Therefore, according to this embodiment, the drive circuit board 400 housed in the board case 8 can be cooled by the air passing through the duct 91.

[0143] Furthermore, the inkjet printer 1 according to this embodiment is characterized in that air is supplied to the duct 91 from outside the inkjet printer 1 via an air intake 910.

[0144] Therefore, according to this embodiment, compared to a configuration in which air inside the inkjet printer 1 is supplied to the duct 91, it is possible to reduce the possibility of ink mist floating inside the inkjet printer 1 entering the internal space 80s of the board case 8.

[0145] Furthermore, the inkjet printer 1 according to this embodiment is characterized in that it is provided with a duct 93 that communicates with the duct 91 and extends in the Z2 direction that intersects the X1 direction and the Y1 direction, and an intake fan 952 that supplies air from the duct 93 to the internal space 80s of the substrate case 8.

[0146] Therefore, according to this embodiment, it is possible to cool the drive circuit board 400 more efficiently than in a mode in which air is introduced into the internal space 80s by only the intake fan 951.

[0147] Furthermore, in the inkjet printer 1 according to this embodiment, the board case 8 is provided with a metal plate-like member 817 having a surface 8171 on which the drive circuit board 400 is mounted and a surface 8172 opposite to surface 8171, and surface 8172 forms part of the wall surface of the duct 91.

[0148] Therefore, according to this embodiment, the drive circuit board 400 can be cooled by the air flowing through the internal space 91s of the duct 91 via the plate-like member 817.

[0149] Furthermore, in the inkjet printer 1 according to this embodiment, the base plate case 8 is provided with a metal plate member 819 connected to the plate member 817, and the plate member 819 has a surface 8191 facing the inside of the base plate case 8 and a surface 8192 opposite to surface 8191, and surface 8192 forms part of the wall surface of the duct 91.

[0150] Therefore, according to this embodiment, the drive circuit board 400 can be cooled by the air flowing through the internal space 91s of the duct 91 via the plate members 819 and 817.

[0151] The inkjet printer 1 according to this embodiment is characterized in that it comprises a drive circuit board 400 having a surface 401 and a surface 402 opposite to surface 401, a transistor TrH provided on surface 401 and having a height H2 in the normal direction to surface 401, an inductor L0 provided on surface 401 and having a height H4 greater than height H2 in the normal direction to surface 401, a metal plate-like member 817 having a surface 8171 on which surface 402 of the integrated circuit 40 is provided and a surface 8172 opposite surface 8171, a substrate case 8 that houses the drive circuit board 400, and an intake fan 951 that supplies air from the outside of the substrate case 8 to the inside and generates an airflow on the surfaces of the transistor TrH and the inductor L0, and surface 8172 comes into contact with the air outside the substrate case 8.

[0152] Thus, according to this embodiment, heat generated by the transistor TrH and inductor L0 provided on the drive circuit board 400 is dissipated to the air outside the board case 8 via the plate-like member 817 on which the drive circuit board 400 is provided. Therefore, according to this embodiment, it is possible to simplify the configuration for cooling the electronic components provided on the drive circuit board 400, compared to an embodiment in which a heat sink having a protrusion corresponding to the height of the transistor TrH and a protrusion corresponding to the height of the inductor L0 is provided. Furthermore, according to this embodiment, the transistor TrH and inductor L0 provided on the drive circuit board 400 are cooled by utilizing the airflow generated by the intake fan 951. Therefore, according to this embodiment, it is possible to simplify the configuration for cooling the electronic components provided on the drive circuit board 400, compared to an embodiment in which a heat sink having a protrusion corresponding to the height of the transistor TrH and a protrusion corresponding to the height of the inductor L0 is provided. Furthermore, according to this embodiment, the transistor TrH and inductor L0 provided on the drive circuit board 400 are cooled by both heat dissipation via the plate-like member 817 and the airflow generated by the intake fan 951. Therefore, according to this embodiment, it is possible to prevent the transistor TrH and inductor L0 provided on the drive circuit board 400 from becoming too hot, compared to an embodiment in which the transistor TrH and inductor L0 provided on the drive circuit board 400 are cooled only by a heat sink.

[0153] Furthermore, the inkjet printer 1 according to this embodiment is characterized in that a heat dissipation member 831 is provided between the surface 402 and the surface 8171.

[0154] Therefore, according to this embodiment, the heat dissipation efficiency is higher when dissipating heat from the drive circuit board 400 to the outside of the board case 8 via the plate-shaped member 817, compared to a configuration in which the heat dissipation member 831 is not provided between the surface 402 and the surface 8171.

[0155] Furthermore, in the inkjet printer 1 according to this embodiment, the board case 8 is characterized by comprising a metal plate member 819 connected to the plate member 817, and an intake fan 952 that supplies air from the outside to the inside of the board case 8 and generates an airflow on the surface of the plate member 819.

[0156] Therefore, according to this embodiment, the intake fan 952 generates an airflow on the surface of the plate-like member 819, thereby improving the heat dissipation efficiency when heat generated by electronic components on the drive circuit board 400 is dissipated via the plate-like members 817 and 819. Therefore, according to this embodiment, it is possible to cool the drive circuit board 400 more efficiently than in a mode in which air is introduced into the inside of the board case 8 by only the intake fan 951.

[0157] Furthermore, the inkjet printer 1 according to this embodiment comprises a head unit HU[q] that ejects ink in response to a drive signal Com-N[q], and a drive signal generation circuit GR-N[q] that generates the drive signal Com-N[q], and the drive signal generation circuit GR-N[q] comprises a transistor TrH and an inductor L0.

[0158] The inkjet printer 1 according to this embodiment is further characterized in that it includes Q electrolytic capacitors 47[1] to 47[Q] provided on the surface 401 and arranged along the X2 direction in which the intake fan 951 supplies air, each of the Q electrolytic capacitors 47[1] to 47[Q] having a height H5 that is higher than the height H4 in the normal direction to the surface 401, the Q electrolytic capacitors 47[1] to 47[Q] forming a side wall of a gas flow path RT1 through which air supplied from the intake fan 951 flows, and the transistor TrH and the inductor L0 being provided in the gas flow path RT1.

[0159] Thus, according to this embodiment, the side walls of the gas flow path RT1 are formed by the Q electrolytic capacitors 47[1]-47[Q], so that the airflow generated in the gas flow path RT1 can be strengthened compared to an embodiment in which the Q electrolytic capacitors 47[1]-47[Q] are not provided. Therefore, according to this embodiment, the transistor TrH and the inductor L0 can be cooled more efficiently by the air flowing through the gas flow path RT1 compared to an embodiment in which the Q electrolytic capacitors 47[1]-47[Q] are not provided.

[0160] The inkjet printer 1 according to this embodiment is characterized in that it includes a power supply circuit board 600 housed in a board case 8, and the intake fan 952 generates an air current on the surface of the power supply circuit board 600.

[0161] Therefore, according to this embodiment, the two boards, the drive circuit board 400 and the power supply circuit board 600, housed in the board case 8 can be cooled.

[0162] In the inkjet printer 1 according to the present embodiment, the substrate case 8 is provided with an exhaust port 961 for discharging air from the inside of the substrate case 8 to the outside, and the transistor TrH and the inductor L0 are provided between the intake fan 951 and the exhaust port 961 in a plan view of the surface 401, which is a feature.

[0163] Therefore, according to the present embodiment, the air flowing through the gas flow path RT1 from the intake fan 951 toward the exhaust port 961 can efficiently cool the transistor TrH and the inductor L0.

[0164] Further, in the inkjet printer 1 according to the present embodiment, it may be characterized in that the force with which the intake fan 951 supplies air to the inside of the substrate case 8 and the force with which the intake fan 952 supplies air to the inside of the substrate case 8 are substantially the same.

[0165] Therefore, according to the present embodiment, it is possible to reduce the types of parts of the inkjet printer 1 as compared with a mode in which the forces for supplying air by the intake fan 951 and the intake fan 952 are different, and the cost related to the manufacture of the inkjet printer 1 can be reduced. In the present embodiment, "substantially the same" is a concept that includes cases where, in addition to the case of complete coincidence, it can be regarded as the same when various errors such as manufacturing errors are taken into account. Specifically, in the present embodiment, "substantially the same" is a concept that includes cases where it can be regarded as the same when an error of about 5% is excluded.

[0166] <<B. Modification Example>> Each of the above embodiments can be variously modified. Specific modification modes are exemplified below. Two or more modes arbitrarily selected from the following examples can be appropriately combined within a range where they do not conflict with each other. In the modification examples exemplified below, for elements whose actions and functions are equivalent to those of the embodiment, the reference numerals referred to in the above description are used, and the detailed description of each is appropriately omitted.

[0167] <<Modification Example 1>> In the above embodiment, the case where the air outside the housing 100 is supplied to the internal space 80s of the substrate case 8 via the duct 91, the duct 92, and the duct 93 has been described as an example, but the present invention is not limited to such an embodiment. The air inside the housing 100 may be supplied to the internal space 80s of the substrate case 8.

[0168] In the above embodiment, the case where the air in the internal space 80s of the substrate case 8 is exhausted to the outside of the housing 100 through the exhaust port 961 and the exhaust port 962 has been described as an example, but the present invention is not limited to this aspect. The air in the internal space 80s of the substrate case 8 may be exhausted to the inside of the housing 100 through the exhaust port 961 and the exhaust port 962.

[0169] <<Variation 2>> In the above-described embodiment and modification 1, an example has been described in which ducts 91, duct 92, and duct 93 are provided outside the board case 8, but the present invention is not limited to this aspect. For example, the inkjet printer 1 may be configured without some or all of ducts 91, duct 92, and duct 93. Specifically, the inkjet printer 1 may be configured with ducts 91 and duct 92, but without duct 93. Alternatively, the inkjet printer 1 may be configured with ducts 91 and duct 93, but without duct 92. Alternatively, the inkjet printer 1 may be configured without ducts 91, duct 92, and duct 93.

[0170] FIG. 15 is an exploded perspective view showing an example of the configuration of a substrate case 8B according to this modified example.

[0171] As shown in FIG. 15, the substrate case 8B is configured in the same manner as the substrate case 8 according to the embodiment, except that the ducts 91, 92, and 93 are not provided around the substrate case 8B.

[0172] In this modified example, the board case 8B can also accommodate the drive circuit board 400 and the power supply circuit board 600. Specifically, the board case 8B can accommodate the power supply circuit board 600 on a plate-shaped member 812 included in the board case 8B, and the drive circuit board 400 can be arranged on plate-shaped members 817 and 815 included in the board case 8B.

[0173] FIG. 16 is a cross-sectional view of a board unit including the board case 8B shown in FIG. 15, taken along a plane having the X1 direction as a normal direction.

[0174] 16, also in the board case 8B, an intake fan 951 and an exhaust port 961 allow a gas flow path RT1 to be disposed on the surface 401 of the drive circuit board 400. Also in the board case 8B, an intake fan 952 and an exhaust port 962 allow a gas flow path RT2 to be disposed on the power supply circuit board 600. Therefore, also in the board case 8B, various electronic components formed on the drive circuit board 400 and various electronic components formed on the power supply circuit board 600 can be efficiently cooled.

[0175] <<Variation 3>> In the above-described embodiment and modified examples 1 and 2, an example has been described in which two intake fans, intake fan 951 and intake fan 952, and two exhaust ports, exhaust port 961 and exhaust port 962, are provided in board case 8 or board case 8B, but the present invention is not limited to such an example. Of the two intake fans, intake fan 951 and intake fan 952, it is sufficient that at least intake fan 951 is provided in board case 8 and board case 8B, and intake fan 952 may not be provided. Also, of the two exhaust ports, exhaust port 961 and exhaust port 962, it is sufficient that at least exhaust port 961 is provided in board case 8 and board case 8B, and exhaust port 962 may not be provided.

[0176] <<Variation 4>> In the above-described embodiment and modified examples 1 to 3, the inkjet printer 1 is a serial printer, but the present invention is not limited to this. The inkjet printer 1 may be a so-called line printer in which the (M×Q) nozzles N of the head module 3 are arranged to extend wider than the width of the recording paper PP. [Explanation of symbols]

[0177] 1...inkjet printer, 2...control module, 3...head module, 4...drive signal generating module, 6...power supply module, 7...transport module, 8...substrate case, 40...integrated circuit, 47[q]...electrolytic capacitor, 48-A[q]...electrolytic capacitor, 48-B[q]...electrolytic capacitor, TrH...transistor, TrL...transistor, 91...duct, 92...duct, 93...duct , 100...housing, 400...drive circuit board, 600...power supply circuit board, 811...plate-shaped member, 812...plate-shaped member, 813...plate-shaped member, 814...plate-shaped member, 815...plate-shaped member, 816...plate-shaped member, 817...plate-shaped member, 818...plate-shaped member, 819...plate-shaped member, 820...plate-shaped member, 951...intake fan, 952...intake fan, 961...exhaust port, 962...exhaust port, C0...capacitor, L0...inductor.

Claims

1. a substrate case in which the substrate is housed; a first duct extending in a first direction and to which gas is supplied via an opening; a second duct communicating with the first duct and extending in a second direction intersecting the first direction; a first fan that supplies gas from the second duct to an inside of the substrate case; Equipped with A direction in which the first fan supplies gas is different from the first direction and the second direction. A printing device comprising:

2. The direction in which the first fan supplies gas is opposite to the first direction.

2. The printing device according to claim 1 .

3. Gas is supplied to the first duct from outside the printing apparatus through the opening.

2. The printing device according to claim 1 .

4. a third duct communicating with the first duct and extending in a third direction intersecting the first direction and the second direction; a second fan that supplies gas from the third duct to an inside of the substrate case; Equipped with 2. The printing device according to claim 1 .

5. the board case includes a first plate made of metal and having a first surface on which the board is placed and a second surface opposite to the first surface; The second surface constitutes a part of a wall surface of the first duct.

2. The printing device according to claim 1 .

6. the circuit board case includes a second plate made of metal and connected to the first plate; the second plate has a third surface facing the inside of the board case and a fourth surface opposite to the third surface, The fourth surface constitutes a part of a wall surface of the first duct.

6. The printing device according to claim 5, wherein the printing device further comprises:

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