JP2012111116A - Printing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve safety by making it difficult for a user to touch a high temperature part of a radiator.SOLUTION: The printing device includes: a housing; a cover provided in the housing and capable of uncovering an inside space; a heating element provided in the housing; the radiator which is used for radiating heat generated by the heating element, and provided in the space so that at least a part of it is exposed; and a detecting section for detecting the temperature of the heating element. A plurality of pieces of abnormal state removal processing are predetermined for the case that a detection result obtained by the detecting section exceeds a predetermined temperature. If the detection result exceeds the predetermined temperature, one of the plurality of pieces of abnormal state removal processing is performed according to the level of the detection result.

Description

  The present invention relates to a printing apparatus.

  As an example of a printing apparatus, an ink jet printer that ejects ink by driving a drive element using a drive signal is known. Such a printer uses a heating element that generates heat during driving. For example, a drive signal generation circuit that generates a drive signal includes a current amplification circuit including a transistor pair, and these transistors generate heat when generating the drive signal. In addition, various motors are used in the printer, and the motor driver that drives these also generates heat similarly. In view of this, there has been proposed a heat sink that dissipates heat generated by a heat generator such as a transistor pair (see, for example, Patent Document 1).

JP 2008-197461 A

Due to space limitations, there is a possibility that the heat dissipator is placed where the user may touch. For example, a heat radiating body may be exposed in an internal space that is opened by opening a printer cover. In this case, if the heating element is abnormally heated, there is a problem that the user may touch the high-temperature radiator.
Therefore, an object of the present invention is to improve safety.

A main invention for achieving the above object is generated by a casing, a cover provided in the casing and capable of opening an internal space, a heating element provided in the casing, and the heating element. A heat dissipating body for dissipating heat, the heat dissipating body provided at least partially exposed in the internal space, and a detection unit for detecting the temperature of the heating unit, the detection result of the detection unit A plurality of abnormality processes are defined for a case where the temperature exceeds a predetermined temperature, and if the detection result exceeds the predetermined temperature, one of the plurality of abnormality processes depending on the magnitude of the detection result. The printing apparatus is characterized by executing the following.
Other features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

1 is a block diagram illustrating an overall configuration of a printer. 2A and 2B are external views of the printer 1. 3A and 3B are diagrams illustrating the internal configuration of the printer 1. 4 is a cross-sectional view showing a structure of a head 41. FIG. It is a figure for demonstrating the mode of heat dissipation. It is a flowchart for demonstrating the process at the time of printing in this embodiment. 7A and 7B are explanatory diagrams of the operation of the first abnormality process. It is a flowchart of a 1st abnormality process. 9A and 9B are explanatory diagrams of the operation of the modified example of the first abnormality process. It is a flowchart of a 2nd abnormality process. It is a simplified explanatory view of the carriage stop position in the second abnormality process. FIG. 10 is a simplified explanatory diagram of a carriage stop position in Modification 1 of the second abnormality process. FIG. 10 is a simplified explanatory diagram of a carriage stop position in Modification 2 of the second abnormality process. It is a flowchart of a 3rd abnormality process.

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

A casing, a cover provided in the casing and capable of opening an internal space, a heating element provided in the casing, and a radiator that dissipates heat generated by the heating element, A heat dissipating body that is at least partially exposed in the internal space, and a detecting unit that detects the temperature of the heat generating unit, wherein a plurality of abnormalities are detected when the detection result of the detecting unit exceeds a predetermined temperature A printing apparatus characterized in that, when a process is determined and the detection result exceeds the predetermined temperature, one of the plurality of abnormal processes is executed according to the magnitude of the detection result. It becomes clear.
According to such a printing apparatus, safety can be improved.

In this printing apparatus, it is preferable that at least one of the plurality of abnormality processes is to separate the heat generating body and the heat radiating body in conjunction with an operation of opening the cover.
According to such a printing apparatus, the temperature of the radiator can be lowered when the user may touch the radiator.

In this printing apparatus, the housing has a spare heat radiator different from the heat radiator, and in conjunction with the operation of opening the cover, the heating element and the heat radiator are separated from each other and It is desirable to bring the heating element into contact with the preliminary heat radiating body.
According to such a printing apparatus, it is possible to prevent an influence (failure or the like) due to heat generation by the preliminary heat radiator while lowering the temperature of the heat radiator.

In this printing apparatus, an opening provided in the housing and a carriage provided in the housing so as to be movable in a predetermined direction, the position from the opening is more than the heating element. A carriage provided on the front side, and at least one of the plurality of abnormality treatments stops the carriage at a position covering at least a part of the heating element when viewed from the opening side. It may be.
According to such a printing apparatus, it is possible to make it difficult to touch the hottest part of the heat radiating body, and to improve safety.

In this printing apparatus, an opening provided in the housing and a carriage provided in the housing so as to be movable in a predetermined direction, the position from the opening is more than the heating element. A carriage provided on the front side, and at least one of the plurality of abnormality treatments stops the carriage at a position covering at least a part of the opening as viewed from the opening. It may be.
According to such a printing apparatus, it is possible to make it difficult to touch the hottest part of the heat radiating body, and to improve safety.

In this printing apparatus, an opening provided in the housing and a carriage provided in the housing so as to be movable in a predetermined direction, the position from the opening is more than the heating element. A carriage provided on the front side, and at least one of the plurality of abnormality processes is configured such that at least a part of the carriage is positioned between the heating element and the opening. It may be to stop.
According to such a printing apparatus, it is possible to make it difficult to touch the hottest part of the heat radiating body, and to improve safety.

In this printing apparatus, at least one of the plurality of abnormality processes may be locked with the cover closed.
According to such a printing apparatus, it is possible to reliably prevent the user from touching the radiator.

  In the following embodiments, description will be made using an inkjet printer as a printing apparatus.

=== First Embodiment ===
≪Printer configuration≫
FIG. 1 is a block diagram illustrating the overall configuration of the printer 1. 2A and 2B are external views of the printer 1. 3A and 3B are diagrams illustrating an internal configuration of the printer 1 according to the present embodiment.

  The printer 1 is an ink jet printer that records (prints) characters and images by ejecting ink onto a medium such as paper, cloth, and film, and is communicably connected to a computer 110 that is an external device.

A printer driver is installed in the computer 110. The printer driver is a program for displaying a user interface on a display device (not shown) and converting image data output from an application program into print data. This printer driver is recorded on a recording medium (computer-readable recording medium) such as a flexible disk FD or a CD-ROM. Also, the printer driver can be downloaded to the computer 110 via the Internet. In addition, this program is comprised from the code | cord | chord for implement | achieving various functions.
The computer 110 outputs print data corresponding to the image to be printed to the printer 1 in order to cause the printer 1 to print an image.

The printer 1 includes a housing 10 and a cover 11 as shown in FIGS. 2A and 2B.
The housing 10 is for housing each unit (described later) of the printer 1 inside. As shown in FIG. 2B, the housing 10 is provided with an opening 10a. The opening 10a is closed by the cover 11 when the cover 11 is closed (FIG. 2A), and the opening 10a appears when the cover 11 is opened (FIG. 2B).
The cover 11 is provided in the housing 10 so that it can be opened and closed. By opening the cover 11 (in an open state), the internal space of the printer 1 can be opened through the opening 10a. .

Hereinafter, details of each unit provided in the printer 1 will be described.
The printer 1 includes a transport unit 20, a carriage unit 30, a head unit 40, a detector group 50, a controller 60, and a heat dissipation unit 80. The controller 60 controls each unit based on print data received from the computer 110 that is an external device, and prints an image on a medium. The situation in the printer 1 is monitored by the detector group 50, and the detector group 50 outputs the detection result to the controller 60. The controller 60 controls each unit based on the detection result output from the detector group 50.

<Transport unit 20>
The transport unit 20 is for transporting a medium (for example, paper S) in a predetermined direction (hereinafter referred to as a transport direction). Here, the conveyance direction is a direction that intersects a direction in which a carriage 31 described later moves (hereinafter referred to as a movement direction). The transport unit 20 includes a paper feed roller 21, a transport motor 22, a transport roller 23, a platen 24, and a paper discharge roller 25 (see FIGS. 3A and 3B).

  The paper feed roller 21 is a roller for feeding the paper inserted into the paper insertion slot into the printer. The transport roller 23 is a roller that transports the paper S fed by the paper feed roller 21 to a printable region, and is driven by the transport motor 22. The operation of the transport motor 22 is controlled by a controller 60 on the printer side. The platen 24 is a member that supports the paper S being printed from the back side of the paper S. The paper discharge roller 25 is a roller for discharging the paper S to the outside of the printer, and is provided on the downstream side in the transport direction with respect to the printable area.

  The transport motor 22 generates heat when driven (rotated) when transporting the medium. A gear train (not shown) provided for transmitting the driving force of the transport motor 22 to the transport rollers also generates heat due to friction during rotation. That is, it can be said that the transport motor 22 and the gear train are heating elements of the printer 1.

<Carriage unit 30>
The carriage unit 30 is for moving the carriage 31 to which the head unit 40 is attached in the movement direction (also referred to as “scanning”). The carriage unit 30 includes a carriage 31 and a carriage motor (not shown) (FIGS. 3A and 3B).

  The carriage 31 is provided so as to be able to reciprocate in the movement direction in the internal space of the printer 1. The carriage 31 is driven by a carriage motor, and the operation of the carriage motor is controlled by a controller 60 on the printer side. Further, the carriage 31 detachably holds an ink cartridge that stores ink.

  Note that a carriage motor and a gear wheel train (not shown) for moving the carriage 31 using the driving force of the carriage motor generate heat when the carriage 31 moves. That is, it can be said that the carriage motor and the gear train are the heating elements of the printer 1.

<Head unit 40>
The head unit 40 is for ejecting ink onto the paper S. The head unit 40 includes a head 41 having a plurality of nozzles. The head 41 is provided on the carriage 31, and when the carriage 31 moves in the movement direction, the head 41 also moves in the movement direction. Then, when the head 41 is intermittently ejected while moving in the moving direction, dot lines (raster lines) along the moving direction are formed on the paper.

  FIG. 4 is a cross-sectional view showing an example of the structure of the head 41. The head 41 includes a case 411, a flow path unit 412, and a piezo element group PZT. The case 411 houses the piezo element group PZT, and the flow path unit 412 is joined to the lower surface of the case 411. The flow path unit 412 includes a flow path forming plate 412a, an elastic plate 412b, and a nozzle plate 412c. The flow path forming plate 412a is formed with a groove portion serving as a pressure chamber 412d, a through hole serving as a nozzle communication port 412e, a through port serving as a common ink chamber 412f, and a groove portion serving as an ink supply path 412g. The elastic plate 412b has an island portion 412h to which the tip of the piezo element PZT is joined. An elastic region is formed by an elastic film 412i around the island portion 412h. The ink stored in the ink cartridge is supplied to the pressure chamber 412d corresponding to each nozzle Nz via the common ink chamber 412f. The nozzle plate 412c is a plate on which the nozzles Nz are formed. On the nozzle surface, a yellow nozzle row Y for discharging yellow ink, a magenta nozzle row M for discharging magenta ink, a cyan nozzle row C for discharging cyan ink, and a black nozzle row K for discharging black ink are formed. Has been. Each nozzle row is configured by arranging the nozzles Nz at a predetermined interval D in the transport direction.

  The piezo element group PZT has a plurality of comb-like piezo elements (drive elements), and is provided by the number corresponding to the nozzles Nz. A drive signal COM is applied to the piezo element via a wiring board (not shown) on which the head controller HC and the like are mounted, and the piezo element expands and contracts in the vertical direction according to the potential of the drive signal COM. When the piezo element PZT expands and contracts, the island portion 412h is pushed toward the pressure chamber 412d or pulled in the opposite direction. At this time, the elastic film 412i around the island portion 412h is deformed, and the pressure in the pressure chamber 412d rises and falls, thereby ejecting ink droplets from the nozzles.

<Detector group 50>
The detector group 50 is for monitoring the status of the printer 1. The detector group 50 includes a linear encoder 51, a rotary encoder 52, a paper detection sensor 53, an optical sensor 54, and the like (see FIGS. 3A and 3B).

  The linear encoder 51 detects the position of the carriage 31 in the moving direction. The rotary encoder 52 detects the rotation amount of the transport roller 23. The paper detection sensor 53 detects the position of the leading edge of the paper S being fed. The optical sensor 54 detects the presence or absence of the paper S at the opposite position by the light emitting part and the light receiving part attached to the carriage 31, for example, detects the position of the edge of the paper while moving, and sets the width of the paper. Can be detected. The optical sensor 54 also has a leading edge (an end on the downstream side in the transport direction, also referred to as an upper end) and a rear end (an end on the upstream side in the transport direction, also referred to as the lower end) of the paper S depending on the situation. It can be detected.

  In the present embodiment, as the detector group 50, as will be described later, a sensor (sensor 55) for detecting the open / closed state of the cover 11 or a temperature sensor (for example, thermistor: not shown) for detecting the temperature of the heating element. ) Is provided.

<Controller 60>
The controller 60 is a control unit (control unit) for controlling the printer. The controller 60 includes an interface unit 61, a CPU 62, a memory 63, a unit control circuit 64, a head drive circuit 65, and a motor driver 66.

  The interface unit 61 transmits and receives data between the computer 110 that is an external device and the printer 1. The CPU 62 is an arithmetic processing device for performing overall control of the printer 1. The memory 63 is for securing an area for storing a program of the CPU 62, a work area, and the like, and includes a storage element such as a RAM or an EEPROM. Then, the CPU 62 controls each unit such as the transport unit 20 via the unit control circuit 64 in accordance with a program stored in the memory 63.

  The head drive circuit 65 exchanges head drive related information such as transfer of print data and control of print timing between the CPU 62 and the head unit 40. The head drive circuit 65 also generates a drive signal COM (drive waveform) for driving the piezo element PZT. When generating the drive signal COM, the current waveform is amplified using an amplifier in which an NPN transistor and a PNP transistor (both not shown) are configured as push-pull, and a trapezoidal wave having a desired shape is generated. This trapezoidal wave is applied to the head unit 40 to charge / discharge the piezo element PZT. When the piezo element PZT is charged / discharged, the transistor pair generates very high heat, so that it can be said that the head drive circuit 65 is a heating element of the printer 1. The head drive circuit 65 is provided on the printed circuit board 67.

  The motor driver 66 controls the rotation direction, rotation speed, and the like of the transport motor 22 and the carriage motor (not shown). The motor driver 66 incorporates transistors and FETs (not shown), and a current is amplified using a bridge circuit constituted by the transistors and the like when driving various motors. At this time, since the transistor generates very high heat, it can be said that the motor driver 66 is also a heating element of the printer 1.

<Heat dissipation unit 80>
The heat dissipating unit 80 is a heat dissipating device that releases heat generated by a heating element such as the head driving circuit 65 and the motor driver 66 described above to the surrounding atmosphere. Hereinafter, the case where the heat dissipation unit 80 is provided in the head drive circuit 65 that is the highest temperature in the printing operation among the plurality of heating elements described above will be described. The heat radiating unit 80 may be provided for each of the plurality of heat generating elements described above, or designed so that the heat generating elements are arranged as close as possible, and one heat radiating unit 80 common to each heat generating element is provided. You may provide only. The heat radiating unit 80 has a heat radiating body 81.

  The radiator 81 is a metal plate made of aluminum or iron, and releases heat by radiating the heat generated by the heater from the surface of the radiator 81 to the surrounding atmosphere, thereby cooling the heater. The radiator 81 is more likely to emit heat as the contact area with the atmosphere is larger. That is, the larger the surface area, the higher the cooling performance. As shown in FIGS. 3A and 3B, in the present embodiment, the heat radiator 81 is formed in a rectangular plate shape along the carriage movement direction so that the surface area becomes as large as possible.

  Note that the radiator 81 of this embodiment also serves as a rail of the carriage 31 as shown in FIGS. 3A and 3B. The carriage 31 is guided by the heat radiating body 81 along the moving direction and moves in the moving direction. In addition, the printed circuit board 67 is arranged so that the head drive circuit 65 is in contact with the surface (surface on the upstream side in the transport direction) opposite to the surface on the carriage 31 side (surface on the downstream side in the transport direction) of the heat radiator 81. Has been. That is, when viewed from the opening 10 a side, the head drive circuit 65, which is a heating element, is disposed behind the carriage 31.

≪Printing operation of the printer≫
The printing operation of the printer 1 will be briefly described. The controller 60 receives a print command from the computer 110 via the interface unit 61 and controls each unit to perform a paper feed process, a dot formation process, a transport process, and the like.

  The paper feed process is a process of supplying paper to be printed into the printer and positioning the paper at a print start position (also referred to as a cue position). The controller 60 rotates the paper feed roller 21 and sends the paper to be printed to the transport roller 23. Subsequently, the transport roller 23 is rotated, and the paper fed from the paper feed roller 21 is positioned at the print start position.

  The dot formation process is a process for forming dots on paper by intermittently ejecting ink from a head that moves in the movement direction (scanning direction). The controller 60 moves the carriage 31 in the movement direction, and ejects ink from the head 41 based on the print data while the carriage 31 is moving. When the ejected ink droplets land on the paper, dots are formed on the paper, and a dot line composed of a plurality of dots along the movement direction is formed on the paper.

  The carrying process is a process of moving the paper relative to the head in the carrying direction. The controller 60 rotates the transport roller 23 to transport the paper in the transport direction. By this carrying process, the head 41 can form dots at positions different from the positions of the dots formed by the previous dot formation process.

The controller 60 alternately repeats the dot formation process and the conveyance process until there is no more data to be printed, and gradually prints an image composed of dot lines on paper. When there is no more data to be printed, the paper discharge roller is rotated to discharge the paper. The determination of whether or not to discharge paper may be based on a paper discharge command included in the print data.
The same processing is repeated when printing on the next paper, and the printing operation is terminated when not printing.

≪About heat dissipation≫
FIG. 5 is a diagram for explaining a state of heat radiation by the heat radiator 81. In the figure, a head drive circuit 65 is provided on a printed circuit board 67, and the head drive circuit 65 is in contact with a heat radiator 81. The arrows in the figure represent the heat flow during heat dissipation.

  The heat generated by the head drive circuit 65 is dissipated in all directions around a heat source (transistor or the like) represented by the hatched portion in the figure. Since the head drive circuit 65 is formed on the printed circuit board 67, the heat generated by the head drive circuit 65 is also conducted to the printed circuit board 67. That is, when the head drive circuit 65 generates heat, the printed circuit board 67 also generates heat. Therefore, in the following embodiments, the head driving circuit 65 and the printed circuit board 67 may be collectively referred to as a heating element.

  The heat generated in the head drive circuit 65 is conducted from the area where the head drive circuit 65 and the heat radiating body 81 are in contact to the inside of the heat radiating body 81, and further conducted through the heat radiating body 81 to the atmosphere from the opposite surface. Is released. Thereby, the head drive circuit 65 is cooled. In addition, in the heat radiating body 81, the temperature of the portion in contact with the heating element is the highest, and the temperature decreases as the distance from the heating element increases. This is because heat is radiated into the atmosphere in the process of heat conducting inside the radiator 81.

  Further, during printing, the heat generated by the head drive circuit 65 may become an abnormally high temperature (for example, 70 degrees). For this reason, although it is desirable to arrange | position the heat radiator 81 in the position which a user cannot touch, for convenience of apparatus design, the heat radiator 81 may have to be arrange | positioned in the position which a user may touch. . In the present embodiment, when the cover 11 is opened, the internal space of the opening 10a of the housing 10 is opened, so that the user can touch the radiator 81 that is exposed in the internal space. ing. In this case, if an abnormality has occurred in the head drive circuit 65, the temperature of the heat radiating body 81 (particularly, the portion in contact with the head drive circuit 65) may increase, which is dangerous.

  Therefore, in the following embodiment, the safety is improved when the temperature of the head drive circuit 65 becomes abnormal.

≪About processing during printing≫
FIG. 6 is a flowchart of processing during printing in the present embodiment.
First, when receiving a printing command from the computer 110, the controller 60 starts printing by driving each unit to perform the above-described printing operation based on the command (S101).

  At the time of printing, the controller 60 acquires the temperature of the heating element (head drive circuit 65) from a thermistor (not shown) provided in the vicinity of the head drive circuit 65 (S102). And it is judged whether the temperature is below a 1st threshold value (for example, 70 degree | times) (S103).

  When the temperature of the heat generation value exceeds the first threshold value, the controller 60 continues to determine whether or not it is equal to or lower than a second threshold value (for example, 80 degrees) higher than the first threshold value (S104). If it is less than or equal to the second threshold (YES in S104), a first abnormality process described later is executed (S105).

  When the temperature of the heat generation value exceeds the second threshold value, the controller 60 further determines whether or not it is equal to or lower than a third threshold value (for example, 100 degrees) higher than the second threshold value (S106). If it is equal to or less than the third threshold (YES in S106), a second abnormality process described later is executed (S107). On the other hand, if it exceeds the third threshold (NO in S106), a third abnormality process described later is executed (S108).

  If it is determined in step S103 that the temperature of the head drive circuit 65 is equal to or lower than the first threshold (YES in S103), the controller 60 determines whether or not printing is finished (S109). If it is determined that printing has not ended (NO in S109), the process returns to step S102, and the above-described processing is executed again. If it is determined that the printing is finished (YES in S109), the printing process is finished.

≪About the first abnormality process≫
7A and 7B are explanatory diagrams of the first abnormality process. 7A is a view showing a state (closed state) in which the cover 11 is closed, and FIG. 7B is a view showing a state (open state) in which the cover 11 is opened. In the figure, the upper side is the upper side and the lower side is the lower side.

As shown in the figure, a gear 12a, a plate-like member 68, and a sensor 55 are provided as a configuration for performing the first abnormality process.
The gear 12b rotates clockwise or counterclockwise about the axis C2. The rotation operation of the gear 12b is controlled by the controller 60.

  The plate-like member 68 is provided at the upper end of the printed circuit board 67. On the upper surface of the plate-like member 68, a linear gear 68a in which teeth are linearly arranged along the transport direction is formed. The linear gear 68a is provided so as to mesh with the gear 12b, and the plate member 68 moves in the transport direction along a guide (not shown) according to the direction of rotation of the gear 12b. Specifically, when the gear 12b rotates in the clockwise direction, the plate-like member 68 (and the printed circuit board 67) moves downstream in the transport direction. Conversely, when the gear 12b rotates in the counterclockwise direction, the plate-like member 68 (and the printed circuit board 67) moves to the upstream side in the transport direction.

The sensor 55 is a push button type sensor, and outputs a signal indicating whether the cover 11 is in a closed state or an open state to the controller 60 according to whether or not the button is pressed.
For example, as shown in FIG. 7A, when the cover 11 is closed, the sensor 55 is pressed by the cover 11. At this time, the sensor 55 outputs a signal indicating that the cover 11 is closed to the controller 60.
On the other hand, as shown in FIG. 7B, when the cover 11 is opened by the user, the pressing of the sensor 55 by the cover 11 is released. At this time, the sensor 55 outputs a signal indicating that the cover 11 is open to the controller 60.

FIG. 8 is a flowchart showing an example of the first abnormality process.
Note that at the start of the first abnormality process, the cover 11 is in a closed state, and the heating element and the heat dissipation element 81 are in contact with each other.

  When it is determined in step S104 of FIG. 6 that the temperature of the heating element is equal to or lower than the second threshold, the controller 60 acquires the output of the sensor 55 (S11). Then, the controller 60 determines whether the cover 11 is open or closed. That is, it is determined whether or not the cover 11 is open (S12). When it is determined that the cover is in the closed state (NO in S12), the controller 60 maintains a state in which the heat generating body and the heat radiating body 81 are in contact (S13). And it returns to step S11 and the output of the sensor 55 is acquired again.

  On the other hand, when it is determined in step S12 that the cover is in the open state (YES in S12), the controller 60 rotates the gear 12b counterclockwise about the axis c2. As a result, the heating elements (printed circuit board 67 and head drive circuit 65) move upstream in the transport direction. Thus, in conjunction with the operation of opening the cover 11, the heating element and the radiator 81 are separated (S14). And step S11 which acquires the output of sensor 55 is performed again.

  If it is determined in step S12 that the cover 11 is in the closed state (NO in S12), the controller 60 performs the reverse operation to the case of opening the cover. That is, by receiving a signal indicating that the cover 11 is in the closed state from the sensor 55, the controller 60 rotates the gear 12b in the clockwise direction about the axis c2. As a result, the heating elements (printed circuit board 67 and head drive circuit 65) move downstream in the transport direction. In this way, the heating element and the radiator 81 are brought into contact as shown in FIG. 7A (S13).

  As described above, in the first abnormality process, the heating element (head drive circuit 65) and the radiator 81 are separated from each other in conjunction with the operation of opening the cover. Thereby, when the cover 11 is opened, the heat radiating body 81 is cooled, so that safety can be improved.

<Modification of the first abnormality process>
9A and 9B are explanatory diagrams of a modified example of the first abnormality process. 9A is a view showing a state (closed state) in which the cover 11 is closed, and FIG. 9B is a view showing a state (open state) in which the cover 11 is opened. In the figure, the upper side is the upper side and the lower side is the lower side. 9A and 9B, parts having the same configurations as those in FIGS. 8A and 8b are denoted by the same reference numerals and description thereof is omitted.

In this modification, a heat radiator 82 (corresponding to a preliminary heat radiator) separate from the heat radiator 81 is provided.
The radiator 82 is provided inside the housing 10 behind the radiator 81 and the printed circuit board 67 when viewed from the cover 11 side. Therefore, even if the cover 11 is opened, the radiator 82 is not exposed. The heat radiator 82 is made of a material having a lower heat radiation efficiency than the heat radiator 81. Normally, the heat radiating body 81 having a high heat dissipation efficiency described above is used to dissipate heat generated by the heat generating body, and the heat radiating body 82 is used in an emergency where the heat radiating body 81 cannot be used.

Next, the operation of the modified example of the first abnormality process will be described with reference to FIGS. 9A and 9B.
As shown in FIG. 9A, the sensor 55 is pressed by the cover 11 when the cover 11 is closed (closed state). At this time, the sensor 55 outputs a signal indicating that the cover 11 is closed to the controller 60. At this time, the controller 60 moves the head drive circuit 65 to a position where it comes into contact with the heat radiating body 81. For this reason, when the head drive circuit 65 is at a high temperature, the radiator 81 is also at a high temperature (for example, 70 degrees).

  On the other hand, as shown in FIG. 9B, when the cover 11 is opened by the user, the pressing of the sensor 55 by the cover 11 is released. At this time, the sensor 55 outputs a signal indicating that the cover 11 is open to the controller 60. When the controller 60 receives a signal indicating that the cover 11 is in the open state, the controller 60 rotates the gear 12b counterclockwise about the axis c2. As a result, the heating elements (printed circuit board 67 and head drive circuit 65) move upstream in the transport direction. In this way, in conjunction with the operation of opening the cover 11, the heating element is separated from the radiator 81 and contacts the radiator 82.

  When closing the cover, the controller 60 performs the reverse operation of opening the cover. That is, when receiving a signal indicating that the cover 11 is in the closed state from the sensor 55, the controller 60 rotates the gear 12b in the clockwise direction around the axis c2. As a result, the heating elements (printed circuit board 67 and head drive circuit 65) move downstream in the transport direction. Thus, the heating element is separated from the radiator 82 and contacts the radiator 81 (FIG. 9A).

  Since the heat radiating body 82 has lower heat radiating efficiency than the heat radiating body 81, in this embodiment, the heat radiating body 82 is used urgently when the cover 11 is opened (that is, when the heat generating body and the heat radiating body 81 are separated). Usually, the heat radiator 81 with high heat radiation efficiency is used. By providing a plurality of heat dissipating bodies in this manner and switching and using them according to the opening and closing of the cover 11, safety can be improved while suppressing the influence of heat from the heat generating elements.

≪About the second abnormality process≫
FIG. 10 is a flowchart of the second abnormality process. As described above, the thermistors (both not shown) are provided in the vicinity of the head drive circuit 65 and in the vicinity of the transport motor 22 (corresponding to a paper feed motor).
When the detected temperature of the head drive circuit 65 by the thermistor is equal to or lower than the third threshold value in step S106 in FIG. 6 (YES in S106), the controller 60 covers the head drive circuit 65 when the carriage 31 is viewed from the opening 10a side. It moves to a position and stops (FIG. 10, S21). At this time, the controller 60 moves the carriage 31 without ejecting ink from the head 41. As a result, the driving of the head drive circuit 65, which is a heating element, can be stopped quickly, so that safety can be further improved.

FIG. 11 is a simplified explanatory diagram of the carriage stop position in the second abnormality process. FIG. 11 is a view of the printer 1 as seen from above.
In the second abnormality process, as shown in FIG. 11, the controller 60 stops the carriage 31 at a position that covers the head drive circuit 65 (heating element) when viewed from the opening 10a side. By doing so, even if the user puts his hand through the opening 10a, it is difficult to touch the portion of the heat radiating body 81 having the highest temperature (contact portion with the head drive circuit 65). Therefore, safety can be improved. In the present embodiment, the carriage 31 completely covers the head drive circuit 65, but the present invention is not limited to this. For example, when the head drive circuit 65 is disposed on the left side (left side in the drawing) of the opening 10a, the carriage may be stopped so as to cover a part on the right side of the head drive circuit 65. Even in this case, even if the user puts his hand through the opening 10a, it is difficult to touch the portion of the radiator 81 where the temperature is highest.

  After step S21 in FIG. 10, the controller 60 subsequently acquires the temperature of the transport motor 22 from a thermistor provided in the vicinity of the transport motor 22 (paper feed motor) (S22), and the temperature is a specific threshold value (S22). It is determined whether or not (for example, 70 degrees) or less (S23). When the temperature of the transport motor 22 is equal to or lower than the threshold (YES in S23), the controller 60 discharges the paper being printed (S24) and turns off the power (S25). On the other hand, if the temperature of the transport motor 22 exceeds the threshold value in step S106 (NO in S23), step S25 is executed to turn off the power without driving the transport motor 22 (that is, without discharging the paper). To do. By doing so, the safety can be further improved.

  In this embodiment, after the carriage 31 is stopped at a predetermined position, the paper being printed is discharged and the power is turned off. However, the present invention is not limited to this. For example, an error may be displayed on a display (not shown).

  As described above, in the present embodiment, the carriage 31 is stopped at a position that covers the head driving circuit 65 when viewed from the opening 10a side in accordance with the temperature of the heating element (head driving circuit 65) (second). Abnormal processing). By doing so, even if the temperature of the head drive circuit 65 is abnormal, it becomes difficult for the user to touch the portion of the radiator 81 where the temperature is highest. Therefore, safety can be improved.

<Modification 1 of the second abnormality process>
In the second abnormality process described above, the carriage 31 is stopped so as to cover the head drive circuit 65 when viewed from the opening 10a side. In the first modification of the second abnormality process, the position of the head drive circuit 65 and the position where the carriage 31 is stopped are different from the second abnormality process. Since the other configuration and the processing at the time of abnormality are the same as those of the second abnormality processing, description thereof will be omitted.

  FIG. 12 is a simplified explanatory diagram of the carriage stop position in the first modification of the second abnormality process. As shown in the figure, in the first modification, the positions of the head drive circuit 65 and the opening 10a in the moving direction are deviated from the second abnormality process described above. Specifically, the head drive circuit 65 is provided so that the position in the movement direction overlaps the housing 10 on the left side of the drawing with respect to the opening 10a.

In the case of the first modification, the controller 60 moves and stops the carriage 31 to a position covering the left side of the opening 10a when viewed from the opening 10a according to the temperature of the head drive circuit 65.
In this case, the head drive circuit 65 and the carriage 11 are displaced from each other in the moving direction. However, even if the user puts his hand through the opening 10a, the portion of the radiator 81 that has the highest temperature (the contact with the head drive circuit 65) Part) is difficult to touch. Therefore, also in the first modification of the second abnormality process, safety can be improved.

<Second Modification of Second Abnormal Processing>
Also in the second modification of the second abnormality process, the position of the head drive circuit 65 and the position where the carriage 31 is stopped are different from those of the above-described embodiment. Since other configurations and processes are the same as those in the above-described embodiment, the description thereof is omitted.

  FIG. 13 is a simplified explanatory diagram of the carriage stop position in the second modification of the second abnormality process. As shown in the figure, in the second modification, the head drive circuit 65 is provided further to the left (position away from the opening 10a) than in the second embodiment.

  In the second modification, the controller 60 stops the carriage 31 so that at least a part of the carriage 31 is positioned between the head drive circuit 65 and the opening 10 a according to the temperature of the head drive circuit 65. In the case of FIG. 13, the stop position (position in the movement direction) of the carriage 31 is between the head drive circuit 65 and the opening 10a. That is, the position of the carriage 31 in the moving direction does not overlap with the head drive circuit 65 (heating element) or the opening 10a. It becomes difficult to touch the part. Therefore, also in the second modification of the second abnormality process, safety can be improved.

≪About the third abnormality process≫
FIG. 14 is a flowchart of the third abnormality process.
If the detected temperature of the head drive circuit 65 by the thermistor exceeds the second threshold value in step S106 of FIG. 6 (NO in S106), the controller 60 locks with the cover 11 closed (S31). As a result, the cover 11 cannot be opened, and the user cannot completely touch the members in the internal space. Therefore, safety can be improved.
Thereafter, the controller 60 turns off the power (S32).
In the present embodiment, the power is turned off after the cover 11 is locked, but the present invention is not limited to this. For example, an error may be displayed on a display (not shown).

=== Modification of First Embodiment ===
In the above-described embodiment, when the heat generation temperature of the heat generator exceeds the first threshold value (predetermined value), three abnormal processes are performed according to the temperature, but the present invention is not limited to this. For example, the second abnormality process may be omitted and the two abnormality processes of the first abnormality process and the third abnormality process may be performed. Or you may abbreviate | omit a 3rd abnormality process and perform two abnormality processes, a 1st abnormality process and a 2nd abnormality process. Furthermore, four or more abnormal processes may be performed according to the temperature.

  Further, the order of execution of the abnormality processing is not limited to the above-described embodiment. For example, the order of the first abnormality process and the second abnormality process may be reversed. In short, when the temperature of the heating element exceeds the first threshold value, any one of a plurality of predetermined abnormality processes may be executed according to the temperature.

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

<About the printer>
In the above-described embodiment, a printer (serial printer) that repeatedly performs a transport operation for transporting a medium in the transport direction and a dot formation operation for forming dots on the medium by ejecting ink from the nozzles while moving the head in the movement direction. However, it is not limited to this. For example, a line printer that includes a nozzle row that is longer than the medium width in the medium width direction and prints an image on the medium by ejecting ink from each nozzle of the nozzle row while the medium is being conveyed in the conveyance direction may be used.

<About piezo elements>
In the above-described embodiment, ink is ejected using a piezo element. However, the method of ejecting the liquid is not limited to this. For example, other methods such as a method of generating bubbles in the nozzle by heat may be used.

1 printer, 10 housing, 10a opening, 11 cover,
20 transport units, 21 paper feed rollers, 22 transport motors,
23 transport roller, 24 platen, 25 discharge roller,
30 Carriage unit, 31 Carriage,
40 head units, 41 heads, 411 case, 412 flow path unit,
412a flow path forming plate, 412b elastic plate, 412c nozzle plate,
412d pressure chamber, 412e nozzle communication port, 412f common ink chamber,
412g Ink supply path, 412h island part, 412i elastic film,
50 detector groups, 51 linear encoder, 52 rotary encoder,
53 Paper detection sensor, 54 Optical sensor,
60 controller, 61 interface, 62 CPU,
63 memory, 64 unit control circuit, 65 head drive circuit,
66 motor driver, 67 printed circuit board,
80 heat radiating unit, 81 heat radiating body,
110 computer

Claims (7)

A housing,
A cover provided in the housing and capable of opening an internal space;
A heating element provided inside the housing;
A radiator that dissipates heat generated by the heating element, the radiator being provided with at least a portion exposed in the internal space; and
A detector for detecting the temperature of the heating element;
With
A plurality of abnormality processes are defined for a case where the detection result of the detection unit exceeds a predetermined temperature, and when the detection result exceeds the predetermined temperature, the plurality of abnormality processes are determined according to the magnitude of the detection result. Execute one of the abnormal processes,
A printing apparatus characterized by that. The printing apparatus according to claim 1,
At least one of the plurality of abnormal processes is to separate the heat generating body and the heat radiating body in conjunction with an operation of opening the cover. The printing apparatus according to claim 2,
A spare heat radiator different from the heat radiator is provided inside the housing,
A printing apparatus, wherein the heating element and the heat radiating body are separated from each other and the heating element and the auxiliary heat radiating body are brought into contact with each other in conjunction with an operation of opening the cover. The printing apparatus according to claim 1,
An opening provided in the housing;
A carriage provided inside the housing so as to be movable in a predetermined direction, wherein the carriage is provided in front of the heating element at a position from the opening;
Further comprising
At least one of the plurality of abnormal processes is to stop the carriage at a position covering at least a part of the heating element when viewed from the opening side. The printing apparatus according to claim 1,
An opening provided in the housing;
A carriage provided inside the housing so as to be movable in a predetermined direction, wherein the carriage is provided in front of the heating element at a position from the opening;
Further comprising
At least one of the plurality of abnormality processes is to stop the carriage at a position covering at least a part of the opening as viewed from the opening. The printing apparatus according to claim 1,
An opening provided in the housing;
A carriage provided inside the housing so as to be movable in a predetermined direction, wherein the carriage is provided in front of the heating element at a position from the opening;
Further comprising
At least one of the plurality of abnormal processes is to stop the carriage so that at least a part of the carriage is positioned between the heating element and the opening. The printing apparatus according to claim 1,
At least one of the plurality of abnormality processes is to lock the cover in a closed state.

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