JP2010143154A - Recording device, recording head, and head substrate thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve tolerance against noise in data transmission through a low voltage differential transmitting line connecting a device body to a carriage (recording head). <P>SOLUTION: A recording device is provided with flexible cable connecting a control circuit to the carriage. A plurality of signal lines include a power source line and the low voltage differential transmitting line. The carriage is provided with a carriage side connector connecting the low voltage differential transmitting line, and a receiver provided near the carriage side connector and receiving the signals sent from a transmitter via the carriage side connector and low voltage differential transmitting line. In the flexible cable, a paired lines of the low voltage differential transmitting line are closely disposed to each other, the power source line is separately disposed from the paired lines. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a recording apparatus including a recording head having a plurality of recording elements, a recording head, and a head substrate thereof.

  2. Description of the Related Art Recording apparatuses that record information such as characters and images on a sheet-like recording medium such as paper or film are known. Recording apparatuses are widely used in government offices, offices, and personal use, and high density and high speed recording are strongly desired. On the other hand, development and improvement have been attempted to achieve cost reduction or higher definition.

  Among the recording apparatuses described above, an inkjet recording type recording apparatus (hereinafter referred to as an inkjet recording apparatus) is known as a low-noise non-impact recording. The ink jet recording apparatus performs recording by ejecting ink from an ejection port arranged in a recording element. Ink jet recording apparatuses are capable of high density and high speed recording due to their structural features, and are widely used as low-cost color printers. An ink jet recording apparatus performs recording using a recording head including a recording element (nozzle) having an electrothermal conversion element. The electrothermal conversion element generates ejection energy for ejecting ink from the ejection port and the ejection port.

  As a configuration of the recording head, a plurality of recording elements are arranged in one or a plurality of rows. In such a recording head, several or several tens of driving integrated circuits that can be driven simultaneously with N recording elements as one block are mounted on the same substrate. Then, the recording data is aligned corresponding to each recording element, and the recording element is driven. Arbitrary information can be recorded on the recording medium by driving the recording element.

  With recent high definition and improved recording quality, the performance of the recording head has been remarkably improved. The number of recording elements that are simultaneously driven is increasing in order to increase the number of recording elements and increase the recording speed. Further, the performance of the recording element has also been improved, and several picoliters of ink can be ejected with a pulse width of about 1 microsecond. This is achieved by a functional element (such as a MOS-FET driver) that switches a large current at high speed.

  In addition to this, improvements have also been made in recording data transfer. In recording data transfer, a current is selectively applied to the recording element. The recording data transfer frequency exceeds 10 megahertz. Further, in order to achieve high-speed data transfer, it has been devised so that the recording data can be shifted not only at the rising edge of the recording data transfer clock but also at the falling edge. If, however, the transfer of print data is not in time within the ink discharge period from the print element, the print data lines are transferred in parallel and parallel processing is performed at the same clock frequency.

  Further, in the recording apparatus, it is necessary to transfer not only the recording data but also various data and control information at high speed. Such information includes, for example, information for identifying the type of the print head. In addition to this, information on the recording head includes, for example, information on the amount of ink used in the case of an inkjet recording head.

  In the recording head, as the number of recording elements driven simultaneously increases, the energy required for driving increases. For this reason, it is necessary to perform drive control of the printing element in accordance with the capacity of the power supply circuit of the printing apparatus main body. In the case of a recording element that performs recording using heat, when one recording element is driven continuously, the heat is accumulated, and the recording density may change or the recording element itself may be damaged. There is sex. In particular, when there is a factor such as manufacturing variation, the energy applied to the recording element is not appropriate, and the durability of the recording head is reduced.

  Further, the recording element is also affected by recording elements adjacent to the recording element. For example, in an ink jet recording apparatus, when adjacent recording elements are driven simultaneously, each nozzle receives interference due to the mutual pressure due to the pressure generated during ink ejection. This pressure interference (crosstalk) may cause a change in recording density. For this reason, it is desirable to control the drive after driving the recording element, either by radiating heat to some extent or by avoiding the use for a time to avoid crosstalk. In addition, drive control is required in accordance with the amount of recording agent used in a cartridge containing a recording agent such as ink, particularly the amount of ink cartridge used in an ink jet recording head. This requirement varies widely, such as differences depending on ink color information and date of manufacture, differences due to ink viscosity, and differences depending on usage.

  In order to cope with the above-mentioned problems and requirements, the recording head includes a means for detecting the temperature of the recording head, a means for arbitrarily changing the driving method with an external input signal, a means for detecting a recording head difference due to manufacturing variations, etc. Is provided. A method has been proposed in which various information is acquired as necessary using these means, and drive control of the recording head is performed based on the information (see Patent Document 1).

  Also, a circuit configuration in which the recording element group is divided into a plurality of blocks composed of a predetermined number of recording elements and time-division driving is performed for each block has been put into practical use. As described above, in the vicinity of the recording head unit, various control methods have been introduced and the processing system has become complicated as the recording apparatus has become highly functional.

  As described above, the number of recording elements provided in the recording head tends to increase. Therefore, for example, when the number of blocks in time-division driving increases, the number of control signal lines increases even if a decoder circuit or the like is used. For example, when a clock signal having a logic level of 5 volts or 3.3 volts is transferred at several tens of megahertz, the influence of the radiated noise on the peripheral devices and the influence on the control data line of the recording apparatus are increased.

  Further, as described above, the recording apparatus must perform high-speed switching of a large current passing through the recording element. Switching noise (induced electromotive force) is generated beyond the logic level from the power supply terminal, and affects nearby logic signal series wiring. This state affects recording data and clock signals as well as control data lines and the like, causing malfunctions in the control circuit. This malfunction is caused by a problem in the configuration of the recording apparatus, and is manifested as a recording abnormality, for example. In order to cope with such noise, a technique is known in which the ground terminal of the logic circuit and the ground terminal of the power supply line are separated as much as possible and short-circuited at the power supply terminal of the recording apparatus. However, in this method, the influence of the jumping noise occurs due to the downsizing of the recording apparatus. Here, the level of this jumping noise changes as the carriage mounting the recording head moves. This is because when the carriage moves at high speed, the shape of the wiring board of the flexible cable connecting the carriage and the recording apparatus main body changes accordingly. The higher the recording quality and function, the more complicated the configuration of the recording head and the surrounding control devices. Therefore, in the control unit of the recording apparatus main body, the control is complicated such as countermeasures against malfunction due to noise, and a large load is generated.

  For example, the control unit of the recording apparatus main body manages and executes a control sequence such as changing the drive pattern in accordance with the operation mode of the recording head. In the control unit of the recording apparatus main body, for example, when manufacturing variations or lot differences of the recording head are large, the difference in the recording state is reflected in the recording result remarkably. The model identification and driving status of the system are monitored sequentially. Thus, it is necessary to always perform data communication between the recording apparatus main body and the recording head. Further, noise that jumps into the control data line connecting the two causes a fatal malfunction in the recording apparatus.

There is known a technique in which a differential input circuit is applied to a control data line that transmits a signal directly related to a recording abnormality, such as a recording data signal, a clock signal, a latch signal, and a reset signal (see Patent Document 2). According to this technique, even if noise is generated by switching when driving the recording element, the noise is canceled out in the control data line due to the same phase.
Japanese Patent Application Laid-Open No. 7-241992 Japanese Patent Laid-Open No. 10-166583 JP 2002-326348 A

  In recording devices, the number of recording elements increases with improved recording quality, large-capacity recording data and control data as the recording head speeds up, recording head model identification, and drive status monitoring Therefore, it is necessary to perform data communication at high speed.

  However, according to the technique described in Patent Document 2, a signal having a level equivalent to the logic level for driving these logic circuits is transmitted in the control data line between the printing apparatus main body and the carriage or the printing head. Data rate will be lowered. This is caused by waveform deterioration due to inductance and impedance of the control data line. In addition, if transmission delay occurs, there is a possibility that radiation noise that causes not only the recording apparatus but also its peripheral devices to malfunction, such as the influence of EMI due to high-frequency transfer, will increase.

  In order to cope with this, a recording apparatus using low voltage differential transmission for a control data line is known (see Patent Document 3). In a future recording apparatus, it is important how to transfer recording data having a large capacity between the recording apparatus main body and the recording head. This method according to the LVDS (low voltage differential signaling) technology can be said to be an effective method. However, there are some problems in applying this method to a recording apparatus.

  First, the arrangement of the LVDS transmitter and its receiver can be mentioned. When transferring the recording data from the recording apparatus main body to the recording head, the effect may not be sufficiently exhibited depending on the arrangement of the pair wiring of the low voltage differential transmission line. This is because the recording apparatus generates various noises such as high-frequency noise and common mode noise caused by recording current application. In the recording apparatus, the low-voltage differential transmission line can coexist with a power supply line that turns on and off a large current passed through the recording head at high speed and another logical transmission line. These problems are peculiar to a recording apparatus that separates and controls a recording head that conducts a large current from the main body of the recording apparatus. However, it is required to solve such problems for the future.

  Therefore, the present invention has been made in view of the above problems, and the apparatus main body and the carriage (recording head) are connected by a low-voltage differential transmission line, and resistance to noise of data transmission via the line is achieved. It is an object to provide a technique that improves the performance.

  In order to achieve the above object, a recording apparatus according to one embodiment of the present invention includes a control circuit provided in a main body of the apparatus, a carriage on which a recording head having a plurality of recording elements is mounted, and a space between the control circuit and the carriage. And a flexible cable having a plurality of signal lines for transmitting various signals, and the plurality of signal lines are transmitted by a low voltage differential transmission system and a power line for supplying power to drive the recording element. A low voltage differential transmission line consisting of a pair wiring for performing, the control circuit is provided in the vicinity of the control circuit side connector for connecting the low voltage differential transmission line, the control circuit side connector, A transmitter for transmitting a signal via the control circuit side connector and the low voltage differential transmission line, and the carriage includes the low voltage differential transmission line. And a receiver provided near the carriage-side connector and receiving a signal sent from the transmitter via the carriage-side connector and the low-voltage differential transmission line. In the flexible cable, the pair wirings of the low-voltage differential transmission line are arranged close to each other, and the power supply line is arranged separately from the pair wiring.

  Another aspect of the present invention is a flexible signal line including a power line that supplies power used to drive a recording element and a low-voltage differential transmission line that includes a pair wiring that performs transmission using a low-voltage differential transmission system. A recording head connected to a recording apparatus by a cable, a connector for connecting the low-voltage differential transmission line, and provided near the connector, via the connector and the low-voltage differential transmission line A receiver for receiving a signal sent from the recording device, and the flexible cable has a pair of low-voltage differential transmission lines arranged close to each other, and the power line is connected to the pair wiring. It is characterized by being arranged separately.

  Another aspect of the present invention is a flexible signal line including a power line that supplies power used to drive a recording element and a low-voltage differential transmission line that includes a pair wiring that performs transmission using a low-voltage differential transmission system. A head substrate of a recording head connected to a recording apparatus by a cable, a connector for connecting the low-voltage differential transmission line, and provided in the vicinity of the connector, the connector and the low-voltage differential transmission line A receiver for receiving a signal sent from the recording device via the cable, and the flexible cable is provided with a pair of low-voltage differential transmission lines arranged close to each other, and the power line is connected to the power line. It is characterized by being arranged separately from the pair wiring.

  According to the present invention, the apparatus main body and the carriage (recording head) are connected by the low-voltage differential transmission line, and the resistance to noise of data transmission through the line is improved. Thereby, it is possible to realize a highly reliable recording apparatus that is not easily affected by radiation noise or external noise.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the following description, a recording apparatus using an inkjet recording method will be described as an example, but the present invention is not limited to this. The recording apparatus using the ink jet recording method may be, for example, a single function printer having only a recording function, or a multi-function printer having a plurality of functions such as a recording function, a FAX function, and a scanner function. There may be.

  In this specification, “recording” is not limited to the case of forming significant information such as characters and figures, but may be significant or insignificant. Further, it also represents a case where an image, a pattern, a pattern, or the like is widely formed on a recording medium or a medium is processed regardless of whether or not it is manifested so that a human can perceive it visually.

  “Recording medium” refers not only to paper used in general recording apparatuses but also widely to cloth, plastic film, metal plate, glass, ceramics, wood, leather, and the like that can accept ink. .

  Further, “ink” should be interpreted widely as in the definition of “recording”. Therefore, by being applied on the recording medium, it can be used for forming an image, pattern, pattern, etc., processing the recording medium, or processing the ink (for example, coagulation or insolubilization of the colorant in the ink applied to the recording medium). Represents a liquid that can be provided. Further, the “nozzle” collectively refers to an ejection port, a liquid path communicating with the ejection port, and an element that generates energy used for ink ejection unless otherwise specified.

  First, an example of the external configuration of a recording apparatus according to an embodiment of the present invention will be described with reference to FIG.

  The lead screw 5004 rotates in conjunction with the forward / reverse rotation of the carriage motor 5013. This rotation is transmitted to the lead screw 5004 via the driving force transmission gears 5011 and 5009.

  The carriage HC has a pin (not shown) that engages with the spiral groove 5005 of the lead screw 5004 and reciprocates in the directions of arrows a and b as the lead screw 5004 rotates. An ink jet cartridge IJC is mounted on the carriage HC. The ink jet cartridge IJC is provided with an ink tank IT for storing a recording head IJH and recording ink. The recording head IJH includes a monochrome recording head and a color recording head, but any recording head may be used. In the case of a recording head for monochrome recording, an ink tank IT containing monochrome ink (black ink) is mounted. In the case of a recording head for color recording, for example, four ink tanks IT that contain four types of inks of yellow, magenta, cyan, and black are mounted. The ink jet cartridge IJC may be an integral type of ink tank and recording head, or may be configured such that the ink tank and recording head can be separated.

  Reference numeral 5002 denotes a paper pressing plate that presses the recording medium (recording paper P) against the platen 5000 along the moving direction of the carriage HC. The platen 5000 is rotated by a transport motor (not shown) and transports the recording paper P. Reference numeral 5016 denotes a member that supports a cap member 5022 that caps the front surface of the recording head IJH. Reference numeral 5015 denotes suction means for sucking the inside of the cap, and performs suction recovery of the recording head IJH through the opening 5023 in the cap.

  Next, an example of the internal configuration of the recording apparatus shown in FIG. 1 will be described with reference to FIG.

  Reference numeral 1700 denotes an interface for inputting a recording signal (hereinafter referred to as recording data), 1701 denotes an MPU, and 1702 denotes a ROM that stores a control program executed by the MPU 1701. Reference numeral 1703 denotes a DRAM that stores various data (recording data input from the interface, expanded recording data supplied to the recording head IJH, and the like). Reference numeral 1704 denotes a gate array (GA) that controls supply of print data to the printhead IJH. The gate array 1704 also performs data transfer control among the interface 1700, the MPU 1701, and the RAM 1703. The above is the configuration of the control circuit 10 on the recording apparatus side.

  Reference numeral 1709 denotes a conveyance motor for conveying the recording paper P. Reference numeral 1706 denotes a motor driver for driving the carry motor 1709, and 1707 denotes a motor driver for driving the carriage motor 5013.

  The operation of the above configuration will be briefly described. When print data is input to the interface 1700, the print data is converted into data corresponding to the print ink color between the gate array 1704 and the MPU 1701. Then, the motor drivers 1706 and 1707 are driven. At the same time, the carriage-side control circuit 20 drives and controls the recording head IJH according to the received recording data. As a result, information based on the recording data input to the interface 1700 is recorded on the recording paper P. At the time of this recording, it is necessary to drive the recording element provided in the recording head IJH under optimum driving conditions. Therefore, at the time of recording, the characteristic information held in the memory 131 of the recording head substrate 103 in the recording head IJH is referred to, and the driving condition of each recording element is determined.

  The recording head substrate 103 is provided with, for example, a plurality of recording elements, a drive circuit (for example, a power transistor) that drives the recording elements, and a logic circuit. The logic circuit includes a shift register, a latch circuit, an AND circuit, a decoder circuit, and the like, and selectively drives the drive circuit. The recording element according to the present embodiment will be described by taking as an example a case where the recording element is composed of an electrothermal conversion element (which generates thermal energy for ejecting ink), but this structure is not particularly limited. You may comprise with an element.

  3 and 4 are diagrams showing an outline of a transmission line between the control circuit 10 on the recording apparatus side and the recording head IJH mounted on the carriage HC. Here, two examples are given.

  The configuration shown in FIG. 3 corresponds to the configuration shown in FIG. 2, and a control signal from the control circuit 10 is supplied to the recording head IJH via the carriage-side control circuit 20. 4 directly supplies the control signal from the control circuit 10 to the recording head IJH.

(Embodiment 1)
Here, the first embodiment will be described. FIG. 5 shows a control circuit 10 and a carriage-side control circuit 20 as functional configurations in the recording apparatus shown in FIG. Note that the power supply line connecting the two is shown in a large pattern for easy understanding. In order to draw out the effect of the low-voltage differential transmission line more, there is a contrivance that the pair wiring is not bent at a right angle. However, here, the schematic wiring is a right-angle wiring.

  Here, the control circuit 10 includes a power supply unit 11, a drive control unit 12, and a recording data control unit 13. Further, the control circuit 10 is provided with a connector (control circuit side connector) as connection means for connecting to a flexible cable (also called a flexible substrate). An LVDS (low voltage differential signaling) transmitter is provided near the connector (for example, within 1 inch). The LVDS transmitter maximizes the effect of the low-voltage differential transmission line (hereinafter referred to as the LVDS line) by suppressing the routing of the pair wiring as much as possible. The LVDS line is composed of a pair wiring that performs transmission by a low voltage differential transmission system.

  On the other hand, an LVDS receiver is provided on the recording head IJH side. There are various configurations for incorporating the LVDS receiver. In this embodiment, the LVDS receiver is disposed in the carriage-side control circuit 20 of the carriage HC. The carriage-side control circuit 20 is also provided with a connector (carriage-side connector) as a connecting means to which a flexible cable is connected, and an LVDS receiver is provided near the connector (for example, within 1 inch).

  The layout on the flexible cable shown in FIG. 5 shows an outline of the wiring layout of the flexible cable. The LVDS line and the power supply line are completely separated at a distance. There should be a partition for the installed conductor (ground terminal wiring) between the two if possible. Originally, the shield line is desirable for the LVDS line, but it is difficult to use the shield line in the recording apparatus. Therefore, in the case of a recording apparatus using a flexible cable, the wiring layout shown in FIG. 5 is preferable. The flexible cable has, for example, a planar shape, and a plurality of signal lines are arranged along a predetermined direction of the same planar shape. The pair wiring (pair part) of the LVDS line is close to each other, and the pair wiring of the LVDS line is separated from the pair wiring of the other LVDS line and the normal signal line by the installation conductor (ground terminal wiring). To do. The LVDS line pair wiring is preferably arranged at a position other than the end of the flexible cable, and, for example, a ground terminal wiring is preferably arranged at the end. This is for maintaining the balance of the pair wiring of the LVDS line.

  FIG. 6 is a diagram schematically showing a control communication system in the control circuit 10 and the carriage-side control circuit 20 shown in FIG.

  Here, the rectangular frame shown with the dotted line in the figure has shown the flexible cable (FPC). The flexible cable has a plurality of signal lines that connect the recording apparatus main body (control circuit 10) and the carriage HC (recording head IJH) and transmit various signals. The flexible cable includes, for example, a power supply line, a recording data line (DATA), a data transfer clock line (CLK), a latch signal line (LATCH), and a control series wiring. The power supply line is a wiring for supplying a current (recording element driving current) to the recording head IJH, and the recording data line (DATA) is a wiring for transferring recording data to the recording head IJH. The latch signal line (LATCH) is a wiring for sending a latch signal for temporarily holding recording data in the recording head IJH, and the control series wiring is for performing pulse width control in energizing the recording element. Wiring.

  Reference numeral 11 denotes a power supply unit that supplies power to the recording head IJH. Reference numeral 13 denotes a recording data control unit that generates recording data, a clock signal, a latch signal, and the like. Reference numeral 12 denotes a drive control unit that generates a signal related to drive control of the recording head IJH such as a heat enable signal and a block selection signal, 14 denotes an LVDS transmitter on the recording apparatus main body side, and 21 denotes a carriage side control circuit 20. LVDS receiver. The LVDS transmitter 14 transmits a signal via the LVDS line, and the LVDS receiver 21 receives a signal transmitted from the LVDS transmitter 14 via the LVDS line. Note that the wiring and configuration after the LVDS receiver of the carriage-side control circuit 20 are the same as those in the prior art, and a description thereof will be omitted.

  Since the transfer frequency of the recording data is more than a dozen megahertz, in this embodiment, as shown in FIG. 6, LVDS lines are connected to the recording data signal line (DATA) and the data transfer clock line (CLK) of this series. Used. Further, the differential transmission method is also used for the latch signal line (LATCH). This is because if the same kind of noise is mixed in the latch signal line, a recording abnormality is caused.

  When a signal current is transmitted to one side of a pair of LVDS lines, the same amount of signal current flows in the opposite direction in the other line. Thus, since the current returns in the transmission line pair, the loop area due to the current is small, and the generated radiation noise is also small.

  A portion corresponding to the LVDS receiver 21 on the other side of the LVDS line is provided in the circuit of the carriage-side control circuit 20. The LVDS receiver 21 detects a differential signal of several tens of mV and amplifies the signal to the amplitude of the drive voltage for driving the control circuit of the recording head IJH. In this embodiment, for example, noise of about 1V can be removed. In this differential transmission method, for example, the signal voltage change is only about several hundred mV. Therefore, as advantages other than those described above, high-speed data throughput, reduced power consumption, noise reduction, low cost, and high integration can be expected.

  As described above, in the configuration of the first embodiment, the low voltage differential transmission line connectors for connecting the apparatus main body and the carriage (recording head) are provided in the vicinity of the transmitter and the receiver. At this time, the pair wirings of the low-voltage differential transmission line are arranged close to each other, and the power supply line is separated from the pair wiring. According to this configuration, it is possible to cancel the noise jumping into the transmission line and prevent the occurrence of abnormality in the data transmitted to the recording head. As a result, resistance to noise can be improved, and a highly reliable recording apparatus that is not easily affected by radiation noise or external noise can be realized.

  In addition, since differential transmission at a low voltage is used, the transmission speed is increased as compared with the prior art, and a large amount of data can be transmitted. Further, the radiation noise is reduced despite the high speed data transmission. In addition, the device cost can be reduced by high integration.

  Note that the feature of low noise on the LVDS line has the advantage of being strong against external noise interference. This means that it is resistant to interference such as induction radiation noise of an electric motor and dive noise from a nearby transmission line. Therefore, it is resistant to fluctuations in the power source and can be said to be an optimum configuration in the recording apparatus.

(Embodiment 2)
Next, Embodiment 2 will be described. FIG. 7 is a diagram schematically showing a control communication system in the control circuit 10 and the carriage-side control circuit 20 according to the second embodiment.

  Here, a rectangular frame indicated by a dotted line in the drawing is a flexible cable (FPC) for connecting the recording apparatus main body and the carriage. As shown in FIG. 4, the configuration of the second embodiment is a mode in which a control signal from the control circuit 10 is directly supplied to the recording head IJH.

  That is, as can be seen by comparing FIG. 6 describing the first embodiment and FIG. 7 showing the configuration of the second embodiment, the LVDS receiver 21 is provided in the carriage-side control circuit 20 in the configuration of the first embodiment. On the other hand, in the configuration of the second embodiment, the LVDS receiver 21 of the LVDS line is arranged in the recording head IJH. The configuration shown in FIG. 7 is suitable when the recording head IJL has an area where the LVDS receiver 21 can be mounted. For example, it is suitable when the shape of the recording head IJH is relatively long.

  Since the recording head IJH to the recording head substrate 103 are often connected via wire bonding or inner leads, the LVDS receiver 21 is arranged near the end of the same line. The connection between the flexible cable and the recording head IJH may be realized by, for example, a general-purpose connector or a card edge connector.

  As an example of a modification of the second embodiment, an LVDS receiver 21 of an LVDS line may be incorporated on the recording head substrate 103 as shown in FIG.

  FIG. 8 is a diagram illustrating a modified example according to the second embodiment. The configuration shown in FIG. 8 is a configuration in which the LVDS receiver 21 of the LVDS line is incorporated on the recording head substrate 103 together with the drive circuit while adopting the configuration of the control communication system similar to the configuration shown in FIG.

  As described above, according to the second embodiment, the LVDS receiver is provided on the recording head or the recording head substrate in the recording head. In this case, the same effect as that of the first embodiment can be obtained. When the LVDS receiver 21 is disposed on the recording head substrate 103, the recording head substrate may temporarily hold a large amount of data transmitted at high speed and perform data expansion. it can.

  In recent years, the print head board is often built on the same board, including a shift register, a latch circuit, an AND circuit, a decoder circuit, etc., and a print element and a drive circuit. It is not necessary to have a drive circuit for the recording element. For this reason, according to the configuration of the second embodiment, the cost of the recording apparatus can be reduced, and even when the number of recording elements increases, it is not necessary to increase the number of connection terminals to the recording elements.

(Embodiment 3)
Next, Embodiment 3 will be described. FIG. 9 is a diagram schematically showing a control communication system in the control circuit 10 and the carriage-side control circuit 20 according to the third embodiment.

  In the third embodiment, a case will be described in which communication is performed using a packet-configured communication protocol in order to increase the speed and capacity of communication between the apparatus main body and the print head IJH. In this case, drive control is performed by generating a waveform from data without using a pulse width signal.

  In order to realize this configuration, a communication protocol is defined between the recording apparatus and the recording head IJH, and recording data and driving signals are transferred using the same transmission line. The control circuit 10 of the recording apparatus includes a recording data control unit 13 that develops recording data and the like, and a drive control unit 12 that generates data based on a drive signal (hereinafter referred to as data related to drive control). Further, the control circuit 10 is provided with a packet transmission control unit 15 as a first transmission control means for packetizing and transmitting various information to the recording head IJH side. Note that data transmission by the packet transmission control unit 15 is performed based on a predetermined communication protocol. The packet transmission control unit 15 packetizes the recording data developed by the recording data control unit 13 and the data related to the drive control generated by the drive control unit 12. Then, the packetized data is transmitted to the recording head IJH side while arbitrating the transmission processing of various data. The packet transmission control unit 15 converts recording data and data related to drive control into data in a format according to a communication protocol, and assembles a packet. Then, the packet is transmitted to the LVDS line.

  On the other hand, the carriage-side control circuit 20 is provided with a packet transmission control unit 22 as second transmission control means. The packet transmission control unit 22 arbitrates various data sent from the apparatus main body side, and restores the data sent from the packet transmission control unit 15 into recording data and data related to drive control. That is, the packet transmission control unit 22 disassembles a packet having a format according to the communication protocol, and reconstructs recording data and data related to drive control. As a result, in the recording head IJH, the driving process similar to that in the first and second embodiments described above is performed. Note that the packet transmission control unit 22 described above may be provided not on the carriage-side control circuit 20 but on the printhead IJH or the printhead substrate 103 as in the second embodiment.

  FIG. 10 is a diagram illustrating a modified example according to the third embodiment. The configuration shown in FIG. 10 adopts the same control communication system configuration as the configuration shown in FIG. 9, and the LVDS receiver 21 and the packet transmission control unit 22 of the LVDS line are incorporated on the recording head substrate 103 together with the drive circuit. It has a configuration.

  As described above, according to the third embodiment, the apparatus main body and the recording head are realized by packet transmission using a communication protocol. In this case, in addition to the same effects as those of the first embodiment, data transmission generated between the two can be realized by one transmission line.

  In addition, it is expected that the recording head will be further enhanced in the future, such as providing the packet transmission control unit 22 and performing packet transmission with the apparatus main body. When the packet transmission control unit 22 is incorporated in the recording head substrate 103, the recording apparatus main body and the recording head are high-function devices on a dedicated transmission line. In such a configuration, as described above, data communication between the recording head and the recording apparatus is realized with the minimum number of lines, and signal lines other than the power supply and the LVDS line are not necessary. Thereby, the cost of an apparatus can be suppressed further.

  The above is an example of a typical embodiment of the present invention, but the present invention is not limited to the embodiment described above and shown in the drawings, and can be appropriately modified and implemented without departing from the scope of the present invention. .

  Needless to say, high-speed and large-capacity data transfer using a low-voltage differential transmission line does not depend on the electrical, mechanical configuration, software sequence, etc. of the printing apparatus body, carriage-side control circuit, and printing head. Absent.

1 is a diagram illustrating an example of an external configuration of a recording apparatus according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an example of an internal configuration of the recording apparatus illustrated in FIG. 1. It is a figure which shows an example of a structure of a transmission line. It is a figure which shows an example of a structure of a transmission line. 2 is a diagram illustrating an example of a configuration of a control circuit 10 and a carriage side control circuit 20 according to the first embodiment. FIG. 2 is a diagram schematically showing a control communication system in a control circuit 10 and a carriage side control circuit 20 according to the first embodiment. FIG. 6 is a diagram schematically showing a control communication system in a control circuit 10 and a carriage side control circuit 20 according to Embodiment 2. FIG. FIG. 10 is a diagram illustrating a modification example according to the second embodiment. FIG. 10 is a diagram schematically showing a control communication system in a control circuit 10 and a carriage side control circuit 20 according to a third embodiment. FIG. 10 is a diagram showing a modification example according to the third embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Control circuit 11 Power supply part 12 Drive control part 13 Recording data control part 14 LVDS transmitter 15, 22 Packet transmission control part 20 Carriage side control circuit 21 LVDS receiver 103 Recording head board 131 Memory 1700 Interface 1701 MPU
1702 ROM
1703 DRAM
1704 Gate array (GA)
1706, 1707 Motor driver 1709 Conveyance motor 5013 Carriage motor HC Carriage IJH Recording head

Claims (21)

A control circuit provided in the apparatus body;
A carriage on which a recording head having a plurality of recording elements is mounted;
A flexible cable having a plurality of signal lines for connecting the control circuit and the carriage and transmitting various signals;
The plurality of signal lines are:
Including a power supply line for supplying power used to drive the recording element and a low voltage differential transmission line composed of a pair wiring for performing transmission by a low voltage differential transmission system,
The control circuit includes:
A control circuit side connector for connecting the low voltage differential transmission line;
A transmitter that is provided in the vicinity of the control circuit side connector and transmits a signal via the control circuit side connector and the low voltage differential transmission line;
The carriage is
A carriage side connector for connecting the low-voltage differential transmission line;
A receiver that is provided in the vicinity of the carriage-side connector and receives a signal sent from the transmitter via the carriage-side connector and the low-voltage differential transmission line;
In the flexible cable,
The recording apparatus, wherein the pair wirings of the low-voltage differential transmission line are arranged close to each other, and the power supply line is arranged separately from the pair wiring. The carriage is
A carriage side control circuit including a logic circuit for controlling the recording head,
The receiver is
The recording apparatus according to claim 1, wherein a signal received from the transmitter is amplified to an amplitude of a drive voltage of the carriage-side control circuit. The flexible cable is
It consists of a planar shape, a plurality of signal lines are arranged along a predetermined direction of the same planar shape,
The pair wiring of the low voltage differential transmission line is:
The recording apparatus according to claim 1, wherein the recording apparatus is disposed at a position other than the end portion of the plurality of signal lines disposed along the predetermined direction of the same plane. The carriage is
A carriage side control circuit including a logic circuit for controlling the recording head,
The receiver is
The recording apparatus according to claim 1, wherein the recording apparatus is disposed in the carriage-side control circuit. The control circuit includes:
First transmission control means for packetizing information including a recording signal and a driving signal transmitted by the transmitter toward the carriage;
The carriage is
Further comprising second transmission control means for restoring the information packetized by the first transmission control means to information before being packetized;
The transmission between the control circuit and the carriage via the low-voltage differential transmission line is performed by packet transmission according to a predetermined communication protocol. The recording device described. In the plurality of signal lines,
The recording apparatus according to claim 1, further comprising: a recording signal, a clock signal for transmitting the recording signal, and a signal line for transmitting a latch signal for latching the recording signal. In the low voltage differential transmission line,
The recording apparatus according to claim 1, further comprising: a signal line for transmitting a recording signal and a clock signal for transmitting the recording signal. The recording element is:
The recording apparatus according to claim 1, comprising: an electrothermal conversion element that generates thermal energy applied to the ink in order to eject the ink using thermal energy. Said separation is
The recording apparatus according to claim 1, wherein the recording apparatus uses a ground terminal wiring. Recording connected to the recording apparatus by a flexible cable having a signal line including a power supply line for supplying power used for driving the recording element and a low-voltage differential transmission line composed of a pair wiring that performs transmission by a low-voltage differential transmission system Head,
A connector for connecting the low-voltage differential transmission line;
A receiver that is provided in the vicinity of the connector and receives a signal sent from the recording device via the connector and the low-voltage differential transmission line;
In the flexible cable,
The recording head, wherein the pair wirings of the low-voltage differential transmission line are arranged close to each other, and the power supply line is arranged separately from the pair wiring. Transmission control means for restoring packetized information to information before being packetized,
The receiver is
Receiving information in which a recording signal and a driving signal are packetized from the recording device via the low-voltage differential transmission line;
The transmission control means includes
The recording head according to claim 10, wherein the packetized information received by the receiver is restored to information before being packetized. In the signal line,
The recording head according to claim 10, further comprising: a recording signal, a clock signal for transmitting the recording signal, and a signal line for transmitting a latch signal for latching the recording signal. In the low voltage differential transmission line,
The recording head according to claim 10, further comprising: a signal line for transmitting a recording signal and a clock signal for transmitting the recording signal. The recording element is:
The recording head according to claim 10, comprising an electrothermal conversion element that generates thermal energy to be applied to the ink in order to eject the ink using thermal energy. Said separation is
The recording head according to claim 10, wherein the recording head is performed using a ground terminal wiring. Recording connected to the recording apparatus by a flexible cable having a signal line including a power supply line for supplying power used for driving the recording element and a low-voltage differential transmission line composed of a pair wiring that performs transmission by a low-voltage differential transmission system A head substrate of the head,
A connector for connecting the low-voltage differential transmission line;
A receiver that is provided in the vicinity of the connector and receives a signal sent from the recording device via the connector and the low-voltage differential transmission line;
In the flexible cable,
The head substrate, wherein the pair wirings of the low-voltage differential transmission line are arranged close to each other, and the power supply line is arranged separately from the pair wiring. Transmission control means for restoring packetized information to information before being packetized,
The receiver is
Receiving information in which a recording signal and a driving signal are packetized from the recording device via the low-voltage differential transmission line;
The transmission control means includes
The head substrate according to claim 12, wherein the packetized information received by the receiver is restored to information before being packetized. In the signal line,
The head substrate according to claim 12, further comprising: a recording signal, a clock signal for transmitting the recording signal, and a signal line for transmitting a latch signal for latching the recording signal. In the low voltage differential transmission line,
The head substrate according to claim 12, further comprising a signal line for transmitting a recording signal and a clock signal for transmitting the recording signal. The recording element is:
The head substrate according to claim 12, comprising an electrothermal conversion element that generates thermal energy applied to the ink in order to eject the ink using thermal energy. Said separation is
The head substrate according to claim 12, wherein the head substrate is formed using a ground terminal wiring.

Images