JP2016046791A - Transmission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent reception of second data from being erroneously recognized by receiving noise that is generated when an MCU is operated, by a second antenna, in a transmission device formed by proximately disposing a plurality of transmitters in the same configuration in a fixed three-dimensional array, each transmitter being formed by accommodating an electronic circuit including the MCU, a first antenna for transmitting first data generated by the transmitter to the outside by radio and a second antenna for receiving the second data for adjusting timing among each transmitter to transmit the first data from the first antenna by radio from the outside by radio within at least a predetermined housing.SOLUTION: In the vicinity of an arrangement position of the electronic circuit including the MCU in a housing 130 of each transmitter, a conductor plate 500 that is electrically insulated is provided, thereby blocking the noise that is generated when the MCU is operated.SELECTED DRAWING: Figure 10

Description

  The present invention relates to a noise blocking technique in a transmission apparatus in which a plurality of transmitters having the same configuration including a microcomputer unit are arranged in close proximity in a fixed three-dimensional array.

  Conventionally, compressed water is sealed in a substantially bowl-shaped hollow structure made of an elastic material such as rubber for the purpose of preventing damage to the hull or quay when the ship berths on the quay in the harbor or between the ships. One or more fenders were interposed between the quay and the ship or between the ships. In addition, since the above-described fender must always maintain an appropriate air pressure, a transmission device capable of detecting at least the air pressure and transmitting the detected value to the outside by radio waves is provided in the fender. The air pressure of the fender is managed from a remote location through a receiving device capable of receiving the radio wave (see Patent Document 1).

  By the way, in order to monitor and display the amount of shaking of the hull in real time from the above-described detected air pressure value, it is necessary to update the detected value at intervals of 2 seconds or less. There is a restriction that radio waves must be transmitted at predetermined intervals (for example, 10 seconds or more if the carrier frequency is 315 MHz).

  In view of this, a device (hereinafter also referred to as “transmitting device”) in which a plurality of transmitters in which the above-described transmitting devices are unitized is provided in the fender, and the transmission timing of radio waves in each transmitter is shifted from each other. Thus, a proposal has been made that the detection value can be updated at an interval shorter than the predetermined pause time (see Patent Document 2).

  FIG. 1 shows an example of the above-described transmission apparatus. Here, eight unitized transmitters 100 (100a to 100h) are housed in a case 11 made of an insulator that transmits radio waves and are placed in a fender. Installed.

  Each transmitter 100 (100a to 100h) has the same configuration, and as shown in FIGS. 2 to 4, the transmitter main body 300 is housed in a substantially rectangular parallelepiped casing 130 made of an insulator that transmits radio waves. Configured.

  As shown in FIGS. 2 to 4, the casing 130 of the transmitter 100 has a substantially rectangular parallelepiped shape, has protrusions for screwing at both ends in the longitudinal direction, the casing main body 131 and the lid 132. It consists of and. As shown in FIGS. 3 and 4, a housing space 134 for housing the transmitter main body 300 is formed inside the housing body 131, and the opening of the housing space 134 screws the lid 132 to the housing body 131. It is closed by fixing with 141. In addition, a vent hole 133 is formed in the lid body 132, and even when the lid body 132 is fixed to the housing body 131, air can flow from the outside to the storage space 134 through the vent hole 133. ing.

  As shown in FIG. 5 to FIG. 7, the transmitter main body 300 includes two printed wiring boards 351 and 352 having a substantially rectangular shape arranged in parallel at a predetermined interval, and an RF antenna 450 is formed between them. The columnar connection conductors 354 and the third printed wiring board 353 for connection are fixed to each other. A coiled RF antenna (first antenna) 450 having a central axis extending in the width direction of the first and second printed wiring boards 351 and 351 is formed at the other end of the transmitter body 300 in the longitudinal direction. On one end side, electronic components constituting an electronic circuit including a sensor unit 410 and a battery 420 are mounted. The connecting printed wiring board 353 is soldered to each of the two printed wiring boards 351 and 352, and a sheet coil-like HF antenna (second antenna) (not shown) is formed on the surface thereof.

  The first printed wiring board 351 and the second printed wiring board 352 are provided between them, and fix the other printed wiring board to the one printed wiring board at a predetermined interval, and The printed wiring and the printed wiring of the other printed wiring board are connected by a plurality of columnar connecting conductors 354 that are conductively connected.

  The transmitter body 300 is formed with an electronic circuit 400 shown in FIG. That is, the electronic circuit 400 includes a pressure sensor 410, a battery 420, an MCU 430, a transmission / reception circuit 440, an RF antenna 450, and an HF antenna 460.

  The pressure sensor 410 is mounted on the surface of the main body 300, detects the air pressure of the fender (in the air chamber), converts this detection result into analog / digital and outputs it to the MCU 430. The battery 420 is connected to the transmitter main body 300 by a connection conductor and supplies power to the electronic circuit 400 formed in the transmitter main body 300. Needless to say, not only the pressure sensor but also a sensor capable of detecting various physical states, such as a temperature sensor and a humidity sensor, may be provided to output these data.

  The MCU 430 is a one-chip microcomputer unit, and unique identification information different for each of the transmitters 100a to 100h is written in advance in the memory together with a predetermined operation program. The MCU 430 receives the detection result by the pressure sensor 410 as a digital value, generates first data including the digital value, and outputs the first data to the transmission / reception circuit 440. The MCU 430 includes second data for adjusting the timing of wireless transmission of the first data included in the HF band radio wave transmitted from an external wireless facility (not shown) between the transmitters 100a to 100h. Specifically, every eight intervals 100a to 100h of radio transmission timing are evenly shifted, for example, if one transmitter has a radio transmission timing every 10 seconds, the transmission is shifted by 1.25 seconds. Second data for adjustment so as to be every interval is received from the transmission / reception circuit 440.

  In addition to the digital value of the detection result, the first data includes identification information unique to each transmitter 100a to 100h, for example, a serial number, and the second data also includes the transmitters 100a to 100h. The identification information is included together with information representing each timing.

  The transmission / reception circuit 440 transmits the first data input from the MCU 430 from the RF antenna 450 using an RF band carrier frequency, for example, a radio wave of 315 MHz, and receives the HF band carrier frequency received by the HF antenna 460, for example, Demodulate the 13.56 MHz radio wave and output the second data to the MCU 430.

  The RF antenna 450 is a coiled antenna whose resonance frequency is set to the carrier frequency of the RF band, and the printed wiring 351a provided on the first printed wiring board 351 and the printed wiring board 352 provided on the second printed wiring board 352. The wirings 352a and the printed wirings of the first printed wiring board 351 and the printed wirings of the second printed wiring board 352 are conductively connected and formed by columnar connecting conductors 354 that fix the printed wiring boards 351 and 352 to each other.

  Further, a rectangular planar conductor plate 361 is fixed to the outer surface of the other end of the first printed wiring board 351 by four holding members 371. A planar conductor plate 361 is provided at the position of the RF antenna 450 so as to be parallel to the printed wiring board 351 located on the bottom surface side of the casing body 131 when the transmitter body 300 is housed in the casing 130. The flat conductor plate 361 is fixed to the first printed wiring board 351 by a holding material 371 so as to maintain a predetermined distance. The planar conductor plate 361 is conductively connected to a predetermined conductor pattern (a conductor pattern connected to the negative electrode of the battery 420) of the first printed wiring board 351 and set to a reference potential. The resonance frequency of the RF antenna 450 is 315 MHz in the state where the planar conductor plate 361 is mounted on the printed wiring board 351.

  The HF antenna 460 is a sheet coil antenna whose resonance frequency is set to the carrier frequency of the HF band, and is formed by a printed wiring (not shown) provided on the third printed wiring board 353. .

  The transmitters 100 (100a to 100h) described above are housed in the case 11 and installed in the fender as shown in FIG. 1. At this time, the transmitters 100 (100a to 100h) are close to each other in order to be housed in the minimum space. When arranged, the transmitters may interfere with each other, and the gain of the transmission radio wave may decrease. For this reason, the transmitters 100 (100a to 100h) are arranged close to each other in a certain three-dimensional arrangement as shown in FIG. 9, that is, an arrangement in which the electronic circuits of the two transmitters face each other, thereby reducing the gain. (See Patent Documents 3 and 4).

  However, in the transmission apparatus described above, noise in the HF band, here 13.56 MHz band received by the HF antenna 460 during operation of the MCU 430 is generated, and a transmitter adjacent to the noise includes the second data described above. There has been a problem that erroneous operation that erroneously receives radio waves and frequently repeats RF transmission occurs, which hinders accurate management of air pressure, and causes a decrease in remaining battery capacity due to an increase in power consumption.

In the present invention, in order to solve the above problem,
A transmitter in which a plurality of transmitters having the same configuration are arranged close to each other in a fixed three-dimensional array. Each transmitter transmits an electronic circuit including an MCU and first data generated by the transmitter to the outside. A first antenna for wireless transmission and a second antenna for wirelessly receiving second data for adjusting the timing of wireless transmission of the first data from the first antenna between the transmitters In a transmission device in which an antenna is housed in at least a predetermined housing,
An electrically insulated conductor plate is provided in the vicinity of the arrangement position of the electronic circuit including the MCU in the casing of each transmitter.

  According to the present invention, the HF band noise generated from the MCU is blocked by the electrically insulated conductor plate provided in the vicinity of the arrangement position of the electronic circuit including the MCU, and this noise is transmitted to the adjacent transmitter. Is not erroneously received as a radio wave including the second data, and a malfunction that repeats RF transmission does not occur.

Configuration diagram showing an example of a conventional transmitter External perspective view of a conventional transmitter Plan view of a conventional transmitter Side cross-sectional view of a conventional transmitter External perspective view of a conventional transmitter body External perspective view of a conventional transmitter body External perspective view of the main part of a conventional transmitter body The block diagram which shows the electric system circuit of the conventional transmitter Schematic which shows an example of arrangement | positioning of the transmitter in the conventional transmitter. 1 is an external perspective view of a transmitter showing an example of an embodiment of the present invention. Side surface sectional drawing of the transmitter which shows an example of embodiment of this invention

  10 and 11 show an example of the embodiment of the present invention. In the vicinity of the arrangement position of the electronic circuit including the MCU 430 of the casing 130 of each transmitter 100 (100a to 100h), here, the casing body. A conductive plate 500 such as an aluminum foil in an electrically insulated state was provided at a position facing the MCU 430 inside the bottom surface of 131.

  In addition to the aluminum foil, the conductor plate 500 may be a copper foil, an iron plate, or the like. Also, the conductor plate 500 may be attached by using an adhesive, screwing, vacuum deposition, or the like. You can also.

  At this time, the size of the conductor plate 500 is set to be larger than the projected area of the MCU 430 in order to sufficiently block noise from the MCU 430. In addition, the thickness also reduces the influence of the radio wave transmitted from the RF antenna 450 on the carrier frequency of the radio wave transmitted by the RF antenna 450 (the carrier frequency is 315 MHz and the conductor plate 500 is made of copper foil). In this case, it is set to 3.7 μm) or more.

  As a result, the HF band noise generated during the operation of the MCU 430 is cut off, so that an adjacent transmitter does not receive this noise erroneously as a radio wave including the second data, and a malfunction that repeats RF transmission does not occur. . Specifically, there were 23 malfunctions per minute in the absence of the conductor plate 500, but there were 0 malfunctions after the conductor plate 500 was attached.

  Note that the above-described noise can be blocked by attaching a sheet metal covering the MCU 430 to the first printed wiring board 351 on which an electronic circuit including the MCU 430 is mounted. There is a problem that a space for attaching the sheet metal is required and the cost is high.

  The present invention can be used in a system that detects and monitors various physical states including a pneumatic fender and the air pressure of the fender.

  100 (100a to 100h): transmitter, 130: housing, 131: housing body, 132: lid body, 133: vent hole, 134: storage space, 141: screw, 300: transmitter body, 351: first Printed wiring board, 351a: Printed wiring, 352: Second printed wiring board, 352a: Printed wiring, 353: Third printed wiring board, 354: Columnar connecting conductor, 361: Planar conductor plate, 371: Holding material, 400: Electronics Circuit: 410: Pressure sensor, 420: Battery, 430: MCU, 440: Transmission / reception circuit, 450: RF antenna, 460: HF antenna, 500: Conductor plate.

Japanese Patent Application Laid-Open No. 60-046438 JP 2010-175298 A JP 2012-080484 A JP 2012-105061 A

Claims (4)

A transmitter in which a plurality of transmitters having the same configuration are arranged close to each other in a fixed three-dimensional array. Each transmitter transmits an electronic circuit including an MCU and first data generated by the transmitter to the outside. A first antenna for wireless transmission and a second antenna for wirelessly receiving second data for adjusting the timing of wireless transmission of the first data from the first antenna between the transmitters In a transmission device in which an antenna is housed in at least a predetermined housing,
A transmission apparatus comprising a conductive plate in an electrically insulated state in the vicinity of an arrangement position of an electronic circuit including the MCU in a casing of each transmitter. The transmitter according to claim 1, wherein each transmitter is arranged so that electronic circuits of two or more transmitters face each other. The transmitting apparatus according to claim 1, wherein the size of the conductor plate is equal to or larger than a projected area of the MCU. The transmitter according to claim 1, wherein the thickness of the conductor plate is set to be equal to or greater than a skin depth with respect to a radio carrier frequency transmitted by the first antenna.

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