JP3172814U - Small data collection device - Google Patents

Abstract

Provided is a small data collection device that can be installed even in a limited narrow space and can record analog data in an ultrasonic region while performing high-speed FFT processing.
A small data collection device 10 receives an input unit that receives a signal from a sensor 21 that measures vibration and ultrasonic waves, a trigger circuit 14 that receives a trigger input, and a universal serial bus (USB) driver. It has an interface unit that can communicate with an external device, a power source unit, and a signal processor (DSP) 13 that controls them. The interface unit is connected to the USB memory 16 in order to store the measurement data obtained by the A / D converter 12 and can communicate with the personal computer (PC) 22 via the USB driver 15 by specific low power radio. It is connected to the radio device 17.
[Selection] Figure 1

Description

  The present invention relates to a small data collection apparatus that can be installed in a limited narrow space and collects and records ultrasonic band data.

  A conventional small data acquisition apparatus is known that supports analog inputs that change relatively slowly. For example, Patent Document 1 discloses a small data collection device that is configured such that a plurality of analog sensors can be connected to a single small data collection device, and can measure and collect a plurality of different analog quantities.

  This small data collection device does not require any other power supply and can be installed in a limited space. For example, it can be installed inside an electronic control device of an air conditioner. This small data collection device can measure a plurality of analog quantities at the same time, and configure and collect a plurality of detected analog data as a set of data. Like data, it can be converted into a single data and stored.

JP-A-8-159817

  The small data collection device described in Patent Document 1 can input analog data that is relatively slow in change or digital data such as a switch. For example, it occurs at the tip of a marine propeller underwater. It has been difficult to record cavitation noise, ultrasonic waves generated by a fish finder, and acoustic data such as acoustic noise, which is an ultrasonic wave generated when a bat crys or an object is damaged in the air. This is because the sampling frequency is as high as several hundred kHz, and it is necessary to adjust the bandpass characteristics of the input filter amplifier, and CPU processing capability capable of executing high-speed FFT processing is required. Further, in the case of measuring cavitation noise of a rotating marine propeller, it is necessary to attach a slip ring to the propeller shaft and to extract a signal through the slip ring, and the experimental apparatus has been enlarged.

  Therefore, the small data collection device according to the present invention provides a small data collection device that can be installed even in a limited narrow space and can record analog data in the ultrasonic region while performing high-speed FFT processing. Objective.

  In order to achieve the above object, a small data collection device according to the present invention is a small data collection device that can be attached to an object to be measured, and a filter amplifier that receives a signal from a sensor, and a signal from the filter amplifier A / D converter for converting ultrasonic frequency band, signal processor for processing data from A / D converter, serial interface circuit for communicating with signal processor, and memory connected to serial interface circuit And a board for electrically connecting these electronic components.

  Further, in the small data collection device according to the present invention, a trigger circuit that inputs start or stop of data collection to the signal processor by an external trigger, a specific low-power radio device connected to the serial interface circuit, and a chargeable second And a power source capable of charging the secondary battery via a power source coil by electromagnetic induction.

  In the small data collection device according to the present invention, the substrate is a business card size. By adopting such a shape, it can be easily installed inside the device.

  In the small data collection device according to the present invention, the serial interface circuit is a universal serial bus (USB). By using USB connection, a plurality of ports can be provided, and a USB memory, a specific low-power radio device, or the like can be connected.

  In the small data collection device according to the present invention, the substrate is formed of a flexible substrate and can be stored in a rectangular or cylindrical case. By adopting such a configuration, it is possible to install in a more limited space by folding the substrate.

  By using the small data collection device according to the present invention, a small data collection device of a business card size can be arranged inside the control device to collect necessary data. Also, a small data collection device composed of a flexible board is accommodated by folding so that it can be accommodated in a ship propeller shaft, and the wiring in the propeller shaft is used without using a slip ring to measure the cavitation noise of the propeller. Only by this, the experimental apparatus can be downsized.

It is a block diagram which shows the structure of the small data collection device which concerns on embodiment of this invention. It is explanatory drawing explaining an example of the mounting state of the board | substrate and component which comprise the small data collection device which concerns on embodiment of this invention. It is explanatory drawing explaining an example of the mounting state of the small data collection device using the flexible substrate which concerns on other embodiment of this invention. It is explanatory drawing explaining an example of the state which folded the small data collection device shown in FIG. It is explanatory drawing explaining the experimental apparatus for accommodating the small data collection device shown in FIG. 4 in the ship propeller shaft, and measuring the cavitation noise of the ship propeller.

  Hereinafter, the best mode for carrying out the present invention (hereinafter referred to as an embodiment) will be described with reference to the drawings.

  FIG. 1 shows the configuration of a small data collection device 10. The small data collection device 10 includes an input unit that receives a signal from a sensor 21 that measures vibration and ultrasonic waves, a trigger circuit 14 that receives a trigger input, and an external device via a universal serial bus (USB: registered trademark) driver. It has an interface unit that can communicate with the device, a power source unit, and a signal processor (DSP) 13 that controls them. The input unit can accept a signal in accordance with the ultrasonic characteristics of the sensor, and a band pass filter (BPF) 11 having a function of a filter amplifier, and an A / D converter 12 capable of A / D conversion at a sampling frequency of 192 kHz. And have. The trigger unit has a trigger circuit and a trigger out 33 for outputting a trigger signal. The trigger circuit 14 accepts a measurement start signal, thereby enabling data collection in an event-based measurement event. The interface unit is connected to the USB memory 16 in order to store the measurement data obtained by the A / D converter 12 and can communicate with the personal computer (PC) 22 via the USB driver 15 by specific low power radio. It is connected to the radio device 17. The power supply unit includes a power supply 18 connected to a battery 19 that supplies a voltage of 5 V, and a power supply coil 23 for charging the battery 19. The external power supply 24 having the power supply coil 23 and electromagnetic induction Can be electrically connected.

  The DSP 11 is connected to the PC 22 through a serial interface such as RS-232C, and can not only perform setting information and measurement of the small data collection device 10 but also transmit measured data to the PC 21 through the serial interface. The DS 11 can wirelessly communicate with the PC 22 via the wireless device 17 connected to the USB driver 15. Further, the DSP 11 has a built-in timer, and can start / end measurement at a predetermined time or transmit measurement data to the PC 21 at a predetermined time. Furthermore, the DSP 11 can perform control from the PC 22 by wireless communication and can eliminate the extra wiring by charging the battery 19 by electromagnetic induction, thereby preventing an increase in the size of the experimental apparatus. .

  FIG. 2 shows an example of the mounting state of the board and components that constitute the small data collection device 10. The small data collection device 10 has the configuration shown in FIG. 1 on a business card size substrate 25, and the back surface of the substrate 25 is covered with an insulating film. One of the characteristic features of the present invention is that the sampling frequency can be set to 32 kHz, 48 kHz, 96 kHz, and 192 kHz in order to enable data collection in the ultrasonic band. With this sampling frequency, it is possible to measure at a maximum recording frequency of 96 kHz at a frequency after anti-aliasing processing by a bandpass filter.

  The small data collection device 10 uses an 8 Gbyte USB memory, and enables continuous data collection for about 32 hours at a sampling frequency of 32 kHz. In order to enable such long-time measurement, the power saving design is such that the current consumption of the small data collection device 10 is 50 mA during standby, 150 mA during standby in the trigger mode, and 200 mA during memory recording. The battery 19 of FIG. 2 realizes an operation of about 90 hours by using a lithium ion battery with a supply voltage of 5 V and about 18000 mAh. Further, in order to secure a dynamic range in data collection, the set noise is suppressed to about −100 db. Since the small data collection device 10 in FIG. 2 has a trigger input, as a normal measurement mode, in addition to free-run measurement and timer measurement, it is synchronized with event-based measurement and other small data collection devices. It is also possible to carry out measurements.

  FIG. 3 shows an example of a mounting state of the small data collection device 20 using the flexible substrate 26, and FIG. 4 shows a state where the small data collection device shown in FIG. 3 is folded. Although it is relatively easy to arrange the business card size small data collection device 20 in the control device, the electronic component is arranged on the flexible substrate 26 and folded in order to be able to be installed in a further narrow space. I was able to do that. Further, in consideration of insertion / removal of the USB memory 16, the end of the flexible substrate 26 is fixed with an adhesive tape 36, the strap 34 is provided on the small data collection device 20, and the USB memory 16 is arranged in the longitudinal direction. Even after the small data collection device 20 is installed in a limited cylindrical space, the USB memory can be easily replaced. Note that the back surface of the flexible substrate 26 is covered with an insulating film.

  FIG. 5 shows an experimental apparatus for measuring the cavitation noise of the marine propeller 31 by accommodating the small data collection device 20 shown in FIG. 4 in the marine propeller shaft 32. In the propeller shaft 32, two small data collection devices 20 and one battery 19 are installed, and a cable from the sensor 21 attached to the marine propeller 31 is connected to each small data collection device 20. . In addition, two small data collection devices 20 are connected by a trigger line 35 in order to measure in synchronization.

  The small-sized data collection device 20 can measure cavitation noise generated at the tip of the propeller by disposing the marine propeller 31 in water and rotating the propeller shaft 32 with a motor (not shown). Measurement control is performed by wireless communication from the PC 21, and measurement data measured by each small data collection device 20 is received by the PC 21 by wireless communication. Further, since the battery 19 can be charged using the external power source 24 via the power supply coil attached to the small data collection device 20, it is possible to save the trouble of removing the small data collection device 20 for charging. Can do.

  As described above, by using the small data collection device according to the present embodiment, the business card size small data collection device can be arranged inside the control device, and necessary data can be collected. It can be used as a data logger. In addition, a small-sized data collection device composed of a flexible substrate is accommodated by being folded so that it can be accommodated in a propeller shaft for a ship, and a propeller is used without using a connecting device such as a slip ring to measure cavitation noise of the propeller. Only the wiring in the shaft is required, and the enlargement of the experimental apparatus can be prevented.

  10, 20 Small data collection device, 11 BPF, 12 A / D converter, 14 Trigger circuit, 15 USB driver, 16 USB memory, 17 Radio, 18 Power supply, 19 Battery, 21 Sensor, 23 Power supply coil, 24 External Power supply, 25 substrate, 26 flexible substrate, 31 marine propeller, 32 marine propeller shaft, 33 trigger out, 34 strap, 35 trigger line, 36 adhesive tape.

Claims (5)

In a small data collection device that can be attached to a device under test,
A filter amplifier that accepts the signal from the sensor;
An A / D converter in an ultrasonic frequency band for converting a signal from the filter amplifier;
A signal processor for processing data from the A / D converter;
A serial interface circuit for communicating with the signal processor;
A memory connected to a serial interface circuit;
A board for electrically connecting these electronic components;
A small-sized data collection device characterized by comprising: The small data collection device according to claim 1,
A trigger circuit for inputting start or stop of data collection to the signal processor by an external trigger;
A specific low power radio connected to the serial interface circuit;
Rechargeable secondary battery,
A power supply capable of charging a secondary battery via a power supply coil by electromagnetic induction;
A small-sized data collection device characterized by comprising: In the small data collection device according to claim 1 or 2,
A small-sized data collection device, wherein the substrate is a business card size. In the small data collection device according to claim 1 or 2,
A small-sized data collection device, wherein the serial interface circuit is a universal serial bus (USB). The small data collection device according to claim 1,
A small-sized data collection device, wherein the substrate is formed of a flexible substrate and can be stored in a rectangular or cylindrical case.

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