External wireless transmitter, sensor device and sensor system

Abstract

[Problem] The present invention provides an external wireless transmitter that can easily set a sensor device to be wireless at low cost without undergoing large-scale changing or modification. [Solution] A wireless transmitter 10 that is externally fitted to an output terminal 101 of a sensor device 100 and that wirelessly transmits a sensor output signal comprises: a fitting part 12 that is fitted to a draw-in inlet 103 which is for fitting an output cable 104 and which is provided to the output terminal 101; an input conducting wire 14 that is electrically connected to a terminal 110 which is provided to the output terminal 101 and to which the output cable 104 is connected; and a wireless transmission unit 16 that wirelessly transmits the sensor output signal inputted through the input conducting wire 14.

Description

External wireless transmitter, sensor device and sensor system

[0001] The present invention relates to a wireless sensor device.

[0002] In conventional sensor devices used in harsh environments, an output cable is connected to a terminal in a strong, waterproof, and dustproof terminal box, and an output signal of the sensor device is transmitted to the outside via a wired connection. In recent years, efforts have been made to improve productivity (reducing wiring costs, etc.) and safety (avoiding wired disconnections) by using wireless sensor devices that utilize ICT technologies such as IoT (see, for example, Patent Documents 1 and 2).

[0003] However, these wireless sensor devices are provided as products equipped with a wireless transmitter from the beginning, so users of conventional wired sensor devices must make a large investment to replace their wired sensor devices with wireless sensor devices. Furthermore, the wireless functionality must be verified after the device is installed on-site. In other words, depending on the installation location, the wireless functionality may not function satisfactorily. In this case, the wired sensor device must be reinstalled, resulting in significant effort and unnecessary expense.

[0004] Another option is to convert a wired sensor device to a wireless one, rather than replacing it with a wireless one. However, this conversion is costly, and even if converted to a wireless system, there are cases where the wireless function cannot be used depending on the installation location and other environments, as mentioned above, and converting the system back to a wired system is also costly. As such, converting a sensor device to a wireless system requires effort and cost, making it difficult to simply make the investment.

[0005] JP 2013-120582 A JP 2013-504207 A

[0006] In light of this current situation, the present invention aims to provide a technology that enables users who are currently using conventional wired sensor devices to easily and at low cost convert their sensor devices to wireless, thereby enabling them to more actively promote wirelessization, which increases productivity and safety, by reducing wiring costs and avoiding wire breaks.

[0007] In view of the current situation, the inventors conducted extensive research and discovered that if it were possible to use the output cable inlet and output terminal section of existing wired sensor devices as they are and attach an external wireless transmitter instead of the output cable, it would be possible to easily and at low cost make a sensor device wireless, without having to prepare a new wireless sensor device or modify it to be wireless, and this led to the completion of the present invention.

[0008] In other words, the present invention provides an external wireless transmitter that is attached externally to the output terminal section of a sensor device and wirelessly transmits a sensor output signal, and that includes: an attachment section that is attached to an output cable attachment port provided on the output terminal section; an input conductor that is electrically connected to a terminal section provided on the output terminal section to which the electrical wire of the output cable is connected; and a wireless transmitting section that wirelessly transmits the sensor output signal input through the input conductor.

[0009] With this type of external wireless transmitter, a sensor device can be easily and inexpensively made wireless by simply attaching the external wireless transmitter to the inlet or output terminal of an existing wired sensor device instead of an output cable, without requiring major changes or modifications. Furthermore, simply removing the external wireless transmitter makes it easy to return the sensor device to a wired system using an output cable instead, allowing a data transmission method to be selected according to the facility environment without incurring additional costs or effort.

[0010] It is also preferable that the wireless transmitter be provided with a battery for supplying power thereto.

[0011] This eliminates the need for wiring for external power supply, making it possible to more reliably reduce wiring costs.

[0012] It is also preferable that the attachment portion has a female thread portion or a male thread portion that screws into a male thread portion or a female thread portion formed in the inlet.

[0013] This configuration allows the external wireless transmitter to be easily attached and detached.

[0014] Preferably, the wireless transmission unit includes an analog-to-digital conversion circuit that converts the sensor output signal, which is an analog signal, into a digital signal.

[0015] Preferably, the wireless transmitter includes a wireless transmitter circuit for wirelessly transmitting the sensor output signal.

[0016] Furthermore, it is preferable that the external wireless transmitter has a waterproof and dustproof structure.

[0017] The present invention also provides a sensor device comprising an output terminal section and an external wireless transmitter attached to the output terminal section for wirelessly transmitting a sensor output signal, wherein the wireless transmitter has an attachment section that is attached to an output cable attachment port provided in the output terminal section, an input conductor that is provided inside the output terminal section and electrically connected to a terminal section to which the electrical wire of the output cable is connected, and a wireless transmitter section that wirelessly transmits the sensor output signal input through the input conductor.

[0018] With such a sensor device, by providing an external wireless transmitter that is attached to the output terminal section, it can be used as a wired sensor device using an output cable, or as a wireless sensor device by attaching an external wireless transmitter instead of the output cable, allowing the data transmission method to be selected according to the facility environment without incurring additional costs or effort.

[0019] The present invention also provides a sensor system comprising a sensor device having an output terminal section and an external wireless transmitter attached to the output terminal section and wirelessly transmitting a sensor output signal, and a wireless receiving device that receives the sensor output signal from the external wireless transmitter, wherein the external wireless transmitter of the sensor device has an attachment section that is attached to an output cable attachment inlet provided in the output terminal section of the sensor device, an input conductor that is provided inside the output terminal section and electrically connected to a terminal section to which the electrical wire of the output cable is connected, and a wireless transmitting section that wirelessly transmits the sensor output signal input through the input conductor.

[0020] With such a sensor system, by providing an external wireless transmitter that is also attached externally to the output terminal section, it is possible to use the system as a wired sensor device using an output cable, or to attach an external wireless transmitter instead of the output cable and use the system as a wireless sensor device, thereby allowing the selection of a data transmission method that suits the facility environment without incurring additional costs or effort.

[0021] For use in explosion-hazardous areas, it is preferable to obtain explosion-proof certification and use it as an external wireless device that can be attached and detached as an intrinsically safe, explosion-proof wireless sensor for wireless process communication.

[0022] Without major changes or modifications, a sensor device can be made wireless easily and at low cost by simply attaching an external wireless transmitter instead of an output cable to the inlet or output terminal of a wired sensor device. Furthermore, simply removing the external wireless transmitter makes it easy to revert to a wired sensor device that uses an output cable instead, allowing you to select a data transmission method that suits your facility environment without incurring additional costs or effort.

[0023] Fig. 1 is a front view showing a wireless sensor device to which an external wireless transmitter is externally attached according to an embodiment of the present invention. Fig. 2 is an explanatory diagram showing that an output cable and an external wireless transmitter are interchangeable. Fig. 3 is a front view showing a sensor device according to another embodiment of the present invention. Fig. 4 is a block diagram showing a sensor system according to an embodiment of the present invention using the sensor device shown in Fig. 1. Fig. 5 is a front view illustrating a wired sensor device using an output cable.

[0024] Next, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

[0025] As shown in FIG. 1 , the sensor device 100 includes a measuring unit 102 and an output terminal unit 101 provided on the base end side of the measuring unit 102. The output terminal unit 101 includes an inlet 103 for drawing an output cable into the housing of the output terminal unit 101, and a terminal unit 110 to which the input end of the output cable is connected. The measuring unit 102 is an instrument that measures pressure, flow rate, temperature, etc., and the measurement target is not particularly limited. Here, a temperature sensor is used as an example of a field device. A compensation lead wire (not shown) is connected to the base end of the temperature sensor, which is the measuring unit 102, and the compensation lead wire is electrically connected to the terminal unit 110.

[0026] When the sensor device 100 transmits a sensor output signal to the outside via a wired system, the attachment part 105 of the output cable 104 is attached to the inlet 103, as shown in Fig. 5. The input end 106 of the output cable 104 is drawn in from the attachment part 105 attached to the inlet 103 and connected to the terminal part 110 by a conductor, and the other end is connected to an external device (not shown). The external device is, for example, a device that stores, calculates, and displays the sensor output signal from the measuring part 102.

[0027] As shown in FIG. 1, the external wireless transmitter 10 according to the present invention can be attached externally to the sensor device 100 in place of the output cable 104, and wirelessly transmits the sensor output signal from the sensor device 100 to an external device.

[0028] The external wireless transmitter 10 comprises an attachment part 12 attached to the inlet 103 of the output terminal part 101, an input lead 14 electrically connected to a terminal part 110 of the output terminal part 101, and a wireless transmitter part 16 that wirelessly transmits a sensor output signal input through the input lead 14. The attachment part 12 preferably has the same structure as the attachment part 105, and if the attachment part 105 has a male thread, the attachment part 12 also has a male thread, and the attachment part 12 can be screwed into a female thread formed on the inlet 103 through which the output cable 104 was led, thereby allowing the external wireless transmitter 10 to be easily attached to and detached from the inlet 103.

[0029] This allows the output cable 104 to be replaced with the external wireless transmitter 10, or the external wireless transmitter 10 to be removed and replaced with the output cable 104, without requiring major work such as changing or modifying the equipment, as shown in FIG. 2.

[0030] The mounting portion 12 may have a female thread and the inlet 103 may have a male thread. Of course, the mounting portion 12 and the inlet 103 may be connected using a structure other than a screw structure. A connector, adapter, or the like may be interposed between the mounting portion 12 and the inlet 103 to attach the mounting portion 12 to the inlet 103. It is preferable to tightly join the mounting portion 12 and the inlet 103 to create a waterproof and dustproof structure.

[0031] The input lead wire 14 is electrically connected to a terminal portion 110 provided on the output terminal portion 101. The electrically connected input lead wire 14 inputs the sensor output signal from the measuring portion 102 to the wireless transmitting portion 16.

[0032] The wireless transmitter 16 wirelessly transmits the sensor output signal input through the input conductor 14. The wireless transmitter 16 is configured with, for example, an analog-to-digital conversion circuit 161 that converts the analog sensor output signal into a digital signal, and a wireless transmitter circuit 162 that wirelessly transmits the digital signal. The wireless transmitter 16 also includes a central processing unit (CPU) that controls the circuits that make up the wireless transmitter 16, a random access memory (RAM) that temporarily stores data, and a non-volatile storage device such as a hard disk drive (HDD) or a solid state drive (SSD).

[0033] The wireless transmitter 16 may use various wireless communication methods, such as wireless communication circuits using electromagnetic waves, such as Bluetooth (registered trademark), Wi-Fi (registered trademark), ZigBee (registered trademark), or NFC (Near Field Communication), or infrared communication or visible light communication.

[0034] The external wireless transmitter 10 includes a battery 18 that supplies power to the wireless transmitting unit 16. As a result, the external wireless transmitter 10 is powered by the battery 18, eliminating the need for wiring to draw power from the outside, thereby enabling a more reliable reduction in wiring costs.

[0035] The battery 18 may be, for example, a storage battery that can store electricity, and may be connected to a power generation means such as a solar panel. As a result, the power generated by the power generation means is stored in the battery 18, and the necessary power is supplied from the battery 18 to the wireless transmission unit 16.

[0036] The sensor device 100 according to the present invention may have two or more inlets 103. Figure 3 shows a sensor device 100' according to another embodiment of the present invention, which has two inlets 103.

[0037] The sensor device 100' has a housing for the output terminal section 101 provided with a first inlet 103' for attaching the attachment section 105 of the wired output cable 104 and leading in the input end 106, and a second inlet 103'' for attaching the attachment section 12 of the external wireless transmitter 10 according to the present invention and leading in the input wire 14. The input end 106 and the input wire 14 are both electrically connected to the terminal section 110.

[0038] This allows the sensor output signal to be transmitted to an external device via either or both of the output cable 104 and the external wireless transmitter 10 .

[0039] If a malfunction occurs in either the output cable 104 or the wireless transmitter 10, a sensor output signal can be transmitted to an external device via the other of the output cable 104 and the wireless transmitter 10. At the same time, it is also possible to notify the external device that a malfunction has occurred in either the output cable 104 or the wireless transmitter 10. In other embodiments, a plurality of sensor devices can be provided and connected to each other by a wired method such as the output cable 104 or wirelessly by the external wireless transmitter 10 according to the present invention, and a sensor output signal can be transmitted wirelessly to an external device from one of the sensor devices provided with the external wireless transmitter 10 according to the present invention.

[0040] Referring to FIG. 4, a sensor system 1 according to the present invention includes a sensor device 100 having an external wireless transmitter 10 and a wireless receiving device 90 for receiving a sensor output signal from the external wireless transmitter 10 .

[0041] The wireless receiving device 90 uses the same wireless communication method as the wireless transmitting unit 16 to receive the sensor output signal from the wireless transmitter 10. The wireless receiving device 90 can be incorporated into an external device that requires the sensor output signal from the sensor device 100, or can be provided separately from the external device. The structure of the wireless receiving device 90 is well known, so a description thereof will be omitted.

[0042] In the sensor system 1 according to the present invention, a sensor output signal, which is the result of measurement by a measurement unit 102 included in a sensor device 100, is input to an external wireless transmitter 10 externally attached to an output terminal unit 101 of the sensor device 100, and the sensor output signal is wirelessly transmitted from the external wireless transmitter 10. The wirelessly transmitted sensor output signal is received by a wireless receiving device 90.

[0043] The measuring unit 102 measures the temperature inside the kneader, which is the measurement target, using, for example, a temperature sensor provided inside the kneader, and outputs a sensor output signal as the result.

[0044] The sensor output signal output from the measuring unit 102 is input to the wireless transmitting unit 16 provided in the external wireless transmitter 10 via the input lead 14 .

[0045] The wireless transmitting unit 16 converts the sensor output signal input from the input conductor 14 into a form that can be transmitted wirelessly, and wirelessly transmits the sensor output signal to the wireless receiving device 90. For example, as shown in Fig. 4, an analog-to-digital conversion circuit 161 constituting the wireless transmitting unit 16 converts the analog sensor output signal into a digital signal, and a wireless transmitting circuit 162 wirelessly transmits the digitally converted sensor output signal to the wireless receiver 90.

[0046] The external wireless transmitter 10 is also provided with an external connection unit 17 that can be connected to an external terminal (not shown). The external connection unit 17 is connected to the external terminal via a wired connection such as a USB (Universal Serial Bus) terminal, or wirelessly via a connection such as Bluetooth (registered trademark). The external terminal is a terminal such as a personal computer or tablet that checks the communication status with the wireless receiving device 90, investigates the cause of a communication problem, and configures the external wireless transmitter 10 itself. By providing the external connection unit 17 in the external wireless transmitter 10, the sensor system 1 allows not only inspection and communication-related operations to be performed on the wireless receiving device 90 side, but also inspection and communication-related operations to be performed on the external wireless transmitter 10 side. Needless to say, in the sensor system 1, the external connection unit 17 may temporarily output a sensor output signal input from the sensor device 100 to the external terminal due to a communication inspection, a communication problem, or the like. It is assumed that the connection with the external terminal by the external connection unit 17 does not interfere with the transmission of the sensor output signal by the wireless transmission unit 16 .

[0047] The wireless receiving device 90 can receive the sensor output signal and input it to an external device. If the external device is, for example, a display, information such as the temperature measured based on the sensor output signal, the remaining charge of the battery 18, and an alarm when a predetermined threshold is exceeded can be displayed on the display.

[0048] As a modified example, the sensor system 1 according to the present invention can transmit the sensor output signal from the external wireless transmitter 10 to the wireless receiving device 90 in a relay manner via multiple wireless relay devices 91, as shown in FIG.

[0049] The sensor system 1 can extend the transmission distance of the sensor output signal and avoid existing facilities that may interfere with wireless transmission by interposing a wireless relay device 91 between the external wireless transmitter 10 and the wireless receiving device 90. The structure of the wireless relay device 91 is also well known, so a description thereof will be omitted.

[0050] Therefore, the sensor system 1 of the present invention can transmit the sensor output signal from the measurement unit 102 of the sensor device 100 to an external device wirelessly, without any major changes or modifications, simply by externally attaching the external wireless transmitter 10 to the output terminal unit 101 of the sensor device 100.

[0051] Furthermore, in the sensor system 1 according to the present invention, if the external wireless transmitter 10 is removed from the output terminal unit 101 and an output cable 104 is used instead, the sensor device 100 can transmit measurement data in a wired manner. This allows a data transmission method to be selected according to the installation environment without incurring additional costs or effort.

[0052] Although the embodiments of the present invention have been described above, the present invention is not limited to these examples, and it goes without saying that the present invention can be embodied in various forms without departing from the spirit of the present invention.

[0053] REFERENCE SIGNS LIST 1 sensor system 10 external wireless transmitter 12 mounting portion 14 input lead 16 wireless transmission portion 17 external connection portion 18 battery 90 wireless receiving device 91 wireless relay device 100 sensor device 100' sensor device 101 output terminal portion 102 measuring portion 103 inlet 103' first inlet 103'' second inlet 104 output cable 105 mounting portion 106 input terminal 110 terminal portion 161 analog-to-digital conversion circuit 162 wireless transmission circuit

Claims

1. A wireless transmitter that is attached externally to the output terminal section of a sensor device and transmits a sensor output signal wirelessly, comprising: an attachment section that is attached to an inlet for attaching an output cable provided on the output terminal section; an input conductor that is electrically connected to a terminal section provided on the output terminal section to which the electrical wire of the output cable is connected; a wireless transmission section that wirelessly transmits the sensor output signal input through the input conductor; and a battery that supplies power to the wireless transmission section.

2. An external wireless transmitter according to claim 1, wherein said mounting portion has a female or male screw portion that screws into a male or female screw portion formed in said inlet.

3. The external wireless transmitter according to claim 1, wherein said wireless transmission section includes an analog-to-digital conversion circuit for converting an analog sensor output signal into a digital signal.

4. The external wireless transmitter according to claim 1, wherein said wireless transmitting section includes a wireless transmitting circuit for wirelessly transmitting a sensor output signal.

5. The external wireless transmitter according to claim 1, which has a waterproof and dustproof structure.

6. A sensor device comprising an output terminal section and an external wireless transmitter attached to the output terminal section for wirelessly transmitting a sensor output signal, wherein the external wireless transmitter has: an attachment section that is attached to an outlet for attaching an output cable provided in the output terminal section; an input wire that is provided inside the output terminal section and electrically connected to a terminal section to which the electrical wire of the output cable is connected; a wireless transmission section that wirelessly transmits the sensor output signal input through the input wire; and a battery that supplies power to the wireless transmission section.

7. The sensor device according to claim 6, wherein the mounting portion of the external wireless transmitter has a female or male screw portion that screws into a male or female screw portion formed in the inlet.

8. A sensor system comprising a sensor device having an output terminal section and an external wireless transmitter attached to the output terminal section for wirelessly transmitting a sensor output signal, and a wireless receiving device for receiving the sensor output signal from the external wireless transmitter, wherein the external wireless transmitter of the sensor device has: an attachment section that is attached to an outlet for attaching an output cable provided in the output terminal section of the sensor device; an input conductor that is provided inside the output terminal section and electrically connected to a terminal section to which the electrical wire of the output cable is connected; a wireless transmitting section that wirelessly transmits the sensor output signal input through the input conductor; and a battery that supplies power to the wireless transmitting section.

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