Pressure

Abstract

To provide a pressure gauge which is easy to handle, compact, and suitable for remote pressure monitoring. [Solution] The pressure gauge 1 comprises a rotating shaft 2 that is supported for free rotation, a shaft rotation mechanism 3 that applies a rotational force to the middle of the rotating shaft 2 to rotate the rotating shaft 2 by an angle corresponding to the pressure to be measured, a pressure display unit 6 that displays the measured value of the pressure using a pointer 4 and a scale plate 5 that are fixed to one end of the rotating shaft 2 and rotate in conjunction with the rotating shaft 2, and a magnet 7 that is fixed to the other end of the rotating shaft 2 and rotate in conjunction with the rotating shaft 2.

Description

[Technical field]

[0001] The present invention relates to a pressure gauge having a magnet fixed to a shaft of a pointer and rotating in conjunction with the shaft. [Background technology]

[0002] Conventionally, there has been known a pressure display device that indicates the pressure inside a compressed gas container using a pointer that oscillates along a scale plate, and that can also display the pressure on a display instrument positioned a predetermined distance away from the instrument (see, for example, Patent Document 1).

[0003] In the device of the patent, a permanent magnet is attached to the pointer of the pressure gauge to provide a pressure indication on a display instrument separate from the gauge, and a magnetic Hall effect sensor is arranged to provide an electrical signal proportional to the change in magnetic field at a fixed point as a function of the amount of movement of the pointer. The output signal of this sensor is amplified by an amplifier and sent to a display instrument. The display instrument provides an indication of the pressure based on the amplified signal. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 57-212600 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the pressure display device of the above-mentioned Patent Document 1, the magnetic Hall effect sensor is placed at a fixed point at a fixed distance from the permanent magnet. This fixed point is a point where the magnetic field lines from the permanent magnet are as straight as possible. Therefore, the distance from the permanent magnet to the magnetic Hall effect sensor is relatively large, and the size of the display device including the magnetic Hall effect sensor is accordingly large.

[0006] In addition, because the magnetic Hall effect sensor, the pointer, the permanent magnet, and the power supply are all located within the same instrument, maintenance work is complicated, for example, when replacing the battery, as this requires disassembling the instrument. Even if it is sufficient to display the pressure measurement value with only the pointer, the magnetic Hall effect sensor and its power supply are always integrated within the instrument, which can result in excessive functionality.

[0007] Furthermore, remote monitoring devices that can be selectively attached to single-function pressure gauges and that convert pressure into electricity and transmit it are also commercially available, but their installation poses the problem of requiring the pressure gauge to be disassembled.

[0008] In view of the problems with the conventional technology, an object of the present invention is to provide a pressure gauge that is easy to handle, compact, convenient, and also suitable for remote pressure monitoring. [Means for solving the problem]

[0009] The pressure gauge of the present invention comprises: A rotating shaft supported so as to be freely rotatable; a shaft rotation mechanism that applies a rotational force to an intermediate portion of the rotating shaft to rotate the rotating shaft by an angle corresponding to the pressure to be measured; a pressure display unit that displays the pressure measurement value using a pointer and a scale plate that are fixed to one end of the rotary shaft and rotate in conjunction with the rotary shaft; a magnet fixed to the other end of the rotating shaft and rotating in conjunction with the rotating shaft. In the pressure gauge, a sensor that detects a magnetic field that changes due to the rotation of the magnet linked to the rotating shaft while being attached to the pressure gauge, and outputs a signal corresponding to the pressure; A signal transmission unit having a transmission means for transmitting an output signal of the sensor to a monitoring location for monitoring the pressure is detachable. It is characterized by: Effect of the Invention

[0010] According to the present invention, since the magnet that rotates in conjunction with the pointer is provided on the end of the rotating shaft opposite to the pointer, a signal corresponding to the measured pressure value can be obtained by attaching a sensor that detects changes in the magnetic field of the magnet to the back side of the pressure gauge. By sending this signal to a remote monitoring location away from the pressure gauge by a signal transmission unit, pressure can be monitored even remotely.

[0011] Furthermore, when remote pressure monitoring is not required, the pressure gauge can be used alone without attaching the sensor or signal transmission unit. In this case, maintenance work such as replacing the battery or secondary battery that supplies power to the sensor and signal transmission unit can be performed with these removed from the pressure gauge, greatly improving convenience. Therefore, according to the present invention, it is possible to provide a pressure gauge that is easy to handle, compact, convenient, and also suitable for remote pressure monitoring.

[0012] Furthermore, in the case of a sealed pressure gauge in which vibrations and pulsations are absorbed by filling the pressure gauge with glycerin, disassembly is difficult, and the present invention, which makes it possible to separate the sensor and signal transmission section, is particularly effective for such a glycerin-based pressure gauge. [Brief description of the drawings]

[0013] [Figure 1] 1 is a side view showing a simplified configuration of a pressure gauge and a signal transmission unit according to an embodiment of the present invention. FIG. [Diagram 2] 2 is a diagram showing a shaft rotation mechanism that rotates the rotation shaft of the pressure gauge in FIG. 1. [Diagram 3] 2 is a cross-sectional view showing the configuration of the pressure gauge and the signal transmission unit of FIG. 1. [Figure 4] FIG. 2 is an exploded perspective view showing the configuration of the pressure gauge and the signal transmission unit of FIG. [Diagram 5] 4 is a perspective view showing the structure of a magnet held by a magnet spacer in the pressure gauge of FIG. 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 shows a simplified pressure gauge and signal transmission unit according to one embodiment of the present invention. As shown in Fig. 1, this pressure gauge 1 includes a rotating shaft 2 supported so as to be freely rotatable, a shaft rotation mechanism 3 that applies a rotational force to an intermediate portion of the rotating shaft 2 to rotate the rotating shaft 2 by an angle corresponding to the pressure to be measured, and a pressure display unit 6 that displays the measured pressure value using a pointer 4 and a scale plate 5 that are fixed to one end of the rotating shaft 2 and rotate in conjunction with the rotating shaft 2.

[0015] Furthermore, pressure gauge 1 is equipped with magnet 7 that is fixed to the other end of rotating shaft 2 and rotates in conjunction with rotating shaft 2. Pressure gauge 1 having the above configuration is housed in housing 8. The front surface of housing 8 is made of glass plate 9 so that pointer 4 and scale plate 5 can be visually observed.

[0016] A signal transmission unit 10 that transmits a signal corresponding to a measurement value by the pressure gauge 1 to a monitoring position is detachably attached to the housing 8 of the pressure gauge 1. The signal transmission unit 10 is configured to be detachably attached to the back surface of the housing 8 of the pressure gauge 1 when stored in the signal transmission unit storage case 11.

[0017] The signal transmission unit 10 includes a sensor 12 that detects a magnetic field that changes with the rotation of the magnet 7 linked to the rotating shaft 2 while attached to the housing 8 of the pressure gauge 1, and outputs a signal corresponding to the pressure being measured, and a transmission means 13 that transmits the output signal of the sensor 12 to a monitoring position where the pressure is monitored. The sensor 12 used here is one that uses a magnetoresistance element (MR sensor).

[0018] Fig. 2 shows a specific configuration of the pressure transmission mechanism 14 as viewed from the rear side of the scale plate 5. As shown in Fig. 2, the pressure transmission mechanism 14 includes an introduction part 15 for introducing the pressure to be measured, a Bourdon tube 16 that is connected to the introduction part 15 and deforms in response to changes in the pressure, and the above-mentioned shaft rotation mechanism 3 that rotates the rotation shaft 2 of the pointer 4 in response to the deformation of the Bourdon tube 16. Note that the magnet 7 is not shown in Fig. 2.

[0019] 3 and 4 are a cross-sectional view and an exploded perspective view specifically showing the configuration of the pressure gauge 1 in FIG. 1 and the signal transmission unit 10 detachably attached thereto. As shown in FIG. 3 and FIG. 4, the magnet 7 in the pressure gauge 1 is fixed to the rotating shaft 2 via a magnet spacer 17. On the inside of the back plate that closes the back side of the housing 8 of the pressure gauge 1, a magnetic plate 19 is provided for detachably attaching the transmission unit storage case 11 that houses the signal transmission unit 10 to the housing 8 of the pressure gauge 1.

[0020] The transmission unit storage case 11 is composed of a substrate fixing case 20 to which the signal transmission unit 10 is fixed inside, and a case cover 21 that covers the substrate fixing case 20. The transmission unit storage case 11 is attached to the pressure gauge 1 via the outer surface of the substrate fixing case 20.

[0021] A mounting magnet 22 capable of being attracted to the magnetic plate 19 is provided on the outer surface of the substrate fixing case 20 at a position corresponding to the magnetic plate 19 of the pressure gauge 1. That is, the transmission unit storage case 11 is detachable from the housing 8 of the pressure gauge 1 by the magnetic plate 19 and the mounting magnet 22. Therefore, the signal transmission unit 10 is attached to the pressure gauge 1 by attaching the transmission unit storage case 11 to the housing 8.

[0022] In this embodiment, a magnet is used as an example of a method of attachment and detachment, but this is not limited to magnets. It is also possible to use screws or a screw-type housing, or a removable silicone adhesive.

[0023] The signal transmission unit 10 includes the above-mentioned sensor 12 that detects a magnetic field that changes due to the rotation of the magnet 7 linked to the rotating shaft 2 and outputs a signal corresponding to the pressure to be measured when the signal transmission unit 10 is attached to the pressure gauge 1, and the above-mentioned transmission means 13 that transmits the output signal of the sensor 12 to a monitoring position where the pressure is monitored. As the transmission means 13, Wi-Fi, Bluetooth (trademark), or other wireless communication means or wired communication means can be used.

[0024] The electric transmission means 13 includes a circuit board 23 fixed to the board fixing case 20, a wireless communication board 24 provided on the circuit board 23, a battery holder 25 fixed to the circuit board 23, a battery 26 attached to the circuit board 23 via the battery holder 25, and an antenna sheet 27 provided on the battery 26. Power is supplied from the battery 26 to the sensor 12 and the wireless communication board 24 via a power connector 28.

[0025] The sensor 12 is provided at a position where it faces the magnet 7 and can properly detect changes in the magnetic field caused by the magnet 7 when the signal transmission unit 10 is attached to the pressure gauge 1. That is, the sensor 12 is provided at the center of a circuit board 23 fixed inside a board fixing case 20. The power to the sensor 12 and the power transmission unit 13 is turned on and off by a power switch 29. The on and off state of the power is monitored by a power LED 30.

[0026] FIG. 5 shows magnet 7 held by magnet spacer 17. As shown in FIG. 5, the center line extending between the south pole S and north pole N of magnet 7 is located on the central axis of the rotating shaft or its extension line L. Desirably, as shown in FIG. 5, the magnet 7 is a cylindrical one made of a cylindrical ferromagnetic metal material magnetized in the radial direction (the direction of the arrow in the figure) so that one anti-cylindrical part becomes the north pole N and the other anti-cylindrical part becomes the south pole S. Then, magnet 7 is arranged so that the center line of the cylindrical shape coincides with the central axis of rotating shaft 2 or its extension line L.

[0027] In this configuration, when pressure from a pipe for water, gas, compressed air, etc. is introduced into the introduction part 15 of the pressure gauge 1, the Bourdon tube 16 is deformed. The shaft rotation mechanism 3 rotates the rotating shaft 2 according to the amount of this deformation. The pointer 4 rotates in conjunction with this rotation and indicates the scale on the scale plate 5, so the measured pressure value can be known by reading the indicated scale.

[0028] At this time, when the signal transmission unit 10 is attached to the pressure gauge 1 by the attraction between the mounting magnet 22 of the transmission unit storage case 11 and the magnetic plate 19 of the housing 8 of the pressure gauge 1, the magnetic field of the magnet 7 that rotates in conjunction with the rotation of the rotating shaft 2 fluctuates according to the amount of rotation. This magnetic field fluctuation is detected by the sensor 12, and the detection signal is transmitted by the transmission means 13 to a monitoring position (display instrument) that monitors the pressure.

[0029] This detection signal has a signal value corresponding to the measurement value by the pressure gauge 1. Therefore, the monitoring position can receive the transmitted detection signal and display a value equivalent to the measurement value by the pressure gauge 1 based on the signal value.

[0030] As described above, according to this embodiment, the magnet 7 which rotates in conjunction with the pointer 4 is provided at the end of the rotating shaft 2 opposite the pointer 4, so that the change in the magnetic field caused by the rotation of the magnet 7 can be easily detected by the sensor 12 from the back side of the pressure gauge 1.

[0031] Therefore, by attaching an electric transmission unit storage case 11 having a sensor 12 and an electric transmission means 13 to the housing 8 of the pressure gauge 1, a detection signal value equivalent to the measurement value by the pressure gauge 1 can be transmitted to a remote location, and the measurement value can be monitored at the remote location to monitor pressure fluctuations.

[0032] Furthermore, when remote monitoring is not required, the pressure gauge 1 can be used as an easy-to-handle, compact normal pressure gauge by removing the transmission unit storage case 11 from the pressure gauge 1. In this case, maintenance such as replacement of the battery 26 that supplies power to the sensor 12 and the transmission means 13 can be performed with the transmission unit storage case 11 removed from the housing 8 of the pressure gauge 1, improving convenience.

[0033] Furthermore, since the center line extending between the south pole S and north pole N of the magnet 7 is located on the central axis of the rotating shaft 2 or its extension line L, strong magnetic field lines from the south pole S to the north pole N are present near the end of the magnet 7 on the sensor 12 side. Therefore, the change in the magnetic field lines caused by the magnet 7 can be detected with high accuracy by the sensor 12. Therefore, the pressure gauge 1 and the signal transmission unit 10 can be configured compactly.

[0034] Although the embodiment of the present invention has been described above, the present invention is not limited to this. For example, a sensor using a Hall element may be used as the sensor 12. [Explanation of symbols]

[0035] 1...pressure gauge, 2...rotating shaft, 3...axis rotation mechanism, 4...pointer, 5...scale plate, 6...pressure display unit, 7, 7a, 7b...magnets, 8...casing, 9...glass plate, 10...signal transmission unit, 11...transmission unit storage case, 12...sensor, 13...transmission means, 14...pressure transmission mechanism, 15...introduction unit, 16...Bourdon tube, 17...magnetic spacer, 19...magnetic plate, 20...board fixing case, 21...case cover, 22...mounting magnet, 23...circuit board, 24...wireless communication board, 25...battery holder, 26...battery, 27...antenna sheet, 28...power connector, 29...power switch, 30...power LED, L...central axis or its extension, N...north pole, S...south pole.

Claims

1. A rotating shaft supported so as to be freely rotatable; a shaft rotation mechanism that applies a rotational force to an intermediate portion of the rotating shaft to rotate the rotating shaft by an angle corresponding to the pressure to be measured; a pressure display unit that displays the pressure measurement value using a pointer and a scale plate that are fixed to one end of the rotary shaft and rotate in conjunction with the rotary shaft; a magnet fixed to the other end of the rotating shaft and rotating in conjunction with the rotating shaft, a sensor that detects a magnetic field that changes due to the rotation of the magnet linked to the rotating shaft while being attached to the pressure gauge, and outputs a signal corresponding to the pressure; A pressure gauge comprising a detachable signal transmission unit and a transmission means for transmitting an output signal of the sensor to a monitoring location for monitoring the pressure.

2. 2. The pressure gauge according to claim 1, wherein the center line of the magnet extending between its south pole side portion and its north pole side portion is located on the central axis of the rotating shaft or an extension thereof.

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