JP2006234626A - Hydrogen flame ionization gas detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydrogen flame ionization gas detector, capable of preventing the gas detector from being tipped over unexpectedly, when the gas detector is laid on a floor face, capable of managing thereby the gas detector with high safety, and capable of stably maintaining functions inherent to the gas detector. <P>SOLUTION: This hydrogen flame ionization gas detector is provided with a box-like thin outer shell as the whole thereof, is constituted to arrange in the outer shell a hydrogen flame ionization sensor, a hydrogen gas cylinder, an electric power source for battery and circuit board, and is constituted to be portable. In the gas detector, the center of gravity position as the whole of the gas detector exists within the upper half area, and a contact face to the floor face in the gas detector is formed into a self-standing disabled condition. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a flame ionization type gas detector.

Conventionally, for example, as a method for detecting the concentration of hydrocarbon gas, for example, gas molecules of hydrocarbon gas are ionized in a hydrogen flame to detect ionic current, and the concentration of hydrocarbon gas is determined based on the detection result. A detection method is used.
As a hydrogen flame ionization type gas detector using such a detection method, those having various configurations have been proposed (for example, refer to Patent Document 1). For example, from a conduit and a supply pipe embedded in the ground. In the gas leak inspection and the like, a portable type is used.
JP 2000-227416 A

  And in the portable hydrogen flame ionization type gas detector, when it is equipped with a thin box-shaped outer casing, for example, when the gas detector is placed on the floor surface in a standing state, There is a risk that the gas detector may fall down unexpectedly, and there is a risk of causing a failure, leakage of hydrogen gas, fire, and explosion due to an impact caused by the fall of the gas detector.

  The present invention has been made based on the above circumstances, and the gas detector is placed on the floor surface so that the gas detector does not fall down unexpectedly. It is an object of the present invention to provide a flame ionization type gas detector that can manage the gas detector with high safety and can stably maintain the original function of the gas detector.

The hydrogen flame ionization gas detector of the present invention comprises a thin box-shaped outer casing as a whole, and a hydrogen flame ionization sensor, a hydrogen gas cylinder, a battery power supply unit and a circuit board are arranged in the outer casing. It is a portable type,
The center of gravity of the entire gas detector is present in the upper half region of the outer casing, and the floor-to-floor contact surface of the gas detector is formed in a state where it cannot stand by itself.

  According to the hydrogen flame ionization gas detector of the present invention, the center of gravity of the entire gas detector exists in the upper half area, and the outer surface of the outer casing facing the floor surface is in a state incapable of self-supporting. Therefore, if left unattended, it cannot stand on its own due to the action of gravity and falls down on its own, so that it is placed on the floor and does not fall down unexpectedly, and no impact is applied. Therefore, the gas detector can be managed with high safety and the original function of the gas detector can be stably maintained.

  In addition, since the outer casing is formed in a thin box shape, it is configured to be easily carried by the detector. Therefore, it is practically an obstacle to perform the intended work during gas measurement. In addition, high convenience can be obtained.

  Furthermore, the state where the center of gravity exists in the upper half region of the gas detector is achieved by collecting and arranging the main components such as the battery and the flame ionization type sensor, so the flame ionization type Maintenance of the sensor or the like can be improved.

  Hereinafter, the present invention will be described with reference to the drawings.

FIG. 1 is a front view showing an external appearance of a gas detector main body in a configuration example of a hydrogen flame ionization gas detector according to the present invention, FIG. 2 is a top view of the gas detector main body shown in FIG. 1 is a left side view of the gas detector main body shown in FIG. 1, FIG. 4 is a right side view of the gas detector main body shown in FIG. 1, and FIG. 5 is a schematic diagram of the internal structure of the gas detector main body shown in FIG. It is explanatory drawing shown. Hereinafter, the direction defined in this specification is based on a state when a standing person carries the gas detector body 10 on the back.
A gas detector main body 10 includes a thin box-shaped outer casing 11 that can be carried on the back of a person. Side walls 13A and 13B made of a plate-like elastic cover with a metal plate embedded therein are provided.
A display unit 18 and an operation unit 19 are provided at an upper part of the front surface of the outer casing 11.

Each side wall 13A, 13B is formed with a tongue piece 14 projecting inward in the lateral direction facing the side edge of the upper surface plate of the outer casing 11 at the upper end portion. It is attached to the outer casing 11 by being locked to the upper surface of the side edge portion of the upper surface plate.
Each of the side walls 13A, 13B has a bottom leg 15 projecting downward from the bottom plate of the outer casing 11, and the lower end surface of the bottom leg 15 is a floor-to-floor contact surface 15A.
The floor-to-floor contact surface 15A has a shape in which the gas detector body 10 cannot stand by itself, specifically, for example, a shape that is curved in an arc shape in the front-rear direction so as to protrude downward.

  In the upper part of the outer casing 11, a battery chamber 12 is formed in which two rod-shaped rechargeable batteries 20 are arranged side by side so as to extend in the vertical direction. A control unit 55 including a signal processing circuit board and a power supply circuit board, and a hydrogen flame ionization sensor unit (hereinafter referred to as “sensor unit”) 50 are disposed on the right side in FIG. On the other side (left side in FIG. 5), a gas cylinder loading chamber 17 in which a hydrogen gas cylinder for supplying hydrogen gas as combustion gas to the sensor unit 50 is loaded is formed.

A flow rate adjusting valve 30 and a sample gas suction pump 32 for adjusting the supply amount of hydrogen gas are arranged in a lower part inside the outer casing 11.
The flow rate adjusting valve 30 is connected to the gas cylinder main body 42 via a hydrogen gas supply pipe 31 </ b> A extending in the vertical direction in parallel with the gas cylinder main body 42 in the hydrogen gas cylinder, and extends laterally outward toward the side wall of the outer casing 11. The sensor unit 50 is connected to the sensor unit 50 via a hydrogen gas supply pipe 31B extending upward from a lower position of the sensor unit 50.
The sample gas suction pump 32 is connected to a sample gas introduction connector portion 34 provided on one side of the gas detector body 10 and is connected to the sensor portion 50 via a sample gas supply pipe 33.
The gas detector body 10 has a structure in which hydrogen gas, which is a combustion gas, and sample gas (measurement gas) are supplied to the sensor unit 50 in a separated state.

  In the gas detector main body 10, the center of gravity of the gas detector main body 10 in a state in which the hydrogen gas cylinder is loaded in the gas cylinder loading chamber 17 is in a state where it exists in the upper half region of the outer casing 11. . Specifically, in this embodiment, it is in a state of being present at a height level position of, for example, 2/3 of the total height with respect to the lower surface of the outer casing 11. As a result, since the floor-to-floor contact surface 15A of the side walls 13A and 13B is curved in an arc shape, the gas detector body 10 is easily tilted.

  As each rechargeable battery 20, for example, a model “VP110” (made by BLACK & DECKER) having a battery voltage of DC 3.6 V is used, and the power supply is indented inward at the center position of the lower end surface. A terminal 21 is provided.

Each rechargeable battery 20 is inserted from above in a state in which the upper part of the battery chamber 12 is opened by rotating the battery chamber cover lid 12A that is bent from the upper surface of the outer casing 11 and continues to the rear surface side. It is attached by.
Specifically, each rechargeable battery 20 is inserted into the battery insertion guide hole 22A of the battery insertion guide plate 22 and the lower end thereof is guided to the negative side contact terminal 23 having a function as an elastic guide member. In a state of being pressed to the side by the minus side contact terminal 23, the plus side protruding terminal 24 provided to protrude from the lower end surface of the battery chamber 12 is fitted to the power supply terminal 21 on the lower end surface of the rechargeable battery 20. Is attached.

The hydrogen gas cylinder includes a gas cylinder main body 42 and a cap 45 that protects a hydrogen gas ejection portion in the gas cylinder main body 42.
The gas cylinder main body 42 includes a pressure-resistant container 41 including a cylindrical portion that forms a neck portion 41A and a bottomed cylindrical portion that forms a trunk portion 41B having a diameter larger than the neck portion 41A that is continuous with the neck portion 41A. On the inner peripheral surface of the neck portion 41A, a neck portion 41A of the pressure vessel 41 is provided with a hydrogen gas jetting portion provided with a hydrogen gas supply valve mechanism that opens and closes a hydrogen gas supply gas flow path to turn on and off the supply of hydrogen gas. For example, it is integrally mounted by being screwed into the formed screw groove.
The pressure vessel 41 is filled with, for example, a powdered (granular) hydrogen storage alloy (not shown) as a hydrogen gas supply source, and the hydrogen gas pressure in the gas cylinder main body 42 is maintained under normal conditions, that is, at normal temperature. Under a pressure environment, for example, about 1 MPa.
In this hydrogen gas cylinder, the functional portion for opening and closing the hydrogen gas supply gas flow path is housed in the neck portion 41A of the pressure-resistant container 41, whereby the hydrogen gas supply valve mechanism is sufficiently protected. Since high explosion-proof property can be obtained, there is a low risk of ignition or explosion and high safety can be obtained.

  A cap 45 that protects the hydrogen gas ejection portion when not attached is connected to the neck portion 41A of the pressure vessel 41 in the hydrogen gas cylinder 40 by a deformable connecting member 44, and the cap 45 is placed inside the outer casing 11. It is held by a cap holding portion (not shown) provided.

In the gas detector main body 10, for supplying hydrogen gas in a high pressure state of about 1 MPa ejected from the gas cylinder main body 42 in a state where the gas pressure is reduced to an appropriate magnitude, for example, 0.05 to 0.3 MPa. A pressure regulator 35 is arranged.
A secondary pressure gauge 36 is connected to the outlet portion of the pressure regulator 35, and the gas supply pressure to the hydrogen gas sensor unit 50 is monitored, and the flow rate adjustment valve 30 is opened or closed based on the monitoring result. Is controlled.

  In FIG. 5, reference numeral 48 denotes a hydrogen gas supply valve mechanism opening / closing knob that opens and closes a hydrogen gas supply valve mechanism that is integrally attached to the gas cylinder main body 42, and this hydrogen gas supply valve mechanism opening / closing knob 48. Is pushed by the detector to open the hydrogen gas supply valve mechanism, and hydrogen gas is ejected from the gas cylinder main body 42.

  The flame ionization type gas detector configured as described above includes, for example, a sample gas sampling nozzle (not shown) for introducing a sample gas (measurement gas) at a measurement location, and a sample gas introduction connector portion of the gas detector body 10. After connecting to 34, the detector carries the gas detector body 10 and carries the sample gas collection nozzle, and is carried by the detector at the measurement location and used.

  When starting the gas measurement, first, the hydrogen gas supply valve mechanism opening / closing knob 48 is pushed by the detector to open the hydrogen gas supply valve mechanism, and the hydrogen gas is supplied to the hydrogen gas. In addition to being supplied to the sensor unit 50 at a predetermined supply amount via the pipes 31A and 31B, the power switch of the gas detector body 10 is turned on, and the sample gas is sucked by the sample gas suction pump 32 to the sensor unit 50. It is supplied at a predetermined supply amount.

  In the sensor unit 50, when the hydrogen gas supplied from the gas cylinder main body 42 is ignited and a hydrogen flame is generated, the sample gas supplied in a state separated from the hydrogen gas is brought into contact with the hydrogen flame. The hydrocarbon contained in the sample gas is thermally decomposed, and the amount of cations generated thereby is detected as a current value. Based on the detection result, the concentration of the hydrocarbon gas contained in the sample gas is detected, and the The result is displayed on the display unit 18.

Thus, according to the flame ionization type gas detector having the above-described configuration, the center of gravity of the gas detector body 10 as a whole exists in the upper half region of the outer casing 11 and the pair of floor surfaces of the gas detector body 10 with respect to the floor. Since the contact surface 15A is curved in an arc shape, if it is left unattended, it cannot stand by the action of gravity and falls down on its own. Therefore, high safety is obtained in terms of management of the gas detector body 10, damage to the components is prevented, and the initial performance is stably maintained.
In other words, since the gas detector main body 10 is intentionally incapable of being independent, when the gas detector main body 10 is managed, the gas detector main body 10 is left standing. Therefore, the detector itself is prohibited from being managed by a predetermined method with high management consciousness, and thus high safety can be obtained.

  Further, the gas detector body 10 is used while being carried on the back of a detector, but even if the outer casing 11 is a thin box shape and is loaded with a hydrogen gas cylinder, for example, 4 to 5 kg. Therefore, since it is configured to be easily carried on the back, there is substantially no obstacle to performing the intended work or the like, and high convenience can be obtained.

  Furthermore, the state where the center of gravity exists in the upper half region is achieved by collecting and arranging main components such as the rechargeable battery 20 and the sensor unit 50 in the upper half region in the outer casing 11. Therefore, the maintainability of the sensor unit 50 and the like can be improved.

As mentioned above, although embodiment of this invention was described, this invention is not limited to said embodiment, A various change can be added.
For example, as long as the position of the center of gravity is arranged in the upper half area of the outer casing, the arrangement position of each component member is not particularly limited.
In addition, the shape of the side surface of the side wall facing the floor is not limited to an arc shape, and may be a shape that falls down when the gas detector body is left unattended.
Further, the hydrogen flame ionization gas detector of the present invention is provided with an alarm notification mechanism for notifying that the hydrogen flame has been extinguished during measurement or that the atmosphere at the measurement location is in a dangerous state. Can be configured.
Furthermore, the hydrogen flame ionization type gas detector of the present invention is a mixture of hydrogen gas and sample gas even if the hydrogen gas and sample gas are separated and supplied to the gas supply unit. Even if it is the thing of the structure supplied to a gas supply part in the performed state, any structure may be sufficient.
Further, in the above embodiment, the case where the gas detector body is used while being carried on the back of the detector has been described, but even when used in a state where the gas detector body is suspended from the shoulder by an appropriate wearing tool, Alternatively, for example, a wheelbarrow for mounting the gas detector main body may be used by running on the ground.

It is a front view which shows the external appearance of the gas detector main body in one structural example of the flame ionization type | mold gas detector of this invention. It is a top view of the gas detector main body shown in FIG. It is a left view of the gas detector main body shown in FIG. It is a right view of the gas detector main body shown in FIG. It is explanatory drawing which shows the outline of a structure inside the gas detector main body shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Gas detector main body 11 Outer casing 12 Battery compartment 12A Battery compartment cover lid 13A, 13B Side wall 14 Tongue piece part 15 Bottom leg part 15A Floor-to-floor contact surface 17 Gas cylinder loading chamber 18 Display part 19 Operation part 20 Rechargeable battery DESCRIPTION OF SYMBOLS 21 Power supply terminal 22 Battery insertion guide plate 22A Battery insertion guide hole 23 Negative side contact terminal 24 Positive side protruding terminal 30 Flow rate adjusting valve 31A, 31B Hydrogen gas supply pipe 32 Sample gas suction pump 33 Sample gas supply pipe 34 Sample gas introduction Connector part 35 Pressure regulator 36 Secondary pressure gauge 41 Pressure vessel 41A Neck part 41B Body part 42 Gas cylinder body 44 Connecting material 45 Cap 48 Hydrogen gas supply valve mechanism opening / closing knob 50 Hydrogen flame ionization sensor part (sensor part)
55 Control unit

Claims (1)

A portable flame ionization type gas detector that is equipped with a thin box-shaped outer casing, in which a flame ionization sensor, a hydrogen gas cylinder, a battery power supply unit, and a circuit board are arranged. A vessel,
The hydrogen flame ionization gas, characterized in that the center of gravity of the entire gas detector exists in the upper half area of the outer casing, and the contact surface to the floor of the gas detector is formed in a state where it cannot stand by itself. Detector.