JP3198576U - Suction gas detector - Google Patents

Abstract

To provide a suction type gas detector in which gas detection is not interrupted even if an operator's hand accidentally touches and closes a gas inlet. SOLUTION: A gas introduction port 3, a gas discharge port 24, a gas flow path P communicating with the gas introduction port 3 and the gas discharge port 24, a gas suction means 23, a gas detection element 22, and a gas flow path. A suction-type gas detector comprising a blockage detection unit 25 for detecting a blockage state of P, and a control unit 26 for stopping the suction operation by the gas suction unit 23 when the blockage detection unit 25 detects the blockage state. A penetrating part 4 that communicates the gas flow path P and the outside separately from the port 3 is provided on the upstream side of the gas flow path P with respect to the gas detection element 22, the gas suction means 23, and the blockage detection means 25. A suction-type gas detector comprising a return unit 27 for restarting the gas suction means 23 stopped by the above operation in a state in which the obstruction is removed from the gas flow path P. [Selection] Figure 6

Description

  The present invention includes a gas introduction port through which gas is introduced, a gas discharge port through which gas is discharged, a gas flow path that connects the gas introduction port and the gas discharge port, and the gas introduction port through the gas introduction port. A gas suction means for sucking gas into the gas flow path; a gas detection element for detecting the gas sucked into the gas flow path; a blockage detection means for detecting a blockage state of the gas flow path; and the blockage detection means. The present invention relates to a suction type gas detector including a control unit that stops a suction operation by the gas suction means when a closed state is detected.

  As a conventional suction type gas detector, for example, the one shown in Patent Document 1 is known. Here, only one small gas inlet is provided at the tip of the nozzle.

Japanese Patent Laid-Open No. 2002-52306 (FIG. 1)

  If water or the like is accidentally sucked from the gas introduction port, the gas flow path may be blocked with water or the like, and may adhere to the gas detection element and cause a failure.

  In order to prevent this in the conventional suction type gas detector, the blockage detection means detects that the gas flow path has entered by detecting the blockage state of the gas flow path, and then the control unit detects the gas suction means. The suction operation is stopped, and further infiltration of water or the like is prevented to prevent the gas from adhering to the gas detection element.

  However, the above-described operation of the blockage detection means is not limited to blockage due to the intrusion of water or the like, but is also triggered simply by the operator's hand or piping touching the gas inlet accidentally and temporarily blocking it. It had been.

  Therefore, even though the gas flow path is not actually blocked by water or the like, it is mistakenly recognized that the gas flow path is blocked, and each time the gas suction means stops and gas detection is interrupted. As a result, gas could not be detected properly.

  An object of the present invention is to provide a suction type gas detector in which gas detection is not interrupted even if an operator's hand accidentally touches and closes a gas inlet.

  The characteristic configuration of the suction type gas detector according to the present invention includes: a gas introduction port through which gas is introduced; a gas discharge port through which gas is discharged; and a gas flow path that connects the gas introduction port and the gas discharge port A gas suction means for sucking gas into the gas flow path through the gas introduction port, a gas detection element for detecting the gas sucked into the gas flow path, and detecting a closed state of the gas flow path A suction type gas detector comprising: a blockage detection unit; and a control unit that stops a suction operation by the gas suction unit when the blockage detection unit detects a blockage state, wherein the gas flow path is separated from the gas introduction port. The gas suction unit stopped by the control unit is provided on the upstream side of the gas flow path with respect to the gas detection element, the gas suction unit, and the blockage detection unit. Blocked from the gas flow path In that it comprises a return section for restarting in a state it has been removed.

[Action and effect]
According to this configuration, even if an operator's hand accidentally touches the gas inlet and closes it, the gas can be introduced through the through portion that communicates the gas flow path with the outside. Will not be interrupted.

  In addition, according to this configuration, even if an operator's hand accidentally touches both the gas inlet and the penetrating part and closes it, the clogging detecting means is activated and the control part is operated by the gas suction means. Even when the suction operation is stopped, the gas suction means can be restarted promptly by operating the return portion.

It is the front view (a) and perspective view (b) of the suction type gas detector of this invention. It is a longitudinal cross-sectional view in the arrow line II-II of FIG. It is a disassembled perspective view of a nozzle part. It is a perspective view of an attachment member of another form. FIG. 5 is a cross-sectional view taken along line VV in FIG. 2. It is a schematic block diagram of the suction type gas detector of this invention. It is the front view (a) and sectional drawing (b) of a gas exhaust port. It is the front view (a) and longitudinal cross-sectional view (b) of the gas discharge port after mounting | wearing a protrusion member. It is the front view (a) and longitudinal cross-sectional view (b) of the gas exhaust port after mounting | wearing with an adapter member.

  As an embodiment of the suction gas detector of the present invention, a portable suction gas detector will be described with reference to the drawings.

Embodiment
As shown in FIGS. 1A and 1B, the suction type gas detector according to the present embodiment includes a vertically long conical nozzle portion 1, a main body portion 20 including a gas detection element, a gas suction means, and the like. Is provided.

(Nozzle part)
As shown in FIGS. 2 and 3, the nozzle portion 1 includes an attachment member 2, a joint member 6, and a filter case 7.

  The attachment member 2 is made of a flexible material (rubber or the like), and includes an elongated cylindrical small-diameter portion 2a and a large-diameter portion 2b having an outer diameter larger than that of the small-diameter portion 2a. 2a and the large diameter part 2b are integrally molded. Moreover, the attachment member 2 has the through-hole P1 penetrated to a longitudinal direction over the small diameter part 2a and the large diameter part 2b.

  In the small-diameter portion 2a of the attachment member 2, an opening formed at the tip opposite to the large-diameter portion 2b is a gas introduction port 3 for introducing the gas G to be detected. In addition, a through portion 4 that communicates the through hole P1 of the small diameter portion 2a and the outside is provided on the side surface of the small diameter portion 2a of the attachment member 2 on the gas inlet 3 side.

  By providing this penetration part 4, even if an operator's hand accidentally touches and closes the gas introduction port 3, the external gas G is introduced into the gas flow path P through the penetration part 4. .

  In addition to the configuration of the penetrating portion 4 described above, a notched portion 5 that is notched from the gas inlet 3 to the side surface of the attachment member 2 may be provided as shown in FIG. Even with this configuration, even if the operator's hand or the like accidentally touches the gas inlet 3 to block it, the external gas G is introduced into the gas flow path P through the notch 5.

  As shown in FIGS. 2 and 3, the attachment member 2 is prevented from coming off by the nipple portion 6 a of the joint member 6, but can be removed by pulling with some force. Therefore, it can be appropriately replaced with an attachment member having a shape more suitable for the situation, for example, an attachment member having a longer shape, if necessary.

  The joint member 6 includes a nipple portion 6a having a tapered surface continuous in the longitudinal direction on the outer peripheral surface, and a large diameter portion 6b having an outer diameter larger than that of the nipple portion 6a. The nipple portion 6a and the large diameter portion 6b include It is molded integrally. The joint member 6 has a through hole P2 that penetrates in the longitudinal direction across the nipple portion 6a and the large diameter portion 6b.

  The filter case 7 includes an upper portion 8 of a hollow cylindrical member, a lower portion 9 of the same hollow cylindrical member, and a disk-shaped filter member 14 for removing water droplets and dust contained in the gas G. With.

  The upper part 8 and the lower part 9 of the filter case 7 are configured so as to be fitted and connected to each other. When the filter member 14 and the O-ring R1 are arranged in the lower portion 9 and one end of the upper portion 8 is fitted into the lower portion 9, the upper portion 8 An accommodation space 15 in which the filter member 14 can be accommodated is formed between the lower portion 9 and the filter member 14 is accommodated in the accommodation space 15.

  A trap member T that reduces the flow rate of the gas G is provided at an intermediate position inside the upper portion 8 of the filter case 7.

  As shown in FIGS. 2 and 5, the trap member T includes a convex portion 10 that rises toward the gas inlet 3, and a concave portion 11 that is formed between the convex portion 10 and the inner peripheral surface of the upper portion 8. Prepare. In this embodiment, the concave portion 11 extends from the inner peripheral surface of the upper portion 8 to the lower portion 9 side and is connected to an end portion different from the top plate 13 side of the convex portion 10, so that the cross-sectional shape is V-shaped. It has become a shape.

  A plurality of flow holes 12 through which the gas G can flow are formed in a portion extending from the top plate 13 to the side wall of the convex portion 10. The top plate 13 (collision part) of the convex part 10 is arranged on the axis of the through hole P3 of the upper part 8.

  As shown in FIG. 3, after the nozzle portion 1 externally fits the large-diameter portion 6b of the joint member 6 to the upper portion 8 of the filter case 7 via the O-ring R2, the nipple portion 6a of the joint member 6 is fitted. The attachment member 2 can be assembled by being pushed into the opening of the large diameter portion 2b. At this time, the shaft center of the through hole P1 of the attachment member 2, the shaft center of the through hole P2 of the joint member 6, and the shaft center of the through hole P3 of the upper portion 8 and the through hole P4 of the lower portion 9 of the filter case 7 are Each is configured to match.

  As shown in FIGS. 1A, 1 </ b> B, and 2, the nozzle portion 1 has a main body portion on the opposite side of the lower portion 9 of the filter case 7 from the side on which the upper portion 8 is fitted. The main body portion 20 is mounted by being externally fitted to a mounting portion (not shown) protruding from the upper surface of the main body 20.

(Main body)
As shown in FIG. 6, the main body 20 includes a cylindrical housing 21 that forms part of the gas flow path P, a gas detection element 22 that detects a gas to be detected, and a diaphragm pump 23 (gas) that sucks the gas. Suction means), gas discharge port 24 through which gas is discharged, flow sensor 25 (blockage detection means) for detecting the flow rate of gas G flowing through the gas flow path P, and diaphragm pump 23 when the flow sensor 25 detects a blockage state. A control unit 26 that stops the suction operation and a release switch 27 (return unit) that restarts the diaphragm pump 23 stopped by the control unit 26 are configured.

  Examples of the gas G that can be detected by the suction gas detector of the present invention include flammable gases such as methane, toxic gases such as carbon monoxide and hydrogen sulfide, and odors.

  Further, the gas detection element 22 applicable to the suction type gas detector of the present invention can be appropriately selected according to the type of the gas G to be detected. For example, on the surface of the metal oxide semiconductor Measures the electrical conductivity change due to gas adsorption as a change in resistance value seen from both ends of the platinum wire coil, and detects the gas by detecting the gas. A constant potential electrolytic detection element for detecting gas, a gas thermal conductivity detection element for detecting gas by measuring a temperature change of a heating element (platinum wire coil) due to a difference in thermal conductivity of the gas, and a catalyst surface And a catalytic combustion type detecting element for detecting a gas by measuring a temperature rise of a platinum wire coil due to gas catalytic combustion.

  One end of the housing 21 is connected to a mounting portion (not shown) of the main body 20, and the other end is connected to the gas discharge port 24. Thereby, the gas introduction port 3 of the nozzle part 1 and the gas discharge port 24 of the main-body part 20 are connected, and the gas flow path P through which the gas G flows is formed. That is, the gas flow path P is formed from the upstream side of the through hole P1 (see FIG. 2) of the attachment member 2 of the nozzle portion 1, the through hole P2 of the joint member 6 (see FIG. 2), and the upper portion 8 of the filter case 7. The through hole P3 (see FIG. 2), the through hole P4 (see FIG. 2) of the lower portion 9, and the housing 21 of the main body 20 are formed to communicate with each other.

  In the housing 21, a gas detection element 22, a flow sensor 25, and a diaphragm pump 23 are arranged in this order from the upstream side of the gas flow path P.

  As shown in FIGS. 1 (a) and 1 (b), the gas discharge port 24 opens on the lateral side surface of the main body 20. As shown in FIGS. 7A and 7B, a circular wall portion 28 is erected on the lateral side surface of the main body portion 20 so as to surround the gas discharge port 24. The wall portion 28 is provided with a communication portion 29 that allows the gas discharge port 24 to communicate with the outside.

  Also, as shown in FIGS. 8A and 8B, a projecting member 30 having a cross-shaped cross section is provided detachably with respect to the gas discharge port 24. As shown in FIG. 8A, the gas discharge port 24 is divided into four by the protruding member 30, and gas is discharged from these four gaps. Further, as shown in FIG. 8B, the protruding member 30 is fitted into the gas discharge port 24 while being locked to the periphery of the gas discharge port 24 in a state of protruding outward from the gas discharge port 24. .

  9A and 9B, an adapter member 31 that is a hollow cylindrical member can be attached to the gas discharge port 24 instead of the protruding member 30. The adapter member 31 is formed by adhering a rubber member that is in close contact with the inner peripheral surface of the gas discharge port 24 and a polycarbonate member that protrudes from the gas discharge port 24. The adapter member 31 is attached to the adapter member 31. Further, by connecting a hose or the like, the exhausted gas G can be guided to another measuring device and further analysis can be performed.

[Description of operation]
As shown in FIG. 2, the gas G sucked from the gas inlet 3 of the nozzle portion 1 by driving the diaphragm pump 23 passes through the through hole P1 of the attachment member 2 and the through hole P2 of the joint member 6, and then passes through the filter. Colliding with the top plate 13 of the convex portion 10 of the trap member T of the case 7, the flow velocity is once decelerated. Thereby, the gas G passes through the flow hole 12 of the convex portion 10 while the dust having a slightly larger particle size contained in the gas G is captured in the concave portion 11 of the trap member T.

  Next, the gas G reaches the filter member 14, and water droplets and fine dust contained in the gas G are removed.

  The gas G that has passed through the filter member 14 passes through the through hole P4 in the lower portion 9 of the filter case 7 and is introduced into the housing 21 of the main body 20.

  As shown in FIG. 6, the gas G introduced into the housing 21 is detected by the gas detection element 22, and the detection result is sent to the control unit 26 via the gas detection element drive circuit 32 connected to the gas detection element 22. Is output.

  The flow sensor 25 detects the closed state of the gas flow path P by detecting the flow rate of the gas G flowing through the gas flow path P. The flow rate detected by the flow sensor 25 is output as a signal to the control unit 26 via the flow sensor drive circuit 33 connected to the flow sensor 25.

  The gas G that has passed through the gas detection element 22 and the flow sensor 25 passes through the diaphragm pump 23 and is discharged from the gas discharge port 24.

  When the gas G is being sucked, for example, when water or the like enters the gas flow path P of the nozzle unit 1 to prevent the gas G from being sucked, the flow sensor 25 causes the gas G flowing through the gas flow path P to flow. It is detected that the flow rate is less than the predetermined gas flow rate, and is output to the control unit 26 via the flow sensor drive circuit 33.

  The control unit 26 to which this signal is input immediately stops the suction operation by the diaphragm pump 23 to prevent water or the like from entering the housing 21 of the main body unit 20.

  Next, the diaphragm pump 23 stopped by the control unit 26 is restarted by turning on the release switch 27 provided in the main body unit 20 with the obstruction such as water removed from the gas flow path P. Can be made.

  The suction type gas detector according to the present invention can be used to detect various gases such as flammable gas, toxic gas, and odor.

DESCRIPTION OF SYMBOLS 1 Nozzle part 2 Attachment member 2a Small diameter part 2b Large diameter part 3 Gas inlet 4 Penetration part 5 Notch part 6 Joint member 6a Nipple part 6b Large diameter part 7 Filter case 8 Upper part 9 Lower part 10 Convex part 11 Concave part 12 Flow hole 13 Top plate (collision part)
14 Filter member 15 Accommodating space 20 Main body 21 Housing 22 Gas detection element 23 Diaphragm pump (gas suction means)
24 Gas outlet 25 Flow sensor (blockage detection means)
26 Control Unit 27 Release Switch (Return Unit)
28 Wall part 29 Communication part 30 Projection member 31 Adapter member 32 Gas detection element drive circuit 33 Flow sensor drive circuit P Gas flow path P1-P4 Through-hole R1, R2 O-ring T Trap member

Claims (1)

A gas inlet through which gas is introduced; a gas outlet through which gas is discharged; a gas flow path communicating with the gas inlet and the gas outlet; and the gas flow path through the gas inlet. Gas suction means for sucking gas, gas detection element for detecting the gas sucked into the gas flow path, blockage detection means for detecting the blockage state of the gas flow path, and the blockage detection means detecting the blockage state Then, a suction type gas detector comprising a control unit for stopping the suction operation by the gas suction means,
In addition to the gas inlet, a penetrating portion that communicates the gas flow path and the outside is provided on the upstream side of the gas flow path from the gas detection element, the gas suction means, and the blockage detection means,
A suction-type gas detector comprising a return unit that restarts the gas suction unit stopped by the control unit in a state in which a blockage is removed from the gas flow path.

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