JP2004257706A - Push-pull type ventilator, and auxiliary air flow generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent exposure of ventilation gas due to a reverse flow generated when a worker stands with his/her back against a push unit. <P>SOLUTION: A device 1 generating an auxiliary air flow F3 for reverse flow suppression apart from an air flow F1 for ventilation is provided in the push-pull type ventilator 101. Air is blown in a direction orthogonal to a direction of the ventilation air flow F1 from the auxiliary air flow generator 1 or a direction slanted more to a downstream side to generate the auxiliary air flow F3 flowing against a reverse flow component F2 of the ventilation gas in a ventilation area A. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a push-pull ventilator, and more particularly, to a technique for preventing exposure of a ventilation gas generated in front of an operator working with a push unit as a back, due to backflow.
[0002]
[Prior art]
The push-pull type ventilator is a ventilator whose use has been legally approved by the recent revision of the dust law and the organic law. 2. Description of the Related Art A push-pull ventilator is known as a ventilator having an advantage of realizing a wide ventilation area and not impairing workability.
[0003]
The push-pull type ventilator is configured to include a push unit that blows out air as ventilation gas, and a pull unit that is installed to face the push unit and sucks a little more gas than the amount of ventilation gas blown out by the push unit. Is done. A substantially uniform flow of ventilation gas (hereinafter referred to as “ventilation airflow”) is generated in the ventilation area between the push unit and the pull unit, and harmful substances are put on the ventilation airflow and discharged out of the system. (Patent Document 1 below).
[0004]
[Patent Document 1]
JP-A-07-214327 (paragraph number 0027)
[0005]
[Problems to be solved by the invention]
However, the push-pull ventilator has the following problems depending on the position of the worker. In other words, if the operator turns the windward airflow away from the ventilation area in the ventilation area, the ventilation gas circulates in front of the operator, creating a backflow of the ventilation gas. There is a risk of receiving it. Although such phenomena have already been reported as research results, no effective countermeasures have been taken.
[0006]
Therefore, the present invention provides a push-pull type ventilation device having a function of effectively preventing exposure by a backflow of ventilation gas generated when an operator turns windward against a ventilation airflow, and a function thereof. An object of the present invention is to provide an auxiliary airflow generating device for realizing the same.
[0007]
[Means for Solving the Problems]
For this reason, in the present invention, the ventilation area is set including the space where the worker is present, and the ventilation gas is blown into the ventilation area from the push unit, and the ventilation gas is sucked out from the ventilation area by the pull unit, and the ventilation area is supplied to the ventilation area. Generate ventilation airflow. On the other hand, the ventilation source is located between the push unit and the pull unit and at a position downstream of the standing position where the worker stands with the push unit as the blow source, from the lower part of the worker's breathing area to the upper part. Auxiliary airflow is generated in the ventilation area by blowing gas in a direction orthogonal to the direction of the airflow or inclined in the downstream direction.
[0008]
A push-pull type ventilation device according to the present invention is a means for generating a ventilation airflow in a ventilation area including a worker's presence space, and is provided at one end of the ventilation area, and a push unit that blows ventilation gas into the ventilation area. A pull unit that is installed at the other end of the ventilation area in opposition to the push unit, and that pulls out the ventilation gas from the ventilation area, and a ventilation airflow generating unit that includes the push unit and the pull unit. And, it is installed downstream of a specific standing position of the worker, and blows out gas in a direction orthogonal to the direction of the ventilation airflow or inclined in the downstream direction to generate an auxiliary airflow in the ventilation area. And auxiliary airflow generating means.
[0009]
According to such a configuration, the backflow of the ventilation gas generated in front of the worker with the windward back relative to the ventilation airflow can be suppressed by the auxiliary airflow, and the exposure of the worker can be prevented.
[0010]
It is preferable that the auxiliary airflow generating means is installed downstream of a standing position where the operator stands behind the push unit.
Further, it is preferable that the auxiliary airflow generating means is installed below the respiratory range of the worker, and the gas blowing direction is set upward from below the respiratory range of the worker.
[0011]
The auxiliary airflow generating device of the push-pull type ventilation device according to the present invention has a blower that sends out a gas for generating an auxiliary airflow at a predetermined air volume, a first portion connected to a discharge side of the blower, A slot portion having a second portion formed to have a width in a direction orthogonal to the gas flow direction from the first portion larger than that of the first portion, and a slot provided in the second portion of the slot portion; And a wind direction adjusting unit that determines the direction in which gas is blown from the unit in a predetermined direction.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a conceptual diagram of workplace ventilation by a push-pull ventilator 101 according to one embodiment of the present invention.
[0013]
The configuration of the push-pull ventilator 101 will be described with reference to FIG. 1. The push-pull ventilator 101 includes a push unit 111 that forms a ventilation gas outlet 111a in a plane perpendicular to the work floor, and a push unit outlet. The push unit 111 and the pull unit 112 constitute a ventilating air flow generating unit according to the present embodiment, including a pair of the port 111a and a pull unit 112 forming a ventilation gas inlet 112a opposed thereto. With the space between the outlet 111a of the push unit and the inlet 112a of the pull unit as the ventilation area A, the push unit 111 is installed at one end of the ventilation area A and has an amount of ventilation gas according to the required ventilation capacity. From the outlet 111a in a direction parallel to the floor of the workplace. The pull unit 112 is provided at the other end of the ventilation area A so as to face the push unit 111, and sucks a slightly larger amount of gas than the amount of ventilation gas blown out by the push unit 111 from the suction port 112a. Note that air is used as the ventilation gas.
[0014]
The push-pull ventilator 101 includes the auxiliary airflow generator 1 as an auxiliary airflow generator.
FIG. 2 is a side view of the auxiliary airflow generation device 1 included in the push-pull type ventilation device 101 according to the present embodiment.
[0015]
The auxiliary airflow generating device 1 uses the air blown by the blower 11 placed on the floor of the workplace into a wide uniform flow through the slot 12, blows it out from the opening of the slot 12, and provides a push-pull ventilator. Auxiliary airflow is generated in the ventilation area A by 101.
[0016]
The slot 12 of the auxiliary airflow generating device 1 is fixedly mounted on a support 13 that keeps the distance from the floor of the workplace to the lower end 12a of the slot constant. The slot 12 is installed upright with respect to the floor of the workplace, and a wind direction adjusting plate 14 that determines the direction in which air is blown from the slot 12 is attached to the upper end 12b. The wind direction adjusting plate 14 is fixed at an angle of 45 ° with respect to the plane including the outlet 12a of the slot. The slot 12 is connected to the blower 11 via an air supply duct 15 at a lower end 12a. By connecting the air supply duct 15 to the slot 12 from the lateral direction, the air sent from the blower 11 flows into the slot 12 from the lateral direction.
[0017]
Reference numeral 21 denotes a transformer for adjusting the discharge amount of the blower 11 (that is, the strength of the auxiliary airflow). By setting the transformer 21, an auxiliary airflow having a wind speed of about 2 to 2.5 m / s is generated. Reference numeral 22 denotes a pedal switch for switching operation and stop of the blower 11.
[0018]
FIG. 3 is a rear view of the auxiliary airflow generation device 1.
The slot 12 of the auxiliary airflow generating device 1 has a lower end portion (corresponding to a "first portion") 12a whose cross-sectional area is smaller than that of an upper end portion (corresponding to a "second portion"). The upper end portion 12b has a uniform cross-sectional area. That is, the air that has flowed into the slot 12 from the air supply duct 15 once loses speed at the lower end portion 12a of the slot, and diffuses and spreads substantially uniformly as it rises in the slot 12 toward the upper end portion 12b. To blow out evenly. The wind speed and the wind direction at this time can be controlled in a predetermined manner by changing the settings of the transformer 21 and the wind direction adjusting plate 14.
[0019]
Next, the operation of the push-pull ventilator 101 according to the present embodiment will be described with reference to FIG.
During operation, a harmful substance source S such as an organic solvent or an object to be welded is placed on the workbench 201 and arranged in the ventilation area A between the outlet 111a of the push unit and the inlet 112a of the pull unit. You. The auxiliary airflow generation device 1 is installed between the push unit 111 and the worktable 201 and immediately beside the worktable 201. In the auxiliary airflow generating device 1, the height of the support table 13 and the length of the slot 12 are set so that the outlet 12c of the slot is substantially the same height as the top plate of the work table 201. When the push unit 111 and the pull unit 112 of the push-pull type ventilation device 101 operate, a uniform ventilation airflow F1 is generated in the ventilation area A. Then, the harmful gas or the like generated from the harmful substance generation source S flows on the ventilation airflow F1 generated in the ventilation area A, is sucked into the pull unit 112, and is discharged from the workplace.
[0020]
Such a ventilation effect can be satisfactorily obtained when the worker W is working at a standing position that is lateral to the ventilation airflow F1. However, when the worker W stands between the outlet 111a of the push unit and the harmful substance generation source S and works with the ventilation airflow F1 on the windward side, the ventilation gas may be in front of the worker W. Turns around as indicated by arrow F2, and flows in the ventilation area A in the opposite direction. When the harmful gas or the like is flown on the backflow component F2 generated as described above, it is highly likely that the harmful gas reaches the worker W and is exposed to a high concentration.
[0021]
Here, when the worker W works at the standing position where the backflow of the ventilation gas is generated, when the pedal switch 22 installed at the foot is pressed, the blower 11 of the auxiliary airflow generating device 1 is operated, and the outlet of the slot is opened. Air is blown out from 12c to form an auxiliary airflow F3 which flows opposite to the backflow component F2 of the ventilation gas. The auxiliary airflow F3 is set to a predetermined wind direction and a predetermined wind speed by the wind direction adjusting plate 14 and the transformer 21. The auxiliary airflow F3 serves to push the backflow component F2 downstream, so that the harmful gas or the like reaches and the worker W is exposed. Is prevented.
[0022]
According to the present embodiment, the following effects can be obtained.
First, since the auxiliary airflow generating device 1 is provided to generate the auxiliary airflow F3, the ventilation gas generated when the worker W works on the ventilation airflow F1 with the windward side as the back. Can be suppressed by the auxiliary airflow F3, and the worker W can be prevented from being exposed. An organic solvent handling workplace was reproduced in a laboratory using a full-scale model, and the auxiliary airflow generating device 1 according to the present embodiment was installed and operated there, and a ventilation airflow having a wind speed of 0.8 m / s was generated. It was confirmed that the organic solvent exposure concentration to the worker could be reduced from 220 ppm to 0.8 ppm under certain conditions.
[0023]
Secondly, since the auxiliary airflow F3 is generated by the wind direction adjustment plate 14 in a direction at 45 ° to the direction of the ventilation airflow F1, the backflow of the ventilation gas can be suppressed well.
[0024]
Third, since the outlet 12c of the slot is set at substantially the same height as the top plate of the worktable 201, and the auxiliary airflow F3 is generated from below the breathing area of the worker W to above, the backflow component The harmful gas or the like flowing from the harmful substance generation source S toward the worker W on the F2 can be satisfactorily escaped, and the exposure can be reliably prevented.
[0025]
Fourth, since the pedal switch 22 is installed at the foot of the worker W to switch the operation and the stop of the auxiliary airflow generation device 1, the auxiliary airflow F3 can be generated only when necessary, and economical. It is.
[0026]
In the above description, the case where the height of the slot outlet 12c is constant has been described as an example. However, a flexible duct that can expand and contract is interposed in a duct portion connecting the slot 12 and the blower 11 and a support base is provided. By incorporating a mechanism capable of adjusting the height in 13, it is possible to correspond to the position of the harmful substance generation source S according to the height of the work table 201.
[0027]
Further, by setting the installation angle of the wind direction adjusting plate 14 to be variable and changing the installation angle in accordance with the state of occurrence of the backflow of the ventilation gas, it is possible to always obtain a favorable backflow suppression effect.
[Brief description of the drawings]
FIG. 1 is a conceptual diagram of workplace ventilation by a push-pull ventilator according to one embodiment of the present invention. FIG. 2 is a side view of an auxiliary airflow generator of the push-pull ventilator. Rear view of [Description of symbols]
101: Push-pull ventilator, 111: Push unit, 112: Pull unit, 1: Auxiliary airflow generator, 11: Blower, 12: Slot, 12a: Lower end of slot as first part, 12b: Second , The upper end of the slot as a part, 12c ... the outlet of the slot, 13 ... the support base, 14 ... the wind direction adjustment plate, 21 ... the transformer, 22 ... the pedal switch as a switch, A ... ventilation area, F1 ... ventilation air flow, F2: backflow component of ventilation gas, F3: auxiliary airflow, S: harmful substance source.

Claims (7)

Means for generating a ventilation airflow in a ventilation area including a space where the worker is present, wherein the push unit is installed at one end of the ventilation area and blows ventilation gas into the ventilation area; A pull unit that is installed at the end and that extracts the ventilation gas from the ventilation area, and
It is installed between the push unit and the pull unit and downstream from the specific standing position of the worker, and directs the gas in a direction orthogonal to the direction of the ventilation airflow or inclined downstream from it. A push-pull ventilator configured to include an auxiliary airflow generating unit that blows out air to generate an auxiliary airflow in the ventilation area. 2. The push-pull type ventilator according to claim 1, wherein the auxiliary airflow generating means is installed at a downstream side of a standing position where the worker stands behind the push unit. 3. The push-pull type ventilator according to claim 2, wherein the auxiliary airflow generating means is provided below the worker's breathing area, and the blowing direction of the gas is set upward from below the worker's breathing area. 4. The push-pull ventilator according to claim 3, wherein the auxiliary airflow generating means is set such that a gas blowing direction forms an angle of approximately 45 degrees with a direction of the ventilation airflow. 5. The switch according to claim 2, further comprising: a switch that is installed near a standing position where the operator is behind the push unit and that switches between an operation for generating an auxiliary airflow and another stop. A push-pull ventilator as described in Crab. The ventilation area is set to encompass the worker's presence space, and while the ventilation gas is blown into the ventilation area from the push unit, the ventilation gas is drawn out from the ventilation area by the pull unit, and the ventilation air flow is generated in the ventilation area,
Using the position between the push unit and the pull unit and downstream from the standing position where the operator stands behind the push unit as the blow source, the ventilation airflow A push-pull ventilator that generates auxiliary airflow in the ventilation area by blowing gas in a direction that is orthogonal to the direction or inclined downstream from the direction. A device that generates auxiliary airflow separately from the ventilation airflow in the ventilation area of the push-pull type ventilation device,
A blower that sends out a gas for generating an auxiliary airflow at a predetermined air volume,
A first portion connected to the discharge side of the blower, and a second portion formed to have a width greater than that of the first portion in a direction perpendicular to a gas flow direction from the first portion. A slot part,
An auxiliary airflow generating device provided at a second portion of the slot portion and including a wind direction adjusting portion that determines a direction in which gas is blown from the slot portion in a predetermined direction.

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