Apparatus for allowing ventilation for underground tunnels through a ventilation shaft opening to atmosphere yet preventing underground flooding from surface waters pouring through the grate comprises an assembly that fits within the ventilation shaft and includes one or more panels mounted on a pivot axis and rotatable upwardly by human action raising the panel past a center point of the pivot axis to an upright inwardly leaning home position that allows ventilation as usual but by manual push or pull of the panels past the center point of the pivot axis lets the panels rotationally fall under gravitational impetus to a lower sealing position closing a passage between the ventilation shaft and atmosphere to prevent water from entering the underground tunnels.

Apparatus for allowing ventilation for underground tunnels through a ventilation shaft opening to atmosphere yet preventing underground flooding from surface waters pouring through the grate comprises an assembly that fits within the ventilation shaft and includes one or more panels mounted on a pivot axis and rotatable upwardly by human action raising the panel past a center point of the pivot axis to an upright inwardly leaning home position that allows ventilation as usual but by manual push or pull of the panels past the center point of the pivot axis lets the panels rotationally fall under gravitational impetus to a lower sealing position closing a passage between the ventilation shaft and atmosphere to prevent water from entering the underground tunnels.

Provided is a blower installed at a manhole opening, with which it is possible to facilitate an entry or an exit of a worker or an import or an export of an article. The present invention provides a ventilation system comprising a frame and a single or a plurality of airflow generation means arranged at the frame, a direction of an airflow is adjusted so that the airflow generated from the airflow generation means flows along with a virtual axis penetrating a virtual surface which the frame is regarded as to periphery, and the airflow flows while swallowing up the surrounding air of the virtual axis, and an air volume more than two times of total fluid volume of the airflow is generated.

Provided is a blower installed at a manhole opening, with which it is possible to facilitate an entry or an exit of a worker or an import or an export of an article. The present invention provides a ventilation system comprising a frame and a single or a plurality of airflow generation means arranged at the frame, a direction of an airflow is adjusted so that the airflow generated from the airflow generation means flows along with a virtual axis penetrating a virtual surface which the frame is regarded as to periphery, and the airflow flows while swallowing up the surrounding air of the virtual axis, and an air volume more than two times of total fluid volume of the airflow is generated.

A tunnel ventilation system located in an upper section of a tunnel has a ventilation section divided into two or three ventilation ducts. One or more of the ducts are connected to reversible fan units so the ducts can serve as either an air infeed or an air exhaust system. The ducts contain a series of remotely controlled flaps which can be opened to ventilate different tunnel zones or closed to isolate other parts of the tunnel. Air blowers at tunnel entrances create an air screen that prevents unintended air circulation into the tunnel. Heat, smoke and other sensors and a software control system enable the system to detect smoke and fire, then to isolate and control ventilation in the fire zone. A fire suppression system using low oxygen air or other fire suppression fluids to blanket and smother the fire operates in conjunction with the ventilation system.

A tunnel ventilation system located in an upper section of a tunnel has a ventilation section divided into two or three ventilation ducts. One or more of the ducts are connected to reversible fan units so the ducts can serve as either an air infeed or an air exhaust system. The ducts contain a series of remotely controlled flaps which can be opened to ventilate different tunnel zones or closed to isolate other parts of the tunnel. Air blowers at tunnel entrances create an air screen that prevents unintended air circulation into the tunnel. Heat, smoke and other sensors and a software control system enable the system to detect smoke and fire, then to isolate and control ventilation in the fire zone. A fire suppression system using low oxygen air or other fire suppression fluids to blanket and smother the fire operates in conjunction with the ventilation system.

A coal and gas outburst monitoring device includes the insertion and anchoring assembly, and the pump drainage and monitoring mechanism; the insertion and anchoring assembly is vertically inserted and distributed on the sidewall of surrounding rock of coal mine roadway, and the insertion and anchoring assembly can monitor the stress change data in the sidewall of surrounding rock in real time; the pump drainage and monitoring mechanism is erected within the coal mine roadway, and the pump drainage and monitoring mechanism can cooperate with the insertion and anchoring assembly to perform the gas pump drainage monitoring for the sidewall of surrounding rock of goaf, and to obtain the gas seepage monitoring data in the surface layer and the inner layer of sidewall of surrounding rock. Thus, comparing with the database mechanism, the accurate and advanced predictions for the gas outburst can be made.

A coal and gas outburst monitoring device includes the insertion and anchoring assembly, and the pump drainage and monitoring mechanism; the insertion and anchoring assembly is vertically inserted and distributed on the sidewall of surrounding rock of coal mine roadway, and the insertion and anchoring assembly can monitor the stress change data in the sidewall of surrounding rock in real time; the pump drainage and monitoring mechanism is erected within the coal mine roadway, and the pump drainage and monitoring mechanism can cooperate with the insertion and anchoring assembly to perform the gas pump drainage monitoring for the sidewall of surrounding rock of goaf, and to obtain the gas seepage monitoring data in the surface layer and the inner layer of sidewall of surrounding rock. Thus, comparing with the database mechanism, the accurate and advanced predictions for the gas outburst can be made.

A roof-mounted ventilator comprising a plurality of blades is disclosed. Each blade comprises front and back blade faces and leading and trailing edges. When the ventilator is viewed in side profile, the blades are positioned and configured such that a line of sight into the interior of the ventilator is substantially restricted or obstructed. Restricting or obstructing the line of sight into the ventilator can reduce or prevent various particles, such as water droplets, debris, dust and light, from entering the ventilator interior. For example, rain is thereby forced to strike a face of the blades, thus preventing direct access into the ventilator interior. The blade itself may include additional features, such as a lip that extends along the length of the leading edge, to further prevent particles from entering the ventilator interior, or to redirect the particles away from the ventilator interior in a controlled manner.

A roof-mounted ventilator comprising a plurality of blades is disclosed. Each blade comprises front and back blade faces and leading and trailing edges. When the ventilator is viewed in side profile, the blades are positioned and configured such that a line of sight into the interior of the ventilator is substantially restricted or obstructed. Restricting or obstructing the line of sight into the ventilator can reduce or prevent various particles, such as water droplets, debris, dust and light, from entering the ventilator interior. For example, rain is thereby forced to strike a face of the blades, thus preventing direct access into the ventilator interior. The blade itself may include additional features, such as a lip that extends along the length of the leading edge, to further prevent particles from entering the ventilator interior, or to redirect the particles away from the ventilator interior in a controlled manner.