This concept is very new, and it will allow for safe and continuous operation of gas heating units when the induced draft fan no longer operates. This device will allow the HVAC service technician to continue to operate the gas heating unit until the proper replacement induced draft fan can be acquired and installed on the gas heating unit. This invention is a supplemental induced draft fan that will attach to the exhaust output side of a gas heating units inoperable induced draft fan to draft air through the heat exchanger and create a vacuum to the pressure switch at a rate to be regulated by a control switch to make the gas heating unit operate safely until the correct part is acquired and installed.

An exhaust fan assembly can include an outer housing, a fan housing mounted to the outer housing, a fan wheel and an electric motor operably coupled to the fan wheel, the fan wheel and electric motor being mounted within the fan housing, wherein the fan housing defines an open inlet side for accepting airflow in a direction generally parallel to a rotational axis of the fan wheel and an outlet for discharging airflow in a direction generally perpendicular to the rotational axis, wherein the fan housing defines a volute section with an outer perimeter having a continuously curved cross-sectional shape.

The invention relates to turbo molecular pumps enabling high pumping speed. The disclosure suggests using one or more cage-like rotor stages to optimize pumping speed on vacuum systems with low gas flows and low ultimate pressures. This allows for a smaller motor as well as smaller overall form factor and makes it well suited, in particular, for compact mass spectrometers and desk-top mass spectrometers.

The invention relates to turbo molecular pumps enabling high pumping speed. The disclosure suggests using one or more cage-like rotor stages to optimize pumping speed on vacuum systems with low gas flows and low ultimate pressures. This allows for a smaller motor as well as smaller overall form factor and makes it well suited, in particular, for compact mass spectrometers and desk-top mass spectrometers.

In a refrigeration unit for use in cooling a space, such as a walk-in cold space, or other system, an easy access fan motor assembly is provided. A motor mount holds the motor with a plurality of legs that couple to a front panel using stud inserts. In some instances the legs are curved and looked like spider legs. A fan guard member covers the fan and is also attached to the stud inserts. By removing fasteners on the stud inserts, the guard member may be removed and the fan motor assembly may be removed from a position exterior to the refrigeration unit for repair or serving. Other systems and methods are disclosed.

A fan engagement structure for the fan to quickly and securely plug into or extract out of another structure. The fan engagement structure includes a frame main body. The frame main body has a first end and a second end. The frame main body has an internal hollow passage. The first end is mated with a fan. The frame main body has a first side and a second side. An engagement elastic plate extends from the first side. The surface of the engagement elastic plate has a latch section. The second side has a finger latch section, whereby the fan can be quickly and securely plugged into or extracted out of the other structure.

A heat dissipating fin assembly includes a bottom, a plurality of first heat dissipating fins, a plurality of second heat dissipating fins, an inner cover and an outer cover. The first heat dissipating fins extend from an inner end toward an outer end. The second heat dissipating fins are arranged between two of the first heat dissipating fins in staggered. The inner cover is disposed near the inner end and connected to the first heat dissipating fins. The outer cover is disposed near the outer end and connected to the second heat dissipating fins. The inner cover and the outer cover are separated to form an opening, and the dusts entering the heat dissipating fin assembly through the inner end are ejected via the opening. The second heat dissipating fins extend from around the opening to the outer end.

A heat dissipating fin assembly includes a bottom, a plurality of first heat dissipating fins, a plurality of second heat dissipating fins, an inner cover and an outer cover. The first heat dissipating fins extend from an inner end toward an outer end. The second heat dissipating fins are arranged between two of the first heat dissipating fins in staggered. The inner cover is disposed near the inner end and connected to the first heat dissipating fins. The outer cover is disposed near the outer end and connected to the second heat dissipating fins. The inner cover and the outer cover are separated to form an opening, and the dusts entering the heat dissipating fin assembly through the inner end are ejected via the opening. The second heat dissipating fins extend from around the opening to the outer end.

A ventilation and heat dissipation apparatus of a wind-assisted rotor includes a cylinder (2), a top cover (3), and a rain shielding plate (4). The top cover (3) is disposed at the top of the cylinder (2) and covers the top of the cylinder (2), and the top cover (3) is provided with a manhole (1) communicating with an inner cavity of the cylinder (2). The rain shielding plate (4) is disposed above the manhole (1) and covers the manhole (1), and the rain shielding plate (4) and the top cover (3) are spaced apart to form a heat dissipation gap that communicates with an external atmosphere.

A ventilation and heat dissipation apparatus of a wind-assisted rotor includes a cylinder (2), a top cover (3), and a rain shielding plate (4). The top cover (3) is disposed at the top of the cylinder (2) and covers the top of the cylinder (2), and the top cover (3) is provided with a manhole (1) communicating with an inner cavity of the cylinder (2). The rain shielding plate (4) is disposed above the manhole (1) and covers the manhole (1), and the rain shielding plate (4) and the top cover (3) are spaced apart to form a heat dissipation gap that communicates with an external atmosphere.