Abstract: A cyclonic portable vacuum cleaner/dust collector has a cyclonic chamber and a filter chamber. The filter chamber contains a filter cartridge with a hollow core positioned over the discharge opening of a motor plate that closes the filter chamber. A vacuum blower is mounted on the motor plate, with an intake tube at the discharge opening of the motor plate. An anti-deflagration screen mounted upon the discharge opening of the cover plate of the filter chamber. The anti-deflagration screen is in the form of a metal mesh creating a multiplicity of small passages to permit exhaust air flow from the filter chamber but blocking any flame front. The screen may be hemispherically domed.

Abstract: A stacking modular filter arrangement may be employed as a final filter for the dust collector for woodshop or other environment in which dust in an air stream is separated out and the exhausted air is filtered in the final filter to return to the ambient. The filter arrangement employs at least first and second filter modules of similar section, and a number of clamp members to hold facing end plates of the filter modules and pull the end plates against one another with one or more gasket members compressed between them. This arrangement permits the available filter area of the final filter to be customized to the customer's needs.

Abstract: A cyclonic portable vacuum cleaner/dust collector has a cyclonic chamber and a filter chamber. The filter chamber contains a filter cartridge with a hollow core positioned over the discharge opening of a motor plate that closes the filter chamber. A vacuum blower is mounted on the motor plate, with an intake tube at the discharge opening of the motor plate. An annular pulse-cleaning plate is positioned over an associated annular opening that surrounds the motor plate discharge opening and has an open center that slides up and down on the intake tube of the vacuum blower. A bail handle or lever extends from the pulse-cleaning plate to a handle portion outside the cover or shroud. The handle is pushed down to lift the pulsing plate to provide a reverse pressure air pulse to the filter to blast off accumulated dust. An anti-deflagration screen may be present at the center of the motor plate.

Abstract: A stacking modular filter arrangement may be employed as a final filter for the dust collector for woodshop or other environment in which dust in an air stream is separated out and the exhausted air is filtered in the final filter to return to the ambient. The filter arrangement employs at least first and second filter modules of similar section, and a number of clamp members to hold facing end plates of the filter modules and pull the end plates against one another with one or more gasket members compressed between them. This arrangement permits the available filter area of the final filter to be customized to the customer's needs.

Abstract: A level detector or sensor for a dust collection system has a threaded housing that seats in a penetration in the lid of a dust collection drum or other container, and can be adjusted mechanically in its mounting. The sensor has an adjustment to control the distance at which it picks up light off the collected material. An elongated flexible cable connects the sensor with an alarm strobe, which may be a low-power LED device, and can be positioned at a convenient location remote from the drum.

Abstract: A dust collection system has a cyclone separator in which dust is separated from an air stream and the air stream is passed from a separator and flows through a final filter back into the ambient air. A flame arrester is positioned downstream of the separator, either in advance of or after the final filter. The flame arrester defines a multiplicity of narrow channels to permit exhaust air flow but block any flame front. In a preferred embodiment the flame arrester is in the form of a sheath of a porous metal material surrounding the final filter. The sheath may comprise a metal wire mesh screen, with a guard cage surrounding the screen.

Abstract: A dust collection arrangement employs a variable frequency drive to supply AC to its fan motor. A current sensor measures the current drawn by the motor, and this is compared with a preset value. The variable frequency drive adjusts the frequency of the AC applied to the motor to maintain the motor current at the preset level. This keeps the flow of air in the system optimal as dust producing tools are added or taken off.

Abstract: A dust collector arrangement has a dust separator supported on a frame, with a lid for the dust collection barrel is mounted onto the frame below it. The lid is supported at a fixed elevation above the surface of the shop floor to create a space or clearance between the rim of the dust collection barrel and the lid. The barrel is supported on casters, and can be rolled into place under the rim, and can be rolled out for emptying. Over-center latches positioned at intervals around the upper part of the barrel side wall, engage corresponding structure on the lid. These pull the barrel upwards against the lid and with the barrel casters lifted off the floor surface. The latch members release to lower the barrel for emptying.

Abstract: A cyclonic dust collector arrangement employs a cyclone that has a conic body formed of a conic wall. An upper divider plate closes off the upper end of the conic body, with a vortex tube descending from a central passage in the divider plate. The conic body has a narrow nose at a lower end so that the upper divider plate and the lower nose define a cyclonic chamber within the conic body. The inlet conduit penetrates the conic wall below the divider plate. The fan chamber of the separator is mounted above the divider plate, and serves to induce air flow from the inlet conduit into the cyclonic chamber, and through said vortex tube into the fan chamber. The air is discharged through a final filter. This construction has reduced manufacture costs and improved dust separation.

Abstract: A shop vacuum cleaner has a series of dust separation stages, with the large majority of the dust being preseparated in a cyclonic separator and deposited into a first drum or barrel. The remaining dust is carried in the air stream is filtered out in a pre-filter in a second vacuum cleaner drum. A final filter cartridge is fitted onto the intake of the vacuum head. The vacuum cleaner machine exhausts clean, filtered air into the ambient.

Abstract: An auxiliary dust collection system can be interposed between a sander or other dust producing tool and a vacuum source, e.g., shop vacuum. A cyclonic separator is connected by a flexible hose to the tool and by another hose to the vacuum source. The cone of the separator is mounted onto the lid of a drum into which the dust precipitates. For a tool that has its own blower, the vacuum source can be omitted, and the air leaving the outlet duct of the separator can be filtered and returned to the ambient. A drop in silencer formed of a sleeve or tube of acoustic foam can be positioned into the inlet side of a filter cartridge following a cyclonic separator. The silencer absorbs a significant fraction of the process noise. The acoustic foam can have a textured surface on the sound-facing side.

Abstract: A dust collection system for portable sanding or grinding equipment employs a cyclone separator mounted directly on the tool or machine, with a dust outlet duct at the narrow lower end of the cyclone, and a cartridge air filter mounted on the top of the cyclone. The filter returns the air flow from the machine to the ambient air in the vicinity of the tool. The dust is concentrated in the cyclone, and a small volume air flow then moves the dust through an elongated flexible hose or duct to a remote dust collection station. An air pump at the remote dust collection station provides sufficient air flow to draw the small volume of air plus entrained dust from the tool-mounted cyclonic separator. A cyclonic separator at the remote station separates this dust from the air flow and deposits it in a collection tank or drum.

Abstract: A dust collection system for portable sanding or grinding equipment employs a cyclone separator mounted directly on the tool or machine, with a dust outlet duct at the narrow lower end of the cyclone, and a cartridge air filter mounted on the top of the cyclone. The filter returns the air flow from the machine to the ambient air in the vicinity of the tool. The dust is concentrated in the cyclone, and a small volume air flow then moves the dust through an elongated flexible hose or duct to a remote dust collection station. An air pump at the remote dust collection station provides sufficient air flow to draw the small volume of air plus entrained dust from the tool-mounted cyclonic separator. A cyclonic separator at the remote station separates this dust from the air flow and deposits it in a collection tank or drum.

Abstract: A dust collection system for portable sanding or grinding equipment employs a cyclone separator mounted directly on the tool or machine, with a dust outlet duct at the narrow lower end of the cyclone, and a cartridge air filter mounted on the top of the cyclone. The filter returns the air flow from the machine to the ambient air in the vicinity of the tool. The dust is concentrated in the cyclone, and a small volume air flow then moves the dust through an elongated flexible hose or duct to a remote dust collection station. An air pump at the remote dust collection station provides sufficient air flow to draw the small volume of air plus entrained dust from the tool-mounted cyclonic separator. A cyclonic separator at the remote station separates this dust from the air flow and deposits it in a collection tank or drum.