Motor-fan unit for moving wet working air

Claim 2

In an electric motor fan unit, including an electric motor section having motor frame structure supporting and enclosing rotor and stator structure with motor ventilating air passages defined therethrough from a ventilating air inlet to a motor frame portion at one end open for discharge of ventilating air, said frame structure at said one end including a motor end bracket having therein a bearing for the rotor shaft extending therethrough and having an end rim portion with ventilating air discharging open frame areas around the locus of the bearing, and said unit further including a fan section having therein at least one main working air impeller clamped outboard on the shaft portion extending through said bearing and a fan housing structure including housing shell means providing an end wall centrally apertured to form an axial working air inlet to said main impeller and a further wall circumferentially surrounding the said mAin impeller, said housing shell means having therein main air outlet means and having an open end supported on said end rim portion, that improvement comprising: partition means mounted to said rim portion and forming an inmost end wall of said housing structure, said inmost end wall centrally apertured providing around said shaft an axial inlet to said housing for ventilating air discharging from said motor section; and a centrifugal ventilating air impeller secured on said shaft between said main impeller and said inmost end wall; said impellers being separate impeller units secured back-toback on the shaft in a common chamber defined between the said end walls and with the impeller inlet openings facing the respective said axial inlets, whereby ventilating air and working commonly discharge through said main air outlet means.

Claim 3

An electric motor fan unit improvement as described in claim 1 with said main air outlet means offset away from the periphery of the main impeller toward said inmost wall, and said ventilating air impeller having a smaller diameter than said main impeller, whereby ventilating air discharging from the smaller impeller sweeps the space between said inmost wall and the working air path of discharge to said main outlet means.

Claim 4

An electric motor fan unit improvement as described in claim 1, with said partition means provided by a cup-shaped member having a short cylindrical wall portion fitted and secured on the exterior of said rim portion and a generally radial, centrally apertured wall portion as said inmost end wall, and said housing shell having its open end fitted over the cylindrical wall portion of the last said member and thereby secured to said rim portion.

Claim 5

An electric motor fan unit improvement as described in claim 1, with said partition means provided by a centrally apertured disk-like member forming said inmost end wall and secured to said end bracket and circumferentially sealing to said rim portion, and said housing shell means having said open end fitted on the said rim portion.

Claim 6

An electric motor fan unit improvement as described in claim 1, including a spacer sleeve on said shaft, with one end abutting a part of said bearing axially fixed on and rotating with said shaft and having on its other end a radial flange supporting portions of said ventilating and main impellers centrally apertured for successive reception of the shaft, and clamping nut means threaded onto the outboard shaft to clamp said impellers against the said flange.

Claim 7

In an electric motor fan unit, including an electric motor section having motor frame structure supporting and enclosing rotor and stator structure with motor ventilating air passages defined therethrough from a ventilating air inlet to a motor frame portion at one end open for discharge of ventilating air, said frame structure at said one end including a motor end bracket having therein a bearing for the rotor shaft extending therethrough and having an end rim portion with ventilating air discharging open frame areas around the locus of the bearing, and said unit further including a fan section having therein at least one main working air impeller clamped outboard on the shaft portion extending through said bearing and a fan housing structure including housing shell means providing an end wall centrally apertured to form an axial working air inlet to said main impeller and a further wall circumferentially surrounding the main impeller, said housing shell means having therein main air outlet means and having an open end supported on said end rim portion, that improvement comprising: partition means mounted to said rim portion and forming an inmost end wall of said housing structure, said inmost end wall centrally apertured providing around said shaft an axial inlet to said housing for ventilating air discharging from said motor section; and a centrifugal ventilating air impellEr secured on said shaft between said main impeller and said inmost end wall, further separate partition means supported on said rim portion and providing a centrally apertured intermediate wall dividing said housing structure into an outer, main impeller chamber and an inner, ventilating air impeller chamber, means supporting said ventilating impeller in the respective said chamber axially spaced outboard from said bearing, and spacer sleeve means supporting said meain impeller spaced on said shaft from said ventilating impeller and located in the other said chamber, and clamping nut means threaded onto the outboard shaft end to clamp the last said impeller.

Claim 8

In an electric motor fan unit, including an electric motor section having motor frame structure supporting and enclosing rotor and stator structure with motor ventilating air passages defined therethrough from a ventilating air inlet to a motor frame portion at one end open for discharge of ventilating air, said frame structure at said one end including a motor end bracket having therein a bearing for the rotor shaft extending therethrough and having an end rim portion with ventilating air discharging open frame areas around the locus of the bearing, and said unit further including a fan section having therein at least one main working air impeller clamped outboard on the shaft portion extending through said bearing and a fan housing structure including housing shell means providing an end wall centrally apertured to form an axial working air inlet to said main impeller and a further wall circumferentially surrounding the main impeller, said housing shell means having therein main air outlet means and having an open end supported on said end rim portion, that improvement comprising: partition means mounted to said rim portion and forming an inmost end wall of said housing structure, said inmost end wall centrally apertured providing around said shaft an axial inlet to said housing for ventilating air discharging from said motor section; and a centrifugal ventilating air impellEr secured on said shaft between said main impeller and said inmost end wall, further separate partition means supported on said rim portion and providing a centrally apertured intermediate wall dividing said housing structure into an outer, main impeller chamber and an inner, ventilating air impeller chamber, means supporting said ventilating impeller in the respective said chamber axially spaced outboard from said bearing, and spacer sleeve means supporting said meain impeller spaced on said shaft from said ventilating impeller and located in the other said chamber, and clamping nut means threaded onto the outboard shaft end to clamp the last said impeller.

Claim 9

An electric motor fan unit improvement as described in claim 6, with the said further partition means provided by a member having a short cylindrical wall portion with an open end secured on the said rim portion and a generally radial, centrally apertured wall portion as said intermediate wall, and said housing shell means having its open end secured on the cylindrical wall portion of the last said member and thereby supported on said rim portion.

Claim 10

An electric motor fan unit improvement as described in claim 7, with the first said partition means provided by a centrally apertured disk-like member as said inmost end wall and having a circumferential flange of narrow u-shaped cross section press-fitted into said rim portion.

Claim 11

An electric motor fan unit improvement as described in claim 7, wherein the cylindrical wall of said further partition means is provided with a plurality of equi-spaced apertures for discharge of air from the ventilating air impeller chamber.

Claim 12

An electric motor fan unit improvement as described in claim 7, wherein said ventilating air impeller has a smaller diameter than the main impeller, and said intermediate wall is provided with a circular series of apertures spaced outwardly of the periphery of the ventilating air impeller as air outlets for the ventilating impeller chamber to the main impeller chamber, whereby ventilating air and working air streams discharge commonly from the main impeller chamber through said main air outlet means.

Claim 13

An electric motor fan unit improvement as described in claim 10, with said main air outlet means comprising a circumferential series of spaced air outlet apertures adjacent said intermediate wall in the cylindrical wall portion of said housing shell, said main impeller spaced axially from the intermediate wall beyond the locus of the last said series, and said circular series located radially between the peripheries of said impellers, whereby ventilating air discharging from the ventilating impeller chamber sweeps the space between said intermediate wall and the working air path of discharge to said main impeller outlet means.

Claim 14

An electric motor fan unit improvement as described in claim 6, wherein the aperture of said intermediate wall has a close running clearance with said spacer sleeve means extending therethrough.

Claim 15

In an electric motor fan unit, including an electric motor section having motor frame structure supporting and enclosing rotor and stator structure with motor ventilating air passages defined therethrough from a ventilating air inlet to a motor frame portion at one end open for discharge of ventilating air, said frame structure at said one end including a motor end bracket having therein a bearing for the rotor shaft extending therethrough and having an end rim portion with ventilating air discharging open frame areas around the locus of the bearing, and said unit further including a fan section having therein at least one main working air impeller clamped outboard on the shaft portion extending through said bearing and a fan housing structure including housing shell means providing an end wall centrally apertured to form an axial working air inlet to said main impeller and a further wall circumferentially surroundiNg the said main impeller, said housing shell means having therein main air outlet means and having an open end supported on said end rim portion, that improvement comprising: partition means mounted to said rim portion and forming an inmost end wall of said housing structure, said inmost end wall centrally apertured providing around said shaft an axial inlet to said housing for ventilating air discharging from said motor section; and a centrifugal ventilating air impeller secured on said shaft between said main impeller and said inmost end wall; said housing shell means comprising a cup-shaped member integrally providing the end wall having said axial working air inlet and a cylindrical wall for circumferentially surrounding said main impeller, said cylindrical wall having therein said main air outlet means and having its open end supported on a cylindrical formation on said rim portion; said partition means secured at the external circumference thereof to said rim portion and including a centrally apertured disk-like member as said inmost end wall and having a circumferential flange of narrow U-shaped cross section press fitted into said portion.

Claim 16

In an electric motor fan unit, including an electric motor section having motor frame structure supporting and enclosing rotor and stator structure with motor ventilating air passages defined therethrough from a ventilating air inlet to a motor frame portion at one end open for discharge of ventilating air, said frame structure at said one end including a motor end bracket having therein a bearing for the rotor shaft extending therethrough and having an end rim portion with ventilating air discharging open frame areas around the locus of the bearing, and said unit further including a fan section having therein at least one main working air impeller clamped outboard on the shaft portion extending through said bearing and a fan housing structure including housing shell means providing an end wall centrally apertured to form an axial working air inlet to said main impeller and a further wall circumferentially surroundiNg the said main impeller, said housing shell means having therein main air outlet means and having an open end supported on said end rim portion, that improvement comprising: partition means mounted to said rim portion and forming an inmost end wall of said housing structure, said inmost end wall centrally apertured providing around said shaft an axial inlet to said housing for ventilating air discharging from said motor section; and a centrifugal ventilating air impeller secured on said shaft between said main impeller and said inmost end wall; said housing shell means comprising a cup-shaped member integrally providing the end wall having said axial working air inlet and a cylindrical wall for circumferentially surrounding said main impeller, said cylindrical wall having therein said main air outlet means and having its open end supported on a cylindrical formation on said rim portion; said partition means secured at the external circumference thereof to said rim portion and including a centrally apertured disk-like member as said inmost end wall and having a circumferential flange of narrow U-shaped cross section press fitted into said portion.

Claim 17

An electric motor fan unit improvement as described in claim 13, wherein said partition means further includes a cup-shaped member with open end fitted on said rim portion and providing a centrally apertured intermediate wall dividing said housing structure into an outer, main impeller chamber and an inner, ventilating air impeller chamber, and means supporting said ventilating and main impellers in the respective said chambers axially successively spaced from said bearing; said housing shell having its open end fitted on the cylindrical wall portion of the last said member and thereby supported on said rim portion.