Vacuum cleaner

Claim 2

A vacuum cleaner comprising a housing having a dust space that is provided with a dust bag as placed therein, a motor space having a blower and a motor for driving said blower, said blower being in communication with said dust space for drawing air through the dust space and into said motor space, a shroud connected with the exhaust of said blower and having a plurality of air outlet ports but otherwise surrounding such motor air-tightly, an air filter mounted on said shroud on the outside of said air outlet ports thereof in such a way that air emerging from said air outlet ports passes through said air filter, and air air space as defined between said shroud and said housing for receiving air as discharged through said air filter from said air outlet ports of said shroud, said housing including air exit ports through which air may be discharged from said air space, and said shroud including a valve member formed in the wall thereof, said valve member opening at a given gauge pressure in said shroud so that the air drawn in is able to emerge from said shroud.

Claim 3

A vacuum cleaner as specified in claim 1, and wherein said valve member comprises a flap formed in the wall of said shroud.

Claim 4

A vacuum cleaner as specified in claim 2, and wherein the opening of said flap may be selectively indicated optically, electrically and acoustically.

Claim 5

A vacuum cleaner comprising a housing having a dust space that is provided with a dust bag as placed therein, a motor space having a blower and a motor for driving said blower, said blower being in communication with said dust space for drawing air through the dust space and into said motor space, a shroud connected with the exhaust of said blower and having a plurality of air outlet ports but otherwise surrounding said motor air-tightly, an air filter mounted on said shroud on the outside of said air outlet ports thereof in such a way that air emerging from said air outlet ports passes through said air filter, a cassette frame within which is fitted said filter whereby the same may be bodily mounted on and removed from said shroud, said shroud including a frame surrounding the outlet ports thereof and into which said filter cassette frame may be inserted with an air-tight jointing effect, and an air space as defined between said shroud and said housing for receiving air as discharged through said air filter from said air outlet ports of said shroud, said housing including a plurality of air exit ports through which air may be discharged from said air space, said air exit ports being distributed over a substantial area of said housing and of a substantially large cross sectional area such that air as received by said housing is released through said air exit ports at a low pressure, said air exit ports of said housing being in juxtaposed relation to said air outlet ports of said shroud and said air space whereby air emerges with a low velocity and a wide distribution from the air exit ports of said housing.

Claim 6

A vacuum cleaner comprising a housing having a dust space that is provided with a dust bag as placed therein, a motor space having a blower and a motor for driving said blower, said blower being in communication with said dust space for drawing air through the dust space and into said motor space, a shroud connected with the exhaust of said blower and having a plurality of air outlet ports but otherwise surrounding said motor air-tightly, an air filter mounted on said shroud on the outside of said air outlet ports thereof in such a way that air emerging from said air outlet ports passes through said air filter, a cassette frame within which is fitted said filter whereby the same may be bodily mounted on and removed from said shroud, said shroud including a frame surrounding the outlet ports thereof and into which said filter cassette frame may be inserted with an air-tight jointing effect, and an air space as defined between said shroud and said housing for receiving air as discharged through said air filter from said air outlet ports of said shroud, said housing including a plurality of air exit ports through which air may be discharged from said air space, said air exit ports being distributed over a substantial area of said housing and of a substantially large cross sectional area such that air as received by said housing is released through said air exit ports at a low pressure, said air exit ports of said housing being in juxtaposed relation to said air outlet ports of said shroud and said air space whereby air emerges with a low velocity and a wide distribution from the air exit ports of said housing.

Claim 7

A vacuum cleaner as specified in claim 4 and wherein said surrounding frame includes rails for supporting said filter cassette frame.

Claim 8

A vacuum cleaner as specified in either of claims 4 or 5 and wherein said filter is a fine filter and a handle is provided for said filter cassette frame.

Claim 9

A vacuum cleaner as specified in any of claims 1, 2, 3, 4 or 5, and wherein said shroud includes a bearing ring for said blower, ribs being provided for connection of said bearing ring to said shroud.

Claim 10

A vacuum cleaner as specified in any of claims 1, 2, 3, 4 or 5, and wherein said shroud consists of a material with elastomer components.

Claim 11

A vacuum cleaner comprising a housing having a dust space that is provided with a dust bag as placed therein, a motor space having a blower and a motor for driving said blower, said blower being in communication with said dust space for drawing air through the dust space and into said motor space, a shroud connected with the exhaust of said blower and having a plurality of air outlet ports but otherwise surrounding said motor air-tightly, an air filter mounted on said shroud on the outside of said air outlet ports thereof in such a way that air emerging from said air outlet ports passes through said air filter, a cassette frame within which is mounted said filter whereby the same may be bodily mounted on and removed from said shroud, said cassette frame including a handle to facilitate mounting and removal thereof from said shroud, said filter comprising a fine filter, and an air space as defined between said shroud and said housing for receiving air as discharged through said air filter from said air outlet ports of said shroud, said housing including a plurality of air exit ports through which air may be discharged from said air space, said air exit ports being distributed over a substantial area of said housing and of a substantially large cross sectional area such that air as received by said housing is released through said air exit ports at a low pressure, said air exit ports of said housing being in juxtaposed relation to said air outlet ports of said shroud and said air space whereby air emerges with a low velocity and a wide distribution from the air exit ports of said housing.

Claim 12

A vacuum cleaner comprising a housing having a dust space that is provided with a dust bag as placed therein, a motor space having a blower and a motor for driving said blower, said blower being in communication with said dust space for drawing air through the dust space and into said motor space, a shroud connected with the exhaust of said blower and having a plurality of air outlet ports but otherwise surrounding said motor air-tightly, an air filter mounted on said shroud on the outside of said air outlet ports thereof in such a way that air emerging from said air outlet ports passes through said air filter, a cassette frame within which is mounted said filter whereby the same may be bodily mounted on and removed from said shroud, said cassette frame including a handle to facilitate mounting and removal thereof from said shroud, said filter comprising a fine filter, and an air space as defined between said shroud and said housing for receiving air as discharged through said air filter from said air outlet ports of said shroud, said housing including a plurality of air exit ports through which air may be discharged from said air space, said air exit ports being distributed over a substantial area of said housing and of a substantially large cross sectional area such that air as received by said housing is released through said air exit ports at a low pressure, said air exit ports of said housing being in juxtaposed relation to said air outlet ports of said shroud and said air space whereby air emerges with a low velocity and a wide distribution from the air exit ports of said housing.