FORM 2
THE PATENTS ACT, 1970 (39 of 1970)
As amended by the Patents (Amendment) Act, 2005
&
The Patents Rules, 2003
As amended by the Patents (Amendment) Rules, 2006
COMPLETE SPECIFICATION (See section 10 and rule 13)
TITLE OF THE INVENTION Pedestal fan
APPLICANTS
Crompton Greaves Limited, CG House, Dr Annie Besant Road, Worli, Mumbai 400 030,
Maharashtra, India, an Indian Company
INVENTORS
Bhat Amit and Khan Ahmed, both of Crompton Greaves Limited, Fans Division, Plot No 1 , Goa
IDC Industrial Estate, Bethora, Ponda, Goa- 403409, India, both Indian Nationals
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to
be performed:

FIELD OF THE INVENTION
This invention relates to a pedestal fan.
BACKGROUND OF THE INVENTION
A pedestal fan comprises a drive motor having fan blades mounted on the housing of the motor and provided with a guard and an upright mount assembly. The upright mount assembly comprises an outer tube and an inner tube up and down slidably held in the outer tube. The mount assembly also comprises a base provided with castor wheels at the bottom thereof and a mounting hub at the top centre thereof. The lower end of the outer tube and the inner surface of the sidewall of the hub are provided with threads and the threaded lower end of the outer tube is located in the mounting hub in thread engagement therewith. The rotation movement of the outer tube in the hub is prevented by a bolt having its edge tightened against the lower end of the outer tube through a lateral hole in the outer tube. The base also comprises a cover located over the top surface thereof. A bottom cup is tightened over the outer tube towards the bottom thereof and a top cup is tightened over the upper end of the outer tube. The upper end outer surface of the outer tube is threaded and the top cup is provided with internal threads and tightened over the upper end of the outer tube in thread engagement therewith. The inner tube is held in position with a knob having its edge tightened against the inner tube through a lateral hole in the top cup. The fan motor with the blades and guard is mounted at the upper end of the inner shaft. Because of the thread engagement between the lower end of the outer tube and hub it is necessary to maintain precise and close tolerances between the hub and the lower end of the outer tube. In case close and precise tolerances are not maintained between the hub and the lower end of the outer tube the fit between the two will become loose and the outer tube with the fan motor,

blades and guard will start shaking and vibrating. Further, because of the threading of the lower end of the outer tube and the inner surface of the sidewall of the hub, manufacturing time and cost are increased. Due to the thread fit between the upper end outer surface of the outer tube and the top cup, on tightening the top cup against the upper end outer surface of the outer tube, there are possibilities for the upper end outer surface of the outer tube to get damaged or to crack as the upper end outer surface of the outer tube would have been already weakened because of the threading provided in the less thickness outer pipe. As a result, the life of the mount assembly is reduced.
OBJECTS OF THE INVENTION
An object of the invention is to provide a pedestal fan which is simple in construction and cost
effective.
Another object of the invention is to provide a pedestal fan which' requires reduced manufacturing time and cost.
Another object of the invention is to provide a pedestal fan which has a sturdy and strong mount assembly and has increased life.
DETAILED DESCRIPTION OF THE INVENTION
According to the invention there is provided a pedestal fan comprising a fan motor having blades mounted on the housing of the fan motor and a guard and an upright mount assembly, the mount assembly comprising an outer tube and an inner tube up and down movably held in the outer

tube, the outer tube having a bottom cup fitted over the outer tube towards the bottom thereof and a mounting flange at the lower end thereof having mounting holes, a base provided with castor wheels at the bottom thereof and mounting holes at the top thereof matching with the mounting holes in the mounting flange, the upper tube being mounted on the base at the top thereof with bolts tightened in the mounting holes in the mounting flange and the top of the base, a base cover located over the top of the base around the outer tube, the outer tube being externally threaded at the upper end thereof and having a reinforcing insert located therein, the insert extending along the threaded upper end outer surface of the outer tube, a top cover having internal threads corresponding to the threading at the upper end outer surface of the outer tube and disposed over the inner tube and tightened over the threaded upper end outer surface of the outer tube, the inner tube being tightened in position with a knob having its edge tightened against the inner tube through a lateral hole in the top cup, the fan motor with blades and guard being mounted at the top end of the inner tube.
The following is a detailed description of the invention with reference to the accompany . drawings, in which :
Fig 1 is a disassembled elevation of a pedestal fan according to an embodiment of the invention;
Fig 2 is a view of the mounting flange of the pedestal fan of Fig 1; and
Fig 3 is a view of the outer tube of the pedestal fan of Fig 1.

The pedestal fan 1 as illustrated in Figs 1 to 3 of the accompanying drawings comprises fan motor 2 having fan blades 3 mounted on the housing of the fan motor and provided with a fan guard 4. The pedestal fan also comprises an upright mount assembly 5 having an outer tube 6 and an inner tube 7 up and down slidably held in the outer tube. The outer tube comprises a bottom cup 8 tightened over it towards the bottom thereof and a mounting flange 9 at the bottom thereof. The mounting flange is provided with mounting holes 10 and reinforcing ribs 11. The reinforcing ribs are to save material of the mounting flange but at the same time reinforce the mounting flange. However the reinforcing ribs of the mounting flange are optional. 12 is a base provided with castor wheels at the bottom thereof. The shafts 13 of the castor wheels are tightened in engaging holes 14 provided in the base. The top of the base is provided with mounting holes 15 corresponding to the mounting holes in the mounting flange. The outer tube is mounted on the base by engaging bolts 16 in the mounting holes in the flange and corresponding mounting holes at the top of the base and tightening with nuts 16a. 17 is a base cover located over the top of the base around the outer tube. The upper end outer surface of the outer tube is provided with threads 18. 19 is a reinforcing insert located within upper end of the outer tube. The insert extends along the externally threaded upper end of the outer tube. 20 is a top cup provided with threads internally (not shown) matching with the threads at the upper end outer surface of the outer tube. The top cup is disposed over the inner tube and tightened over the upper end outer surface of the outer tube in thread engagement therewith. The rotational movement of the inner tube is prevented by tightening the edge 21 of a knob 22 against the inner tube through a lateral hole 23 in the top cup. The fan motor with the fan blades and fan guard are mounted at the top end of the inner tube. The fan height can be adjusted by loosening the knob

and moving the inner tube with the fan motor, fan blades and fan guard up and down in the outer tube and the inner tube can be locked in position by tightening the knob.
According to the invention the tube at the centre of the top of the base and thread engagement between the lower end of the outer tube and the hub and associated bolt have been eliminated. Mounting of the outer tube at the top of the base by bolting is easy and convenient to carry out. The fit between the outer tube and base is rigid and sturdy and there are no chances for the outer tube with the fan motor, blades and guard to shake and vibrate. As the thread fit between the lower end of the outer tube and the base have been eliminated, manufacture of the fan assembly is easy and convenient and reduces time manufacturing time. As the upper end of the outer tube is reinforced with the reinforcing insert, chances for the upper end of the outer tube to get damaged or deformed or to crack during tightening of the top cup at the upper end of the outer tube are eliminated. Therefore, the life of the mount assembly and hence that of the pedestal fan is increased.

We claim
1) A pedestal fan comprising a fan motor having blades mounted on the housing of the fan motor and a guard and an upright mount assembly, the mount assembly comprising an outer tube and an inner tube up and down movably held in the outer tube, the outer tube having a bottom cup fitted over the outer tube towards the bottom thereof and a mounting flange at the lower end thereof having mounting holes, a base provided with castor wheels at the bottom thereof and mounting holes at the top thereof matching with the mounting holes in the mounting flange, the upper tube being mounted on the base at the top thereof with bolts tightened in the mounting holes in the mounting flange and the top of the base, a base cover located over the top of the base around the outer tube, the outer tube being externally threaded at the upper end thereof and having a reinforcing insert located therein, the insert extending along the threaded upper end outer surface of the outer tube, a top cover having internal threads corresponding to the threading at the upper end outer surface of the outer tube and disposed over the inner tube and tightened over the threaded upper end outer surface of the outer tube, the inner tube being tightened in position with a knob having its edge tightened against the inner tube through a lateral hole in the top cup, the fan motor with blades and guard being mounted at the top end of the inner tube.
2) The pedestal fan as claimed in claim 1, wherein the mounting flange comprises reinforcing ribs provided thereon.