Claims:We claim:
1. A table, pedestal, and wall (TPW) fan (300) for high air delivery, the TPW fan (300) comprising:
a single phase concentric winding induction motor (100);
characterized in that
a fan blade unit (200) mounted to shaft of the single phase concentric winding induction motor (100), wherein the fan blade unit (200) comprises:
a hub (201) at center;
a plurality of blades (202) extending away from the hub (201), wherein each blade from the plurality blades (202) has a lift angle (206) in range of 3o to 5o and twist angles (203, 204, 205) in range 19o to 14o.
2. The TPW fan (300) as claimed in claim 1, wherein each blade from the plurality of blades (202) has a hub end (202a) proximal to the shaft and a tip end (202b) at distal end of the blade (202).
3. The TPW fan (300) as claimed in claim 1, wherein the plurality of blades (202) has atleast five blades.
4. The TPW fan (300) as claimed in claim 2, wherein the each blade from the plurality of blades (202) tapering down from the tip end (202b) to the hub end (202a), the tip end (202b) is wider than the hub end (202a).
5. The TPW fan (300) as claimed in claim 1, wherein the each blade from the plurality of blades (202) define a convex shape profile.
6. The TPW fan (300) as claimed in claim 1, wherein the each blade from the plurality of blades (202) has section at EE, FF, and GG from the hub end (202a) to the tip end (202b) at variable distance from each other, the section EE which is closer to the hub end (202a) has twist angle in range 17o to 19o, the section FF has twist angle in range 16o to 17o, and the section GG has twist angle in range 15o to 16o.
7. The TPW fan (300) as claimed in claim 1, wherein depth of the each blade is in range 2mm to 5mm from the hub end (202a) to the tip end (202b).
8. The TPW fan (300) as claimed in claim 1, wherein the each blade () has lift angle is in range 4o to 6o, preferably 4.50o.
9. The TPW fan (300) as claimed in claim 1, wherein radius of circle define by the fan blade unit (200) is in range 390 mm to 400 mm.
10. The TPW fan (300) as claimed in claim 1, wherein the fan blade unit (200) is made of SAN (Styrene Acrylonitrile).
, Description:HIGH VELOCITY TABLE, PEDESTAL AND WALL FAN (TPW)
FIELD OF INVENTION:
[001] The present subject matter described herein, relates to table, wall, and pedestal (TPW) fan, and, in particular to, high speed table, wall, and pedestal (TPW) fan having single phase concentric winding induction motor and optimized fan blade unit. More particularly, the fan blade unit has variable twist angle along length of the blade for higher air delivery.
BACKGROUND AND PRIOR ART:
[002] Generally, table, wall, and pedestal (TPW) fan are powered by multi phase induction motor. Existing TPW fans can be classified into two categories w.r.t. no. of poles and RPM – namely 2 pole and 4 pole category, specified as High speed and Normal speed range of fan respectively.
[003] The existing TPW fan has high revolution per minute (RPM) with respect to low air delivery. Further, power consumption of the TPW fans are also high if compared with air delivery. With increase in air delivery, the TPW fans create lot of noise.
[004] Existing TPW fans comes with conventional fan blade unit and multi pole winding which do not provide required efficiency in terms of air delivery, air velocity and power consumption. There is need to develop TPW fan which gives the maximum air delivery, air velocity with less noise and less power consumption.
OBJECTS OF THE INVENTION:
[005] The principal objective of the present invention is increase performance of TPW fan by reducing the power consumption while achieving the better Air Delivery and High Air Velocity.
[001] Another object of the present invention is to reduce noise in induction motor at low and medium speed point.
[006] Yet another object of the present invention is to provide a simple and cost effective TPW fan with single phase concentric winding and optimized design leaf blade unit.
SUMMARY OF THE INVENTION:
[007] The present subject matter relates to a table, wall, and pedestal (TPW) fan with single phase concentric winding induction motor with a plurality of blades. The present TPW fan has single phase concentric winding induction motor and a fan blade unit having atleast five blades with optimized twist and lift angle. The fan blade unit has a hub center to mount the fan blade unit with shaft of the induction motor and a plurality of blades extending away from the hub to define circular profile of the fan blade unit. Each blade from the plurality of blades has lift angle in range 3o to 5o and twist angle in range 14o to 19o along length of the blade. The twist angle decreases non-uniformly from the hub end to the tip end.
[008] In order to further understand the characteristics and technical contents of the present subject matter, a description relating thereto will be made with reference to the accompanying drawings. However, the drawings are illustrative only but not used to limit scope of the present subject matter.
BRIEF DESCRIPTION OF THE DRAWINGS
[009] It is to be noted, however, that the appended drawings illustrate only typical embodiments of the present subject matter and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments. The detailed description is described with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system or methods in accordance with embodiments of the present subject matter are now described, by way of example, and with reference to the accompanying figures, in which:
[0010] Fig. 1 illustrates single phase concentric winding, in accordance with an embodiment of the present subject matter;
[0011] Fig. 2a and 2b illustrate structure of fan blade unit, in accordance with the present subject matter;
[0012] Fig. 3 illustrates variable twist angle, variable thickness, variable depth along length of the fan blade unit, in accordance with an embodiment of the present subject matter;
[0013] Fig. 4a, 4b, and 4c illustrate twist angle with various cross section of the fan blade unit as shown in the fig. 3, in accordance with an embodiment of the present subject matter;
[0014] Fig. 5 illustrates lift angle of the fan blade unit, in accordance with an embodiment of the present subject matter; and
[0015] Fig. 6a, 6b, and 6c illustrate table, wall, and pedestal fan, in accordance with an embodiment of the present subject matter.
[0016] The figures depict embodiments of the present subject matter for the purposes of illustration only. A person skilled in the art will easily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DESCRIPTION OF THE PREFERRED EMBODIMENTS:
[0017] The present subject matter relates to a table, wall, and pedestal (TPW) fan with single phase concentric winding induction motor with a plurality of blades. The present TPW fan has single phase concentric winding induction motor and a fan blade unit having at least five blades with optimized twist and lift angle. The fan blade unit has a hub centre to mount the fan blade unit with shaft of the induction motor and a plurality of blades extending away from the hub to define circular profile of the fan blade unit. Each blade from the plurality of blades has lift angle in range 3o to 5o and twist angle in range 14o to 19o along length of the blade. The twist angle decreases non-uniformly from the hub end to the tip end.
[0018] It should be noted that the description and figures merely illustrate the principles of the present subject matter. It should be appreciated by those skilled in the art that conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present subject matter. It should also be appreciated by those skilled in the art that by devising various arrangements that, although not explicitly described or shown herein, embody the principles of the present subject matter and are included within its spirit and scope. Furthermore, all examples recited herein are principally intended expressly to be for pedagogical purposes to aid the reader in understanding the principles of the present subject matter and the concepts contributed by the inventor(s) to furthering the art, and are to be constructed as being without limitation to such specifically recited examples and conditions. The novel features which are believed to be characteristic of the present subject matter, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures.
[0019] These and other advantages of the present subject matter would be described in greater detail with reference to the following figures. It should be noted that the description merely illustrates the principles of the present subject matter. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described herein, embody the principles of the present subject matter and are included within its scope.
[0020] Fig. 1 illustrates diagrammatic view of single phase concentric winding of induction motor, in accordance with the present subject matter. The single phase concentric winding of induction motor is well known and a person skilled in the art knows about working of the winding. Therefore, the present specification has brief information about the winding.
[0021] Fig. 1 illustrates block diagram of concentric winding method for speed /torque control in TPW fan induction motor.
[0022] In Low speed point: Supply live point connected via switch with tapping at point (LOW) with 4 poles (A1.1, A2, A3.1, A4.1) in Auxiliary winding. So 4 Poles remain in Main winding as well as in Auxiliary winding. No pole difference causing no electrical imbalance between Run and Start winding. Free from imbalance noise in motor.
[0023] In Medium speed point: Supply live point connected via switch with tapping at point (MEDIUM) with 4 poles (A1.2, A2.2, A3.2, A4.2 in addition with A1.1, A2, A3.1, A4.1) in Auxiliary winding. In which same turns are added in all 4 poles of Auxiliary winding. So 4 Poles remain in Main winding as well as in Auxiliary winding. No pole difference causing no electrical imbalance between Run and Start winding. Free from imbalance noise in motor.
[0024] In High speed point: Further more number of turns added in all 4 poles of Auxiliary winding. So 4 Poles remain in Main winding as well as in Auxiliary winding. No pole difference causing no electrical imbalance between Run and Start winding. Free from imbalance noise in motor.
[0025] In Concentric winding method same number of turns from all four coil of aux. winding removed or added during speed regulation, no electrical imbalance in both run and aux. winding at low and medium speed and resulting no noise in motor and use only single value capacitor.
[0026] Fig. 2a and 2b illustrate structure of fan blade unit, in accordance with the present subject matter. The TPW fan blade 200 (hereinafter it can be referred as fan blade 200) has a hub 201 and a plurality of blades 202. The hub 201 is provided at center of the fan blade unit 200. The fan blade unit 200 is coupled with rotor part of the single phase concentric winding induction motor. The rotor of the single phase concentric winding induction motor coupled with rear surface of the hub 201. The rotor is being inducted by the stator around. The coupling of the stator and the fan blade unit 200 can be done by means of screw, bolt, and snap lock. The plurality of blades 202 extends away from circumference of the hub to define a circle. Each blade 202 from the plurality of blades 202 has a hub end 202a and a tip end 202b. The hub end 202a is proximal to the hub 201 and the tip end 202b at distal end of the blade. In the present specification, the fan blade unit 200 has five blade leafs. The number of blades in the fan blade unit 200 is not limited to five only it may have three leafs or more than five blade leafs. Each blade from the plurality of blades define a convex shape profile.
[0027] Fig. 3 illustrates variable twist angle, variable thickness, and variable depth of the aerofoil shaped blade with winglet at different cross section points, in accordance with an embodiment of the present subject matter. To illustrate optimized parameters and structure of the present fan blade unit 200, the fan blade unit 200 is divided into three sections EE, FF, and GG at distance 47mm, 112mm, and 178mm from the center of the hub, respectively. Each blade from the plurality of blades 202 has continued twist angle running from the hub end 202a to the tip end 202b. The twist angle decreases non-uniformly from the hub end 202a to the tip end 202b along length of the blade 200. The twist angle is in range 19o to 14o from the hub end 202a to the tip end 202b. Further, depth of the fan blade 202 is in range 2mm to 4.9mm from the hub end 202a to the tip end 202b.
[0028] As shown in the figure 4a, the section EE which is closer to the hub end 202a has highest twist angle 203a in range 17o to 19o, preferably 18.7o. At the section EE, the depth 203b is in range 2mm to 3mm, preferably 2.2mm.
[0029] The section FF has twist angle 204a is in range 15o to 17o, preferably 16.20o. At the section FF, the depth 204b is in range 3mm to 4mm, preferably 4.30mm.
[0030] The section GG has twist angle 205a is in range 14o to 16o, preferably 15. 20o. At the section GG, the depth 205b is in range 4mm to 5mm, preferably 4.5mm.
[0031] Referring to figure 2-4, the blade 202 has variable width which increases from the hub end 202a to the tip end 202b. The blade 202 is wider at the tip end 202b and narrows down towards the hub end 202a. The thickness at hub end is designed to give higher air delivery and to allow blade fitment with the motor shaft and to withstand the blade in static as well as dynamic load without sagging/ breaking.
[0032] Referring to figure 5, each blade from the plurality of blades 202 has lift angle 206 is in range 4o to 6o, preferably 4.5o.
[0033] The fan blade unit 200 defines a circle with radius in range 390 mm to 400 mm, specifically in range 390mm to 395mm. The fan blade unit 200 is made of SAN (Styrene Acrylonitrile) material in single mold processs.
[0034] Figure 6a, 6b, and 6c illustrate table, wall, and pedestal (TPW) fan, in accordance with an embodiment of the present subject matter. In the present TPW fan 300, a single phase concentric winding induction motor 100 and a fan blade unit 200 is mounted. Figure 6a illustrates table fan, figure 6b illustrates wall fan and figure 6c illustrate pedestal fan.
[0035] The present TPW fan with combination of single phase concentric winding induction motor and the fan blade unit provides a novel combination which increases performance of fan with respect to air delivery (in CMM), Air velocity (meters/min), Power input (in watt), noise (in DB). The single phase concentric winding induction motor with the present fan blade unit provides better, more expeditious and economical results as compared with existing TPW fans.
Criteria Normal Speed High Speed Present invention

RPM 1300 2000 1350

Peak Air Velocity Meters/ min 190 255 265

Air Delivery (CMM) 84 95 95

Power Input (Watt) 58 110 80

Noise (dB) from 1 meter of Blade plane 59 67 60

[0036] Although embodiments for the present subject matter have been described in language specific to structural features, it is to be understood that the present subject matter is not necessarily limited to the specific features described. Rather, the specific features and methods are disclosed as embodiments for the present subject matter. Numerous modifications and adaptations of the system/component of the present invention will be apparent to those skilled in the art, and thus it is intended by the appended claims to cover all such modifications and adaptations which fall within the scope of the present subject matter.