Patent Publication Number: US-3879151-A

Title: Toroidal fan

Description:
United States Patent 1 Majewicz Apr. 22, 1975 1 TOROIDAL FAN [76] lnventor: Wlodzimierz I. Majewicz, 226 Fern Ave., Toronto, Ontario, Canada, M6R 1K4 221 Filed: Feb. 6, 1974 21 Appl. No.: 440,118  
 [52] US. Cl. 415/76; 416/240; 415/214; 115/2; 415/141 [51] Int. Cl. F01d l/36 [58] Field of Search 415/90, 76, 214, 141, 140, 415/129, 70; 416/240, 66; 259/6; 100/158 C; 115/2;418/152, 153  
 Primary Examiner-Henry F. Raduazo ABSTRACT A rotor is provided for use in moving fluids by immersing the rotor in the fluid. The rotor includes first and second end plates having means for coupling the end plates to respective drive and driven spindles with the axes of the spindles in a common plane. A plurality of flexible annular elements are coupled to one another at a plurality of locations about the elements with these locations spaced substantially equally around the annular element. End ones of the elements are coupled to the respective end plates such that with the spindles on a common axis, the elements are also concentric about this axis. Further, upon moving the end plates angularly with respect to one another, radial cavities are formed between the said locations. These cavities vary in size as the rotor turns, the cavities being largest where the end plates are farthest apart. these end plates extend unbroken across the said end ones of the elements so that in use the fluid does not move through the end plates axially into the rotor. Embodiment of structures incorporating the rotor are also described.  
 4 Claims, 6 Drawing Figures PATENTEU M22515 sum 3 0F 3 FIG. 6  
 TOROIDAL FAN This invention relates to devices for moving fluids and more particularly to a rotor used in such devices.  
  Although the invention will be described primarily for use&#39;with air fans. the scope of the invention includes uses with liquids also. Consequently the term fluid&#34; will be used for all substances which can be used with the invention.  
  Air fans presently available fall into two types namely propeller or air screw types, and types which include an impeller or rotor and a casing. The propeller suffers from disadvantages such as safety and inefficiency due to losses at the tips of the propeller blades. Although the impeller type is more efficient and safer, the impeller and casing combination is expensive. Accordingly, many attempts have been made to simplify both the impeller and the casing in order to reduce the cost of this combination.  
  A particularly interesting example of prior art fans is shown in US. Pat. No. 2,582,413 to J. M. Clark. This patent shows a casing containing an impeller made up of annular elements connected along radial joints to define radial cavitites. The fluid enters the impeller at the centre and moves radially before being collected and directed by the casing. The impeller is arranged so that the radial cavities open and close as the impeller rotates to enhance the centrifugal effects of the impeller as the fluid moves radially. Although the present invention appears to include a somewhat similar impeller, the present impeller is entirely different in operation as will become apparent.  
  In a particular preferred embodiment of the present invention, a rotor is provided for use in moving fluids by immersing the rotor in the fluid. The rotor includes first and second end plates having means for coupling the end plates to respective drive and driven spindles with the axes of the spindles in a common plane. A plurality of flexible annular elements are coupled to one another at a plurality of locations about the elements with these locations spaced substantially equally around the annular element. End ones of the elements are coupled to the respective end plates such that with the spindles on a common axis, the elements are also concentric about this axis. Further. upon moving the end plates angularly with respect to one another, radial cavities are formed between the said locations. These cavities vary in size as the rotor turns, the cavities being largest where the end plates are farthest apart. These end plates extend unbroken across the said end ones of the elements so that in use the fluid does not move through the end plates axially into the rotor.  
  The invention will be better understood with reference to the drawings, in which:  
  FIG. I is a perspective view ofa fan incorporating the invention;  
  FIG. 2 is a partially exploded perspective view of a portion of a rotor used in the fan;  
 FIG. 3 is a top view of the rotor as seen in FIG. 1;  
  FIG. 4 is a diagrammatic end view of the rotor shown in FIG. 3 and indicating the movement of air as the rotor rotates;  
  FIG. 5 is a diagrammatic side view of another embodiment of the invention in use as an outboard motor; and  
  FIG. 6 is a diagrammatic side view of a further embodiment of the invention.  
  A simple embodiment of the present invention is illustrated in FIGS. 1 and 2 to which reference is now made. As seen in FIG. 1., an electric motor 20 or other suitable prime mover is coupled by a drive spindle 22 to a rotor 24. This rotor is rotatably coupled at its outer end to an adjustable rotor support 26 which is attached by screws 28 (one of which is shown) to a front face of the motor 20. The support 26 permits the rotor to be adjusted between a position in which the drive spindle 22 is in line with a driven spindle 30 at an outer end of the rotor and a position in which the axes of these spindles are at about to one another. The axes remain in a common plane during this adjustment.  
  Before describing the support 26 in detail, the construction of the rotor 24 will first be described with reference initially to FIG. 2.  
  The rotor 24 consists ofa circular inner end plate 32, a plurality of annular grub elements 34, and an outer end plate 36 (FIG. 1 The end plates 32, 36 are preferably similar in shape. As seen with reference to plate 32, each end plate has an external boss 38 concentric with a circular disc-like main portion 40 and internal radial ribs 42 arranged concentrically with respect to the axis of the boss 38 and portion 40. The boss 38 is adapted to receive an end portion of the motor drive spindle 22 and a grub screw 44 is provided in the boss to lock the plate 38 to the spindle 22. Similarly, a grup screw 44&#39; is provided in boss 38&#39; of end plate 36 for retaining an inner end portion of drive spindle 30 in the boss 38&#39;.  
  As seen in FIG. 2, the elements 34 arev annular and those elements nearer to the plate 32 locate on the ribs 42. Similar location is provided by plate 36 for those elements immediately adjacent to the plate 36. The ribs 42 are not essential in all applications, but it will become evident that these ribs limit the degree of stress created in the elements immediately adjacent the plates 32, 36 when the rotor is adjusted to create a larger angle between the axis of the drive spindle 22 and the driven spindle 30.  
  Each particular element 34 is of any suitable material having the design flexibility and strength to transmit drive from an adjacent element on the motor side of the element in question to an element on the opposite side of this particular element. The strength criteria will be considered in more detail later in this description.  
  As seen in FIG. 2, each element 34 has four first attachment areas 44 extending radially and equally spaced about the element on one side thereof; and four second attachment areas 46 on the other side thereof. The areas 46 are spaced equally about the element intermediate the areas 44 on the other side of the element. The areas 44, 46 are used to attach the elements to adjacent elements by gluing, binding, or other suitable means depending upon the type of material used for the elements. As a result, radial cavities 48 are formed between each adjacent pair of elements 34 when the elements are pulled away from one another.  
  It will be evident that the rotor construction permits the end plates 32, 36 to be moved angularly relative to one another so that in a position such as that seen in FIG. 1, the radial cavities 48 on one side of the rotor 24 will be closed whereas those on a diametrically opposite side of the rotor will be wide open. The opening in the centre of each element 34 is primarily to permit adequate flexibility of the rotor. There is substantially no useful airflow in this portion of the rotor because the ends of the rotor are substantially sealed by the end plates 32, 36. This is unlike prior art devices in which air is inspired at the centres of the elements and caused to move outwardly by a combination of centrifugal force and a squeezing action as the cavities such as cavities 48) are closed. Such a prior art device is illustrated in the previously mentioned US Pat. No. 2.582.413 to Clark. The action of the present rotor 24 will be described subsequently with reference to FIGS. 3 and 4.  
  Returning now to FIG. 1, the rotor support 26 consists essentially ofa first member 50 attached by screws 28 to the motor and a second member 52 which is pivotally attached to the member 50 by a bolt 54 and cooperating wing nut 56. The axis of the bolt, (and also the axis about which the second element 52 rotates relative to the first element 50) is outside the rotor as indicated at 58 in FIG. 3. The shapes of the members 50, 52 are unimportant although the axis 58 should lie symmetrically relative to the end plates 32, 36 to avoid creating stresses in the elements 34 as the rotor is adjusted.  
  The rotor support member 52 includes a general bearing 60 carrying the spindle 30 and the spindle is retained in the bearing by a collar 62 attached by a suitable set screw to this spindle.  
  Reference is now made to FIGS. 3 and 4 to describe the operation of the rotor 24. As seen in FIG. 3, the radial cavities 48 are substantially closed where the peripheries of the end plates 32, 36 are nearest one another and are at a position of maximum opening where these plates are most remote from one another. Consequently as the rotor makes one revolution. air is expelled from the cavities radially as the open cavities are closed and at the same time air moves radially inwards into other cavities as these cavities open. There is a lag as the air moves, and also, due to the speed of rotation, the exiting air is not truly radial as it leaves the rotor. The general air movement is indicated in FIG. 5 which is an end view of the rotor in the FIG. 4 position.  
  It will now be appreciated that the output from the rotor is directional without the need for a casing and this is achieved by preventing air flow through the middle of the rotor from the ends of the rotor. The end plates prevent this axial flow and consequently there is no centrifugal output from the rotor in the parts of the rotation where air is entering the radial cavities from outside the rotor. This resulting radial movement of air inwards means that there is outward movement of air only in the restricted portion of the rotation indicated in FIG. 4. The volume of air moved by the fan can be changed from substantially zero to a maximum by moving the driven spindle from a position in which the spindle is in alignment with the drive spindle to a position in which the spindles are about 90 to one another. Of course this movement depends upon the number of annular elements used in the rotor and also the type of material used to make the elements.  
  Each of the elements 34 can be of any suitable material. Soft materials such as cloth can be used although this material will transmit torque to accelerate the rotor only when the spindles 22, 30 are in alignment with one another. There is then no fan effect because the cavities are not opening and closing. However, a fan action according to the invention can be achieved with this material by accelerating the rotor up to speed with the spindles aligned and then moving the driven spindle 30 angularly by adjusting the rotor support 26.  
  Successful fans have been made using quite thin cardboard for the elements 34. Such fans can be rotated and stopped with the rotor in a position. In general the material for the elements should be light, reasonably stiff, and capable of being attached to adjacent elements at the attachment areas 44, 46 seen in FIG. 2. The rotor could also be ofa moulded plastic construction provided that the material used for moulding has the necessary flexibility.  
  When a fan is in use, the rotor can be touched without injury. This is because the rotor resembles a curved cylinder when it is running and presents a relatively smooth surface as it rotates. The rotor is therefore inherently safe for use without shielding, provided of course that care is taken in construction to ensure that edges of the elements 34 are not rough or sharp.  
  It has also been found that the elements 34 can be attached to one another at one or more attachment areas 44, 46. However it is preferable to use two or more such areas on each side of an element 34.  
  Although the rotor has been described for use in a fan, the rotor can also be used in various fluids includ ing water. Either to move these fluids or to propel ob jects such as boats through the fluid. As seen in FIG. 5 the rotor 64 is mounted in a rotor support 66 attached to a drive spindle 68 from a prime mover 70. This prime mover can be of any type and is shown diagrammatically attached to the stern of a boat 72.  
  The rotor support 66 and rotor 64 are submerged and an outer member 74 of the support 66 projects beyond a pivotal connection to an inner member 76 for pivotal connection to an end of a connecting element 78. This latter pivotal connection is about a horizontal axis and a similar connection at the other end of the element 78 connects the element to an end of a directional control lever 80. This lever projects into the boat for manual operation and is pivotally mounted in a trunnion 82 which is in turn coupled to the prime mover for rotation about the axis of rotation of the drive spindle 68. Consequently the lever can be operated angularly in a horizontal plane to move the rotor support 66 and hence the rotor 64 about the axis of the drive spindle 68 to change the direction of the boat. Also, the lever 80 can be moved vertically to move the member 74 angularly relative to the member 76 to thereby open or close the rotor 64 whereby the output of the rotor is varied to change the speed of the boat.  
  The present invention provides an outboard drive of the type commonly referred to as an outboard motor in which the motor does not rotate when the direction of the boat is changed. Consequently, the motor does not require a cradle to permit it to turn relative to the boat and the mechanism associated with the rotor 64 can be relatively light. Further, the rotor is of the type which will tend to bounce off obstructions without damage whereas the normal propeller tends to shatter if it comes into contact with a solid object. Yet another advantage is that the motor can run at constant speed and the output can be varied by changing the angle between the drive and driven spindles associated with the rotor. This is particulary advantageous in the next embodiment which is shown in FIG. 6.  
  As seen in FIG. 6 an air cushion vehicle 84 has a fan 86 attached to its rear deck. The vehicle 84 is shown diagrammatically and consequently the structure used to develop lift is not shown.  
  The fan 86 can be rotated by a control structure 88 to change the direction of the vehicle 84 and a rotor 90 can be opened or closed by the structure 88 to vary the thrust developed by the rotor 90. Consequently if a constant speed motor is used to drive the rotor 90 the speed and direction of the vehicle 84 can be varied simply by adjusting the opening of the rotor and the orientation of the rotor about a vertical axis.  
  It will now be evident that the rotor and the fan previously described can be incorporated into many structures. The rotor can be used either to move fluid past the structure as in the case of a simple stationary fan, or to move the structure through the fluid as in the case of a boat using the rotor in water.  
 What I claim as my invention is:  
  l. A rotor for use in moving a fluid with the rotor immersed in the fluid, the rotor comprising: first and second unperforated end plates including means adapted to couple the end plates to respective drive and driven spindles; and a plurality of flexible annular elements coupled to one another at a plurality of locations about these elements, there being a least two such locations where each one of the elements is attached to an adjacent element, the spacings between each location and adjacent locations on the other side of the element being substantially the same for each location, and end ones of the elements being coupled to the respective end plates such that with the spindles on a common axis the elements are also concentric about this axis and upon moving the end plates angularly with respect to one another, radial cavities are formed between said locations, said cavities varying in size as the rotor is turned and the cavities being largest where the end plates are farthest apart, the end plates extending unbroken across the said end ones of the elements so that in use the fluid does not move through the end plates axially into the rotor.  
  2. A fan for moving fluid, the fan comprising: a rotor having first and second unperforated end plates and a plurality of flexible annular elements coupled to one another at a plurality of locations about the elements and end ones of the elements being coupled to the respective end plates so that upon moving one of the end plates angularly with respect to the other end plate, radial cavities are formed between said locations, said cavities varying in size as the rotor is turned and the cavities being largest where the end plates are spaced farthest from one another;  
 a motor coupled to the first end plate to drive the rotor;  
 a rotor support coupled to the motor and to the second end plate to support this end plate for rotation of the rotor, the rotor support being adapted to permit angular adjustment of the second end plate about an axis positioned symmetrically with respect to the end plates, the axis being transverse with respect to the axis of rotation of the rotor and spaced from this axis of rotation by an amount greater than the radial extent of the elements, whereby upon moving the second end plate angularly from a position in which the end plates are parallel, the cavities open where the end plates are remote from one another and close where the end plates are nearer one another to move the fluid.  
 3. A rotor for use in moving a fluid with the rotor immersed in the fluid, the rotor comprising: a plurality of flexible annular elements coupled to one another at a plurality of locations about these elements, there being at least two such locations where each one of the elements is attached to an adjacent element, the spacings between each location and adjacent locations on the other side of the element being substantially the same for each location; and means coupled to end ones of the elements to prevent fluid flow axially inside the annular elements; and means adapted to be coupled to the end means to support the rotor for rotation with the spindles on a common axis, the elements being movable between a position in which the elements are concentric about this axis and a position in which the elements are generally positioned angularly with respect to one another to form radial cavities between said locations, said cavities varying in size as the rotor is turned and the cavities being largest where the elements are farthest apart from one another so that fluid is made to move by rotating the rotor.  
 4. Drive means for a boat and the like the drive means including a fan comprising:  
 a rotor having first and second unperforated end plates and a plurality of flexible annular elements coupled to one another at a plurality of locations about the elements and end ones of the elements being coupled to the respective end plates so that upon moving one of the end plates angularly with respect to the other end plate, radial cavities are formed between said locations, said cavities varying in size as the rotor is turned and the cavities being largest where the end plates are spaced farthest from one another;  
 a motor coupled to the first end plate to drive the rotor;  
 a rotor support coupled to the motor and to the second end plate to support this end plate for rotation of the rotor, the rotor support being adapted to permit angular adjustment of the second end plate about an axis positioned symmetrically with respect to the end plates, the axis being transverse with respect to the axis of rotation by an amount greater than the radial extent of the elements, whereby upon moving the second end plate angularly from a position in which the end plates are parallel, the cavities open where the end plates are remote from one another and close where the end plates are nearer one another to move the fluid; and  
 the drive means further comprising means coupled to the rotor support for selectively rotating the support about an axis of rotation of the first end plate to change the direction of the thrust from the fan, and for adjusting the rotor support to cause the sec ond end plate to move about said transverse axis to change the thrust from the fan.