Abstract:
According to the invention a method and apparatus relating to a blower that is used in an environment of particle contaminated air, as with a helicopter engine, is disclosed. The blower has a power input, a fan, a power output attaching to the fan, and a clutch disposed between the power input and the power output whereby the power input may be selectively coupled to the power output to move the fan to vent the particle contaminated air. The clutch, which may be electrically, mechanically or hydraulically engaged, is activated by a user, a particle or altitude sensor, or by a full authority digital electronic controller (“FADEC”).

Description:
FIELD OF THE INVENTION 
       [0001]    This invention generally relates to blowers and, particularly, to a blower for use particularly in environments of particle contaminated air. 
       BACKGROUND OF THE INVENTION 
       [0002]    Impeller-type air pumps or blowers are used in many environments and applications. Such a blower conventionally includes a housing defining a pumping chamber or cavity within which an impeller assembly is rotated. The impeller assembly is mounted on shaft that is rotatably journaled within the housing and includes radially projecting blades for drawing air into an inlet of the housing and out through an outlet. 
         [0003]    Blowers are typically used in conjunction with inlet particle separators (“IPS”) in environments of particle contamination. For instance, in aircraft applications, such as with a helicopter, the vehicle may be used over sandy areas, such as deserts. Many known types of IPS are used to minimize engine intake of particle contaminated air to minimize adversely effects in performance or damage to the engines. Blowers exhaust air-laden separated particles from the IPS before the particles can enter the engine. Such blowers typically require power from the helicopter engines to run. 
       SUMMARY OF THE INVENTION 
       [0004]    According to the invention a method and apparatus relating to a blower that is used in an environment of particle contaminated air, as with a helicopter engine, is disclosed. The blower has a power input, a fan, a power output attaching to the fan, and a clutch disposed between the power input and the power output whereby the power input may be selectively coupled to the power output to move the fan to vent the particle contaminated air. 
         [0005]    According further to the invention, the clutch, which may be electrically, mechanically or hydraulically engaged, is activated by a user, a sensor, altitude of the engine, or by a full authority digital electronic controller (“FADEC”). 
         [0006]    Other objects, features and advantages of the invention will be apparent from the following detailed description taken in connection with the accompanying drawing. 
         [0007]    The features of this invention that are believed to be novel are set forth with particularity in the appended claims. The invention, together with its objects and the advantages thereof, may be best understood by reference to the following description taken in conjunction with the accompanying drawings, in which like reference numerals identify like elements in the Figures. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a schematic view of the IPS blower of the invention employing a hydraulically actuated clutch. 
           [0009]      FIG. 2  is a schematic view of the IPS blower of the invention employing a electrically actuated clutch. 
           [0010]      FIG. 3  is a schematic view of the IPS blower of the invention employing a electromechanically actuated clutch. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0011]    Referring to  FIGS. 1-3 , a blower system  10  includes an IPS  15 , a clutch mechanism  20 , a blower assembly  25  and a controller  30 . The blower system  10  is typically attached to an engine  31  (see  FIG. 3 ) that is used with helicopter  34  (see  FIG. 3 ) or other engines that require minimized amount of particulates within the air. 
         [0012]    The IPS  15 , which is shown schematically in  FIGS. 1-3 , could be any prior art mechanisms that separate air streams into a cleaner portion (not shown) for engine use and a not-so-clean portion that is not for engine use that is vented to ambient  32  from an engine  34  (see  FIG. 3 ). The IPS shown communicates the not-so-clean air to the blower assembly  25 . 
         [0013]    The blower assembly  25  comprises a housing  30 , a plurality of bearings  35  attached conventionally to the housing, a hub  40 , a plurality of fan blades  45  that impel the not-so-clean air from the IPS through the housing to ambient, and an impeller shaft  50  driven at a right angle by a bevel gear  55  and supported by the bearings  35  along the impeller shaft length. The fan blades are attached to and arrayed at an appropriate angle in the hub  40  to direct not-so-clean air to ambient  32 . 
         [0014]    Referring now to  FIG. 1 , a first embodiment of a clutch mechanism  20  is shown. The clutch mechanism, which is driven by an engine gear box (not shown) that rotates shaft  22 , comprises; hydraulic fluid  60 , which may be fuel or other liquid, a piston  65  driven by the fluid impelled by a pump (or a solenoid operated pressure signal)  67 , a pivotable rod  70  pushed by the piston about pivot  72 , a rotating throwout bearing  75  pushed by the rod  70 , a plurality of rotating legs  80  pushed by the throwout bearing  75 , a rotating clutch plate  85  pushed by the legs  80  and a fly-wheel  90  that engages the rotating clutch plate  85 . The fly-wheel  90  is fixedly attached to impeller shaft  50 , and contact with the rotating clutch plate thereby causes the fan blades  45  to turn due to the now rotating impeller shaft  50  and draw the not-so-clean air through the housing  30  to ambient  32 . 
         [0015]    Spring  95  acts to pull the legs  80  and clutch plate  85  away from the fly-wheel if hydraulic pressure is removed from the piston  65 . Controller  30  acts to actuate and deactuate hydraulic pump (or a solenoid operated pressure signal)  67 . 
         [0016]    Referring now to  FIG. 2 , a second embodiment of a clutch mechanism  120  is shown. The clutch mechanism  120  which is driven by an engine gear box (not shown) that rotates shaft  122 , comprises; an electric ram  130 , a pivot arm  170  driven by the electric ram, a rotating throwout bearing  175  pushed by the rod  170 , a diaphragm spring  135  flexed by the throwout bearing, a rotating pressure plate  140  pushed by the diaphragm spring  135 , and a rotating clutch plate  185  that is pushed by the pressure plate  140  into contact with a fly-wheel  190 . The fly-wheel  190  is fixedly attached to impeller shaft  50  and contact with the rotating clutch plate  185  causes the fan blades  45  to turn due to the now rotating impeller shaft  50  and draw the not-so-clean air through the housing  30  to ambient  32 . 
         [0017]    Diaphragm spring  135  acts to pull the pressure plate  140  away from clutch plate  185  to disengage the clutch mechanism from the fly-wheel  190  if the electric ram does not urge the pivot arm  170  against throwout bearing  175 . Controller  30  acts to actuate and deactuate electric ram  130 . 
         [0018]    Referring now to  FIG. 3 , a third embodiment of a clutch mechanism  220  is shown. The clutch mechanism, which is driven by an engine gear box (not shown) that rotates shaft  222 , comprises; an electric motor  225 , a throwout bearing  275  driven axially along ramp or ball race or the like  221  (shown schematically) by the electric motor, a plurality of rotating legs  280  pushed by the throwout bearing  275 , a rotating clutch plate  285  pushed by the legs  280  and a fly-wheel  290  that engages the rotating clutch plate. The fly-wheel  290  is fixedly attached to impeller shaft  50 , and contact with the rotating clutch plate  285  thereby causes the fan blades  45  to turn due to the now rotating impeller shaft  50  and draw the not-so-clean air through the housing  30  to ambient  32 . 
         [0019]    Spring  295  acts to pull the legs  280  and clutch plate  285  away from the fly-wheel  290  if the electric motor  225  is turned off. Controller  30  acts to actuate and deactuate electric motor  225 . 
         [0020]    Actuation of the electric motor  225 , pump  67 , and electric ram  130  by controller  30  may occur in several different ways. 
         [0021]    Referring to  FIG. 1 , a particle sensor  300 , as is known in the art, is shown. If the particle sensor detects that levels of particulates in the air are approaching a not-so-clean level, e.g., air that is deemed inappropriate for engine use, the controller  30  will interpret the output of the sensor to actuate the pump  67  to cause the clutch to engage the fan blades  45 , as described hereinabove, to move such air to ambient  32 . One of ordinary skill in the art will recognize that the sensor  300  and controller  30  could also actuate the electric motor  225  and electric ram  130 . The sensor  300  is shown in the IPS and may also be placed in a front of the engine  31 . 
         [0022]    Referring to  FIG. 2 , a pilot or other engine user could observe ambient to determine visually whether the ambient contains an unacceptable level of particulate matter, such as during takeoff, landing or a sand storm, and flip a switch  305  to actuate the electric ram  130  via controller  30 . One of ordinary skill in the art will recognize that the switch  305  and controller  30  could also actuate the electric motor  225  and hydraulic pump  67 . 
         [0023]    Referring to  FIG. 3 , an altimeter  310 , as is known in the art, is shown. If the altimeter senses that the engine is above an altitude where the level of particulates are better than not-so-clean (i.e. above takeoff or landing altitudes or above typical altitudes for sandstorms) for engine use, the controller turns electric motor  225 , and therefore fan blades  45 , off. Similarly if the engine is below such altitudes, the controller turns on electric motor  225  to cause clutch  220  mechanism to engage and rotate fan blades  45  as described hereinabove. One of ordinary skill in the art will recognize that the sensor  300  and controller  30  could also actuate the pump  67  and electric ram  130 . 
         [0024]    Referring to  FIGS. 1-3 , the controller  30  may also be a FADEC under which any of the electric motor  225 , pump  67 , and electric ram  130  may be controlled according to many parameters including altitude, observation and particulate sensing as mentioned hereinabove and other parameters including power requirements (i.e., when the clutch mechanisms mentioned herein are disengaged, the engines have more power and aircraft can obtain more lift), and fuel economy (i.e., when the clutch mechanisms mentioned herein are disengaged, the engines use less power and therefore less fuel to propel an aircraft) and mission requirements (including but not limited to take-off, landing, maneuvering, evasive and high speed requirements, flying range, combat etc.) among others things. 
         [0025]    It will be understood that the invention may be embodied in other specific forms without departing from the spirit or central characteristics thereof. The present examples and embodiments, therefore, are to be considered in all respects as illustrative and not restrictive, and the invention is not to be limited to the details given herein.