Abstract:
A windmill of the vertical axis type having a plurality of circumferentially-spaced rotatably-mounted vanes wherein means are provided for controlling the feathering of the vanes so that, upon feathering they rotate in a direction opposite to that rotation of the windmill assembly, wherein means are provided to assure that the entire assembly heads up into the wind, and wherein means are provided for disengaging of the entire vane assembly when the wind velocity reaches a predetermined value.

Description:
This application is a continuation-in-part of co-pending application Ser. No. 530,830, filed Mar. 3, 1975, now abandoned. 
    
    
     SUMMARY 
     The windmill of the present invention distinguishes over the prior art. Because of these novel features vibration is reduced to a minimum and rotation at excessive speed is precluded. As the vane assembly rotates about a central mast it defines, in plan view, a power side and a feathered side. The vanes are directed downwind on the power side of the mast and are feathered to be propelled upwind as they traverse the downwind arc of the circular path in which the vanes travel. The vanes are caused to feather in a direction counter to the direction of rotation of the vane assembly by means releasing the vanes just prior to their reaching a complete downwind position. Considering the apparatus from above, the vanes rotate from a zero angular position with respect to the direction of the wind progressively to a position in which they are broadside to the direction of the wind and continue to diminish their angular positions to within a few degrees of zero, at which time the vanes are released in response to movement of the cam followers of a cam mechanism. By this arrangement the vanes are feathered in a direction opposite to the direction of rotation of the vane assembly, thereby precluding the deleterious effects of normal backward feathering with consequential vibration and shock resulting from the momentary backward pressure of the wind on the backside of the vane. The cam assembly is rotatably held to a position with respect to the wind direction as to assure the vane release relationship above described by means of a wind directional vane or fin assembly which is also effective in raising the cam assembly to a position in which the cam followers are all effectual simultaneously permitting the vanes to swing freely and the windmill is deactivated. As understood, this latter function is for the purpose of preventing damage to the windmill in the event of high velocity winds. When the wind gusts recede to safe velocity, the fin and cam assemblies lower by gravity and reactivation of the windmill is initiated. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1 is a plan view of the windmill of the invention illustrating the varying positions of the vanes at different phases of rotation of the vane assembly. 
     FIG. 2 is an elevational view of the vane assembly of the windmill made in accordance with the present invention and illustrates a general view of the mechanics of the prefeathering machinery, as viewed from line 3--3 in FIG. 1. 
     FIG. 3 is an enlarged fragmentary elevational view illustrating a cam assembly for unlatching each individual vane as it approaches a predetermined angular position to the direction of the airflow to effect rotation of each individual vane, as illustrated in FIG. 1, in a clockwise direction as the entire assembly rotates in a counterclockwise direction. 
     FIG. 4 is a fragmentary enlarged view of the structure of FIG. 2 illustrating the wind direction vane or fin-vane and the manner in which this wind fin causes the entire assembly to head up into the wind. 
     FIG. 5 is a sectional plan view taken substantially on line 5--5 of FIG. 3. 
     FIG. 6 is an enlarged fragmentary elevational view of a modified form of the present invention illustrating the latching mechanism in conjunction with the hinged end bar of the latch linkage as it is associated with the solenoid. 
     FIG. 7 is fundamentally the same as FIG. 6 except illustrating how the same mechanism in FIG. 6 is adapted to the lower counterpart of FIG. 6 as adaptive to the bottom structure of the windmill. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings, and more particularly to FIGS. 1 and 2, the windmill of the present invention is indicated generally by reference to a vane assembly indicated by numeral 12, mounted for rotation about a vertical axis 14. The curved arrows in FIG. 1 indicate that the vertical assembly is rotating in a counterclockwise direction while the individual vanes feather in a clockwise direction. This is arbitrary and could be clockwise and counterclockwise respectively if desired. 
     FIG. 1 illustrates the windmill of the invention as illustrated from above. At the extremities of each of the arms 18a, 18b, 18c, 18d, 18e, and 18f and their inverted counterpart arms at the bottom are a series of vanes 30a, 30b, 30c, 30d, 30e, and 30f. On each of said vanes is a pivot point 36. The wind fin vane 90 is shown in its constant downwind position, flanked on each side by its lifting ailerons 92. 
     Referring now to FIG. 3 there is illustrated therein an arm 18a, having a vane 30a pivotally connected thereto at pivot point 36. On each of the several vanes is a pivot point 36. As the vane assembly rotates in a counterclockwise direction, the several vanes move sequentially and progressively as illustrated, in a clockwise direction about pivot point 36 starting at 31. The free edge of the vane describes a path illustrated by a dotted line indicated by numeral 37. It will be noted that each vane rotates in a clockwise direction about pivot point 36 while feathering, as the vane assembly rotates in a counterclockwise direction. This is an important feature of this invention since it eliminates vibration and shock which will tend to destroy the vane assembly. In FIG. 2 the vane assembly 12 is illustrated as being mounted on a base 30 containing a journal 22 for reception of the lower end of mast 14. It will be appreciated that the base 30 is fixed to any suitable firm surface and the entire structure is held erect by a plurality of guy wires 10 attached to the outer ends of adjoined trusses 26 which form a common juncture at their centers around journal 24 which receives the upper end of mast 14 on which the entire vane assembly rotates; the lower ends of the guy wires are anchored to the same firm surface as is base 30. 
     Another feature of the present invention provides for latching of the vanes by means of a plurality of latch assemblies 38. Only one such is shown in detail. 
     Each latch assembly includes a radially outwardly extending bar 54 with a latch 38 attached to the outer end by hinge 102. Connected to the inner end of bar 54 is a downwardly extending rod 56 to the bottom of which is connected a radially inwardly extending rod 58. Rod 56 is obviously eliminated in the lower linkage assembly. A rod 60 extends upwardly from the end of rod 58 and to the upper end of rod 60 is secured a cam-follower 62 which follows a contour of the inner cam wall 64 and the outer cam wall 66. See FIG. 5 in conjunction with FIG. 3. The cam assembly as indicated generally by reference numeral 68 includes a top cover 72, an inner wall 64 and an outer wall 66 cooperating to form a conical track 70. In normal operation, the bar 38 of the latch assembly extends radially outwardly in front of the corner projections of the vane, 48 and 50 at the top and the bottom of the vane respectively which is part of the inner edge of each of the vanes and prevents rotation of the vanes before feathering time. Each bar 54 and 38 is slidably received in an apertured support 55 and 53 respectively, the latter affording both horizontal and vertical movement of latch bar 38. 
     The entire latch assembly is pulled radially inwardly in response to centripetal movement of the cam-followers 62 in the cam track 70 to move the bar 54 and the attached latch 38 inwardly as viewed in FIG. 3, occurring when said cam followers pass lobe 96 beginning at point 110 which comprises part of the outer cam wall 66. 
     As above described, the vanes advance to within a few degrees of zero angularity with the direction of downwind at which time the cam actuated latch assembly is activated, which allows the free inner edge of the vane to blow on through past the withdrawn latch 38 and begin its feathering in a smooth swivel turn as it traverses the downwind arc of its circular travel. It will be appreciated that the second cam assembly at the bottom of the vane assembly is synchronized with the cam assembly at the top for rotation around the shaft 14, by the rigidity of the fin-vane 90 attached to each cam assembly 68 at sleeves 74 by clamping. The sleeves 74 are component parts of the cam assemblies. The top sleeve extends inferiorly from the top cam assembly but the bottom cam assembly has its sleeve extending superiorly; the difference is necessitated to accommodate fastening both assemblies to the wind direction vane 90 or fin vane as it may be called. 
     It is thus apparent that both cam assemblies will rotate about the shaft 14 in unison. This facilitates unlatching both the top and the bottom of the vanes at the same moment. Furthermore, means are provided for elevating the entire wind-direction-fin-vane 90 and cam assemblies in the event that the wind speed exceeds a predetermined velocity. This means includes ailerons 92 pivotally connected to the fin 90 so as to rise when strong wind gusts occur, in opposition to spring 94, to raise the assemblies so that the cam followers 62 ride below the cam lobe 96, in the lower and smaller diameter section of cam track 70. See FIG. 3. Thus, all latch linkage is pulled inward letting all vanes feather and the windmill ceases to rotate. 
     The latch 38 may, if desired, be electronically operated, as by solenoid 100 to move the outer end of the said hinged latch 38 upwardly to the elevated position illustrated in dot-and-dash lines in FIGS. 3, 6, and 7. It will be understood that the solenoid would be energized by activation of a cam-associated switch mechanism (not shown) to release each vane at the desired moment. Elementary circuitry is provided to the solenoids from an electrical source of power (not illustrated). 
     The release point for the releasing activation of latches 38 may be adjusted by rotating the clamping assemblies 104 of the wind fin vane 90 about sleeves 74 when bolts 16 are loosened. 
     It will be noted that the cam track 70 has a lobe 96 and a curved corresponding section 98 in confronting relation to element 96 so as to guide the cam followers and effect the release cycle. Feathering of the vane begins when the associated follower 62 reaches the lobe 96 at point 110, the latch 38 is activated and drawn radially inwardly, thus precluding normal backward feathering. When the latches 38 are clear of the inward projections of the vanes, 48 and 50, the vane is released and allowed to feather clockwise. It will be seen, therefore, the pressure of the wind continues on the power side of the vane even through the control phase of its feathering which is the first 90 degrees of its swivel. The consequent pressure on the vane in the first 90 degrees of the feathering process beneficially adds continuing power to said vane for a brief period of time, effecting continued torque to the forward rotation of the windmill. However, if the same windmill, although functional, is allowed to feather backwardly, uncontrolled, with latches not withdrawn inwardly, a reverse power is monentarily applied to the vane in its backward feathering and a resultant jerk on the entire windmill ensues, giving rise to destructive and severe vibration. Since the feathering process attains enough speed in the first half of its 180 degrees swivel, pressure and backlash on the apparatus is negligible in the second half. 
     As the vane completes its feathering, the air cushioning of the windstream, limited in velocity to the windmill&#39;s accepted tolerance predetermined by the adjusted lifting capacity of ailerons 92, obviates any necessity of any kind of shock absorbers.