US544228A - Windmill - Google Patents

Windmill Download PDF

Info

Publication number
US544228A
US544228A US544228DA US544228A US 544228 A US544228 A US 544228A US 544228D A US544228D A US 544228DA US 544228 A US544228 A US 544228A
Authority
US
United States
Prior art keywords
wind
vane
shaft
windmill
tower
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
Publication date
Application granted granted Critical
Publication of US544228A publication Critical patent/US544228A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03DWIND MOTORS
    • F03D3/00Wind motors with rotation axis substantially perpendicular to the air flow entering the rotor 
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03DWIND MOTORS
    • F03D7/00Controlling wind motors 
    • F03D7/02Controlling wind motors  the wind motors having rotation axis substantially parallel to the air flow entering the rotor
    • F03D7/0204Controlling wind motors  the wind motors having rotation axis substantially parallel to the air flow entering the rotor for orientation in relation to wind direction
    • F03D7/0208Orientating out of wind
    • F03D7/0212Orientating out of wind the rotating axis remaining horizontal
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00Energy generation through renewable energy sources
    • Y02E10/70Wind energy
    • Y02E10/72Wind turbines with rotation axis in wind direction
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00Energy generation through renewable energy sources
    • Y02E10/70Wind energy
    • Y02E10/74Wind turbines with rotation axis perpendicular to the wind direction

Definitions

  • the object of my invention is to provide a windmill adapted to drive light farm or other machinery without veering around out of the wind when crowded with work, but which will continue to give its full power regardless of load even in a gale; also to provide a horizontal windmill, which will automatically vary the sail area exposed to the wind in proportion to the strength of the wind; and further to provide a reliable, convenient, and economical means for communicating power from the windmill to various machines located at different distances therefrom.
  • Figure 1 is a side elevation with upper portion of tower, showing the windmill in workingposition by the full lines.
  • Fig. 2 is a vertical fractional section, on enlarged scale, through center of.
  • FIG. 3 is a similar enlarged section showing position of principal parts when thrown out of the wind.
  • I Fig. 4 is an elevation of principal parts at right angles to position shown in Figs. 2 and 3. view of entire windmill.
  • Fig. 6 is a side elevation of windmill and tower, showing mode of transmitting motion to different machines.
  • the vane A is carried on the rectangular.
  • the counterbalance-weight A is attached to a bracket suspended from the front or windward end of the vane -frame a a3, and is adapted to hold the vane-frame in a horizontal position.
  • Each of the sails'D has passed through its center a vertical shaft d, which is journaled in the extremities of the spider-arms E E at- Fig. 5 is a plan tached to the hubs E E on the main vertical shaft E
  • the shaft E is journaled upon the vane-frame a a at e and 6
  • Attached to the sails D are sprocket-wheels d, connected together by the chain F, which also runs over the sprocket-wheel f, which is rigidly attached to the vane-frame a at e where it forms the lower bearing for the main shaft E whichit encircles.
  • the tower-shaft G is a vertical shaft rotating in the center of the hollow mast B, and journaled upon it at 1), Its lower end is journaled upon the tower at g. It is connected to the main shaft E by the links H H H which form a universal coupling, which permits the main shaft E to be inclined atan angle with the vertical tower-shaft G..
  • the link H is rigidly attached to the end of the tower-shaft G and the link H to the end of the main shaft E in the same manner, while the'ring H loosely engages both the links H and H I
  • the tower-shaft G is provided with abevel gear-wheel g, which meshes with another bevel gear-wheel J on the end of the horizontal jack-shaft j.
  • the bevel gearJ is provided with a crank-pinj to which the pump-rodj is connected.
  • the horizontaljack-shaft j extends a considerable distance beyond the side of the tower and carries at its extremity a grooved pulley K.
  • K is a similar grooved pulley attached to the machine tobe driven, and K is a grooved tightener-pulley with counterweight is attached. It hangs upon one loop of the rope or cable k, which runs in the grooves of the pulleys K K.
  • the lower portion of the hollow mast B is slotted, as at 5 It is encircled at this point by the sliding collar L, which is connected by means of the cord, chain, or cable Z, which passes through the slot 1) inside the hollow mast B, and over the sheave b to the vaneframe o to which it is attached at l.
  • the sliding collar L which is connected by means of the cord, chain, or cable Z, which passes through the slot 1) inside the hollow mast B, and over the sheave b to the vaneframe o to which it is attached at l.
  • shifter-fork L engages the groove in the sliding collar L, and is attached to a vertical rod U, which slides in guides L L upon the tower.
  • L is a rod, rope, or other means for extending the rod L so as to operate it from the ground to throw the windmill out of the wind.
  • the letter M indicates a dash-pot attached to the weight-braces a of the vane-frame.
  • the plunger m fits loosely in the dash-pot, as indicated by the dotted lines in Fig. 1, and is rigidly attached to the mast B at m.
  • a is attached to the vane-frame 01, a is attached a fulcrum-piece a, which is connected to the mast-head b by the pivot-bolts Z) Z). Both the fulcrum-piece a and the mast-head I) are provided with weather-guards (1 IF.
  • One of the sails D is provided with two SPI'OCket-WllQBlS d d, and all the others have but one.
  • two separate chains may be used, one of them connecting the small sprocketf to the upper sail-sprocket (1, while the other passes around and engages the sail-sprockets d d d (Z 61 and the lower sail-sprocket (1' only.
  • the chain F holds the sails D, D D D D and D in the positions shown in Fig. 5, that of D being in line with the spider arm or spoke E and atright angles to the vaneframe a a and also to the direction of the wind, as shown by the arrows N. It also holds the sail D at an angle of thirty degrees to the spider-arm E and sixty degrees to the vane-frame, I) at an angle of sixty degrees to the spider-arm E and thirty degrees to the vane-frame, D at right angles to the spider-arm and parallel with the vane-frame and the direction of the wind, D at an angle of sixty degrees to the spider-arm and thirty degrees to vane-frame, and D thirty degrees to spider-arm and sixty degrees to vane-frame.
  • the weight A is heavy enough to hold the vane-frame a a horizontal and the shaft E and sails D vertical in moderate to stiff winds. However, as the force of the wind increases and the pressure on the sails becomes great enough to overcome the resistance of the weight A the forward or windward end of the vane-frame a a rises and the vane Adescends, thereby inclining the main shaft E and the sails D from the vertical, so as to spill the surplus wind over the top of the sails.
  • the dash-pot M forms a cushioned stop, against which the weight A holds the mill while at work and obviates the jar that would otherwise be destructive when the windmill rights up after a heavy gust of wind has passed by.
  • the vane-frame is swung down by the wind against the stop m on the mast l3, opposite to the dash-pot M, in which position the sails D present only their bottom edges to the wind, thus reducing the resistance to the wind to a minimum.
  • the bevel gear J is provided with a crank pin 7' to which the pump-rod 3' may be connected when the pumpis located beneath the windmill.
  • the windmill may be located high up on the bluff or embankment, where a steady wind-pressure is available, and the pump may be placed at the waters edge.
  • the windmill is of incalculable value for irrigation purposes, for many of our Western rivers, located in sections where irrigation is necessary, are apparently dry when water is most needed,
  • a wind motor the combination of a vane connected by horizontal pivots to a hollow vertical mast adapted to turn with the vane, a wind-wheel rotating a shaft j ournaled upon said vane, a counter balance weight adapted to hold the wind-wheel shaft vertical in ordinary winds, and a universal coupling communicating motion to a vertical power shaft rotating within the hollow mast, substantially as described.
  • a wind motor In a wind motor the combination of a vane pivotally connected with a hollow vertical mast adapted to be turned thereby, a windwheel rotating a shaft journaled upon said vane, a weight suspended from the windward end of the vane, a chain or cable attached to the leeward end of the vane and extending through the hollow mast, and a slot in the lower portion thereof to a sliding collar, a shifter fork engaging a groove in the sliding collar, and means for drawing it and the sliding collar downward to incline the wind-wheel and shaft from the vertical, substantially as and for the purpose described.
  • a vane pivotally connected to a hollow vertical mast adapted to be turned thereby, a windwheel rotating a shaft'journaled upon the vane, a ring or link rigidly attached to one end thereof, a vertical power shaft rotating within the hollow mast, a ring or link rigidly attached to the upper end thereof, and a loose ring engaging the-rigid rings upon the said. shafts, substantially as and for the purpose described.
  • a vane connected by horizontal pivots to a vertical mast adapted to be turned thereby, a wind-wheel rotating a vertical shaft journaled upon the vane, a weight attached to a bracket suspended from the windward end of the vane, a dash-pot attached to said bracket, and a plunger attached to the vertical mast adapted to fit into the dash-pot and form a cushioned stop against which the vane is held in ordinary winds, substantially as described.

Description

(No Model. 3 SheetsSheet 2.
' H. S. HOPPER.
WIND'MILL.
No. 544,228. Patented Aug. 6, 18-95.
[N VEJV'TOR.
WITN
(No Model.) 3 Sheets-Sheet 3."
H. s. HOPPER.
WINDMILL. No. 544,228. Patented Aug. 6, 1895.
1 ing position.
NI'TED STATES PATENT ()rrrcs.
HENRY S. HOPPER, OF DETROIT, MICHIGAN.
WINDMILL.
SPECIFICATION forming part of Letters Patent No. 544,228, dated August 6, 1895.
I Application filed June 16,1894. Serial No. 514,792. (No model.)
To all whom it may concern:
Be it known that I, HENRY S. HOPPER, a citi- "zen of the United States, residing at Detroit, in the county of Wayne and State of Michigan, have invented new and useful Improvements in Windmills, of which the following is a specification.
The object of my invention is to provide a windmill adapted to drive light farm or other machinery without veering around out of the wind when crowded with work, but which will continue to give its full power regardless of load even in a gale; also to provide a horizontal windmill, which will automatically vary the sail area exposed to the wind in proportion to the strength of the wind; and further to provide a reliable, convenient, and economical means for communicating power from the windmill to various machines located at different distances therefrom.
In the drawings, Figure 1 is a side elevation with upper portion of tower, showing the windmill in workingposition by the full lines.
The dotted lines show its position when out of the wind. Fig. 2 is a vertical fractional section, on enlarged scale, through center of.
shaft and sails and in line with the vane, showing principal parts in detail and in work- Fig. 3 is a similar enlarged section showing position of principal parts when thrown out of the wind. I Fig. 4 is an elevation of principal parts at right angles to position shown in Figs. 2 and 3. view of entire windmill. Fig. 6 is a side elevation of windmill and tower, showing mode of transmitting motion to different machines.
The principal features of my invention are as follows: 1
The vane A is carried on the rectangular.
frame a a a which is connected at b by horizontal pivots to the top of a hollow vertical mast B, which is journaled upon the top of the tower O at c 0, so as to be turned by the vane A as the direction of the wind changes. The counterbalance-weight A is attached to a bracket suspended from the front or windward end of the vane -frame a a3, and is adapted to hold the vane-frame in a horizontal position.
Each of the sails'D has passed through its center a vertical shaft d, which is journaled in the extremities of the spider-arms E E at- Fig. 5 is a plan tached to the hubs E E on the main vertical shaft E The shaft E is journaled upon the vane-frame a a at e and 6 Attached to the sails D are sprocket-wheels d, connected together by the chain F, which also runs over the sprocket-wheel f, which is rigidly attached to the vane-frame a at e where it forms the lower bearing for the main shaft E whichit encircles.
G is a vertical shaft rotating in the center of the hollow mast B, and journaled upon it at 1), Its lower end is journaled upon the tower at g. It is connected to the main shaft E by the links H H H which form a universal coupling, which permits the main shaft E to be inclined atan angle with the vertical tower-shaft G.. In the universal coupling the link H is rigidly attached to the end of the tower-shaft G and the link H to the end of the main shaft E in the same manner, while the'ring H loosely engages both the links H and H I The tower-shaft G is provided with abevel gear-wheel g, which meshes with another bevel gear-wheel J on the end of the horizontal jack-shaft j. The bevel gearJ is provided with a crank-pinj to which the pump-rodj is connected. The horizontaljack-shaft j extends a considerable distance beyond the side of the tower and carries at its extremity a grooved pulley K. K is a similar grooved pulley attached to the machine tobe driven, and K is a grooved tightener-pulley with counterweight is attached. It hangs upon one loop of the rope or cable k, which runs in the grooves of the pulleys K K. I
The lower portion of the hollow mast B is slotted, as at 5 It is encircled at this point by the sliding collar L, which is connected by means of the cord, chain, or cable Z, which passes through the slot 1) inside the hollow mast B, and over the sheave b to the vaneframe o to which it is attached at l. The
shifter-fork L engages the groove in the sliding collar L, and is attached to a vertical rod U, which slides in guides L L upon the tower. L is a rod, rope, or other means for extending the rod L so as to operate it from the ground to throw the windmill out of the wind.
The letter M indicates a dash-pot attached to the weight-braces a of the vane-frame.
The plunger m fits loosely in the dash-pot, as indicated by the dotted lines in Fig. 1, and is rigidly attached to the mast B at m. To the vane-frame 01, a is attached a fulcrum-piece a, which is connected to the mast-head b by the pivot-bolts Z) Z). Both the fulcrum-piece a and the mast-head I) are provided with weather-guards (1 IF.
One of the sails D is provided with two SPI'OCket-WllQBlS d d, and all the others have but one. I prefer to pass one continuous chain F around allthe sprocket-wheels. That is, commencing with the chain F, about the small sprocket-wheel f, connect it with and around the upper sprocket-wheel d, thence around the outside of the said sprockets d d (Z Cl, and (Z in succession to and around the lower sail-sprocket d, where it is connected to the other end of the chain F from the small sprocket f. However, two separate chains may be used, one of them connecting the small sprocketf to the upper sail-sprocket (1, while the other passes around and engages the sail-sprockets d d d (Z 61 and the lower sail-sprocket (1' only.
The chain F holds the sails D, D D D D and D in the positions shown in Fig. 5, that of D being in line with the spider arm or spoke E and atright angles to the vaneframe a a and also to the direction of the wind, as shown by the arrows N. It also holds the sail D at an angle of thirty degrees to the spider-arm E and sixty degrees to the vane-frame, I) at an angle of sixty degrees to the spider-arm E and thirty degrees to the vane-frame, D at right angles to the spider-arm and parallel with the vane-frame and the direction of the wind, D at an angle of sixty degrees to the spider-arm and thirty degrees to vane-frame, and D thirty degrees to spider-arm and sixty degrees to vane-frame.
Itis evident that as the sails D D,and D stand at greater angles to the wind than the sails D D", and D the wind-wheel will revolve in the direction indicated by the arrows O, and as the small sprocketf is one-half the diameter of the sprockets d, and as itis held stationary by the vane A, the chain F will draw the sails into new positions, D taking the position of D when it has made one-sixth of a revolution and that of D at one-third of a revolution, and so on around, making one half a revolution about its own axis (1 while it is making a complete revolution about the main shaft E returning to its original position D',with its opposite side to the wind. In other words, the sails take exactly the same positions that the sails of a vessel would take in sailing around a circle.
The weight A is heavy enough to hold the vane-frame a a horizontal and the shaft E and sails D vertical in moderate to stiff winds. However, as the force of the wind increases and the pressure on the sails becomes great enough to overcome the resistance of the weight A the forward or windward end of the vane-frame a a rises and the vane Adescends, thereby inclining the main shaft E and the sails D from the vertical, so as to spill the surplus wind over the top of the sails. As the weight A is located at some distance below the fulcrum b of the vaneframe, it is evident that its resisting effect increases as the wind-wheel is inclined farther from a vertical position by the pressure of the wind and, consequently, that the effective sail area will be adjusted automatically by the weight A to the pressure of the wind,
.even when said wind is very unsteady or gusty.
The dash-pot M forms a cushioned stop, against which the weight A holds the mill while at work and obviates the jar that would otherwise be destructive when the windmill rights up after a heavy gust of wind has passed by. In case ofa storm or extra heavy wind, the vane-frame is swung down by the wind against the stop m on the mast l3, opposite to the dash-pot M, in which position the sails D present only their bottom edges to the wind, thus reducing the resistance to the wind to a minimum. When it is not desired to run the windmill it may be drawn down to this position from the ground by the rod L which is then secured to a stop (not shown) on one of the posts of the tower.
It is evident that this windmill will not stop work until the force of the wind becomes destructive, as the universal coupling H11 1-1 will transmit the power from the wind-wheel shaft to the tower-shaft at any inclination of the main shaft E until the sails take the po sition shown by the dotted lines in Fig. 1, when they present only their lower edges to the wind, and consequently produce no power.
By placing the jack-shaft as near the top of the tower as practicable the length of the tower-shaft G, as well as its weight, and consequently the friction upon its bearings, is reduced to a minimum. This also raises the grooved drive-pulley K far enough above the ground to give considerable range of motion to the weighted tightener-pulley K which in turn allows the power to be transmitted to the pulley K, located on various machines, which may be directly under the windmill, or at a considerable distance therefrom, as shown in Fig. 6, in which, when the rope is is connected to a machine P, located close to the tower, the position of the tightener-sheave K is shown by the full lines to be near the ground at K while when the rope is connected to drive the machine 1), located at the greatest distance possible from the tower, its position is shown by the dotted lines k to be close to the grooved driving-pulley K, near the top of the tower. It is obvious that this arrangement would permit the application of power to machines placed at points between those shown in Fig. 6, as well as to the machines placed on the opposite side of the tower or at different elevations.
The bevel gear J is provided with a crank pin 7' to which the pump-rod 3' may be connected when the pumpis located beneath the windmill. However, it is not necessary to locate the mill over the well and pump, as is usual, as power may be transmitted to a pump located at a considerable distance from the windmill by means of the endless rope is. This arrangement is particularly advantageous where it is desired to pump water from a lake or stream, in which case the windmill may be located high up on the bluff or embankment, where a steady wind-pressure is available, and the pump may be placed at the waters edge. By this arrangement the windmill is of incalculable value for irrigation purposes, for many of our Western rivers, located in sections where irrigation is necessary, are apparently dry when water is most needed,
' though quite a quantity of water may be flowing through the coarse gravel in the bed of the stream out of sight, and by placing a pump over said running water and in the bed of the stream sufficient water may be raised to make much now worthless land productive. However, it would not be practicable to place a windmill in the bed of the stream, for the reason that great damage would be done to it during high water, and also on account of the expense necessary to raise it high enough to secure an effective wind-pressure; but by placing the windmill and tower upon the bank exposed to the wind and above high water and transmitting motion therefrom to apump in the bed of the stream by means of the rope k and grooved pulleys a constant supply of Water may be had when most needed, for the position of. the pump in the stream may be changed as necessary to accommodate it to the stage of the water.
What I claim as new is- 1. In a wind motor the combination of a vane connected by horizontal pivots to a hollow vertical mast adapted to turn with the vane, and a wind-wheel rotating a vertical shaft journaled upon the vane, substantially as described. 1
2. In a wind motor the combination of a vane connected by'horizontal pivots to a hol-- ling connecting the wind-wheel shaft with the power shaft, substantially as described.
3. In a wind motor the combination of a vane connected by horizontal pivots to a hollow vertical mast adapted to turn with the vane, a wind-wheel rotating a shaft j ournaled upon said vane, a counter balance weight adapted to hold the wind-wheel shaft vertical in ordinary winds, and a universal coupling communicating motion to a vertical power shaft rotating within the hollow mast, substantially as described.
4:. In a wind motor the combination of a vane pivotally connected with a hollow vertical mast adapted to be turned thereby, a windwheel rotating a shaft journaled upon said vane, a weight suspended from the windward end of the vane, a chain or cable attached to the leeward end of the vane and extending through the hollow mast, and a slot in the lower portion thereof to a sliding collar, a shifter fork engaging a groove in the sliding collar, and means for drawing it and the sliding collar downward to incline the wind-wheel and shaft from the vertical, substantially as and for the purpose described.
5. In a wind motor the combination of a vane pivotally connected to a hollow vertical mast adapted to be turned thereby, a windwheel rotating a shaft'journaled upon the vane, a ring or link rigidly attached to one end thereof, a vertical power shaft rotating within the hollow mast, a ring or link rigidly attached to the upper end thereof, and a loose ring engaging the-rigid rings upon the said. shafts, substantially as and for the purpose described.
6. In a wind motor the combination of a vane connected by horizontal pivots to a vertical mast adapted to be turned thereby, a wind-wheel rotating a vertical shaft journaled upon the vane, a weight attached to a bracket suspended from the windward end of the vane, a dash-pot attached to said bracket, and a plunger attached to the vertical mast adapted to fit into the dash-pot and form a cushioned stop against which the vane is held in ordinary winds, substantially as described.
7. In a wind motor the combination of a vane connected by horizontal pivots to a ver-' tical mast adapted to be turned thereby, a
counter-balance weight attached to the wind ward end of the vane, ashaft journaledupon said vane, having wheels attached thereto, and sails located between said wheels and pivotally attached to the periphery thereof,
substantially as described.
In testimony whereof I have hereunto set my hand and affixed my seal in presence of two subscribing witnesses.
HENRY s. HOPPER. a s.]
Witnesses:
JOHN H. POWELL, CHARLES M. JOHNSON.
US544228D Windmill Expired - Lifetime US544228A (en)

Publications (1)

Publication Number Publication Date
US544228A true US544228A (en) 1895-08-06

Family

ID=2612975

Family Applications (1)

Application Number Title Priority Date Filing Date
US544228D Expired - Lifetime US544228A (en) Windmill

Country Status (1)

Country Link
US (1) US544228A (en)

Similar Documents

Publication Publication Date Title
US5823749A (en) Vertical-axis wind turbine with two-phase sails
JPS58500531A (en) Comprehensive wind and wave utilization equipment
US756616A (en) Windmill.
US705922A (en) Wind-motor.
US243169A (en) Windmill
US544228A (en) Windmill
CA2666048A1 (en) Buktukov-3 wind power plant
US177597A (en) Improvement in windmills
NO325833B1 (en) Darrieus turbine
US609378A (en) Horizontal windmill
US512352A (en) Windmill
US504301A (en) Territory
US988098A (en) Windmill.
US1740595A (en) Stream motor
WO2019073189A1 (en) Vertical axis wind turbine
US399645A (en) Windmill
US298570A (en) James b
US684054A (en) Wind and water power pump.
US375462A (en) Automatic regulator for wind-wheels
US1171584A (en) Windmill or motor.
US159207A (en) Improvement in windmills
US207701A (en) Improvement in wind-engines
US177805A (en) Improvement in windmills
US1644912A (en) Windmill
US177057A (en) Improvement in wind-wheels