Part 2

“Mention has been made in a preceding article of the effect of unequal expansion upon two different metals that have been bolted together. It is by this principle that the action of the ordinary thermostat, so familiar now as a controller and regulator of the temperature of high buildings, is explained--a rod made up of two different metals whose rates of expansion are different. When the temperature of the room in which the thermostat is placed becomes too high the rod curls toward the metal point S and touches it, completing an electrical contact which causes a motor to shut off the draft. When the temperature of the room falls below a certain point the rod curls in the opposite direction toward the metal point T. This causes a motor to open the draft and thus furnish a more abundant supply of hot air.

“Everybody in these days of cheap and reliable timepieces carries a watch. And yet there are very few who appreciate the methods and devices by means of which the troublesome expansion and contraction of metals are corrected, in order that a watch may keep correct time. The balance wheel of a watch corresponds to the pendulum of a clock, and any variation in its dimensions will cause it to move faster or slower, as the case may be. The hairspring is really a long strip of metal which becomes weakened in its effect when expanded by an increase in temperature and has its power augmented when contraction takes place.

“To correct both of these conditions the rim of the balance wheel is made up of two different metals, the outer part brass, the inner part iron. When the hairspring becomes weaker by expansion the brass of the balance wheel also expands; but as it expands more than the iron to which it is bonded, it curls in toward the center of the wheel, making practically a wheel of smaller diameter, and causing the same effect as is produced when a clock pendulum is shortened. Exactly the opposite conditions obtain when the timepiece is exposed to extreme cold and the balance wheel has its diameter increased, thus causing a slowing up to counteract the increased strain produced by the contraction of the hairspring. The same principle is applied in the construction of first-class clocks. Any uncorrected variation in the length of a pendulum is fatal to the timekeeping quality of a clock. A gridiron pendulum made up of alternate rods of steel and brass serves to correct the result of the expansive force.

“The central steel rod passes through holes in the lower horizontal framework and supports the bob at the lower end. The steel rods are so arranged that they will expand downward, while the brass rods expand upward and the total length of each metal used is exactly sufficient to counteract each other’s expansion, and the centre of the bob will remain at a constant distance from the point of suspension.”

Scientific men and engineers are more or less familiar with the phenomena of expansion. But no inventor produced a system capable of utilizing this force to run a clock until Bangerter succeeded in mastering the problem.

Bangerter’s clock is unquestionably a triumph of human ingenuity. It is a mechanical masterpiece. Herewith follows the complete specification:

SPECIFICATION

TO ALL WHOM IT MAY CONCERN:

Be it known that I, FRIEDRICH BANGERTER, of the City of New York (Borough of Richmond), County of Richmond and State of New York, have invented certain new and useful improvements in

APPARATUS FOR THE EDUCTION, STORAGE AND APPLICATION OF ENERGY FROM EXPANSIBLE MATERIALS,

of which the following is a full, clear and exact specification, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to apparatus whereby energy may be educed from expansible materials, due to the expansion and contraction thereof on changes of temperature, and the said energy either applied direct or stored and applied for the purpose of operating machines and devices of various kinds.

I show and describe herein two forms of apparatus for obtaining such expansion and contraction and the required energy therefrom, and I also show two forms in which the energy so obtained is accumulated and stored. In connection therewith, I show the application of my invention to the running of clocks, but it will be understood that the invention is not limited in its application to that particular class of machine, and that it may be applied to any use of which it is susceptible.

It is well known that all metals are capable of some degree of expansion and contraction, and some metals have this property in greater degree than others. The amount of expansion for each degree rise in temperature is quite regular, and is called the co-efficient of expansion. It is also well known that zinc has this property in greater degree than any other of the solid metals, its co-efficient of linear expansion being appreciably higher. For this reason, as well as because of its relatively low cost, I preferably make use of zinc in the construction of the expansible parts of my apparatus.

One of the objects of my invention, therefore, is to provide an expansion device of novel construction and arrangement, which will generate energy and maintain motion during changes in temperature, to such an appreciable and useful amount, as to constitute it in fact a temperature motor.

A further object of my invention is to provide means for accumulating or storing the energy thus generated.

A further object is to provide means for applying the energy thus generated and stored.

Other objects, such as compactness, durability and comparatively low cost of the apparatus, will appear in the following description, in which reference is had to the accompanying drawings.

In the drawings:--

Fig. 1 is a front elevation, showing the application of my invention to a clock provided, in this case, with a mainspring as usual;

Fig. 2 is a rear elevation of the same with a part removed;

Fig. 3 is an enlarged perspective detail showing how the strips forming part of the expansion member or coil are connected up;

Fig. 4 is a sectional view, on lines 5--5 of Fig. 1;

Fig. 5 is an enlarged detail elevation, with parts removed;

Fig. 6 is an enlarged detail cross section of the central portion of the apparatus, with part broken away;

Fig. 7 is a rear elevation of the same with parts broken away;

Fig. 8 is an enlarged detail of the upper portion of the apparatus shown in Fig. 4, with parts removed;

Fig. 9 is a perspective detail, partly broken away;

Fig. 10 is an enlarged detail of a portion of the ratchet mechanism shown in the lower portion of Figs. 6 and 7;

Fig. 11 is an enlarged section of a flexible coupling shown in Fig. 7;

Fig. 12 is an elevation of a modification of the expansion coil;

Fig. 12ª is a perspective view showing how two of such modified expansion coils may be connected;

Fig. 13 is a front elevation showing my invention applied to another form of force storage mechanism;

Fig. 14 is a plan view of same, on lines 14--14 of Fig. 13;

Fig. 15 is a rear elevation on lines 15--15 of Fig. 14;

Fig. 16 is a vertical section on lines 16--16 of Fig. 14;

Fig. 17 is an enlarged detail of part of the apparatus shown in the upper portion of Fig. 16;

Fig. 18 is an enlarged detail of the ball-discharging means shown in the lower portion of Fig. 16;

Fig. 19 is an enlarged detail of the loading device shown in the opposite part of the lower portion of Fig. 16; and

Fig. 20 is a plan view on lines 20--20 of Fig. 13.

Referring to the construction illustrated in Fig. 1 to 11, inclusive, B represents the outer frame of the apparatus.

Mounted within the outer frame B is an inner frame comprising the uprights C, C¹, which are rigidly secured by cross-bars D¹, D².

The outer frame B, as well as the inner frame uprights C, C¹ are preferably formed of wood or other material capable of a low degree of expansion.

Within the upper and lower ends of the inner frame are anti-friction knife-bars E, E^¹{1}, the upper one of which, E, has each end within a vertically disposed slot E² in the uprights C, C¹, within which said knife-bar may be moved vertically, as hereinafter described.

Each end of the lower knife-bar E¹ lies immovable within a recess in a plate E³ mounted on each of the uprights C, C¹.

These knife-bars, which are preferably formed of hardened steel, have oppositely disposed relatively sharp edges E^{5}, which act as bearings for a series of horizontally disposed anti-friction levers, F, F¹, which I will term balance-levers, since they are intended to balance evenly and freely on the thin edges of the knife-bars with little friction somewhat in the nature of a scale-balance. These levers are pivotally connected to a series of metallic expansion strips G, G¹, G², G³, etc., the construction and arrangement and manner of connecting up the same being more clearly shown in Fig. 3.

It will be observed that the arrangement of the levers F and expansion strips G, G¹, etc., is such as to form, in effect, a spiral, the short strip G being connected to one end of one of the balance-levers F, and the strip G being connected at its lower end to the opposite end of said lever, the upper end of said strip G¹ being connected to one end of the first one of the levers F¹. To the opposite end of said lever F¹ the upper end of strip G² is connected, the lower end of said strip being connected to the left-hand end of the second one of the levers F, and so on to the final short strip G^{x}. The levers F, F¹ must be formed of a metal capable of withstanding great strain without bending, and for this purpose I prefer to use the metal known as macadamite.

For convenience of designation, I will refer to each of these groups of balance-levers F, F¹, and expansion strips G, G¹, etc., as expansion coils, and while I have herein shown but two sets of such expansion coils, it is to be understood that there may be any number of such sets desired, and any desired number of strips and levers composing such coils, depending upon the character of the work to be performed.

Furthermore, I desire it to be understood that when I use the terms “strips"--as characterizing the members connecting the balance-levers--either in the specification or claims, I do not limit myself to the form of connecting member or “strips” shown, but mean to include in the use of the term “strips” any other form such as wires, rods or bars of either square, round, hexagonal or other cross sectional shape.

The ends of the short strips G, G^{x} are connected by wires H, H¹ with the opposite ends of what I will term a coil lever I, which, as more clearly shown in Fig. 5, is keyed to a shaft J, which latter has its end journaled upon the cross-bars J¹, J² secured to the uprights C, C¹ of the inner frame of the apparatus, and this shaft I will name a coil shaft.

Keyed to the coil shaft J is a lever K, which it may be proper to designate as a stress lever, since from it is suspended a weight K¹, the function of which is to place a certain amount of stress upon the series of expansion strips and balance-levers composing the expansion coil, keeping the metal of the strips slightly stretched and preventing any loss of motion at the different points of connection, and thereby furthering a very important object, which is to make of each series of expansion strips

and balance-levers a single spiral unit, throughout which the expansion and contraction of the strips are transmitted.

Also keyed to the shaft J is a power transmisson lever L, and any rotary motion imparted to said shaft is necessarily imparted to the lever L in the form of reciprocating motion.

Referring now to the power storage device, one or a number of which may be used in connection with my expansion coils.

Disposed approximately midway of the uprights C, C¹ and within casing M, secured at its ends to said uprights, is rotatably mounted a power transmission shaft M¹, keyed to which is a spur wheel M². Also mounted on the shaft M¹ is a spur wheel M³, meshing with which at its upper and lower sides are two spur wheels M^{4}, M^{5}, loosely mounted upon short supporting shafts M^{6}, M^{7}, journaled in uprights M^{8}, M^{8} secured to the casing M. To each of the spur wheels M^{4}, M^{5} is secured the outer end of a coil spring M^{9}, M^{10}, respectively, the inner ends of said springs being secured to the respective shafts M^{6}, M^{7}, the arrangement being such that when the springs are placed under tension by the rotation of the shafts M^{6}, M^{7}, the force of the springs rotates the spur wheels M^{4}, M^{5}, thereby rotating the spur wheel M³, shaft M¹ and the spur wheel M².

Also mounted upon each of the respective short shafts M^{6}, M^{7}, and keyed thereto, is a ratchet wheel M^{11}, M^{12}, and adjacent thereto and loosely mounted upon each of said shafts M^{6}, M^{7} is a pawl carrier plate M^{13}, M^{14}, each carrying a pawl indicated at M^{15}, M^{16}, which is adapted to engage the teeth of the ratchet wheels M^{11}, M^{12}, being held in engagement therewith by springs, one of which is shown at M^{17}, secured to said pawl carrier M^{13}. Suitably mounted upon the casing M, and adapted to engage the teeth of the ratchet wheels M^{11}, M^{12}, is a detent M^{19}, to prevent reverse movement of said ratchet wheels.

The pawl carrier plate M^{13} is provided with a pin M^{21}, and secured thereby loosely to said carrier is one end of a connecting rod M^{21ª}, the other end of said connecting rod being connected to one end of a longitudinally flexible coupling M^{22}, the other end of said coupling being secured by means of the connecting rod M^{23} to the power transmission lever L. The function of the flexible coupling M^{22} will be hereinafter referred to.

The pawl carrier M^{13} also carries, at its lower end, a pin N, and loosely mounted thereon is one end of a connecting rod N¹, the other end of said rod being connected to a pin N² secured to the pawl carrier M^{14}, whereby, when motion is imparted to pawl carrier M^{13} and, through the pawl M^{15} to the ratchet wheel M^{11}, motion is imparted to the pawl carrier M^{14}, and through its pawl M^{16} to the ratchet wheel M^{12}. From the pin N² is suspended a weight N³ to return the pawl carriers to their lowermost positions when they complete their upward travel.

The flexible coupling M^{22} comprises a tubular casing N^{4}, which is provided at one end with an opening N^{5}, through which projects a rod N^{6} having a head N^{7}, which is adapted to bear against a spiral spring N^{8} mounted within said casing, the other end of said rod N^{6} being connected to the rod M^{23}.

The operation of the apparatus, as thus far described, will be more readily apparent from an inspection of Fig. 5.

Assuming that the expansion coil there shown has been subject to a normal temperature of say 75 degrees Fahrenheit, and at that temperature the lever L is in the position shown in full lines on a decrease in temperature of say 10 degrees, the contraction of the coil, which will operate upon its entire length, will exert a pressure at the ends thereof in the direction of the arrows, the result of which will be to rotate the shaft J and raise the lever L against the force of the weighted lever K (carrying the latter therewith) to the position shown in dotted lines, thereby actuating the ratchet wheels M^{11}, M^{12}, and winding up the springs M^{9}, M^{10}, of the power-storage device, the force there stored being afterwards taken off, as required, through the medium of the power transmission shaft M¹ and spur wheel M² and any suitable gearing or power transmission means.

The function of the flexible coupling indicated at M^{22} will now be quite clear. It will be seen that the coil spring N^{8} will be sufficiently strong not to give under the pull of the lever L except when the springs M^{9}, M^{10} are wound full. When that condition exists, the coil spring N^{8} will give, under the force of the lever L, and

no further power will be applied to the springs M^{9}, M^{10}. When, however, those springs have become unwound to a sufficient extent the spring N^{8} of the coupling M^{22} will be stronger than the springs of the power-storage device and will transmit, from the expansion coil, the force necessary to wind said springs as often as they become unwound; in other cases the force will be expended in simply compressing the coil spring N^{8} without effect upon the springs of the power-storage device.

Referring now to what I will term the force-increasing devices, which are more clearly shown in Figs. 1, 2, 4, 8 and 9.

Near each end of the upper knife-bar E, and contacting therewith at its under surface, is a support O, in the form of a flat-headed bolt (Fig. 8), the shank of said bolt passing through one end of lever O¹, which is fulcrumed at O² upon the upper surface of a cross-bar O³ securely fastened to the rear portion of the uprights C, C¹. To the front of said uprights is rigidly secured a second cross-bar O^{4}, and at the lower portion of said uprights and rigidly secured thereto is a third cross-bar O^{5}, against the under surface of which rests a lever O^{6} (Fig. 9) having its fulcrum point at O^{7}.

As shown in Fig. 2, there are three sets of the levers O¹, at the upper end of the expansion coils at the rear side thereof below the knife-bars E, one lever at each end of said bar and one in the middle thereof. As these levers act directly upon the under surface of the knife-bars E to raise the same I will call them knife-bar lifting-levers. There are also the same number of levers O^{6} at the lower end of the expansion coils below the cross-bar O^{5} projecting through to the forward side of the apparatus, as shown in Fig. 1.

Rigidly secured to the cross-bar O^{4} is one end of a relatively heavy metallic expansion strip O^{8},--preferably formed of zinc--the lower end being secured to one end of the lever O^{6}; to the opposite end of the lever O^{6} is secured the lower end of a similar but longer zinc strip O^{9}, the upper end of the strip O^{9} being secured to the rear end of the lever O¹. As shown in Figs. 1 and 2, there are two of these strips O^{8} at the front and two of the strips O^{9} at the rear of the apparatus.

In addition to the heavy strips O^{8}, O^{9}, there is provided at the front of the apparatus a heavy wide expansion sheet or strip O^{10}, which, at its upper end, is rigidly secured to the cross-bar O^{4}, and at its lower end to the front end of the middle one of the levers O^{6}. A similar heavy wide expansion sheet or strip O^{11} is secured, at its lower end, to the rear end of the middle lever O^{6}, and, at its upper end, to the middle one of the levers O¹.

These heavy strips O^{8}, O^{9} and sheets O^{10}, O^{11} are preferably formed of zinc, and are not only capable of great expansion and contraction, but will be capable by their contraction of lifting the entire weight of the knife-bars E, with the carried balance-levers and expansion strips of expansion coils, the operation thereof being as follows:

The front strips O^{8} and rear strips O^{9} and the front sheets O^{10} and the rear sheets O^{11} are connected to the levers O^{6}, so as to form, in effect, single expansion strips and sheets of relatively great length. They are fastened, however, at their front upper ends to the cross-bars O^{4}, so that the expansion cannot extend beyond that point and takes place in a direction towards the opposite end, and, of course, the contraction takes place in the opposite direction. Assuming now that at a temperature of say 75 degrees Fahr. these heavy strips and sheets lie in the position shown in Figs. 4 and 9 (the heavy strips O^{8}, O^{9} being shown in Fig. 9, and the heavy wide sheets O^{10}, O^{11} in Fig. 4), on a decrease in temperature of say five degrees Fahr., the heavy strips O^{8}, O^{9} and sheets O^{11}, O^{12} will contract in the direction of the arrows, depressing the rear ends of the levers O¹, O^{6}, and thereby through the levers O¹ lifting the knife-bars E, and the balance-levers suspended thereon, with the result that the force normally exerted at the ends of each expansion coil is increased to the extent of the lifting power of the contraction of the metal strips and sheets.

I have found by experiment as well as observation that the average daily change of temperature in residence and office buildings is about five degrees. Sometimes the changes will be much greater, and sometimes less. On even a low average of temperature change, my apparatus will be able to generate force in larger amounts than required, and the surplus will be stored in a power-storage device such as above described, or by means hereinafter referred to, which surplus will

be drawn upon when it should happen that the average temperature is approximately uniform.

For clearness of illustration, I have shown, as above stated, but two sets of expansion coils, but there is no limit to the number that may be used. Assuming that we have an apparatus with four expansion coils, each knife-bar holding 50 balance levers, giving a total of 200 levers, with expansion strips of the same number, in 5-foot lengths, we would have a total of 1,000 linear feet of zinc strips, which entire length of strips will, on the slightest change of temperature, get longer or shorter. The expansion and contracting of this 1,000 feet of zinc strips for every temperature change of 5 degrees Fahr. will be 1 inch. Now, assuming that the knife-bars are pulled upward by heavy strips O^{8}, O^{9}, and sheets O^{10}, O^{11} of five feet length (making ten feet for the front and rear strips and sheets), on a decrease in temperature of 5 degrees Fahr. the upward movement of those bars will be 10-1000 of one inch; this contraction (10-1000) will now be multiplied as many times as there are levers and strips in the expansion coils, viz., 200 times, which would be 2 inches, and this, together with 1 inch from the contraction of the expansion coils alone, will give a total movement of 3 inches. If the strips are of a capacity to pull or lift 100 pounds, we obtain a lift of 100 pounds 3 inches. As thirty-three per cent approximately must be deducted for loss by stress (it being necessary to place the coils under strain, as shown in the drawings and described above), the final result will be a power to lift 100 pounds 2 inches, or 10 pounds 20 inches, and this force will be sufficient to run a large sized time clock with powerful striking force.