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 M4, M5, loosely mounted upon short supporting shafts M6, M7, journaled in uprights M8, M8 secured to the casing M. To each of the spur wheels M4, M5 is secured the outer end of a coil spring M9, M10, respectively, the inner ends of said springs being secured to the respective shafts M6, M7, the arrangement being such that when the springs are placed under tension by the rotation of the shafts M6, M7, the force of the springs rotates the spur wheels M4, M5, thereby rotating the spur wheel M³, shaft M¹ and the spur wheel M².
Also mounted upon each of the respective short shafts M6, M7, and keyed thereto, is a ratchet wheel M11, M12, and adjacent thereto and loosely mounted upon each of said shafts M6, M7 is a pawl carrier plate M13, M14, each carrying a pawl indicated at M15, M16, which is adapted to engage the teeth of the ratchet wheels M11, M12, being held in engagement therewith by springs, one of which is shown at M17, secured to said pawl carrier M13. Suitably mounted upon the casing M, and adapted to engage the teeth of the ratchet wheels M11, M12, is a detent M19, to prevent reverse movement of said ratchet wheels.
The pawl carrier plate M13 is provided with a pin M21, and secured thereby loosely to said carrier is one end of a connecting rod M21ª, the other end of said connecting rod being connected to one end of a longitudinally flexible coupling M22, the other end of said coupling being secured by means of the connecting rod M23 to the power transmission lever L. The function of the flexible coupling M22 will be hereinafter referred to.
The pawl carrier M13 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 M14, whereby, when motion is imparted to pawl carrier M13 and, through the pawl M15 to the ratchet wheel M11, motion is imparted to the pawl carrier M14, and through its pawl M16 to the ratchet wheel M12. 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 M22 comprises a tubular casing N4, which is provided at one end with an opening N5, through which projects a rod N6 having a head N7, which is adapted to bear against a spiral spring N8 mounted within said casing, the other end of said rod N6 being connected to the rod M23.
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 M11, M12, and winding up the springs M9, M10, 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 M22 will now be quite clear. It will be seen that the coil spring N8 will be sufficiently strong not to give under the pull of the lever L except when the springs M9, M10 are wound full. When that condition exists, the coil spring N8 will give, under the force of the lever L, and