Patent GB-288292-A (GB)
Title: Method of and means for equalising forces and inertia effects in oscillating systems
IPC: B06B3/00
Filed: 1928-03-31
Abstract: 288,292. Schieferstein, G. H. April 8, 1927, [Convention date]. Addition to 248,794. Machine'ry, utilizing inertia to obtain movements in; balancing reciprocating parts of machinery.-Balanced oscillatory or like systems working in opposition or phase displacement of 180‹ and having the characteristics of the parent invention, are driven through " loose coupling " means comprising rotary unbalanced masses coupled together by members "which whilst acting rigidly or approximately so in the transmission of torque are flexible, radially or in the direction of stroke of the oscillatory members and also axially. The invention is shown applied to the operation of a unidirectional driving device and to the actuation of screens in circular, elliptical &c. paths, various means for elastically supporting the screens and various forms of rotary coupling members being described. As applied to a system in which two reciprocatory masses a', a<2>, Fig. 1, arranged between springs b<1>, b<2>, are to be set in oscillation in opposite phase so as to avoid the transmission of vibrations to the foundation or support, a driving shaft 1 terminating in a disc 2 is coupled to a series of discs, carrying eccentrically disposed weights 3, 4, 7, 8, by #-shaped leathers or steel springs 5 which transmit rotation but allow lateral displacement of the discs under the action of centrifugal force, the discs however being otherwise constrained, as by levers &c., so that they can only fly outwards in the plane corresponding to the direction of stroke. The discs are coupled in series, the outer discs 3, 4 being mounted on spindles 6, 10 revolving in the arms 12, 13 of a frame connected to the mass a<2>, whilst the inner pair of discs 7, 8 is carried by a spindle 9 revolving in a mounting on a rod 14 connected to the mass a<1>, the weights being arranged at 180‹ as shown so that the masses a<1>, a<2> are yieldingly driven simultaneously in opposite directions. In modifications, a single weighted disc is connected to each oscillatory member, and the oscillatory members may both be on the same side of the rotary member with the constraining springs arranged therebetween. The #-shaped coupling members 5 may comprise a plurality of separated layers. Alternative coupling means comprise pairs of hinged links, and Hooke's joints, flexible discs, or other universal connections in combination with telescopic shafting, Fig. 20. In the form shown in Figs. 4 and 6, the oscillatory systems comprise frames a<1>, a<2>, connected to unbalanced rotary masses mounted at the upper ends of levers 8, and serving to operate a pair of coaxial unidirectional driving members F. The elastic constraint is provided by rubber balls b<1>, b<2> arranged between transverse plates or partitions a<11>, a<22> carried by the longitudinal frame members. The frames thus reciprocate in opposite directions, each frame being connected to the top of one unidirectional member F and through diagonal connections a<3>, a', to the bottom of the other. Driving means for imparting circular, elliptical, &c. motion in phase displacement of 180‹ to a pair of screens a', a<2> is shown in Fig. 9. A sbaft 9, mounted transversely in the upper screen a', carries discs with eccentric weights 7, 8 and is coupled by torque transmitting but laterally yielding members 5 to discs with diametrically opposite weights 3, 4 on spindles mounted in a frame 11, 14 secured to the lower screen. The drive is transmitted from a shaft 1 through a third coupling 5. The screens are supported at their ends, Fig. 7, by radial springs attached to fixed shafts x, allowing freedom for the motion required. Alternative mountings comprise soft rubber blocks, flat springs, or -pneumatic tyred wheels or rollers which may be located in frames closely fitting the tyres or of greater internal diameter, or forming an elliptical track as shown in Fig. 14. Reference has been directed by the Comptroller to Specifications 9953/92 and 20148/93.