Patent GB-191514111-A (GB)
Title: Improvements in or connected with Electromagnetic Power Transmission Gearing.
Inventor: ZOELLY HEINRICH
IPC: F16H49/00
Filed: 1915-10-05
Abstract: 14,111. Zoelly, H. Oct. 6, 1914, [Convention date]. Rack railways.-Power is transmitted by magnetic attraction or pull between the flanks of meshing teeth. The invention is stated to be applicable to cog-wheel railways. As shown in Figs. 2 and 8 applied to spur gearing, the driving-wheel I and driven wheel II form part of the magnetic circuit of an electro-magnet 47, the wheel I producing clockwise rotation of the wheel II owing to the magnetic pull exerted by the left-hand flanks of teeth 13, 15, 17 upon the right-hand flanks of teeth 14, 16, 18. The flanks of teeth which exert no useful magnetic pull one upon another may be cut away as shown in Fig. 4. To secure the requisite airgaps between the flanks of the two sets of spur teeth, an auxiliary pair of spur-wheels 56, 55, the teeth of which mesh without any play, may be fixed on the two shafts 41, 42, somewhat as shown in Fig. 8. The magnetic flux produced by the electro-magnet 47 and consequently the magnetic pull between the teeth may be regulated automatically in such a manner that the meshing teeth keep the required positions when the torque is varied; for example, the flanks may be in contact or may be apart a fixed distance during running, or a small amount of play may be arranged for. In one regulating arrangement, Fig. 8, the arm 69 of a variable resistance 71 in circuit with the battery 45 exciting the electro-magnet 47 is connected to differential plungers 62, 63 of an hydraulic regulator. Oil is drawn by a pump 58 from a receptacle 59 into an annular chamber 61 and flows back through a passage 64 in the plunger 62 into a space 65 on the other side of the plunger and thence through the hollow plunger rod 66 into the receptacle 59. The spur-wheel 56 is mounted by means of a helical groove and web upon the driving-shaft 41 so as to move axially thereon when variations of torque occur and constrict to a greater or lesser extent the outlet in the rod 66; the plungers 62, 63 are thereupon moved in one or the other direction, causing variation of the resistance 71. In a modification, the axial movement of the wheel 56 is used to move the arm 69 directly, the hydraulic apparatus being omitted. in another arrangement, Fig. 10, the main gearing comprises two pairs of spur-wheels 75, 76 and 77, 78 magnetized by a stationary coil 82 surrounding the shaft 79, the gearing system being driven from the shaft 86 through an elastic coupling which controls the supply of oil to the differential plungers 98, 99 connected to the rheostat arm 85. The plunger 99 is acted upon by a spring 106. Oil is drawn from a receptacle 96 by a pump 95 into the annular plunger chamber 97, and thenco flows through a pipe 100 and the hollow shaft 93 into a chamber 102, formed by two rings, one fitting inside the other, with overlapping slots which act as a throttle for the oil. One member of the coupling has two pins 88, 89 mounted between plate springs 90, 91 on the other member. In a further form of regulator, Figs. 14 and 15, the torsion of a rod 117 coupled by means of square end portions both to the driving-shaft 111 and the axle 116 of the spur-wheels 112, 113 is utilized to control resistance coils 119 mounted in a cylinder 118 rigidly coupled to a shaft 111. The ends of these coils form contact pieces 121 .. 125 which coa.ct with a contact segment 127 fixed to the axle 116. Instead of altering the current in the circuit of the electro-magnet, the number of its turns of windings may be varied.