Patent GB-943541-A (GB)
Title: High-speed synchronizing clutch
IPC: F16D25/10
Filed: 1960-08-30
Abstract: 943,541. Positive clutches; clutch control. DYNETICS Inc. Aug. 30, 1960 [Sept. 16, 1959], No. 29829/60. Headings F2C and F2L. In an hydraulically actuated, frictionally synchronized, positive clutch for ship propulsion, wherein an internally toothed sleeve 14 engaging an externally toothed driving (or driven) member 12 is axially moved to engage an externally toothed driven (or driving) member 13, a piston 24, acting through a plate 34, initially engages a synchronizing friction disc clutch 17, firstly through the sleeve 14, spring-loaded balls 37 and a presser plate 21, and secondly, on yielding of the balls 37, through pre-synchronous drag-torque balking engagement of cam surfaces in holes 43 in the plate 34 and on shoulders 42 of balk pins 40 secured to the presser plate 21, and finally, on synchronism, cams the pins into passing through the holes 43, thereby releasing the friction clutch for slow, clutch-aligning, relative rotation of the members 12, 13, and simultaneously pushes the sleeve 14 into positive clutch engagement. The disc clutch 17 comprises discs alternately splined to the presser plate 21 and the member 13, and engaging rings 23, 22 which latter ring is axially screwadjusted by a lockable ring 42<1> to adjust to a minimum the axial travel, after friction clutch release, of the teeth on the sleeve 14 with respect to those on the member 13, which teeth are bevelled to facilitate engagement. Clutch reaction is taken, and external axial forces may be transmitted, by a link 38 rigidly secured at one end to the member 13 and connected at the other end to the member 12 through a thrust bearing 39. The plate 34 is externally splined to the sleeve 14. Reduced extremities 41 of the balk pins 40 limit pre-synchronous relative rotation between the member 12 and the presser plate 21. The pins may be cantilevered on the presser plate or, as shown, supported by their extremities 41 in a bending moment distributing ring 44 rotatably mounted in the member 12. Different clutch engaging characteristics may be obtained by varying the angles of the cam surfaces. Spring-loaded balls 36 locate the sleeve 14 with respect to the member 12. For engagement, oil is fed to the left of the piston 24 through a passage 32, and for disengagement to a chamber 27 through a passage 33. During disengagement the balls 37 re-engage the sleeve 14 to withdraw the presser plate 21, the discs being spaced apart by continuously supplied cooling oil. In Fig. 9 (not shown), the piston comprises two parts such that, during engagement, initially full piston area is effective and finally, when the friction clutch is released, a reduced piston area, sufficient after synchronism, is utilized. Control.-In Figs. 4, 5, pressure oil is supplied, to the passages 32, 33 by a motor-driven pump 46, a standby handpump 47 or an emergency accumulator 48, through an electromagnetic four-way valve 44 manually controlled through " engage " and " disengage " solenoids 62, 58. A main switch (not shown) controls " engage " and " disengage " contacts 61, 69. A flange 49 on the sleeve 14 has an axial lost-motion connection with a control slide 50 located by a spring-loaded ball 51. In the disengaged position shown, the slide 50 has actuated a switch 53 to switch on a " disengaged " indicator light 55a, prepare a holding circuit to the " disengage " solenoid 58, and prepare a circuit to the " engage " solenoid 62. For engagement, closure of the contacts 61 completes the circuit to the " engage " solenoid 62 to actuate the piston 24 and move the sleeve 14 to the right. When the clutch is finally engaged the slide 50 is tripped to open the switch 53 with its related contacts and close a switch 63 to switch on an " engaged " indicator light 66 and prepare a circuit to the " disengage " solenoid 58. If the clutch does not engage in a given time a time delay relay 70 opens contacts K-1 to the " engage " solenoid 62, closes contacts K-3 to complete the holding circuit to the " disengage " solenoid 58, and closes contacts K-2 to switch on a " Reject " indicator light 71. For disengagement, closure of the contacts 69 completes the circuit to the " disengage " solenoid 58. In Figs. 6, 7, 8 (not shown), a manual four-way valve replaces the electromagnetic valve 44. This arrangement includes electrical indicating means and electrically released, manually re-set means effecting disengagement should the clutch not be engaged within a given time determined by an hydraulic time delay device.