Patent GB-190613490-A (GB)
Title: Improvements in and relating to Frictional Change-speed Power Transmission Mechanism.
Inventor: LARSEN IVERT
Filed: 1906-06-12
Granted: 1907-02-07
Abstract: 13,490. Larsen, I., and Hardie, R. June 12. Variable-speed and reversing gearing.-Relates to a frictional variable-speed and reversing gearing embodying a direct drive and means for automatically disconnecting intermediate friction disks in applying the brake or in utilizing the direct drive. The device is described applied to a motorvehicle, a plan of which is shown in Fig. 1. Upon the motor shaft 23 is slidably mounted a driving- wheel 22 which is connected to the fly-wheel 33 by springs 36 and studs (not shown), one of which carries an adjustable nut to limit the rearward movement of the wheel under the expanding influence of the springs. The driving-wheel 22 drives intermediate friction disks 21, which in turn engage the driven transmission-wheel 24 slidably mounted upon the hollow shaft 26. The shaft 26 at one end is socketed to receive the rear reduced end 30 of the shaft 23, while at its other end it is reduced and is supported in a bearing 27, being connected by a universal joint 31 with the shaft 32 from which the back axle is driven. The friction disks 21 are mounted upon short horizontal shafts 40 slidably mounted in the bearing-brackets 43, 44, so that by operation of the foot-lever 82 the disks may be moved to engage the wheels 22, 24 with a variable friction grip. The fixed brackets 43, 44, Fig. 5, carry hardened rings 47, 53 in which are arranged ball bearings 46, 52 carried by hardened collars 45, 51 on the shaft 40. The outer ball bearing 46 is alined between a flange 48 upon the collar 45 and a second flange 49 upon a nut 50 screwed on to the shaft. At the inner end, the ball race is contained between a flange 40<a> on the shaft and a sleeve 56. Between the sleeves 55, 56 is carried a spring 54 placed under compression by means of bolts 57. To bring the disk 21 into engagement, the sleeve 55 is moved inwards by means of a cam device, shown more clearly in Fig. 7. This comprises a non-rotative member 60 held by the feather 61 in the bracket 43, and a corresponding member 62 supported by a sleeve 64 carried by the bracket 43. A thrust bearing 65 is arranged between this part and the sleeve 55. Upon partial rotation of the member 62, the axle 40 is moved inwards, carrying with it the disk 21, the initial pressure of the spring corresponding to a minimum load and being arranged to avoid slip. To effect a final pressure through solid connexions in cases of heavy loads &c., a cylindrical flange 72 upon the sleeve 55 is adapted to be brought up against an opposing shoulder 73 on the shaft. To operate the cam member 62, its rigid arm 86 is connected by a link 85, Fig. 3, to an arm 84 fixed upon the transverse shaft 80, which is carried in bearing-brackets 81 and may be rocked by the footlever 82. In a modified form, both the cam members may rock and have arms connected by links to oppositely-extending arms on the rockshaft 80. To lock the cam member in any desired position, the shaft 80 carries a ratchet sector 87 which is engaged by a pawl 88 pivoted by the pin 89 to the bracket 81 and normally pressed into action by a spring 91. To return the parts to their inoperative positions when the pawl is released, the arm 84 is drawn back by a dash-pot device comprising a spring 92 around the link 97, which terminates as a piston 96 and is arranged in a casing 93 pivoted to the bracket 41 and having a small air-hole. The pawl 88 may be automatically released by operation of the brake mechanism. The brakes are controlled by a foot-lever 100, Figs. 1 and 3, which forms the arm of a sleeve 101, mounted on the shaft 80. The hub 101 has also a downwardlyextending arm 102 connected by a link 103 to an arm 104 fixed on a transverse rock-shaft 105 carried in brackets 106. This rock-shaft carries, at the side of the machine, an arm 107 connected to the brake by the link 108. On the brake lever 100 is mounted a roller 110 adapted to engage a roller 111 carried by the pawl 88. The roller 110 effects disengagement of the pawl upon preliminary depression of the foot-lever, the brakes being brought into action by continued depression thereof. The transmission-wheel 24 is moved along the shaft 26 across the faces of the disks 21 by operation of the hand control lever 120, which is held in its desired position by any suitable locking-mechanism. The hand-lever is fixed to a short rock-shaft 121 carried by the bracket 106, and has an extension forming a rigid arm 122. This arm is connected by the link 123 to an arm 124 on a transverse rockshaft 125 mounted in standards 126 on the chassis of the car. Fixed on the shaft 125 are other arms 127 connected by links 128 to parallel rods 129 reciprocable in the supporting - hanger 27. This hanger, Fig. 11, comprises a cylindrical block 151 bolted to the cross-bar 17 of the vehicle. The block carries a revolvable casting 152 which is supported by the engagement of a shoulder or rabbet with a flange 153 on the block. Integral arms 154 on the casting support an horizontal pin 155, upon which is mounted a sleeve 156 capable of slight longitudinal movement and forming part of the bearing-block 27 which supports the reduced end of the transmission shaft 26, and the rods 129. The rods 129 are connected to the grooved boss of the wheel 24 by means of a split ring 131. In order to obtain a direct drive by further movement of the wheel 24 when in the maximum-speed position, this wheel is provided with a projecting conical flange 140 adapted for clutching engagement with a complementary member 141 in the driving-wheel 22. By this engagement the wheel 22 is moved back from the disks 21 against the pressure of the springs 36. Means are also provided for automatically withdrawing the disks 21 from the driven wheel 24 during this direct drive. To this end, the arm 122, Fig. 3, has a rigid extension 142, connected by a link 143 to the rocking-lever 144 pivoted on the pin 145 carried by an extension of the bracket 81. The lever 144 lies in line with the roller 111 of the locking-pawl 88 and is so arranged that, when the hand-lever 120 rocks the link 122 to bring the direct drive into operation, the forward end of the lever 144 bears against the roller 111 and swings the pawl out of engagement, whereupon the disks 21 are drawn back as previously described. Furthermore, the arrangement shown provides that, when the brakes are operated, the roller 110 in addition to releasing the ratchet 88 depresses the adjacent end of the rocking lever 144 so that if the hand-lever is released from its locking-mechanism the link-work is operated to disengage the clutch parts 140, 141 to disconnect the direct driver