| 摘要 |
1,092,314. Hand brake; linkwork. VAUXHALL MOTORS Ltd. May 19, 1966 [June 12, 1965], No. 24909/65. Headings F2E and F2K. A lever mechanism hav ing a varying mechanics advantage, for providin quick initial take-up in vehicle braking system comprises an input lever 5 pivoted at C to an outpu actuator lever 56 itsel pivoted at O to a fixed bracket 60 and connected at Q to an output linkage, one arm 54 of the lever 50 being connected to the lever 56 by a yieldable link 58, and a link 66 connecting the input lever at A to a pawl lever 64 pivoted on " O " and carrying a locking pawl 68 which in one position of the mechanism can engage a fixed ratchet 62. The pawl 68 is held from the ratchet, in the brake release position shown, by the engagement of a pawl pin P with an abutment 72 on the output lever. During initial application the levers 50, 56 move as one about pivot 0, to effect initial quick take-up, until the link 58 yields, lever 50 then pivoting about C and link 66 moving the pawl lever 64 anti-clockwise relatively to the output lever 56 until pawl 68 is freed to engage the ratchet. Thereafter the pawl lever 64 is fixed and the mechanism acts as a four-bar chain BACO with BO fixed, to provide an increased mechanical advantage. Finally, the pivotal connection G 1 the line joining C and G 2 to provide an " over-centre " action to assist the final increment of movement of the lever 50 to the position where the brake is fully engaged. A hold-on pawl 74 pivoted to the output lever at J is releasable by a Bowden cable 80 connected to a release lever carried on the input brake arm 52. The output lever comprises two plates with the remainder of the mechanism disposed between. The input arm 52 may be movable by a servo device. |
