GB277805A - Improvements in or relating to means for arresting rapid-runing heavy machines - Google Patents

Abstract

277,805. Gimson Shoe Machinery Co., Ltd., Bagshaw, C. M., and Choice, F. C. Sept. 27, 1926. Periodic.-A stop mechanism for rapid-running heavy machines comprises a friction brake actuated and controlled by the momentum of the machine parts, which, on operation of the usual starting and stopping pedal, automatically exerts first an initial unverying braking force which is insufficient to arrest the machine and then exerts all increasing force until the machine is arrested in a predetermined position. One end of the brake band 19 is linked to a stud 15 journaled in the machine and provided eccentrically with a pin 17 connected by a link 18 with a pin 20 in the other end of the band. Secured to the stud 15 is the boss of an elbow lever 6, one arm of which is connected at 5 to a slide housing 4 provided with a slide-block 7. A rocking-lever 26 is pivoted at 27 and carries a cam roll 25 engaging a cam track 24 in the brake drum so that the lever is continuously rocked while the machine is in motion. The lower end of the lever 26 is provided with a bearing to receive a block 41, from one side of which projects a tumbler 28. When the machine is started the rod 1 connected to the clutch treadle is moved downwardly and by means of a block 3 thereon moves the slide housing 4 about its pivot 5. The tumbler 28 is swung downwardly by frictional engagement with a spring-pressed abutment 11 in the slide-block 7, until they disengage when the tumbler returns to horizontal position and the slide block 7 is advanced by a spring plunder 10 as far as adjustable stop nuts 8 allow; also the lever 6 is swung against adjustable stop nuts 23 by a spring 22 to release the brake, and swings the slide housing 4 forwardly. When the machine is stopped by the release of the treadle the housing 4 is moved up by the block 3 and as the housing 4 and the slide block 7 are in their most advanced position the abutment 11 engages the underface of the tumbler 28 which is moved by the rocking-lever 26 to engage the front face of the slide-block 7 and thus apply the brake by means of the spring plunger 10 and the lever 6. The slide-block 7 is retained by a spring- pressed latch 30 engaging a lug 14<a> so that the brake band exerts an unvarying pressure, whilst the tumbler 28 is moved away by the lever 26, so that the abutment 11 resumes its normal position and when the tumbler 28 is again advanced it engages the side of the abutment 11 and moves this and the slide-block 7 further so that a lug 43 on the slide-block engages an adjustable stop 9 in the housing 4 and applies unyielding pressure to apply the brake which pressure increases until the machine is arrested. The degree of unvarying pressure may be adjusted by adjusting the spring 10 by means of a stud.