| 摘要 |
1,110,379. Guiding webs transversely. ROCKFORD SERVO CORPORATION. 28 Oct., 1966 [25 Feb., 1966], No. 48521/66. Heading B6B. Apparatus for guiding a web transversely comprises a roller 10 rotatably mounted on a movable support 16, which is in turn mounted on a stationary support 18 by guide means 17. The guide means 17 allows the roller to be moved in an arcuate path about a centre of rotation C offset to one side of the roller 10, and includes arcuate guide bars 31, 32 on one of the supports 16 or 18 and followers attached to the other support 18 or 16. The means for moving the movable support 16 and roller 10 relative to the stationary support 18 comprises a fluid actuator 51 having its cylinder 52 mounted by a gimbal joint 55 to the stationary support 18 and its piston rod 54 connected by a gimbal joint 50 to the movable support 16. The fluid actuator control means comprises an adjustably positioned edge sensor 61 of the vacuum type having an opening 67 in a web support member 68. A servo-mechanism includes an hydraulic pump 71 which pumps fluid from a reservoir 73 into a four-way reversing valve 76 connected to both sides of the fluid cylinder 52. The position of the valve 76 is controlled by a pneumatic actuator 82, exhausted by a pump 85 via a three-way valve 92 and a vacuum tube 69 leading to the opening in the edge sensor 61. To enable automatic centering of the roller 10 prior to web feeding, a centering valve 91 is provided, which is brought into operation by the three-way valve 92. The valve 91 comprises a tube having an axial passage and a lateral part 95, and a valve member 96 mounted for movement along the tube to control the flow of air through the part 95. The tube is connected to the stationary support 18 and the valve member 96 to the movable support 16. |
