| 摘要 |
1291802 Adjustable chairs; resilient seat mountings MODERN TUBE S A 26 April 1971 [27 April 1970] 11425/71 Headings A4J and A4U A seat is fixed to a support member, which may be rotatable, and has a back-rest mounted on one end of an upright of which the lower end is slidable horizontally on the support member by a lever to adjust the distance of the back-rest from the seat. The support member may be spring-supported and vertically adjustable in a base. In the form shown, the seat of an office chair is fixed to a member 46 rigidly secured to the top of a tube 14 which is telescopically mounted in a stationary tube 13 in a housing 12 forming the top of a leg spider; the tube 14 is formed with a tapered groove 45 for engagement by a clamping roller 36 mounted in the top of the tube 13 and pressed into the groove by a lever 40 with screw-threaded stem to hold the seat at the required height. The tube 13 is mounted on a ball bearing 22 supported on spring 20 in the housing 12. The back-rest is mounted on the upper end of an upright 18 which has its lower end bent to slide horizontally in a guide 50 on the member 46, the bend of the member 18 being shaped to provide resilience. The sliding part of the member 18 is formed with teeth engaged by a toothed sector 60, with hand-lever 62, whereby the back-rest may be moved forwards and backwards. In a modification, Fig. 5 (not shown), the sector and rack are replaced by a forked tail of the lever 62 engaging a pin on the member 18; alternatively, a plain tail of the lever 62 may engage between two pins on the member 18. |
