Stool for dentists

Abstract

Abstract 947,849. Hydraulically adjustable seats. VACUDENT MANUFACTURING CO. Oct. 12, 1962 [Oct. 13, 1961 (2); July 3, 1962], No. 38738/62. Heading B8J. [Also in Division A4] A stool comprises a platform base 13, a seat 10, extendible and retractable post structure 11, 12 rising from the base centrally thereof and supporting the seat 10, power means for extending the post to raise the seat, means such as a valve 34 controlling operation of the power means, and means for actuating the control means, the actuating means having a foot-operated portion 44 at least partially surrounding the post structure 11, 12 above the surface of the base 13. The post structure consists of a post 11 and tube 12 which together form an hydraulic assembly. A sleeve 15 is secured to the upper end of the tube 12. As shown in Fig. 4, the footoperated part of the actuating means consists of a ring 44 encircling the post structure. The actuating means also consists of a lever comprising a pair of rods 45 depending slidably through the base 13 from the ring 44, a bearing ring 47 slidable along the lower end of the post structure (Fig. 5) and a working arm 48 projecting from the ring 47. The arm 48 is secured to another lever arm 49 provided as part of valve 34 and pivoted at 50 to operate a spring-loaded plunger 35. The valve 34 is opened by pressure on the ring 44. This permits entrapped compressed air in a reservoir 32 to expand and force hydraulic fluid from this reservoir 32 into tube 12 to raise the seat 10 when the user takes his weight off the seat. A non-return valve 37 prevents fluid flow in the cylinder-reservoir direction. A bleeder passage 51 provides for gradual return of fluid to the reservoir 32 and thus a gradual lowering of the seat under the weight of the user when pressure is applied to the foot ring 44. The post is made in two parts 11, 11-1 so that the seat 10 can be raised independently of the power system. An abdominal rest 17 is provided which may be adjusted vertically, horizontally and rotatably relatively to the seat 10 by means of members 23, 21 and 29 respectively.

Inventors

• 👤 Elbert O Thompson
• 👤 Dean H Hale

Bibliographic Details