US 4,082,244 A · Counterbalancing supporting device

Abstract

A device for supporting an object such as a dental x-ray unit on the free end of a vertically pivotal arm, which allows the object to be counterbalanced for stabilized vertical positioning. The supporting device includes a rigid tubular encasement having a pair of articulating knuckles pivotably attached at each end of the encasement, and a counterbalancing mechanism disposed within the encasement and connected at each end to the articulating knuckles, the counterbalancing mechanism including a compression spring having a force adjustment means, a rod disposed through said spring which includes a threaded fastener which engages one end of the compression spring, and linkage arms at each end connecting the rod to the articulating knuckles. The device is characterized by a readily accessible spring tension adjustment allowing job site adjustment to compensate for spring fatigue, improved efficiency and reduced costs resulting from a reduced number of operating parts, and improved operability.

Claims6

Dependent claims

A counterbalanced article supporting device to provide vertical adjustment of the supported article which upon release provides a stabilized fixed position of the article comprising:

rigid, tubular encasement;
first and second knuckles pivotably connected to opposite ends of said encasement;
compression spring disposed within said encasement;
spring stop connected to one end of said spring and to said encasement;
a rod partially disposed within said spring;
a block threadably connected to one end of said rod;
a moveable first linkage arm pivotally connected at one end to said block and pivotally at its opposite end to said first knuckle;
a clevis threadably connected to the opposite end of said rod;
a clevis bearing coupled to said clevis and connected to said encasement;
a movable second linkage arm pivotally connected at one end to said clevis and pivotally to said second knuckle at its opposite end;
adjustable spring tensioning means connected to said rod and engaging one end of said spring;
said encasement having an aperture in close proximity to said tensioning means, whereby said tensioning means is adjustably accessible from outside said encasement.

9 more elements

Dependencies are inferred from the claim text.

Counterbalancing supporting device

Life of this patent

Counterbalancing supporting device

Life of this patent

Abstract

Claims6