Chair for dental patients
First Claim
1. In a chair for a dental patient comprising a chair substructure containing a support frame, a superstructure containing a seat having a seat frame, a back rest, means for pivotally hinging the back rest to the seat, displacement means being disposed between the support frame and the seat frame including a straight line mechanism for shifting the seat frame between a first position with the seat being substantially level and a second position with the seat moved the maximum amount from the first position, control means for controlling the inclination of the back rest as the seat moves between the first position and second position, said control means holding the back rest in an upright position when the seat is in the first position and tilting the back rest as the seat moves toward the second position, and means for tilting the seat as it moves from the first position toward the second position, the improvements comprising the means for pivotally hinging the back rest to the seat including a pivotal bearing having a first pivot axis approximately in the area of the hip joint of a person sitting in the chair, said pivotal bearing including a bearing part rigidly connected to the back rest, said control means comprising a first lever arm mounted for pivotal movement on a second pivot axis on the seat frame, a second lever arm mounted for pivotal movement on said second pivot axis and rigidly connected to move with the first arm, a projection on the bearing part of the back rest extending into the seat adjacent the seat frame, and a tie rod connecting an end of said projection to the first arm, said second arm having a roller riding on a track disposed on the support frame so that the second and first arms pivot around their connection as the seat frame moves from the first position toward the second position to allow the back rest to pivot on the first pivot axis.
1 Assignment
0 Petitions
Accused Products
Abstract
A dental chair having a support frame, a seat with a seat frame, a back rest pivotally connected to the seat and a displacement device for moving the seat frame on the support frame with tilting of the seat and an arrangement for controlling the inclination of the back rest, characterized by the pivotal connection between the seat comprising a separate pivoting bearing on each side having a pivot axis approximately in the area of the hip joint of a person sitting in the chair and the arrangement for controlling the inclination of the back rest comprising a one-piece member having two lever arms being pivotally connected on the side of the seat frame with one of the lever arms having a roller riding on the track on the support frame and the other lever arm being connected to a projection of a part of the pivoting bearing which is attached to the seat rest so that as the seat frame is moved between positions, the roller moving on the track enables the back to change its degree of inclination to the seat. The chair also includes an arrangement for tilting the seat which includes at least one pair of guide members which are inclined to each other by approximately 160° and are mounted in the seat frame, which guide members receive sleeves that are pivotally connected to the support frame.
31 Citations
17 Claims
- 1. In a chair for a dental patient comprising a chair substructure containing a support frame, a superstructure containing a seat having a seat frame, a back rest, means for pivotally hinging the back rest to the seat, displacement means being disposed between the support frame and the seat frame including a straight line mechanism for shifting the seat frame between a first position with the seat being substantially level and a second position with the seat moved the maximum amount from the first position, control means for controlling the inclination of the back rest as the seat moves between the first position and second position, said control means holding the back rest in an upright position when the seat is in the first position and tilting the back rest as the seat moves toward the second position, and means for tilting the seat as it moves from the first position toward the second position, the improvements comprising the means for pivotally hinging the back rest to the seat including a pivotal bearing having a first pivot axis approximately in the area of the hip joint of a person sitting in the chair, said pivotal bearing including a bearing part rigidly connected to the back rest, said control means comprising a first lever arm mounted for pivotal movement on a second pivot axis on the seat frame, a second lever arm mounted for pivotal movement on said second pivot axis and rigidly connected to move with the first arm, a projection on the bearing part of the back rest extending into the seat adjacent the seat frame, and a tie rod connecting an end of said projection to the first arm, said second arm having a roller riding on a track disposed on the support frame so that the second and first arms pivot around their connection as the seat frame moves from the first position toward the second position to allow the back rest to pivot on the first pivot axis.
- 10. In a chair for a dental patient comprising a chair substructure containing a support frame, a superstructure containing a seat having a seat frame, a back rest, means for pivotally hinging the back rest to the seat, displacement means being disposed between the support frame and the seat frame including a straight line mechanism for shifting the seat frame between a first position with the seat being substantially level and a second position with the seat moved the maximum amount from the first position, control means for controlling the inclination of the back rest as the seat moves between the first position and second position, said control means holding the back rest in an upright position when the seat is in the first position and tilting the back rest as the seat moves toward the second position, and means for tilting the seat as it moves from the first position toward the second position, the improvements comprising the means for pivotally hinging the back rest to the seat including a separate pivotal bearing on each side of the seat having a first pivot axis approximately in the area of the hip joint of a person sitting in the chair, each of said pivotal bearings including a part rigidly connected to the back rest, said control means comprising a pair of first lever arms mounted adjacent the sides of the seat frame for pivotal movement around a second pivot axis, a second lever arm mounted for pivotal movement on said second pivot axis and rigidly connected to move with the first arm, a projection on each of the bearing parts of the rear seat extending into the seat adjacent the seat frame, and a tie rod connecting said end of said projection to the first arm, said second arm having a roller riding on a track disposed on the support frame so that the second and first arms pivot around their pivot axis as the seat frame moves from the first position toward the second position to allow the back rest to pivot on the first pivot axis.
Specification