Patent Application
20120013162
1. Field of the Invention
The present invention relates to a chair, more particularly to a drummer's chair.
2. Description of the Prior Art
Drummer's chairs are provided for drummers. These chairs are usually height-adjustable, just as the chair shown in U.S. Pat. No. 5,738,326. The chair mainly includes a threaded stem and a clamping device. The clamping device surrounds the threaded stem. The clamping device may secure the threaded stem with a screw and a nut. To avoid sliding of the threaded stem, users usually firmly secure the nut with a very strong force. The force may probably destroy the thread of the screw or the nut, especially when the height of the chair has been adjusted for many times. Thus, the life time of the chair is limited.
The present invention is, therefore, arisen to obviate or at least mitigate the above mentioned disadvantages.
The main object of the present invention is to provide a chair, which is height-adjustable and durable.
To achieve the above and other objects, a chair for a drummer of the present invention includes a main rod, a pad, a first sleeve, a fixation element, a tube, a second sleeve and three racks.
The main rod has a top end, a threaded section and a bottom end. The threaded section connects the top end to the bottom end. The pad is disposed on the top end. The pad is adapted for a drummer to sit thereon. The first sleeve has an inner surface. A through hole is defined in the inner surface. The main rod is received in the first sleeve. The first sleeve has three first pivoting portions. Each first pivoting portion defines a first pivoting axial. Each first pivoting axial is perpendicular to the longitudinal direction of the main rod. The fixation element comprises a clamping portion, a linking rod, an axial rod, a threaded piece and a swaying member. The clamping portion is disposed on the first sleeve in a rotational operative relationship. The clamping portion has a threaded clamping surface. A penetrating hole is defined in the clamping surface. The penetrating hole and the through hole are coaxial. The main rod is received in the penetrating hole. The penetrating hole mates with the threaded section. The clamping portion has a first abutting portion and a second abutting portion. An opening is defined between the first abutting portion and the second abutting portion. The opening extends from one end of the clamping portion to the other end of the clamping portion. The opening communicates with the penetrating hole and the surrounding. The first abutting portion is formed with a first axial hole. The second abutting portion is formed with a second axial hole. The axial holes are coaxial. The linking rod is received in the axial holes. The axial rod is perpendicularly disposed on one end of the linking rod. The threaded piece is screwed on the other end of the linking rod. The swaying member is disposed between the axial rod and the first abutting portion. The swaying member is rotatable about the axial rod. The abutting portions are located between the threaded piece and the swaying member. The swaying member has an arcuate surface facing the first abutting portion. A first pressing point, a second pressing point and a third pressing point are defined on the arcuate surface. The second pressing point is located between the first pressing point and the third pressing point. Each pressing point defines a pressing distance. Each pressing distance is a distance between the axial rod and its corresponding pressing point. The pressing distance of the second pressing point is greater than the pressing distances of the others. The pressing distance of the third pressing point is greater than the pressing distance of the first pressing point. The tube is firmly disposed on the first sleeve. The bottom end being received in the tube. The tube is slidably received in the second sleeve. The second sleeve has three second pivoting portions. Each second pivoting portion defines a second pivoting axial. Each second pivoting axial is perpendicular to the longitudinal direction of the main rod. Each rack comprises a supporting pole and a linkage. Each supporting pole is rotatably disposed on one of the first pivoting portions about its corresponding first pivoting axial. Each linkage has a first end and a second end. Each first end is rotatably disposed on one of the second pivoting portions about its corresponding second pivoting axial. Each second end is rotatably disposed on one of the supporting poles.
The present invention will become more obvious from the following description when taken in connection with the accompanying drawings, which show, for purpose of illustrations only, the preferred embodiment(s) in accordance with the present invention.
Please refer to
The main rod 1 has a top end 11, a threaded section 12 and a bottom end 13. The top end 11 is adapted for a pad to be disposed thereon. The threaded section 12 connects the top end 11 to the bottom end 13. A radial direction is defined perpendicular to the main rod 1.
The pad 2 is disposed on the top end 11. The pad 2 may be disposed on the top end 11 in a rotational operative relationship. The pad 2 is adapted for a drummer to sit there on.
The first sleeve 3 has an inner surface 31. A through hole is defined in the inner surface 31. The main rod 1 is received in the first sleeve 3. The inner surface may be threaded for the threaded section 12 to mate therewith. The first sleeve 3 is formed with three first pivoting holes 33. Three first pivoting portions 32 are received in the first pivoting holes 33 respectively. Each first pivoting portion 32 may be a bolt or a rivet. Each first pivoting portion 32 defines a first pivoting axial in its longitudinal direction which is perpendicular to the longitudinal direction of the main rod 1. In other possible embodiments of the invention, the first pivoting portions 32 may be formed on the first sleeve 3 directly.
The fixation element 4 includes a clamping portion 41, a linking rod 42, an axial rod 43, a swaying member 44 and a threaded piece 45. The fixation element 4 may further include a spring 46. The clamping portion 41 is disposed on the first sleeve 3 in a rotational operative relationship. Preferably, the clamping portion 41 may be directly formed on the first sleeve 3. The clamping portion 41 has a threaded clamping surface 411. A penetrating hole is defined in the clamping surface 411. The main rod 1 is received in the penetrating hole, so that the penetrating hole and the through hole are coaxial. The penetrating hole mates with the threaded section 12. The clamping portion 41 has a first abutting portion 413 and a second abutting portion 414. An opening 412 is defined between the first abutting portion 413 and the second abutting portion 414. The opening 412 extends from one end of the clamping portion 41 to the other end of the clamping portion 41. The opening communicates with the penetrating hole and the surrounding. The first abutting portion 413 is formed with a first axial hole 415. The second abutting portion 414 is formed with a second axial hole 416. The first axial hole 415 and the second axial hole 416 are coaxial. The first axial hole 415 and the second axial hole 416 are perpendicular to the longitudinal direction of the main rod 1. The first abutting portion 413 is formed with a slant surface 417 in the first axial hole 415, as shown in
The linking rod 42 is received in both of the axial holes 415, 416. The width along the radial direction of each axial hole is greater than the diameter of the linking rod 42, so that the linking rod 42 is movable along the radial direction. The axial rod 43 is perpendicularly disposed on one end 421 of the linking rod 42. The threaded piece 45 is screwed on the other end 422 of the linking rod 42.
The swaying member 44 is disposed between the axial rod 43 and the first abutting portion 413, so that the abutting portions 413, 414 are located between the swaying member 44 and the threaded piece 45. The swaying member 44 is rotatable about the axial rod 43. The swaying member 44 has an arcuate surface 441 facing the first abutting portion 413, as shown in
The distance between the axial rod 43 and the arcuate surface 441 is not uniform. Thus, a first pressing point, a second pressing point and a third pressing point can be defined on the arcuate surface 441. Each pressing point defines a pressing distance between itself and the axial rod 43. The second pressing point is located between the first pressing point and the third pressing point. The pressing distance of the second pressing point is greater than the pressing distances of the others. The pressing distance of the third pressing point is greater than the pressing distance of the first pressing point.
The spring 46 is disposed between the threaded piece 45 and the second abutting portion 414. Preferably, the spring 46 may be received in the large diameter section 4161, and may abut against the step surface 418.
The tube 5 is firmly disposed on the first sleeve 3. The bottom end 13 is received in the tube 5. The main rod 1 is slidable and rotatable with respect to the tube 5. The tube 5 may include a stretching section 51 and a stopping section 52. The stretching section 51 connects the first sleeve 3 to the stopping section 52. The outer diameter of the stopping section 52 is greater than the outer diameter of the stretching section 51.
The tube 5 is slidably received in the second sleeve 6. More specifically, the stretching section 51 is slidably received in the second sleeve 6. The stopping section 52 can block the second sleeve 6, so that the second sleeve 6 can not depart from the tube 5. The second sleeve 6 is formed with three second pivoting holes 62. Three second pivoting portions 61 are received in the second pivoting holes 62 respectively. Each second pivoting portion 61 may be a bolt or a rivet. Each second pivoting portion 61 defines a second pivoting axial in its longitudinal direction which is perpendicular to the longitudinal direction of the main rod 1. In other possible embodiments of the invention, the second pivoting portions 61 may be formed on the second sleeve 6 directly. The second sleeve 6 and the tube 5 may be secured by a screw 63, so that the position of the second sleeve 6 is adjustable.
Each rack 7 includes a supporting pole 71 and a linkage 72. Each supporting pole 71 is disposed on one of the first pivoting portions 32. Each supporting pole 71 is rotatable about its corresponding first pivoting axial. Each linkage 72 has a first end 721 and a second end 722. Each first end 721 is disposed on one of the second pivoting portions 61. Each first end 721 is rotatable about its corresponding second pivoting axial. Each second end 722 is rotatably disposed on one of the supporting poles 71.
Accordingly, the chair can be folded by moving the second sleeve 6. Also, the height of the pad 2 is adjustable. The swaying member 44 and the threaded piece 45 can be release, as shown in
To conclude, the chair can be secured by rotating the swaying member 44 rather than screwing a threaded element.
