ANGLE ADJUSTING/POSITIONING DEVICE FOR A BACKREST OF A CHAIR
An angle adjusting/positioning device includes first and second sleeves fixed to a backrest and a seat of a chair. The first sleeve has a first axle hole and a first toothed portion. A second sleeve includes a second axle hole, a second toothed portion, and a positioning portion. A third sleeve has a third axle hole and an actuating portion. An axle extends through the first, second, and third axle holes. A handle fixed to the third sleeve is operable to move the actuating portion relative to the positioning portion, causing the second toothed portion to engage with or disengage from the first toothed portion. An angular position of the backrest relative to the seat is adjustable when the second toothed portion disengages from the first toothed portion. The angular position of the backrest is fixed when the second toothed portion engages with the first toothed portion.
The present invention relates to an angle adjusting/positioning device for a backrest of a chair and, more particularly, to an adjusting device allowing easy operation in adjustment of an angular position of a backrest of a chair and providing reliable positioning for the backrest.
Conventional backrests of chairs are adjustable in angular positions to provide lying comfort. Conventional backrest adjusting devices generally include a chassis below the seat, with a lower end of the backrest coupled to the chassis that allows adjustment of the angular position of the backrest. However, the chassis is expensive and is not suitable for large chairs such as sofas and leisure chairs.
An objective of the present invention is to provide an adjusting device allowing easy operation in adjustment of an angular position of a backrest of a chair and providing reliable positioning for the backrest.
An angle adjusting/positioning device according to the present invention includes a first mounting seat adapted to be fixed to one of a backrest and a seat of a chair. The first mounting seat includes a first sleeve having a first axle hole. The first sleeve includes an end face having a first toothed portion. The angle adjusting/positioning device further includes a second mounting base adapted to be fixed to the other of the backrest and the seat of the chair. The second mounting base includes a second sleeve having a first side and a second side opposite to the first side. A second axle hole extends from the first side through the second side of the second sleeve. A second toothed portion is provided on the first side of the second sleeve and surrounds the second axle hole. The second sleeve further includes a positioning portion. An elastic element is mounted between the first and second sleeves. The elastic element biases the first and second toothed portions of the first and second sleeves to disengage from each other or engage with each other. A handle mechanism includes a handle seat having a third sleeve. A handle is fixed to the third sleeve. The third sleeve includes a third axle hole and an actuating portion. An axle extends through the third axle hole, the second axle hole, and the first axle hole of the handle seat, the second sleeve, and the first sleeve. The handle is operable to move the actuating portion relative to the positioning portion, causing the second toothed portion to engage with or disengage from the first toothed portion. An angular position of the backrest relative to the seat is adjustable when the second toothed portion disengages from the first toothed portion. The angular position of the backrest is fixed when the second toothed portion engages with the first toothed portion.
The present invention will become clearer in light of the following detailed description of illustrative embodiments of this invention described in connection with the drawings.
With reference to
The second mounting base 2 includes a second sleeve 21 having a first side 27 and a second side 28 opposite to the first side 27. The second sleeve 21 further includes an outer periphery extending between the first and second sides 27 and 28. A tab 22 is provided on the outer periphery of the second sleeve 21. The tab 22 is engaged in a receiving hole 71 in a rear end of the seat 7. A second axle hole 23 extends from the first side 27 through the second side 28 of the second sleeve 2. A second toothed portion 24 is provided on the first side 27 of the second sleeve 21 and surrounds the second axle hole 23. The second axle hole 23 includes a second compartment 25 in the first side 27 and surrounded by the second toothed portion 24 in the form shown. A positioning portion 26 is formed on the second side 28 of the second sleeve 21 and surrounds the second axle hole 23. In the form shown, the positioning portion 26 includes two diametrically opposed first positioning grooves 261 and two diametrically opposed second positioning grooves 262. Each of the first and second positioning grooves 261 and 262 includes a bottom wall. A spacing between the bottom wall of each first positioning groove 261 to the second side 28 of the second sleeve 21 is larger than a spacing between the bottom wall of each second positioning groove 262 and the second side 28 of the second sleeve 21. An inclined surface 265 extends between each first positioning groove 261 and a corresponding second positioning groove 262. The positioning portion 26 further includes a first stop wall 263 extending perpendicularly to the bottom wall of each first positioning groove 262, with the bottom wall of the first positioning groove 262 located between the inclined surface 265 and the first stop wall 263. Furthermore, the positioning portion 26 further includes a second stop wall 264 extending perpendicularly to the bottom wall of each second positioning groove 262, with the bottom wall of the second positioning groove 262 located between the inclined surface 265 and the second stop wall 264. However, the positioning portion 26 can include only one first positioning groove 261, only one second positioning groove 262, and only one inclined surface 265.
The first toothed portion 14 of the first sleeve 11 engages with the second toothed portion 24 of the second sleeve 21, with the first axle hole 13 aligned with the second axle hole 23, with the first compartment 15 of the first axle hole 13 facing and aligned with the second compartment 25 of the second axle hole 23. The elastic element 3 is received in the first and second compartments 15 and 25 of the first and second axle holes 13 and 23. The elastic element 3 provides elastic force for operation of the first and second mounting bases 1 and 2. In the form shown, the elastic element 3 biases the first and second toothed portions 14 and 24 of the first and second mounting bases 1 and 2 to disengage from each other.
The handle mechanism 4 includes a handle seat 41 having a third sleeve 411. The third sleeve 411 includes a first face 417 and a second face 418 opposite to the first face 417. The third sleeve 411 further includes an outer periphery extending between the first and second faces 417 and 418. A tab 412 is provided on the outer periphery of the third sleeve 411. A handle 42 is fixed to the tab 412. A third axle hole 413 extends from the first face 417 through the second face 418. The third axle hole 413 includes an actuating portion 414 in the form shown having a receiving groove 415 in the first face 417 for receiving the positioning portion 26. This provides an aesthetically pleasing appearance. The receiving groove 415 includes a wall having two positioning members 416 each of which is selectively engaged in one of the first and second positioning grooves 261 and 262. However, the receiving groove 415 can include only one positioning member 416.
The axle 5 is extended through the third, second, and first axle holes 413, 23, and 13 of the handle seat 41, the second sleeve 21, and the first sleeve 11, with a bolt 51 fixed to an end of the axle 5 to position the axle 5.
The handle 42 can be operated to cause engagement or disengagement between the first and second toothed portions 14 and 24 of the first and second sleeves 11 and 21. When each positioning member 416 of the handle seat 41 is in the first positioning groove 261, the positioning member 416 can abut against the first stop wall 263 to cause engagement of the first and second toothed portions 14 and 24. The elastic element 3 is compressed to fix the angular position of the backrest 6, as shown in
With reference to
By providing the first and second toothed portions 14 and 24, the angle adjusting/positioning device according to the present invention is more reliable than conventional clamping. The first and second mounting bases 1 and 2 can be pivotably connected to the backrest 6 and the seat 7 by other provisions. Furthermore, the first and second mounting bases 1 and 2 can be coupled with the seat 7 and the backrest 6, respectively.
Although specific embodiments have been illustrated and described, numerous modifications and variations are still possible without departing from the essence of the invention. The scope of the invention is limited by the accompanying claims.
Claims
1. An angle adjusting/positioning device for a backrest of a chair, with the angle adjusting/positioning device comprising:
- a first mounting seat adapted to be fixed to one of a backrest and a seat of a chair, with the first mounting seat including a first sleeve having a first axle hole, with the first sleeve including an end face having a first toothed portion;
- a second mounting base adapted to be fixed to another of the backrest and the seat of the chair, with the second mounting base including a second sleeve having a first side and a second side opposite to the first side, with a second axle hole extending from the first side through the second side of the second sleeve, with a second toothed portion provided on the first side of the second sleeve and surrounding the second axle hole, with the second sleeve further including a positioning portion;
- an elastic element mounted between the first and second sleeves, with the elastic element biasing the first and second toothed portions of the first and second sleeves to disengage from each other or engage with each other;
- a handle mechanism including a handle seat having a third sleeve, with a handle fixed to the third sleeve, with the third sleeve including a third axle hole and an actuating portion; and
- an axle extending through the third axle hole, the second axle hole, and the first axle hole of the handle seat, the second sleeve, and the first sleeve, with the handle operable to move the actuating portion relative to the positioning portion, causing the second toothed portion to engage with or disengage from the first toothed portion, with an angular position of the backrest relative to the seat being adjustable when the second toothed portion disengages from the first toothed portion, with the angular position of the backrest being fixed when the second toothed portion engages with the first toothed portion.
2. The angle adjusting/positioning device as claimed in claim 1, with the positioning portion formed on the second side of the second sleeve, with the positioning portion including first and second positioning grooves each having a bottom wall, with a spacing between the bottom wall of the first positioning groove to the second side of the second sleeve being different from a spacing between the bottom wall of the second positioning groove to the second side of the second sleeve.
3. The angle adjusting/positioning device as claimed in claim 2, with the spacing between the bottom wall of the first positioning groove to the second side of the second sleeve being larger than the spacing between the bottom wall of the second positioning groove to the second side of the second sleeve, with an inclined surface extending between the first positioning groove and the second positioning groove.
4. The angle adjusting/positioning device as claimed in claim 3, with the actuating portion of the handle seat including a receiving groove receiving the positioning portion, with the receiving groove including a wall having a positioning member, with the positioning member selectively engaged in one of the first and second positioning grooves to engage the second toothed portion with the first toothed portion or to disengage the second toothed portion from the first toothed portion.
5. The angle adjusting/positioning device as claimed in claim 1, with the first axle hole including a first compartment in the end face of the first sleeve, with the second axle hole including a second compartment in the first side, with the elastic element received in the first and second compartments.
6. The angle adjusting/positioning device as claimed in claim 5, with the first sleeve of the first mounting base including a first tab on an outer periphery thereof, with the first tab adapted to be engaged with a lower end of the backrest, with the second sleeve of the second mounting base including a second tab on an outer periphery thereof, with the second tab adapted to be engaged with a rear end of the armrest, with the third sleeve of the handle seat including a third tab on an outer periphery thereof, with the handle fixed to the third tab.
7. The angle adjusting/positioning device as claimed in claim 6, with the chair including a guiding rod having a lower end connected to the base and an upper end connected to a front end of the armrest, with the seat including a side having a receiving portion, with the guiding rod received in the receiving portion, with the lower end of the backrest including a first receptacle receiving the first tab, with the rear end of the backrest including a second receptacle receiving the second tab.
Type: Application
Filed: May 27, 2012
Publication Date: Nov 28, 2013
Inventor: Chang Chen Lin (Tainan County)
Application Number: 13/481,838