This application claims priority of Taiwanese Application No. 103110140, filed on Mar. 18, 2014.
The disclosure relates to a chair, more particularly to a foldable chair.
A foldable chair may be configured as a walking stick chair for use of people having inferior physical condition. Taiwanese Patent Application No. 102112330 discloses a conventional walking stick chair including a stick and a sleeve that is slidable along the stick. The conventional walking stick chair is convertible between a folded state and an unfolded state by moving the sleeve along the stick. The sleeve can be positioned relative to the stick for retaining the conventional walking stick chair in the folded or unfolded state. However, positioning of the sleeve relative to the stick can only indirectly keep a support leg of the conventional walking stick chair in folded or unfolded state. That is, the support leg may not be retained steadily at a predetermined position relative to the stick when the sleeve is positioned.
Therefore, the object of the present disclosure is to provide a foldable chair that can overcome the aforesaid drawbacks associated with the prior art.
Accordingly, a foldable chair of the present disclosure includes a main stick, a fold unit, a seat unit and a retention unit. The main stick includes a rod body that extends along an axis. The seat unit is connected to the rod body. The fold unit includes a middle slider member and a leg unit. The middle slider member is movable along the rod body between a lower position and an upper position that is located above the lower position. The leg unit includes at least one support leg that includes an upper leg component connected pivotally to the middle slider member, a lower leg component connected pivotally to the upper leg component, and a drive link having opposite ends that are connected respectively and pivotally to the seat unit and the upper leg component. The seat unit is operable to drive movement of the drive link so as to convert the fold unit between an unfolded state where a free end of the lower leg component is distal from the rod body and the upper leg component, and a folded state where the free end of the lower leg component is proximate to the rod body and the upper leg component, such that when the fold unit is converted from the unfolded state into the folded state, the free end of the lower leg component pivots toward the upper leg component. The retention unit includes at least one locking structure that includes a latch member, a pull cord and a block member. The latch member is connected movably to the upper leg component. The pull cord has a first end portion that is connected to the latch member, and a second end portion that is opposite to the first end portion and that is connected to the middle slider member. The block member is connected co-movably to the lower leg component, and has a pivot axis about which the lower leg component is pivotable relative to the upper leg component, a contact surface that extends around the pivot axis, and an engaging surface that is connected to the contact surface. A distance between the engaging surface and the pivot axis is smaller than that between the contact surface and the pivot axis. When the middle slider member is at the lower position and the fold unit is in the unfolded state, the latch member abuts against the engaging surface for preventing the lower leg component from pivoting relative to the upper leg component so as to keep the support leg unfolded. When the middle slider member is moved to the upper position, the pull cord is configured to be driven to separate the latch member from the engaging surface for permitting the lower leg component to pivot relative to the upper leg component so as to permit conversion of the fold unit from the unfolded state to the folded state.
Another object of the present disclosure is to provide a locking structure.
Accordingly, a locking structure of the present disclosure is used in a foldable linkage unit. The linkage unit includes pivotally-interconnected first and second links. The locking structure includes a latch member and a block member. The latch member is connected movably to the first link. The block member is connected co-movably to the second link, and has a pivot axis about which the second link is pivotable relative to the first link, a contact surface that extends around the pivot axis, and an engaging surface that is connected to the contact surface. A distance between the engaging surface and the pivot axis is smaller than that between the contact surface and the pivot axis. The latch member is operable to abut against the engaging surface for preventing the second link from pivoting relative to the first link, and to be separated from the engaging surface for permitting the second link to pivot relative to the first link.
Other features and advantages of the present disclosure will become apparent in the following detailed description of the embodiment with reference to the accompanying drawings, of which:
As shown in
Referring further to
The seat unit 4 includes a seat member 41 and an upper slider member 3.
The upper slider member 3 is movable along the rod body 10.
The seat member 41 includes a main plate 411 that has a proximal end portion 413 connected pivotally to the upper slider member 3, and a distal end portion 414 opposite to the proximal end portion 413, two lateral plates 412 that are connected respectively and pivotally to opposite lateral sides of the main plate 411, and a resilient hook 415 that is disposed at a bottom side of the main plate 411 and that is proximate to the distal end portion 414 of the main plate 411.
The fold unit 2 includes a middle slider member 21, a lower slider member 22, a connecting rod 23 (see
The middle slider member 21 is disposed under upper the slider member 3, is movable along the rod body 10 between a lower position (see
The slider resilient member 24 is configured as a tension spring, and connected between the middle slider member 21 and the upper slider member 3 for biasing resiliently the middle and the upper slider members 21, 3 toward each other. Each of the middle slider member 21 and the upper slider member 3 has a portion engaging movably the guide groove 11 of the rod body 10.
The leg unit 5 includes two support legs each including an upper leg component 51 that is connected pivotally to the middle slider member 21 by a pivot pin 511 (see
The fold unit 2 is operable to convert between an unfolded state where the upper slider member 3 and the middle slider member 21 are proximate to each other and where a free end of the lower leg component 52 of each of the support legs is distal from the rod body 10 and the corresponding upper leg component 51 (see
The seat unit 4 further includes two fold bars 42 and two linking bars 43.
Each of the fold bars 42 has opposite ends connected respectively and pivotally to the middle slider member 21 and a respective one of the lateral plates 412 of the seat member 41. Each of the linking bars 43 has opposite ends connected respectively and pivotally to the upper slider member 3 and a respective one of the fold bars 42.
Referring to
The cord seat 61 is disposed movably on the middle slider member 21, is disposed below the limiting member 12, and is movable relative to the middle slider member 21 in the longitudinal direction (L) of the rod body 10 between a released position (see
The seat resilient member 62 is configured as a compression spring, and is connected between the middle slider member 21 and the cord seat 61 for biasing resiliently the cord seat 61 to move upwardly relative to the middle slider member 21 toward the released position.
Each of the locking structures includes a latch member 63, a pull cord 64, a block member 65, a latch resilient member 66 and an installation seat 67. For simplification, one of the locking structures and the corresponding support leg thereof will be described in the following.
The installation seat 67 is connected fixedly to the upper leg component 51 and is formed with a limiting groove 671 that has two opposite closed ends.
The latch member 63 is connected movably to the upper leg component 51, and has an abutment surface 631 and a plate portion 632. The plate portion 632 is movable within the limiting groove 671 of the installation seat 67 between the two closed ends so as to limit the relative movement between the latch member 63 and the upper leg component 51.
The pull cord 64 has a first end portion that is connected to the latch member 63, and a second end portion that is opposite to the first end portion and that extends around the pivot pin 511 (see
The block member 65 is connected co-movably to the lower leg component 52, and has a pivot axis 651 about which the lower leg component 52 is pivotable relative to the upper leg component 51, a contact surface 652 that extends around the pivot axis 651, and an engaging groove that is formed in the contact surface 652. The block member 65 further has a groove-defining surface that defines the engaging groove, and that has a bottom surface portion connected to the contact surface 652 and serving as an engaging surface 653. A distance between the engaging surface 653 and the pivot axis 651 is smaller than that between the contact surface 652 and the pivot axis 651. In this embodiment, the contact surface 652 of the block member 65 is configured as an arc surface that is centered at the pivot axis 651 of the block member 65.
The latch resilient member 66 is connected between the latch member 63 and the upper leg component 51 for biasing resiliently the latch member 63 toward the block member 65. In this embodiment, the latch resilient member 66 of each of the locking structures is configured as a compression spring.
Referring to
To fold the foldable chair of this disclosure, the upper slider member 3 is moved upwardly relative to the main stick 1. It is noted that the middle and lower slider members 21, 22, the connecting rod 23, the upper and lower leg components 51, 52 and the auxiliary link 53 cooperatively form a four-bar linkage that has only one degree of freedom. Since the upper and lower leg components 51, 52 are prevented from pivoting relative to each other, the upward movement of the upper slider member 3 drives movement of the middle slider member 21 from the lower position toward the upper position via the drive link 54 and the upper leg component 51 while the fold unit 2 is kept unfolded.
Referring to
During conversion of the fold unit 2 from the unfolded state to the folded state, the upper slider member 3 drives the fold bars 42 to pivot toward the rod body 10 via the linking bars 43, and the end of each of the fold bars 42 connected to the corresponding lateral plate 412 slides along a guide groove formed in the corresponding lateral plate 412. When the fold unit 2 is at the folded state, the main plate 411 and the lateral plates 412 cooperatively form a U-shaped structure to cover the support legs 12 of the fold unit 2.
Referring to
To unfold the foldable chair, the upper slider member 3 is operated to disengage from a positioning groove 13 formed in the rod body 10, and is moved downwardly to drive the middle slider member 21 to move downwardly.
When the middle slider member 21 is moved away from the upper position, the cord seat 61 is spaced apart from the limiting member 12 and is biased by the seat resilient member 62 to move upwardly relative to the middle slider member 21 so as to disengage the hook groove 68 from the resilient hook 45 and to permit conversion of the fold unit 2 between the unfolded state and the folded state. Meanwhile, the latch resilient member 66 biases the latch member 63 to abut against the block member 65. In this embodiment, the abutment surface 631 of the latch member 63 is in line contact with the contact surface 652 of the block member 65 when the support leg is folded and when the middle slider member 21 is moved away from the upper position.
The advantages of this disclosure are as follows.
1. The latch member 63 of each of the locking structure is configured to prevent the relative pivot movement between the upper and lower leg components 51, 52 of the corresponding support leg directly.
2. By virtue of the configuration of the retention unit 6, the relative pivot movement between the upper and lower leg components 51, 52 of each of the support legs can be permitted or prevented through moving the upper slider member 3 along the rod body 10 of the main stick 1 simply.
While the present disclosure has been described in connection with what is considered the most practical embodiment, it is understood that this disclosure is not limited to the disclosed embodiment but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.
Number | Date | Country | Kind |
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103110140 | Mar 2014 | TW | national |