GB2517288A

GB2517288A - Joint device

Info

Publication number: GB2517288A
Application number: GB1411962.2A
Authority: GB
Inventors: Xiaosong Duan; Gu-Liang Yuan
Original assignee: Wonderland Nurserygoods Co Ltd Hong Kong
Current assignee: Wonderland Nurserygoods Co Ltd Hong Kong
Priority date: 2013-07-09
Filing date: 2014-07-04
Publication date: 2015-02-18
Anticipated expiration: 2034-07-04
Also published as: GB2517288B; DE102014109500A1; CN104273982B; TWI554690B; NL2013148A; GB201411962D0; NL2013148C2; CN104273982A; TW201508184A; DE102014109500B4

Abstract

A joint device for providing rotation between two mounting seats wherein the mounting seats have grooves such that a latch mechanism 3 can selectively engage them both at a specific orientation to prevent rotation and wherein a retention mechanism 4 is provided to hold the latch mechanism 3 in an unlocked position when moved there when the mounting seats are arranged at the specific alignment and release the latch 3 when the device is turned. The retention mechanism 4 may employ a hook arrangement 41 which can act to restrain a compression spring 6 which biases it and the latch mechanism 3 towards a locked position. The joint may have grooves arranged so that the latch 3 can only lock in selected positions and the latch 3 may move in a direction of the axis about which the joint rotates. The device is designed to make it easier to adjust a handle on a carry cot using one hand.

Description

JOINT DEVICE

The invention relates to a joint device, more particularlyto a joint device foruse inababybasket.

A conventional baby basket is used to carry an infant, and includes a basket, a handle, and a joint device that interconnects rotatably the basket and the handle. The handle can be locked relative to the basket at an unfolded position by the joint device, where a distal portion of the handle is distal from the basket. To fold the handle relative to the basket, a pushbutton of the joint device needs to be pressed constantly to unlock the handle, sllch that the handle can be rotated relative to the basket to a folded position, where the distal portion of the handle is close to the basket. The abovementioned operation needs to be achieved by both hands of a user, and is inconvenient for the user.

Therefore, the object of the present invention is to provide a joint device that canovercome the aforesaid

drawbacks associated with the prior arts.

Accordingly, a joint device of the present invention includes a first mounting seat, a secondmounting seat, alatchmember, anoperatingmemberandaretentionunit.

The first mounting seat is formed with at least one first locking groove. The second mounting seat is connected to the first mounting seat, is formed with at least one second locking groove, and is rotatable relative to the first mounting seat about a first axis. The second locking groove is aligned with the first locking groove in a direction of the first axis when the second mounting seat is at an unfolded position relative to the first mounting seat. The second locking groove is misaligned from the first locking groove when the second mounting seat leaves the unfolded position. The latch member has at least one latch portion, and is movable along the first axis between the first and secondmounting seats.

The latch portion of the latch member engages the first locking groove and the second locking groove to prevent the rotation of the second mounting seat relative to the first mounting seat when the latch member is at a locking position. The latch portion of the latch member engages the first locking groove and is disengaged from the second locking groove to permit the rotation of the second mounting seat relative to the first mounting seat when the latch member is at an unlocking position. The operating member is coupled to the latch member, and is capable of being driven to move along the first axis toward the first mounting seat to drive movement of the latch member from the locking position to the unlocking position so that the second mounting seat can leave the unfolded position. The retention unit is configured to hold the latch member at the unlocking position in response to the movement of the latch member driven by the operating member from the locking position to the unlocking position to permit the rotation of the second mounting seat relative to the first mounting seat when the second mounting seat is at the unfolded position.

Other features and advantages of the present lnventionwillbecomeapparent inthe followingdetailed description of the preferred embodiments with reference to the accompanying drawings, of which: Fig. lisaperspectiveviewofababybasket including a first preferred embodiment of a joint device according to the invention, illustrating that a second mounting seat is disposed at an unfolded position; Fig. 2isanotherperspectiveviewofthebabybasket, illustrating that the second mounting seat is disposed at a folded position; Fig. 3 is an exploded perspective view of the first preferred embodiment; Fig. 4 is a perspective view of the second mounting seat of the first preferred embodiment; Fig. 5 is a perspective view of a latch member of the first preferred embodiment; Fig. 6 is a fragmentary sectional view of the first preferred embodiment, illustrating the latch member in a locking position; Fig. 7 is another fragmentary sectional view of the first preferred embodiment, illustrating the latch member in an unlocking position; Fig. 8is a fragmentary perspective view of the first preferred embodiment in which the second mounting seat is omitted; Fig. 9 is another fragmentary perspective view of the first preferred embodiment in which the second mounting seat and the latch member are omitted; Fig. 10 is an exploded perspective view of a second preferred embodiment of the joint device according to the invention; Fig. 11 is another exploded perspective view of the second preferred embodiment; Fig. 12 is a fragmentary sectional view of the second preferred embodiment, illustrating a latch member at a locking position; Fig. 13 is another fragmentary sectional view of the second preferred embodiment, illustrating the latch member being held at an unlocking position; Fig. 14 is anexplodedperspectiveviewillustrating a retention unit of the second preferred embodiment; Fig. 15 is a fragmentary sectional view of the second preferred embodiment, illustrating the retention unit holding the latch member at an unlocking position; Fig. 16 is a schematic perspective view of a third preferred embodiment of the joint device according to the invention; Fig. 17 is a fragmentary sectional view of the third preferred embodiment, illustrating a latch member at a locking position; and Fig. 18 is another fragmentary sectional view of the third preferred embodiment, illustrating the latch member being held at an unlocking position.

Before the present invention is described in greater detail, it shouldbe notedthat like elements are denoted by the same reference numerals thrcughcut the

disclosure.

Referring to Figs. 1 and 2, a baby basket is shown to include a basket la, a handle lb, and two first preferred embodiments of joint devices 100 according to the present invention that interconnect rotatably the basket la and the handle lb. Referring further to Figs. 3 to 9, the first preferred embodiment includes a first mounting seat 1, a second mounting seat 2, a latch member 3, a retenticn unit 4, an operating member 5, a first resilient member 6 and a second resilient member 7.

The first mounting seat 1 has a first mounting segment that is mounted with the basket ía, and a first shaft segment 13 that extends along a first axis (A) (see Fig. 6) . The second mounting seat 2 has a seoond mounting segment 20 that is mounted with the handle 1±, and a second shaft segment 23 that extends along the first axis (A) (see Fig. 6), that is conneoted to and inserted into the first shaft segment 13, and that is rotatable relative to the first shaft segment 13 about the first axis (A) , such that the second mounting seat 2 is rotatable relative to the first mounting seat 1 about the first axis (A) between an unfolded position (see Fig. 1) and a folded position (see Fig. 2) . A distal portion of the handle lb is distal from the basket la when the secondmounting seat is at the unfoldedposition, and is close to the basket la when the second mounting seat is at the folded position.

The first mounting seat 1 is formed with two first locking grooves 11 that are opposite to each other in a direction perpendicular to the first axis (A) , and a plurality of first auxiliary locking grooves 12. The first locking grooves 11 and the first auxiliary locking grooves 12 are angularly-arranged about the first axis (A).

The second mounting seat 2 is formed with two second locking grooves 21 that are opposite to each other in a direction perpendicular to the first axis A) , and a plurality of second auxiliary locking grooves 22. The second locking grooves 21 and the second auxiliary locking grooves 22 are angularly-arranged about the first axis (A) . Each of the second locking grooves 21 is aligned with a respective one of the first locking grooves 11 in the direction of the first axis (A) when the second mounting seat 2 is at the unfolded position, and is misaligned from the respective one of the first locking grooves 11 in the direction of the first axis (A) when the second mounting seat 2 leaves the unfolded position. Each of the second auxiliary locking grooves 21 is alignedwitha respective one of the first auxiliary locking grooves 11 in the direction of the first axis (A) when the second mounting seat 2 is at the unfolded position, and is misaligned from the respective one of the first auxiliary locking grooves 11 in the direction of the first axis (A) when the second mounting seat 2 leaves the unfolded position. The second mounting seat 2 is further formed with a plurality of extension holes 2a and a plurality of communication holes 2b (see Fig. 4) . In this embodiment, the extension holes 2a and the communication holes 2b are arranged alternately and angularly about the first axis (A) The latch member 3 has a circular body 33 that is centered at the first axis (A) , two latch portions 32 that are opposite to each other in a direction perpendicular to the first axis (A) , and a plurality of auxiliary latch portions 31. The latch portions 32 and the auxiliary latch portions 31 are disposed on a periphery of the circular body 33.

The latch member 3 is disposed movably between the first and second mounting seats 1, 2. The circular body 33 of the latch member 3 is formed with a through hole 3b for extension of the first and second shaft segments 13, 23 of the first and second mounting seats 1, 2. The latchmember3ismovablealongthefirstaxis (A) between alockingposition (see Fig. 6) and anunlockingposition (see Fig. 7) when the second mounting seat 2 is at the

B

unfolded position.

When the latch member 3 is at the locking position, each of the latch portions 32 of the latch member 3 engages a respective one of the first locking grooves 11 and the respective one of the second locking grooves 21 aligned with the respective one of the first locking grooves 11 to prevent the rotation of the secondmounting seat 2 relative to the first mounting seat 1, and each of the auxiliary latch portions 31 of the latch member 3engagesarespectiveoneofthefirstauxiliarylocking grooves 12 and the respective one of the second auxiliary locking grooves 22 aligned with the respective one of the first auxiliary locking grooves 12.

When the latch member 3 is at the unlocking position, eachofthelatchportions32ofthelatchmember3engages the respective one of the first locking grooves 11 and is disengaged from the respective one of the second looking grooves 21 to permit the rotation of the second mounting seat 2 relative to the first mounting seat 1, and each of the auxiliary latch portions 31 of the latch member 3 engages the respective one of the first auxiliary locking grooves 12 and is disengaged from the respective one of the second auxiliary locking grooves 22. Each of the first and second auxiliary locking grooves 12, 22 has a dimension smaller than that of each of the latch portions 32 of the latch member 3 to prevent the latch portions 32 from being engaged therewith when the second mounting seat 2 leaves the unfolded position.

The operating member 5 is movable along the first axis (A) , is co-rotatable with the second mounting seat 2, and has a button portion 51 that is disposed at one side of the second mounting seat 2 opposite to the latch member 3, and a plurality of rod portions 52, each of which extends from a periphery of the button portion 51 and through a respective one of the extension holes 2a in the direotion of the first axis (A) . The button portion 51 of the operating member 5 is capable of being pressed to move toward the first mounting seat 1 to drive the rod portions 52 to push the latoh member 3, and to drive movement of the latch member 3 from the locking position to the unlocking position when the seoond mounting seat 2 is at the unfolded position.

The first resilient member 6 has opposite ends arranged along the first axis (A) and connected respectively to the first mounting seat 1 and the latch member 3 for biasing the latch member 3 away from the first mounting seat 1 toward the locking position. In this embodiment, the first resilient member 6 is configured as a compression spring.

The second resilient member 7 has opposite ends arranged along the first axis (A) and connected respectively to the second mounting seat 2 and the operating member 5 for biasing the operating member 5 away from the latch member 3 to return to its initial position when the button portion 51 of the operating member 5 is released. In this embodiment, the second resilientmember7isconfiguredasacompressionspring.

The retention unit 4 includes a plurality of barb-shapedfirsthooks4landapluralityofbarb-shaped second hooks 42. The second hooks 42 are connected fixedly to an outer surrounding surface of the first shaft segment 13 of the first mounting seat 1. Each of the first hooks 41 extends from the periphery of the button portion 51 of the operating member 5 through a respective one of the communication holes 2b in the direction of the first axis (A) The first hooks 41 correspond respectively in angular position to the secondhooks 42 when the secondmounting seat 2 is at the unfolded position, and are spaced apart from the second hooks 42 along the first axis (A) when the latch member 3 is at the locking position. When the button portion 51 of the operating member 5 is pressed to move toward the first mounting seat 1 to drive the movement of the latch member 3 from the locking position to the unlocking position, the button portion 51 simultaneously drives the first hooks 41 to move toward the first mounting seat 1 to engage respectively the second hooks 42, such that the operating member 5 and the first hooks 41 are prevented from moving away from the first mounting seat 1 through the engagement between the first andsecondhooks 41, 42toholdthelatchmember 3 at the unlocking position to permit the rotation of the secondmounting seat 2 relative to the first mounting seat 1 when the second mounting seat 2 is at the unfolded position and when the operating member 5 is released.

The latch member 3 is further formed with a plurality of through grooves 3a that are in spatial communication with the through hole 3b for receiving respectively the second hooks 42 when the latchmember 3 is at the unlocking position.

When the second mounting seat 2 rotates relative to the first mounting seat 1 to leave the unfolded position, each of the first hooks 41 is misaligned from the respective one of the second hooks 42 in the direction of the first axis (A) tobedisengagedfromthe respective one of the second hooks 42 to release the latch member 3. At this time, the latch member 3 is biased by the first resilient member 6 to abut against the second mounting seat 2 and is prevented from moving to the locking position due to the misalignment between the first and second locking grooves 11, 21, and the operating member 5 is biased to move away from the first mounting seat 1 to its initial positions by the second resilient member 7 to separate the first hooks 41 from the second hooks 42 along the first axis (A) , such that when the second mounting seat 2 rotates back to the unfolded position, the first hooks 41 cannot engage the second hooks 42 to hold the latch member 3 at the unlocking position, and the latch member 3 is biased by the first resilient member 6 to the locking position.

To sum up, by virtue of the retention unit 4, the latch member 3 can be moved from the locking position to the unlocking position, and be retained at the unlocking position to permit the rotation of the second mounting seat 2 relative to the first mounting seat 1 through a single depression operation of the operating memberS when the second mounting seat is at the unfolded position. Referring back to Figs. 1 and 2, in this invention, during a fold operation of the handle lb relative to the basket la, the operating member 5 of one of the joint devices 100 is depressed to drive the latch member 3 of the one of the joint device 100 to be held at the unlocking position, and the operating member 5 of the other one of the joint devices 100 is subseguently depressed to drive the latch member 3 of the other one of the joint device 100 to be held at the unlocking position. Then, the handle lb can be rotated relative to the basket la to the folded position. The abovementioned fold operation can be achieved by only one hand of a user, and is more convenient than that of the conventional baby basket.

Referring to Figs. 10 to 15, a second preferred embodiment of the joint device 100 according to the present invention is similar to the first preferred embodiment. What is different is that the retention unit 1 3 4' of the second preferred embodiment includes a locking groove 42' , a locking block 41' and a third resilient member 43' The locking groove 42' is formed in one of the latch portions 32 of the latch member 3.

The locking block 41' is mounted to the second mounting seat 2, and is movable relative to the second mounting seat 2 along a second axis (B) (see Fig. 12) of the second mounting seat 2 that is oblique to the first axis (A) The third resilient member 43' has opposite ends arranged along the second axis (B) and connected respectively to the locking block 41' and the second mounting seat 2 forbiasingthelockingblock4l' toward the latch member 3. In this embodiment, the third resilient member 43' is configured as a compression spring.

The locking groove 42' is aligned with the second axis (B) whenthesecondmountingseat2isattheunfolded position and when the latch member 3 is at the unlocking position (see Fig. 13) , such that the locking block 41' is biased by the third resilient member 43' to engage the locking groove 42' to hold the latch member 3 at the unlocking position in response to the movement of the latch member 3 from the locking position to the unlocking position driven by the operating member 5 to permit the rotation of the second mounting seat 2 relative to the first mounting seat 1.

The first mounting seat 1 is further formed with a first groove ic that is registered with the locking groove 42' when the latch member 3 is at the unlocking position. The second mounting seat 2 is further formed with a second groove 2c for extension of the locking block 41' therethrough.

The first mounting seat 1 has a groove defining surface that defines the first groove ic. The locking block 41' has an inclined surface 413' for contacting slidably the groove defining surface of the first mounting seat 1, so that the locking block 41' is pushed by the groove defining surface to be smoothly disengaged from the locking groove 42' to release the latch member 3 when the second mounting seat 2 leaves the unfolded position.

The looking block 41' further has an abutment surface 412' for contacting the groove defining surface when the second mounting seat 2 is at the unfolded position, so as to limit the rotation angle of the second mounting seat 2 relative to the first mounting seat 1.

Referring to Fig. 13, it is noted that there is a gap (G) between the latch member 3 and an interior end surface 25 of the second mounting seat 2 when the latch member3isattheunlockingpositionandwhenthesecond mounting seat 2 is at the uufoldedposition. Therefore, when the second mounting seat 2 leaves the unfolded position, the latchmember3is releasedbythe retention unit 4' and is biased by the first resilient member 6 to move to an intermediate position, where the latch member 3 abuts against the interior emd surface 25 of the secomd moumtimg seat 2 and is prevented from moving to the locking position due to the misalignment between the first and second locking grooves 11, 21, and where the locking groove 42' is rot registered with the first groove lc (i.e., the locking groove 42' is misaligned from the second axis (B) when the second mounting seat 2 is at the unfolded position) , such that the locking block 41' cannot engage the locking groove 42' to hold the latch member 3 at the unlocking position and the latch member 3 is biased back to the locking position by the first resilient member 6 when the second mounting seat 2 rotates back to the unfolded position.

Referring to Figs. 16 to 18, a third preferred embodiment of the joint device 100 according to the present invention is similar to the second preferred embodiment. The retention unit 4" of the third preferred embodiment also includes alockinggroove 42", alocking block 41" and a third resilient member 43". what is different is that the locking block 41" of the retention unit 4" is formed with a retaining groove 41a" that extends along the second axis B. The second mounting seat 2 further has a protrusion 2d that is retained in the retaining groove 41a". The third resilient member 43" is retained in the retaining groove 41a", and has opposite ends connected respectively to the locking block 41" and the protrusion 2d for biasing the locking block 41" toward the latch member 3.

Referring to Fig. 18, like the second preferred embodiment, there is a gap (G) between the latch member 3 and the interior end surface 25 of the second mounting seat 2 when the latch member 3 is at the unlocking position and when the second mounting seat 2 is at the unfolded position. Therefore, when the second mounting seat 2 leaves the unfolded position, the latch member 3 is biased by the first resilient member 6 to move to an intermediate position, where the latch member 3 abuts against the interior end surface 25 of the second mounting seat 2, such that the locking block 41" cannot engage the locking groove 42" to hold the latch member 3 at the unlocking position when the second mounting seat 2 rotates back to the unfolded position.

It is noted that, in the second and third preferred embodiments of this invention, the operating member 5 maybeconfigurednot tobeco-rotatablewithths second mounting seat 2 (i.e., the operating member 5 may not rotate about the first axis (A) when the second mounting seat 2 rotates relative to the first mounting seat 1)

Claims

Claims: 1. A joint device comprising: a first mounting seat formed with at least one first locking groove; a second mounting seat connected to said first mounting seat, formed with at least one second locking groove, and rotatable relative to said first mounting seataboutafirstaxis, saidsecondlockinggroovebeing aligned with said first locking groove in a direction of the first axis when said second mounting seat is at an unfolded position relative to said first mounting seat, said second locking groove being misaligned from said first locking groove when said secondmounting seat leaves the unfolded position; a latch member having at least one latch portion, and movable along the first axis between said first and second mounting seats, said latch portion of said latch member engaging said first locking groove and saidsecond locking groove to prevent the rotation of said second mounting seat relative to said first mounting seat when said latch member is at a Locking position, said latch portion of said latch member engaging said first locking groove and being disengaged from said second locking groove to permit the rotation of said second mounting seatrelativetosaidfirstmountingseatwhensaidlatch member is at an unlocking position; an operating member coupled to said latch member, and capable of being driven to move along the first axis toward said first mounting seat to drive movement of said latch member from the locking position to the unlocking position so that said second mounting seat can leave the unfolded position; and a retention unit configured to hold said latch member at the unlocking position in response to the movement of said latch member driven by said operating member from the locking position to the unlocking position to permittherotationofsaidsecondmountingseatrelative to said first mounting seat when said second mounting seat is at the unfolded position.
2. The joint device as claimed in claim 1, wherein said second mounting seat is configured to prevent said latch member from moving to the locking position due to the misalignment between said first and second locking grooves to permit the rotation of said second mounting seat relative to said first mounting seat when said second mounting seat leaves the unfolded position.
3. The joint device as claimed in claim 1, wherein said retentionunit is configuredto release said latchmember when said second mounting seat leaves the unfolded position.
4. The joint device as claimed in claim 1, wherein said 1 9 retention unit is configured so as not to hold said latch member at the unlocking position when said second mounting seat rotates back to the unfolded position.
5. The joint device as claimed in claim 1, wherein said latch member further has a circular body centered at the first axis, said latch portion of said latch member being disposed on a periphery of said circular body.
6. The joint device as claimed in claim 1, wherein said first mounting seat is formed with two said first locking grooves that are opposite to each other in a direction perpendicular to the first axis, said second mounting seat being formed with two said second locking grooves that are opposite to each other in a direction perpendiculartothefirstaxis, saidlatchmemberhaving two said latch portions that are opposite to each other in a direction perpendicular to the first axis.
7. The joint device as claimed in claim 1, wherein said first mounting seat is further formed with at least one first auxiliary locking groove, said second mounting seat being further formed with at least one second auxiliary locking groove corresponding to said first auxiliary locking groove, said latch member further having at least one auxiliary latch portion corresponding to said first auxiliary locking groove and said second auxiliary locking groove, said first auxiliary locking groove and second auxiliary locking groove having a dimension smaller than that of said latch portion of said latch member to prevent said latch portion from being engaged therewith when said second mounting seat leaves the unfolded position.
8. The joint device as claimed in claim 7, wherein said latch member further has a circular body centered at the first axis, said auxiliary latch portion of said latch member being disposed on a periphery of said circular body.
9. The joint device as claimed in claim 7, wherein said first mounting seat is formed with a plurality of said first auxiliary locking grooves, said second mounting seat being formed with a plurality of said second auxiliary locking grooves, said latch member having a plurality of said auxiliary latch portions.
10. The joint device as claimed in claim 1, wherein said first mounting seat further has a first shaft segment that extends along the first axis, said second mounting seat further having a second shaft segment that extends along the first axis, said latch member being formed with a through hole for extension of said first and second shaft segments.
11. The joint device as claimed in claim 1, further comprising a first resilient member that is connected to said latch member for biasing said latch member away from said first mounting seat toward the locking position -
12. The joint device as claimed in claim U, wherein said first resilient member has opposite ends arranged along the first axis and connected respectively to said first mounting seat and said latch member.
13. The joint device as claimed in claim U, wherein said first resilient member is configured as a compression spring.
14. The joint device as claimed in claim 1, further comprising a second resilient member that is connected to said operating member for biasing said operating member away from said latch member to return to its initial position.
15. The joint device as claimed in claim 14, wherein said second resilientmember has opposite ends arranged along the first axis and connected respectively to said second mounting seat and said operating member.
16. The joint device as claimed in claim 14, wherein said second resilient member is configured as a compression spring.
17. The joint device as claimed in claim 1, wherein: said second mounting seat is further formed with an extension hole; and said operating member has a button portion disposed at one side of said second mounting seat opposite to said latch member, and a rod portion extending from said button portion and through said extension hole in the direction of the first axis, said button portion being capable of being pressed to move toward said first mounting seat to drive said rod portion to push said latch member, and to drive the movement of said latch member from the locking position to the unlocking position when said second mounting seat is at the unfolded position.
18. The joint device as claimed in claim 17, further comprising a second resilient member that is connected to said button portion of said operating member for biasing saidoperatingmember away fromsaid latchmember to return to its initial position.
19. The joint device as claimed in claim 1, wherein said first mounting seat further has a first mounting segment 2 3 adaptedtobemountedwithabasket, said secondmounting seat further having a second mounting segment adapted to be mounted with a handle, a distal portion of the handle being distal from the basket when said second mounting seat is at the unfolded position, the distal portion of the handle being close to the basket when said second mounting seat is at a folded position.
20. The joint device as claimed in claim 1, wherein said retention unit includes a first hook connected fixedly to said operating member, and a secondhook connected fixedlyto said firstmounting seat, said first hook corresponding to said secoridhook, said operating member being capable of being driven to move toward said first mounting seat to drive the movementof saidlatchmember fromthe lockingposition to the unlocking position, and to drive said first hook to engage said second hook when said second mounting seat is at the unfolded position, so as to hold said latch member at the unlocking position.
21. The joint device as claimed in claim 20, further comprising a second resilient member that is connected to said operating member for biasing said operating member away from said first mounting seat to return to its initial position.
22. The joint device as claimed in claim 20, wherein said first hook being misaligned from said second hook in the direction of the first axis to be disengaged from said second hook to release said latch member when said second mounting seat leaves the unfolded position.
23. The joint device as claimed in claim 20, further comprising a second resilient member that is connected to said operating member for biasing said operating member away from said first mounting seat to return to its initial position, said first hook being misaligned from said second hook in the direction of the first axis to be disengaged from said second hook to release said latch member when said second mounting seat leaves the unfolded position, said operating member being biased to move away from said first mounting seat by said second resilient member to separate said first hook from said second hook along the first axis when said first hook ismisalignedfromsaidsecondhook, suchthatsaidfirst hook cannot engage said second hook when said second mounting seat rotates back to the unfolded position.
24. The joint device as claimed in claim 20, wherein said first mounting seat further has a first shaft segment that extends along the first axis, said second hook being connected fixedly to said first shaft segment of said first mounting seat, said second mounting seat further having a second shaft segment that extends along the first axis, that is connected to and inserted into said first shaft segment, and that is rotatable relative to said first shaft segment about the first axis, said latch member being formed with a through hole for extension of said first and second shaft segments, and a through groove that is in spatial communication with said through hole for receiving said second hook.
25. The joint device as claimed in claim 20, wherein: said second mounting seat is further formed with an extension hole and a comnunication hole; and said operating member has a button portion disposed at one side of said secondmountingseatopposttetosaidlatchmember, said first hook extending from said button portion through said communication hole in the direction of the first axis, and a rod portion extending from said button portion and through said extension hole in the direction of the first axis, said button portion being capable of being driven to move toward said first mounting seat co drive said rod portion to push said latch member to drive the movement of said latch member from the locking position to the unlocking position, and to drive said first hook to engage said second hook to hold said latch member at the unlocking position when said secondmounting seat is at the unfolded position.
26. The joint device as claimed in claim 1, wherein said retention unit includes a locking groove formed in said latch member, and a locking blockmounted to said secondmounting seat and movable relative to said second mounting seat along a second axis of said secondmounting seat that is oblique to the first axis, said locking groove being aligned with said second axis when said second mounting seat is at the unfolded position and when said latch member is at the unlocking position, such that said locking block is able to be biased to engage said locking groove to hold said latch member at the unlocking position.
27. The joint device as claimed in claim 26, wherein said locking groove is formed in said latch portion of said latch member.
28. The joint device as claimed in claim 26, wherein said retention unit further includes a third resilient member connected to said locking block for biasing said locking block toward said latch member, such that said locking block is biased by said third resilient member to engage said locking groove to hold said latch member at the unlocking position in response to the movement of said latch member from the locking position to the unlocking position to permit the rotation of said second mounting seat relative to said first mounting seat when said second mounting seat is at the unfolded position and when said operating member is released.
29. The joint device as claimed in claim 28, wherein said third resilientmember has opposite ends connected respectively to said locking block and said second mounting seat.
30. The joint device as claimed in claim 28, wherein said third resilient member is configured as a compression spring.
31. The joint device as claimed in claim 26, wherein said lockingblock is disengaged from said locking groove to release said latch member through the misalignment between said locking groove and the second axis when saidsecondmountingseat leaves theunfoldedpcsition.
32. The joint device as claimed in claim 26, wherein, when said second mounting seat leaves the unfolded position, said latch member is configured to be moved to an intermediate position between the locking and unlocking positions, where said latch portion of said latch member is disengaged from said second locking groove to permit the rotation of said seoond mounting seat relative to said first mounting seat, such that said locking block cannot engage said locking groove to hold said latch member ar the unlocking position when said second mounting seat rotates back to the unfolded position -
33. The joint device as claimed in claim 26, wherein: said first mounting seat is formedwith a first groove that is registered with said locking groove when said latch member is at the unlocking position; said locking block has an inclined surface for contacting slidably a groove defining surface of said first mounting seat that defines said first groove, so thatsaidlockingblockispushedbysaidgroovedefining surface to be disengaged from said locking groove to release said latchmember when said secondmounting seat leaves the unfolded position.
34. The joint device as claimed in claim 33, wherein said second mounting seat is formed with a second groove for extension of said locking block therethrough.
35. The joint device as claimed in claim 33, wherein said locking block further has an abutment surface for contacting said groove defining surface when said second mounting seat is at the unfolded position, so as to limit 2 9 the rotation angle of said second mounting seat relative to said first mounting seat.
36. The joint device as claimed in claim 26, wherein said locking block is formed with a retaining groove that extends alongthe secondaxis, saidsecondmounting seat further having a protrusion that is retained in said retaining groove.
37. The joint device as claimed in claim 36, further comprising a third resilient member that is retained in said retaining groove and that has opposite ends connected respectively to said locking block and said protrusion for biasing said locking block toward said latch member.
38. A joint device substantially as herein described with reference to the accompanying figures.