Locking joint and child carrier

Abstract

This disclosure discloses a locking joint, comprising: a first connecting seat; a second connecting seat, the first connecting seat and the second connecting seat being pivotable about an axial direction and circumferentially relative to each other; and a locking member disposed between the first connecting seat and the second connecting seat along the axial direction and movable relative to both along the axial direction and engaging with both, wherein the first connecting seat has a limiting portion extending in a direction parallel to the axial direction, and the locking member has an engaging portion extending in a direction parallel to the axial direction. When the locking member engages with the second connecting seat, and the engaging portion engages with the limiting portion, the first connecting seat can pivot relative to the second connecting seat in the positive direction of the circumferential direction, but cannot pivot relative to the second connecting seat in the opposite direction of the circumferential direction. This disclosure also discloses a child carrier.

Description

Locking joints and child carriers The present disclosure relates to a locking joint and a children's carrier. Currently, child carriers, such as strollers, all feature a foldable function for easy portability. Most folding and locking mechanisms utilize hooks to prevent accidental unfolding of the folded frame. However, these hooks often require manual operation to release the lock, making single-handed unfolding difficult. Furthermore, the hooks can diminish the overall aesthetics of the frame. According to the present disclosure, a locking joint is proposed, including: a first connecting seat; a second connecting seat, the first connecting seat and the second connecting seat being able to pivot relative to each other axially and circumferentially; a locking member, which is axially arranged between the first connecting seat and the second connecting seat and can move axially relative to the two and engage with the two, wherein the first connecting seat is provided with a limiting portion extending in a direction parallel to the axial direction, and the locking member is provided with an engaging portion extending in a direction parallel to the axial direction, when the locking member is engaged with the second connecting seat, and the engaging portion is engaged with the limiting portion, the first connecting seat can pivot relative to the second connecting seat in a positive direction of the circumference, but cannot pivot relative to the second connecting seat in a negative direction of the circumference. In one embodiment, the inner circumference of the first connecting seat is provided with a plurality of first teeth arranged at intervals along the circumferential direction, the inner circumference of the second connecting seat is provided with a plurality of second teeth arranged at intervals along the circumferential direction, the outer circumference of the locking member is provided with a plurality of latching teeth arranged at intervals along the circumferential direction and capable of engaging with the first teeth and the second teeth, the limiting portion is provided on the end surface of the first teeth close to the second connecting seat in a direction parallel to the axial direction, the engaging portion is provided on the end surface of the latching teeth away from the second connecting seat in a direction parallel to the axial direction, the first connecting seat is further provided with a blocking surface, the blocking surface is located on one side of the limiting portion in the circumferential direction, and The locking member is further provided with a contact surface, which is located on one side of the engaging portion in the circumferential direction and is located on the same tooth as the engaging portion; when the locking member is engaged with the second connecting seat and the engaging portion is engaged with the limiting portion, the multiple engaging teeth are staggered and engaged with the multiple second teeth along the circumferential direction, and at least one engaging tooth is opposite to at least one first tooth in a direction parallel to the axial direction, the blocking surface and the contact surface are in contact with each other along the circumferential direction, and the contact surface is located on the opposite side of the blocking surface in the circumferential direction, so as to limit the limiting portion from pivoting in the opposite direction of the circumferential direction relative to the engaging portion. In one embodiment, the engaging portion protrudes from the end surface of the corresponding engaging tooth away from the second connecting seat toward the first connecting seat in a direction parallel to the axial direction, and the abutting surface is located on the surface of the engaging portion on the positive side of the circumferential direction. In one embodiment, the engaging portion is located on the opposite side of the corresponding engaging tooth in the circumferential direction and does not extend to the positive side of the corresponding engaging tooth in the circumferential direction; the limiting portion is recessed along a direction parallel to the axial direction from the end face of the corresponding first tooth close to the second connecting seat toward the side away from the second connecting seat, and the limiting portion is located on the opposite side of the corresponding first tooth in the circumferential direction and penetrates the corresponding first tooth in the opposite direction of the circumferential direction, and the blocking surface is located on the positive side of the limiting portion in the circumferential direction; when the limiting portion and the engaging portion are engaged, the engaging portion is at least partially embedded in the limiting element portion. In one embodiment, the blocking surface and the abutting surface are both parallel to the axial direction. In one embodiment, at least one of the first connecting seat and the locking member is provided with a guiding bevel, and the guiding bevel is used to guide the first tooth provided with the limiting portion to pass over the engaging portion along the positive direction of the circumference; the guiding bevel is provided on the surface of the first tooth provided with the limiting portion on the positive direction side of the circumference, and is inclined to the direction parallel to the axial direction and the circumference; and / or, the guiding bevel is provided on the surface of the engaging portion on the opposite direction side of the circumference, and is inclined to the direction parallel to the axial direction and the circumference. In one embodiment, the first connecting seat is further provided with a stop surface, which is located on one side of the blocking surface in the circumferential direction, and the stop surface and the blocking surface are located on the same first tooth; the locking member is further provided with a contact surface, which is located on one side of the abutment surface in the circumferential direction, and the abutment surface and the abutment surface are located on the same tooth; when the locking member is engaged with the second connecting seat, and the engaging portion is engaged with the limiting portion, the stop surface and the abutment surface abut against each other in a direction parallel to the axial direction. In one embodiment, the stop surface is located on the side of the blocking surface in the opposite direction of the circumferential direction and on the side of the limiting portion in the direction parallel to the axial direction, and the contact surface is located on the side of the abutment surface in the opposite direction of the circumferential direction and on the side of the locking portion in the direction parallel to the axial direction; or, the stop surface is located on the side of the blocking surface in the positive direction of the circumferential direction, and the contact surface is located on the side of the abutment surface in the positive direction of the circumferential direction. In one embodiment, the engaging portion is located at the radial outer end of the corresponding engaging tooth; the limiting portion protrudes from the end face of the corresponding first tooth close to the second connecting seat toward the second connecting seat in a direction parallel to the axial direction, and the limiting portion is located on the positive direction side of the corresponding first tooth in the circumferential direction, and does not extend to the opposite direction side of the corresponding first tooth in the circumferential direction, and the blocking surface is located on the surface of the limiting portion on the opposite direction side of the circumferential direction; when the limiting portion and the engaging portion are engaged, the engaging portion abuts against the limiting portion along the circumferential direction. In one embodiment, the blocking surface and the abutting surface are both inclined with respect to the radial direction and the circumferential direction. In one embodiment, at least one of the first connecting seat and the locking member is provided with a guiding bevel, which is used to guide the limiting portion to pass over the engaging portion along the positive direction of the circumference; the guiding bevel is provided on the surface of the limiting portion on the positive direction side of the circumference, and is inclined with respect to the radial and circumferential directions; and / or, the guiding bevel is provided on the surface of the engaging portion on the opposite direction side of the circumference, and is inclined with respect to the radial and circumferential directions. In one embodiment, the inclination angle of the abutment surface is greater than the inclination angle of the guiding inclined surface. In one embodiment, the locking member is provided with a recess, which is formed in a direction parallel to the axial direction from the end surface of the tooth provided with the engaging portion away from the second connecting seat toward the second connecting seat, and is formed radially between the engaging portion and the corresponding tooth. In one embodiment, the first connecting seat is further provided with a stop surface, which is located on the end surface of the first tooth provided with the limiting portion close to the second connecting seat in a direction parallel to the axial direction and is located on the side opposite to the blocking surface in the circumferential direction; the locking member is further provided with a contact surface, which is located on the end surface of the engaging portion away from the second connecting seat in a direction parallel to the axial direction; when the locking member is engaged with the second connecting seat and the engaging portion is engaged with the limiting portion, the stop surface and the contact surface contact each other in a direction parallel to the axial direction. In one embodiment, except for the first tooth with a limiting portion, each of the remaining first teeth has a groove, and the groove is formed along a direction parallel to the axial direction from the end surface of the corresponding first tooth close to the second connecting seat toward the side away from the second connecting seat. The groove passes through the corresponding first tooth along the circumferential direction, and the groove is used to accommodate the locking portion along a direction parallel to the axial direction. In one embodiment, the depth of the groove is greater than or equal to the length of the engaging portion. In one embodiment, the limiting portion is formed by protruding from the end face of the corresponding first tooth close to the second connecting seat toward the second connecting seat in a direction parallel to the axial direction, and the blocking surface is located on the surface of the limiting portion on the opposite side of the circumferential direction; the locking portion is formed by being recessed from the end face of the corresponding locking tooth away from the second connecting seat toward the second connecting seat, the abutting surface is located on the opposite side of the locking portion in the circumferential direction, and the locking portion penetrates the locking tooth in the positive direction of the circumference; except for the locking tooth with the locking portion, each of the remaining locking teeth has a groove, and the groove is recessed from the end face of the corresponding locking tooth away from the second connecting seat toward the second connecting seat in a direction parallel to the axial direction, and the groove penetrates the corresponding locking tooth along the circumferential direction, and the groove is used to accommodate the limiting portion in a direction parallel to the axial direction. In one embodiment, the first connecting seat is provided with two limiting portions, which are respectively provided on the two first teeth; the second connecting seat is provided with two engaging portions, which are respectively provided on the two engaging teeth. In one embodiment, the locking joint includes a driving member axially located between the first connecting seat and the locking member to drive the locking member to move toward the second connecting seat. In one embodiment, the locking joint includes an elastic member, which is axially located between the second connecting seat and the locking member to drive the locking member to move toward the first connecting seat. According to the present disclosure, a child carrier is proposed, which includes: a frame; and a locking joint according to the present disclosure, wherein the frame includes a push handle and a linkage rod pivotally connected to the push handle through the locking joint, the push handle is connected to the first connecting seat, and the linkage rod is connected to the second connecting seat, the push handle pivots toward the linkage rod along the positive direction of the circumference to achieve the folding of the push handle and the linkage rod, and the push handle pivots away from the linkage rod along the negative direction of the circumference to achieve the expansion of the push handle and the linkage rod. According to the present disclosure, a child carrier is proposed, which includes: a frame; and a locking joint according to the present disclosure, wherein the frame includes a push handle and a linkage rod pivotally connected to the push handle through the locking joint, the push handle is connected to the first connecting seat, and the linkage rod is connected to the second connecting seat, the push handle pivots toward the linkage rod along the positive direction of the circumference to achieve the retraction between the push handle and the linkage rod, and the push handle pivots away from the linkage rod along the negative direction of the circumference to achieve the expansion between the push handle and the linkage rod; the push handle has an operating member connected to the driving member, and the operating member is operated to drive the locking member to move toward the second connecting seat, so that the locking member engages with the second connecting seat and the first connecting seat can pivot relative to the second connecting seat. While the invention has been illustrated and described herein with reference to particular embodiments, the invention should not be limited to the details shown, rather various modifications may be made to the details within the scope of the claims and range of equivalents without departing from the invention. The descriptions of directions such as "front", "back", "up" and "down" involved in this article are only for the convenience of understanding. The present invention is not limited to these directions, but can be adjusted according to actual conditions. Although the present application has been described with reference to typical embodiments, the terms used are illustrative and exemplary, rather than restrictive. Figure 1 is a side view of a child carrier 1 according to the present disclosure in its deployed state. The child carrier 1, for example, a stroller, comprises a frame. The frame includes a handlebar 10, a linkage rod 20, a rider 30, a front leg assembly 40, a rear leg assembly 50, a seat assembly 60, and armrests 70. The front leg assembly 40, the rear leg assembly 50, and the rider 30 are pivotally connected to each other at a frame joint 200. The rider 30 is pivotally connected to the handlebar 10, which is pivotally connected to the linkage rod 20 via a locking joint 100. The other end of the linkage rod 20 is pivotally connected to the rear leg assembly 50. The locking joint 100 has a first locking state, a second locking state, and an unlocking state. When the locking joint 100 is in the first locking state, the push handle 10 cannot pivot relative to the linkage rod 20, and the two are in a locked state. When the locking joint 100 is in the second locking state, the push handle 10 can only pivot relative to the linkage rod 20 in the positive direction of the pivot direction, and cannot rotate relative to the linkage rod 20 in the opposite direction of the pivot direction. When the locking joint 100 is in the unlocking state, the push handle 10 can pivot relative to the linkage rod 20 in both the positive and negative directions of the pivot direction. According to the present disclosure, when the frame is in the expanded state, the locking joint 100 is in the first locking state, so that the push handle 10 and the linkage rod 20 are relatively fixed to prevent accidental folding. At this time, a child can sit on the frame, and the user can push the frame. As shown in the subsequent FIG3 , when the frame is in the collapsed and locked state, the locking joint 100 is in the second locked state, allowing the push handle 10 to pivot relative to the linkage rod 20 only in a direction toward the linkage rod 20 (corresponding to the positive pivot direction, i.e., the collapsed direction D1), but not in a direction away from the linkage rod 20 (corresponding to the opposite pivot direction, i.e., the deployed direction D2). When the frame is switched from the deployed state to the collapsed state, the locking joint 100 is in the unlocked state, allowing the push handle 10 to pivot relative to the linkage rod 20 both toward the linkage rod 20 and away from the linkage rod 20. FIG2 is a front perspective view of the frame of the child carrier 1 according to the present disclosure, shown in its unfolded state. FIG2 clearly illustrates the connection between the handle 10, linkage rod 20, rider 30, front leg element 40, rear leg element 50, seat element 60, and armrest 70. The handle 10 is provided with an operating member 11, for example, disposed on the top horizontal bar of the handle 10, such as a button. The operating member 11 is connected to the locking joint 100 and is used to release the locking joint 100 from its first locked state and switch the locking joint 100 from the first locked state to an unlocked state. For example, the operating member 11 is connected to the locking joint 100 via a traction member (e.g., a rope, cable, etc.) extending within the handle 10. The traction member allows movement of the operating member 11, thereby moving some components of the locking joint 100 and switching the state of the locking joint 100. According to this embodiment, when the operating member 11 is operated, for example, when the operating member 11 is pressed, the locking joint 100b can be switched from the first locking state to the unlocking state, so that the push handle 10 can be pivoted relative to the linkage rod 20 in the direction close to the linkage rod 20, that is, the push handle 10 of the frame that was originally in the unfolded state can be pivoted toward the side close to the linkage rod 20 to fold the push handle 10 toward the linkage rod 20. Specifically, as shown in Figure 2, the push handle 10 can be pushed toward the linkage rod 20 and rotated counterclockwise around the locking joint 100 relative to the linkage rod 20, thereby driving the linkage rod 20, the rider 30, the front foot element 40, and the rear foot element 50 to fold relative to each other. The folded and locked state after folding is shown in Figure 3. At this time, the user can use the armrest 70 to lift the entire child carrier 1 for easy carrying or storage. 2 to the folded and locked state of FIG. 3 , the push handle 10 can pivot relative to the linkage rod 20 in a direction close to the linkage rod 20 or in a direction away from the linkage rod 20 . Figure 4 is a decomposition diagram of a locking joint 100 according to an embodiment. According to this embodiment, the locking joint 100 has a first connecting seat 110, a second connecting seat 120, a locking member 130, a driving member 140 and an elastic member 150 arranged along the axial direction I. The first connecting seat 110 is fixedly connected to the push handle 10, the second connecting seat 120 is fixedly connected to the linkage rod 20, and the driving member 140, the locking member 130 and the elastic member 150 are sequentially accommodated between the first connecting seat 110 and the second connecting seat 120. The first connecting seat 110 can pivot relative to the second connecting seat 120 along the circumferential direction C around the axial direction I. It can be seen that the circumferential direction C is arranged around the axial direction I, wherein the circumferential direction C corresponds to the pivot direction, and the positive direction of the circumferential direction C corresponds to the folding direction D1, and the negative direction of the circumferential direction C corresponds to the unfolding direction D2. FIG7 is an inverted perspective view of the locking member 130 in FIG4 . As shown in FIG4 and FIG7 , the locking member 130 resembles a ring-shaped gear, having a plurality of teeth evenly spaced along the circumferential direction C on its outer periphery. The plurality of teeth include a plurality of meshing teeth 131, and two locking teeth 132 and 134 disposed between and spaced from two adjacent meshing teeth 131. The locking member 130 further has a circular through-hole 133 extending through the locking member 130 along the axial direction I. The two locking teeth 132 and 134 are radially spaced apart, i.e., the centers of the two locking teeth 132 and 134 are 180° apart from each other, and the two locking teeth 132 and 134 have different shapes. According to the present disclosure, only one locking tooth 132 or 134 may be provided, or the two locking teeth 132, 134 may not be arranged radially opposite to each other, that is, the centers of the two locking teeth 132, 134 are not arranged 180 degrees relative to each other, but are arranged at an angle between 0° and 180°. The present disclosure is not limited to this. It can be seen that the radial direction is perpendicular to the axial direction I and the circumferential direction C. The elastic member 150 (eg, a compression spring in a spring, described below as the spring 150 ) is located between the second connecting seat 120 and the locking member 130 to apply a driving force to cause the locking member 130 to enter the first connecting seat 110 . The driving member 140 has an elongated through-hole 141 and a driving portion 142. Its upper end is connected to the operating member 11 via, for example, a traction member extending through the push handle 10. The elongated through-hole 141 extends through the driving member along the axial direction I and extends radially. The driving portions 142 are disposed on opposite sides of the elongated through-hole 141 and extend parallel to the radial direction and the axial direction I. They are sloped to facilitate sliding engagement with the sloped driving portion 113 (see below and FIG. 5 ) in the first connecting seat 110. The second connecting seat 120 is provided with a circular accommodating portion, and has a locking portion 122 and a locking portion 123 arranged at intervals along the radial direction on its inner circumference, and a plurality of second teeth 121 evenly spaced along the circumferential direction C between the locking portion 122 and the locking portion 123. When the locking member 130 enters the circular accommodating portion of the second connecting seat 120, the engaging teeth 131 of the locking member 130 will be staggered with the second teeth 121 of the second connecting seat 120 along the circumferential direction C, and the locking teeth 132 and 134 of the locking member 130 will be accommodated in the locking portions 122 and 123 one by one in a direction parallel to the axial direction I. At this time, the locking member 130 cannot rotate relative to the second connecting seat 120 along the circumferential direction C. Because the locking teeth 132 and 134 have different shapes, the locking portion 122 and the locking portion 123 also have different shapes accordingly. This prevents the locking teeth 132 from being stuck in an unmatched locking portion 123, and the locking teeth 134 from being stuck in an unmatched locking portion 122. Consequently, the locking member 130 can only enter the circular receiving portion of the second connecting seat 120 at a specific position. The bottom of the second connecting seat 120 is used to support the spring 150 in a direction parallel to the axial direction I. FIG5 is an exploded view of a locking joint 100 according to an embodiment. FIG5 is viewed from the opposite perspective to FIG4 , so that the internal structure of the first connecting seat 110 can be seen. FIG6 is a three-dimensional view of the first connecting seat 110 of FIG5 . The first connecting seat 110 is also provided with a circular accommodating portion corresponding to the second connecting seat 120, and its inner circumference also has a locking portion 114 and a locking portion 115 arranged at intervals along the radial direction, and a plurality of first teeth 111 uniformly arranged at intervals along the circumferential direction C between the locking portion 114 and the locking portion 115. The number and arrangement of the first teeth 111 correspond to the plurality of second teeth 121 of the second connecting seat 120, and the relative positional relationship between the locking portions 114, 115 and the plurality of first teeth 111 corresponds to the relative positional relationship between the locking portions 122, 123 and the plurality of second teeth 121. Similarly, when the locking member 130 enters the circular receiving portion of the first connecting seat 110, the engaging teeth 131 of the locking member 130 are staggered with the first teeth 111 of the first connecting seat 110 along the circumferential direction C, and the locking teeth 132 and 134 of the locking member 130 move in a direction parallel to the axial direction I and are received in the two locking portions 115 and 114 in a one-to-one correspondence (see FIG. 5 ). At this time, the locking member 130 cannot rotate relative to the first connecting seat 110 in the circumferential direction C. Similarly, the locking portions 114 and 115 also have correspondingly different shapes so as to receive the locking teeth 134 and 132 in a one-to-one correspondence in a direction parallel to the axial direction I, thereby ensuring that the locking member 130 can enter the circular receiving portion of the first connecting seat 110 only at a specific position. A pin 112 is provided at the center of the bottom of the first connecting seat 110, extending toward the second connecting seat 120 in a direction parallel to the axial direction I. The other end of the pin 112 extends to the second connecting seat 120 when the first and second connecting seats 110, 120 are assembled. The circular through-hole 133 of the locking member 130 is shaped and sized to match the pin 112, allowing the locking member 130 to rotate about the pin 112. The bottom of the first connecting seat 110 is also provided with a sloped driving portion 113. The shape of this driving portion 113 corresponds to the sloped driving portion 142 of the driving member 140. Both the driving portion 113 of the first connecting seat 110 and the driving portion 142 of the driving member 140 are provided with inclined surfaces that abut against each other in a direction parallel to the axial direction I. Both inclined surfaces are inclined in both the direction parallel to the axial direction I and the radial direction and are parallel to each other. In addition, the pin 112 passes through the elongated through-hole 141 of the driving member 140 in a direction parallel to the axial direction I. The elongated through-hole 141 is radially wider than the pin 112, allowing the driving member 140 to move radially relative to the pin 112 through the elongated through-hole 141. For example, when the operating member 11 pulls the driving member 140 radially (as shown in Figures 4 and 5, upward) through the traction member, since the inclined surface of the sloped driving portion 113 is inclined parallel to the radial direction and the axial direction I, the driving member 140 moves radially while driving the locking member 130 adjacent to it along the axial direction I to also translate along the axial direction I toward the side away from the first connecting seat 110, and compress the spring 150. According to this embodiment, the first connection base 110 includes two limiting portions 116 . The two limiting portions 116 (e.g., notches 116 , described below as notches 116 ) are disposed one-to-one on two first teeth 111 spaced apart along the circumferential direction C. The two first teeth 111 are spaced approximately 180° apart. Alternatively, the first connection base 110 may include only one limiting portion 116 disposed on one first tooth 111. The notch 116 is recessed along a direction parallel to the axial direction I from the end surface of the corresponding first tooth 111 close to the second connecting seat 120 toward a side away from the second connecting seat 120, and is arranged on the side of the corresponding first tooth 111 in the opposite direction of the circumferential direction C, that is, the side of the expansion direction D2, and penetrates the first tooth 111 in the opposite direction D2 of the circumferential direction C, but does not penetrate the first tooth 111 in the positive direction D1 of the circumferential direction C, that is, the notch 116 does not penetrate the entire corresponding first tooth 111 along the circumferential direction C, thereby forming a blocking surface 118 located on the side of the notch 116 in the positive direction D1 of the circumferential direction C and a stopping surface 119 located on the side of the notch 116 in a direction parallel to the axial direction I on the first connecting seat 110. Specifically, the blocking surface 118 extends in a direction parallel to the axial direction I, and the stopping surface 119 extends in a direction intersecting with the axial direction I. For example, the stopping surface 119 is parallel to the direction perpendicular to the axial direction I, that is, the blocking surface 118 and the stopping surface 119 are perpendicular to each other. With the exception of the first tooth 111 having the notch 116 , a groove 117 is formed on the remaining first teeth 111, extending from the end surface of each first tooth 111 closest to the second connecting seat 120 parallel to the axial direction I toward a side away from the second connecting seat 120 . The groove 117 extends through the entire corresponding first tooth 111 along the circumferential direction C but does not extend through the entire corresponding first tooth 111 radially. That is, the bottom of the groove 117 is not located at the end surface of the first tooth 111 closest to the second connecting seat 120 parallel to the axial direction I. Furthermore, the depth of the groove 117 is equal to or greater than the extended length of the protrusion 135 (described below). The angle of the locking member 130 shown in FIG7 is the inverted opposite of the angle of the first connecting seat 110 shown in FIG6 . According to this embodiment, the locking member 130 further includes two engaging portions 135 . These engaging portions 135 are configured to be received in the two recesses 116 of the first connecting seat 110 when the locking joint 100 is in the second locked state. The two engaging portions 135 (e.g., protrusions 135 , described below as protrusions 135 ) are disposed in a one-to-one correspondence on two engaging teeth 131 spaced apart along the circumferential direction C. The two engaging teeth 131 are spaced approximately 180° apart. Alternatively, the locking member 130 may include only one engaging portion 135 on one engaging tooth 131 . Specifically, the protrusion 135 protrudes from the end surface of the corresponding engaging tooth 131 away from the second connecting seat 120 toward the first connecting seat 110 in a direction parallel to the axial direction I, and is provided on the side of the corresponding engaging tooth 131 in the opposite direction D2 of the circumferential direction C, but is not provided on the side of the corresponding engaging tooth 131 in the positive direction D1 of the circumferential direction C, that is, the protrusion 135 is not continuously provided along the circumferential direction C on the entire end surface of the corresponding engaging tooth 131 away from the second connecting seat 120 in a direction parallel to the axial direction I. In other words, the cross section of the protrusion 135 is smaller than the cross section of the corresponding engaging tooth 131. The locking member 130 further includes an inclined guide surface 138, an abutting surface 139, and an abutting surface 160. The inclined guide surface 138, the abutting surface 139, and the abutting surface 160 are all formed on the surface of the projection 135. Specifically, the inclined guide surface 138 is formed on the surface of the projection 135 on the side opposite to the circumferential direction C in the direction D2 and is inclined with respect to a direction parallel to the axial direction I and the circumferential direction C. The abutting surface 139 is formed on the surface of the projection 135 on the side opposite to the circumferential direction C in the direction D1 and extends in a direction parallel to the axial direction I. The abutting surface 160 is formed on the end surface of the projection 135 in a direction parallel to the axial direction I. Specifically, the inclined guide surface 138 is an arcuate surface inclined with respect to a direction parallel to the axial direction I and the circumferential direction C, the abutting surface 139 is parallel to the axial direction I, and the abutting surface 160 extends in a direction perpendicular to the axial direction I. The inclined guide surface 138, the abutting surface 160, and the abutting surface 139 are sequentially connected to each other. The guiding slope 138 is used to guide the first tooth 111 with the notch 116 to slide along the positive direction D1 of the circumferential direction C to the end surface of the protrusion 135 parallel to the axial direction I. The abutment surface 139 is used to abut against the blocking surface 118 along the positive direction D1 of the circumferential direction C to prevent the first tooth 111 with the notch 116 from passing over the protrusion 135 along the reverse direction D2 of the circumferential direction C. The abutment surface 160 is used to abut against the abutment surface 119 along a direction parallel to the axial direction I to limit the depth of the protrusion 135 extending into the first connecting seat 130, thereby limiting the depth of the locking member 130 extending into the first connecting seat 110. According to the present disclosure, the protrusion 135 may also be provided on the locking teeth 132 and 134.According to the present disclosure, the guide bevel 138 can also be set on the surface of the first tooth 111 provided with the recess 116, rather than on the surface of the protrusion 135. Specifically, it is set on the side of the first tooth 111 along the positive direction D1 of the circumferential direction C to guide the first tooth 111 to slide along the positive direction D1 of the circumferential direction C to the end face of the protrusion 135 in the direction parallel to the axial direction I. Alternatively, the surface of the first tooth 111 provided with the recess 116 and the surface of the protrusion 135 can both be provided with the guide bevel 138. The operation of the locking joint 100 according to the present disclosure is described with reference to Figures 8 to 11. Figure 8 is a cross-sectional view of the locking joint 100 according to one embodiment when the vehicle frame is in an expanded state. Figure 10 is a cross-sectional view of the locking joint 100 according to one embodiment when the vehicle frame is in a collapsed locked state. In Figure 8 , the locking joint 100 is in the first locked state, corresponding to the state shown in Figures 1 and 2 . The handlebar 10 and linkage rod 20 are substantially aligned, and the frame is locked in the extended state. At this point, the locking teeth 132 and 134 of the locking member 130 are simultaneously received in the locking portions 115 and 114 of the first connecting seat 110 (see Figure 6 ) and the locking portions 122 and 123 of the second connecting seat 120 (see Figure 4 ), parallel to the axial direction I. In addition, the engaging teeth 131 (see Figure 7) of the locking member 130 are also arranged in an interlaced manner with the first teeth 111 (see Figure 6) and the second teeth 121 (see Figure 4) along the circumferential direction C, that is, the engaging teeth 131, the locking teeth 132, and the locking teeth 134 are engaged with the first teeth 111 and the second teeth 121 along the circumferential direction C at the same time. The first teeth 111 and the second teeth 121 are arranged relative to each other in a direction parallel to the axial direction I, so that the push handle 10 and the linkage rod 20 cannot pivot relative to the locking member 130, that is, the push handle 10 and the linkage rod 20 cannot pivot relative to each other, thereby preventing the push handle 10 from accidentally retracting relative to the linkage rod 20 when the frame is in the unfolded state. In addition, the protrusion 135 provided on the meshing tooth 131 is also located between the two first teeth 111 along the circumferential direction C, and the recess 116 is provided on the first tooth 111. It can be seen that the protrusion 135 and the recess 116 are arranged along the circumferential direction C, and the protrusion 135 is arranged farther away from the second connecting seat 120 along the direction parallel to the axial direction I than the recess 116. In this situation, the driving member 140 is not operated, and the pin 112 of the first connecting seat 110 abuts against one end (the upper end in FIG8 ) of the elongated through-hole 141 of the driving member 140. The spring 150 located between the second connecting seat 120 and the locking member 130 applies a pushing force to the locking member 130 in the spring receiving portion 136 of the locking member 130, causing the other side of the locking member 130 to abut against the driving member 140, and the driving member 140 to abut against the first connecting seat 110. The locking joint 100 in FIG10 is in the second locking state, which corresponds to the state in FIG3 , where the push handle 10 and the linkage rod 20 are folded, and the frame is in the folded and locked state. To achieve this state, the user can press the operating member 111 shown in FIG2 to remotely operate the driving member 140 (as shown in FIG8 , for example, by pulling the driving member 140 upwards), and the driving member 140 thereby applies a thrust to the locking member 130 toward the second connecting seat 120 and compresses the spring 150, causing the locking member 130 to move away from the first connecting seat 110 in the axial direction I, so that the meshing teeth 131, the locking teeth 132, and the locking teeth 134 of the locking member 130 only engage with the second teeth 121 of the second connecting seat 120 in the circumferential direction C. The locking teeth 132 and 134 of the locking member 130 are interlaced and disengaged from the first teeth 111 of the first connecting seat 110, so that they are only received in the locking portions 122 and 123 of the second connecting seat 120 and disengaged from the locking portions 115 and 114 of the first connecting seat 110 in a direction parallel to the axial direction I. However, the two protrusions 135 are still received in the first connecting seat 110. At this time, the locking member 130 still does not rotate relative to the second connecting seat 120, that is, the locking member 130 and the second connecting seat 120 are relatively fixed. As a result, the first connecting seat 110 can rotate relative to the linkage rod 20 provided with the second connecting seat 120 and the locking member 130 as the push handle 10 is pushed in the retracting direction D1, allowing the push handle 10 and the linkage rod 20 to be retracted. After the push handle 10 starts to rotate along the folding direction D1, the locking joint 100 is in the unlocked state, and the user can release the operating member 11. In this case, due to the relative rotation of the first connecting seat 110 and the second connecting seat 120, the locking teeth 132, 134 will no longer be opposite to the locking parts 115, 114 in the direction parallel to the axial direction I, but will be offset from each other along the circumferential direction C, that is, the locking teeth 132, 134 cannot be accommodated in the locking parts 115, 114 in the direction parallel to the axial direction I by the elastic force of the spring 150, and the locking teeth 132, 134 can only be accommodated in the direction parallel to the axial direction I by the elastic force of the spring 150. Specifically, the locking teeth 132 and 134 abut against the end surface of the first tooth 111 in a direction parallel to the axial direction I, and some of the engaging teeth 131 also abut against the end surface of the first tooth 111 in a direction parallel to the axial direction I. Each protrusion 135 moves along the circumferential direction C into the plurality of grooves 117 or between two first teeth 111 in the circumferential direction C, but is not blocked by the first teeth 111 in the circumferential direction C. The driving member 140 is then released from contact with the locking member 130 and only contacts the first connecting seat 110, spaced apart from the locking member 130 in the axial direction I. During this process, the relative rotation between the first connecting seat 110 and the second connecting seat 120 is not blocked in the circumferential direction C until the first tooth 111 with the notch 116 moves along the retraction direction D1 to one side of the protrusion 135, as shown in FIG9 . FIG9 is a partial sectional view of the locking joint 100 in the unlocked state along the circumferential direction. The schematic diagram cuts the locking joint 100 at the latching tooth 131 provided with the protrusion 135 and the first tooth 111 provided with the recess 116 (the two first teeth 111 provided with the recess 116 will simultaneously move to one side of the two protrusions 135 along the retraction direction D1. The following only takes one of the first teeth 111 and the corresponding protrusion 135 as an example for explanation). When the first tooth 111 provided with the recess 116 continues to move along the retraction direction D1 from the state shown in FIG9 , the first tooth 111 provided with the recess 116 will be blocked by the protrusion 135 along the retraction direction D1, and will further overcome the elastic force of the spring 150 along the guiding inclined surface 138 of the protrusion 135 (that is, further compress the spring 150, further push the locking member 130 toward the second connecting seat 120, and reduce the hard interference between the first tooth 111 provided with the recess 116 and the protrusion 135). The user moves in the direction of the axial direction I to the end surface of the protrusion 135 (i.e., the abutment surface 160). During this process, the user will feel the resistance of the push handle 10 due to the interference between the protrusion 135 and the first tooth 111, which indicates that the locking joint 100 is about to reach the second locking state and the frame is about to reach the locked and retracted state. Until the recess 116 is opposite to the protrusion 135 in a direction parallel to the axial direction I, the locking member 130 is pushed to the recess 116 by the elastic force of the spring 150. 10 , and the user can also feel that the protrusion 135 is pushed into the recess 116 by the elastic force of the spring 150, so that the locking joint 100 has reached the second locking state. The push handle 10 and linkage rod 20 in FIG11 correspond to the folded locking state of the frame in FIG3 and the second locking state of the locking joint 100 in FIG10, and are translated and opened to show the internal structure. As shown in FIG10 and FIG11, when the locking joint 100 is in the second locking state, the two protrusions 135 of the locking member 130 are received in the two recesses 116 of the first connecting seat 110 one by one, and the blocking surface 118 is blocked by the abutting surface 139 along the expansion direction D2, thereby limiting the rotation of the second connecting seat 120 provided with the recess 116 and the push handle 10 along the expansion direction D2 relative to the locking member 130 provided with the protrusion 135 and the linkage rod 20 along the expansion direction D2, that is, limiting the push handle 10 relative to the linkage rod 20. 0 pivots in the expansion direction D2. However, because the protrusion 135 is only provided on the side of the corresponding engaging tooth 131 in the expansion direction D2, and not on the side of the corresponding engaging tooth 131 in the retracted direction D1, and because the remaining first teeth 111 are each provided with a recess 117 for receiving the protrusion 135, the first tooth 111 with the recess 116 can still rotate in the retracted direction D1 relative to the protrusion 135. This means that the push handle 10 can still rotate in the retracted direction D1 relative to the linkage rod 10 and the locking member 130. At the same time, the protrusion 135 (specifically, the abutment surface 160) is blocked by the stop surface 119 in a direction parallel to the axial direction I, limiting the protrusion 135 from further protruding into the first connecting seat 110 in a direction parallel to the axial direction I. This results in the locking member 130 extending into the first connecting seat 110 to a depth that is significantly less than the depth of the locking member 130 extending into the first connecting seat 110 when the locking joint 100 is in the first locked state. In this closed and locked state, when the push handle 10 is pushed along the expansion direction D2, due to the small depth of the recess 116, the depth of the locking member 130 extending into the first connecting seat 110 is also small. Even if the blocking surface 118 and the abutment surface 139 abut against each other along the circumferential direction C, it will cause a certain obstruction to the movement of the push handle 10. However, since the depth of the abutment between the two is not large, as long as the push handle 10 is pivoted in the opposite direction D2 of the circumferential direction C (that is, the expansion direction D2), the first tooth 111 with the recess 116 can be moved along the expansion direction D2 and the direction parallel to the axial direction I to the outer side of the end surface of the protrusion 135 in the direction parallel to the axial direction I (so that the lock The fixed member 130 moves toward the second connecting seat 120 and compresses the spring 150, reducing the hard interference between the first tooth 111 with the recess 116 and the protrusion 135), and then passes over the protrusion 135 and moves to the side of the circumferential direction C where the protrusion 135 is provided with a guide slope 138, that is, the first tooth 111 with the recess 116 abuts against the protrusion 135 along the circumferential direction C, and the protrusion 135 disengages from the recess 116. At this time, the locking joint 100 returns to the unlocked state. If the push handle 10 is continued to be pushed along the expansion direction D2, the locking joint 100 can be restored to the first locked state, and the frame can be restored to the expanded state, so that the push handle 10 can no longer pivot relative to the linkage rod 20. In other embodiments, the stop surface 119 can be formed on the end surface of the first tooth 111 provided with the recess 116 in the direction parallel to the axial direction I (that is, located on the side of the blocking surface 118 in the positive direction D1 of the circumferential direction C), and the abutment surface 160 can be formed on the end surface of the meshing tooth 131 provided with the protrusion 135 in the direction parallel to the axial direction I (that is, located on the side of the abutment surface 139 in the positive direction D1 of the circumferential direction C). When the locking joint 100 is in the second locking state, the protrusion 135 is also accommodated in the recess 116, but the end surface of the protrusion 135 in the direction parallel to the axial direction I does not abut the surface of the first tooth 111 located on the side of the recess 116 in the direction parallel to the axial direction I, but the stop surface 119 abuts the abutment surface 160 in the direction parallel to the axial direction I, which can also limit the engagement depth between the locking member 130 and the first connecting seat 110. In other embodiments, two protrusions 135 can also be provided on the two first teeth 111, and two recesses 116 can be provided on the two engaging teeth 131, and multiple grooves 117 can be provided on the remaining multiple engaging teeth 131 and locking teeth 132 and 134. By the abutment between the abutment surface 139 on the protrusion 135 and the blocking surface 118 (in this case, the blocking surface 118 is provided on the side of the protrusion 135 in the opposite direction D2 of the circumferential direction C, and the abutment surface 139 is provided on the side of the recess 116 in the opposite direction D2 of the circumferential direction C), the push handle 10 is restricted from moving relative to the linkage rod 20 along the expansion direction D2, and the end surface of the protrusion 135 in the direction parallel to the axial direction I (that is, the abutment surface 160) abuts against the abutment surface 119 of the recess 116 to limit the engagement depth between the locking member 130 and the first connecting seat 110. 12 to 18 show another embodiment of a locking joint 100 according to the present disclosure. To avoid repetition, the same parts of this embodiment as those of the embodiment of FIG. 1 to 11 will not be described again. Figures 12 and 13 are exploded views of a locking joint 100A according to another embodiment. Figure 14 is a three-dimensional view of a first connecting seat 110A and a locking member 130A according to another embodiment, wherein, in order to illustrate the internal structure of the first connecting seat 110A and the locking member 130A, the first connecting seat 110A and the locking member 130A are translated open, and the locking member 130A is rotated at a certain angle. According to this embodiment, as shown in Figures 12, 13 and 14, the two engaging portions 135A of the locking member 130A are two ribs 135A, which will be described below as ribs 135A. The two ribs 135A are arranged one-to-one on two engaging teeth 131A spaced apart along the circumferential direction C, and the two engaging teeth 131A are arranged approximately 180° apart. Specifically, the rib 135A protrudes from the end surface of the corresponding engaging tooth 131A, which is away from the second connecting seat 120A, toward the first connecting seat 110A in a direction parallel to the axial direction I. It is located at the radially outer end of the corresponding engaging tooth 131A and protrudes radially beyond the radially outer end of the engaging tooth 131A. In other words, the rib 135A is not radially continuous along the entire end surface of the corresponding engaging tooth 131A, which is away from the second connecting seat 120A in a direction parallel to the axial direction I. Alternatively, the rib 135A may be provided on the locking tooth 132A and the locking tooth 134A. The guide bevel 138A, the abutting surface 139A and the abutting surface 160A of the locking member 130A are all formed on the surface of the rib 135A. Specifically, the guide bevel 138A is formed on the surface of the rib 135A on the side of the opposite direction D2 of the circumferential direction C, and is inclined to the radial direction and the circumferential direction C, while the abutting surface 139A is formed on the surface of the rib 135A on the side of the positive direction D1 of the circumferential direction C, and is also inclined to the radial direction and the circumferential direction C, that is, the abutting surface 139A is also set as an inclined surface, and the inclination angle of the guide bevel 138A is greater than the inclination angle of the abutting surface 139A, and the abutting surface 160A is formed on the end face of the rib 135A in the direction parallel to the axial direction I. Specifically, the guide bevel 138A and the abutment surface 139A are connected to each other, and an obtuse angle is formed therebetween. Furthermore, the guide bevel 138A and the abutment surface 139A are both parallel to the axial direction I, while the abutment surface 160A is perpendicular to the axial direction I. As shown in FIG14 , the first connecting seat 110A has two limiting portions 116A spaced apart along the circumferential direction C and formed on the inner circumference of the circular accommodating portion. The two limiting portions 116A (configured as protrusions 116A, hereinafter described as protrusions 116A) are provided in a one-to-one correspondence on two first teeth 111A spaced apart along the circumferential direction C. The two first teeth 111A are spaced approximately 180 degrees apart.The protrusion 116A protrudes from the end surface of the first tooth 111A close to the second connecting seat 120A toward the second connecting seat 120A in a direction parallel to the axial direction I, and is arranged on the side of the corresponding first tooth 111A in the positive direction D1 of the circumferential direction C, but is not arranged on the side of the corresponding first tooth 111A in the reverse direction D2 of the circumferential direction C, that is, the protrusion 116A does not cover the entire end surface of the corresponding first tooth 111 along the circumferential direction C, and the protrusion 116A extends beyond the corresponding first tooth 111A along the positive direction D1 of the circumferential direction C, but does not extend to the adjacent first tooth 111A, and the protrusion 116A is radially arranged at the end portion of the corresponding first tooth 111A (close to the circular accommodating portion of the first connecting seat 110A), and the protruding length of the protrusion 116A in the direction parallel to the axial direction I is less than or equal to the protruding length of the rib 135A in the direction parallel to the axial direction I. As shown in Figure 14, in this embodiment, the blocking surface 118A of the first connecting seat 110A is formed on the surface of the protrusion 116A on the side of the opposite direction D2 of the circumferential direction C, and the blocking surface 118A is inclined with respect to the circumferential direction C and the radial direction. Specifically, the inclination angle of the blocking surface 118A is consistent with that of the abutment surface 139A, and the blocking surface 118A is also parallel to the axial direction I. As shown in Figure 14, in this embodiment, the stop surface 119A of the first connecting seat 110A is formed on the end surface of the first tooth 111A provided with the protrusion 116A close to the second connecting seat 120A in a direction parallel to the axial direction I, and is located on the side of the blocking surface 118A in the opposite direction D2 of the circumferential direction C. The stop surface 119A extends in a direction intersecting with the axial direction I. Specifically, the stop surface 119A extends in a direction perpendicular to the axial direction I, and the blocking surface 118A and the stop surface 119A are perpendicular to each other. As shown in FIG14 , in this embodiment, in addition to the blocking surface 118A and the abutting surface 119A, which are consistent with the embodiments of FIGS. 1 to 10 , the first connecting seat 110A further comprises a guide slope S. The guide slope S is formed on the side of the projection 116A in the positive direction D1 of the circumferential direction C and is inclined relative to the circumferential direction C and the radial direction. The guide slope S is configured to abut against the guide slope 138A in the positive direction D1 of the circumferential direction C when the locking joint 100 is in the unlocked state, thereby moving the projection 116A from the guide slope 138A side of the rib 135A to the side of the abutting surface 139A of the rib 135A in the positive direction D1 of the circumferential direction C. Specifically, the guide slope S has the same inclination angle as the guide slope 138A, and at least a portion of the guide slope S extends beyond the first tooth 111A in the positive direction D1 of the circumferential direction C. As shown in Figure 14, in this embodiment, in addition to the first tooth 111A provided with the protrusion 116A, on the other first teeth 111A, a groove 117A is formed by being recessed from the end surface of each first tooth 111A close to the second connecting seat 120A in a direction parallel to the axial direction I toward the side away from the second connecting seat 120A in a direction parallel to the axial direction I. The groove 117A penetrates the corresponding entire first tooth 111A along the circumferential direction C, but does not penetrate the corresponding entire first tooth 111A radially, that is, the bottom of the groove 117A is not the end surface of the first tooth 111A closest to the second connecting seat 120A in a direction parallel to the axial direction I. The depth of the groove 117A is equal to or greater than the protruding length of the rib 135A. The groove 117A is used to make way for the rib 135A to move along the circumferential direction C when the locking joint 100A is in the unlocked state. As shown in FIG. 14 , in this embodiment, the height of the rib 135A is preferably equal to the height of the bump 116A. Figure 15 is a cross-sectional view of a locking member 130A according to another embodiment. According to this embodiment, the locking member 130A further comprises two recesses 137A, formed one-to-one in the two engaging teeth 131A provided with the ribs 135A. Each recess 137A is recessed parallel to the axial direction I, extending from the end face of the engaging tooth 131A facing away from the second connecting seat 120A, toward one side of the second connecting seat 120A. The recess 137A is radially formed between the free end of the rib 135A and the corresponding engaging tooth 131A, thereby enhancing the radial elastic deformation of the ribs 135A. FIG16 is a partial schematic diagram of a locking joint 100A in an unlocked state along a circumferential direction C according to another embodiment. The schematic diagram illustrates a latching tooth 131A with a rib 135A and a protrusion 116A located on the inner circumference of the first connecting seat 110A. In the state shown in FIG16 , the frame is about to reach the retracted locked state and the locking joint 100A is about to reach the second locked state. As the protrusion 116A continues to move in the retracted direction D1 from the state shown in FIG16 , the guide slope S extending in the circumferential direction C will slide against the guide slope 138A, causing the protrusion 116A to elastically deform the free end of the rib 135A in the radial direction, facilitating the sliding of the protrusion 116A over the rib 135A in the retracted direction D1. During this process, the user will feel resistance on the push handle 10A due to the contact between the rib 135A and the protrusion 116A, indicating that the locking joint 100A is about to reach the second locked state and the frame is about to reach the locked retracted state. Figure 17 is a three-dimensional view of the first connecting seat 110A, the locking member 130A, and the spring 150A according to another embodiment. The locking member 130A abuts against the end face of the first tooth 111A of the first connecting seat 110A using the elastic force of the spring 150A in the spring receiving portion 136A. The abutting surface 139A of the rib 135A abuts against the blocking surface 118A of the protrusion 116A (the rib 135A and the protrusion 116A are circumferentially abutted), so that the rib 135A and the protrusion 116A are engaged, thereby limiting the protrusion 116A from pivoting relative to the rib 135A in the deployment direction D2. This also limits the push handle 10 from pivoting relative to the linkage rod 20 in the deployment direction D2. At this time, the locking joint 100A is in the second locking state, and the frame is in the retracted locking state. However, when the first connecting base 110A rotates along the folding direction D1, the rib 135A and the protrusion 116A are not affected by each other, and the push handle 10 can be further folded. Fig. 18 is a perspective view of a locking joint 100A according to another embodiment. The state of each component in Fig. 18 corresponds to that in Fig. 11, wherein the components are opened in translation to show the internal structure. As shown in Figures 17 and 18, when the locking joint 100A is in the second locking state and the frame is in the folded and locked state, when the first connecting seat 110A rotates along the expansion direction D2, the abutment surface 139A with a larger slope and the blocking surface 118A abut against each other, making it difficult to expand easily. However, since the length of the protrusion 116A protruding in the direction parallel to the axial direction I is small, and the protrusion length of the rib 135A in the direction parallel to the axial direction I is greater than or equal to the length of the protrusion 116A protruding in the direction parallel to the axial direction I, when the user forcefully rotates the first connecting seat 110A along the expansion direction D2, the protrusion 116A can also radially drive the free end of the rib 135A to elastically deform radially, so as to guide the protrusion 116A to slide over the rib 135A along the expansion direction D2, so that the abutment surface 139A with a larger slope and the blocking surface 118A no longer abut against each other, and the locking joint 100A returns to the unlocked state. At the same time, in the states shown in Figures 17 and 18, the abutment surface 160A of the rib 135A will also be blocked by the stop surface 119A in a direction parallel to the axial direction I, and the rib 135A is restricted from further protruding into the first connecting seat 110A in a direction parallel to the axial direction I, so that the depth of the locking member 130A extending into the first connecting seat 110A is less than the depth of the locking member 130A extending into the first connecting seat 110A when the locking joint 100A is in the first locking state. Since the present application can be implemented in various forms without departing from the spirit and essence of the present application, it should be understood that the above embodiments are not limited to any of the aforementioned details, but should be interpreted in the broadest sense within the scope defined by the scope of the patent application. Therefore, all changes that fall within the scope of the patent application or its equivalent should be covered by the scope of the patent application. 1: Child carrier 10, 10A: Push handle 11: Operating element 20, 20A: Linkage rod 30: Rider 40: Front leg assembly 50: Rear leg assembly 60: Seat assembly 70: Armrest 100, 100A: Locking joint 110 110A: First connecting seat 111, 111A: First teeth 112, 112A: Pin 113, 113A: Driving portion 114, 114A: Locking portion 115, 115A: Locking portion 116, 116A: Limiting portion, notch, protrusion 117, 117A: Groove 118, 118A: Blocking surface 119, 119A: Stop surface S: Guide slope 120, 120A: Second connecting seat 121, 121A: Second teeth 122, 122A: Locking portion 123, 123A: Locking portion 130, 130A: Locking member 131, 131A: Engaging teeth 132, 132A: Locking tooth 133, 133A: Through hole 134, 134A: Locking tooth 135, 135A: Engaging portion, protrusion, rib 136, 136A: Spring accommodating portion 137A: Recess 138, 138A: Guide slope 139, 139A: Abutment surface 160, 160A: Contact surface 140, 140A: Driving member 141, 141A: Through hole 142, 142A: Driving portion 150, 150A: Elastic member, spring 200: Frame joint I: Axial direction C: Circumferential direction D1: Retraction direction, positive direction of circumferential direction C D2: Deployment direction, negative direction of circumferential direction C FIG1 is a side view of a frame of a child carrier according to the present disclosure in an unfolded state; FIG2 is a front perspective view of the child carrier according to the present disclosure in an unfolded state; FIG3 is a rear perspective view of the frame of the child carrier according to the present disclosure in a folded and locked state; FIG4 is an exploded view of a locking joint according to one embodiment; FIG5 is an exploded view of a locking joint according to one embodiment; FIG6 is a perspective view of a first connecting socket according to an embodiment; FIG7 is a perspective view of a locking member according to an embodiment; 8 is a cross-sectional view of a locking joint according to an embodiment when the frame is in an expanded state; 9 is a partial cross-sectional view cut along the circumferential direction of the locking joint in an unlocked state according to one embodiment; FIG10 is a cross-sectional view of the locking joint according to one embodiment when the frame is in a folded and locked state, wherein the driving member is hidden; FIG11 is a perspective view of a locking joint according to one embodiment; FIG12 is an exploded view of a locking joint according to another embodiment; FIG13 is an exploded view of a locking joint according to another embodiment; FIG14 is a perspective view of a first connecting seat and a locking member according to another embodiment; FIG15 is a cross-sectional view of a locking member according to another embodiment; 16 is a partial schematic diagram along the circumferential direction of a locking joint in an unlocked state according to another embodiment; FIG17 is a perspective view of a first connecting seat, a locking member and a spring according to another embodiment; and 18 is a perspective view of a locking joint according to another embodiment. 10: Push handle 20: Linkage rod 110: First connecting seat 111: First tooth 112: Pin 114: Locking part 115: Locking part 116: limiting portion, notch 117: Groove 120: Second connecting seat 121: Second tooth 122: Locking part 123: Locking part 130: Locking piece 131: Engaging teeth 132: Locking tooth 134: Locking tooth 135: snap-fit ​​portion, protrusion 140: driving member 141:Piercing 142: Drive unit C: Circumferential D1: Folding direction, positive direction of circumferential direction C D2: Development direction, opposite to circumferential direction C I: Axial

Claims

1. A locking joint, comprising: First connecting seat; The second connecting seat, the first connecting seat and the second connecting seat are pivotable about the axial direction and in the circumferential direction; A locking member is disposed between the first connecting seat and the second connecting seat along the axial direction and is movable relative to both along the axial direction and engages with both. The first connecting seat has a limiting portion extending in a direction parallel to the axial direction, and the locking member has an engaging portion extending in a direction parallel to the axial direction. The locking joint has a first locking state and a second locking state. When the locking joint is in the first locking state, the first connecting seat cannot pivot relative to the second connecting seat. When the locking joint is in the second locking state, the locking member engages with the second connecting seat, and the engaging portion engages with the limiting portion. The first connecting seat can pivot relative to the second connecting seat in the positive circumferential direction, but cannot pivot relative to the second connecting seat in the opposite circumferential direction.

2. The locking joint as described in claim 1, wherein: The first connecting seat has a plurality of first teeth spaced apart along the circumferential direction on its inner periphery, and the second connecting seat has a plurality of second teeth spaced apart along the circumferential direction on its inner periphery. The locking member has a plurality of locking teeth spaced apart along the circumferential direction on its outer periphery and capable of engaging with the first teeth and the second teeth. The limiting portion is located on a first tooth near the end face of the second connecting seat in a direction parallel to the axial direction, and the engaging portion is located on a locking tooth away from the end face of the second connecting seat in a direction parallel to the axial direction. The first connecting seat also has a blocking surface located on one side of the limiting portion in the circumferential direction and on the same first tooth as the limiting portion. The locking member also has a contact surface located on one side of the engaging portion in the circumferential direction and on the same locking tooth as the engaging portion. When the locking member engages with the second connecting seat and the engaging portion engages with the limiting portion, the plurality of locking teeth engage with the plurality of second teeth in an alternating manner along the circumferential direction, and at least one locking tooth is opposite to at least one first tooth in a direction parallel to the axial direction. The blocking surface and the abutting surface abut against each other along the circumferential direction, and the abutting surface is located on the opposite side of the blocking surface in the circumferential direction, so as to restrict the limiting portion from pivoting relative to the engaging portion in the opposite direction of the circumferential direction.

3. The locking joint as described in claim 2, wherein: The engaging portion protrudes from the end face of the corresponding locking tooth away from the second connecting seat toward the first connecting seat in a direction parallel to the axial direction, and the abutting surface is located on the surface of the engaging portion on the positive side of the circumferential direction.

4. The locking joint as described in claim 3, wherein: The engaging portion is located on the opposite side of the corresponding tooth in the circumferential direction and does not extend to the positive side of the corresponding tooth in the circumferential direction; the limiting portion is recessed from the end face of the corresponding first tooth near the second connecting seat in a direction parallel to the axial direction toward the side away from the second connecting seat, the limiting portion is located on the opposite side of the corresponding first tooth in the circumferential direction and penetrates the corresponding first tooth in the opposite direction of the circumferential direction, the blocking surface is located on the positive side of the limiting portion in the circumferential direction; when the limiting portion and the engaging portion are engaged, the engaging portion is at least partially embedded in the limiting portion.

5. The locking joint as described in claim 4, wherein: Both the blocking surface and the contact surface are parallel to the axial direction.

6. The locking joint as described in claim 4, wherein: At least one of the first connecting seat and the locking member is provided with a guide slope, the guide slope being used to guide the first tooth with the limiting portion to pass over the engaging portion in the positive circumferential direction; the guide slope is provided on the surface of the first tooth with the limiting portion on the positive circumferential direction side, and is inclined to the direction parallel to the axial direction and the circumferential direction; and / or, the guide slope is provided on the surface of the engaging portion on the opposite circumferential direction side, and is inclined to the direction parallel to the axial direction and the circumferential direction.

7. The locking joint as described in claim 4, wherein: The first connecting seat is further provided with a stop surface, which is located on one side of the blocking surface in the circumferential direction, and the stop surface and the blocking surface are located in the same first tooth; the locking member is further provided with an abutment surface, which is located on one side of the contact surface in the circumferential direction, and the abutment surface and the contact surface are located in the same locking tooth; when the locking member is engaged with the second connecting seat, and the engaging part is engaged with the limiting part, the stop surface and the abutment surface abut against each other in a direction parallel to the axial direction.

8. The locking joint as described in claim 7, wherein: The abutting surface is located on the opposite side of the blocking surface in the circumferential direction and on the side of the limiting portion in the direction parallel to the axial direction; the abutting surface is located on the opposite side of the contact surface in the circumferential direction and on the side of the engaging portion in the direction parallel to the axial direction; or, the abutting surface is located on the positive side of the blocking surface in the circumferential direction and the abutting surface is located on the positive side of the contact surface in the circumferential direction.

9. The locking joint as described in claim 3, wherein: The engaging portion is located at the radially outer end of the corresponding tooth; the limiting portion protrudes from the end face of the corresponding first tooth near the second connecting seat in a direction parallel to the axial direction toward the second connecting seat, the limiting portion is located on the positive side of the corresponding first tooth in the circumferential direction, and does not extend to the opposite side of the corresponding first tooth in the circumferential direction, the blocking surface is located on the surface of the limiting portion on the opposite side of the circumferential direction; when the limiting portion and the engaging portion are engaged, the engaging portion abuts against the limiting portion in the circumferential direction.

10. The locking joint as described in claim 9, wherein: Both the blocking surface and the contact surface are inclined to the radial and circumferential directions.

11. The locking joint as described in claim 10, wherein: At least one of the first connecting seat and the locking member is provided with a guide slope, the guide slope being used to guide the limiting part to pass over the engaging part in the positive direction of the circumference; the guide slope is provided on the surface of the limiting part on the positive side of the circumference and is inclined to the radial and the circumference; and / or, the guide slope is provided on the surface of the engaging part on the opposite side of the circumference and is inclined to the radial and the circumference.

12. The locking joint as described in claim 11, wherein: The tilt angle of the contact surface is greater than the tilt angle of the guide slope.

13. The locking joint as described in claim 9, wherein: The locking member has a recessed portion, which is recessed from the end face of the engaging tooth away from the second connecting seat in a direction parallel to the axial direction, and is formed radially between the engaging portion and the corresponding engaging tooth.

14. The locking joint as described in claim 9, wherein: The first connecting seat is further provided with a stop surface, which is located on the end face of the second connecting seat in a direction parallel to the axial direction of the first tooth where the limiting part is located, and is located on the side of the blocking surface opposite to the circumferential direction; the locking member is further provided with a contact surface, which is located on the end face of the engaging part away from the second connecting seat in a direction parallel to the axial direction; when the locking member engages with the second connecting seat, and the engaging part engages with the limiting part, the stop surface and the contact surface abut against each other in a direction parallel to the axial direction.

15. The locking joint as described in claim 3, wherein: In addition to the first tooth with the limiting portion, each of the remaining first teeth has a groove. The groove is formed in a direction parallel to the axial direction from the end face of the corresponding first tooth near the second connecting seat toward the side away from the second connecting seat. The groove extends circumferentially through the corresponding first tooth and is used to receive the engaging portion in a direction parallel to the axial direction.

16. The locking joint as described in claim 15, wherein: The depth of the groove is greater than or equal to the length of the engaging portion.

17. A child vehicle, the child vehicle comprising: Frame; And a locking joint as claimed in any one of claims 1 to 16, wherein the frame includes a push handle and a linkage rod pivotally connected to the push handle via the locking joint, the push handle being connected to the first connecting seat, the linkage rod being connected to the second connecting seat, the push handle pivoting toward the linkage rod in the positive direction of the circumference to achieve retraction between the push handle and the linkage rod, and the push handle pivoting away from the linkage rod in the opposite direction of the circumference to achieve deployment between the push handle and the linkage rod.

Images