Patent Description:
Baby strollers are widely used in infants' travel. As the two-child policy is carried out in society, there are more and more two-child families. However, currently, most baby strollers each have one seat or two seats (generally designed for twin families). With the successive birth of children, it is necessary to purchase a baby stroller with two seats after the purchase of a baby stroller with one seat.

The applicant has been committed to the research and development of baby strollers. Previously, a baby stroller has been developed to implement the free switching between a single seat and double seats in the stroller. A retractable chassis of a stroller body is retracted by means of a retractable device of the retractable chassis, so that an area of the retractable chassis of the stroller body is reduced, and a riding space required for the single seat/double seats can be freely switched. However, the applicant has received reflection from the market that a retractable upper enclosure of this type of baby stroller cannot be locked by itself after the retractable upper enclosure is extended or retracted. When a single seat is provided, the retractable upper enclosure is prone to being extended forward under the action of an external force, which makes the retractable upper enclosure unstable and affects the safety. Now it is necessary to design a baby stroller in which a retractable upper enclosure and a retractable chassis extend or retract simultaneously and can be locked, to solve the existing outstanding problems.

Patent document <CIT> discloses a baby carriage framework capable of adding and reducing the accommodation space and the number of seats which comprises a pair of front supports, a pair of rear supports, a hand-pushed frame, an upper retractable support, a lower retractable support and a folding mechanism.

Patent document <CIT> discloses a trolley chassis telescopic device.

Patent document <CIT> discloses a child cart, which comprises a cart frame, a first seat, a second seat and wheels arranged on the lower part of the cart frame.

Patent document <CIT> discloses an adapter which removably mounts to a stroller or other child-supporting device, and a range of different child carriers which can be removably mounted to the adapter and thus the stroller.

An objective of the present invention is to provide a baby stroller capable of implementing free switching between a single seat and double seats, which re-optimizes a retractable mechanism of a retractable upper enclosure, so that the structure of the retractable upper enclosure is more stable after the extension or retraction, thereby solving the problem of insufficient safety mentioned in the background art.

To achieve the above objective, the present invention provides the following technical solution: a baby stroller capable of implementing free switching between a single seat and double seats, comprising a stroller body, wherein a retractable chassis is provided at the bottom of the stroller body, a retractable upper enclosure is mounted at a middle portion of the stroller body, the retractable upper enclosure comprises a fixed rod and a telescopic rod, the fixed rod and the telescopic rod each are hollow in a U shape, universal wheels are mounted at the bottom of the retractable chassis, the telescopic rod is slidably connected in the fixed rod, an end of the fixed rod is provided with a female locking buckle for positioning the telescopic rod, a sub-locking buckle is arranged in the telescopic rod, and a check block is fixed to an end of the telescopic rod; and
the female locking buckle comprises a housing, the housing is fixed to an end of the fixed rod by means of a screw, the sub-locking buckle comprises a lock block, the lock block is mounted in an inner cavity of the telescopic rod, two lock blocks are provided, each of the lock blocks is internally provided with a positioning block, an inner cavity of the housing is provided with a limiting mechanism for slidably limiting the lock block, and the bottom of the housing is provided with a trigger mechanism of the positioning block.

Preferably, the limiting mechanism comprises a sliding groove, the sliding groove is provided in the inner cavity of the housing, an outer wall of the telescopic rod is provided with an integrally formed protruding strip, and the protruding strip is slidably connected in the sliding groove.

Preferably, the trigger mechanism comprises a spring button, a double-layer mounting plate is connected to a lower surface of the housing by means of a screw, the spring button is mounted on a lower surface of the mounting plate, a center of the mounting plate and an outer wall of the bottom of the fixed rod each are provided with a through groove for the spring button to run through, an upper surface of an end of the mounting plate is provided with a locking fastener, and two ends of the spring button are provided with bolts.

Preferably, the locking fastener comprises an inversely L-shaped buckle, a lower surface of the lock block is provided with an integrally formed arc-shaped protruding block, an end of the protruding block is provided with a fastening position, an end of the buckle penetrates through outer walls of the fixed rod and a movable rod, and a transverse plate of the buckle is tightly hooked at the fastening position.

Preferably, each of the positioning blocks is arranged in the shape of a rectangular strip, an integrally formed wedge-shaped ejector block is provided at the bottom of the positioning block, the ejector blocks of the two positioning blocks are arranged in a mirrored manner, and a lifting groove for the ejector block to vertically slide is formed in each of the lock blocks.

Preferably, the lifting groove is located above the through groove, the check block is arranged in the shape of a column, and an end of the check block is provided with an integrally formed boss.

Compared with the prior art, the present invention has the following beneficial effects:
according to the present invention, by arranging a spring button, a sub-locking buckle, and a female locking buckle, the sub-locking buckle is locked with the female locking buckle when the spring button is not pressed, and the telescopic rod of the retractable upper enclosure does not extend out of the fixed rod, thereby improving the stability of the retractable upper enclosure after locking, and improving the safety of the baby stroller; and according to the device, two sub-locking buckles are arranged, so that the baby stroller can be locked when the retractable upper enclosure is retracted for sitting by one person or extended for sitting by two persons, the arrangement of the button makes the locking after extension or retraction convenient to activate and deactivate, and thus the retractable upper enclosure can be easily extended or retracted and locked stably.

In the <FIG>. Stroller body; <NUM>. Retractable chassis; <NUM>. Retractable upper enclosure; <NUM>. Fixed rod; <NUM>. Telescopic rod; <NUM>. Universal wheel; <NUM>. Female locking buckle; <NUM>. Sub-locking buckle; <NUM>. Check block; <NUM>. Housing; <NUM>. Lock block; <NUM>. Positioning block; <NUM>. Trigger mechanism; <NUM>. Sliding groove; <NUM>. Protruding strip; <NUM>. Spring button; <NUM>. Mounting plate; <NUM>. Through groove; <NUM>. Buckle; <NUM>. Protruding block; <NUM>. Fastening position; <NUM>. Bolt; <NUM>. Ejector block; <NUM>. Lifting groove; <NUM>.

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Apparently, the embodiments described are merely some rather than all of the embodiments of the present invention.

Referring to <FIG>, the present invention provides a technical solution: a baby stroller capable of implementing free switching between a single seat and double seats, comprising a stroller body <NUM>, wherein a retractable chassis <NUM> is provided at the bottom of the stroller body <NUM>, a specific structure of the retractable chassis <NUM> pertains to the prior art, and for details, refer to a retractable device of a stroller chassis in Chinese patent <CIT>, in which a retractable upper enclosure <NUM> is mounted at a middle portion of the stroller body <NUM>, the retractable upper enclosure <NUM> comprises a fixed rod <NUM> and a telescopic rod <NUM>, the fixed rod <NUM> and the telescopic rod <NUM> each are hollow in a U shape, universal wheels <NUM> are mounted at the bottom of the retractable chassis <NUM>, the telescopic rod <NUM> is slidably connected in the fixed rod <NUM>, an end of the fixed rod <NUM> is provided with a female locking buckle <NUM> for positioning the telescopic rod <NUM>, a sub-locking buckle <NUM> is arranged in the telescopic rod <NUM>, and a check block <NUM> is fixed to an end of the telescopic rod <NUM>.

When the telescopic rod <NUM> is pulled manually, the retractable upper enclosure <NUM> is extended; and when the telescopic rod <NUM> is pushed inward, the retractable upper enclosure <NUM> is retracted, so that the switching between the single seat and the double seats is implemented. During extension or retraction of the telescopic rod <NUM>, the sub-locking buckle <NUM> in the telescopic rod <NUM> is clamped in the female locking buckle <NUM>, so that the structure after the extension or retraction is more stable.

The female locking buckle <NUM> comprises a housing <NUM>, the housing <NUM> is fixed to an outer wall of an end of the fixed rod <NUM> by means of a screw, the sub-locking buckle <NUM> comprises a lock block <NUM>, the lock block <NUM> is mounted in an inner cavity of the telescopic rod <NUM>, and two lock blocks <NUM> are provided. As shown in <FIG> and <FIG>, the two lock blocks <NUM> are fixed in the telescopic rod <NUM>, each of the lock blocks <NUM> is internally provided with a positioning block <NUM>, and an inner cavity of the housing <NUM> is provided with a limiting mechanism for slidably limiting the lock block <NUM>. As shown in <FIG> and <FIG>, the bottom of the housing <NUM> is provided with a trigger mechanism <NUM> of the positioning block <NUM>.

By arranging the two lock blocks <NUM>, when the telescopic rod <NUM> is extended, the lock block <NUM> at one end of the telescopic rod <NUM> moves into the female locking buckle <NUM>, a spring button <NUM> is pressed, and the lock block <NUM> is fastened by the trigger mechanism <NUM> at the bottom of the housing <NUM>, thereby implementing extension positioning; and
when the telescopic rod <NUM> is retracted into the fixed rod <NUM>, the lock block <NUM> at the other end of the telescopic rod <NUM> enters the fixed rod <NUM>, and the lock block <NUM> is fastened again by the trigger mechanism <NUM> at the bottom of the housing <NUM>, thereby implementing the locking after the retraction, so that the retractable upper enclosure <NUM> of the baby stroller in the two states can be stabilized.

The limiting mechanism comprises a sliding groove <NUM>, the sliding groove <NUM> is provided in the inner cavity of the housing <NUM>, an outer wall of the telescopic rod <NUM> is provided with an integrally formed protruding strip <NUM>, and the protruding strip <NUM> is slidably connected in the sliding groove <NUM>.

By providing the sliding groove <NUM>, the protruding strip <NUM> slides in the sliding groove <NUM>, to play a guiding role when the telescopic rod <NUM> extends or retracts, and improve the smoothness of the extension or retraction of the retractable upper enclosure <NUM>.

The trigger mechanism <NUM> comprises a spring button <NUM>, and a double-layer mounting plate <NUM> is connected to a lower surface of the housing <NUM> by means of a screw. The double-layer mounting plate <NUM> is fixed to the housing <NUM>, to provide a mounting position for the trigger mechanism <NUM>, so as to brake the lock block <NUM> extending into the housing <NUM>. The spring button <NUM> is mounted on a lower surface of the mounting plate <NUM>, a center of the mounting plate <NUM> and an outer wall of the bottom of the fixed rod <NUM> each are provided with a through groove <NUM> for the spring button <NUM> to run through, an upper surface of an end of the mounting plate <NUM> is provided with a locking fastener, and two ends of the spring button <NUM> are provided with bolts <NUM>, as shown in <FIG>.

The spring button <NUM> is an existing mechanism, which can be pressed in when pressed once and pop up when pressed again. When the spring button <NUM> is pressed, an end of the spring button <NUM> toward the housing <NUM> extends into the housing <NUM> to push the positioning block <NUM> up, the positioning block <NUM> being a component movably placed in the lock block <NUM>. After the positioning block <NUM> is pushed up, an outer wall of the telescopic rod <NUM> does not protrude, and the telescopic rod <NUM> can be manually and freely pulled; and an ejector block <NUM> is located above the bolt <NUM>, and is no longer attached to a side wall of the bolt <NUM> and no longer causes position interference, so that the telescopic rod <NUM> can be pulled. When the spring button <NUM> is pressed again, the spring button <NUM> is retracted downward, so that the positioning block <NUM> falls, the ejector block <NUM> at the bottom of the positioning block <NUM> is driven to move downward, and a side wall of the ejector block <NUM> is tightly attached to the side wall of the bolt <NUM>.

The locking fastener comprises an inversely L-shaped buckle <NUM>, a lower surface of the lock block <NUM> is provided with an integrally formed arc-shaped protruding block <NUM>, and an end of the protruding block <NUM> is provided with a fastening position <NUM>. As shown in <FIG> and <FIG>, an end of the buckle <NUM> penetrates through outer walls of the fixed rod <NUM> and a movable rod, and a transverse plate of the buckle <NUM> is tightly hooked at the fastening position <NUM>. By providing the buckle <NUM>, the buckle <NUM> is hung at the fastening position <NUM>, so that the telescopic rod <NUM> does not shake.

The positioning block <NUM> is arranged in the shape of a rectangular strip, an integrally formed wedge-shaped ejector block <NUM> is provided at the bottom of the positioning block <NUM>, and the ejector blocks <NUM> of the two positioning blocks <NUM> are arranged in a mirrored manner. That is, inclined planes of the two ejector blocks <NUM> are in different directions, one inclines leftward, and the other inclines rightward. As shown in <FIG> and <FIG>, a lifting groove <NUM> for the ejector block <NUM> to vertically slide is formed in the lock block <NUM>. When the spring button <NUM> is pressed, the positioning block <NUM> moves upward in the lifting groove <NUM>, and drives the ejector block <NUM> to retract into the lock block <NUM>. When the spring button <NUM> is pressed again, the positioning block <NUM> falls down in the lifting groove <NUM> under the action of gravity without the support from the spring button <NUM>, so that the ejector block <NUM> is exposed from the lock block <NUM>, as shown in <FIG>.

The lifting groove <NUM> is located above the through groove <NUM>, the check block <NUM> is arranged in the shape of a column, and an end of the check block <NUM> is provided with an integrally formed boss <NUM>.

During use, when the telescopic rod <NUM> is pulled manually, the retractable upper enclosure <NUM> is extended; and when the telescopic rod <NUM> is pushed inward, the retractable upper enclosure <NUM> is retracted, so that the switching between the single seat and the double seats is implemented. When the telescopic rod <NUM> extends, the spring button <NUM> is first pressed, and the end of the spring button <NUM> toward the housing <NUM> extends into the housing <NUM> to push the positioning block <NUM> up, the positioning block <NUM> being a component movably placed in the lock block <NUM>. After the positioning block <NUM> is pushed up, the outer wall of the telescopic rod <NUM> does not protrude, and the telescopic rod <NUM> can be manually and freely pulled. The telescopic rod <NUM> is manually pulled out, so that the lock block <NUM> located at a bent end of the fixed rod <NUM> is located at the housing <NUM>.

When the spring button <NUM> is pressed again, the spring button <NUM> is retracted downward, so that the positioning block <NUM> falls, the ejector block <NUM> at the bottom of the positioning block <NUM> is driven to move downward, and the side wall of the ejector block <NUM> is tightly attached to the side wall of the bolt <NUM>, thereby avoiding sliding again. In addition, the transverse plate of the L-shaped buckle <NUM> is tightly hooked at the fastening position <NUM>, the fastening position <NUM> being a platform formed by the arc-shaped protruding block <NUM> on the lower surface of the lock block <NUM>. After the fastening, the housing <NUM> is fixed to the lock block <NUM> to prevent the telescopic rod <NUM> from shaking.

According to the present invention, areas of an upper enclosure and a chassis of the stroller are reduced at the same time by means of the upper enclosure of the retractable chassis, so as to implement the retraction of the stroller body, and freely switch between the single seat and the double seats. The retractable upper enclosure has a locking function. By arranging a spring button, a sub-locking buckle, and a female locking buckle, the sub-locking buckle is locked with the female locking buckle when the spring button is not pressed, and the telescopic rod of the retractable upper enclosure does not extend out of the fixed rod, thereby improving the stability of the retractable upper enclosure after locking, and improving the safety of the baby stroller.

Claim 1:
A baby stroller capable of implementing free switching between a single seat and double seats, comprising a stroller body (<NUM>), a retractable chassis (<NUM>), wherein a retractable upper enclosure (<NUM>) is mounted at a middle portion of the stroller body (<NUM>), the retractable upper enclosure (<NUM>) comprises a fixed rod (<NUM>) and a telescopic rod (<NUM>), the fixed rod (<NUM>) and the telescopic rod (<NUM>) each are hollow in a U shape, universal wheels (<NUM>) are mounted at the bottom of the retractable chassis (<NUM>), the telescopic rod (<NUM>) is slidably connected in the fixed rod (<NUM>), an end of the fixed rod (<NUM>) is provided with a female locking buckle (<NUM>) for positioning the telescopic rod (<NUM>), a sub-locking buckle (<NUM>) is arranged in the telescopic rod (<NUM>), and a check block (<NUM>) is fixed to an end of the telescopic rod (<NUM>); and the sub-locking buckle (<NUM>) comprises a lock block (<NUM>), the lock block (<NUM>) is mounted in an inner cavity of the telescopic rod (<NUM>), two lock blocks (<NUM>) are provided, each of the lock blocks (<NUM>) is internally provided with a positioning block (<NUM>),
characterized in that
the retractable chassis (<NUM>) is provided at the bottom of the stroller body (<NUM>),
the female locking buckle (<NUM>) comprises a housing (<NUM>), the housing (<NUM>) is fixed to an end of the fixed rod (<NUM>) by means of a screw, an inner cavity of the housing (<NUM>) is provided with a limiting mechanism for slidably limiting the lock block (<NUM>), and the bottom of the housing (<NUM>) is provided with a trigger mechanism (<NUM>) of the positioning block (<NUM>).