阅读说明：本技术 婴儿车 (Baby carriage ) 是由 柳尚辰 于 2019-04-12 设计创作，主要内容包括：本发明涉及一种婴儿车,提供由自行车结构体构成的婴儿车,包括：座椅部,其包括座椅和收容所述座椅的座椅收容部；连接框架部,其包括第一连接框架和第二连接框架,所述第一连接框架在两侧支撑座椅,包括竖向部分和横向部分,所述第二连接框架为通过竖向部分和横向部分形成的“U”字形状,所述竖向部分相对所述第一框架可旋转地连接；主框架,所述第一连接框架与前侧端部结合的同时,所述第二连接框架与后侧端部结合,从而安装所述连接框架部,并设置车座；前轮,其设置于所述主框架的前方下部；后轮,其设置于所述主框架的后方下部。(The invention relates to a baby carriage, which is composed of a bicycle structure body and comprises: a seat portion including a seat and a seat housing portion housing the seat; a connection frame portion including a first connection frame supporting the seat at both sides, including a vertical portion and a lateral portion, and a second connection frame having a "U" shape formed by the vertical portion and the lateral portion, the vertical portion being rotatably connected with respect to the first frame; a main frame to which the connection frame part is attached by coupling the first connection frame to the front end part and coupling the second connection frame to the rear end part, and a seat is provided; a front wheel arranged at the front lower part of the main frame; and the rear wheel is arranged at the lower rear part of the main frame.)

1. A stroller, comprising a bicycle structure, comprising:

a seat portion including a seat and a seat housing portion housing the seat;

a connection frame portion including a first connection frame supporting the seat at both sides, including a vertical portion and a lateral portion, and a second connection frame having a "U" shape formed by the vertical portion and the lateral portion, the vertical portion being rotatably connected with respect to the first connection frame;

a main frame to which the connection frame part is attached by coupling the first connection frame to a front end and coupling the second connection frame to a rear end, and on which a seat can be installed;

a front wheel arranged at the front lower part of the main frame; and

and the rear wheel is arranged at the lower rear part of the main frame.

2. The stroller according to claim 1,

the seat is characterized in that protruding portions extending downwards are arranged on two sides of the seat accommodating portion, fixing portions are arranged on vertical portions of the first connecting frame corresponding to the protruding portions, the fixing portions are provided with fixing grooves for the protruding portions to be inserted into, and therefore the seat accommodating portion is detachably formed on the connecting frame portion.

3. The stroller according to claim 1,

the front wheel is arranged at the front lower part of the main frame and can rotate and move while being capable of steering through a supporting fork supporting a front wheel shaft,

the rear wheels are disposed at the rear lower portion of the main frame and are rotatably and movably formed by combining one ends of a pair of rear wheel connection frames supporting rear wheel shafts, respectively, with a pair of fixed frames connected with the main frame.

4. The stroller according to claim 3,

one end of the fixed frame is rotatably connected with the main frame through a hinge,

the other end extends downwards from the left side and the right side relative to the main frame, so that the other end can be fixed at one end of a rear wheel connecting frame at a corresponding position, the fixed frame and the rear wheel connecting frame are combined with each other, and a fixed shaft is connected between the common shafts.

5. The stroller according to claim 4,

the main frame is provided with a combination device, and the combination device comprises:

a hollow joint part which is vertically fixed on the fixed shaft and is detachably jointed with the rear end part of the main frame; and

a fixing rod inserted into the hollow of the combining part to have an additional handle part fixing the second connection frame.

6. The stroller according to claim 5,

the joint, including:

a shape combination body which is arranged at the rear side end part of the main frame; and

and a detaching part integrally formed at an upper end of the combining part and combined with or separated from the combined body by rotation of the fixing shaft.

7. The stroller according to claim 6,

the joint is formed by inserting more than 2 tubes with different sizes into the tight connection mode in sequence, so that the length can be adjusted.

8. The stroller according to claim 1,

a coupling member rotatably coupled to a front side end portion of a main frame of the bicycle structure is provided at a lateral portion located at a lower end of the first connection frame,

a through hole portion is provided in a lateral portion of the second connection frame, and the fixing lever is inserted into the through hole portion at a rear end portion of the main frame of the bicycle structure and fixed to the coupling portion.

9. The stroller according to claim 8,

the coupling member has a hollow pipe shape rotatably provided at a lateral portion of the first connection frame, and a protrusion portion is integrally formed at one side, and is inserted into and fixed to a groove portion formed at a front side end portion of the main frame.

10. The stroller according to claim 1,

the bicycle structure constitutes tricycle, includes:

a front wheel which is arranged at the front lower part of the main frame and can be rotated and moved at the same time of being turned by a supporting fork for supporting a front wheel shaft; and

and a pair of rear wheels provided at a rear lower portion of the main frame and rotatably and movably formed by coupling one ends of a pair of rear wheel connection frames supporting rear wheel shafts, respectively, with a pair of fixed frames connected to the main frame.

11. The stroller of claim 10,

provided with a joining device comprising: a hollow coupling part which is detachably coupled to a rear side end of the main frame while being vertically fixed to a fixing shaft formed between shafts which the fixing frame and the rear wheel coupling frame are coupled to each other and are common; a fixing rod inserted into the hollow of the combining part to have an additional handle part fixing the second connection frame.

12. The stroller according to claim 1,

the bicycle structure constitutes two rounds of bicycles, includes:

a front wheel which is arranged at the front lower part of the main frame and can be rotated and moved at the same time of being turned by a supporting fork for supporting a front wheel shaft; and

and rear wheels provided at a rear lower portion of the main frame, having one end rotatably connected to the main frame by a hinge and the other end rotatably connected to the main frame between fixing frames extended downward from left and right sides, the rear wheels being supported in parallel on the left and right sides by rear wheel fixing frames which are cross-coupled, respectively, and being rotatably movable.

Technical Field

The present invention relates to a stroller, and more particularly, to a stroller in which a connection frame portion of a seat portion is coupled to or separated from a front side and a rear side of a main frame of a bicycle structure, and the stroller can be changed to a stroller or a bicycle as needed.

Background

Generally, the age of use of a stroller ranges from an infant to about 3 years old.

However, it is realistic that the purchase price of the stroller is very expensive compared to such a short usage time. In particular, in the case of a child who grows fast, the usage time becomes shorter due to the fast growth, and the stroller is often thrown away without any use.

In addition, recently, the number of children per family is less than one on average, and it is rare that such expensive strollers are handed over and used among brothers, and they are actually thrown away.

However, the conventional stroller is made foldable for easy storage, and only the functional parts of the stroller have been improved by changing the design.

In addition, consumers tend to purchase cheaper strollers and use them more often than they pay a high fee for a stroller that has been used for such a short period of time, and the consumers are actually neglecting the safety of strollers and considering the fee first.

Further, as the usage time of the stroller becomes shorter, it is not discarded due to malfunction of the stroller, etc., and most of the cases are thrown away due to the age of the stroller exceeding that of children even though it is almost the same as a new stroller, so that there is a problem in that the stroller not used due to such throwing away causes a serious waste of resources and environmental pollution.

Prior art documents

Patent document

(patent document 1) laid-open patent publication No. 2009-0129335 (2009.12.16)

Disclosure of Invention

Accordingly, the present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a stroller in which a connection frame portion to which a seat portion is coupled to or separated from a front side and a rear side of a main frame of a bicycle structure, and the stroller can be changed to a stroller or a bicycle as necessary.

Another object of the present invention is to provide a stroller in which a bicycle structure can be changed to a two-wheeled bicycle or a three-wheeled bicycle as needed.

In order to achieve the above object, the present invention provides a stroller including a bicycle structure, comprising: a seat portion including a seat and a seat housing portion housing the seat; a connection frame portion including a first connection frame supporting the seat at both sides, including a vertical portion and a lateral portion, and a second connection frame having a "U" shape formed by the vertical portion and the lateral portion, the vertical portion being rotatably connected with respect to the first connection frame; a main frame to which the connection frame part is attached by coupling the first connection frame to a front end and coupling the second connection frame to a rear end, and on which a seat can be installed; a front wheel arranged at the front lower part of the main frame; and the rear wheel is arranged at the lower rear part of the main frame.

According to an embodiment of the present invention, the seat receiving portion may be provided at both sides thereof with protrusions extended downward, and a fixing portion having a fixing groove into which the protrusion is inserted may be provided at a vertical portion of the first coupling frame corresponding to the protrusions, and the seat receiving portion may be detachably formed at the coupling frame portion.

According to an embodiment of the present invention, the front wheel is provided at a front lower portion of the main frame, and is rotatably and movably formed while being steerable by a support fork supporting a front wheel shaft, and the rear wheel is provided at a rear lower portion of the main frame, and is rotatably and movably formed by a combination of one end of a pair of rear wheel connection frames supporting a rear wheel shaft, respectively, and a pair of fixed frames connected to the main frame.

According to an embodiment of the present invention, one end of the fixed frame is rotatably connected to the main frame by a hinge, and the other end of the fixed frame is extended downward from both left and right sides with respect to the main frame, so that one end of the rear wheel connecting frame fixed to a corresponding position is secured, the fixed frame and the rear wheel connecting frame are coupled to each other, and a fixed shaft is coupled between the common shafts.

According to an embodiment of the present invention, a coupling device is provided at the main frame, the coupling device including: a hollow joint part which is vertically fixed on the fixed shaft and is detachably jointed with the rear end part of the main frame; a fixing rod inserted into the hollow of the combining part to have an additional handle part fixing the second connection frame.

According to an embodiment of the invention, the joint comprises:a shape combination body which is arranged at the rear side end part of the main frame; and a detaching part integrally formed at an upper end of the combining part and combined with or separated from the combined body by rotation of the fixing shaft.

According to an embodiment of the present invention, the coupling part is constructed in a form that 2 or more tubes having different sizes are sequentially inserted into tight connection so that the length can be adjusted.

According to an embodiment of the present invention, a coupling member rotatably coupled to a front side end portion of the main frame of the bicycle structure is provided at a lateral portion located at a lower end of the first connection frame, a through hole portion is provided at a lateral portion of the second connection frame, and the fixing lever is inserted into the through hole portion at a rear side end portion of the main frame of the bicycle structure and fixed to the coupling portion.

According to an embodiment of the present invention, the coupling member is in the shape of a hollow tube rotatably provided at a lateral portion of the first connection frame, and a protrusion portion is integrally formed at one side, and is inserted and fixed to a groove portion formed at a front side end portion of the main frame.

According to an embodiment of the present invention, the bicycle structural body constitutes a three-wheeled bicycle including: a front wheel which is arranged at the front lower part of the main frame and can be rotated and moved at the same time of being turned by a supporting fork for supporting a front wheel shaft; and a pair of rear wheels provided at a rear lower portion of the main frame and rotatably and movably formed by coupling one ends of a pair of rear wheel connection frames supporting rear wheel shafts, respectively, with a pair of fixed frames connected to the main frame.

According to an embodiment of the invention, a joining device is provided, comprising: a hollow coupling part which is detachably coupled to a rear side end of the main frame while being perpendicularly fixed to a fixing shaft formed between shafts which the fixing frame and the rear wheel coupling frame are coupled to each other and are common; a fixing rod inserted into the hollow of the combining part to have an additional handle part fixing the second connection frame.

According to an embodiment of the present invention, the bicycle structural body constitutes a two-wheeled bicycle including: a front wheel which is arranged at the front lower part of the main frame and can be rotated and moved at the same time of being turned by a supporting fork for supporting a front wheel shaft; and rear wheels which are provided at the rear lower part of the main frame, one ends of which are rotatably connected to the main frame by hinges, and the other ends of which are supported in parallel at the left and right sides by rear wheel holders which are cross-coupled, respectively, between fixed frames which extend downward from the left and right sides with respect to the main frame, and which are rotatably movable.

According to the stroller of the present invention configured as described above, the connection frame portion to which the seat portion is coupled to or separated from the front side and the rear side of the main frame of the bicycle structure, and the stroller can be changed to a stroller or a bicycle for use as needed, thereby achieving convenience in use.

In particular, the effect is that when the child using the stroller grows and needs the bicycle, the child can be changed to a tricycle or a two-wheeled bicycle without throwing away the stroller, thereby saving resources and reducing environmental pollution.

Drawings

Fig. 1 is a perspective view illustrating a stroller according to the present invention.

Fig. 2 is a front view showing a stroller according to the present invention.

FIG. 3 is an exploded perspective view illustrating a seat portion, connecting frame portion and bicycle structure in accordance with the present invention.

Fig. 4 is a perspective view showing a coupling structure of a second connecting frame portions and a rear side end portion of a bicycle structural body according to the present invention.

Fig. 5 is a perspective view showing a coupling structure of a first connecting frame of the connecting frame portion and a front side end portion of the bicycle structural body according to the present invention.

Fig. 6 is a front view showing a bicycle structure of a stroller according to the present invention.

Fig. 7 is a view of the seat portion of the stroller according to the present invention, which is disposed rearward from the front.

Fig. 8 is a front view showing a folded state of the stroller according to the present invention.

Fig. 9 is a perspective view showing a tricycle bicycle according to the present invention.

Fig. 10 is a perspective view showing a two-wheeled bicycle according to the present invention.

Description of the reference symbols

100: seat portion 110: chair (Ref. now to FIGS)

120: sunshade portion 130: connecting frame part

131: first connecting frame 132: second connecting frame

133: connecting shaft 140: seat accommodating part

150: the pedal 160: joining member

170: the blocking member 180: storage box

200: the bicycle structural body 210: main frame

220: front wheels 221: front wheel axle

222: the support fork 230: rear wheel

231: rear wheel axle 232: rear wheel connecting frame

233: the fixing frame 234: fixed shaft

235: rear wheel fixing frame 250: combining device

251: the coupling portion 252: fixing rod

253: handle portion 254: combined body

255: detaching part

Detailed Description

The present invention may take many forms and modifications, and embodiments thereof will be described in detail herein. However, the present invention is not limited to the specific embodiments disclosed, and all modifications, equivalents, and alternatives falling within the spirit and technical scope of the present invention are to be understood. In the drawings, like reference numerals are used for like components.

The term is used only for the purpose of distinguishing one constituent element from other constituent elements. The terminology used in the description presented herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Singular references, if not explicitly stated differently in the context, also include plural references.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Fig. 1 of the accompanying drawings is a perspective view showing a stroller according to the present invention, and fig. 2 is a front view showing a stroller according to the present invention. Further, fig. 3 is an exploded perspective view illustrating a seat portion, a connecting frame portion, and a bicycle structural body according to the present invention, fig. 4 is a perspective view illustrating a coupling structure of a second connecting frame of the connecting frame portion and a rear side end portion of the bicycle structural body according to the present invention, and fig. 5 is a perspective view illustrating a coupling structure of a first connecting frame of the connecting frame portion and a front side end portion of the bicycle structural body according to the present invention.

Fig. 6 is a front view showing a bicycle structure of a stroller according to the present invention, fig. 7 is a view showing a seat portion of the stroller according to the present invention installed with a front surface facing rearward, and fig. 8 is a front view showing a folded state of the stroller according to the present invention.

As shown in fig. 1 and 2, the stroller according to the present invention includes a seat portion 100, a connecting frame portion 130, and a bicycle structural body 200.

Here, the seat portion 100 includes: a seat 110 of fabric material for carrying a child; a sunshade 120 detachably disposed on the seat 110 for shielding sunlight; a seat receiving portion 140 of a rigid plastics material that receives the seat 110.

Rotation portions 141 for adjusting the angle of the seat 110 are provided on both the left and right sides of the seat accommodating portion 140. Further, a pedal 150 fixed by a connecting rod 151 connected to the rotating portion 141 is provided. The pedal 150 is also adjustable in angle by the rotation portion 141.

An insertion hole 111 is provided on the front upper surface of the seat 110, and a handle 212 of a bicycle that an infant can hold is detachably provided.

The connecting frame portion 130 is connected to the bicycle structural body 200 so that the seat portion 100 can be stably mounted to the bicycle structural body 200.

The connection frame part 130 includes: a first connection frame 131 supporting the seat portion 100 at both sides, including a vertical portion 131a and a lateral portion 131 b; and a second connection frame 132 having a U-shape formed by a vertical portion 132a and a lateral portion 132b, the vertical portion 132a being connected to a rotatable connection shaft 133 provided at both sides of the first connection frame 131, the lateral portion 132b having a through hole portion 132c into which a fixing rod 252 of a coupling device 250, which will be described later, is inserted.

The connection frame portion 130 configured as above may be fixed to the bicycle structure 200 in a state of being coupled with the seat 110.

As shown in fig. 6, the bicycle structure 200 is a traveling tool that is basically a three-wheeled bicycle having three wheels, in which a handle 212 and pedals 213 are removed, and that is a structure that is disposed below the seat portion 100, supports the seat portion 100, and allows a stroller to be smoothly and freely changed in position.

The bicycle structure 200 has a front wheel 220 provided at a front lower portion of a main frame 210 having a seat 211, and two rear wheels 230 provided at a rear lower portion of the main frame 210.

The seat 211 provided on the main frame 210 is guided in a front-rear direction along a guide groove formed in a length direction of the main frame 210 and can be fixed at a specific set position by a fixing means (not shown).

In particular, it is preferable that the saddle 211 is located in front of the main frame 210 when used as a stroller and behind the main frame 210 when used as a bicycle. With this configuration, the seat 211 is not used during traveling as a stroller, and the risk of the seat being lost is reduced. Of course, the seat 211 may be separately stored.

The front wheel 220 is provided at a lower front portion of the main frame 210, and is rotatable while being steerable by a support fork 222 supporting a front wheel shaft 221.

The rear wheel 230 is disposed at a rear lower portion of the main frame 210, and rotatably moves by coupling one end of a pair of rear wheel coupling frames 232 respectively supporting a rear wheel shaft 231 with a pair of fixing frames 233 coupled to the main frame 210.

Here, one end of the fixing frame 233 is rotatably connected to the main frame 210 by a hinge 236, and the other end extends downward from both left and right sides of the main frame 210, so that one end of the rear wheel connecting frame 232 can be fixed at a corresponding position.

The fixed frame 233 extended to both sides of the main frame 210 and the rear wheel connecting frame 232 are coupled to each other, and a fixed shaft 234 is connected between the common shafts.

The fixing shaft 234 is coupled between the rear wheel coupling frame 232 and the fixing frame 233, thereby performing a function of improving a supporting performance of the rear wheel 230 with respect to the ground. In this way, the fixed frame 233 fixed to the main frame 210 and the rear wheel connecting frame 232 are coupled to each other in a state of sharing a shaft by the fixed shaft 234, thereby stably supporting the rear wheel 230 on the ground. At this time, the rear wheel coupling frame 232 disposed in a direction crossing the fixed frame 233 is partially restricted from rotating around the fixed shaft 234. That is, the rear wheel connecting frame 232 axially fixed to the rear wheel shaft 231 does not rotate upward about the fixed shaft 234 but only rotates downward. The folding performance of the stroller when folded can be improved while improving the support performance of the rear wheel 230 with respect to the ground.

As shown in fig. 4, the bicycle structure 200 is provided with a coupling device 250, and the coupling device 250 couples and fixes the connecting frame portion 130 to the rear end portion of the main frame 210.

The bonding apparatus 250 includes: a hollow coupling part 251 which is vertically fixed to the middle of the upper surface of the fixing shaft 234 and detachably coupled to the rear end of the main frame 210; and a fixing rod 252 inserted into the hollow of the combining part 251 to have an additional handle part 253 fixedly connected to the second connection frame 132 of the frame part 130.

When the combining part 251 is combined with the fixing rod 252, the combining part 251 is formed in a manner that more than 2 tubes with different sizes are inserted in sequence and tightly connected, so that the length can be adjusted as required.

In this way, the length of the coupling portion 251 is adjusted, and fixing means such as a groove and a protrusion are formed at the coupling portion 251 or the fixing bar 252 so that the length can be adjusted by selective coupling of the fixing means.

Further, the joint 251 is detachably configured from a rear side end portion of the main frame 210, and includes: a square coupling body 254 provided at a rear end of the main frame 210; and a detaching part 255 integrally formed at an upper end of the coupling part 251, coupled to or separated from the coupling body 254 by rotation of the fixing shaft 234.

The fixing rod 252 of the coupling device 250 is inserted into the through hole 132c of the lateral portion 132b of the second coupling frame 132 of the coupling frame part 130 and fixed to the hollow of the coupling part 251, and the coupling frame part 130 is fixed to the bicycle structure 200.

Therefore, the connecting frame portion 130 configured as above is fixed to the bicycle structure 200 in a state of being coupled with the seat 110.

As shown in fig. 3, a protrusion 142 extended downward is provided at the rotating portion 141 at both sides of the seat receiving portion 140, a fixing portion 143 is provided at a longitudinal portion 131a of the first coupling frame 131 corresponding to the protrusion, the fixing portion 143 has a fixing groove 143a into which the protrusion 142 is inserted, the protrusion 142 is inserted into the fixing groove 143a of the fixing portion 143, and the seat 110 is coupled to the coupling frame portion 130.

Further, as shown in fig. 5, a coupling member 160 coupled to a front side end portion of the main frame 210 of the bicycle structural body 200 is provided at a lateral portion 131b located at a lower end of the first coupling frame 131.

The coupling member 160 has a hollow pipe shape rotatably provided at a lateral portion of the first connection frame 131.

Further, a protrusion 161 is integrally formed at the coupling member 160 so as to be inserted and fixed into a groove portion 210a formed at a front side end portion of the main frame 210.

Accordingly, the protrusion 161 of the coupling member 160 provided to the first connection frame 131 is inserted into and coupled to the groove 210 formed at the front end of the main frame 210 of the bicycle structural body 200.

Meanwhile, as shown in fig. 4, in a state where the hollow of the coupling portion 251 is aligned with the through hole portion 132c of the second connection frame 132, the fixing rod 252 having the handle portion 253 is inserted into the through hole portion 132c and the coupling portion 251 in order and coupled.

Accordingly, the first and second connection frames 131 and 132 of the connection frame portion 130 are fixed to the front and rear end portions of the main frame 210 of the bicycle structural body 200, respectively, so that the seat portion 100 and the link frame portion 130 of the stroller are firmly fixed to the bicycle structural body 200.

Meanwhile, as shown in fig. 7, in the stroller including the seat portion 100, the connecting frame portion 130, and the bicycle structure 200, in a state in which the front surface of the seat 110 faces forward, the protruding portion 142 inserted into the fixing portion 143 of the first connecting frame 131 is separated to change the direction of the seat 110, and then the protruding portion 142 is inserted into the opposite fixing portion 143, so that the front surface direction of the seat 110 can be changed and the stroller can be disposed to face backward.

Fig. 8 is a view showing a folded state of the stroller according to the present invention, in which the seat 110 is first adjusted in angle to be parallel to the first coupling frame 131 of the coupling frame part 130 in a state where the sunshade 120 of the seat part 100 is folded.

Then, in a state where the detachable part 255 is separated and separated from the coupled body 254 of the coupling device 250, if the upper end part of the first coupling frame 131 is lifted up, the rear wheel coupling frame 232 rotates downward around the fixed shaft 234 of the bicycle component 200 and is positioned on the same line as the second coupling frame 132 together with the rear wheel 230.

Meanwhile, the connection shaft 133 rotates together with the second connection frame 132 in the folding direction with respect to the first connection frame 131, and the main frame 210 rotatably coupled to the coupling member 169 of the first connection frame 131 rotates while the entire stroller is folded.

The front wheel 220 and the rear wheel 230 together maintain a substantially fully folded condition with respect to each other.

In addition, the stroller is provided such that the connection frame portion 130 to which the seat portion 110 is attached can be separated from the stroller as needed, and thus the stroller can be easily changed to a bicycle, thereby facilitating the use.

When the baby using the baby carriage grows and needs the bicycle, the baby carriage is not thrown away and can be changed into a tricycle or a two-wheel bicycle for use, thereby saving resources and reducing environmental pollution.

Fig. 9 is a perspective view showing a three-wheeled bicycle according to the present invention, and fig. 10 is a perspective view showing a two-wheeled bicycle according to the present invention.

First, if the stroller is changed to a tricycle or the bicycle structure 200 is changed to a tricycle, the connection frame portion 130 to which the seat portion 110 is attached is separated from the stroller, and the state of the bicycle structure 200 is changed.

As shown in fig. 6, in order to change the bicycle structure 200 to the tricycle of fig. 9, the saddle 211 is installed and fixed to the rear side of the main frame 210.

An insertion hole 210b is formed through the upper front side of the main frame 210, a steering shaft 212a of a bicycle handlebar 212 is vertically inserted into the insertion hole 210b downward to be connected to a support fork 222, and the support fork 222 is coupled to a front wheel 220 at the lower portion of the main frame 210. At this time, the groove portion 210b formed at the front end of the main frame 210 is blocked by the blocking member 170.

A pedal 213 is provided on a front wheel shaft 221 of the front wheel 220, so that the front wheel 220 can be driven.

Further, a combining part 251 and a fixing lever 252 may be used separately from the bicycle structure 200, the combining part 251 being vertically formed on an upper surface of a fixing shaft 234 provided to the bicycle structure 200 and combined with a rear side end of the main frame 210, the fixing lever 252 having a handle 253 inserted into the combining part 251.

However, it is preferable that the child riding on the tricycle controls the running of the tricycle by holding the handle portion 253 in a state where the coupling portion 251 and the fixing lever 252 are provided and the coupling portion 251 is adjusted to be extended long when the child riding on the tricycle is under the protection of the protector.

Fig. 10 is a view showing a state in which the three-wheeled bicycle of fig. 9 is changed to a two-wheeled bicycle, and the two-wheeled bicycle can be used by changing a pair of rear wheels 230 disposed at lower portions of both sides of the main frame 210 to one rear wheel 230, separating the fixed shaft 234 fixed between the fixed frames 233, and cross-coupling one rear wheel shaft 231 and the rear wheel fixed frames 235 supported in parallel on both left and right sides between the fixed frames 233.

At the fixing frame 233 and the rear wheel fixing frame 235, at least one tight coupling hole (not shown) is provided which can be tightly coupled by a tight coupling means 233a of a fixing clip or the like.

Accordingly, after the tight coupling hole formed in the fixing frame 233 and the rear wheel fixing frame 235 are conformed to each other, the tight coupling means 233a is tightly coupled, so that one rear wheel 230 is stably supported on the ground.

Note that unexplained reference numeral 180 denotes a storage case selectively provided to the fixed shaft 234.

While the preferred embodiments of the present invention have been described above, it is to be understood that the present invention is not limited to the above-described embodiments, and various modifications and variations can be made by those having ordinary knowledge in the art to which the present invention pertains without departing from the scope of the claims of the present invention.