Stroller

A stroller (10) includes: a front leg (31); a middle leg (34) located rearward of the front leg; a rear leg (37) located rearward of the middle leg; a front-wheel holding mechanism (21) provided on the front leg; a middle-wheel holding mechanism (24) provided on the middle leg; and a rear-wheel holding mechanism (27) provided on the rear leg. The front-wheel holding mechanism is configured to rotatably and turnably hold a front wheel (22). The middle-wheel holding mechanism is configured to rotatably and unturnably hold a middle wheel (25). The rear-wheel holding mechanism is configured to rotatably and turnably hold a rear wheel (28).

CROSS REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2012-154831 filed on Jul. 10, 2012 and the prior Japanese Patent Application No. 2012-259873 filed on Nov. 28, 2012, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a stroller capable of letting babies ride thereon in such a manner that the babies are seated in a back and front direction.

2. Background Art

As disclosed in US2002-033588, strollers capable of transporting a plurality of babies are used. As such strollers, there are known strollers of the type in which babies are seated in the lateral direction, and a stroller of a type in which babies are seated in the back and front positions. In the stroller of either type, a caregiver of the babies steers the stroller from a rear side thereof, while grasping a handle disposed on a rear part of the stroller. Generally, when the stroller travels along a curved path, the stroller is turned about an axis of a rear wheel position in the back and front direction, so as to change a traveling direction (facing direction) of the stroller.

However, in the stroller of a type in which babies are seated in the back and front positions, i.e., in the tandem-type stroller, an overall length from the back to the front is longer. Thus, in the stroller of a type in which babies are seated in tandem, the center of gravity of the stroller transporting the babies is positioned largely forward of a turning center of the stroller about which the stroller is turned to change its traveling direction. On the other hand, the handle to which a force is applied by the steering person is positioned near to the turning center of the stroller about which the stroller is turned so as to change its traveling direction, in the back and front direction. Thus, when the stroller is turned, it is necessary for the steering person to apply a very large force to the handle, which makes the steering difficult.

BRIEF SUMMARY OF THE INVENTION

The present invention has been made in view of the above circumstances. The object of the present invention is to improve the steerability of a stroller in which a plurality of babies can be seated in the back and front positions.

A first stroller according to the present invention is a stroller including:

a front leg;

a middle leg located rearward of the front leg;

a rear leg located rearward of the middle leg;

a front-wheel holding mechanism provided on the front leg, the front-wheel holding mechanism being configured to rotatably and turnably hold a front wheel;

a middle-wheel holding mechanism provided on the middle leg, the middle-wheel holding mechanism being configured to rotatably and unturnably hold a middle wheel; and

a rear-wheel holding mechanism provided on the rear leg, the rear-wheel holding mechanism being configured to rotatably and turnably hold a rear wheel,

wherein the stroller is capable of letting babies ride thereon in such a manner that the babies are seated in a back to front position.

The first stroller according to the present invention may further include:

a handle;

a fourth link element pivotably joined, at a rear portion thereof, to the handle, and pivotably joined to an upper portion of the rear leg;

a first link element pivotably joined, at a rear portion thereof, to the handle, and pivotably joined, at a front portion thereof, to the front leg;

a second link element pivotably joined to a front portion of the fourth link element, and pivotably joined to an intermediate portion of the first link element;

a third link element pivotably joined, at a rear portion thereof, to the second link element, and pivotably joined to an upper portion of the front leg and an upper portion of the middle leg;

a fifth link element pivotably joined to the second link element and the middle leg, respectively; and

a sixth link element pivotably joined to the handle and the rear leg, respectively.

In the first stroller according to the present invention, a pair of the front legs may be provided to be spaced apart from each other in a width direction; a pair of the middle legs may be provided to be spaced apart from each other in the width direction; a pair of the rear legs may be provided to be spaced apart from each other in the width direction; the front-wheel holding mechanism may be provided on each front leg; the middle-wheel holding mechanism may be provided on each middle leg; and the rear-wheel holding mechanism may be provided on each rear leg. Alternatively, in the first stroller according to the present invention, the front leg may include a pair of front-leg extending parts located to be spaced apart from each other in a width direction, and a front-leg connection part connecting the pair of front-leg extending parts; a pair of the middle legs may be provided to be spaced apart from each other in the width direction; a pair of the rear legs may be provided to be spaced apart from each other in the width direction; the front-wheel holding mechanism may be provided on the front connection part; the middle-wheel holding mechanism may be provided on each middle leg; and the rear-wheel holding mechanism may be provided on each rear leg. Alternatively, in the first stroller according to the present invention, a pair of the front legs may be provided to be spaced apart from each other in a width direction; a pair of the middle legs may be provided to be spaced apart from each other in the width direction; the rear leg may include a pair of rear-leg extending parts located to be spaced apart from each other in the width direction, and a rear-leg connection part connecting the pair of rear-leg extending parts; the front-wheel holding mechanism may be provided on each front leg; the middle-wheel holding mechanism may be provided on each middle leg; and the rear-wheel holding mechanism may be provided on the rear-leg connection part. Alternatively, in the first stroller according to the present invention, the front leg may include a pair of front-leg extending parts located to be spaced apart from each other in a width direction, and a front-leg connection part connecting the pair of front-leg extending parts; a pair of the middle legs may be provided to be spaced apart from each other in the width direction; the rear leg may include a pair of rear-leg extending parts located to be spaced apart from each other in the width direction, and a rear-leg connection part connecting the pair of rear-leg extending parts; the front-wheel holding mechanism may be provided on the front-leg connection part; the middle-wheel holding mechanism may be provided on each middle leg; and the rear-wheel holding mechanism may be provided on the rear-leg connection part.

A second stroller according to the present invention is a stroller including:

a front leg;

a rear leg located rearward of the front leg;

a middle leg located rearward of the middle leg;

a first link element pivotably joined, at a front portion thereof, to the front leg;

a handle pivotably joined to a rear portion of the first link element;

a fourth link element pivotably joined, at a rear portion thereof, to the handle, and pivotably joined to an upper portion of the rear leg;

a second link element pivotably joined to a front portion of the fourth link element, and pivotably joined to an intermediate portion of the first link element;

a third link element pivotably joined, at a rear portion thereof, to the second link element, and pivotably joined to an upper portion of the front leg and an upper portion of the middle leg;

a fifth link element pivotably joined to the second link element and the middle leg, respectively; and

a sixth link element pivotably joined to the handle and the rear leg, respectively.

In the second stroller according to the present invention, a pair of the front legs may be provided to be spaced apart from each other in a width direction; a pair of the middle legs may be provided to be spaced apart from each other in the width direction; and a pair of the rear legs may be provided to be spaced apart from each other in the width direction. Alternatively, in the second stroller according to the present invention, the front leg may include a pair of front-leg extending parts located to be spaced apart from each other in a width direction, and a front-leg connection part connecting the pair of front-leg extending parts; a pair of the middle legs may be provided to be spaced apart from each other in the width direction; and a pair of the rear legs may be provided to be spaced apart from each other in the width direction. Alternatively, in the second stroller according to the present invention, a pair of the front legs may be provided to be spaced apart from each other in the width direction, a pair of the middle legs may be provided to be spaced apart from each other in the width direction, and the rear leg may include a pair of rear-leg extending parts located to be spaced apart from each other in the width direction, and a rear-leg connection part connecting the pair of rear-leg extending parts. Alternatively, in the second stroller according to the present invention, the front leg may include a pair of front-leg extending parts located to be spaced apart from each other in the width direction, and a front-leg connection part connecting the pair of front-leg extending parts, a pair of the middle legs may be provided to be spaced apart from each other in the width direction, and the rear leg may include a pair of rear-leg extending parts located to be spaced apart from each other in the width direction, and a rear-leg connection part connecting the pair of rear-leg extending parts.

The first or second stroller according to the present invention may further include a first seat unit for letting a baby ride thereon and a second seat unit for letting a baby ride thereon, wherein the second seat unit is supported by a position, of the first link element, located rearward of the position at which the first link element is joined to the second link element, and the first seat unit is supported by the first link element on a position that is forward of the second seat unit.

The first or second stroller according to the present invention may further include a first seat unit for letting a baby ride thereon and a second seat unit for letting a baby ride thereon, wherein the first seat unit is supported by the third link element, and the second seat unit is supported by the fourth link element.

The first or second stroller according to the present invention may further include a first seat unit for letting a baby ride thereon and a second seat unit for letting a baby ride thereon, wherein at least a portion of the first seat unit is located between the front leg and the middle leg, in the back and front direction of the stroller, and the second seat unit is located rearward of the first seat unit, and at least a portion of the second seat unit is located between the middle leg and the rear leg, in the back and front direction of the stroller.

The first or second stroller according to the present invention may further comprise a stand member attached to a lower portion of the handle, wherein the stroller in a folded condition can stand by itself with only the stand member and the rear wheel being grounded. According to such a stroller, a space required for storing the stroller can be made smaller. In addition, handling of the folded stroller can be significantly improved.

In the first or second stroller according to the present invention, the stand member may be swingably attached to the handle and is urged to be separated from the rear wheel. According to such a stroller, a space required for storing the stroller can be made further smaller.

The first or second stroller according to the present invention may further include a braking mechanism capable of restricting rotation of the middle wheel. According to such a stroller, rotation of the wheel of the stroller can be stably restricted, while the braking mechanism can be made smaller and simplified.

In the first or second stroller according to the present invention, a pair of the middle legs may be provided to be spaced apart from each other in the width direction; the middle-wheel holding mechanism may be provided on each middle leg; and there may be provided a braking mechanism capable of restricting rotation of the pair of middle wheels held on the middle-wheel holding mechanisms. According to such a stroller, rotation of the wheel of the stroller can be stably restricted, while the braking mechanisms can be made smaller and simplified.

In the first or second stroller according to the present invention, the braking mechanism may include: a cam member that is located on a position between the pair of middle-wheel holding mechanisms or a position between the pair of middle legs; and shaft members that are respectively disposed between the cam member and the one middle wheel and between the cam member and the other middle wheel; the cam member may be movable between a first position and a second position; when the cam member is moved from the first position to the second position, each shaft member may be moved outward in the width direction to be engaged with the corresponding middle wheel so as to restrict the rotation of the middle wheel; and when the cam member is moved from the second position to the first position, each shaft member may be moved inward in the width direction to release the engagement between the shaft member and the corresponding middle wheel so as to enable the rotation of the middle wheel. According to such a stroller, by operating the one cam member, rotation of each of the pair of middle wheels can be restricted. Namely, the rotation of the wheel can be more reliably restricted by the simple operation.

In the first or second stroller according to the present invention, the braking mechanism may further include: an operation member that is movable between a release position and a restriction position, when the operation member is moved from the release position to the restriction position, the operation member being held as it is on the restriction position; and a release member configured to release the operation member held on the restriction position; when the operation member is moved from the release position to the restriction position, the cam member may be moved from the first position to the second position; and when the operation member is moved from the restriction position to the release position, the cam member may be moved from the second position to the first position. According to such a stroller, the cam member disposed on a position between the pair of middle-wheel holding mechanisms or a position between the pair of middle legs can be remotely operated, whereby the operability of the braking mechanism can be significantly improved.

According to the first or second stroller according to the present invention, the braking mechanism may further include an operation member configured to operate the movement of the cam member from the first position to the second position; and the operation member may be supported on a rear connection member that is located on a position between the pair of rear legs or a position between the pair of rear-wheel holding mechanisms. According to such a stroller, the cam member disposed on a position between the pair of middle-wheel holding mechanisms or a position between the pair of middle legs can be operated from the rear side of the stroller.

In the first or second stroller according to the present invention, the braking mechanism may further include socket members respectively disposed between the cam member and the one shaft member and between the cam member and the other shaft member; each socket member may have a recess opening outward in the width direction; and an inner end of the shaft member in the width direction may be located in the recess of the socket member, and the shaft member is relatively movable in the width direction with respect to the socket member. According to such a stroller, the cam member can be operated without adjusting the rotational position of the middle wheel.

In the first or second stroller according to the present invention, the braking mechanism may further include a first urging member configured to urge the shaft member outward in the width direction, and a second urging member configured to urge the shaft member inward in the width direction.

According to the present invention, it is possible to improve the steerability of a stroller in which a plurality of babies can be seated in a back to front position.

DETAILED DESCRIPTION OF THE INVENTION

An embodiment of the present invention will be described herebelow with reference to the drawings.FIGS. 1 to 6are views for explaining an embodiment of a stroller according to the present invention.

FIGS. 1 to 3show a stroller10in one embodiment of the present invention. As shown inFIG. 1, the stroller10includes a stroller body15, a first seat unit66supported by the stroller body15, and a second seat unit68supported by the stroller body15. The first seat unit66and the second seat unit68are places on which babies are seated, and are arranged to be aligned back to front. Namely, the illustrated stroller10is constituted as a two-seater stroller of a tandem type. As well shown inFIG. 4, the stroller body15includes a frame part30having legs31,34and37and a handle40, and wheel holding mechanisms21,24and27provided on lower portions of the respective legs31,34and37.

In addition, as shown inFIGS. 2 and 3, the illustrated stroller10can be folded such that the legs31,34and37and the handle40are brought close to each other. Many constituent elements of the stroller body15are pivotably coupled to each other, in order that the stroller can be folded.

In this specification, the terms “front”, “rear”, “up”, “down”, “back to front direction”, “up and down direction” and “lateral direction” regarding the stroller10and the constituent elements of the stroller mean, unless otherwise specified, “front”, “rear”, “up”, “down”, “back to front direction” (or “back and front direction”), “up and down direction” and “lateral direction”, with respect to an operator who grasps the handle40to operate the stroller10in the unfolded condition, in particular, the foldable stroller10in the unfolded condition. More specifically, the “back to front direction” corresponds to a right and left direction on sheet planes ofFIGS. 1 and 4. Unless otherwise specified, the “front” is a side to which the operator who pushes the handle faces. The right side of the sheet planes ofFIGS. 1 and 4is the front. Meanwhile, the “up and down direction” is a direction perpendicular to the back and front direction, and is a direction perpendicular to the ground on which the stroller10rests. Thus, when the ground surface is a horizontal surface, the “up and down direction” represents a vertical direction. The “lateral direction” is also a width direction, and is a direction perpendicular both to the “back to front direction” and the “up and down direction”.

The stroller10is described in more detail below with reference toFIGS. 1 to 4. The stroller10as a whole has a substantially symmetrical structure about a central surface in the width direction, which extends along the back to front direction. As can be understood fromFIGS. 1 and 4, in the stroller10in this embodiment, the frame part30includes the pair of right and left front legs31, the pair of right and left middle legs34, the pair of right and left rear legs37, a pair of right and left first link elements41, a pair of right and left second link elements42, a pair of right and left third link elements43, a pair of right and left fourth link elements44, a pair of right and left fifth link elements45, a pair of right and left sixth link elements46, and the handle40. As can be well understood fromFIGS. 1 to 3, the handle40has a U-shape, and includes a pair of right and left handle extending parts40aand a handle connection part40bextending between the pair of handle extending parts40a.

As shown inFIG. 4, the first link element41is pivotably joined, at a rear portion thereof, in particular, a rear end of the rear portion in the illustrated example, to a lower portion of the corresponding handle extending part40aof the handle40, in particular, a lower end of the lower portion of the handle extending part40ain the illustrated example. In addition, the first link element41is pivotably joined, at a front portion thereof, in particular, a front end of the front portion in the illustrated example, to an intermediate portion of the corresponding front leg31. The second link element42is pivotably joined, at a lower portion thereof, in particular, a lower end of the lower portion in the illustrate example, to an intermediate portion of the corresponding first link element41.

In the stroller10shown inFIGS. 1 to 4, the fourth link44functions as an armrest for a baby seated on the second seat unit68. The fourth link element44is pivotably joined, at a rear portion thereof, in particular, a rear end of the rear portion in the illustrated example, to a lower portion or an intermediate portion of the corresponding handle extending part40aof the handle40. The position at which the fourth link element44is joined to the handle extending part40aof the handle40is located above the position at which the first link element41is joined to the handle extending part40a. In addition, the fourth link element44is pivotably joined, at a front portion thereof, in particular, a front end of the front portion in the illustrated example, to an upper portion of the corresponding second link element42, in particular, an upper end of the upper portion of the second link element42in the illustrated example.

In the stroller10shown inFIGS. 1 to 4, the third link element43functions as an armrest for a baby seated on the first seat unit66. The third link element43is pivotably joined, at a rear portion thereof, in particular a rear end of the rear portion in the illustrated example, to an intermediate portion or an upper portion of the corresponding second link element42. The position at which the third link element43is joined to the second link element42is located between the position at which the second link element42and the fourth link element44are joined, and the position at which the second link element42and the first link element41are joined, in the longitudinal direction of the second link element42.

The front leg31is pivotably joined, at an upper portion thereof, in particular, an upper end of the upper portion in the illustrated example, to a front portion of the corresponding third link element42, in particular, a front end of the front portion of the third link element43in the illustrated example. The middle leg34is pivotably joined, at an upper portion thereof, in particular, an upper end of the upper portion in the illustrated example, to a front portion or an intermediate portion of the corresponding third link element43. The position at which the middle leg34is joined to the third link element43is located between the position at which the third link element43and the second link element42are joined, and the position at which the third link element43and the front leg31are joined, in the longitudinal direction of the third link element43.

The rear leg37is pivotably joined, at an upper portion thereof, in particular, an upper end of the upper portion in the illustrated example, to a front portion or an intermediate portion of the corresponding fourth link element44. The position at which the rear leg37is joined to the fourth link element44is located between the position at which the fourth link element44and the handle extending part40aof the handle40are joined, and the position at which the fourth link element44and the second link element42are joined, in the longitudinal direction of the fourth link element44.

In addition, the frame part30includes the left fifth link element45connecting the left middle leg34and the left second link element42, and the right fifth link element45connecting the right middle leg34and the right second link element42. Each fifth link45is pivotably joined, at one portion thereof, to an intermediate portion of the middle leg34, and is pivotably joined, at another portion thereof, to a lower portion or an intermediate portion of the second link element42. The position at which the fifth link element45is joined to the second link element42is located between the position at which the second link element42and the first link element41are joined, and the position at which the second link element42and the third link element43are joined, in the longitudinal direction of the second link element42. Namely, in the illustrated example, when the stroller10is viewed from the lateral side, a pivot axis line between the second link element42and the fifth link element45is displaced from both of a pivot axis line between the second link element42and the first link element41and a pivot axis line between the second link element42and the third link element43.

Further, the frame part30includes the left sixth link element46connecting the left rear leg37and the left handle extending part40aof the handle40, and the right sixth link element46connecting the right rear leg37and the right handle extending part40aof the handle40. Each sixth link element46is pivotably joined, at one portion thereof, to an intermediate portion of the rear leg37, and is pivotably joined, at another portion thereof, to a lower portion or an intermediate portion of the handle extending part40aof the handle40. The position at which the sixth link element46is joined to the handle extending part40aof the handle40is located between the position at which the handle extending part40aof the handle40and the first link element41are joined, and the position at which the handle extending part40aof the handle40and the fourth link element44are joined, in the longitudinal direction of the handle extending part40aof the handle40. Namely, in the illustrate example, when the stroller10is viewed from the lateral side, a pivot axis line between the handle40and the sixth link element46is displaced from both of a pivot axis line between the handle40and the first link element41and a pivot axis line between the handle40and the fourth link element44.

In addition, as shown inFIG. 1, there are provided, as members extending in the lateral direction (width direction) of the stroller10, a first footrest51connecting the pair of front legs31, a second footrest52connecting the pair of middle legs34, and a tray50connecting the pair of third link elements43. Although not shown, a first support member for supporting the first seat unit66and a second support member for supporting the second seat unit68are disposed between the pair of first link elements41. Further, as shownFIG. 13which is described below, there may be provided a middle connection member51extending between the pair of middle-wheel holding mechanisms24or between the pair of middle legs34, and a rear connection member52extending between the pair of rear-wheel holding mechanisms24or between the pair of rear legs37.

The stroller body15is constituted by providing the wheel holding mechanisms21,24and27holding wheels22,25and28to the frame part30as structured above. In the illustrated example, the wheel holding mechanisms21,24and27are fixed on lower ends of the corresponding legs31,34and37.

The front-wheel holding mechanism21provided on each front leg31is formed as a caster, and is configured to rotatably and turnably support the front wheel22. Thus, as well shown inFIG. 6, the front wheel22of the front-wheel holding mechanism21is rotatable about a rotating axis line Ar and is turnable about a turning axis line As which is not in parallel with the rotating axis line Ar. When the front wheel22is turned about the turning axis line As, the front wheel22is extended in a direction at an angle with respect to the back to the front direction of the stroller10, and the rotating axis line Ar of the front wheel22is extended in a direction at an angle with respect to the width direction of the stroller10. Similarly, the rear-wheel holding mechanism27provided on each rear leg37is formed as a caster, and is configured to rotatably and turnably support the rear wheel28. Thus, as well shown inFIG. 6, the rear wheel28of the rear-wheel holding mechanism27is rotatable about a rotating axis line Ar, and is turnable about a turning axis line As that is not in parallel with the rotating axis line Ar.

On the other hand, the middle-wheel holding mechanism24provided on each middle leg34is not formed as a caster. The middle-wheel holding mechanism24is configured to rotatably and unturnably support the middle wheel25. Thus, as well shown inFIG. 6, the middle wheel25of the middle-wheel holding mechanism24is rotatable about an rotating axis line Ar. Meanwhile, the rotating axis line Ar of the middle wheel25is maintained in a constant direction. In the illustrate example, the rotating axis line Ar of the middle wheel25is extended in parallel with the width direction of the stroller10.

The first seat unit66and the second seat unit68are mounted on the stroller body15as structured above. Preferably, the first seat unit66and the second seat unit68can be attached to and detached from the stroller body15. The stroller10described herein is constituted as a tandem-type stroller for letting babies ride thereon in such a manner that the babies are seated in the back and front. Thus, the first seat unit66and the second seat unit68are arranged to be aligned in the back and front direction.

In the example shown inFIG. 4, when the stroller10is viewed from the lateral side, at least a portion of the first seat unit66is located between the front leg31and the middle leg34, and at least a portion of the second seat unit68, which is positioned rearward of the first seat unit66, is located between the middle leg34and the rear leg37. To be more specific, the first seat unit66and the second seat unit68respectively include seat parts66aand68afor supporting buttocks of babies, and back parts66band68bfacing backs of the babies.

The seat parts66aand68aof the respective seat units66and68are mainly supported by the pair of first link elements41and the first and second support members (not shown) provided on the pair of first link elements41. As shown inFIG. 4, the seat part68aof the second seat unit68is supported by a portion of the first link element41, the portion being rearward of the position at which the first link element41is pivotably coupled to the second link element42. The back part68bof the second seat unit68is swingable with respect to the seat part68a. For example, a reclining adjustment belt fixed to the pair of handle extending parts40aof the handle40is disposed on a back side of the back part68bof the second seat unit68. By adjusting a length of the reclining adjustment belt, a reclining angle of the back part68bcan be adjusted.

On the other hand, the seat part66aof the first seat unit66is supported by a front portion of the first link element41, i.e., a portion of the first link element41, the portion being substantially forward of the position at which the first link element41is pivotably coupled to the second link element42. The back part66bof the first seat unit66is swingable with respect to the seat part66a. For example, a reclining adjustment belt fixed to the pair of second link elements42are disposed on a back side of the back part66bof the first seat unit66. By adjusting a length of the reclining adjustment belt, a reclining angle of the back part66bcan be adjusted.

FIG. 5shows a modification example of the first seat unit66and the second seat unit68. In the modification example shown inFIG. 5, the first seat unit66is detachably attached to the third link element43of the stroller body15. The second seat unit68, which is positioned rearward of the first seat unit66, is detachably attached to the fourth link element44of the stroller body15. In this example, at least one of the first seat unit66and the second seat unit68can be attached to the stroller body15, such that either a baby seated thereon faces forward (illustrated condition) and/or a baby seated thereon faces rearward.

As shown inFIG. 1, the stroller10further includes a front hood61, a rear hood62and a basket63, which are provided on the stroller body15. The front hood61is disposed correspondingly to the first seat unit66, and functions as a sun shade and a wind shade (protect from the wind) for a baby seated on the first seat unit66. The rear hood62is disposed correspondingly to the second seat unit68, and functions as a sun shad and a wind shade (protect from the wind) for a baby seated on the second seat unit68. The basket63is disposed below the second seat unit68. Illustration of the front hood61, the rear hood62and the basket63is omitted in the drawings other thanFIGS. 1 to 3.

The stroller10as structured above can be folded from the unfolded condition shown inFIG. 1to the folded condition shown inFIG. 3through the condition shown inFIG. 2. During the folding operation, the respective constituent elements forming the frame part30of the stroller body15are rotated (pivoted, swung) with each other about an axis line extending in the lateral direction.

The specific folding operation is as follows. Firstly, the handle40is once pulled up and then pushed down, so that the fourth link element44and the first link element41are rotated counterclockwise inFIGS. 1 and 2with respect to the handle extending part40aof the handle40. Due to this operation, when the stroller10is viewed from the lateral side, the second link element42and the handle extending part40aof the handle40are brought close to each other, in a substantially parallel relationship. In addition, the first link element41and the third link element43are rotated counterclockwise inFIGS. 1 and 2with respect to the second link element42. Due to this operation, when the stroller10is viewed from the lateral side, the second link element42and the front leg31are brought close to each other, in a substantially parallel relationship.

Further, during the folding operation, the middle leg34joined to the fifth link element45is rotated clockwise inFIGS. 1 and 2with respect to the third link element43. Similarly, the rear leg37joined to the sixth link element46is rotated clockwise inFIGS. 1 and 2with respect to the fourth link element44.

As shown inFIG. 3, as a result of the above folding operation, when the stroller10is viewed from the lateral side, the handle40, the rear leg37, the second ink element42, the middle leg34and the front leg31are close to each other in substantially parallel with each other, with the handle40being located on a lower position. In the above manner, the stroller10can be folded, so that dimensions of the stroller10can be reduced along the back and front direction of the stroller10and along the up and down direction thereof. On the other hand, in order to unfold the stroller10in the folded condition shown inFIG. 3to the unfolded condition shown inFIG. 1through the condition shown inFIG. 2, the above folding steps are reversely performed.

As described above, a conventional stroller for letting babies ride thereon in such a manner that the babies are seated in the back to front direction has a problem of significantly poor steerability, which is caused by the long overall length of the stroller in the back to front direction. Such a problem of the conventional stroller is described with reference toFIG. 7. A conventional stroller110schematically illustrated inFIG. 7includes a pair of front-wheel holding mechanisms121and a pair of rear-wheel holding mechanisms127. The pair of front-wheel holding mechanisms121are formed as casters, and are configured to rotatably and turnably hold front wheels122. The pair of rear-wheel holding mechanisms127are not formed as casters, and are configured to rotatably and unturnably hold rear wheels128.

When such a stroller110travels along a curved path, namely, when such a stroller110turns, as shown inFIG. 7, the stroller110is turned about a turning center TC located near to the rear wheels in the back and front direction, so as to change a traveling direction of the stroller110from the traveling direction indicated by the dotted line inFIG. 7to the traveling direction indicated by the solid line inFIG. 7, omitting a movement component in the back and front direction of the stroller110. At this time, a steering person of the stroller110grasps a handle connection part140bof a handle140and applies a force for changing the traveling direction of the stroller110along the width direction of the stroller110.

However, a distance along the back to front direction of the stroller from the handle140, to which the force for operation is added, to a turning center TC is short. On the other hand, the tandem-type stroller10has a large length in the back and front direction. Accordingly, a center position CP of a weight including a weight of the stroller itself and weights of babies seated on the stroller is distant away from the turning center TC along the back and front direction. In the first place, since a plurality of babies are placed on the tandem-type stroller110, a large force is required for steering the stroller110. As a result of the above, a larger force is required for turning the conventional stroller110, which significantly impairs the steerability of the stroller110.

In addition, as described above, since a large force is applied to the conventional stroller110, it is necessary to make rigid the structural components of the stroller110including the handle140. As a result, a total weight of the stroller110is increased, which further increases a force required for steering the stroller110, resulting in further degradation in steerability of the stroller110.

In order to eliminate such a problem, it can be considered that the length of the stroller110in the back to front direction is reduced. However, when the length of the stroller110in the back to front direction is reduced, livability or spaciousness in the stroller110is significantly degraded.

On the other hand, as described above, the stroller10in this embodiment further includes the middle legs34, in addition to the front legs31and the rear legs37. In addition, the stroller10includes the front-wheel holding mechanisms21provided on the front legs31, which are formed as casters, the middle-wheel holding mechanisms24provided on the middle legs34, which are not formed as casters, and the rear-wheel holding mechanisms27provided on the rear legs37, which are formed as casters. Thus, when the stroller10is turned, as shown inFIG. 6, the stroller10is turned about a turning center TC located near to the middle wheels in the back and front direction, so as to change a traveling direction (facing direction) of the stroller10from the traveling direction indicated by the dotted line inFIG. 6to the traveling direction indicated by the solid line inFIG. 6, omitting a movement component in the back and front direction of the stroller10.

Thus, the distance of the stroller10along the back to front direction, from the handle connection part40bof the handle40, to which a steering person of the stroller10applies a force for steering the stroller10, to the turning center TC can be elongated. Therefore, a force to be applied to the handle40for steering the stroller10can be significantly decreased. As a result, the steerability of the stroller10is significantly improved.

Furthermore, as shown inFIG. 4, when the stroller10is viewed from the front side, it is possible to locate the middle leg34and the middle-wheel holding mechanism24substantially between the first seat unit66and the second seat unit68. In this case, a center position CP of a weight including the weight of the stroller itself and weights of babies on the stroller10can be located near to the middle wheel25in the back to front direction of the stroller10. That is to say, as shown inFIG. 6, in the stroller10in this embodiment, the turning center TC about which the stroller10is turned so as to change a traveling direction of the stroller, and the center position CP of the weight of the stroller10can be located close to each other, and further the turning center TC and the center position CP can be at the same position in the back and front direction of the stroller10. Thus, according to this embodiment, a moment required for changing a traveling direction of the stroller10can be significantly lowered.

Accordingly, a force to be applied to the handle40by a steering person when the stroller10is turned can be significantly effectively reduced. Thus, the steerability of the stroller10is significantly effectively improved. In addition, since a large force is not applied to the respective constituent elements of the stroller10, the respective constituent elements can be simplified and reduced in weight. Thus, the steerability is further improved, as well as the manufacturing is the stroller10can be lowered. Furthermore, since it is not necessary to reduce the size of the stroller10, in particular, the overall length thereof along the back to front direction, with a view of improvement in steerability, degradation in livability or spaciousness of the stroller10as well as comfortableness of the stroller10is avoided.

Moreover, in this embodiment, the tandem-type stroller10having a long overall length in the back to front direction is provided with, in addition to the front legs31and the rear legs37, the middles legs34disposed between the front legs31and the rear legs37. Thus, weights of babies on the stroller10is supported in a well balanced manner. In conjunction therewith, also in the foldable-type stroller10in which the respective constituent elements of the stroller10are rotatable with each other, deformation such as deflection of the stroller10can be effectively restrained. Also from these points, the steerability of the stroller10is effectively enhanced.

The aforementioned embodiment can be variously modified. An example of the modification will be described below. In the following description and the following drawings used in the description, a component that can be constituted similarly to that of the aforementioned embodiment and other modification examples is shown by the same reference symbol used for the corresponding component of the aforementioned embodiment and other modification examples, and overlapping explanation is omitted.

For example, in the aforementioned embodiment, the two seat units, i.e., the first seat unit66and the second seat unit68are arranged in the back to front direction. However, not limited thereto, three or more seat units may be disposed on the stroller10. For example, three or more seat units may be arranged on the stroller10in the back to front direction. Alternatively, the stroller10may include two seat units, which are arranged in the width direction of the stroller10, and two seat units, which are arranged in the width direction of the stroller10and rearward of the former two seat units.

For example, the detailed structures of the stroller10as described above are nothing more than mere examples. For example, the aforementioned embodiment shows the example in which there are provided the pair of front legs31located to be spaced apart from each other in the width direction, the pair of middle legs34located to be spaced apart from each other in the width direction, the pair of rear legs located to be spaced apart from each other in the width direction, the pair of first link elements41located to be spaced apart from each other in the width direction, the pair of second link elements42located to be spaced apart from each other in the width direction, the pair of third link elements43located to be spaced apart from each other in the width direction, the pair of fourth link elements44located to be spaced apart from each other in the width direction, the pair of fifth link elements45located to be spaced apart from each other in the width direction, and the pair of sixth link elements46located to be spaced apart from each other in the width direction. In this example, the front leg31, the middle leg34, the rear leg37and the first to sixth link elements41to46, which are positioned on one side in the width direction (e.g., on the right side), are connected to each other so as to form a link structure for enabling the folding operation of the stroller body15. Similarly, the front leg31, the middle leg34, the rear leg37and the first to sixth link elements41to46, which are positioned on the other side in the width direction (e.g., on the left side) are connected to each other so as to form a link structure for enabling the folding operation of the stroller body15. The front-wheel holding mechanism22including the front wheel22is disposed on each of the pair of front legs31. The middle-wheel holding mechanism24including the middle wheel25is disposed on each of the pair of middle legs34. The rear-wheel holding mechanism27including the rear wheel28is disposed on each of the pair of rear legs37. However, not limited to this example, one of the pair of front legs31, the pair of middle legs34and the pair of rear legs37may be formed in a U-shape, and the only one front-wheel holding mechanism21, the only one middle-wheel holding mechanism24or the only one rear-wheel holding mechanism27may be provided.

As an example,FIG. 8shows that the front leg32includes a pair of front-leg extending parts32a, and a front-leg connection part32bconnecting the pair of front-leg extending parts32a. In the illustrated example, the front-leg connection part32extends between lower ends of the pair of front-leg extending parts32a. In particular, in the example shown inFIG. 8, the front leg32is integrally formed in a U-shape. Such a front leg may be manufactured by, for example, bending a pipe made of metal such as aluminum alloy. Similarly to the front leg31in the aforementioned embodiment, each front-leg extending part32ais joined to the first link element41and the third link element43. On the other hand, the front-wheel holding mechanism22including the front wheel21is not disposed on each front-leg extending part32abut disposed on the front-leg connection part32b. Namely, the stroller10shown inFIG. 8is a five-wheel stroller. Such a stroller10can provide the same effect as that of the aforementioned embodiment, as long as the front wheel22and the rear wheel28are rotatably and turnably held, while the middle wheel25is rotatably and unturnably held. Namely, it is possible to improve the steerability of a stroller capable of letting babies ride thereon in such a manner that the babies are seated in the back to front direction. By the same steps as those in the aforementioned embodiment, the stroller10can be folded, which is shown inFIG. 9, and the folded stroller10can be unfolded.

Further,FIG. 10shows an alternative example in which the rear leg38includes a pair of rear-leg extending parts38a, and a rear-leg connection part38bconnecting the pair of rear-leg extending parts38a. In the illustrated example, the rear-leg connection part38bextends between lower ends of the pair of rear-leg extending parts38a. In particular, in the example shown inFIG. 10, the rear leg38is integrally formed in a U-shape. Such a rear leg may be manufactured by, for example, bending a pipe made of metal such as aluminum alloy. Similarly to the rear leg37in the aforementioned embodiment, each rear-leg extending part38ais joined to the sixth link element46and the fourth link element44. On the other hand, the rear-wheel holding mechanism27including the rear wheel28is not disposed on each rear-leg extending part32abut disposed on the rear-leg connection part38b. Namely, the stroller10shown inFIG. 8is a five-wheel stroller. Such a stroller10can provide the same effect as that of the aforementioned embodiment, as long as the front wheel22and the rear wheel28are rotatably and turnably held, while the middle wheel25is rotatably and unturnably held. Namely, it is possible to improve the steerability of a stroller capable of letting babies ride thereon in such a manner that the babies are seated in the back to front direction. Following the same steps as those in the aforementioned embodiment, the stroller10can be folded, and the folded stroller10can be unfolded.

Further, not limited to the examples shown inFIGS. 8 to 10, the front leg may include a pair of front-leg extending parts and a front-leg connection part connecting the pair of front-leg extending parts, and the rear leg may include a pair of rear-leg extending parts and a rear-leg connection part connecting the pair of rear-leg extending parts. In this example, the front-wheel holding mechanism may be provided on the front-leg connection part, the middle-wheel holding mechanism may be provided on each middle leg, and the rear-wheel holding mechanism may be provided on the rear-leg connection part. On the other hand, the middle leg may be formed in a U-shape and the only one middle-wheel holding mechanism24holding the middle wheel25may be provided. Also in this example, there can be provided the same effect as that of the aforementioned embodiment, as long as the front wheel22and the rear wheel28are rotatably and turnably held, while the middle wheel25is rotatably and unturnably held.

Further, in the aforementioned embodiment, there is described the example in which the stroller10is configured to be foldable. As shown inFIGS. 11 and 12, when the stroller10is foldable, the folded stroller10can preferably stand by itself. Similarly to the stroller in the aforementioned embodiment, the stroller10shown inFIGS. 11 and 12includes a front leg31, a middle leg34, a rear leg37, first to sixth link elements41to46, a front-wheel holding mechanism21, a middle-wheel holding mechanism24, a rear-wheel holding mechanism27, and a handle40. In addition, the front-wheel holding mechanism21and the rear-wheel holding mechanism27hold the wheels22and28rotatably and turnably, while the middle-wheel holding mechanism24holds the middle wheel25rotatably and unturnably. In addition, the stroller10shown inFIGS. 11 and 12further includes a stand member48attached to lower portion of the handle40, in particular, in the illustrated example, lower ends of the handle40. The stand member48shown inFIGS. 11 and 12includes a pair of stand extending parts48arespectively extending from the lower portions of the pair of handle extending parts40aof the handle40, and a stand connection part48bconnecting the pair of stand extending parts48a. The stand member48is formed in a substantially U-shape. As shown inFIG. 12, the folded stroller10can stand by itself, with only the pair of rear wheels28and the stand connection part48bof the stand member48being grounded.

In the example shown inFIGS. 11 and 12, the stand member48is preferably swingable with respect to the handle40. Otherwise, the stand member48projects when the stand member48is not used to enlarge the size of the stroller10. Thus, such a structure prevents enlargement of the stroller10in size. In the example shown inFIGS. 11 and 12, the stand member48is swingably attached to the handle40. When no external force is applied, the stand member48is urged to be separated from the rear wheel28with respect to the handle40, such that the illustrated stroller10can stand by itself. On the other hand, the stand member48can be swung to come close to the rear wheel28against the urging force. For example, when the folded stroller10shown inFIG. 12is placed in flat such that the handle40is directed downward, the stand member48is swung with respect to the stroller body15by a self weight of the stroller10so as to come close to the rear wheel28. Thus, the thickness of the folded stroller10can be reduced to achieve small folded dimensions.

Although not specifically mentioned in the aforementioned embodiment, the stroller10may include a braking mechanism that restricts rotation of the wheel. In this case, the braking mechanism is preferably configured to restrict the rotation of the middle wheel that is unturnably held. In this case, the braking mechanism can be made smaller and simplified. The rotation of the middle wheel can be more reliably restricted by the small and simple braking mechanism, whereby the stroller10can be stably maintained at rest. Herebelow, referring mainly toFIGS. 13 to 19, there is described an example in which the stroller10includes a braking mechanism70capable of restricting rotation of a middle wheel71.

FIG. 13shows lower portions of the middle legs34and the rear legs37. As shown inFIG. 13, the pair of middle legs34are provided, and the middle-wheel holding mechanisms95are attached to the lower ends of the respective middle legs34. The middle connection member51is provided between the pair of middle-wheel holding mechanisms95, and the pair of middle-wheel holding mechanisms95are connected to each other by the middle connection member51. In addition, the rear connection member52is provided between the pair of rear legs37, and the pair of rear legs37are connected to each other by the rear connection member52. The rear-wheel holding mechanisms27are attached to the lower ends of the respective rear legs37.

The middle-wheel holding mechanism95attached to the middle connection member51supports the middle wheel96so as to be rotatable about an axis (longitudinal center line) of the middle connection member51extending in the width direction. The middle wheel96includes a wheel98rotatably supported on the middle connection member51and a tire97mounted on the wheel98. In an inner surface of the wheel98, a plurality of locking recesses99are formed to be spaced apart from each other along a circumference about a rotational axis of the middle wheel96. The illustrated braking mechanism70includes shaft members81that are supported movably in the width direction with respect to the middle connection member by outer casings90attached to the middle connection member51and an inner casing93attached the middle connection member51. When an outer end81bof the shaft member81gets into the locking recess99of the middle wheel96, the rotation of the middle-wheel holding mechanism95is restricted. Respective structures of the braking mechanism70are described herebelow.

As shown inFIG. 14, the braking mechanism70includes a cam member74which is disposed on a position between the pair of middle-wheel holding mechanisms95or a position between the pair of middle legs34, the shaft members81respectively disposed between the cam member74and the one middle wheel96and between the cam member74and the other middle wheel96, and socket members77respectively disposed between the cam member71and the one shaft member81and between the cam member71and the other shaft member81. As described above, the respective shaft members81are supported between the respective outer casings90and the inner casing93. On the other hand, the cam member74and the pair of socket members77are supported by the inner casing93. The inner casing93is fixed on a central portion of the middle connection member51in the width direction. The outer casings90are respectively fixed on outer end portions of the middle connection member51in the width direction. Each of the outer casings90is opposed to the wheel98of the middle wheel96from inside in the width direction. The outer casing90has an outer opening91on a position opposed to the locking recess99of the middle wheel96. The outer end81bof the shaft member81is engaged with the middle wheel96through the outer opening91.

The cam member74can be moved between a first position shown inFIG. 15and a second position shown inFIG. 16. In the examples shown inFIGS. 15 and 16, by being rotated about an axial direction of the middle connection member51, the cam member74is movable between the first position and the second position. In a pair of side surfaces facing outward in the width direction, the cam member74has a receiving recess75formed along a part of a circumference about a rotational axis thereof. A bottom surface of the receiving recess75forms a cam surface75awhich varies a position in the width direction. As shown inFIGS. 15 and 16, a central urging member84formed of, e.g., a compression spring, is disposed in the inner casing93. The central urging member84urges the cam member74from the second position to the first position.

The socket member77is formed as an elongate member extending in the axial direction of the middle connection member51. An inner end77aof each socket member77, which is an inner end portion in the width direction, is placed in the receiving recess75of the cam member74and is in contact with the cam surface75a. On the other hand, an outer recess78opening outward in the width direction is formed in an outer end of each socket member77. An inner end81ain the width direction of the shaft member81is located in the outer recess78of the socket member77.

In addition, the braking mechanism70further includes a first urging member85that urges the shaft member81outward in the width direction, and a second urging member86that urges the shaft member81inward in the width direction. The first urging member85is formed of, e.g., a compression spring, and is arranged between the outer recess78of the socket member77and the inner end81aof the shaft member81. The second urging member86is formed of, e.g., a compression spring, and is arranged between an outer flange82of each shaft member81and a stepped part92formed around the outer opening91of the outer casing90, such that the outer end81bof each shaft member81passes through the second urging member86.

Along with the movement of the cam member74between the first position and the second position, the socket member77is moved in the width direction. In the illustrated example, when the cam member74is located on the first position ofFIG. 15, the socket member77is located relatively inside in the width direction, as shown inFIG. 17. On the other hand, when the cam member74is located on the second position ofFIG. 16, the socket member77is located relatively outside in the width direction, as shown inFIGS. 18 and 19.

The shaft member81can be relatively moved in the width direction with respect to the socket member77. In the illustrated example, in order to restrict a range where the shaft member81can be relatively moved with respect to the socket member77, a pin83is disposed on the shaft member81, and a side opening79is formed in a sidewall of the outer recess78of the socket member77. The side opening79extends in the width direction and is configured to be engaged with the pin83. Due to the engagement between the side opening79and the pin83, the relative movement of the shaft member81with respect to the socket member77is guided, and the range where the shaft member81can be relatively moved is defined.

As shown inFIGS. 13 to 16, the braking mechanism70further includes an operation member71that operates the movement of the cam member74from the first position to the second position. As shown inFIGS. 13 to 16, a transmission means88formed of, e.g., a wire is provided between the operation member71and the cam member74. A motion of the operation member71is transmitted to the cam member74through the transmission means88. The operation member71is supported on the rear connection member52that is located on a position between the pair of rear legs37or a position between the pair of rear-wheel holding mechanisms27. The operation member71can be moved between a release position and a restriction position. When the operation member71is moved from the release position to the restriction position, the cam member74is moved from the first position to the second position. On the other hand, when the operation member71is moved from the restriction position to the release position, the cam member74is moved from the second position to the first position. In this example, when the operation member71is moved from the release position to the restriction position, the operation member71is held as it is on the restriction position. The braking mechanism70further includes a release member that releases the operation member71held on the restriction position. The release member72is supported on the rear connection member52that is located on a position between the pair of rear legs37or a position between the pair of rear-wheel holding mechanisms27, and is positioned in the vicinity of the operation member71. In the illustrated example, both of the operation member71and the release member72are constructed as rotatable levers.

Next, the operation of the braking mechanism70as structured above is described. In a condition where the rotation of the middle wheel96is not restricted, the operation member71is located on the release position shown inFIG. 15, and the cam member74is located on the first position shown inFIG. 15. Simultaneously, the socket member77and the shaft member81are located on the positions shown inFIG. 17. Namely, the socket member77is located inside in the width direction. At this time, the first urging member85, which is formed of, e.g., a compression spring, is stretched out and does not actively press the shaft member81outward in the width direction. On the other hand, the second urging member86, which is formed of, e.g., a compression spring having an elastic coefficient lower than that of the first urging member85so as to be easily deformable, is somewhat compressed or stretched out, so that the outer end81bof the shaft member81is held on a position where the outer end81bdoes not project outward in the width direction from the outer opening91of the outer casing90.

In order to restrict the rotation of the middle wheel96, the operation member71is moved from the release position shown inFIG. 15to the restriction position shown inFIG. 16, so that the cam member74is rotated from the first position to the second position. As shown inFIG. 18, along with the rotation of the cam member74, the socket member77engaged with the cam surface75aof the cam member74is moved outward in the width direction. At this time, along with the movement of the socket member77, the first urging member85formed of a compression sprig having a higher elastic coefficient presses the shaft member81outward in the width direction. Note that, depending on a relationship between the position of the outer opening91of the outer casing90and the position of the locking recess99of the middle wheel96, the shaft member81cannot be always moved outward in the width direction. In the condition shown inFIG. 18, the outer opening91of the outer casing90is closed by the wheel98of the middle wheel96from outside in the width direction, and the outer end81bof the shaft member81does not project outward in the width direction from the outer casing90. Thus, in the condition shown inFIG. 18, along with the outward movement of the socket member77in the width direction, the first urging member85is compressed in the outer recess78of the socket member77so as to press the shaft member81outward in the width direction.

When the middle wheel96is somewhat rotated from the condition ofFIG. 18, the locking recess99of the middle wheel96is located on a position opposed to the outer opening91of the outer casing90. At this time, as shown inFIG. 19, the shaft member81pressed by the first urging member85is moved outward in the width direction through the outer opening91of the outer casing90into the locking recess99of the middle wheel96. When the shaft member81and the locking recess99have been engaged with each other, the rotation of the middle wheel96is restricted. In the condition shown inFIG. 19, both of the first urging member85and the second urging member86are somewhat compressed, and the force of the first urging member85which presses the shaft member81outward in the width direction and the force of the second urging member86which presses the shaft member81inward in the width direction remain in equilibrium.

In the manner as described above, the rotation of the pair of middle wheels96can be restricted. In order to release the restriction of rotation of the middle wheels96, the release member72is operated to return the operation member71from the restriction position to the release position. When the operation member71is moved from the restriction position to the release position, the cam member74is moved from the second position to the first position, so that the socket member77and the shaft member81are moved inward in the width direction. As a result, the engagement between the shaft member81and the middle wheel96is released, whereby the middle wheel96becomes rotatable.

Although some modification examples of the above embodiment are described, it is naturally possible to suitably combine the plurality of modification examples.