HK40052808B - Baby carriage - Google Patents

Description

stroller

This application is a divisional application of the original invention patent application No. 202080005998.8 (PCT application No.: PCT/JP2020/017225, application date: April 21, 2020, invention title: stroller).

Technical Field

The present invention relates to a stroller with a handle that can swing between a first position and a second position.

Background Technology

For example, as disclosed in Patent Document 1 (JP2017-81252A), strollers with a swingable handle are known. In the stroller disclosed in Patent Document 1, the handle can swing between a rear-push position and a front-push position. In the rear-push position, the handle is located on the back side of the infant, and the caregiver pushes the stroller from the back side to move the stroller forward. In the front-push position, the handle is located on the side facing the infant, and the caregiver pushes the stroller from the side facing the infant to move the stroller forward.

With the handle in the rear-facing position, the infant can face forward in the direction of travel. With the handle in the front-facing position, the caregiver can keep an eye on the infant while moving the stroller. Therefore, when placing young infants in a stroller, the handle is often positioned in the front-facing position, while when placing infants, for example, those who can sit up, the handle is often positioned in the rear-facing position.

As mentioned above, there is a tendency to change the handle position according to the infant's age. On the other hand, in previous strollers, there has been no research on changing the characteristics of the handle based on its position. For example, it would be preferable to improve the stroller's stability by arranging the handle in a face-pushing position that is more suitable for younger infants, while improving the stroller's maneuverability by arranging the handle in a rear-pushing position that is more suitable for older infants.

Summary of the Invention

The present invention was made with the above considerations in mind, and its purpose is to change the characteristics of a stroller according to the configuration of a swing handle.

The stroller of the present invention includes:

The main frame has front legs and hind legs;

A handle that is connected to the main frame in a manner that allows it to swing between a first position and a second position;

The first caster has a first fixed body fixed to the front leg, a first rotating body supported on the first fixed body in a manner rotatable about a first caster axis, and a single front wheel supported on the first rotating body in a rotatable manner; and

The second caster has a second fixed body fixed to the rear leg, a second rotating body supported on the second fixed body in a manner rotatable about the axis of the second caster, and a pair of rear wheels supported on the second rotating body in a rotatable manner.

When the handle is in the second position, the rotation of the first rotating body relative to the first fixed body is restricted, and when the handle is in the first position, the rotation of the second rotating body relative to the second fixed body is restricted.

In the stroller of the present invention, it may also be that...

The main framework has:

A first link is rotatably connected to the front leg and the hind leg;

The second link is rotatably connected to the first link;

The third link, which is rotatably connected to the front leg; and

The fourth link is rotatably connected to the hind leg.

The second link is rotatably connected to at least one of the third and fourth links.

The third link is rotatably connected to at least one of the fourth link and the second link.

The fourth link is rotatably connected to at least one of the second link and the third link.

In the stroller of the present invention, when viewed from the side, the connection position between the third link and the fourth link may be located behind the front leg.

In the stroller of the present invention, when viewed from the side, the connection position where the third link and the second link are connected is located behind the front leg.

In the stroller of the present invention, when viewed from the side, the connection position between the frame component and the base frame may be located further back than the front leg.

In the stroller of the present invention, it may also be that...

The main frame has a pair of front legs and a pair of rear legs that are separated in the width direction.

The first caster is provided on each of the pair of front legs.

The second caster is provided on each of the pair of hind legs.

The rear wheel of each second caster located on the outer side in the width direction is further outward than the front wheel of the first caster located on the same side in the width direction as the second caster.

In the stroller of the present invention, it may also be that...

The main frame has a pair of front legs and a pair of rear legs that are separated in the width direction.

The first caster is provided on each of the pair of front legs.

The second caster is provided on each of the pair of hind legs.

In the width direction, the front wheel of each first caster is located between the pair of rear wheels of the second caster that are on the same side of the first caster in the width direction.

In the stroller of the present invention, the front wheel of each first caster may be located at the center of the pair of rear wheels of the second caster that is on the same side as the first caster in the width direction.

In the stroller of the present invention, the distance between the pair of rear wheels may be greater than the width of the front wheels in the width direction.

In the stroller of the present invention, the distance between the pair of rear wheels in the width direction may also be greater than the width of the first fixing body.

In the stroller of the present invention, it may also be that...

The first rotating body has: a first rotating body base connected to the first fixed body in a manner rotatable about the axis of the first caster; and a first rotating body retainer connected to the first rotating body base and supporting the front wheel via an axle for rotation.

In the width direction, the spacing between the pair of rear wheels is greater than the width of the first rotating body base and greater than the width of the first rotating body cage.

In the stroller of the present invention, the stroller may also be foldable when the handle is configured in the first position.

In the stroller of the present invention, the diameter of the front wheel may be smaller than the diameter of the rear wheel.

In the stroller of the present invention, the width of the rear wheels may be narrower than the width of the front wheels.

In the stroller of the present invention, it may also be that...

The main frame has a pair of front legs and a pair of rear legs that are separated in the width direction.

The first caster is provided on each of the pair of front legs.

The second caster is provided on each of the pair of hind legs.

In the width direction, the first wheel axis of each first caster is located at the same position as the second wheel axis of the second caster that is on the same side of the first caster in the width direction.

In the stroller of the present invention, it may also be that...

The first rotating body includes: a first rotating body base connected to the first fixed body in a manner rotatable about the axis of the first caster; and a first rotating body retainer connected to the first rotating body base and supporting the front wheel via an axle for rotation.

The first rotating body base includes a first opposing surface facing the first fixed body from below.

In the width direction, the width of the first opposing surface is smaller than the width of the first rotating body cage, and the first opposing surface is located within the area of the first rotating body cage.

In the stroller of the present invention, it may also be that...

The first rotating body has a first opposing surface that faces the first fixed body from below.

The second rotating body has a second opposing surface that faces the second fixed body from below.

The height of the first opposing surface is higher than the height of the second opposing surface.

In the stroller of the present invention, it may also be that...

The first rotating body has a first opposing surface that faces the first fixed body from below.

The height of the first opposing surface is above the diameter of the front wheel.

In the stroller of the present invention, it may also be that...

The first rotating body has a first opposing surface that faces the first fixed body from below.

The height of the first opposing surface is above the diameter of the rear wheel.

In the stroller of the present invention, it may also be that...

The second rotating body has a second opposing surface that faces the second fixed body from below.

The height of the second opposing surface is less than the diameter of the front wheel.

In the stroller of the present invention, it may also be that...

The second rotating body has a second opposing surface that faces the second fixed body from below.

The height of the second opposing surface is less than the diameter of the rear wheel.

According to the present invention, the characteristics of a stroller can be changed according to the configuration of the swing handle.

Attached Figure Description

Figure 1 is a perspective view illustrating one embodiment of the present invention and explaining the overall structure of the stroller.

Figure 2 shows a side view of the stroller in Figure 1 with the handle in the first position (rear push position).

Figure 3 shows a side view of the stroller in Figure 1 with the handle in the second position (facing the push position).

Figure 4 shows a side view of the stroller in Figure 1 in a folded state.

Figure 5 is a perspective view showing a portion of the stroller in Figure 1.

Figure 6 is a front view showing a portion of the stroller in Figure 1.

Figure 7A is a schematic side view of the stroller of Figure 1 with the handle in the first position.

Figure 7B is a schematic side view of the stroller of Figure 1 with the handle in the second position.

Figure 8A is a schematic rear view of the stroller in Figure 1.

Figure 8B is a schematic front view of the stroller in Figure 1.

Detailed Implementation

Hereinafter, an embodiment of the present invention will be described with reference to a specific example shown in the accompanying drawings.

Figures 1 to 8B are diagrams illustrating one embodiment of the stroller of the present invention. Figures 1 to 4 show the overall structure of a specific example of the stroller. Figures 5 and 6 are perspective views or front views of the stroller, showing partial views. As shown in Figures 1 to 4, the stroller 10 of this embodiment includes: a main frame 12 having front legs 14 and rear legs 16; a handle 40 connected to the main frame 12 in a way that allows it to swing relative to the main frame 12; first casters 50 mounted on the front legs 14; and second casters 60 mounted on the rear legs 16. The main frame 12 and the handle 40 constitute the stroller body 11. Furthermore, as shown only in Figure 2 with double-dotted lines, a cushioned seat component 13 is detachably mounted to the stroller body 11. Infants sit or lie on this seat component 13.

In this embodiment, the handle 40 is swayable relative to the main frame 12 between a first position and a second position. In the illustrated example, the first position of the handle 40 is a rear-pushing position (see Figures 1 and 2), and the second position of the handle 40 is a facing-pushing position (see Figure 3). As shown in Figure 2, the handle 40 is tilted relative to the vertical direction and extends rearward in the first position, which is the rear-pushing position. When the handle 40 is positioned in the first position, which is the rear-pushing position, the operator (guardian) holds the handle 40 from the back of the infant to operate the stroller 10. At this time, the infant can enjoy the scenery facing forward in the direction of travel while the stroller 10 is moving. As shown in Figure 3, the handle 40 is tilted relative to the vertical direction and extends forward in the second position, which is the facing-pushing position. When the handle 40 is positioned in the second position, which is the facing-pushing position, the operator holds the handle 40 from the front leg side facing the infant to operate the stroller 10. At this time, the stroller 10 can be moved in such a way that the rear leg side of the stroller 10 faces forward in the direction of travel.

The illustrated stroller 10 (stroller body 11) is configured, as is widely used, to be foldable from the unfolded state shown in Figures 1 and 2 to the folded state shown in Figure 4. The stroller 10 (stroller body 11) can also be unfolded from the folded state to the unfolded state. When the stroller 10 is in the unfolded state, the handle 40 can be swung relative to the main frame 12.

Furthermore, in this specification, the terms "front," "rear," "up," "down," "front-rear direction," and "up-down direction" for strollers and their structural elements, unless otherwise specified, refer to the "front," "rear," "up," "down," "front-rear direction," and "up-down direction" based on the infant or toddler sitting in the stroller or its structural elements in their unfolded state. More specifically, "front-rear direction" is the direction connecting the lower left and upper right of the paper in Figure 1, corresponding to the left-right direction of the paper in Figures 2 and 3. Moreover, unless otherwise specified, "front" is the side that the infant or toddler facing, with the lower left side of the paper in Figure 1 and the left side of the paper in Figure 2 being the front side. On the other hand, "up-down direction" is the direction perpendicular to the travel surface of the stroller. Therefore, when the travel surface is horizontal, "up-down direction" refers to the vertical direction. Furthermore, "lateral" is the width direction, which is perpendicular to both the "front-rear direction" and the "up-down direction." As shown in Figure 1, the stroller 10 illustrated has a structure that is generally symmetrical about a surface located at the lateral center and centered on the front-rear and up-down directions.

First, the overall structure of the stroller will be described, specifically the stroller body 11. As described above, the stroller body 11 has a main frame 12 and a handle 40. As shown in Figure 1, the main frame 12 has a pair of front legs 14 and a pair of rear legs 16, each positioned on the left and right sides respectively. The main frame 12 also has a first link L1, a second link L2, a third link L3, and a fourth link L4, each positioned on the left and right sides respectively. The front legs 14, rear legs 16, and the first to fourth links L1 to L4 function as links that allow the stroller body 11 to be foldable and unfoldable. In the illustrated example, the first link L1 also functions as a handle 21. That is, the first link L1 is formed by the handle 21.

As shown in Figures 1 to 3, the upper part of the front leg 14 is rotatably (swingably) connected to the front part of the first link L1 located on the corresponding side (left or right). Similarly, the upper part of the rear leg 16 is rotatably (swingably) connected to the front part of the first link L1 located on the corresponding side (left or right). Furthermore, the upper part of the second link L2 is rotatably (swingably) connected to the rear part of the first link L1 located on the corresponding side (left or right). As shown in Figure 3, in the illustrated example, the second link L2 has a main link component 22 and an upper connecting component 23 fixed to the upper end of the main link component 22. The main link component 22 is, for example, made of a metal tube. The upper connecting component 23 is, for example, made of a resin molded material. The second link L2 is rotatably (swingably) connected to the rear end of the armrest 21 at the upper connecting component 23.

As shown in Figures 1-3, the third link L3 is rotatably (swingably) connected to the front leg 14. The fourth link L4 is rotatably (swingably) connected to the rear leg 16. The third link L3 is rotatably (swingably) connected to at least one of the second link L2 and the fourth link L4. The fourth link L4 is rotatably (swingably) connected to at least one of the second link L2 and the third link L3. The second link L2 is rotatably (swingably) connected to at least one of the third link L3 and the fourth link L4.

As shown in Figures 1 and 5, in the illustrated example, the components constituting the third link L3 include a frame component 24 and a front connecting component 25 and a rear connecting component 26 fixed to the frame component 24. The frame component 24 is, for example, made of a bent metal tube. The front connecting component 25 and the rear connecting component 26 are, for example, made of resin molding. The frame component 24 has a pair of sides 24a extending in the front-rear direction and a connecting portion 24b connecting the pair of sides 24a at the front, forming a U-shape. The front connecting component 25 connects one end to the front leg 14 in a rotatable manner, and the other end is fixed to the front portion of the side 24a. The rear connecting component 26 is fixed to the rear end portion of the side 24a. In this example, the third link L3 on the right side is formed by the side 24a of the frame component 24 located on the right side, and the front connecting component 25 and the rear connecting component 26 fixed to the right side of the side 24a. Similarly, the third link L3 on the left is formed by the side 24a of the frame member 24 on the left and the front connecting member 25 and the rear connecting member 26 on the left side of the side 24a fixed thereto.

As shown in Figure 5, in the illustrated example, the fourth link L4 has a main shaft component 28 rotatably connected to the rear leg 16 and an end component 29 fixed to the upper end of the main shaft component 28. The main shaft component 28 is, for example, made of a metal tube. The end component 29 is, for example, made of a resin molded material. The main shaft component 28 is rotatably connected to the middle part of the rear leg 16 at its lower end. The end component 29 is rotatably connected to the second link L2 and the third link L3. In the illustrated example, the second link L2, the third link L3, and the fourth link L4 are rotatably connected to each other using the same shaft component 30. This shaft component 30 passes through the main link component 22 of the second link L2, the end component 29 of the fourth link L4, and the rear connecting component 26 constituting the third link L3. According to this structure, the second link L2, the third link L3, and the fourth link L4 are configured to rotate relative to each other about an axis that coincides with the central axis of the shaft component 30.

Additionally, as shown in Figures 1 to 3, the main frame 12 of the illustrated stroller 10 also includes a base frame 31, an upper frame 32, and a connecting frame 33 connecting the base frame 31 and the upper frame 32. Both the base frame 31 and the upper frame 32 are U-shaped. Furthermore, in the illustrated stroller 10, a base fabric 34 (shown only in Figure 2) is stretched onto the frame member 24 and the base frame 31. The base fabric 34, together with the frame member 24, the base frame 31, the upper frame 32, and the connecting frame 33, supports the cushioning seat member 13 (shown only with a double-dotted line in Figure 2). Furthermore, the illustrations of the base frame 31, the upper frame 32, and the connecting frame 33 are omitted in Figure 4.

In the illustrated example, frame component 24, base frame 31, upper frame 32, connecting frame 33, and base fabric 34 constitute a seat support, thereby supporting seat component 13. A portion of the base fabric 34 and frame component 24 constitute a seat support for the infant's buttocks. Furthermore, a portion of the base fabric 34 and base frame 31 constitute a back support for the infant's back.

The base frame 31 is penetrated at both ends by shaft members 30 (see Figure 5). Furthermore, the base frame 31 is rotatable (swingable) relative to the frame member 24 and other structural elements. By swinging the base frame 31 relative to the frame member 24, the seat member 13 can be reclined. The upper frame 32 is rotatably (swingable) connected to the rear end portion of the first link L1 at both ends. The axis of rotation of the upper frame 32 relative to the first link L1 is on the same line as the axis of rotation of the second link L2 relative to the first link L1. A pair of connecting frames 33 are laterally separated between the base frame 31 and the upper frame 32. The connecting frames 33 are rotatably connected to the base frame 31 and the upper frame 32 at both ends.

As shown in Figure 1, the main frame 12 includes, as a structural element extending laterally, a front connecting member 15 connecting a pair of front legs 14 and a rear connecting member 17 connecting a pair of rear legs 16. In the illustrated example, the front connecting member 15 extends between a pair of first casters 50, and the rear connecting member 17 extends between a pair of second casters 60. The front connecting member 15 functions as a footrest. Furthermore, a central connecting member 27 is provided between a pair of rear connecting members 26. The front connecting member 15, the rear connecting member 17, and the central connecting member 27 help to prevent the stroller 10 from deforming laterally. Moreover, a flexible protective member 38 is detachably provided between a pair of first connecting rods L1.

The handle 40 is connected to the main frame 12 described above in a swingable manner. In the illustrated example, the handle 40 has a handle body 41 that is swingably mounted to the main frame 12 and a retainer 42 provided on the handle body 41. In the illustrated stroller body 11, the handle 40 can swing between a first position (rear push position) tilted backward relative to the vertical axis and a second position (facing push position) tilted forward relative to the vertical axis when viewed from the side.

As shown in Figure 1, the handle body 41 includes a pair of shaft portions 41a extending generally parallel to each other and an intermediate portion 41b connecting the pair of shaft portions 41a. The handle body 41 as a whole has a generally U-shaped shape. The handle 40 is rotatably (swinging) connected to the main frame 12 at both ends of the U. In the illustrated example, the handle body 41 is rotatably connected to the main frame 12 using shaft members 30. Therefore, the second link L2, the third link L3, the fourth link L4, the base frame 31, and the handle 40 can rotate relative to each other about the same axis defined by the shaft members 30.

A retainer 42 is mounted on the shaft portion 41a of the handle body 41. The retainer 42 is movable along the shaft portion 41a in the length direction of the shaft portion 41a. The handle 40 has a force-applying member (e.g., a spring, not shown) that presses the retainer 42 downwards. The retainer 42 can engage with a first position retaining member 36 and a second position retaining member 37 provided on the main frame 12. As shown in FIG3, the first position retaining member 36 is provided on the second link L2. By engaging the retainer 42 with the first position retaining member 36, the swing of the handle 40 relative to the main frame 12 is restricted, thereby maintaining the handle 40 in a first position as shown in FIG2. Moreover, as shown in FIG2, the second position retaining member 37 is provided on the first link L1. By engaging the retainer 42 with the second position retaining member 37, the swing of the handle 40 relative to the main frame 12 is restricted, thereby maintaining the handle 40 in a second position as shown in FIG3. For example, by moving the retaining body 42, which has moved upward against the force of the force-applying component, downward to cover the first position retaining member 36 or the second position retaining member 37, the retaining body 42 can be engaged with the first position retaining member 36 or the second position retaining member 37.

The stroller body 11 with the above structure can be folded by rotating the various structural components relative to each other. Specifically, the handle 40, which is positioned in the first position, is temporarily pulled up and then pressed down, thereby causing the fourth link L4 to rotate clockwise relative to the rear leg 16 in FIG. 2. Along with this operation, the first link L1 and the third link L3 rotate clockwise relative to the second link L2 in FIG. 2. Through this operation, when viewed from the side, the handle 40 and the front leg 14 approach each other while maintaining a roughly parallel configuration, and the position of the handle 40 decreases. As described above, as shown in FIG. 4, the stroller body 11 can be folded. In the folded state shown in FIG. 4, the stroller 10 can be miniaturized in both the front-to-back and vertical directions. On the other hand, to unfold the stroller body 11 from the folded state, only the reverse steps of the folding operation described above need to be performed.

In addition, the stroller body 11 has a state-maintaining mechanism (not shown) that restricts the relative rotation of the two structural components. By operating this state-maintaining mechanism, the stroller body 11 can be folded. Furthermore, in the illustrated example, the handle 40 has a remote operating device 43 connected to the state-maintaining mechanism. As shown in FIG1, the remote operating device 43 is located in the middle portion 41b of the handle body 41. By operating the remote operating device 43, the state-maintaining mechanism is activated, thereby enabling the folding of the stroller body 11.

Next, the first caster 50 and the second caster 60 will be described. In the illustrated example, the stroller body 11 has a pair of front legs 14, each front leg 14 holding a first caster 50. The pair of first casters 50 have the same structure or a structure that is approximately symmetrical about a plane located at the lateral center and centered on the front-back and up-down directions. Similarly, the stroller body 11 has a pair of rear legs 16, each rear leg 16 holding a second caster 60. The pair of second casters 60 have the same structure or a structure that is approximately symmetrical about a plane located at the lateral center and centered on the front-back and up-down directions. Hereinafter, the first caster 50 and the second caster 60 located on the left side in the lateral direction, as shown in Figures 1 to 6, will be described.

As shown in Figure 5, the first caster 50 includes: a first fixed body 51 mounted on the lower end portion of the front leg 14; a first rotating body 52 rotatably supported on the first fixed body 51; and a front wheel 56 rotatably supported on the first rotating body 52. The first rotating body 52 is connected to the first fixed body 51. The first rotating body 52 is rotatable relative to the first fixed body 51 about a first caster axis C1 extending in the vertical direction (see Figure 2). The first rotating body 52 has a first opposing surface SS1 facing the first fixed body 51 from below. In particular, in the illustrated example, the first rotating body 52 contacts the first fixed body 51 from below at the first opposing surface SS1. During the relative rotation of the first rotating body 52 and the first fixed body 51 about the first caster axis C1, the first fixed body 51 slides relative to the first opposing surface SS1 of the first rotating body 52.

As shown in Figure 5, the first rotating body 52 has a first rotating body base 53 connected to a first fixed body 51, a first rotating body retainer 54 connected to the first rotating body base 53, and a first axle 55 supported on the first rotating body retainer 54. In this example, the first rotating body base 53 includes a first opposing surface SS1. The first rotating body base 53 is rotatable relative to the first fixed body 51 about a first caster axis C1. The first rotating body retainer 54 is connected to the first rotating body base 53, for example, via a shock-absorbing buffer member.

The illustrated first rotating body retainer 54 has a connecting portion 54a connected to the first rotating body base 53 and a pair of arm portions 54b extending from the connecting portion 54a. As an example, the connecting portion 54a has a hole for inserting a shaft portion extending downward from the first fixed body 51, thereby preventing the shaft portion of the first fixed body 51 from being pulled out of the hole in the connecting portion 54a. With this structure, the first fixed body 51 and the first rotating body 52 are connected in a rotatable manner. The arm portions 54b have a length direction. The pair of arm portions 54b extend from the connecting portion 54a in a manner parallel to each other in their length directions and separated from each other in a direction perpendicular to their length directions. A first axle 55 is supported on the end of the pair of arm portions 54b on the side away from the connecting portion 54a. The first axle 55 extends parallel to the running surface. A front wheel 56 is supported on the first axle 55. Therefore, the front wheel 56 is rotatably arranged between the pair of arm portions 54b. That is, each first caster 50 has only one front wheel 56.

As shown in Figure 6, in the width direction of the stroller 10 in its straight-moving state, the width of the first opposing surface SS1 is smaller than the width W54 of the rotating body retainer 54, and the first opposing surface SS1 is located within the area of the rotating body retainer 54. In this example, in the vertical projection, the first opposing surface SS1 is located on the rotating body retainer 54 that holds the front wheel 56. Furthermore, in the width direction of the stroller 10 in its straight-moving state, the front wheel 56 is located on the first caster axle C1 of the first caster 50. Therefore, the first rotating body 52 can stably support the first fixed body 51 via the first opposing surface SS1, thereby stabilizing the stroller's movement. Additionally, in the illustrated example, the width of the first opposing surface SS1 is the same as the maximum width W53 of the first rotating body base.

As shown in Figure 5, the first caster 50 also has a braking member 57 that is movably disposed on the first swivel cage 54 supporting the front wheel 56. The braking member 57, by moving relative to the first swivel cage 54, can contact the front wheel 56 to restrict its rotation. The illustrated braking member 57 is supported in a swingable manner on an arm 54b located inside the width direction of the first swivel cage 54.

In addition, the inner side (inner side) in the width direction refers to the side closer to the center of the stroller 10 in the width direction. The outer side (outer side) in the width direction refers to the side farther away from the center of the stroller 10 in the width direction.

As shown in Figure 5, the second caster 60 has a second fixed body 61 mounted on the lower end portion of the rear leg 16, a second rotating body 62 rotatably supported on the second fixed body 61, and a rear wheel 66 rotatably supported on the second rotating body 62. The second rotating body 62 is connected to the second fixed body 61. The second rotating body 62 is rotatable relative to the second fixed body 61 about a second caster axis C2 extending vertically (see Figure 2). The second rotating body 62 has a second opposing surface SS2 facing the second fixed body 61 from below. In particular, in the illustrated example, the second rotating body 62 contacts the second fixed body 61 from below at the second opposing surface SS2. During the relative rotation of the second rotating body 62 and the second fixed body 61 about the second caster axis C2, the second fixed body 61 slides relative to the second opposing surface SS2 of the second rotating body 62.

As shown in Figure 5, the second rotating body 62 has a second rotating body base 63 connected to the second fixed body 61 and a second axle 65 supported on the second rotating body base 63. In this example, the second rotating body base 63 includes a second opposing surface SS2. The second axle 65 passes through the second rotating body base 63 and extends to both sides of the second rotating body base 63. The second axle 65 extends parallel to the running surface. Rear wheels 66 are rotatably supported on the portions of the second axle 65 extending to both sides from the second rotating body base 63. That is, each first caster 50 has a pair of rear wheels 66. The second rotating body base 63 is located between the pair of rear wheels 66.

As shown in Figure 1, the second caster 60 also has a braking member 67 that is movably mounted on the second rotating body base 63 supporting the rear wheel 66. The braking member 67, by moving relative to the second rotating body base 63, can contact the rear wheel 66 to restrict its rotation. The illustrated braking member 67 is supported on the second rotating body base 63 in a swingable manner.

Additionally, as shown in Figure 2, the first caster 50 has a locking member 58 that restricts the rotation of the first rotating body 52 relative to the first fixed body 51. This locking member 58 is movable between a restricted position and an unrestricted position. For example, when in the restricted position, the locking member 58 protrudes from the first fixed body 51 and contacts the first rotating body 52, thereby restricting the first rotating body 52 from rotating relative to the first fixed body 51 about the first caster axis C1. On the other hand, when in the unrestricted position, the locking member 58 is away from the first rotating body 52, thus not interfering with the rotation of the first rotating body 52 relative to the first fixed body 51.

Similarly, as shown in FIG2, the second caster 60 has a locking member 68 that restricts the rotation of the second rotating body 62 relative to the second fixed body 61. This locking member 68 is movable between a restricted position and an unrestricted position. For example, in the restricted position, the locking member 68 protrudes from the second fixed body 61 and contacts the second rotating body 62, thereby restricting the rotation of the second rotating body 62 relative to the second fixed body 61 about the second caster axis C2. On the other hand, in the unrestricted position, the locking member 68 is disengaged from the second rotating body 62, thus not interfering with the rotation of the second rotating body 62 relative to the second fixed body 61.

Furthermore, as shown in FIG2, the stroller body 11 has a switching mechanism 45 that moves the locking members 58 and 68 between a restricted position and an unrestricted position depending on the position of the handle 40. In the illustrated example, the switching mechanism 45 has a switching member 46 supported on the rear leg 16 in an actuating manner and a transmission member 47 connecting the switching member 46 and the locking members 58 and 68. In the illustrated example, the switching member 46 contacts the handle 40 as the handle 40 swings. Contact with the handle 40 causes a relative movement of the switching member 46 relative to the rear leg 16, such as a linear or rotational movement; specifically, it can cause a relative swinging movement. The movement of the switching member 46 actuates the locking members 58 and 68 via the transmission member 47.

Furthermore, in this embodiment, when the handle 40 is in the second position, the rotation of the first rotating body 52 of the first caster 50 relative to the first fixed body 51 is restricted. Similarly, when the handle 40 is in the first position, the rotation of the second rotating body 62 of the second caster 60 relative to the second fixed body 61 is restricted. In the illustrated example, when the handle 40 is in the first position (the position of the handle 40 shown in FIG. 2), rotation of the first rotating body 52 of the first caster 50 is allowed, while rotation of the second rotating body 62 of the second caster 60 is restricted. On the other hand, when the handle 40 is in the second position (the position of the handle 40 shown in FIG. 3), the rotation of the first rotating body 52 of the first caster 50 is restricted, while rotation of the second rotating body 62 of the second caster 60 is allowed.

Furthermore, the switching mechanism 45 and the locking components 58 and 68 can adopt various known structures, such as those disclosed in Japanese Patent Application Publication No. 2008-254688, Japanese Patent Application Publication No. 2008-254693, and Japanese Patent Application Publication No. 2010-234988.

Next, the function of the stroller 10 constructed with the above structure will be explained. As described above, the handle 40 can swing between a first position and a second position relative to the main frame 12.

As shown in Figure 2, when the handle 40 is positioned in the first position as the rear-pushing position, the operator (guardian) can hold the handle 40 from the back of the infant to manipulate the stroller 10, thereby moving the stroller 10 with the infant facing forward in the direction of travel. At this time, the front legs 14 are in front of the stroller 10 in the direction of travel, and the rear legs 16 are behind the stroller 10 in the direction of travel. Furthermore, in the first caster 50 mounted on the front legs 14, the first rotating body 52 can rotate relative to the first fixed body 51 about the first caster axis C1. On the other hand, in the second caster 60 mounted on the rear legs 16, the second rotating body 62 cannot rotate relative to the second fixed body 61 about the second caster axis C2.

As shown in Figure 3, when the handle 40 is positioned in the second position facing the push position, the operator holds the handle 40 from the side facing the infant's front leg 14 to operate the stroller 10, thereby enabling the stroller 10 to move with its rear leg side in front of the direction of travel. At this time, the rear leg 16 is in front of the stroller 10 in the direction of travel, and the front leg 14 is behind the stroller 10 in the direction of travel. Furthermore, in the first caster 50 mounted on the front leg 14, the first rotating body 52 cannot rotate relative to the first fixed body 51 around the first caster axis C1. On the other hand, in the second caster 60 mounted on the rear leg 16, the second rotating body 62 can rotate relative to the second fixed body 61 around the second caster axis C2.

That is, by switching the holding position of the handle 40 between a first position and a second position, the ability to rotate the rotating bodies 52 and 62 supporting the wheels 56 and 66 around the caster axes C1 and C2 can be switched. Specifically, the casters 50 and 60 located at the front in the direction of movement of the stroller 10 function as casters, and the rotating bodies 52 and 62 supporting the wheels 56 and 66 rotate around the caster axes C1 and C2. On the other hand, the casters 50 and 60 located at the rear in the direction of movement of the stroller 10 do not function as casters, and the rotation of the rotating bodies 52 and 62 supporting the wheels 56 and 66 around the caster axes C1 and C2 is restricted. By switching the caster mechanism according to the swing position of the handle 40, the operator's (guardian's) maneuverability of the stroller 10 can be improved.

Furthermore, when the handle 40 is in the first position, which is the rear-facing push position, the infant can face forward in the direction of travel. Therefore, while the stroller 10 is moving, the infant can observe and enjoy the scenery. When the handle 40 is in the second position, which is the facing push position, the caregiver can check the infant's condition while moving the stroller 10. Therefore, when placing a young infant in the stroller 10, the handle 40 is usually positioned in the second position, which is the facing push position, while when placing an infant who can sit up in the stroller 10, the handle 40 is usually positioned in the first position, which is the rear-facing push position.

When placing a young infant in stroller 10, stroller 10 requires walking stability. According to the illustrated stroller 10, in a push-facing position intended for young infants, where the handle 40 is positioned as a second push-facing position, the rear legs 16 are located at the front in the direction of movement. Furthermore, the second caster 60 mounted on the rear legs 16 has a double-wheel structure, comprising a pair of rear wheels 66. This second caster 60 features a large contact area, high strength, and excellent load-bearing capacity. Therefore, when the second caster 60 is located at the front in the direction of movement and functions as a caster, excellent walking stability is achieved due to its double-wheel structure.

Furthermore, the second caster 60 of the dual-wheel structure has a pair of rear wheels 66 that are separated in a direction perpendicular to the direction of travel. Therefore, it is possible to effectively prevent the second caster 60 as a whole, i.e., both of the rear wheels 66, from becoming embedded in grooves or other recesses formed in the walking surface. That is, even if one rear wheel 66 of one second caster 60 is located on a recess, the other rear wheel 66 remains on the walking surface, thus effectively preventing the second caster 60 from becoming embedded in the recess. This effectively suppresses unwanted impacts, thereby improving walking stability.

That is, in the stroller 10 with the handle 40 in the second position facing the push position, the second caster 60 functions as a caster located in the forward direction of movement, thereby providing appropriate walking stability required by the young infants who tend to be placed in the stroller 10.

On the other hand, as infants grow, their weight increases. With this weight increase, the stroller 10 requires greater maneuverability (steering, walking maneuverability). Furthermore, as described above, as infants grow, the stroller 10 is used with the handle 40 positioned in a first position as the rear-pushing position, allowing the infant to enjoy outings using the stroller 10. In the stroller 10 of this embodiment, with the handle 40 positioned in the first position as the rear-pushing position, the front legs 14 are located in front of the direction of movement. Moreover, the first caster 50 mounted on the front legs 14 has a single-wheel structure, including only one front wheel 56. In this first caster 50, the frictional resistance between the walking surface and the front wheel 56 is reduced, making it easier for the first rotating body 52 to rotate relative to the first fixed body 51 about the first caster axis C1. Therefore, by applying force to the handle 40, the front wheel 56 and the first rotating body 52 can be easily rotated relative to the first fixed body 51, thus providing excellent maneuverability.

As described above, by positioning the handle 40 in the second position, which is the facing-pushing position, the second caster 60 functions as a caster located forward in the direction of movement, thereby providing the stroller 10 with the walking stability required for young infants who are inclined to be placed in the stroller 10. On the other hand, by positioning the handle 40 in the first position, which is the rear-pushing position, the first caster 50 functions as a caster located forward in the direction of movement, thereby providing the stroller 10 with the maneuverability required for older infants who are inclined to be placed in the stroller 10. That is, depending on the configuration of the swingable handle 40, the characteristics of the stroller 10 can be changed, and in particular, the stroller 10 can be given the characteristics required according to the position of the handle 40.

Furthermore, the main frame 12 of the illustrated stroller 10 includes: a first link L1 rotatably connected to the front leg 14 and the rear leg 16; a second link L2 rotatably connected to the rear end portion of the first link L1; a third link L3 rotatably connected to the front leg 14; and a fourth link L4 rotatably connected to the middle portion of the rear leg 16. The second link L2 is rotatably connected to at least one of the third link L3 and the fourth link L4. Furthermore, the third link L3 is rotatably connected to at least one of the fourth link L4 and the second link L2. Finally, the fourth link L4 is rotatably connected to at least one of the second link L2 and the third link L3.

In this stroller 10, the center of gravity of the infant placed in the stroller 10 is closer to the rear leg 16 in the front-to-back direction than to the front leg 14. Specifically, in the illustrated stroller 10, when viewed from the side as shown in Figures 2 and 3, the connection point (position of the shaft member 30) where the third link L3 connects to the fourth link L4 and the second link L2 is located further back than the rear leg 16. Therefore, in this stroller 10, the infant's center of gravity is more likely to be closer to the rear leg 16 in the front-to-back direction than to the front leg 14. Thus, in the illustrated stroller 10, the infant's weight is primarily supported by the rear leg 16 and the second caster 60 fixed to the lower end of the rear leg 16. As described above, the second caster 60 has a pair of rear wheels 66 separated in the width direction. Therefore, the second caster 60 has a large contact area, high strength, and excellent load-bearing capacity. Thus, according to the illustrated stroller 10, the infant's weight can be stably supported.

Furthermore, the center of gravity of an infant or toddler placed in a stroller typically depends on the reclining angle, but is generally located behind the seat support that supports the infant's buttocks. In particular, the center of gravity of an infant or toddler in a stroller tends to be located near the connection point where the seat support connects to the back support that supports the infant's back. In the illustrated stroller 10, the base fabric 34 and the frame member 24 of the adjustable base fabric 34 constitute the seat support that supports the infant's buttocks via the seat member 13. Moreover, the base frame 31 of the base fabric 34 and the adjustable base fabric 34 constitutes the back support that supports the infant's back via the seat member 13. Therefore, the center of gravity CG of an infant or toddler placed in the illustrated stroller 10 does not depend on the position of the swing handle 40 as shown in Figures 7A and 7B, but is located behind the frame member 24 in the front-rear direction, or more precisely, at the rotatable connection point between the base frame 31 and the frame member 24, i.e., around the axle member 30. Therefore, the center of gravity CG of the infant placed in the stroller 10 is closer to the hind legs 16 in the front-to-back direction than to the front legs 14. Thus, the infant's weight is stably supported by the second caster 60 mounted on the hind legs 16 and including a pair of rear wheels 66.

Furthermore, as shown in Figures 7A and 7B, the longitudinal distance LY from the infant's center of gravity CG to the contact point of the rear wheel 66 is shorter than the longitudinal distance LX from the infant's center of gravity CG to the contact point of the front wheel 56. This results in a stroller 10 whose stability in the width direction is dependent on the width direction position of the rear wheel 66, despite swaying, warping, deformation, tipping (tilting), etc.

On the other hand, as shown in Figure 6, the rear wheel 66 of each second caster 60 located on the outer side in the width direction is further outward than the front wheel 56 of the first caster 50 located on the same side (left or right) in the width direction as the second caster 60. Therefore, the tipping angle θ2 (see Figure 8A) of the stroller 10 where the infant's center of gravity CG is located further outward than the rear wheel 66 in the width direction is larger than the tipping angle θ1 (see Figure 8B) of the stroller 10 where the infant's center of gravity CG is located further outward than the front wheel 56 in the width direction. Therefore, in the illustrated stroller 10, the second caster 60, which includes a pair of rear wheels 66, provides excellent stability against lateral swaying, warping, deformation, tipping (tilting), etc.

In particular, in the illustrated stroller 10, the front legs 14 and rear legs 16 are located in areas that overlap each other in the width direction, and the front legs 14 and the front wheels 56 of the first casters 50 are also located in areas that overlap each other in the width direction. Furthermore, in the width direction, the front wheels 56 of each first caster 50 are located between a pair of rear wheels 66 of the second casters 60 located on the same side of the first caster 50 in the width direction. Therefore, excellent stability can be ensured against deformation or tilting in the width direction, while preventing the stroller 10 from becoming too large and giving it an excellent appearance.

In particular, in the illustrated stroller 10, as shown in Figure 6, in the width direction of its straight-line travel, the front wheel 56 of each first caster 50 is located at the center of a pair of rear wheels 66 of the second caster 60, which are on the same side of the first caster 50 in the width direction. Therefore, walking stability can be further improved, thereby enabling excellent straight-line travel.

Furthermore, in the illustrated stroller 10, in the width direction, the first wheel axis C1 of each first caster 50 is located at the same position as the second wheel axis C2 of the second caster 60 located on the same side as the first caster 50. Therefore, walking stability can be improved, and steering and walking maneuverability can be enhanced.

Furthermore, as shown in Figure 2, the diameter D1 of the front wheel 56 of the first caster 50 is smaller than the diameter D2 of the rear wheel 66 of the second caster 60. With this first caster 50, it is easier to generate rotation of the first rotating body 52 about the first caster axis C1 relative to the first fixed body 51. This further improves the maneuverability of the stroller 10 when the handle 40 is in the first position, which is the rear push position.

Furthermore, the stroller 10 shown in the figure can only be folded from the unfolded state when the handle 40 is in the first position. Moreover, in the folded stroller 10, similar to the stroller 10 with the handle 40 in the first position, the first rotating body 52 and the front wheel 56 of the first caster 50 are allowed to rotate relative to the first fixed body 51, while the second rotating body 62 and the rear wheel 66 of the second caster 60 are restricted from rotating relative to the second fixed body 61. That is, in the folded state, the diameter of the front wheel 56, which can rotate relative to the first fixed body 51 about the first caster axis C1, is smaller. According to this stroller 10, as shown in FIG. 4, the upright posture of the stroller 10 in the folded state can be effectively stabilized.

Furthermore, as shown in Figure 6, in the stroller 10 in a straight-moving state, that is, in the stroller 10 moving in a direction parallel to the front-rear direction, the front wheel 56 of each first caster 50 is located between a pair of rear wheels 66 of the second caster 60, which are on the same side in the width direction as the first caster 50. In particular, the outer end of the front wheel 56 in the width direction is further inward in the width direction than the inner end of the rear wheel 66, which is located on the outer side in the width direction, and the inner end of the front wheel 56 in the width direction is further outward in the width direction than the outer end of the rear wheel 66, which is located on the inner side in the width direction. In other words, in the stroller 10 in a straight-moving state, the width-direction spacing S2 of the pair of rear wheels 66 is larger than the width-direction width W1 of the front wheels 56. With such a stroller 10, tipping over in the width direction can be effectively suppressed, and the straight-moving state of the stroller 10 can be effectively stabilized.

Furthermore, in the example shown in Figure 6, the distance S2 between the pair of rear wheels 66 in the width direction of the stroller 10 in a straight-moving state is greater than the width W51 of the first fixing body 51. Moreover, in the stroller 10 in a straight-moving state, the distance S2 between the pair of rear wheels 66 in the width direction is greater than the width W53 of the first rotating body base 53 of the first rotating body 52 in the width direction, and also greater than the width W54 of the first rotating body retainer 54 of the first rotating body 52 in the width direction. According to this example, the maneuverability is excellent when the handle 40 is in the first position as a rear-pushing position (the position of the handle 40 shown in Figure 2), and the walking stability is even better when the handle 40 is in the second position as a facing-pushing position (the position of the handle 40 shown in Figure 3).

In one embodiment described above, the stroller 10 includes: a main frame 12 having front legs 14 and rear legs 16; a handle 40 connected to the main frame 12 in a manner capable of swinging between a first position and a second position; a first caster 50 mounted on the front leg 14; and a second caster 60 mounted on the rear leg 16. The first caster 50 includes: a first fixed body 51 fixed to the front leg 14; a first rotating body 52 supported on the first fixed body 51 in a manner rotatable about a first caster axis C1; and a single front wheel 56 rotatably supported on the first rotating body 52. The second caster 60 includes: a second fixed body 61 fixed to the rear leg 16; a second rotating body 62 supported on the second fixed body 61 in a manner rotatable about a second caster axis C2; and a pair of rear wheels 66 rotatably supported on the second rotating body 62. Furthermore, when the handle 40 is in the second position, the rotation of the first rotating body 52 relative to the first fixed body 51 is restricted, and when the handle 40 is in the first position, the rotation of the second rotating body 62 relative to the second fixed body 61 is restricted.

According to this embodiment, by placing the handle 40 in the second position, the second caster 60 functions as a caster located forward in the direction of movement, thereby improving the walking stability of the stroller 10. On the other hand, by placing the handle 40 in the first position, the first caster 50 functions as a caster located forward in the direction of movement, thereby improving the maneuverability of the stroller 10. That is, the characteristics of the stroller 10 can be changed depending on the configuration of the swingable handle 40.

Furthermore, in the example shown in Figure 6, in the width direction of the stroller 10 in a straight-moving state, the width W2 of the rear wheel 66 is narrower than the width W1 of the front wheel 56. Based on this example, walking stability can be maintained when the handlebar 40 is in the second position, and maneuverability can be maintained when the handlebar 40 is in the first position. Moreover, maneuverability when the handlebar 40 is in the second position can be improved, and walking stability when the handlebar 40 is in the first position can be improved.

Furthermore, in the illustrated stroller 10, the front wheel 56 of the first caster 50 overlaps with the position of the first fixed body 51 in the width direction. Moreover, the front wheel 56 of the first caster 50 overlaps with the first caster axis C1 in the width direction. As shown in Figure 2, in such a stroller 10, it has been confirmed that by increasing the height H1 of the first opposing surface SS1 of the first rotating body 52 of the first caster 50, it is easier to rotate the first rotating body 52 relative to the first fixed body 51 around the caster axis C1 when the handle 40 is positioned in the first position. That is, by increasing the height H1 of the first opposing surface SS1, the maneuverability when the handle 40 is positioned in the first position can be further improved.

On the other hand, in the illustrated stroller 10, the rear wheel 66 of the second caster 60 is located offset from the second fixed body 61 in the width direction. Therefore, the rear wheel 66 of the second caster 60 is offset from the second caster axis C2 in the width direction. As shown in FIG2, in such a stroller 10, it has been confirmed that by lowering the height H2 of the second opposing surface SS2 of the second rotating body 62 of the second caster 60, undesirable rotation of the second fixed body 61 relative to the second rotating body 62 about the caster axis C1 can be effectively suppressed when the handle 40 is positioned in the second position. That is, by lowering the height H2 of the second opposing surface SS2, walking stability when the handle 40 is positioned in the second position can be further improved.

Furthermore, in the illustrated example, the height H1 of the first opposing surface SS1 is higher than the height H2 of the second opposing surface S2. The height H1 of the first opposing surface SS1 is greater than or equal to the diameter D1 of the front wheel 56. The height H1 of the first opposing surface SS1 is greater than or equal to the diameter D2 of the rear wheel 66. With this structure, the maneuverability of the handlebar 40 in the first position can be improved.

Similarly, in the illustrated example, the height H1 of the first opposing surface SS1 is higher than the height H2 of the second opposing surface S2. The height H2 of the second opposing surface SS2 is less than the diameter D1 of the front wheel 56. The height H2 of the second opposing surface SS1 is less than the diameter D2 of the rear wheel 66. With this structure, the walking stability of the handlebar 40 in the second position is improved.

An embodiment has been described with reference to the illustrated examples, but the illustrated examples are not intended to limit the scope of the embodiment. The above-described embodiment can be implemented in various other embodiments, and various omissions, substitutions, modifications, additions, etc., can be made without departing from its spirit. For example, in the above-described embodiment, the stroller 10 can begin to fold from the unfolded state to the folded state only when the handle 40 is in the first position, but it is not limited to this. For example, the stroller 10 can begin to fold only when the handle 40 is in the second position, or the stroller 10 can begin to fold regardless of whether the handle 40 is in the first or second position.

Claims (5)

1. A stroller, comprising: The main frame has front legs and hind legs; The first caster, mounted on the front leg, has a single-wheel structure; and The second caster, mounted on the rear leg, has a dual-wheel structure. The first caster includes a single front wheel. The second caster includes a pair of rear wheels. The diameter of the front wheel is smaller than the diameter of the rear wheel. When traveling straight, in the width direction, the front wheel of each first caster is located in the area containing the center position of the pair of rear wheels of the second caster which is on the same side as the first caster in the width direction. 2. A stroller, comprising: The main frame has front legs and hind legs; The first caster, mounted on the front leg, has a single-wheel structure; and The second caster, mounted on the rear leg, has a dual-wheel structure. The first caster includes a single front wheel. The second caster includes a pair of rear wheels. The width of the rear wheel is smaller than the width of the front wheel. When traveling straight, in the width direction, the front wheel of each first caster is located in the area containing the center position of the pair of rear wheels of the second caster which is on the same side as the first caster in the width direction. 3. The stroller according to claim 1 or 2, wherein, The stroller has a handle that is connected to the main frame in a manner that allows it to swing between a first position and a second position. The stroller can only be folded from the unfolded state when the handle is in the first position. 4. The stroller according to claim 1 or 2, wherein, The stroller has a handle that is connected to the main frame in a manner that allows it to swing between a first position and a second position. The rotation of the first caster is restricted when the handle is in the second position, and the rotation of the second caster is restricted when the handle is in the first position. 5. The stroller according to claim 1 or 2, wherein, The stroller has a handle that is connected to the main frame in a manner that allows it to swing between a first position and a second position. The first caster has a first fixed body fixed to the front leg, a first rotating body supported on the first fixed body in a manner rotatable about the first caster axis, and a single front wheel supported on the first rotating body in a rotatable manner. The second caster has a second fixed body fixed to the rear leg, a second rotating body supported on the second fixed body in a manner that allows it to rotate about the axis of the second caster, and the pair of rear wheels supported on the second rotating body in a manner that allows them to rotate.