Childcare appliance with wheels

Abstract

To provide a childcare appliance with wheels having a simple structure.SOLUTION: A childcare appliance with wheels includes: a vehicle body frame (10); caster mechanisms (30, 40) including caster holding members (31, 41) and caster rotation members (32, 42) and enabling turning of a direction of a front wheel (12) or a rear wheel (14); caster lock members (35, 45) that are provided in the caster mechanisms (30, 40) and are put into a lock position and an unlock position; displacement members (52, 56) that are connected to the caster lock members (35, 45) via connection members (51, 55) and displaced between a first position corresponding to the lock position of the caster lock members (35, 45) and a second position corresponding to the unlock position of the caster lock members (35, 45) in response to switching of a push rod (20); and an operation mechanism (22) that is provided in a push rod (20) and is operable to bring the displacement members (52, 56) from the first position to the second position.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a wheeled childcare apparatus. [Background technology]

[0002] Conventionally, strollers have been known that have a push bar that can slide back and forth to switch between rear-facing and front-facing pushes. Such strollers have front and rear wheels with caster wheels, and it is desirable that the front wheels are caster-free (turnable) and the rear wheels are caster-locked (non-turnable).

[0003] When locking the desired caster wheels, it is cumbersome for the stroller operator to manually operate the caster locks for each wheel individually. Therefore, a so-called automatic four-wheel mechanism is known in the past that automatically caster-frees the wheels at the front in the direction of travel and caster-locks the wheels at the rear in the direction of travel in conjunction with the forward and backward position of the push bar, without the stroller operator having to go to the trouble of operating each caster wheel to enable or disable swivel.

[0004] Various structures are known for automatic four-wheel mechanisms in strollers that release the caster wheels at the front of the stroller in the direction of travel so that they can be turned, and lock the caster wheels at the rear of the stroller in the direction of travel so that they cannot be turned.For example, Patent Publication No. 2008-254688 (Patent Document 1), Patent Publication No. 2013-6553 (Patent Document 2), and Patent Publication No. 2021-041921 (Patent Document 3) are known.

[0005] Patent documents 1 and 2 disclose a stroller in which the push rod can be switched between a forward-pushing position and a rear-pushing position, and when the push rod is swung forward it comes into contact with a lock switching member and pushes down the lock switching member, and the lock switching member slides downward with the push rod to lock the caster wheels on the front legs so that they cannot be turned, and release the caster wheels on the rear legs so that they can be turned.

[0006] Furthermore, Patent Document 3 discloses that when the push rod is in the facing-pushing position and an operating section provided on the push rod is operated, the caster wheels are released so that they can be turned. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-254688 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-6553 [Patent Document 3] Patent Publication No. 2021-041921 Summary of the Invention [Problem to be solved by the invention]

[0008] The strollers disclosed in Patent Documents 1 and 2 allow the caster wheels to be switched between swivelable and inoperable by switching the push bar, while the stroller disclosed in Patent Document 3 allows the caster wheels to be intentionally switched into a swivelable state by operating an operating part on the push bar, rather than by switching the push bar. However, the structure for switching the caster wheels between swivelable and inoperable in both strollers has many parts and is complex in structure.

[0009] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a childcare implement with wheels that has a simple structure. [Means for solving the problem]

[0010] To this end, one embodiment of the present invention provides a wheeled childcare device comprising: a body frame including front legs, rear legs, and a push bar that can be switched between a rear-facing position and a forward-facing position; a caster mechanism that has a caster holding member attached to the lower end of the front or rear leg, and a caster rotation member that is rotatably held by the caster holding member around a rotation axis extending in the vertical direction and supports the front or rear wheel, thereby allowing the front or rear wheel to be turned; a caster locking member attached to the caster mechanism that restricts the rotation of the caster rotation member in a locked position and allows the caster rotation member in an unlocked position; a displacement member attached to the body frame and connected to the caster locking member via a connecting member that displaces between a first position corresponding to the locked position of the caster locking member and a second position corresponding to the unlocked position of the caster locking member as the push bar is switched; and an operating mechanism attached to the push bar that can operate the displacement member from the first position to the second position.

[0011] Preferably, the wheeled child care apparatus further comprises a first biasing member that biases the displacement member to the second position.

[0012] Preferably, the operating mechanism includes an operating member and a drive member connected to the operating member and switched between a first state and a second state by the operating force of the operating member, the drive member in the first state bringing the displacement member to the first position, and the drive member in the second state bringing the displacement member to the second position.

[0013] Preferably, the operating mechanism includes an operating member and a drive member connected to the operating member and switched between a first state and a second state by the operating force of the operating member, wherein the drive member in the first state blocks the biasing force of the first biasing member acting on the displacement member, and the drive member in the second state enables the biasing force of the first biasing member acting on the displacement member.

[0014] Preferably, the operating mechanism further includes a second biasing member that biases the drive member toward the first state, and the biasing force of the second biasing member is greater than the biasing force of the first biasing member.

[0015] Preferably, the wheeled child care apparatus further includes a third biasing member that biases the caster locking member to the locked position, the biasing force of the third biasing member being smaller than the biasing force of the first biasing member.

[0016] Preferably, the caster mechanism has a front caster holding member provided at the lower end of the front leg, and a front caster rotating member that is rotatably held by the front caster holding member around a rotation axis extending in the vertical direction and supports the front wheel, thereby enabling the front wheel to rotate; a rear caster holding member provided at the lower end of the rear leg, and a rear caster rotating member that is rotatably held by the rear caster holding member around a rotation axis extending in the vertical direction and supports the rear wheel. and a rear caster mechanism having a pivoting member that enables the rear wheels to turn in a directional direction, and the caster locking member is provided on the front caster mechanism and includes a front caster locking member that restricts the rotation of the front caster pivoting member in a locked position and allows the rotation of the front caster pivoting member in an unlocked position, and a rear caster locking member that is provided on the rear caster mechanism and restricts the rotation of the rear caster pivoting member in a locked position and allows the rotation of the rear caster pivoting member in an unlocked position.

[0017] Preferably, the displacement members include a front-wheel-side displacement member provided on the front legs, connected to the front caster locking members, and pressed by the push rod as the push rod is switched, thereby displacing between a first position corresponding to the locked position of the front caster locking members and a second position corresponding to the unlocked position of the front caster locking members; and a rear-wheel-side displacement member provided on the rear legs, connected to the rear caster locking members, and pressed by the push rod as the push rod is switched, thereby displacing between a first position corresponding to the locked position of the rear caster locking members and a second position corresponding to the unlocked position of the rear caster locking members.

[0018] Preferably, the displacement member is provided so as to be movable up and down along the body frame.

[0019] Preferably, the displacement member is provided rotatably with respect to the body frame.

[0020] Another aspect of the present invention provides a wheeled childcare device comprising a body frame including front legs, rear legs, and a push bar; a caster mechanism having caster holding members attached to the lower ends of the front or rear legs and caster rotation members held by the caster holding members so as to be rotatable about a rotation axis extending in the vertical direction and supporting the front or rear wheels, thereby allowing the front or rear wheels to be turned; a caster locking member attached to the caster mechanism and restricting the rotation of the caster rotation member in a locked position and allowing the rotation of the caster rotation member in an unlocked position; a displacement member attached to the body frame and connected to the caster locking member via a connecting member and displaceable between a first position corresponding to the locked position of the caster locking member and a second position corresponding to the unlocked position; a first biasing member that biases the displacement member to the second position; and a drive member attached to the push bar and switchable between a first state corresponding to the displacement member in the first position and a second state corresponding to the displacement member in the second position.

[0021] Preferably, the wheeled childcare device further comprises an operating mechanism provided on the push rod and operable to operate the displacement member from a first position to a second position, the operating mechanism including an operating member and a drive member connected to the operating member and switched between a first state and a second state by the operating force of the operating member, the drive member in the first state blocking the biasing force of the first biasing member acting on the displacement member, and the drive member in the second state enabling the biasing force of the first biasing member acting on the displacement member.

[0022] Preferably, the operating mechanism further includes a second biasing member that biases the drive member toward the first state, and the biasing force of the second biasing member is greater than the biasing force of the first biasing member.

[0023] Preferably, the apparatus further includes a third biasing member that biases the caster locking member toward the locked position, and the biasing force of the third biasing member is smaller than the biasing force of the first biasing member.

[0024] A wheeled childcare apparatus according to another aspect of the present invention includes a body frame including front legs, rear legs, and a push bar that can be switched between a rear-facing position and a forward-facing position; a front caster mechanism that has front caster holding members attached to the lower ends of the front legs and front caster rotation members that are rotatably held by the front caster holding members about rotation axes that extend vertically and support the front wheels, thereby enabling the front wheels to turn; a rear caster mechanism that has rear caster holding members attached to the lower ends of the rear legs and rear caster rotation members that are rotatably held by the rear caster holding members about rotation axes that extend vertically and support the rear wheels, thereby enabling the rear wheels to turn; a front caster lock member attached to the front caster mechanism that restricts rotation of the front caster rotation member in a locked position and allows rotation of the front caster rotation member in an unlocked position; and a front caster lock member attached to the rear caster mechanism that locks when in a locked position and allows rotation of the front caster rotation member in an unlocked position. a rear-wheel caster locking member that restricts the rotation of the rear-wheel caster pivoting member in a locked position and allows the rotation of the rear-wheel caster pivoting member in an unlocked position; a front-wheel side displacement member that is provided on the vehicle frame and connected to the front-wheel caster locking member via a connecting member and displaces between a first position corresponding to the locked position of the front-wheel caster locking member and a second position corresponding to the unlocked position of the front-wheel caster locking member; a rear-wheel side displacement member that is provided on the vehicle frame at a distance from the front-wheel side displacement member and connected to the rear-wheel caster locking member via a connecting member and displaces between a first position corresponding to the locked position of the rear-wheel caster locking member and a second position corresponding to the unlocked position of the rear-wheel caster locking member; and an operating mechanism that is provided on the push rod and can be operated to switch the front-wheel caster locking member and the rear-wheel caster locking member from the locked position to the unlocked position.

[0025] Preferably, the wheeled childcare equipment further includes a first front wheel side biasing member that biases the front wheel side displacement member to the second position, and a first rear wheel side biasing member that biases the rear wheel side displacement member to the second position.

[0026] Preferably, the operating mechanism is operable to switch the front wheel side displacement member and the rear wheel side displacement member from a first position to a second position, and includes an operating member and a drive member connected to the operating member and switched between a first state and a second state by the operating force of the operating member, wherein the drive member in the first state brings the front wheel side displacement member or the rear wheel side displacement member to the first position, and the drive member in the second state brings the front wheel side displacement member or the rear wheel side displacement member to the second position.

[0027] Preferably, the operating mechanism further includes a second biasing member that biases the drive member toward the first state, and the biasing force of the second biasing member is greater than the biasing forces of the first front-wheel side biasing member and the first rear-wheel side biasing member.

[0028] Preferably, the wheeled childcare equipment further includes a third front-wheel side biasing member that biases the front-wheel caster locking member toward the locked position, and a third rear-wheel side biasing member that biases the rear-wheel caster locking member toward the locked position, the biasing force of the third front-wheel side biasing member being smaller than the biasing force of the first front-wheel side biasing member, and the biasing force of the third rear-wheel side biasing member being smaller than the biasing force of the first front-wheel side biasing member. [Effects of the Invention]

[0029] The childcare implement with wheels of the present invention can have a simple structure. [Brief explanation of the drawings]

[0030] [Figure 1] 1A and 1B are side views of a stroller according to a first embodiment of the present invention, in which (A) shows a state in which the push bar is in a rear position, and (B) shows a state in which the push bar is in a forward position. [Figure 2] 1 is a schematic diagram showing the internal structure of the stroller according to the first embodiment of the present invention, showing a state in which the stroller is being pushed from behind and the operating mechanism is not being operated. [Figure 3] 1 is a schematic diagram showing the internal structure of the stroller according to the first embodiment of the present invention, showing a state in which the operating mechanism is operated while the stroller is being pushed from behind. [Figure 4]1 is a schematic diagram showing the internal structure of the stroller according to the first embodiment of the present invention, showing a state in which the stroller is in a face-to-face pushing state and the operating mechanism is not being operated. [Figure 5] 1 is a schematic diagram showing the internal structure of the stroller according to the first embodiment of the present invention, showing the state in which the operating mechanism is operated in the face-to-face pushing state. [Figure 6] 10A and 10B are side views showing a modified example of the first embodiment, in which (A) shows a back-pressed state and (B) shows a front-pressed state. [Figure 7] 1A and 1B are perspective views showing a part of the stroller in a rear-pushing state, in which (A) shows the state in which the operating mechanism is not operated, and (B) shows the state in which the operating mechanism is operated. [Figure 8] 1A and 1B are perspective views showing a part of the stroller in a face-to-face pushing state, in which (A) shows the state in which the operating mechanism is not operated, and (B) shows the state in which the operating mechanism is operated. [Figure 9] 10A and 10B are diagrams showing modified examples of the caster locking member, in which (A) shows the unlocked state and (B) shows the locked state. [Figure 10] FIG. 10 is a schematic diagram showing the internal structure of a stroller according to a second embodiment of the present invention, showing a state in which the rear side is being pressed and the operating mechanism is not being operated. [Figure 11] FIG. 10 is a schematic diagram showing the internal structure of a stroller according to a second embodiment of the present invention, showing a state in which the operating mechanism is operated while the stroller is being pushed from behind. [Figure 12] 10A and 10B are schematic diagrams showing the internal structure of a stroller according to embodiment 3 of the present invention, in a back-pushing state, where (A) shows the state in which the operating mechanism is not operated, and (B) shows the state in which the operating mechanism is operated. [Figure 13] 10A and 10B are diagrams illustrating an internal structure of a front wheel side displacement member. [Figure 14] 10A and 10B are schematic diagrams showing the internal structure of a stroller according to embodiment 3 of the present invention, in a face-to-face pushing state, where (A) shows the state in which the operating mechanism is not operated, and (B) shows the state in which the operating mechanism is operated. [Figure 15]14A and 14B are diagrams showing the movement of the front-wheel-side displacement member corresponding to FIG. 13, in which (A) shows a state in which the operating mechanism is not operated, and (B) shows a state in which the operating mechanism is operated. [Figure 16] 10A and 10B are schematic diagrams showing the internal structure of a stroller according to embodiment 4 of the present invention, in a back-pushing state, where (A) shows the state in which the operating mechanism is not operated, and (B) shows the state in which the operating mechanism is operated. [Figure 17] 10A and 10B are schematic diagrams showing the internal structure of a stroller according to embodiment 4 of the present invention, in a face-to-face pushing state, where (A) shows the state in which the operating mechanism is not operated, and (B) shows the state in which the operating mechanism is operated. [Figure 18] 10A and 10B are schematic diagrams showing the internal structure of a stroller according to embodiment 5 of the present invention, in a back-pushing state, where (A) shows the state in which the operating mechanism is not operated, and (B) shows the state in which the operating mechanism is operated. [Figure 19] FIG. 10 is a schematic diagram showing the internal structure of a stroller according to a fifth embodiment of the present invention, showing a state in which the stroller is pushed face-to-face and the operating mechanism is not being operated. [Figure 20] 20A and 20B are diagrams showing the movement of an inter-wheel displacement member corresponding to FIG. 19, in which (A) shows a state in which the operating mechanism is not operated, and (B) shows a state in which the operating mechanism is operated. DETAILED DESCRIPTION OF THE INVENTION

[0031] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the accompanying drawings, in which like reference numerals denote like or corresponding parts and will not be described repeatedly.

[0032] <First Embodiment> (For each configuration) An overview of a stroller 1 according to this embodiment will be described with reference to Figures 1(A) and 1(B). Figure 1(A) shows the state in which the push bar is in the rear-pushing position. Figure 1(B) shows the state in which the push bar is in the rear-pushing position. To facilitate understanding of the invention, the drawings mainly show the body frame of the stroller with back-to-front facing interchangeable, and do not include illustrations of the infant seat and other components. In the following description, the front-to-rear direction corresponds to the front-to-rear direction of the stroller, and the left-to-right direction corresponds to the left-to-right direction when viewed from the front of the stroller.

[0033] The stroller 1 of this embodiment comprises a body frame 10, which includes a pair of front legs 11, a pair of rear legs 13, armrests 15, armrest support members 17, a seat support member 18, a backrest support member 19, and a push bar 20. The body frame 10, excluding the seat support member 18, the backrest support member 19, and the push bar 20, is provided on the left and right, spaced apart in the width direction (vehicle width direction), and forms a pair.

[0034] A front caster mechanism 30 is provided at the lower end of each front leg 11 extending in the vertical direction, and a front wheel 12 is provided via the front caster mechanism 30. A rear caster mechanism 40 is provided at the lower end of each rear leg 13 extending in the vertical direction behind each front leg 11, and a rear wheel 14 is provided via the rear caster mechanism 40. The front caster mechanism 30 and the rear caster mechanism 40 will be described later.

[0035] The upper ends of the front legs 11 are rotatably connected to the front end of an armrest 15 extending in the front-to-rear direction of the stroller 1. The upper ends of the rear legs 13 are rotatably connected to the front end region of the armrest 15 behind the upper ends of the front legs 11. As shown in FIG. 1(B), the rear end of the armrest 15 is rotatably connected to the upper end of an armrest support member 17 extending in the vertical direction via a rotation shaft 28. Specifically, the rear end of the armrest 15 and the upper end of the armrest support member 17 are also connected to a hood rib 29 via the rotation shaft 28.

[0036] A seat support member 18 is disposed below the armrest 15. The front end of the seat support member 18 is connected to the center of the pair of front legs 11. The rear end of the seat support member 18 is rotatably connected to the lower end of the push rod 20, the upper end of the reversing bracket 27, and the lower end of the armrest support member 17 via a swing shaft 21.

[0037] The rear end of the seat support member 18 is rotatably connected to the lower end of the backrest support member 19 at a position different from the swing shaft 21. The seat support member 18 supports the seat portion of the baby from below, and the backrest support member 19 supports the backrest portion of the baby from below. Although not shown, a hammock is hung between the seat support member 18 and the backrest support member 19, and a cushion is attached to the hammock. As a result, a seat surface that forms the seat portion is formed on the seat support member 18, and the seat support member 18 supports the seat surface from below.

[0038] The push bar 20 is, for example, in an inverted U-shape and is provided via a swing shaft 21 so as to be swingable in the front-to-rear direction relative to the body frame 10, and can be switched between a rear-facing position (FIG. 1(A)) and a front-facing position (FIG. 1(B)). Specifically, the lower end of the push bar 20 is rotatably connected via the swing shaft 21 to the lower end of an armrest support member 17 (described later). The swing shaft 21 is disposed in a position adjacent to the rear leg 13. An operating mechanism 22 is provided at the upper end of the push bar 20. The operating mechanism 22 will also be described later.

[0039] As shown in Fig. 1(B), the armrest support member 17 is a member that extends vertically. The upper end of the armrest support member 17 is rotatably connected to the rear end of the armrest 15 and two hood ribs 29 via a pivot shaft 28. The lower end of the armrest support member 17 is rotatably connected to the lower end of the push rod 20, the upper end of the reversing bracket 27, and the rear end of the seat support member 18 via a swing shaft 21. Although not shown, a plurality of auxiliary hood ribs are arranged between the hood ribs 29, and a hood cloth is stretched between the hood ribs 29.

[0040] The lower end of the armrest support member 17 is provided so as to be switchable between a position where it is locked to the rear leg 13 and a position where it is unlocked. The position where the armrest support member 17 is locked to the rear leg 13 is the traveling state shown in Figures 1(A) and 1(B), where the lower end of the armrest support member 17 abuts against the center of the rear leg 13.

[0041] The position at which the armrest support member 17 is unlocked from the rear legs 13 is the folded state (not shown), where the lower end of the armrest support member 17 abuts against the lower end of the rear legs 13. Specifically, a locking section (not shown) that can be locked to the rear legs 13 is provided at the lower end of the armrest support member 17, and unlocking the locking section releases the lock between the rear legs 13 and the armrest support member 17. With this configuration, the stroller 1 can be folded. Note that a locking section that can be locked to the rear legs 13 may be provided at the upper end of the reversing bracket 27.

[0042] In the stroller 1 described above, both the front wheels 12 and the rear wheels 14 are caster wheels, and in the normal state where the operating mechanism 22 is not operated, the wheel on the front side in the direction of travel is caster-free (can be turned), and the wheel on the rear side in the direction of travel is caster-locked (cannot be turned), but in the operating state where the operating mechanism 22 is operated, both wheels 12, 14 become caster-free (can be turned). The state where both wheels 12, 14 can be turned is also called the "drift state."

[0043] 2 to 5, the structure for caster-free and caster-locking the wheels 12, 14 will be described in detail. For ease of understanding, Figs. 2 to 5 show an enlarged view of the internal structure near the wheels 12, 14. For ease of understanding, in the following figures, the displacement members 52, 56 and the drive member 24 are indicated by light ink, and the connecting members 25, 51, 55 are indicated by lines (dashed lines, one-dot chain lines, two-dot chain lines) that are different from the solid lines.

[0044] As described above, the front caster mechanism 30 enables the front wheels 12 to turn. The front caster mechanism 30 is provided at the lower end of the front leg 11 and includes a front caster holding member 31 fixed to the lower end of the front leg 11, and a front caster pivoting member 32 disposed below the front caster holding member 31. The front caster pivoting member 32 is held by the front caster holding member 31 so as to be rotatable about a pivot axis extending in the vertical direction, and supports the front wheels 12.

[0045] The rear caster mechanism 40 enables the rear wheels 14 to turn. Similar to the front caster mechanism 30, the rear caster mechanism 40 has a rear caster holding member 41 fixed to the lower end of the rear leg 13, and a rear caster pivoting member 42 that is held by the rear caster holding member 41 so as to be rotatable about a pivot axis that extends in the vertical direction and that pivotally supports the rear wheels 14, thereby enabling the rear wheels 14 to turn. The rear caster pivoting member 42 is held by the rear caster holding member 41 so as to be rotatable about a pivot axis that extends in the vertical direction and that pivotally supports the rear wheels 14.

[0046] As shown in FIG. 2, the front caster retaining member 31 is provided with a first front wheel hole 33, a front caster locking member 35, and a third front wheel biasing member 36. The front caster pivoting member 32 is provided with a second front wheel hole 34, which is a vertically elongated hole connected to the first front wheel hole 33. The front caster locking member 35 can be displaced to either a lower locked position or an upper unlocked position. In the locked position, the front caster locking member 35 protrudes from the front caster retaining member 31 into the second front wheel hole 34 and engages with the front caster pivoting member 32, as shown in FIG. 4. This prevents the front caster pivoting member 32 from pivoting about the pivot axis.

[0047] 2 and 3, in the unlocked position, the front caster locking member 35 is housed in the first front wheel hole 33 of the front caster holding member 31 and disengages from the second front wheel hole 34 of the front caster pivoting member 32. This allows the front caster locking member 35 to rotate about the pivot axis. The third front wheel biasing member 36 is, for example, a spring, and biases the front caster locking member 35 downward to bring it into the locked position. Note that, as an example, the third front wheel biasing member 36 is disposed between the first front wheel hole 33 and the upper end of the front caster locking member 35, but the location and type of spring are not limited to those shown in the drawings as long as it biases the front caster locking member 35 into the locked position.

[0048] As shown in the figure, the rear caster retaining member 41 is provided with a first rear wheel hole 43, a rear caster locking member 45, and a third rear wheel biasing member 46. The rear caster pivoting member 42 is provided with a second rear wheel hole 44, which is an elongated hole extending vertically and connected to the first rear wheel hole 43. The rear caster locking member 45 can be displaced to either a lower locked position or an upper unlocked position. In the locked position, the rear caster locking member 45 protrudes from the rear caster retaining member 41 to the second rear wheel hole 44 as shown in FIG. 2 and engages with the rear caster pivoting member 42. This allows the rear caster locking member 45 to restrict the rear caster pivoting member 42 from pivoting about the pivot axis.

[0049] In addition, in the unlocked position, the rear caster locking member 45 is housed in the first rear wheel hole 43 of the rear caster holding member 41 as shown in Figures 4 and 5, and is disengaged from the rear caster pivoting member 42. This allows the rear caster locking member 45 to rotate about the rotation axis of the rear caster pivoting member 42. The third rear wheel biasing member 46 is, for example, a spring, and biases the rear caster locking member 45 downward to bring it into the locked position. Note that, as an example, the third rear wheel biasing member 46 is disposed between the first rear wheel hole 43 and the upper end of the rear caster locking member 45, but the location and type of spring are not limited to those shown in the figures as long as it biases the rear caster locking member 45 into the locked position.

[0050] A front wheel connecting member 51 and a rear wheel connecting member 55 are displaceably mounted on the body frame 10. The front wheel connecting member 51 and the rear wheel connecting member 55 are long, flexible metal members, such as wire. The front wheel connecting member 51 is passed through the pipe-shaped front leg 11. One end of the front wheel connecting member 51 is connected to the front caster lock member 35 inside the front caster holding member 31. The other end of the front wheel connecting member 51 is connected to the front-wheel-side displacement member 52 inside the front leg 11.

[0051] 2, the rear wheel connecting member 55 is passed through the pipe-shaped rear leg 13, the inversion bracket 27, and the armrest support member 17 in that order. One end of the rear wheel connecting member 55 is connected to the rear caster lock member 45 inside the rear caster holding member 41. The other end of the rear wheel connecting member 55 is connected to the rear wheel-side displacement member 56 inside the rear leg 13.

[0052] As described above, the front-wheel-side displacement member 52 is connected to the front caster locking member 35 via the front-wheel connecting member 51. The front-wheel-side displacement member 52 is displaced between a first position corresponding to the lock position (lower position: Figure 4) of the front caster locking member 35 and a second position corresponding to the unlock position (upper position: Figure 2) of the front caster locking member 35 in accordance with the switching of the push bar 20. The front-wheel-side displacement member 52 is also displaced between the first and second positions by operating the above-mentioned operating mechanism 22 when in the facing position.

[0053] The front-wheel-side displacement member 52 is provided so as to be movable up and down along the body frame 10, specifically at least along the front leg 11. The front-wheel-side displacement member 52 is a member that moves up and down along the outer periphery of the pipe-shaped front leg 11, but the specific shape of the front-wheel-side displacement member 52 is not limited, and it is sufficient if it is connected to at least the front-wheel connecting member 51 and transmits its displacement to the front-wheel caster lock member 35.

[0054] The front-wheel-side displacement member 52 is biased to the second position by the front-wheel-side first biasing member 53. As a result, the front-wheel-side displacement member 52 brings the front caster locking member 35 to the unlocked position (upper position: Figure 2). The front-wheel-side first biasing member 53 is, for example, a spring. The biasing force of the front-wheel-side first biasing member 53 is greater than the biasing force of the front-wheel third biasing member 36 of the front caster mechanism 30. As a result, as shown in Figures 2 and 3, when the drive member 24 of the operation mechanism 22 is not in contact with the front-wheel-side displacement member 52, the biasing force of the front-wheel-side first biasing member 53 positions the front caster locking member 35 in the unlocked position (upper position: Figure 2).

[0055] As described above, the rear-wheel-side displacement member 56 is connected to the rear-wheel caster locking member 45 via the rear-wheel connecting member 55. The rear-wheel-side displacement member 56 is displaced between a first position corresponding to the lock position (upper position: Figure 2) of the rear-wheel caster locking member 45 and a second position corresponding to the unlock position (lower position: Figure 3) of the rear-wheel caster locking member 45 in accordance with the switching of the push bar 20. The rear-wheel-side displacement member 56 is also displaced between the first position and the second position by operating the operating member 23 described above.

[0056] As shown in FIG. 4 , the rear-wheel-side displacement member 56 is provided on the body frame 10, specifically, along the armrest support member 17, so as to be movable up and down. The rear-wheel-side displacement member 56 is a member that moves up and down along the outer periphery of the pipe-shaped armrest support member 17, but the specific shape of the rear-wheel-side displacement member 56 is not limited, as long as it is connected to at least the rear-wheel connecting member 55 and transmits its displacement to the rear-wheel caster lock member 45. The rear-wheel-side displacement member 56 is provided on the body frame 10, separated from the front-wheel-side displacement member 53. Specifically, the front-wheel-side displacement member 53 is provided on the front leg 11, and the rear-wheel-side displacement member 52 is provided on the armrest support member 17 on the rear leg 13 side, so that they are substantially spaced apart, but the front-wheel-side displacement member 53 and the rear-wheel-side displacement member 56 do not have to be connected to each other and may be adjacent to or abutting against each other.

[0057] The rear-wheel-side displacement member 56 is biased to the second position (upper position) by the rear-wheel-side first biasing member 57. As a result, the rear-wheel-side displacement member 56 brings the rear-wheel caster locking member 45 to the unlocked position (upper position: Figure 3). The rear-wheel-side first biasing member 57 is, for example, a spring. The biasing force of the rear-wheel-side first biasing member 57 is greater than the biasing force of the rear-wheel third biasing member 46 of the rear caster mechanism 40. As a result, as shown in Figures 4 and 5, when the drive member 24 of the operation mechanism 22 is not in contact with the rear-wheel-side displacement member 56, the biasing force of the rear-wheel-side first biasing member 57 pulls up the rear-wheel connecting member 55, and the rear-wheel caster locking member 45 is positioned in the unlocked position (upper position: Figure 3).

[0058] As described above, the operating mechanism 22 is provided above the push rod 20, which can be switched between a rear position (FIG. 1(A)) and a facing position (FIG. 1(B)). The operating mechanism 22 can operate the front-wheel-side displacement member 52 and the rear-wheel-side displacement member 56 from a first position to a second position. Specifically, when the operating mechanism 22 is in the rear position, it can operate the rear-wheel-side displacement member 56, and when it is in the facing position, it can operate the front-wheel-side displacement member 52. Here, being operable is intended to include not only direct operation by being connected to one another, but also indirect operation by acting on the other.

[0059] The operating mechanism 22 includes an operating member 23 and a drive member 24 connected to the operating member 23 and switched by the operating force of the operating member 23. The operating member 23 is provided above the push bar 20 and is, for example, a button that can be pressed or a lever that can be pulled up. The operating member 23 is connected to the drive member 24 by an operating connecting member 25. The drive member 24 can be switched between a first state (downward state: FIGS. 3 and 5) and a second state (upward state: FIGS. 2 and 4). The drive member 24 is biased to the first state (downward state) by a second biasing member 26. The second biasing member 26 is, for example, a spring. The biasing force of the second biasing member 26 is greater than the biasing force of the rear-wheel-side first biasing member 57 and the front-wheel-side first biasing member 53. From the above, the following relationship is established for the biasing forces of the biasing members provided in the stroller. (front wheel third biasing member 36 = rear wheel third biasing member 46) < (front wheel side first biasing member 53 = rear wheel side first biasing member 57) < second biasing member 26

[0060] When the drive member 24 is in the rear position shown in FIG. 2 , it brings the rear-wheel-side displacement member 56 to the first position (downward position). As described above, the biasing force of the second biasing member 26 of the operation mechanism 22 is greater than the biasing force of the first rear-wheel-side biasing member 57. Therefore, the drive member 24 in the first state blocks the biasing force of the first rear-wheel-side biasing member 57 acting on the rear-wheel-side displacement member 56. In other words, the biasing force of the first rear-wheel biasing member 57 acting on the rear-wheel-side displacement member 56 is canceled out by the biasing force of the second biasing member 26 acting on the drive member 24, and the rear-wheel-side displacement member 56 moves downward together with the drive member 24 due to the biasing force of the second biasing member 26 of the drive member 24, and the rear-wheel caster lock member 45 is positioned in the locked position.

[0061] When the drive member 24 is in the rear position shown in FIG. 3 , the drive member 24 in the second state brings the rear-wheel-side displacement member 56 to the second position (upper position). As described above, the biasing force of the second biasing member 26 of the operation mechanism 22 is greater than the biasing force of the first rear-wheel-side biasing member 57. However, unless the drive member 24 abuts against the rear-wheel-side displacement member 56, the biasing force of the second biasing member 26 of the drive member 24, which blocks the biasing force of the first rear-wheel-side biasing member 57 acting on the rear-wheel-side displacement member 56, is not exerted. Therefore, the drive member 24 in the second state enables the biasing force of the first rear-wheel-side biasing member 57 acting on the rear-wheel-side displacement member 56. In other words, by operating the operating member 23 to move the drive member 24 upward and thereby releasing the biasing force of the second biasing member 26, the rear-wheel-side displacement member 56 moves upward due to the biasing force of the rear-wheel-side first biasing member 57, and the rear-wheel caster locking member 45 is positioned in the unlocked position. In this way, the drive member 24 is not directly connected to the rear-wheel-side displacement member 56, but is indirectly operated by the operating mechanism 22.

[0062] (About operation) With reference to Figures 2 to 5, the operation of restricting or allowing rotation of the caster mechanisms 30, 40 of the stroller 1 according to this embodiment will be described. Figures 2 and 3 show the push bar 20 in the rear position, with Figure 2 showing a state where the operating mechanism is not operated and Figure 3 showing a state where the operating mechanism is operated. Figures 4 and 5 show the push bar 20 in the front-facing position, with Figure 4 showing a state where the operating mechanism is not operated and Figure 5 showing a state where the operating mechanism is operated.

[0063] First, with reference to Figures 2 and 3, the operation when the push bar 20 is in the rear position will be described. As shown in Figure 2, when the push bar 20 is in the rear position, the front caster mechanism 30 is rotatable about its axis of rotation, while the rear caster mechanism 40 is prohibited from rotating about its axis of rotation. Specifically, in the front caster mechanism 30, the front wheel displacement member 52 is urged upward by the front wheel first urging member 53, so the front caster locking member 35 is in the unlocked position (upper position).

[0064] In the rear-wheel caster mechanism 40, the drive member 24 of the operating mechanism 22 provided on the push rod 20 and the rear-wheel-side displacement member 56 provided on the armrest support member 17 are in contact in the vertical direction. Because the biasing force of the second biasing member 26 acting on the drive member 24 is greater than the biasing force of the first rear-wheel-side biasing member 57 acting on the rear-wheel-side displacement member 56, the drive member 24 blocks the biasing force of the first rear-wheel-side biasing member 57 acting on the rear-wheel-side displacement member 56. As a result, the rear-wheel-side displacement member 56 is biased downward by the biasing force of the second biasing member 26 of the drive member 24, and the rear-wheel caster locking member 45 is positioned in the locked position (downward position).

[0065] As shown in Figure 3, when the push rod 20 is in the rear position, the operating member 23 is operated to enable not only the front caster mechanism 30 but also the rear caster mechanism 40 to rotate about the rotation axis and enter the drift state. Specifically, the operating member 23 is operated to pull up the operating coupling member 25. This switches the drive member 24 to the second state, and the rear wheel displacement member 56 is moved upward by the rear wheel first biasing member 57, which in turn moves the rear caster locking member 45 to the unlocked position (upper position). By operating the operating mechanism 22 in this way, not only the front caster mechanism 30 but also the rear caster mechanism 40 becomes rotatable about the rotation axis, thereby entering the drift state.

[0066] Next, the operation when the push bar 20 is in the facing position will be described with reference to Figures 4 and 5. As shown in Figure 4, when the push bar 20 is in the facing position, the rear caster mechanism 40 is rotatable about its axis of rotation, while the front caster mechanism 30 is prohibited from rotating about its axis of rotation.

[0067] Specifically, in the front-wheel caster mechanism 30, the front-wheel-side displacement member 52 is urged upward by the front-wheel-side first biasing member 53, but the front-wheel-side displacement member 52 abuts against the drive member 24 provided on the push rod 20 displaced to the facing position. Because the biasing force of the second biasing member 26 acting on the drive member 24 is greater than the biasing force of the front-leg-side first biasing member 53 acting on the front-wheel-side displacement member 52, the drive member 24 blocks the biasing force of the front-leg-side first biasing member 53 acting on the front-wheel-side displacement member 52. As a result, the front-wheel-side displacement member 52 is urged downward by the biasing force of the second biasing member 26 of the drive member 24, and the front-wheel caster locking member 35 is positioned in the locked position (downward position).

[0068] In the rear-wheel caster mechanism 40, because the push rod 20 has been displaced to the facing position, the rear-wheel-side displacement member 56 provided on the armrest support member 17 is not in contact with the drive member 24 of the operation mechanism 22, i.e., is in a free state. The rear-wheel-side displacement member 56 is urged upward by the rear-wheel-side first urging member 57, and the rear-wheel caster locking member 45 is positioned in the unlocked position (upper position).

[0069] When the push rod 20 is in the facing position, the operating member 23 is operated to enable not only the rear caster mechanism 40 but also the front caster mechanism 30 to rotate about the rotation axis to enter the drift state. As shown in FIG. 5, the operating member 23 is operated to pull up the operating connecting member 25. This switches the drive member 24 to the second state, and the front wheel displacement member 52 is moved upward by the front wheel first biasing member 53, which in turn moves the front caster locking member 35 to the unlocked position (upper position). By operating the operating mechanism 22 in this way, not only the rear caster mechanism 40 but also the front caster mechanism 30 becomes rotatable about the rotation axis, thereby entering the drift state.

[0070] (About the effects) In this way, the stroller 1 of this embodiment is able to restrict and allow the rotation of the caster mechanisms 30, 40 using only the caster mechanisms 30, 40, the displacement members 52, 56 connected to them via connecting members 51, 55, and the operating mechanism 22 that can operate the displacement members 52, 56, thereby reducing the number of parts and achieving a simple structure.

[0071] In conventional strollers, if the rotation of the caster locking mechanisms of the front and rear wheels was to be simultaneously restricted and permitted, a wire had to be provided to connect the caster locking mechanisms of the front and rear wheels. In contrast, stroller 1 of this embodiment does not require a wire to connect caster locking members 35, 45 of front wheel 12 and rear wheel 14. Stroller 1 of this embodiment can have a simple structure, also from the perspective of reducing the amount of wire required to be handled.

[0072] Furthermore, in conventional strollers, the caster locking mechanism, which restricts the rotation of the front and rear wheels, is directly connected by a wire to an operating member attached to the push rod, so the force of operating the operating member is transmitted directly to the caster locking mechanism. Therefore, when the caster locking member is in the locked position and abutting the wall of the hole, operating the operating member to move the caster locking mechanism to the unlocked position creates resistance between the caster locking member and the wall of the hole. This resistance is transmitted directly to the operating member via the wire, so the caster locking mechanism cannot be unlocked even when the operating member is operated, resulting in a poor user experience. Furthermore, if the resistance is strong, the wire may break, leading to malfunction.

[0073] In contrast, in the stroller 1 of this embodiment, the caster locking mechanisms 30, 40 are not connected to the operating mechanism 22, so the operating force of the operating mechanism 22 is not directly transmitted to the caster locking mechanisms 30, 40. Specifically, the operating mechanism 22 can be operated to exert the biasing force of the first biasing members 53, 57 that bias the displacement members 53, 56. As a result, even if resistance occurs between the caster locking mechanisms 30, 40 and the wall surfaces of the holes 33, 34, 43, 44, the biasing force of the first biasing members 53, 57 always biases the caster locking mechanisms 30, 40 upward with a constant force. Therefore, by operating the operating mechanism 22 to displace the displacement member to the upward position, the caster locking mechanisms 30, 40 can be placed in the unlocked position when the positions of the caster locking mechanisms 30, 40 and the holes 33, 34, 43, 44 are aligned. In this way, the stroller 1 of this embodiment can improve the operability of the operation that allows the caster mechanisms 30, 40 to rotate, and can also prevent breakdowns in parts.

[0074] (Regarding variants) 6 to 8, a modified example of the stroller according to the present embodiment 1 will be described. The front wheel side displacement member 52A in the above embodiment is provided on the front leg 11, but it may also be provided on the rear leg 13.

[0075] The front-wheel-side displacement member 52A of the stroller 1A is provided above the rear legs 13 and protrudes outward in the width direction of the stroller 1 (toward the push bar 20). As shown in FIG. 7(A), the front-wheel-side displacement member 52A includes a main body portion 52aA and a protrusion portion 52bA that protrudes upward from the main body portion 52aA. The front-wheel-side displacement member 52A is connected to a front-wheel connecting member 51A. The front-wheel connecting member 51A passes through the interiors of the front legs 11 and then the rear legs 13, in that order.

[0076] Similar to the above embodiment, the rear-wheel-side displacement member 56A is provided on the armrest support member 17 and is movable up and down. Like the rear-wheel-side displacement member 56A, the rear-wheel-side displacement member 56A is provided to protrude in the width direction of the stroller 1. Specifically, the rear-wheel-side displacement member 56A includes a main body portion 56aA that is slidable relative to the armrest support member 17, and a hook portion 56bA that protrudes outward in the width direction from the main body portion 56aA. The protrusion portion 52bA of the front-wheel-side displacement member 52A and the hook portion 56bA of the rear-wheel-side displacement member 56A are arranged at positions where the linear distances from the swing shaft 21 of the push rod 20 are approximately the same.

[0077] The drive member 24A provided on the push rod 20 includes a main body portion 24aA that is slidable relative to the push rod 20 and a hook portion 24bA that protrudes widthwise inward from the main body portion 24aA. In the rear position shown in FIGS. 7A and 7B, the hook portion 24bA of the drive member 24 abuts against the hook portion 56bA of the rear-wheel-side displacement member 56A at the top and bottom. In the facing position shown in FIGS. 8A and 8B, the hook portion 24bA of the drive member 24A abuts against the protruding portion 52bA of the front-wheel-side displacement member 52A at the top and bottom. In this manner, by exposing the displacement members 52A and 56A to the outside of the body frame 10 and protruding toward the widthwise outward (push rod 20) side, and by having the drive member 24A protruding toward the widthwise inward (body frame 10) side, the displacement members 52A and 56A can be easily brought into contact with the drive member 24A.

[0078] A modified example of the caster locking member in the first embodiment will be described with reference to Figure 9. The caster locking members 35 and 45 in the above-described embodiment are vertically elongated rod-shaped members that are not exposed to the outside, but they may be exposed to the outside as shown in Figure 9. Note that the front caster locking member 35 and the rear caster locking member 45 have the same shape, so only the rear caster locking member 45B will be described.

[0079] As shown in FIG. 9, the rear caster locking member 45B of the stroller 1B is attached to the outer periphery of the rear caster mechanism 40 and is pivotally supported, for example, by the rear caster holding member 41. Although not shown, the rear caster locking member 45B is connected to the rear wheel connecting member 55 described in the above embodiment. The rear caster locking member 45B includes a main body 45aB that extends in an arc along the outer periphery of the rear caster holding member 41 and a protrusion 45bB that protrudes downward from the main body 45aB. The main body 45aB is rotatable up and down around the axle 45cB, and as shown in FIG. 9(B), it rotates downward and fits into the recess 44B of the rear caster pivoting member 42, thereby locking the rear caster locking member 45B.

[0080] <Embodiment 2> The configuration and operation of a stroller 1C according to embodiment 2 will be described with reference to Figures 10 and 11. Stroller 1C of this embodiment has the same basic configuration as embodiment 1, but differs in that push bar 20 is fixed at the rear position and displacement members are provided only on the rear wheel 14 side. Only the differences from the configuration shown in embodiment 1 will be described in detail.

[0081] (For each configuration) In the stroller 1C of this embodiment, both the front wheels 12 and the rear wheels 14 are caster wheels, but only the rear wheels 14 are provided with caster lock members 45 to restrict rotation about the turning axis. The stroller 1C shown as an example in Figure 10 is foldable.

[0082] 10 and 11 includes at least the rear wheel caster mechanism 40, rear wheel caster locking member 45, rear wheel displacement member 56, rear wheel first biasing member 57, and drive member 24 provided on push rod 20, all of which are described in connection with stroller 1 of embodiment 1. Drive member 24 of this embodiment is operated by operating mechanism 22, as in embodiment 1.

[0083] (About operation) 10, the drive member 24 of the operating mechanism 22 provided on the push rod 20 and the rear-wheel-side displacement member 56 provided on the armrest support member 17 are in contact with each other in the vertical direction. Because the biasing force of the second biasing member 26 acting on the drive member 24 is greater than the biasing force of the first rear-wheel-side biasing member 57 acting on the rear-wheel-side displacement member 56, the drive member 24 blocks the biasing force of the first rear-wheel-side biasing member 57 acting on the rear-wheel-side displacement member 56. As a result, the rear-wheel-side displacement member 56 is biased downward by the biasing force of the second biasing member 26 of the drive member 24, and the rear-wheel caster lock member 45 is positioned in the locked position (downward position).

[0084] As shown in FIG. 11 , when the push rod 20 is in the rear position, the operating member 23 is operated to make the rear caster mechanism 40 rotatable about the rotation axis and set it in a drift state. Specifically, the operating member 23 is operated to pull up the operating connecting member 25. As a result, the rear wheel displacement member 56 of the drive member 24 is moved upward by the rear wheel first biasing member 57, the biasing force of the second biasing member 26 is neutralized, and the rear wheel displacement member 56 is moved upward by the biasing force of the rear wheel first biasing member 57, the rear wheel connecting member 55 is pulled up, and the rear caster locking member 45 moves to the unlocked position (upper position). In this way, by operating the operating mechanism 22, the rear caster mechanism 40 can be made rotatable about the rotation axis.

[0085] (Regarding variants) In the above embodiment, the driving member 24 is described as constituting part of the operation mechanism 22 and being operated by the operation member 23, but the driving member 24 does not have to be operated by the operation member 23 as long as it switches the rear wheel-side displacement member 56 from the first position to the second position. For example, the driving member 24 may be able to move up and down directly along the push rod 20, and may be manually moved upward only when it is desired to make the rear wheel caster mechanism 40 rotatable about the rotation axis.

[0086] Although the stroller 1C of this embodiment has been described as being foldable with the push bar 20 fixed in the rear-facing position, the push bar 20 may be switchable between the forward-facing position and the rear-facing position, or may not be foldable. In this case, since a non-foldable stroller does not have the reversing bracket 27, the rear wheel connecting member 55 passes through the rear legs 13 and the lower end of the push bar 20 in that order, and the rear wheel-side displacement member 56 may be provided at the lower end of the push bar 20.

[0087] Furthermore, in the stroller 1C of this embodiment, the rear wheel caster locking member 45, the rear wheel displacement member 56, and the first rear wheel biasing member 57 are provided only on the rear wheels 14, but it is also possible to not provide all of these components on the rear legs 13, and instead place only the front wheel caster locking member 35, the front wheel displacement member 52, and the first front wheel biasing member 53 on the front legs 11, so that the stroller can be put into a drift state only when the push bar 20 is switched to the facing position.

[0088] <Third Embodiment> The configuration and operation of a stroller 1D according to embodiment 3 will be described with reference to Figures 12 to 15. The stroller 1D of this embodiment has the same basic configuration as that of embodiment 1, but a major difference is that it is provided with an inter-wheel connecting member 58D that connects the front caster locking member 35 and the rear caster locking member 45. Only the differences from the configuration shown in embodiment 1 will be described in detail.

[0089] (For each configuration) The stroller 1D of this embodiment is provided with an inter-wheel connecting member 58D that connects the front caster locking member 35 and the rear caster locking member 45. The inter-wheel connecting member 58D passes through the front leg 11 and the rear leg 13 in that order. As a result, not only the front wheel connecting member 51 that connects to the front wheel side displacement member 52D but also one end of the inter-wheel connecting member 58D are connected to the front caster locking member 35. Not only the rear wheel connecting member 55 that connects to the rear wheel side displacement member 56D but also the other end of the inter-wheel connecting member 58D are connected to the rear wheel caster locking member 45. Like the front wheel connecting member 51 and the rear wheel connecting member 55, the inter-wheel connecting member 58D is a flexible, elongated member made of metal, such as a wire.

[0090] The front caster locking member 35 is provided with a front wheel elongated hole 37D at the connection point with the inter-wheel connecting member 58D. Furthermore, the rear caster locking member 45 is provided with a rear wheel elongated hole 47D at the connection point with the rear wheel connecting member 55.

[0091] The front-wheel-side displacement member 52D of this embodiment is provided rotatably with respect to the front leg 11. As shown in FIG. 13, the front-wheel-side displacement member 52D has a case body 52aD attached to the front leg 11 and a rotating body 52bD that rotates about an axis with respect to the case body 52aD. In FIG. 13, the rotating body 52bD is indicated by light ink. The front-wheel connecting member 51 is fixed to the rotating body 52bD. Furthermore, the rotating body 52bD is rotated clockwise by a front-wheel-side first biasing member 57D, and is biased in a direction that pulls the front-wheel connecting member 51 (clockwise). The front-wheel-side first biasing member 57D is, for example, a spring, and FIG. 13 illustrates a torsion spring. The front-wheel-side first biasing member 57D is provided between the case body 52aD and the rotating body 52bD, with one end fixed to the rotating body 52bD and the other end fixed to the case body 52aD.

[0092] 12, one end of the drive member 24D in this embodiment is connected to the operation connecting member 25, which in turn is connected to the operation member 23, and the other end is connected to the above-mentioned rear caster locking member 45 via the rear wheel connecting member 55. The drive member 24D is provided on the push rod 20. As a result, the rear wheel connecting member 55, which connects the drive member 24D to the rear caster locking member 45, is passed through the rear leg 13, the inversion bracket 27, and the push rod 20 in this order. The drive member 24D is biased to a downward position by the second biasing member 26D.

[0093] (About operation) With reference to the figures, the operation of restricting or allowing rotation of the caster mechanisms 30, 40 of the stroller 1D according to this embodiment will be described. Fig. 12 shows the push bar 20 in the rear position, Fig. 12(A) shows the state when the operating mechanism is not operated, and Fig. 12(B) shows the state when the operating mechanism is operated. Fig. 14 shows the push bar 20 in the forward position, Fig. 14(A) shows the state when the operating mechanism is not operated, and Fig. 14(B) shows the state when the operating mechanism is operated.

[0094] First, with reference to Figures 12(A) and 12(B), the operation when the push bar 20 is in the rear position will be described. As shown in Figure 12(A), when the push bar 20 is in the rear position, the front caster mechanism 30 is rotatable about its rotation axis, but the rear caster mechanism 40 is prohibited from rotating about its rotation axis. As shown in Figure 13, the front caster mechanism 30 has the front wheel-side displacement member 52D urged clockwise by the front wheel-side first urging member 53D, so the front wheel connecting member 51 is wound up and the front caster locking member 35 is in the unlocked position (upper position).

[0095] In the rear caster mechanism 40, the driving member 24D is urged downward by the urging force of the second urging member 26D, and the rear caster locking member 45 is positioned in the locked position (lower position). At this time, the other end of the rear wheel connecting member 55 is positioned above the rear wheel elongated hole 47D of the rear caster locking member 45.

[0096] When the push bar 20 is in the rear position, the operating member 23 is operated to allow both the front caster mechanism 30 and the rear caster mechanism 40 to rotate about the rotation axis and achieve the drift state. As shown in FIG. 12(B), the operating member 23 is operated to pull up the operating coupling member 25, moving the drive member 24D upward against the biasing force of the second biasing member 26D, and thereby moving the rear caster locking member 45 to the unlocked position (upper position). Operating the operating mechanism 22 in this way allows both the front caster mechanism 30 and the rear caster mechanism 40 to rotate about the rotation axis, achieving the drift state. Note that when the push bar 20 is in the rear position, operating the operating member 23 does not act on the front caster locking member 35 because the front caster lock 35 has a front elongated hole 37D.

[0097] Next, the operation when the push bar 20 is in the facing position will be described with reference to Figures 14 and 15. As shown in Figure 14(A), when the push bar 20 is in the facing position, the rear caster mechanism 40 can rotate around the rotation axis, but the front caster mechanism 30 is prohibited from rotating around the rotation axis.

[0098] Specifically, as shown in Fig. 14(A), when the front-wheel-side displacement member 52D comes into contact with the drive member 24D provided on the push rod 20 displaced to the facing position, the front-wheel-side displacement member 52D rotates counterclockwise, as shown in Figs. 15(A) and 15(B), in a direction to advance the front-wheel connecting member 51. At this time, the front-wheel-side displacement member 52D is biased clockwise by the front-wheel-side first biasing member 53D, but the abutment of the drive member 24D interrupts this biasing force. As shown in Fig. 14(A), the front-wheel-side displacement member 52D advances the front-wheel connecting member 51, and the biasing force of the front-wheel third biasing member 36 positions the front-wheel caster locking member 35 in the locked position (downward position).

[0099] Since the front caster locking member 35 and the rear caster locking member 45 are connected by the inter-wheel connecting member 58D, the rear caster locking member 45 is pulled by the inter-wheel connecting member 58D and positioned in the unlocked position (upper position).

[0100] When the push rod 20 is in the facing position, in order to make not only the rear caster mechanism 40 but also the front caster mechanism 30 rotatable about the rotation axis to enter the drift state, the operating member 23 is operated. As shown in Figure 14(B), when the operating member 23 is operated to pull up the operating connecting member 25 and move the drive member 24D upward, the drive member 24D no longer abuts against the front wheel side displacement member 52D, and the biasing force of the front wheel side first biasing member 53D becomes effective.

[0101] As shown in the order of Figures 15(B) and 15(A), the rotating body 52bD of the front-wheel displacement member 52D rotates clockwise due to the biasing force of the front-wheel first biasing member 53D, pulling up the front-wheel connecting member 51. Accordingly, as shown in Figure 14(B), the front caster locking member 45 moves to the unlocked position (upper position). By operating the operating mechanism 22 in this way, not only the rear caster mechanism 40 but also the front caster mechanism 30 becomes rotatable about the rotation axis, allowing the vehicle to drift. When the push rod 20 is in the facing position, operating the operating member 23 does not act on the rear caster locking member 45 because the rear caster lock 45 has a rear elongated hole 47D.

[0102] <Fourth Embodiment> The configuration and operation of a stroller 1E according to embodiment 4 will be described with reference to Figures 16 and 17. The stroller 1E of this embodiment has the same basic configuration as that of embodiment 1, but a major difference is that the drive member 24E and rear-wheel-side displacement member 56E are not in contact with each other, but are connected by an intermediate connecting member 60E. Only the differences from the configuration shown in embodiment 1 will be described in detail.

[0103] (For each configuration) Focusing on the rear wheel 14 side, in the stroller 1E of the fourth embodiment, the drive member 24E and the rear-wheel-side displacement member 56E are connected by an intermediate connecting member 60E. The rear-wheel-side displacement member 56E of this embodiment is provided on the push rod 20 rather than on the body frame 10, and is vertically aligned with the drive member 24E. The rear-wheel-side displacement member 56E is not directly biased in one direction by a biasing member, but has a displacement-member elongated hole 59E at its upper end. The provision of the displacement-member elongated hole 59 connects the intermediate connecting member 60E to the rear-wheel-side displacement member 56E so that it can move up and down within the displacement-member elongated hole 59E. Like the rear-wheel connecting member 55 and the operation connecting member 25, the intermediate connecting member 60E is a flexible, elongated member made of metal, such as a wire.

[0104] A cam 63E that protrudes outward in the width direction of the stroller 1E (toward the push bar 20) is provided on the rear leg 13. The cam 63E is, for example, circular in side view, and is a member for vertically displacing the position of the rear wheel side displacement member 56E. The movement of the rear wheel side displacement member 56E by the cam 63E will be described later.

[0105] (About operation) With reference to the figures, the operation of restricting or allowing rotation of the caster mechanisms 30, 40 of the stroller 1E according to this embodiment will be described. Figures 16(A) and (B) show the push bar 20 in the rear position, with Fig. 16(A) particularly showing a state where the operating mechanism is not operated and Fig. 16(B) showing a state where the operating mechanism is operated. Figures 17(A) and (B) show the push bar 20 in the facing position, with Fig. 17(A) particularly showing a state where the operating mechanism is not operated and Fig. 17(B) showing a state where the operating mechanism is operated.

[0106] First, with reference to Figures 16(A) and (B), the operation when the push bar 20 is in the rear position will be described. As shown in Figure 16(A), when the push bar 20 is in the rear position, the front caster mechanism 30 is rotatable about its axis of rotation, but the rear caster mechanism 40 is prohibited from rotating about its axis of rotation. Specifically, in the front caster mechanism 30, the front wheel displacement member 52E is urged upward by the front wheel first urging member 53, so the front wheel connecting member 51 is pulled up and the front caster locking member 35 is positioned in the unlocked position (upper position).

[0107] 16(B), the operating member 23 is operated to pull up the operating connecting member 25, and the driving member 24E is moved upward against the biasing force of the second biasing member 26. Because the intermediate connecting member 60E is positioned above the displacement member elongated hole 59 of the rear-wheel-side displacement member 56E, the rear-wheel-side displacement member 56E also moves upward. As a result, the rear leg connecting member 55 moves upward, and the rear-wheel caster locking member 45 can be moved to the unlocked position (upper position).

[0108] Next, the operation when the push bar 20 is in the facing position will be described with reference to Figures 17(A) and (B). As shown in Figure 17(A), when the push bar 20 is in the facing position, the rear caster mechanism 40 can rotate around the rotation axis, but the front caster mechanism 30 is prohibited from rotating around the rotation axis.

[0109] Specifically, when the push bar 20 is slid from the rear position to the facing position, the rear-wheel-side displacement member 56E comes into contact with the cam 63E attached to the rear leg 13 and moves upward. As a result, the rear-leg caster locking member 45 moves upward against the biasing force of the third biasing member 46, and the rear-wheel caster locking member 45 is pulled by the rear-wheel connecting member 55 and moves to the unlocked position (upper position). Furthermore, the lower end of the displacement member elongated hole 59E of the rear-wheel-side displacement member 56E coincides with the lower end of the intermediate connecting member 60E. The front-wheel-side displacement member 52E comes into contact with the drive member 24E provided on the push bar 20 displaced to the facing position, and as shown in FIG. 17(A), the front-wheel-side displacement member 52E moves downward, advancing the front-wheel connecting member 51. The front wheel connecting member 51 is sent out by the front wheel side displacement member 52E, and the biasing force of the front wheel third biasing member 36 positions the front caster locking member 35 in the lock position (lower position).

[0110] As shown in Figure 17(B), the operating member 23 is operated to pull up the operation connecting member 25, thereby moving the drive member 24E upward against the biasing force of the second biasing member 26. The front-wheel-side displacement member 52E, which had been in contact with the drive member 24E, is moved upward by the biasing force of the front-leg-side first biasing member 53E, thereby moving the front-wheel caster locking member 35 to the unlocked position (upper position). Before this operation is performed, the lower end of the intermediate connecting member 60E is positioned at the lower end of the displacement member elongated hole 59E of the rear-wheel-side displacement member 56E, as shown in Figure 17(A). Therefore, even if the operating member 23 is operated to pull up the operation connecting member 25 and pull up the intermediate connecting member 60E upward, the position of the rear-wheel-side displacement member 56E will not move, as shown in Figure 17(B).

[0111] <Fifth Embodiment> The configuration and operation of a stroller 1F according to embodiment 5 will be described with reference to Figures 18 to 20. The stroller 1F of this embodiment has the same basic configuration as that of embodiment 3, but a major difference is that a front-wheel displacement member and a wheel connecting member are not provided, and connecting members 65F, 66F are connected to an inter-wheel displacement member 64F. Only the differences from the configuration shown in embodiment 3 will be described in detail.

[0112] (For each configuration) The inter-wheel displacement member 64F is provided so that its own length can be displaced by the inter-wheel displacement member 64F. The inter-wheel displacement member 64F is provided rotatably with respect to the rear leg 13. As shown in FIG. 20(A), the inter-wheel displacement member 64F has a case body 64aF attached to the rear leg 13 and a rotating body 64bF that rotates about an axis relative to the case body 64aF. In FIG. 20, the rotating body 64bF is indicated by light ink. A front wheel connecting member 58F and a second rear wheel connecting member 66F are fixed to the rotating body 64bF in an offset manner. Furthermore, the rotating body 64bF is rotated clockwise by the front wheel side first biasing member 57F, pulling the front wheel connecting member 51 and sending out the second rear wheel connecting member 66F. The front wheel side first biasing member 53F is, for example, a spring, and FIG. 20 illustrates a torsion spring. The front-wheel-side first biasing member 53F is provided between the case body 64aF and the rotating body 64bF, with one end fixed to the rotating body 64bF and the other end fixed to the case body 64aF.

[0113] (About operation) With reference to the same figures, the operation of restricting or allowing rotation of the caster mechanisms 30, 40 of the stroller 1F according to this embodiment will be described. Figures 18(A) and (B) show the push bar 20 in the rear position, and in particular, Figure 18(A) shows the state in which the operating mechanism is not operated, and Figure 18(B) shows the state in which the operating mechanism is operated. Figure 19 shows the state in which the push bar 20 is in the facing position.

[0114] First, with reference to Figures 18(A) and (B), the operation when the push bar 20 is in the rear position will be described. As shown in Figure 18(A), when the push bar 20 is in the rear position, the front caster mechanism 30 is rotatable about its rotation axis, but the rear caster mechanism 40 is prohibited from rotating about its rotation axis. Specifically, in the front caster mechanism 30, the front wheel-side displacement member 52 is urged clockwise by the front wheel-side first urging member 53F, and is urged in the direction of winding up the front wheel connecting member 51, so that the front caster locking member 35 is in the unlocked position (upper position).

[0115] As shown in Figure 18 (B), when the operating member 23 is operated to pull up the operating connecting member 25, the first rear leg connecting member 55F moves upward, and the rear wheel caster locking member 45 can be moved to the unlocked position (upper position).

[0116] Next, the operation when the push bar 20 is in the facing position will be described with reference to Figure 19. As shown in Figure 19, when the push bar 20 is in the facing position, the rear caster mechanism 40 is rotatable about its axis of rotation, while the front caster mechanism 30 is prohibited from rotating about its axis of rotation.

[0117] Specifically, when the push bar 20 is slid from the rear position to the facing position, the inter-wheel displacement member 64F is biased clockwise by the front-wheel-side first biasing member 53F, but the inter-wheel displacement member 64F abuts against the push bar 20 displaced to the facing position, and as shown in FIGS. 19 and 20(B), the inter-wheel displacement member 64F rotates counterclockwise, advancing the front-wheel connecting member 58F. The rotating body 64bF rotates against the biasing force of the front-wheel third biasing member 36, advancing the front-wheel connecting member 58F and retracting the second rear-wheel connecting member 66F. In this way, by swinging the push bar 20, the front-wheel caster locking member 35 moves to the locked position (lower position), and the rear-wheel caster locking member 45 moves to the unlocked position (upper position).

[0118] <Regarding modified examples spanning multiple embodiments> In all embodiments except for the variant of embodiment 2, the front wheels 12 and rear wheels 14 have been described as being casters, but it is sufficient that at least one of the four wheels is a caster, and the other three wheels may be simple wheels that do not rotate around a vertical axis, or at least one of the pair of front wheels 12 or the pair of rear wheels 14 may be a caster.

[0119] In all the embodiments except for the modified example of the second embodiment, the push rod 20 is provided so as to be slidable between the rear position and the facing position relative to the swing shaft 21, but the push rod 20 does not necessarily have to be slidable. For example, the push rod 20 may be detachable from the body frame 10 and may be detached and fixed to the body frame 10 when switching between the rear position and the facing position. In other words, the push rod 20 may be one that can be switched between the rear position and the facing position, and the means for doing so is not limited.

[0120] In addition, in the above embodiment, a first biasing member that biases the wheel locking member to the locked position and a second biasing member that biases the operating member to the first position (upper position) are provided, but these do not necessarily have to be provided in the brake mechanism and can be selected depending on the required accuracy of the brake mechanism.

[0121] In the above embodiment, it has been described that the front caster locking member 35 is provided on the front caster holding member 41, and the rear caster locking member 45 is provided on the rear caster holding member 46, but they may also be provided on the front caster fixing member 42 or the rear caster fixing member 47, as long as they are provided on the front caster mechanism 30 or the rear caster mechanism 40.

[0122] In the above embodiment, third biasing members 36, 46 were provided to bias the caster locking members 35, 45 to the locked position, but these are provided to stabilize the operation of the caster locking members 35, 45 and are not an essential configuration.

[0123] Although the drive members 24, 24D, and 24E in the first, second, third, and fourth embodiments are operable by the operation member 23 of the operation mechanism 22 and constitute part of the operation mechanism 22, they may be provided as standalone units. For example, the drive members 24, 24D, and 24E may be manually operable, or may be provided with a fixing portion for fixing them to the push rod 20 so that they can be held in position.

[0124] Although a plurality of embodiments have been described in this specification, the configurations of the embodiments may be extracted and combined with each other.

[0125] Although the embodiments of the present invention have been described above with reference to the drawings, the present invention is not limited to the illustrated embodiments. Various modifications and variations can be made to the illustrated embodiments within the same scope as the present invention or within an equivalent scope. [Explanation of symbols]

[0126] 1, 1A, 1B, 1C, 1D, 1E, 1F stroller, 10 body frame, 11 front legs, 12 front wheels, 13 rear legs, 14 rear wheels, 20 push rod, 22 operation mechanism, 23 operation member, 24, 24A, 24D, 24E drive member, 25 operation connecting member, 26, 26D second biasing member, 30 front wheel caster mechanism, 31 front wheel caster holding member, 32 front wheel caster rotating member, 35 front wheel caster locking member, 36 third biasing member, 40 rear wheel caster mechanism, 41 rear wheel caster holding member, 42 rear wheel caster rotating member, 45 rear wheel caster locking member, 46 third biasing member, 51, 51A, 58F front wheel connecting member, 52, 52A, 52D Front wheel side displacement member, 53, 53D, 53E, 53F, 57, 57D first biasing member, 56, 56A, 56D, 56E rear wheel side displacement member, 58D inter-wheel connecting member, 60E intermediate connecting member, 63E cam, 64F inter-wheel displacement member.

Claims

1. a body frame including front legs, rear legs, and a push bar switchable between a rearward position and a forward-facing position; a caster mechanism including a caster holding member provided at a lower end of the front leg or the rear leg, and a caster rotation member that is held by the caster holding member so as to be rotatable about a rotation axis extending in the vertical direction and supports the front wheel or the rear wheel, and that enables the direction of the front wheel or the rear wheel to be turned; a caster locking member provided in the caster mechanism, the caster locking member restricting rotation of the caster rotation member in a locked position and allowing rotation of the caster rotation member in an unlocked position; a displacement member that is provided on the vehicle body frame, connected to the caster locking member via a connecting member, and displaced between a first position corresponding to the locked position of the caster locking member and a second position corresponding to the unlocked position of the caster locking member in accordance with switching of the push rod; a push rod provided with an operating mechanism for operating the displacement member from the first position to the second position;

2. The wheeled childcare apparatus according to claim 1 , further comprising a first biasing member that biases the displacement member to the second position.

3. the operation mechanism includes an operation member and a drive member coupled to the operation member and switched between a first state and a second state by an operation force of the operation member; the drive member in the first state brings the displacement member to the first position; The wheeled childcare apparatus according to claim 1 or 2, wherein the drive member in the second state brings the displacement member to the second position.

4. the operation mechanism includes an operation member and a drive member coupled to the operation member and switched between a first state and a second state by an operating force of the operation member; The drive member in the first state interrupts the biasing force of the first biasing member acting on the displacement member, The childcare apparatus with wheels according to claim 2 , wherein the drive member in the second state enables the biasing force of the first biasing member acting on the displacement member.

5. the operating mechanism further includes a second biasing member that biases the drive member toward the first state; The childcare apparatus with wheels according to claim 4 , wherein the biasing force of the second biasing member is greater than the biasing force of the first biasing member.

6. a third biasing member that biases the caster locking member to the locked position; The childcare apparatus with wheels according to claim 5 , wherein the biasing force of the third biasing member is smaller than the biasing force of the first biasing member.

7. The caster mechanism includes: a front caster mechanism that includes a front caster holding member provided at the lower end of the front leg, and a front caster rotating member that is held by the front caster holding member so as to be rotatable about a rotation axis extending in the vertical direction and supports the front wheels, and that enables the front wheels to rotate; a rear caster mechanism that includes a rear caster holding member provided at the lower end of the rear leg, and a rear caster rotating member that is held by the rear caster holding member so as to be rotatable about a rotation axis extending in the vertical direction and supports the rear wheel, and that enables the rear wheel to rotate; The caster locking member is a front caster locking member that is provided in the front caster mechanism and restricts rotation of the front caster rotating member at the locked position and allows rotation of the front caster rotating member at the unlocked position; 3. The wheeled childcare equipment according to claim 1, further comprising a rear caster locking member provided on the rear caster mechanism, which restricts the rotation of the rear caster rotation member in the locked position and allows the rotation of the rear caster rotation member in the unlocked position.

8. The displacement member is a front-wheel-side displacement member provided on the front leg, connected to the front-wheel caster locking member, and pressed by the push rod as the push rod is switched, to displace between a first position corresponding to the locked position of the front-wheel caster locking member and a second position corresponding to the unlocked position of the front-wheel caster locking member; 8. The wheeled childcare apparatus according to claim 7, further comprising a rear-wheel-side displacement member provided on the rear leg, connected to the rear-wheel caster locking member, and pressed by the push rod as the push rod is switched, to displace between a first position corresponding to the locked position of the rear-wheel caster locking member and a second position corresponding to the unlocked position of the rear-wheel caster locking member.

9. The childcare implement with wheels according to claim 1 or 2, wherein the displacement member is provided so as to be movable up and down along the body frame.

10. The childcare implement with wheels according to claim 1 or 2, wherein the displacement member is provided rotatably with respect to the body frame.

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