JP5138231B2 - Caster and stroller having the caster - Google Patents

Description

  The present invention relates to a caster having a lock function for preventing turning of a wheel, and a stroller using the caster.

A front wheel of a stroller, and in some cases, a front wheel and a rear wheel are attached to a leg frame using a caster having a lock function for preventing the wheel from turning (see, for example, Patent Document 1).
JP 2002-284015 A

  When torque is input from the road surface to the wheels while preventing the wheels of the casters from turning, a load is applied to the components involved in turning prevention. When the load is excessively large, there is a possibility that inconveniences such as deformation or breakage of caster components occur.

  Therefore, an object of the present invention is to provide a caster in which parts are hardly deformed or damaged even when excessive torque is input to the wheel, and a stroller using the caster.

The caster (101) of the present invention includes a caster body (103) to which a wheel (10) is attached, and a caster holder (102) that rotatably supports the caster body around a turning center line orthogonal to the axis of the wheel. And a lock position (position shown in FIG. 49) that meshes with the caster body around the turning center line so as not to rotate relative to the caster body, and retracts toward the caster holder along the turning center line from the lock position. It can be moved between a release position (the position shown in FIG. 48) where the meshing with the main body is released, and is attached to the caster holder around the turning center line so as not to be rotatable relative to the caster holder. A locking member (104), and an engagement portion between the locking member and the caster body is input to the caster body. A torque about the rotational center line, the tapered portion by converting from the locking position in the direction of the force toward the release position to act on the locking member (104e, 108a) is provided, the locking member and the caster holder and between, the Rukoto recess (106b) and the protrusion (104d) is provided to engage with each other when the locking member is in the release position, to solve the problems described above.

  According to the caster of the present invention, when the lock member is operated to the lock position, the lock member is engaged with the caster body, and the turning of the caster body with respect to the caster holder is prevented. When the lock member is moved from the lock position to the release position, the engagement between the lock member and the caster main body is released, and the caster main body can turn with respect to the caster holder together with the wheels. When torque is input from the wheel to the caster body when the lock member is in the locked position, the torque pushes the lock member to the release position between the tapered portions provided at the meshing portion between the lock member and the caster body. It is converted into force and acts on the locking member. When the converted force exceeds the force necessary for the operation of the lock member, the lock member is driven to the release position. Therefore, when excessive torque is input to the caster body, the lock member can be retracted to the release position, thereby avoiding inconveniences such as deformation or breakage of parts.

  In the caster of the present invention, guide means (106a, 104d) for guiding the lock member in the direction of the turning center line may be provided between the caster holder and the lock member. According to this aspect, the lock member can be smoothly operated in the direction of the turning center line using the guide means.

  The guide means is provided on one of the caster holder and the lock member and provided on one of the other of the caster holder and the lock member, and a guide rail (104d) extending in the direction of the turning center line. A rail groove (106a) that meshes with the guide rail may be provided. In this case, the lock member can be reliably guided in the direction of the turning center line by mounting the lock member on the caster holder so that the guide groove and the guide rail are engaged with each other.

  A concave portion (106c) and a convex portion (104d) that mesh with each other when the lock member is in the lock position may be provided between the caster holder and the lock member. By engaging the concave portion and the convex portion at the lock position, an action of holding the lock member at the lock position is generated, and thereby resistance can be given to the backward movement from the lock position to the release position. . The region in which the lock member is retracted by the force converted by the tapered portion can be appropriately adjusted according to the degree of engagement between the concave portion and the convex portion.

  The lock member may be fitted to the outer periphery of the caster holder using elasticity. According to this, the lock member can be easily attached to the caster holder.

  The stroller (1) of the present invention includes the caster (101) described above, and the caster holder (102) of the caster is connected to the leg (4), thereby solving the above-described problem. According to the stroller of the present invention, when a large torque is inadvertently input to the wheel in a state where the lock member is switched to the lock position to prevent the wheel from turning, the wheel is allowed to turn and the caster is Damage can be avoided.

  The stroller of the present invention has a three-wheel structure including a single front wheel (10) disposed in the center in the vehicle width direction and a pair of rear wheels (11) disposed on both sides in the vehicle width direction. But you can. In this case, the front wheel may be attached to the front leg (4) via the caster (101). In the case of a three-wheeled baby stroller, a large torque is easily applied particularly to the front wheel. Therefore, the caster of the present invention can be effectively utilized by applying the caster of the present invention to the front wheel.

  In addition, in the above description, in order to make an understanding of this invention easy, the reference sign of the accompanying drawing was attached in parenthesis, but this invention is not limited to the form of illustration by it.

  As described above, according to the caster of the present invention, when torque is input from the wheel to the caster body when the lock member is in the locked position, the torque is provided at the meshing portion between the lock member and the caster body. When the force is converted into a force that pushes the lock member to the release position between the tapered portions and acts on the lock member, and the converted force exceeds the force necessary for the operation of the lock member, the lock member moves to the release position. And driven. Therefore, when excessive torque is input to the caster body, the lock member can be retracted to the release position, thereby avoiding inconveniences such as deformation or breakage of parts.

  FIG. 1 is a perspective view of a stroller according to an embodiment of the present invention. First, the overall configuration of the stroller 1 will be described. The stroller 1 includes a vehicle body 2 and a seat 3 supported by the vehicle body 2. The vehicle body 2 includes a front leg 4, a pair of rear legs (only one side is shown in FIG. 1) 5, a pair of armrests 6, a pair of seat frames 7, and a hand frame 8. The front leg 4 has a pair of front leg frames 9. The front leg frame 9 is formed using a hollow pipe material, and the lower ends thereof are gathered at the center of the vehicle body 2 in the left-right direction (sometimes referred to as the vehicle width direction), and the front wheel 10 is attached to the lower end thereof. . A rear wheel 11 is attached to each lower end of the rear leg 5. The front wheel 10 has a configuration in which a pair of tires 10a are coaxially connected by an axle 10b. The distance in the axle direction between the tires 10 a is extremely small as compared with that between the rear wheels 11. Thereby, the front wheel 10 is comprised as a substantially single wheel. That is, the stroller 1 is configured as a three-wheeled stroller including a single front wheel 10 and a pair of rear wheels 11. The front wheel 10 can turn around the vertical axis, and the details of the structure will be described later.

  The seat 3 includes a seat cushion portion 12 and a seat back portion 13. Each of the seat cushion portion 12 and the seat back portion 13 has a configuration in which a resin-made substrate (a seat plate or a back plate) as a core material is covered with a shock-reducing pad, a skin material, or the like. The respective substrates of the seat cushion portion 12 and the seat back portion 13 are configured as separate components, and are connected to each other by a hinge portion 14 so as to be rotatable. The axis of the hinge portion 14 is directed in the left-right direction of the vehicle body 2. The seat cushion portion 12 is supported from below by a seat stay (not shown) spanned between the left and right seat frames 7. On the other hand, the seat back portion 13 is supported on both sides in the left-right direction by left and right back frames 15 that constitute a part of the hand push frame 8. The back frame 15 is formed of a hollow pipe material over its entire length. In addition to the back frame 15 described above, the hand push frame 8 includes an operation unit 16 disposed between upper end portions of the back frame 15 and a handle 17 attached to the operation unit 16. A resin leg rest 18 is attached between the front leg frames 9 of the front leg 4. In addition, although accessories such as an awning are provided in the stroller 1, illustration thereof is omitted. Next, details of each part of the stroller 1 will be described in order.

(Body link mechanism)
First, a link mechanism for deforming the vehicle body 2 will be described. FIG. 2 is a side view showing the configuration of one side of the vehicle body 2 in the left-right direction (width direction). The opposite side has the same configuration. The left-right direction in FIG. 2 corresponds to the front-rear direction of the vehicle body 2, the direction orthogonal to the paper surface corresponds to the left-right direction (sometimes referred to as the vehicle width direction), and the left side in FIG. . The vertical direction of the vehicle body 2 corresponds to the vertical direction of FIG. As is apparent from FIG. 2, the front end of the armrest 6 is connected to the upper end of the front leg frame 9 so as to be rotatable about the fulcrum Pa, and the rear end of the armrest 6 is rotatable via the back frame 15 and the fulcrum Pb. Connected to A seat frame bracket 22 is fixed in the middle of the front leg frame 9, and the seat frame bracket 22 is connected to the front end of the seat frame 7 so as to be rotatable around a fulcrum Pc. The rear end of the seat frame 7 is connected to a link connecting component 23 fixed to the lower end of the back frame 15 so as to be rotatable about a fulcrum Pd. Thereby, the substantially parallelogram-shaped first link mechanisms L1 are formed on both sides of the vehicle body 2, respectively. By operating the first link mechanism L1, the vehicle body 2 can be deformed between the use state shown in FIG. 2 and the folded state shown in FIG. In FIG. 3, the hood Hd attached to the back frame 15 is also drawn in a folded state. FIG. 4 shows how the vehicle body 2 is changed from the use state to the folded state in several stages. FIG. 5 is a simplified mechanism diagram of the first link mechanism L1. In FIG. 5, the first link mechanism L1 in the use state is indicated by a solid line, and the first link mechanism L1 in the folded state is indicated by an imaginary line. For convenience, the position of the front leg frame 9 is unchanged between the two states.

  As is clear from FIGS. 4 and 5, the first link mechanism L1 folds the seat 3 around the hinge portion 14 (see FIG. 1) as the vehicle body 2 changes from the use state to the folded state. In addition, the back frame 15 of the hand push frame 8 acts so as to move downward substantially in parallel. The rear legs 5 and the rear wheels 11 are displaced toward the front legs 4 in conjunction with the folding operation of the first link mechanism L1. The operation of the rear leg 5 is realized by a second link mechanism L2 described below.

  6A is a side view showing the relationship between the front legs 4 and the rear legs 5 when the vehicle body 2 is in use, and FIG. 7A shows the relationship between the front legs 4 and the rear legs 5 when the vehicle body 2 is in a folded state. It is a side view. As shown in these drawings, the rear leg 5 includes an upper arm 25 and a lower arm 26 as a pair of rear leg arms. The upper arm 25 and the lower frame 26 are disposed substantially parallel to each other, and function as link parts that constitute the second link mechanism L2. The upper and lower arms 25, 26 are connected to the rear leg bracket 27 at their front ends so as to be rotatable around fulcrums Qa, Qb, and are connected at the rear end to the rear wheel carrier 28 so as to be rotatable around fulcrum pins Qc, Qd. The The upper and lower arms 25, 26, the rear leg bracket 27, and the rear wheel carrier 28 form a second link mechanism L2 having a substantially parallelogram shape. In order to link the first link mechanism L1 and the second link mechanism L2, the seat frame 7 of the first link mechanism L1 and the upper arm 25 of the second link mechanism L2 are connected to each other via a connecting rod 30. ing. By operating the first link mechanism L1, the operation of the seat frame 7 is transmitted to the upper arm 25 via the connecting rod 30, and the second link mechanism L2 operates.

  6B is a view showing a state in which the left and right rear legs 5 are looked down along the longitudinal direction of the front leg frame 9 when the vehicle body 2 is in use, and FIG. 7B is a view of the left and right rear legs when the vehicle body 2 is in a folded state. FIG. 5 is a view showing a state in which 5 is looked down along the longitudinal direction of the front leg frame 9. As is clear from these drawings, the rear leg bracket 27 is attached to a rear leg stay 31 that is bridged between the front leg frames 9. The rear leg stay 31 is fixed to the front leg frame 9 by using a fixture 32 (see FIGS. 6A and 7A) such as a rivet. As a result, the rear leg bracket 27 cannot be displaced relative to the front leg 4. The rear leg bracket 27 is disposed symmetrically with respect to the longitudinal center line CL of the vehicle body 2 (a line dividing the vehicle body 2 into two equal parts in the vehicle width direction). The rotation center line Aq for the rear leg bracket 27 of the upper and lower arms 25, 26 (only the upper arm 25 is shown in FIGS. 6B and 7B) is such that the outer side of the vehicle width direction inner side is biased forward and upward of the vehicle body 2. It is inclined obliquely with respect to the width direction. The rotation center line Aq is a center line when the upper and lower arms 25 and 26 are rotated around the fulcrums Qa and Qb.

  As the rotation center line Aq is inclined in this way, the rear leg 5 extends obliquely from the rear leg bracket 27 toward the outside in the vehicle width direction. Thereby, the distance in the vehicle width direction of the rear wheel 11 (the direction of the rear wheel axis Aw) is larger than the distance in the vehicle width direction between the rear leg brackets 27. Moreover, the distance between the rear wheels 11 decreases as the rear leg 5 approaches the front leg frame 9 around the rotation center line Aq. Therefore, the distance between the rear wheels 11 becomes the maximum value Da (FIG. 6B) when the vehicle body 2 is in use, and becomes the minimum value Db (FIG. 7B) when the vehicle body 2 is folded. Thereby, in the folded state, the rear wheel 11 can be pulled inward in the vehicle width direction, and the vehicle body 2 can be compactly gathered in the vehicle width direction. Even if the rear leg 5 is inclined with respect to the longitudinal center line CL, the axle 11a of the rear wheel 11 is supported in parallel with the vehicle width direction by the rear wheel carrier 28 in use. Since the second link mechanism L2 is configured as a substantially parallelogram-shaped link mechanism, the axle 11a of the rear wheel 11 is supported in parallel with the vehicle width direction even when the vehicle body 2 is folded. Therefore, the stroller 1 can be carried while being rolled using the front wheel 10 and the rear wheel 11 not only in the use state but also in the folded state. As long as the operation of the rear wheel 11 is not hindered, the axle 11a of the rear wheel 11 may be somewhat inclined with respect to the vehicle width direction. In this embodiment, since the back frame 15 is moved substantially in parallel to switch between the use state and the folded state, the handle 17 is maintained at a relatively high position even in the folded state. Therefore, the vehicle body 2 can be deformed by operating the hand push frame 8 while the user is standing. That is, the user is not forced to have an unnatural posture that crouches. Even in the folded state, the stroller 1 can be rolled and carried while holding the handle 17.

  In addition, in each of the fulcrums Pa to Pd in the first link mechanism L1 and the fulcrums Qa to Qd in the second link mechanism L2, the link parts are rotatably connected by pins and other various connecting means.

(Connection rod and its connection structure)
Next, the connecting rod 30 and the structure for connecting it will be described. FIG. 8 is an enlarged view showing the vicinity of the connecting rod 30. As described above, the connecting rod 30 connects the seat frame 7 and the upper arm 25 of the rear leg 5, while the rotation center line of the seat frame 7 is parallel to the vehicle width direction, whereas the upper arm 25. The rotation center line of the vehicle body 2 is inclined as described above, and therefore, not only in the longitudinal direction and the vertical direction of the vehicle body 2 but also in the vehicle width direction between the coupling points of the coupling rod 30 and the seat frame 7 and the upper arm 25. Relative displacement also occurs. In order to allow such a relative displacement in the three axial directions, a universal joint is interposed between the connecting rod 30, the seat frame 7, and the upper arm 25. That is, the connecting rod 30 and the seat frame 7 are connected via the ball joint 35, and the connecting rod 30 and the upper arm 25 are connected via the universal joint 36.

  9 is an enlarged view of the ball joint 35, FIG. 10 is a perspective view of the ball joint 35 as viewed from below, and FIG. 11 is a cross-sectional view taken along the line XI-XI in FIG. As shown in these drawings, the ball joint 35 includes a base 37 that is fixed to the seat frame 7, a ball housing 38 that covers the base 37, and a ball 39 that is built in the ball housing 38. As shown in FIGS. 12 to 14, the base 37 is provided with a top flange 37 a, a mounting hole 37 b through which the seat frame 7 is passed, and a ball joint cap 37 c. A guide surface 37d that is curved in a spherical shape is formed at the lower end of the ball joint cap 37c. As shown in FIGS. 11 and 15, the ball housing 38 is provided with a cylindrical portion 38a that fits on the outer periphery of the ball joint cap 37c, and the inner periphery on the lower end side of the cylindrical portion 38a is curved in a spherical shape. A guide surface 38b is formed. As shown in FIGS. 11 and 14, the ball 39 is coaxially fixed to the shaft end portion of the connecting rod 30 using a countersunk screw 40.

  In order to connect the connecting rod 30 to the seat frame 7 using the ball joint 35, first, the ball 39 is fixed to the connecting rod 30. At this stage, the connecting rod 30 is passed through the ball housing 38. Then, as shown in FIGS. 11 and 12, the ball 39 abuts against the guide surface 37d of the ball joint cap 37c. Next, the ball housing 38 is fitted to the outer periphery of the ball joint cap 37c. Then, the rivet 41 is driven from one side of the ball joint cap 37 c so as to penetrate the base 37 and the seat frame 7, and the leading end portion of the rivet 41 is passed to the opposite side of the ball housing 38 to be crimped. Thus, the connecting rod 30 and the seat frame 7 are connected in a state where the ball 39 is sandwiched between the guide surfaces 37d and 38b. As the ball 39 slides along the guide surfaces 37 d and 38 b, the connecting rod 30 can be freely displaced around the center point of the ball 39.

  FIG. 16 is a cross-sectional view of a universal joint 36 for connecting the connecting rod 30 and the upper arm 25. The universal joint 36 includes a U-shaped first connector 44 that is rotatably attached to the upper arm 25 via a pin 43, and a second connector 45 that is disposed inside the first connector 44. doing. The connecting rod 30 is disposed coaxially with the pin 43 inside the second connecting tool 45. A cover 46 is put on the outside of the first connector 44, and the cover 46, the second connector 45, and the connecting rod 30 are connected to each other by a pin 47. The second connector 45 and the connecting rod 30 are rotatable around the pin 47 with respect to the first connector 44, and the first connector 44 is rotatable around the pin 43 with respect to the upper arm 25. . Accordingly, the connecting rod 30 can be freely displaced about the two axes of the pins 43 and 47 with respect to the upper arm 25. As is apparent from FIG. 8, the universal joint 36 is attached to the outer surface of the upper arm 25 in the vehicle width direction.

  As described above, by interposing the ball joint 35 and the universal joint 36 between the both ends of the connecting rod 30 and the seat frame 7 and the upper arm 25, the connecting point between the connecting rod 30 and both the frames 7 and 25 can be reduced. Thus, the link operation can be smoothly transmitted from the seat frame 7 to the upper arm 25. Further, the ball joint 35 has a simple structure in which the ball 39 is simply sandwiched between the ball joint cap 37c of the base 37 and the housing 38, and the sliding portion between the parts is the ball 39 and the guide surfaces 37d, 38b. Therefore, the number of parts is reduced, which is advantageous for downsizing and weight reduction. By integrating the sliding portions, the operation of the connecting rod 30 is also facilitated. By forming the ball joint cap 37c from a soft material, it is possible to impart an impact relaxation function to the ball joint 35. Further, since the countersunk screw 40 is passed through the ball 39 and the ball 39 and the connecting rod 30 are connected, it is easy to increase the diameter of the countersunk screw 40, and the ball joint has sufficient strength to withstand the folding operation of the vehicle body 2. 35 can be easily given. In this embodiment, the combination of the connecting rod 30, the ball joint 35 and the universal joint 36 corresponds to the link connecting means. The ball joint 35 may be disposed on the upper arm 25 side, and the universal joint 36 may be disposed on the seat frame 7 side. Ball joints 35 may be disposed at both ends of the connecting rod 30.

(Second lock mechanism)
Next, the second lock mechanism of the vehicle body 2 will be described. As shown in FIGS. 2 and 3, an extension arm 50 is fixed to the lower end portion of the back frame 15 so as to extend the back frame 15 downward. The extension arm 50 is attached to the left and right back frames 15 and is displaced integrally with the back frame 15. As shown in FIGS. 17 and 18, a sheet stay 51 is bridged between the left and right extension arms 50 (only one side is shown in the figure). The seat stay 51 supports the seat cushion portion 12 (see FIG. 1) from below in cooperation with a seat stay (not shown) spanned between the seat frames 7. A second lock mechanism 52 is provided between the seat stay 51 and the upper arm 25 of the rear leg 5. The second lock mechanism 52 is provided for the purpose of reducing backlash when the vehicle body 2 is in use in cooperation with the main lock mechanism 70 shown in FIG. 24, and corresponds to an inter-link lock mechanism. . The main lock mechanism 70 will be described later.

  When the vehicle body 2 is in use, the second lock mechanism 52 abuts the blocks 53 fixed to both ends of the seat stay 51 against the fixed claws 55 fixed to the upper arm 25 using rivets 54. It restrains from 25 longitudinal direction front (right side in a figure). Furthermore, the back frame 15 and the rear leg 5 are mutually restrained by holding the block 53 from above and from the front by the lock slider 56 adjacent to the fixed claw 55. The lock slider 56 is slidable in the longitudinal direction of the frame 25 along the long hole 25a by being attached to the long hole 25a of the upper arm 25 using the pin 56a. An operation lever 57 is arranged behind the lock slider 56, and the operation lever 57 is operated to rotate between the lock position shown in FIG. 17 and the release position shown in FIG. Is possible. A spring means (not shown) for urging the lock slider 56 forward of the frame 25 is provided inside the upper arm 25, and the lock slider 56 is disposed between the lock slider 56 and the operation lever 57 in the longitudinal direction of the frame 25. Linking means (not shown) such as a wire for pulling backward and a link mechanism are arranged. When the operation lever 57 is operated to the lock position in FIG. 17, the lock slider 56 is drawn to the position in FIG. 17 by the linkage member, and the block 53 is engaged with the lock slider 56. When the operating lever 57 is operated to the release position in FIG. 18, the lock slider 56 is moved forward in the longitudinal direction of the frame 25 by the force of the spring means as indicated by the arrow F in the figure, whereby the block 53 is moved to the lock slider 56. Released from. That is, when the vehicle body 2 is in a use state, the operation lever 57 is switched to the lock position and the block 53 is restrained by the lock slider 56, and when the vehicle body 2 is folded, the operation lever 57 is switched to the release position and the block 53 is moved. Release from the lock slider 56.

  19 and 20 show another form of the second lock mechanism 52. FIG. In this embodiment, a lock arm 59 is attached to the upper arm 25 in place of the fixing claw 55 and the lock slider 56 shown in FIGS. The lock arm 59 holds the block 53 from above and from the front similarly to the lock slider 56, but its position is unchanged by the upper arm 25. That is, the lock arm 59 is fixed at a fixed position of the upper arm 25. The lock arm 59 has a lock claw 59a at its rear end. The lock claw 59a is movable between a position protruding from the upper arm 25 as shown in FIG. 19 and a position retracting into the upper arm 25 as shown in FIG. Further, a linkage means is disposed between the lock claw 59a and the operation lever 57. When the operation lever 57 is switched to the lock position, the lock claw 59a is switched to the position shown in FIG. 19 and the operation lever 57 is switched to the release position. The lock claws 59a are moved to the positions shown in FIG. In this embodiment, when the vehicle body 2 is in a use state, the operation lever 57 is switched to the lock position to prevent the block 53 from escaping from the lock arm 59 with the lock claw 59a, and when the vehicle body 2 is folded, the operation lever 57 Is switched to the release position, and the lock claw 59a is moved backward to enable the block 53 to be pulled out from the lock arm 59.

  According to the second lock mechanism 52 as described above, when the vehicle body 2 is in use, the upper arm 25 of the rear leg 5 and the back frame 15 are connected via the extension arm 50, and the rattling of the vehicle body 2 is noticeable. Can be suppressed. When the vehicle body 2 is folded, the connection between the back frame 15 and the upper arm 25 can be released simply by switching the operation lever 57 on the rear leg 5 to the release position, so that the operation is easy. In addition, when the vehicle body 2 is folded, the user can easily access the operation lever 57 because the user is located on the hand push frame 8 side, that is, behind the vehicle body 2.

(Rear wheel carrier)
Next, the rear wheel carrier 28 will be described with reference to FIGS. 21 and 22. The rear wheel carrier 28 includes a carrier body 60 and a bearing block 61. The carrier body 60 is connected to the upper and lower arms 25 and 26 of the rear leg 5 at fulcrums Qc and Qd. The axle 11a of the rear wheel 11 is rotatably attached to the bearing block 61. The carrier body 60 and the bearing block 61 are rotatably connected through a single connecting pin 62. Further, as shown in FIG. 22, a cushion member 63 is provided between the carrier body 60 and the bearing block 61. For example, rubber can be used for the cushion member 63. A spring may be used as a cushion member instead of rubber. By incorporating the cushion member 63 in the rear wheel carrier 28, the shock input to the rear wheel 11 is buffered by the cushion member 63 and the impact transmitted to the rear leg 5 is reduced. Thereby, it is difficult for an impact to be transmitted to the hand push frame 8 or the seat 3, and both the operational feeling and the riding comfort of the stroller 1 are improved.

(Main lock mechanism)
FIG. 23 is an enlarged view showing the configuration in the vicinity of the fulcrum Pd of the first link mechanism L1, and FIGS. 24 to 27 show the main lock mechanism 70 provided around the fulcrum Pd. 23 to 25, the vehicle body 2 is in use, and in FIG. 27, the vehicle body 2 is in a folded state. The main lock mechanism 70 is provided to restrain the vehicle body 2 in a use state and a folded state by preventing rotational movement between a pair of link parts included in the first link mechanism L1, Corresponds to the in-link locking mechanism.

  As described above, the link connecting component 23 for connecting the back frame 15 to the seat frame 7 is attached to the lower end portion of the back frame 15. As shown in FIG. 23, the link connection component 23 is fixed to the back frame 15 using a connection pin 71. A housing 23 a is formed at the lower part of the link connecting component 23. 24 to 27 show the main part of the main lock mechanism 70 with the link connecting component 23 removed. A link connecting part 72 is also provided at the rear end of the seat frame 7, and the link connecting part 72 is fixed to the seat frame 7 using a connecting pin 73. The link connecting component 72 is integrally formed with a guide shaft portion 72 a that fits inside the housing 23 a of the link connecting component 23. The guide shaft portion 72a and the housing 23a are rotatably connected via a connecting pin 74 on the fulcrum Pd, whereby the seat frame 7 and the back frame 15 are rotatably connected around the fulcrum Pd. A pair of receiving portions 72b and 72c are provided on the outer periphery of the guide shaft portion 72a with a distance in the circumferential direction. The receiving portion 72b faces the lower end portion of the back frame 15 when in use, and the receiving portion 72c faces the lower end portion of the back frame 15 when folded.

  Further, a lock member 75 is slidably inserted into the back frame 15. The lock member 75 is guided by the inner peripheral surface of the back frame 15 and the connecting pin 71, and the lock position shown in FIG. It can move between the retracted release positions (positions shown in FIGS. 25 and 26). When the lock member 75 is moved to the lock position when the vehicle body 2 is in use, the lock member 75 and the receiving portion 72b are engaged with each other as shown in FIG. 24, and the link connecting parts 23 and 72 are relatively moved around the fulcrum Pd. The vehicle cannot be rotated, so that the vehicle body 2 is restricted to the use state. As shown in FIG. 25, when the lock member 75 is pulled up to the release position and the vehicle body 2 is changed to the folded state, the lock member 75 relatively moves on the outer periphery of the guide shaft portion 72a as shown in FIG. . Then, when the lock member 75 is moved to the lock position in the folded state, as shown in FIG. 27, the lock member 75 meshes with the receiving portion 72c, and the link connecting parts 23 and 72 cannot be relatively rotated around the fulcrum Pd. Thereby, the vehicle body 2 is restrained in the folded state. The lock member 75 is similarly operated when switching from the folded state to the used state.

  Inside the back frame 15 is provided spring means (not shown) that pushes the lock member 75 toward the lock position. A wire 76 as a transmission means is attached to the upper end of the lock member 75. When the wire 76 is pulled upward, the lock member 75 moves from the lock position to the release position against the spring means. The wire 76 is routed to the operation unit 16 (see FIG. 1) at the upper end of the hand push frame 8 via the inside of the back frame 15.

(Configuration around the handle)
Next, the operation unit 16 and the handle 17 provided at the upper end portion of the hand pushing frame 8 will be described. As shown in FIG. 28, the operation unit 16 is provided with a housing 80. The handle 17 is formed so as to draw a flat loop that is long in the vehicle width direction, and a pair of attachment portions 17a disposed so as to sandwich the housing 80 in the vehicle width direction is provided at the lower end thereof. The upper end portion of the back frame 15 is inserted into the housing 80 through the attachment portion 17a. An end tube 81 is placed between the mounting portion 17a and the back frame 15. In the upper center of the handle 17, a grip portion 17 b for a user to grip is formed.

  FIG. 29 is a vertical sectional view showing the internal configuration of the mounting portion 17a, and FIG. 30 is a horizontal sectional view showing the internal configuration of the mounting portion 17a. As is apparent from these drawings, a handle folding mechanism 82 is provided on the attachment portion 17a. FIG. 31 is a perspective view showing the main part of the handle folding mechanism 82, and FIG. 32 is a perspective view showing the inside of the attachment part 17a with the back frame 15 omitted. In these drawings, only the handle folding mechanism 82 inside the one attachment portion 17a is shown, but the handle folding mechanism 82 having the same configuration is provided symmetrically in the vehicle width direction on the other attachment portion 17a.

  As is clear from FIGS. 29 to 32, the handle folding mechanism 82 is arranged on the outer periphery of the back frame 15, while being coaxially disposed on the outer periphery of the back frame 15. A slide gear 84 that is housed inside the mounting portion 17 a in a slidable and rotatable manner and that can mesh with the ring gear 83, and a coil spring 85 that presses the slide gear 84 so as to mesh with the ring gear 83. And a slider 86 disposed on the outer periphery of the mounting portion 17a. As shown in FIGS. 33 and 34, the slider 86 has a substantially U-shaped shape, and has one rotation transmission claw 86a and two thrust claws 86b on its inner periphery. ing. The attachment portion 17a is formed with a hole 17c through which these claws 86a and 86b are passed. The slider 86 is fitted on the outer periphery of the mounting portion 17a so that the claws 86a and 86b are inserted into the mounting portion 17a from the extraction window 17c. In the mounting portion 17a, the rotation transmission claw 86a is fitted to the slide gear 84 so as to be integrally rotatable in the circumferential direction, and the thrust claw 86b is fitted to the slide gear 84 so as not to be relatively displaceable in the axial direction (see FIG. 34).

  Accordingly, when the slider 86 is operated outward in the vehicle width direction along the mounting portion 17a, the slide gear 84 moves in the same direction on the back frame 15 and the slide gear 84 and the ring gear 83 are disengaged (see FIG. 35). . When the slider 86 is operated in the circumferential direction in this state, the mounting portion 17a and the slide gear 84 rotate integrally around the back frame 15, and thereby the inclination of the handle 17 with respect to the back frame 15 changes. 1 and 2, the back frame 15 and the handle 17 are arranged in a substantially straight line when viewed from the side of the vehicle body 2. However, as shown in FIG. 36A, the handle 17 is tilted backward from the back frame 15 in the horizontal direction. Further, as shown in FIG. 36B, the handle 17 can be folded back behind the back frame 15 until it is turned upside down. The handle 17 in FIG. 3 corresponds to the state in FIG. 36B. By folding the handle 17 in this way, the height of the stroller 1 when the vehicle body 2 is folded can be further reduced. In addition to the position shown in FIG. 36A or 36B, the inclination of the handle 17 can be appropriately set according to the user's preference. The minimum resolution of the tilt resolution is an angle corresponding to one pitch of the gears 83 and 84.

  As shown in FIG. 37, a remote control mechanism 90 is provided inside the housing 80. The remote operation mechanism 90 is for switching the position of the lock member 75 of the main lock mechanism 70 described above. The remote operation mechanism 90 is rotatably provided around the shaft 91a of the pulley 91, and the drive pin 91b on the pulley 91 is fitted with the operation claw 92a of the operation slider 92 protruding below the housing 80. A configuration in which the end of the wire 76 is fixed to the outer periphery is provided. When the operation slider 92 is pushed upward, the pulley 91 rotates around the shaft 91a, and along with the rotation, the wire 76 is wound around the outer periphery of the pulley 91 and the lock member 75 built in the left and right back frames 15 is incorporated. Is raised to the release position. A lock slider 93 is attached to the outer periphery of the housing 80. When the lock slider 93 is at the position shown in FIG. 37, the lock arm 93a of the lock slider 93 rides on the operation claw 92a of the operation slider 92, and the operation slider 92 cannot be pushed. When the lock slider 93 is operated in the direction of the arrow X in FIG. 37, the lock arm 93a and the operation claw 92a are disengaged, and the operation slider 92 can be pushed in.

  As described above, in this embodiment, the handle 17 is rotatably connected to the back frame 15, and the handle folding mechanism 82 and the operation members of the remote operation mechanism 90 (sliders 86, 92, 93), and the grip portion 17b of the handle 17 is provided at a position away from the operation portion 16. Therefore, the handle 17b can be positioned at the center in the vehicle width direction by eliminating the operation members of the handle folding mechanism 82 and the remote operation mechanism 90 from the grip 17b. Thereby, the user can easily grip the grip portion 17b at the center in the vehicle width direction, and a comfortable operation feeling can be obtained even when the stroller 1 is operated with one hand. Since it is not necessary to secure the grip portion 17b between the back frames 15, the degree of freedom in designing the layout of the operation members (sliders 86, 92, 93) of the handle folding mechanism 82 and the remote operation mechanism 90 is also increased.

(Front leg and front wheel mounting structure)
Next, the front leg 4 and the structure for attaching the front wheel 10 to the front leg 4 will be described. FIG. 38 is an enlarged view of the front leg 4 and the front wheel 10, and FIG. 39 is a view showing the front leg 4 and the front wheel 10 with the legrest 18 removed. As described above, the front leg 4 has a configuration in which the lower ends of the pair of front leg frames 9 are bundled. As is clear from FIG. 39, the lower end portion of the front leg frame 9 is coupled by a connecting pin 100 using a rivet or the like, and the front wheel 10 is attached to the coupled portion via a caster 101. As shown in FIG. 40, the caster 101 includes a caster holder 102, a caster main body 103 assembled below the caster holder 102, and a slider 104 arranged to overlap with the caster holder 102 and the front side of the caster main body 103. And.

  As shown in FIGS. 41 and 42, the caster holder 102 includes a cylindrical frame receiving portion 105 whose lower end side is narrowed down, and a bearing portion 106 that protrudes downward from the frame receiving portion 105. The frame receiving portion 105 is formed with a pin mounting hole 105a penetrating the caster holder 102 in the vehicle width direction. Rail grooves 106a extending in the vertical direction are formed on the left and right sides of the bearing portion 106, and two positioning recesses 106b and 106c are provided at a distance in the vertical direction behind the rail grooves 106a. As is apparent from FIG. 42, the bearing portion 106 is provided with a bearing hole 106 d that extends in the vertical direction and opens on the lower surface of the caster holder 102. The center line of the bearing hole 106 d corresponds to the turning center line of the caster 101.

  As shown in FIGS. 43 and 44, the caster main body 103 includes a bearing portion 108 and a wheel mounting portion 109 connected to the rear of the bearing portion 108. Rail grooves 108a extending in the vertical direction are formed on the left and right sides of the bearing portion 108, and tapered portions 108b are formed behind the rail grooves 108a. Furthermore, as shown in FIG. 40, the bearing portion 108 is provided with a bearing hole 108 c that extends in the vertical direction and opens on the upper surface of the bearing portion 108. The center line of the bearing hole 108 c also coincides with the turning center line of the caster 101. The taper portion 108b described above is inclined so that the upper end side is biased toward the rear (rightward in FIG. 43) of the caster body 103 relative to the lower end side. The wheel mounting portion 109 is formed with an axle mounting hole 109a that penetrates the caster body 103 in the left-right direction. The axle mounting hole 109a has a long hole shape extending in the vertical direction. The axle 10b (see FIGS. 1 and 39) of the front wheel 10 is rotatably supported by the caster 101 in a state in which the axle 10b (see FIGS. 1 and 39) is movable in the vertical direction inside the axle attachment hole 109a. An impact mitigation mechanism (not shown) for mitigating an impact input to the axle 10b is incorporated in the wheel mounting portion 109. The axle 10b is urged downward by the impact mitigating mechanism, and is displaced upward according to the load input from the front wheel 10.

  As shown in FIGS. 45 to 47, the slider 104 has a slider body 104a that is curved so as to constitute a part of a cylindrical body, and the bearing of the caster holder 102 is utilized by utilizing the elasticity of the slider body 104a. The configuration fits around the outer periphery of the portion 106. An operation flange 104b is provided at the upper end of the slider body 104a. A pair of guide rails 104c extending in the vertical direction is formed on the inner periphery of the slider body 104a. At both ends in the circumferential direction of the slider main body 104a, positioning convex portions 104d are provided so as to protrude toward the inner peripheral side of the slider main body 104a. Furthermore, a tapered portion 104e that meshes with the tapered portion 108b of the caster body 103 is formed on both sides of the lower end of the slider body 104a.

  Returning to FIG. 40, the caster holder 102 and the caster main body 103 are combined so as to be rotatable around the fulcrum pin 110 by inserting the fulcrum pin 110 into their bearing holes 106d (see FIG. 42) and 108c. The slider 104 is fitted to the outer periphery of the front surface of the bearing portion 106 of the caster holder 102 so that the guide rail 104c is engaged with the rail groove 106a. Between the both ends of the fulcrum pin 110 and the caster holder 102 and the caster main body 103, for example, a stopper is provided by fitting a snap ring to the fulcrum pin 110, for example. A flange may be provided at one end of the fulcrum pin 110 as a retaining means on either side of the caster holder 102 or the caster main body 103.

  As shown in FIG. 39, in the caster 101, the lower end portion of the front leg frame 9 coupled by the connecting pin 100 is inserted into the frame receiving portion 105 of the caster holder 102, and one of the pin mounting holes 105a is inserted. The connecting pin 107 is driven from the side through the front leg frame 9 to the opposite side of the pin mounting hole 105a to be connected to the lower end of the front leg 4. In this state, the caster holder 102 and the slider 104 are connected to the front leg 4 so as not to rotate in the circumferential direction. On the other hand, the caster main body 103 switches between a state in which the turning around the fulcrum pin 110 is permitted and a state in which the turning is prevented depending on the position of the slider 104.

  In other words, the slider 104 can move up and down along the rail groove 106a and cannot rotate relative to the caster holder 102 in the circumferential direction by engaging the guide rail 104c with the rail groove 106a of the caster holder 102. It is. The rail groove 108a of the caster body 103 is provided so as to be aligned with the rail groove 106a of the caster holder 102 when the front wheel 10 is directed in the straight direction, in other words, when the axle 10b of the front wheel 10 is aligned with the vehicle width direction. It has been. FIG. 48 shows a state in which the rail grooves 106a and 108a are aligned. In the state of FIG. 48, since the entire slider 104 is on the bearing portion 106 of the caster holder 102, the caster main body 103 can turn. However, when the slider 104 is operated downward from the state of FIG. 48, a part of the guide rail 104c of the slider 104 fits into the rail groove 108a of the caster main body 103, and the slider 104 is connected to the caster holder 102 and the caster as shown in FIG. The main body 103 is located so as to straddle between the bearing portions 106 and 108. As a result, the respective taper portions 108 b and 104 e of the caster body 103 and the slider 104 mesh with each other, and the caster body 103 cannot turn with respect to the caster holder 102. As a result, the front wheel 10 is constrained to face straight. That is, FIG. 48 corresponds to a state in which the turning of the front wheel 10 is permitted, and FIG. 49 corresponds to a state in which the turning of the front wheel 10 is prevented. 48, the convex portion 104d of the slider 104 engages with the upper concave portion 106b of the caster holder 102, and in the state of FIG. 49, the convex portion 104d engages with the lower concave portion 106c.

  In the state shown in FIG. 49, when torque about the fulcrum pin 110 is applied to the front wheel 10, a component force Fc is applied in the direction of pushing up the slider 104 along the axial direction of the fulcrum pin 110 between the tapered portions 108b and 104e. Occurs. When the component force Fc exceeds a predetermined limit, the convex portion 104 d of the slider 104 escapes from the concave portion 106 c of the caster holder 102 and the slider 104 is pushed up onto the bearing portion 106 of the caster holder 102. As a result, the caster body 103 can turn around the fulcrum pin 110. Therefore, the possibility of inconvenience such as deformation or breakage of the slider 104 due to the torque exceeding the limit acting on the slider 104 is eliminated.

  According to the structure of the front leg 4 described above, the pair of left and right front leg frames 9 are bundled at their lower end portions and coupled to each other by the connecting pin 100, and the bundled lower end portions are casters. Since it is inserted into the cylindrical frame receiving portion 105 of the holder 102 and fastened together with the caster holder 102, there are the following advantages. First, when the front leg 4 is composed of a single pipe material, it is necessary to bend the pipe of the material into a substantially U shape or V shape. On the other hand, in this embodiment, the left and right front leg frames 9 may be bent as separate parts, and the bending angle is small. Therefore, the front leg frame 9 can be easily manufactured.

  By bundling the lower end portions of the two front leg frames 9, a connecting portion with the casters 101 can be integrally provided at the lower end portions of the front legs 4, so that a connecting member for attaching the casters 101 is the front leg frame 9. There is no need to manufacture it as a separate part and join it to the front leg frame 9 by welding or the like. Thereby, it is easy to ensure the rigidity of the connecting portion between the front leg 4 and the caster 101, and the number of parts can be reduced. This is also advantageous for reducing the weight of the vehicle body 2. Further, the connecting portion of the caster holder 102 to the front leg 4 is a cylindrical frame receiving portion 105, and the lower end portion of the front leg frame 9 is inserted therein, so that the frame receiving portion 105 is configured in a flat plate shape. Thus, it is easy to ensure the rigidity of the frame receiving portion 105. Therefore, the caster holder 102 can be made of resin to reduce the weight, reduce the manufacturing cost, and the like.

(Body dimensions)
Next, a preferred dimension range of the vehicle body 2 will be described with reference to FIG. 50 shows a state in which the vehicle body 2 is in use and the handle 17 is positioned substantially in line with the longitudinal direction of the back frame 15 (hereinafter referred to as a reference state).

  In the stroller 1 of this embodiment, the front wheels 10 are attached to the vehicle body 2 via casters 101. For this reason, the vertical center line (vehicle turning center line) when the vehicle body 2 is turned by grasping the grip portion 17b of the handle 17 is located on the rear wheel axis Aw (see FIG. 6B) with respect to the longitudinal direction of the vehicle body 2. . Assuming that the power point when operating the stroller 1 is at the center (hereinafter referred to as the grip center) Cg of the grip portion 17b of the handle 17, the longitudinal distance Xc between the grip center Cg and the rear wheel axis Aw is set. On the other hand, as the longitudinal distance Xb between the back seat intersection Ci of the seat 3 and the rear wheel axis Aw is smaller and the inter-axis distance Xa between the wheels 10 and 11 is shorter, the grip portion 17b is used to turn the vehicle body 2. The force (hereinafter referred to as the turning operation force) to be applied to is reduced. That is, the smaller the ratio of the distances Xa and Xb to the distance Xc, the smaller the turning operation force. Here, the back seat intersection point Ci is an extension line drawn along the surface of the cushion portion 12 of the seat 3 when the vehicle body 2 is viewed from the rear wheel axis Aw direction, and an extension drawn along the surface of the back portion 13. This is the point where the line intersects. The position of the center of gravity of the infant's weight acting on the seat 3 can be represented by the back seat intersection Ci.

  Further, the smaller the ratio of the height Za of the back seat intersection point Ci to the height Zb of the grip center Cg, the more advantageous the operability of the vehicle body 2, and the smaller the height Za of the back seat intersection point Ci is the stability of the vehicle body 2 This is also advantageous in securing the property. On the other hand, if the distance Xc is set large and the distances Xa and Xb are set small, the stability of the vehicle body 2 in the vehicle width direction is lowered, and this tendency is particularly high in the case of the three-wheel type.

  Considering the above circumstances, it is reasonable to reduce the turning operation force and to ensure the stability of the vehicle body 2 by increasing the inter-axis distance Xa and decreasing the height Za of the back seat intersection Ci. It is. Therefore, in this embodiment, each dimension is set as follows.

(1) The distance Xc between the grip center Cg and the rear wheel axis Aw is less than 2Xc, and the distance Xb between the back seat intersection Ci and the rear wheel axis Aw is 0.4Xc to Each is set in the range of 0.6Xc. If the inter-axis distance Xa is 2Xc or more, the turning operation force may be excessively increased. When the distance Xb is less than 0.4Xc, the back seat intersection Ci is too close to the rear wheel axis Aw and the vehicle body 2 tends to tilt backward, and when the distance Xb exceeds 0.6Xc, the turning investigation force becomes excessively large. There is a fear.

(2) The height Za of the back seat intersection Ci is set to be less than 0.32 Zb with respect to the height Zb of the grip center Cg. If the height Za is 0.32 Zb or more, the stability of the vehicle body 2 may be deteriorated beyond the limit.

  Note that the stability of the vehicle body 2 can also be ensured by increasing the distance Da between the rear wheels 11 in use. However, if the rear wheel 11 is expanded indefinitely, the passage width through which the vehicle body 2 can pass is limited, and the usability may be deteriorated. As one guideline, the maximum distance Da in the vehicle width direction of the rear wheel 11 may be set to less than 550 mm. If it is less than 550 mm, even if it is a narrow place such as a passage of an automatic ticket gate, it can pass sufficiently with the rear wheel 11 spread.

  When the cushion portion 12 and the back portion 13 of the seat 3 are curved, the back seat intersection Ci is extended by extending the flat portion if the cushion portion 12 and the back portion 13 are left flat. The intersection point Ci may be defined. When there is no clear plane portion, or the cushion portion 12 and the back portion 13 are covered with a non-removable cushion material or skin material, or there is no substrate in the cushion portion 12 and the back portion 13 that should be a core material. If the back seat intersection Ci cannot be defined due to the above reasons, the SG standard (Standard No. CPSA0001) “Accreditation Standards for Strollers and Standard Checking Method” by the Foundation for Product Safety, or the British Standard EN1888: 2003 A jig for measuring the angle between the seating surface and the backrest is installed on the seat 3, and the surfaces where the jig contacts the seat cushion portion 12 and the seat back portion 13 are extended from the side of the vehicle body. What is necessary is just to determine those intersections as the back seat intersection Ci.

  In the stroller 1 of the present embodiment, the angle of the handle 17 can be changed with respect to the back frame 15 of the hand push frame 8, so that the above requirements (1) and (2) are satisfied in the above-described reference state. The dimension of the vehicle body 2 is set to When the inclination of the handle 17 changes from the reference state, there may be a case where at least one of the requirements (1) and (2) is not satisfied. However, the requirements (1) and (2) are for achieving both stability and operability when the vehicle body 2 is turned. For example, when the vehicle body 2 is merely moved forward, Without being constrained by (2), the inclination of the handle 17 may be appropriately adjusted according to the user's extension, preference, and the like. That is, in the stroller in which the tilt of the handle can be adjusted as in this embodiment, the requirements (1) and (2) are satisfied when the handle is set to any tilt within the adjustment range. It is enough.

The present invention is not limited to the above-described form and can be implemented in various forms. For example, in the above embodiment, the slider 104 as the lock member is provided on the outer periphery of the caster holder 102, but the lock member may be accommodated in the caster holder 102. As guide means for the lock member, the guide rail 104e is provided on the slider 104 and the rail groove 106a is provided on the caster holder 102. However, the guide rail may be provided on the caster holder and the rail groove may be provided on the lock member. The guide means may be appropriately changed, for example, constituted by a pin extending in the direction of the turning center line and a pin hole into which the guide means fits. Although the protrusion 104e is provided on the slider 104 as the lock member and the recess 106c is provided on the caster holder 102, the recess may be provided on the lock member and the recess may be provided on the caster holder . When lock member is in the locked position (position of FIG. 49), if it can hold the lock member without engaged and the concave portion and the convex portion in the locked position with moderate force, and their recesses and projections May be omitted. In the above-described embodiment, the stroller is a three-wheeled type including a single front wheel disposed at the center in the vehicle width direction and a pair of rear wheels disposed on both sides in the vehicle width direction. It can also be applied to a four-wheel baby stroller. The caster of the present invention may be applied not only to the front wheel but also to the rear wheel. Furthermore, the caster of the present invention is not limited to the example attached to the leg portion (front leg or rear leg) of the stroller, but various kinds of casters as long as it is necessary to switch between the state of preventing the wheel from turning and the state of allowing the turning. Applicable to wheel support structure.

1 is a perspective view of a stroller according to an embodiment of the present invention. The side view which shows the structure in the use condition of the left-right direction (vehicle width direction) one side of a vehicle body. The side view when changing a vehicle body into a folded state. The figure which divided the mode which changed the vehicle body from a use state to a folding state in several steps. The mechanism figure which simplified the 1st link mechanism. The side view which shows the relationship between a front leg and a rear leg when a vehicle body is in use condition. The figure which shows the state which looked down the left and right rear legs when the vehicle body is in use along the longitudinal direction of the front leg frame. The side view which shows the relationship between the front leg and the rear leg when the vehicle body is in a folded state. The figure which shows the state which looked down the left and right rear legs when the vehicle body is in the folded state along the longitudinal direction of the front leg frame. The figure which expands and shows the vicinity of a connection rod. The enlarged view of a ball joint. The perspective view which shows a mode that the ball joint was looked up from the downward direction. Sectional drawing along the XI-XI line of FIG. The figure which shows the state which abbreviate | omitted the ball housing corresponding to FIG. The perspective view which shows a mode that the ball joint cap of the ball joint was looked up from the downward direction. Sectional drawing which shows the state which abbreviate | omitted the ball housing corresponding to FIG. The perspective view of a ball housing. Sectional drawing of a universal joint. The perspective view which shows the locked state of the 2nd lock mechanism which concerns on one form. The perspective view which shows the cancellation | release state of the 2nd lock mechanism which concerns on one form. The perspective view which shows the locked state of the second lock mechanism which concerns on another form. The perspective view which shows the cancellation | release state of the 2nd lock mechanism which concerns on another form. The perspective view which shows the state which looked at the rear-wheel carrier from the vehicle width direction inner side. The figure which shows the internal structure of a rear-wheel carrier. The figure which expands and shows the structure of the vicinity of the fulcrum of the seat frame and back frame in a 1st link mechanism. The figure which shows the main lock mechanism when the vehicle body is in use and rotation between the seat frame and the back frame is restricted. The figure which shows the state which operated the lock member to the cancellation | release position from FIG. The figure which shows the main lock mechanism in the middle of rotating the seat frame and a back frame between a use state and a folding state. The figure which shows the main lock mechanism when the vehicle body is in a folded state and the rotation between the seat frame and the back frame is restricted. The perspective view which expands and shows the operation part and handle which were provided in the upper end part of the hand pushing frame. The vertical direction sectional view showing the composition inside a handle attachment part. The horizontal direction sectional view which shows the internal structure of a handle | steering-wheel attachment part. The perspective view which shows the principal part of a handle folding mechanism. The perspective view which abbreviate | omitted the back frame and showed the inside of the attaching part. The figure which shows a mode that the slider and slide gear of a handle folding mechanism are assembled | attached to the attaching part of a handle. The perspective view which shows the state which combined the slider and slide gear of the handle folding mechanism. The figure which shows the state which cancelled | released meshing | engagement of a ring gear and a slide gear. The figure which shows a mode that the handle | steering-wheel was knocked down substantially horizontally. The figure which shows a mode that the handle | steering-wheel turned upside down. The figure which shows the remote control mechanism provided in the operation part of the hand pushing frame. The figure which expanded and showed the front leg and the front wheel. The figure which removed the leg rest and showed the front leg and the front wheel. The disassembled perspective view of a caster. The right view of a caster holder. The bottom view of a caster holder. The right view of a caster main part. The top view of a caster main body. The right view of a slider. The rear view of a slider. The top view of a slider. The figure which shows the state of a caster when turning of a front wheel is permitted. Rider The figure which shows the state of the caster when turning of a front wheel is blocked | prevented. The figure which shows the dimension of each part of a vehicle body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Stroller 2 Car body 3 Seat 4 Front leg 5 Rear leg 6 Armrest 7 Seat frame 8 Hand push frame 9 Front leg frame 10 Front wheel 10a Tire 10b Axle 11 Rear wheel 11a Axle 12 Seat cushion part 13 Seat back part 14 Hinge part 15 Back frame 16 Operation part 17 Handle 17a Handle mounting portion 17b Grip portion 18 Leg rest 22 Seat frame bracket 23 Link connecting component 25 Upper arm 26 Lower arm 27 Rear leg bracket 28 Rear wheel carrier 30 Connecting rod 31 Rear leg stay 32 Fixing device 35 Ball joint 36 Universal Joint 50 Extension arm 51 Seat stay 52 Second lock mechanism (inter-link lock mechanism)
60 Carrier body 61 Bearing block 63 Cushion member (impact buffering means)
70 Main lock mechanism 72 Link connection part 75 Lock member 76 Wire 80 Housing 81 End tube 82 Handle folding mechanism 83 Ring gear 84 Slide gear 85 Coil spring 86 Slider 90 Remote control mechanism 100 Connection pin 101 Caster 102 Caster holder 103 Caster body 104 Slider 104c guide rail 104e taper part 105 frame receiving part 106 bearing part 106a rail groove 107 connecting pin 108 bearing part 108a rail groove 108b taper part 110 fulcrum pin Aq rear leg arm rotation center line Aw rear wheel axis line CL longitudinal center line of the vehicle body Cg Grip center Ci Back seat intersection L1 First link mechanism L2 Second link mechanism Xa Center distance Xb Distance between back seat intersection and rear wheel axis Xc Grip center Distance between the front and rear wheels and the axis of the rear wheel Za Height of the back seat intersection Zb Height of the grip center

Claims (7)

A caster body to which wheels are attached;
A caster holder that rotatably supports the caster body about a turning center line orthogonal to the axis of the wheel;
A lock position that engages with the caster body around the turning center line so as not to rotate relative to the caster body, and moves back toward the caster holder along the turning center line from the lock position to release the engagement with the caster body. A locking member which is movable between a release position and is attached to the caster holder in a state in which it is not rotatable relative to the caster holder around the turning center line;
In the meshing portion of the lock member and the caster body, the torque around the turning center line input to the caster body is converted into a force in a direction from the lock position toward the release position, and the lock member tapered portion to act is provided,
A caster , characterized in that a recess and a projection are provided between the caster holder and the lock member that mesh with each other when the lock member is in the release position .   The caster according to claim 1, wherein guide means for guiding the lock member in the direction of the turning center line is provided between the caster holder and the lock member.   The guide means is provided on one of the caster holder or the lock member and extends in the direction of the turning center line, and is provided on the other of the caster holder or the lock member and the guide rail. The caster according to claim 2, further comprising a rail groove that meshes with the caster.   4. A recess and a projection that mesh with each other when the lock member is in the lock position are provided between the caster holder and the lock member. Casters described in   The caster according to any one of claims 1 to 4, wherein the lock member is fitted to an outer periphery of the caster holder using elasticity.   A stroller comprising the caster according to any one of claims 1 to 5, wherein the caster holder of the caster is connected to a leg portion.   A three-wheel structure having a single front wheel disposed in the center in the vehicle width direction and a pair of rear wheels disposed on both sides in the vehicle width direction, and the front wheel is attached to the front leg via the casters The stroller according to claim 6, wherein the stroller is provided.

Images