HK1243683B - Baby carriage - Google Patents

Description

baby carriage

Technical Field

The present invention relates to a baby carriage whose wheels are driven by a driving source.

Background Art

For example, Japanese Patent JP2011-68336A discloses a baby stroller with an electric motor. In the baby stroller described in JP2011-68336A, pressing a control lever drives the electric motor connected to the wheels. Specifically, the baby stroller described in JP2011-68336A automatically moves using the electric motor. In other words, the baby stroller described in JP2011-68336A can move independently, even without being pushed by an operator, using only the driving force of the electric motor.

Summary of the Invention

Technical issues

When the stroller is parked, the wheel locking device is operated to maintain the wheel's rotation restricted. However, in the stroller described in Japanese Patent JP2011-68336A, if the control lever is pressed while the wheel's rotation is restricted by the wheel locking device, the electric motor is driven. If the electric motor attempts to drive the wheel while its rotation is restricted, it cannot do so because the wheel is locked, resulting in an excessive load on the electric motor.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a baby carriage that suppresses an excessive load from being applied to a driving source in a state where the rotation of the wheels is restricted by a wheel locking device.

Technical Solution

The baby stroller of the present invention comprises:

Baby stroller body;

a plurality of wheels supported by the stroller body and rotatable about respective rotation axes;

a driving source supported by the stroller body and providing driving force to at least one of the plurality of wheels;

a detection element for detecting information related to the movement operation input into the stroller body;

a control device for controlling the drive source based on the information detected by the detection element to adjust the driving force provided from the drive source to the wheels;

The wheel locking device is provided on the stroller body in a manner capable of switching between a locked state and a released state, wherein the locked state is a state in which at least one of the plurality of wheels is restricted from rotating about its own rotation axis, and the released state is a state in which the state in which the rotation of the wheel is restricted is released.

While the wheel locking device is in the locked state, the driving force from the driving source is not transmitted to the wheel.

Optionally, the baby stroller of the present invention further comprises: a locking sensor for detecting the state of the wheel locking device, and the control device performs control in such a manner that the driving force from the driving source is not transmitted to the wheels while the wheel locking device is detected by the locking sensor to be in the locked state.

Optionally, in the stroller of the present invention, the wheel locking device includes: an operating member movable between a locked position and a released position; and a locking member connected to the operating member via a connecting member, wherein the locking member engages with the wheel to restrict rotation of the wheel about its own rotation axis while the operating member is in the locked position, and moves away from the wheel to release the wheel's restriction while the operating member is in the released position. Furthermore, the stroller may further include a lock sensor to detect the position of the operating member, and the control device controls the wheel so that the driving force from the drive source is not transmitted to the wheel while the lock sensor detects that the operating member is in the locked position.

Optionally, in the baby stroller of the present invention, the wheel locking device at least restricts the wheel driven by the driving source from rotating around its own rotation axis in the locked state.

Optionally, in the baby stroller of the present invention, the wheel among the plurality of wheels to which the driving force is provided by the driving source is a rear wheel, and the front wheel among the plurality of wheels is supported on the baby stroller body via casters.

Optionally, in the stroller of the present invention, the stroller body includes a frame body supporting the plurality of wheels and a handle connected to the frame body, wherein the detection element is disposed on the handle and detects information related to a load applied to the handle.

Effects of the Invention

According to the present invention, when the wheel rotation is restricted by the wheel locking device, the driving force from the drive source is not transmitted to the wheel. This prevents the drive source from driving the wheel while the wheel rotation is restricted, thus preventing excessive load from being applied to the drive source. Furthermore, the driving force exerted by the drive source on the wheel can be adjusted in conjunction with the stroller's travel operation, allowing the stroller to be operated as desired.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view showing a baby stroller according to one embodiment in an expanded state.

FIG. 2 is a side view showing the baby stroller in the expanded state shown in FIG. 1 with the seat unit removed.

FIG. 3 is a side view showing the baby carriage shown in FIG. 2 in a folded state.

FIG. 4 is a block diagram schematically showing the configuration of the baby carriage shown in FIG. 1 .

FIG. 5 is a perspective view showing the driving elements and wheels of the baby carriage shown in FIG. 1 from the rear.

FIG6 is a circuit diagram showing the connection relationship of the DC motor constituting the driving element.

FIG. 7 is an enlarged plan view showing the handle of the baby stroller shown in FIG. 1 .

FIG. 8 is a diagram for explaining the configuration of a detection element provided on the handle of the baby carriage shown in FIG. 1 .

FIG9 is a circuit diagram of the detection element shown in FIG8.

FIG. 10 is a graph showing an example of adjusting the driving force of the driving element based on information from the detection element.

FIG. 11 is a perspective view showing the wheel locking device provided on the stroller shown in FIG. 1 in a released state.

FIG. 12 is a perspective view showing the wheel locking device provided on the stroller shown in FIG. 1 in a locked state.

FIG. 13 is an enlarged perspective view showing a portion of the wheel locking device shown in FIG. 11 .

FIG14 is a side view of the wheel locking device shown in FIG12 as seen from the side.

FIG. 15 is a diagram for explaining the function of the detection element when the handle of the baby carriage shown in FIG. 1 is pushed forward.

FIG. 16 is a diagram for explaining the operation of the detection element when the handle of the baby carriage shown in FIG. 1 is pressed down and when the baby carriage is going down a slope.

FIG. 17 is a diagram for explaining the function of the detection element when the handle of the baby carriage shown in FIG. 1 is pulled backward.

FIG. 18 is a perspective view for explaining a state in which the baby carriage shown in FIG. 1 is turned.

FIG19 is a perspective view showing another example of a drive wheel.

FIG. 20 is a perspective view showing the configuration of a wheel locking device provided in the stroller shown in FIG. 19 .

FIG21 is a side view showing, in an enlarged manner, a locking member constituting the left side of the wheel locking device shown in FIG19.

FIG. 22 is a side view showing the left locking member shown in FIG. 21 in a state where the wheel is locked.

DETAILED DESCRIPTION

An embodiment of the present invention will be described below with reference to the accompanying drawings. Figures 1 to 22 illustrate a baby stroller 1 according to one embodiment. Figure 1 shows the baby stroller 1 according to one embodiment from the front. In the baby stroller 1 shown in Figure 1 , a first seat unit 8a and a second seat unit 8b are supported by the stroller body 2. The first and second seat units 8a and 8b are positioned side by side, providing seating for the infant. Canopies 9a and 9b are provided on each seat unit 8a and 8b to protect the infant from sunlight and wind.

It should be noted that, in this specification, the terms "front," "rear," "up," "down," "front-back direction," "upper-lower direction," and "left-right direction" with respect to the stroller 1 and its components, unless otherwise specified, refer to the "front," "rear," "up," "down," "front-back direction," "upper-lower direction," and "left-right direction" relative to an operator operating the stroller 1 in its unfolded state while gripping the handle 20. More specifically, the "front-back direction d1" corresponds to the front-to-back direction relative to the paper in Figure 1 . Furthermore, unless otherwise specified, "front" refers to the side facing the operator pushing the handle, with the outer side of the paper in Figure 1 being the front. Meanwhile, the "upper-lower direction d3" refers to a direction perpendicular to the front-to-back direction and to the ground contact surface. Therefore, when the ground contact surface is horizontal, the "upper-lower direction d3" refers to the vertical direction. Furthermore, the "left-right direction d2" refers to the width direction and is perpendicular to both the "front-to-back direction d1" and the "upper-lower direction d3."

FIG2 shows the baby carriage 1 from the side with the seat units 8a and 8b removed. The baby carriage body 2 shown in FIG2 is composed of a frame body 10 and a handle 20 connected to the frame body 10.

In the frame body 10, an upper frame 12 supporting the two seat units 8a and 8b is connected to a base frame 11 supporting the multiple wheels 4. The upper frame 12 is supported in an inclined position relative to the base frame 11. The front portion of the upper frame 12 is connected to the front portion of the base frame 11 via a front connecting member 13, and the middle portion of the upper frame 12 is connected to the rear portion of the base frame 11 via an intermediate connecting member 14. The front connecting member 13 and the intermediate connecting member 14 serve as a connection and enable the upper frame 12 to rotate relative to the base frame 11.

Specifically, the base frame 11 includes left and right side base frames 11a and 11b, spaced apart in the left-right direction d2. The rear ends of the left and right side base frames 11a and 11b are connected by a rear base frame 11c. In this embodiment, the left and right side base frames 11a and 11b and the rear base frame 11c are integrally formed by bending a single pipe. However, the left and right side base frames 11a and 11b and the rear base frame 11c may also be formed as separate components.

A front wheel 41 and a rear wheel 42 are mounted on each side base frame 11a, 11b. In this embodiment, each front wheel 41 is supported by the side base frames 11a, 11b via a caster 3 so that it can rotate and steer. The caster 3 supports the front wheel 41 so that it can rotate about the rotation axis Ar1 and can steer about a steering axis that is not parallel to the rotation axis Ar1. In this embodiment, the steering axis As1 is parallel to the direction perpendicular to the rotation axis Ar1. In other words, the front wheel 41 is supported by the caster 3 so that it can rotate and change direction.

On the other hand, each rear wheel 42 located behind the front wheel 41 is not steerably supported by a caster. In this embodiment, each rear wheel 42 is rotatably supported by a drive shaft 51a (see FIG. 5 ) of a drive source 5 described later, but is not steerable.

The upper frame 12 includes left and right side upper frames 12a and 12b spaced apart in the left-right direction d2. An intermediate frame 12c is disposed between the left and right side upper frames 12a and 12b. In this embodiment, the first seat unit 8a is disposed between the left side upper frame 12a and the intermediate frame 12c, and the second seat unit 8b is disposed between the right side upper frame 12b and the intermediate frame 12c.

The rear ends of the left and right side upper frames 12a and 12b and the center frame 12c are connected by a rear upper frame 12d. A handle 20 is mounted on the rear upper frame 12d. The handle 20 is the part that the operator operates with his hands. The handle 20 will be described later with reference to Figures 7 to 10.

In the illustrated example, the left and right side upper frames 12a, 12b and the rear upper frame 12d are integrally formed by bending a single pipe. However, the left and right side upper frames 12a, 12b and the rear upper frame 12d may be formed as separate components.

The front ends of the left and right upper side frames 12a and 12b are connected to the upper side connecting frame 13a via a transverse link 12e. The transverse link 12e is formed linearly along the left-right direction d2, and the front end of the intermediate frame 12c is connected to the middle portion of the transverse link 12e.

The upper connecting frame 13a serves as a connector and has a curved shape that protrudes forward from the transverse link 12e. Furthermore, a base connecting frame 13b is mounted between the front portion of the upper connecting frame 13a and the front ends of the left and right side base frames 11a and 11b. The front end of the base connecting frame 13b is fixed to the upper connecting frame 13a, while its left and right rear ends are rotatably connected to the left and right side base frames 11a and 11b via transverse connecting links 13c. The transverse connecting links 13c are formed in a straight line along the left-right direction d2 and are rotatably connected to the front ends of the left and right side base frames 11a and 11b. The upper connecting frame 13a, the base connecting frame 13b, and the transverse connecting links 13c constitute the front connecting member 13, which serves as a connector.

It should be noted that the left and right intermediate connecting members 14 are mounted between the intermediate portions of the left and right side upper frames 12a, 12b and the rear portions of the left and right side base frames 11a, 11b. Each intermediate connecting member 14 serves as a connection and is rotatable relative to both the side upper frames 12a, 12b and the side base frames 11a, 11b.

The baby carriage 1 having the above-described frame structure can be folded from the unfolded state shown in Figures 1 and 2 to the folded state shown in Figure 3. Figure 3 is a side view showing the baby carriage 1 shown in Figure 2 in the folded state.

First, the locks between the side upper frames 12a, 12b and the upper side connecting frame 13a are released, and the handle 20 is lowered by its own weight. This action causes the upper side connecting frame 13a, the base side connecting frame 13b, and the intermediate connecting member 14 to rotate counterclockwise in Figure 2, so that the upper frame 12 overlaps the base frame 11.

The result of the above folding operation is shown in FIG3 , where the base frame 11 and upper frame 12 are positioned close together and approximately parallel to each other in a side view of the stroller 1. On the other hand, to return the stroller 1 from the folded state shown in FIG3 to the unfolded state shown in FIG2 , the above folding operation can be performed in the reverse order.

In the stroller 1 of this embodiment, a drive source 5 is connected to the wheels 4 to reduce the operator's burden. However, as described in the Background Art section, conventional strollers are so-called self-propelled, making it difficult to operate the stroller as intended. Therefore, the stroller 1 of this embodiment is configured as an auxiliary drive hand-push stroller that provides driving force to the wheels 4 in response to the operator's travel operation.

Figure 4 schematically illustrates a block diagram of the mechanism for assisting the driving of the wheels 4. As shown in Figure 4 , drive elements 51 and 52 are connected to several of the multiple wheels 4. Drive elements 51 and 52 are components that drive the wheels 4; in other words, they provide driving force to the wheels 4. In this embodiment, two drive elements are provided: a first drive element 51 and a second drive element 52. The first drive element 51 drives the left rear wheel 42, and the second drive element 52 drives the right rear wheel 42.

FIG5 shows an example of the structure of the drive elements 51 and 52. As shown in FIG5, each drive element 51 and 52 is composed of a drive shaft 51a and 52a connected to the rear wheel 42 on the corresponding side and a DC motor 51b and 52b that drives the drive shaft 51a and 52a. One end of the drive shaft 51a and 52a is connected to the rear wheel 42 on the corresponding side, and the rear wheel 42 is supported in a manner that can rotate around the rotation axis Ar2 as the center, but not in a manner that can turn. The other end of the drive shaft 51a and 52a is connected to the main shaft of the DC motor 51b and 52b via a power transmission element (such as a gear) not shown in the figure. It should be noted that the drive shaft 51a and 52a can be integrally formed with the main shaft of the DC motor 51b and 52b, or can be constructed as a separate component.

The DC motors 51b and 52b are located within a storage box 70 mounted on the left and right side base frames 11a and 11b, and are supported by the side base frames 11a and 11b within the storage box 70. FIG6 shows a circuit diagram illustrating the connection relationship between the DC motors 51b and 52b. As shown in FIG6, the DC motors 51b and 52b of the two drive elements 51 and 52 are connected in series with respect to a power source 75. Connecting the two DC motors 51b and 52b in series facilitates adjusting the driving force according to the load applied to the ground surface, a point described later.

Returning to Figure 4, each drive element 51, 52 is connected to the control device 7 and is controlled by the control device 7. The control device 7 is also connected to the detection element 6 and obtains information from the detection element 6 as input. In addition, the control device 7 controls each drive element 51, 52 based on the information from the detection element 6, and adjusts the driving force provided from each drive element 51, 52 to the wheel 4. In addition, the control device 7 is connected to a power supply 75 that is detachably fixed to the storage box 70. Such a control device 7 can be implemented in the form of a microcontroller and/or a programmable controller (PLC) having a central processing unit (CPU) and a register (REGISTER).

The detection element 6 is used to detect information related to the running operation input into the stroller body 2. The information related to the running operation detected by the detection element 6 is not particularly limited, as long as it is information input into the stroller body 2 by the operator. Examples of information related to the running operation include information related to the load applied by the hand operating the handle 20 and information related to the rotational speed of the wheels 4, which is related to the speed at which the operator is causing the stroller 1 to run.

Returning to FIG2 , the detection element 6 of this embodiment is provided on the handle 20 and is configured to detect information related to the load applied to the handle 20. In other words, it is configured to determine information about the load applied to the handle 20. First, the configuration of the handle 20 will be described, followed by a description of the detection element 6 provided therein.

FIG7 shows an enlarged view of the handle 20. As shown in FIG7 , the handle 20 is provided with a grip 21 for the operator's hand to rest on, and a handle body 22 connects the handle 21 to the stroller body 2. The handle body 22 is connected to the upper frame 12 at a connection position c1.

Specifically, a column 22a extends from the rear upper frame 12d, and side bars 22b and 22c are disposed on either side of the column 22a. The handle 21 is constructed as two handle portions 21a and 21b spaced apart in the left-right direction d2. The left handle portion 21a is positioned between the left side bar 22b and the column 22a, while the right handle portion 21b is positioned between the right side bar 22c and the column 22a.

FIG8 shows an enlarged view of the detection element 6 provided in the column 22a, and FIG9 shows a circuit diagram of the detection element 6. As shown in FIG8 and FIG9, a plurality of strain gauges 61 serving as the detection element 6 are attached to the inner square member 22d in the column 22a. The plurality of strain gauges 61 form a bridge circuit to measure the deformation of the handle body 22. In the example shown in FIG8, two strain gauges 61 are arranged on the upper surface of the square inner square member 22d, and two strain gauges 61 are arranged on the lower surface of the inner square member 22d, and these four strain gauges 61 are identical in structure to each other. It should be noted that the inner square member 22d shown in the figure is hollow, but it can also be solid.

FIG10 is a graph illustrating an example of controlling the driving force provided by driving elements 51 and 52 based on the deformation detected by strain gauge 61. In the graph of FIG10 , the horizontal axis represents the deformation detected by strain gauge 61, with positive values indicating an extension of strain gauge 61 attached to the upper surface of inner member 22d or a contraction of strain gauge 61 attached to the lower surface of inner member 22d, and negative values indicating a contraction of strain gauge 61 attached to the upper surface of inner member 22d or an extension of strain gauge 61 attached to the lower surface of inner member 22d. The vertical axis represents the driving force driving wheel 4, with positive values indicating a driving force rotating wheel 4 in the forward direction and negative values indicating a driving force rotating wheel 4 in the reverse direction.

As shown in FIG10 , when the magnitude of the strain detected by the strain gauge 61 is less than the lower limit value α1, the control device 7 controls the wheels 4 so that the driving force generated by the drive elements 51 and 52 is not supplied. This prevents the stroller 1 from unintentionally moving even if interference or unintentional operation is applied to the stroller 1.

If the magnitude of the strain detected by the strain gauge 61 exceeds the lower limit value α1, the control device 7 controls the driving elements 51 and 52 so that the driving force generated is provided to the wheel 4 in proportion to the magnitude of the strain detected by the strain gauge 61. In the graph of FIG10 , when the strain gauge 61 is extended, the driving force is provided to rotate the wheel 4 in the forward direction, and when the strain gauge 61 is contracted, the driving force is provided to rotate the wheel 4 in the backward direction.

On the other hand, if the magnitude of the strain applied to the handle 20 becomes larger than the upper limit value α2 , the control device 7 controls so that the driving force generated by the driving elements 51 , 52 is supplied to the wheel 4 as the upper limit driving force F.

When the stroller 1 having such a drive mechanism is parked, the wheel locking device 80 shown in FIG5 is operated to maintain the locked state of the wheels 4. The wheel locking device 80 that locks the wheels 4 will be described below with reference to FIG11 and FIG12 . FIG11 is a perspective view of the wheel locking device 80 in the released state S2, in which the rotation restriction of the wheels 4 is released. FIG12 is a perspective view of the wheel locking device 80 in the locked state S1, in which the rotation of the wheels 4 is restricted.

11 and 12 , the wheel locking device 80 is used to lock at least one wheel 4, that is, to restrict at least one wheel 4 from rotating about the rotation axis Ar2. The wheel locking device 80 can be switched between a locked state S1 shown in FIG12 and a released state S2 shown in FIG11 .

An operating member 81 constituting the wheel locking device 80 is disposed around the rear base frame 11c. A locking member 85 is connected to the operating member 81 via a connecting member 82. In this embodiment, one locking member 85 is provided on each side to restrict the rotation of the rear wheel 42 on the side to which each locking member 85 corresponds.

The operating member 81 is an operator-operated component that restricts the rotation of the wheel 4. Mounting frames 11d are mounted on the left and right side base frames 11a and 11b, and the operating member 81 is steerably supported on these mounting frames 11d via other components. Mounting frames 11d are located below the storage box 70 shown in Figure 5 , and the majority of the operating member 81, supported by mounting frames 11d, is housed within the storage box 70.

FIG13 shows an enlarged view of the wheel locking device 80 shown in FIG11 . As shown in FIG13 , the operating member 81 includes a guide wall 81a fixed to the mounting frame 11d, along which a rotating body 81b slides. Rotating body 81b includes a rotating body body 81c guided by the guide wall 81a, and an operating lever 81d extending rearward from the rotating body body 81c. The operating lever 81d is manually operated by the operator.

In this embodiment, the guide wall 81a is arranged along an arcuate path, and the outer edge of the rotor body 81c is also formed along the arcuate path. Therefore, when the operating lever 81d is switched between the position shown in Figure 11 and the position shown in Figure 12, the rotor body 81c is guided along the guide wall 81a and turns.

On the other hand, an extension piece 81e extends forward from the rotating body 81c. A connecting member 82 is connected to the front end of the extension piece 81e via a fulcrum pin 83. This fulcrum pin 83 is fixed to the mounting frame 11d via other components. Therefore, the operating member 81 rotates around the fulcrum pin 83 between the locked position P1 shown in Figure 12 and the released position P2 shown in Figure 11.

The connecting member 82 is a member that moves the left and right locking members 85 in conjunction with the movement of the operating member 81. The connecting member 82 comprises a link 82a, one end of which is pivotally connected to an extension piece 81e of the operating member 81. A left connecting arm 82b is connected to one end of the link 82a. Meanwhile, a right connecting arm 82c is connected to the other end of the link 82a.

It should be noted that the left connecting arm 82b is connected to one end of the connecting rod 82a, and the right connecting arm 82c is connected to the other end of the connecting rod 82a. Therefore, when the connecting rod 82a rotates in conjunction with the movement of the operating member 81, the left and right connecting arms 82b and 82c move in opposite directions in the left-right direction d2. Specifically, when the left connecting arm 82b is pushed to the left, the right connecting arm 82c is pushed to the right, and when the left connecting arm 82b is pulled to the right, the right connecting arm 82c is pulled to the left. This allows the left and right connecting arms 82b and 82c to be pushed out or pulled in simultaneously in conjunction with the operation of the operating member 81.

Each connecting arm 82b, 82c is partially bent and extended, and a locking member 85 is attached to its front end. The locking member 85 is a member that selectively engages the wheel 4 and restricts the rotation of the wheel 4 about the rotation axis Ar2. As can be seen from Figure 12, each locking member 85 is composed of a rod-shaped member having an axial direction along the rotation axis Ar2 parallel to the left-right direction d2.

FIG14 shows the locking member 85 and the rear wheel 42 in a state where the wheel locking device 80 is in the locked state S1. First, as components constituting the rear wheel 42, a tire 42b is retained on the outer periphery of the wheel portion 42a, and a brake plate 42c is fixed to the surface of the wheel portion 42a facing the locking member 85. The brake plate 42c has a plurality of receiving holes 42d formed therein, arranged around the rotation axis Ar2 of the rear wheel 42.

The receiving hole 42d is used to receive the front end of the locking member 85 of the wheel locking device 80 when the wheel locking device 80 is in the locked state S1. The receiving hole 42d is formed around the rotation axis Ar2 of the rear wheel 42.

However, as shown in Figures 12 and 14 , when the operating member 81 is switched to the locked position P1, the left and right locking members 85 are pushed outward in the left-right direction d2 via the connecting member 82 and retracted into the receiving hole 42d of the rear wheel 42. This restricts the rear wheel 42 from rotating about the rotation axis Ar2, resulting in the wheel locking device 80 being in the locked state S1. On the other hand, as shown in Figure 11 , when the operating member 81 is switched to the released position P2, the left and right locking members 85 are pulled inward in the left-right direction d2 via the connecting member 82 and withdrawn from the receiving hole 42d of the rear wheel 42. This releases the rotation restriction on the rear wheel 42, resulting in the wheel locking device 80 being in the released state S2.

It should be noted that each of the connecting arms 82b and 82c is biased by a spring (not shown) to push the locking member 85 outward in the left-right direction d2. Therefore, when the operating member 81 is switched to the locked position P1, if the locking member 85 deviates from the receiving hole 42d of the rear wheel 42, the locking member 85 is pressed by the brake plate 42c and is ready to be retracted into the receiving hole 42d.

However, when the wheel locking device 80 is in a state where the rotation of the wheel 4 is restricted (locked state), if the drive source 5 attempts to drive the wheel 4, the wheel 4 is not driven due to being locked, resulting in an excessive load being applied to the drive source 5. Therefore, in this embodiment, as shown in FIG13 , a lock sensor 90 is provided to monitor the state of the wheel locking device 80 so that the driving force from the drive source 5 is not transmitted to the wheel 4 when the wheel 4 is locked.

As shown in Figure 13, lock sensor 90 is fixed to mounting frame 11d via other components. Lock sensor 90 comprises a sensor body 92 equipped with a sensing button 91. A detection piece 93, which is pressed against sensing button 91, is cantilevered by sensor body 92. Specifically, one end of detection piece 93 is fixed to sensor body 92, while the other end is free.

When the operating member 81 swings between the locked position P1 and the released position P2, the right connecting arm 82c moves in conjunction with this movement. This movement of the right connecting arm 82c pushes out the detection piece 93, which presses the sensing button 91. This allows the lock sensor 90 to detect the position of the operating member 81.

However, the lock sensor 90 is not particularly limited as long as it can detect the position of the operating member 81. Other examples include a type that detects the movement of the magnetic body pushed out by the connecting arm 82c as a change in the magnetic field, and a type that detects the movement of the movable body pushed out by the connecting arm 82c as a change in brightness.

The information detected by the lock sensor 90 is transmitted to the control device 7. The control device 7 controls the timing of driving the drive source 5 based on the information detected by the lock sensor 90. The control device 7 of this embodiment controls the transmission of driving force from the drive source 5 to the wheels 4 while the lock sensor 90 detects that the operating member 81 is in the locked position P1.

Next, the operation of this embodiment having the above-described configuration will be described.

In particular, as can be seen from FIG2 , the four strain gauges 61 constituting the detection element 6 are located above the handle 21 in the up-down direction d3, and the handle 21 is located further back and below the connection position c1. According to such a configuration, the strain gauge 61 functions as shown in the following FIG15 to FIG18 . FIG15 to FIG18 are diagrams for explaining the function of the strain gauge 61 when the handle 20 is operated. It should be noted that in the following description, when the inner square material 22d is divided into two parts using a plane parallel to the long side direction of the inner square material 22d, the part to be the upper side is set as the upper area A1, and the part to be the lower side is set as the lower area A2 (refer to FIG8 ).

As shown in Figure 15, when the operator grasps the handle 21 and pushes the stroller 1 forward in the forward-backward direction d1, the upper area A1 of the inner square member 22d extends and the lower area A2 contracts. The information that the upper area A1 extends and the lower area A2 contracts is measured by four strain gauges 61. The information measured by the strain gauges 61 is transmitted to the control device 7. Upon receiving this information, the control device 7 recognizes that the handle 21 is being pushed forward or pressed downward, and supplies a current corresponding to the value measured by the strain gauges 61 to the circuit of the DC motors 51b and 52b, which are connected in series with two drive elements 51 and 52. This causes the DC motors 51b and 52b to rotate, and the drive shafts 51a and 52a connected to the DC motors 51b and 52b rotate the rear wheels 42 in the forward direction. In this way, the drive shafts 51a and 52a assist the rotation of the rear wheels 42, thereby reducing the operator's burden in pushing the stroller 1 forward.

If there are steps on the road surface, the operator presses the handle 21 downward in the vertical direction d3 to lift the front wheel 41. As shown in Figure 16, when the operator presses the handle 21 downward, similar to the situation in Figure 15, the upper area A1 of the inner member 22d extends and the lower area A2 contracts. The information about the extension of the upper area A1 and the contraction of the lower area A2 is measured by four strain gauges 61 and transmitted to the control device 7. Upon receiving this information, the control device 7 recognizes that the handle 21 is being pushed forward or pressed downward and supplies a current corresponding to the value measured by the strain gauges 61 to the circuit connected in series with two DC motors 51b and 52b. This causes the DC motors 51b and 52b to rotate, and the drive shafts 51a and 52a connected to the DC motors 51b and 52b rotate the rear wheel 42 in the forward direction. In other words, pressing the handle 21 downward causes the rear wheel 42 to rotate in the same way as pushing it forward. As a result, even during the operation of climbing over a step, the baby carriage 1 can be propelled without excessive burden by receiving assistance from the driving force generated by the driving source 5 .

On the other hand, when pushing the stroller 1 downhill, as shown in Figure 17, the operator grasps the handle 21 and pulls the stroller 1 rearward in the forward-backward direction d1. In this case, contrary to the situation in Figures 15 and 16, the upper region A1 of the inner member 22d contracts, while the lower region A2 extends. Information about the contraction of the upper region A1 and the extension of the lower region A2 is measured by four strain gauges 61 and transmitted to the control device 7. Upon receiving this information, the control device 7 recognizes that the handle 21 is being pulled rearward and supplies a current corresponding to the value measured by the strain gauges 61 to the circuit connected in series with the two DC motors 51b and 52b, in the opposite direction to that in Figures 15 and 16. This causes the DC motors 51b and 52b to rotate, and the drive shafts 51a and 52a connected to the DC motors 51b and 52b rotate the rear wheels 42 in the rearward direction. In this way, the drive shafts 51a and 52a assist the rotation of the rear wheels 42, thereby reducing the operator's burden in pulling the stroller 1 rearward.

Next, as shown in Figure 18, when turning the baby stroller 1, a difference is created in the forces pushing the two handle portions 21a and 21b forward, thereby enabling the baby stroller 1 to turn. In the example shown in Figure 18, by making the force applied to the right handle portion 21b greater than the force applied to the left handle portion 21a, the baby stroller 1 can be turned left. Even if different forces are applied to the two handle portions 21a and 21b, as in the case of Figure 15, the upper area A1 of the inner square material 22d stretches and the lower area A2 shrinks. The information that the upper area A1 stretches and the lower area A2 shrinks is measured by four strain gauges 61 and transmitted to the control device 7. Upon receiving this information, the control device 7 recognizes that the handle 21 is being pushed forward or pressed downward, and supplies a current corresponding to the value measured by the strain gauges 61 to the circuit connected in series with the two DC motors 51b and 52b. In the series circuit shown in Figure 6, when the two DC motors 51b and 52b are constructed to be identical, the magnitude of the current flowing through the two DC motors 51b and 52b is also equal. Therefore, it can be considered that the driving force provided by the two DC motors 51b and 52b to the wheel 4 is also equal.

However, when the stroller 1 is turned left, the inner left wheel 4 experiences greater resistance from the ground surface than the outer right wheel 4, making it difficult for the DC motor 51b connected to the inner left wheel 4 to rotate. If the speed of the DC motor 51b connected to the inner left wheel 4 decreases, the back electromotive force generated by the DC motor 51b decreases, making it easier for a larger current to flow through the series circuit. As a result, the current flowing through the DC motor 52b connected to the outer right wheel 4 becomes relatively larger, providing a greater driving force to the outer right wheel 4. This makes it easier for the outer right wheel 4 to rotate, resulting in a smoother steering operation.

When the stroller 1's travel operation is complete, the stroller 1 is stopped and the operating member 81 is switched from the released position P2 shown in Figure 11 to the locked position P1 shown in Figure 12 . This action is then linked to the locking member 85 restricting the rotation of the rear wheel 42, resulting in the wheel locking device 80 switching from the released state S2 to the locked state S1. The information indicating that the operating member 81 has switched to the locked state P1 is detected by the locking sensor 90 and transmitted to the control device 7. Upon receiving this information, the control device 7 controls the vehicle so that driving force is not transmitted from the drive source 5 to the wheels 4 while the locking sensor 90 detects that the operating member 81 is in the locked position P1. In other words, while the wheel locking device 80 is in the locked state S1, driving force is not transmitted from the drive source 5 to the wheels 4. This prevents the drive source 5 from operating in a manner that would otherwise drive the wheels 4, even if the operator inadvertently applies a load to the handle 20.

As described above, the stroller 1 of this embodiment includes: a stroller body 2; a plurality of wheels 4 supported by the stroller body 2 and rotating (rotating) about respective rotation axes Ar1 and Ar2; a drive source 5 supported by the stroller body 2 and providing driving force to at least one of the plurality of wheels 4; a detection element 6 that detects information related to a travel operation input to the stroller body 2; a control device 7 that controls the drive source 5 based on the information detected by the detection element 6 and adjusts the driving force provided by the drive source 5 to the wheels 4; and a wheel locking device 80 provided on the stroller body 2 so as to be switchable between a locked state S1 and a released state S2. The locked state S1 is a state in which at least one of the plurality of wheels 4 is restricted from rotating about the rotation axis Ar2, and the released state S2 is a state in which the restricted rotation of the wheel 4 is released. While the wheel locking device 80 is in the locked state S1, the driving force from the drive source 5 is not transmitted to the wheel 4. According to this embodiment, the drive source 5 can be prevented from driving the wheel 4 while the rotation of the wheel 4 is restricted, thereby suppressing the application of an excessive load to the drive source 5. Furthermore, the driving force applied to the wheels 4 by the driving source 5 can be adjusted in conjunction with the running operation of the baby stroller 1 , so that the baby stroller 1 can be operated as desired.

Furthermore, according to this embodiment, the rear wheels 42 are the wheels receiving driving force from the drive source 5, while the front wheels 41 are supported on the stroller body 2 via the casters 3. The support of the front wheels 41 on the stroller body 2 via the casters 3 allows for smooth steering of the stroller 1. Furthermore, considering the rearward position of the handle 20 operated by the operator and the center of gravity of the infant riding in the stroller 1, it is expected that a load is easily applied to the rear wheels 42, and the rear wheels 42 maintain stable contact with the ground. By providing driving force from the drive source 5 to the stably grounded rear wheels 42, stable drive assistance by the drive source 5 can be achieved.

Furthermore, according to this embodiment, the drive source 5 includes a first drive element 51 for providing a driving force to at least one of the plurality of wheels 4, and a second drive element 52 for providing a driving force to a wheel 4 among the plurality of wheels 4 different from the wheel 4 provided with a driving force by the first drive element 51, and provided separately from the first drive element 51. According to this aspect, by providing different driving forces to different wheels 4, it is possible to achieve an appropriate distribution of driving force according to the running state of the stroller 1.

Furthermore, according to this embodiment, the wheel 4 driven by the first drive element 51 and the wheel 4 driven by the second drive element 52 are positioned differently in the left-right direction d2. The first drive element 51 and the second drive element 52 each include a DC motor. The DC motor 51b of the first drive element 51 and the DC motor 52b of the second drive element 52 are connected in series with respect to the power source 75. When the stroller 1 is turned, the inner wheel 4 experiences greater resistance from the ground surface than the outer wheel 4. Therefore, when the DC motors 51b and 52b of the two drive elements 51 and 52 are connected in series, the DC motor 51b connected to the inner wheel 4 becomes less likely to rotate. If the rotational speed of the DC motor 51b connected to the inner wheel 4 decreases, the back electromotive force generated by the DC motor 51b decreases, making it easier for a larger current to flow through the series circuit. As a result, the current flowing through the DC motor 52b connected to the outer wheel 4 increases relatively, enabling a greater driving force to be provided to the outer wheel 4. Based on the above, when the DC motors 51b and 52b of the two drive elements 51 and 52 are connected in series, the wheel 4 serving as the outer wheel can be easily rotated during the steering operation, and the steering operation can be performed smoothly.

Furthermore, according to this embodiment, the stroller body 2 includes a frame body 10 that supports a plurality of wheels 4, and a handle 20 connected to the frame body 10. The detection element 6 is provided on the handle 20 and detects information related to the load applied to the handle 20. By selecting information related to the load applied to the handle 20 as information related to the travel operation input to the stroller body 2, it is possible to provide driving force from the drive source 5 to the wheels 4 in accordance with the operator's intention related to the travel operation.

Furthermore, according to this embodiment, the handle 20 includes a grip 21 for the operator's hand and a handle body 22 connecting the handle 21 to the stroller body 2. When the detection element 6 detects that the handle 21 is being pushed forward or pressed downward, the control device 7 causes the drive source 5 to provide driving force to move the wheels 4 forward. When the detection element 6 detects that the handle 21 is being pulled rearward, the control device 7 causes the drive source 5 to provide driving force to move the wheels 4 backward. This configuration allows the driving force generated by the drive source 5 on the wheels 4 to be adjusted in coordination with the operator's operation of the handle 21. In particular, according to this embodiment, even when the handle 21 is pressed downward to raise the front wheels 41 in order to overcome a step on the ground, the drive source 5 still drives the wheels 4 forward. Therefore, even when overcoming a step, the stroller 1 can be propelled forward without excessive burden, supported by the driving force generated by the drive source 5.

Furthermore, according to this embodiment, the detection element 6 includes a plurality of strain gauges 61 mounted on the handle body 22 of the handle 20. At least one strain gauge 61 extends when the handle 21 is pushed forward or pressed downward, and shortens when the handle 21 is pulled rearward, or shortens when the handle 21 is pushed forward or pressed downward, and extends when the handle 21 is pulled rearward. According to this configuration, the detection element 6 is implemented using the strain gauges 61, thereby avoiding a complex structure and stably detecting information regarding the operator's operation of the handle 21. In order to further stably detect information regarding the operator's operation of the handle 21, the handle 21 may be located further rearward and lower than the connection position c1 between the handle body 22 and the frame body 10, or further forward and higher.

In particular, according to this embodiment, the handle 21 is located further rearward and downward than the connection position c1, and the strain gauge 61 is attached to the portion of the handle body 22 between the connection position with the operating member 21 and the connection position c1. In this case, the portion of the handle body 22 to which the strain gauge 61 is attached expands and contracts with high sensitivity in conjunction with the load applied to the handle 21 by the operator. Therefore, the strain gauge 61 can detect information indicating the operator's operation of the handle 21 with even greater precision.

Furthermore, according to this embodiment, the wheel locking device 80 includes an operating member 81 movable between a locked position P1 and a released position P2; and a locking member 85 connected to and operating in conjunction with the operating member 81. While the operating member 81 is in the locked position P1, the locking member 85 engages with the wheel 4, restricting rotation of the wheel 4 about the rotation axis Ar2. While the operating member 81 is in the released position P2, the locking member 85 moves away from the wheel 4, releasing the rotation restriction of the wheel 4. With this configuration, the wheel locking device 80 can easily switch between a locked state S1, which restricts rotation of the wheel 4, and a released state S2, which releases the rotation restriction, simply by switching the operating member 81 between the locked position P1 and the released position P2. In other words, the wheel locking device 80 is superior in that it can easily switch between the locked state S1 and the released state S2.

Furthermore, according to this embodiment, a lock sensor 90 is further provided for detecting the state of the wheel locking device 80. While the lock sensor 90 detects that the wheel locking device 80 is in the locked state S1, the control device 7 controls the wheel 4 so that the driving force from the drive source 5 is not transmitted. In other words, the wheel locking device 80 further includes a lock sensor 90 for detecting the position of the operating member 81. While the lock sensor 90 detects that the operating member 81 is in the locked position P1, the control device 7 controls the wheel 4 so that the driving force from the drive source 5 is not transmitted. According to this embodiment, by detecting the state of the wheel locking device 80 using the lock sensor 90, the control device 7 controls the wheel 4 so that the driving force from the drive source 5 is not transmitted to the wheel 4 even when the rotation of the wheel 4 is restricted. Therefore, a stroller 1 can be more reliably implemented that can prevent the drive source 5 from driving the wheel 4 even when the rotation of the wheel 4 is restricted.

Furthermore, according to this embodiment, the wheel locking device 80, in the locked state S1, restricts at least the wheel 4, which is capable of receiving driving force from the drive source 5, from rotating about the rotation axis Ar2. In this case, since the wheel 4 locked by the wheel locking device 80 is the same wheel 4 as the wheel 4 receiving driving force from the drive source 5, if the drive source 5 drives the wheel 4 while the wheel 4 is locked, an excessive load is further applied to the drive source 5. Therefore, in this stroller 1, the effect of preventing the drive source 5 from driving the wheel 4 while the wheel 4's rotation is restricted is more pronounced.

It should be noted that various modifications can be made to the above-described embodiment. An example of a modification will be described below.

For example, in the above embodiment, two seat units 8a and 8b are arranged side by side. However, the number of seat units 8a and 8b is not limited to this example. For example, a single seat unit may be provided, or two or more seat units may be provided and arranged in a front-to-back manner.

Furthermore, in the above embodiment, the DC motors 51b and 52b of the two drive elements 51 and 52 are connected in series with respect to the power supply 75. However, the circuit design associated with the DC motors 51b and 52b is not limited to the above example. The DC motors 51b and 52b of the two drive elements 51 and 52 may also be connected in parallel with respect to the power supply 75.

Furthermore, in the above embodiment, the detection element 6 is shown as an example comprising a strain gauge 61. However, the form of the detection element 6 is not limited to the above example. The detection element 6 may be any type as long as it can detect information related to the travel operation input to the stroller body 2. Other examples include a torque sensor, a pressure sensor, a magnetostrictive sensor, etc., attached to the handle body 22. For example, a pressure sensor may be a type that captures the load applied to the handle 20 as a change in the pressure of the working fluid, measures this pressure change using a pressure-sensitive element via a diaphragm, and outputs it as an electrical signal.

In the above embodiment, the column 22a, which is composed of a single support column, connects the rear upper frame 12d and the handle 21. However, the shape of the column 22a is not limited to the above example. The column 22a may be composed of a plurality of support columns and connect the rear upper frame 12d and the handle 21.

In the above embodiment, as shown in FIG5 , an example is shown in which two drive elements 51 and 52 drive the left and right rear wheels 42. However, the configuration of the drive wheels 4 is not limited to the above example. FIG19 shows another example of the drive wheels 4. In the example shown in FIG19 , three rear wheels 42 are supported by the base frame 11, and the drive source 5 is connected to the center rear wheel 42 between the left and right rear wheels 42.

FIG20 illustrates the configuration of the wheel locking device 80. As shown in FIG20 , an operating member 81 constituting the wheel locking device 80 is supported by the base frame 11 near the center rear wheel 42. The operating member 81 shown in FIG20 is configured as a foot-operated pedal and is capable of swinging between a release position P2 shown in FIG20 and a lock position P1 (see FIG20 ) that is depressed to a position lower than the release position P2.

Connected to the operating member 81 are a lock member 85 that restricts the rotation of the center rear wheel 42 , another lock member 85 that restricts the rotation of the left rear wheel 42 , and another lock member 85 that restricts the rotation of the right rear wheel 42 .

The locking member 85 that restricts the rotation of the center rear wheel 42 is integrally formed with the operating member 81 and operates integrally with the operating member 81. The center locking member 85 includes a locking protrusion 85a, which is received in a locking groove 42e (see FIG. 21 ) of a brake plate 42c included in the center rear wheel 42.

The locking member 85 that restricts the rotation of the left and right rear wheels 42 is connected to the operating member 81 via the connecting member 82. The connecting member 82 is composed of flexible left and right wires 82d and 82e, and extends or pushes the left and right locking members 85 in conjunction with the operation of the operating member 81.

FIG21 shows an enlarged view of the left locking member 85. It should be noted that, although not shown, the right locking member 85 is constructed substantially the same as the left locking member 85 shown in FIG21. As shown in FIG21, the left locking member 85 is supported by the base frame 11 so as to be slidable in the vertical direction d3. The end of the wire 82d is connected to the locking member 85 so that it can operate in conjunction with the operation of the operating member 81.

The lock member 85 is provided with a lock pin 85b having a longitudinal axis along the rotation axis Ar2 of the rear wheel 42. The lock pin 85b is received in a receiving hole 42d (see FIG. 14 ) formed in the brake plate 42c of the left rear wheel 42.

Furthermore, a lock sensor 90 is supported on the base frame 11 to detect slippage of the lock member 85. The lock sensor 90 includes a sensor body 92 provided with a sensing button 91, and a sensing piece 93 that presses the sensing button 91 is cantilevered by the sensor body 92.

Figure 22 shows the rear wheel 42 locked using the left locking member 85. As shown in Figure 22, when the operating member 81 is switched to the locked position P1, the three locking members 85 swing in conjunction with the operating member 81, and the locking protrusion 85a or locking pin 85b of each locking member 85 is received in the corresponding locking groove 42e or receiving hole 42d of the rear wheel 42. This switches the wheel locking device 80 to the locked state S1. The lock sensor 90 detects the switch to the locked state S1 and transmits it to the control device 7.

On the other hand, when the operating member 81 is switched to the released position P2 shown in Figures 20 and 21, the three locking members 85 swing in conjunction with the operating member 81, and the locking protrusion 85a or the locking pin 85b moves out of the locking groove 42e or the receiving hole 42d of the rear wheel 42. Thus, the wheel locking device 80 is switched to the released state S2. The information that the wheel locking device 80 has switched to the released state S2 is detected by the lock sensor 90 and transmitted to the control device 7.

According to the embodiment shown in Figures 19 to 22, the wheel locking device 80 includes an operating member 81 movable between a locked position P1 and a released position P2; and a locking member 85 connected to and operating in conjunction with the operating member 81. When the operating member 81 is in the locked position P1, the locking member 85 engages with the wheel 4 to restrict rotation of the wheel 4 about the rotation axis Ar2. When the operating member 81 is in the released position P2, the locking member 85 moves away from the wheel 4 to release the restricted rotation of the wheel 4. According to this embodiment, simply by switching the operating member 81 between the locked position P1 and the released position P2, the wheel locking device 80 can easily switch between the locked state S1, which restricts the rotation of the wheel 4, and the released state S2, which releases the restricted rotation of the wheel 4. In other words, the wheel locking device 80 is superior in that it can easily switch between the locked state S1 and the released state S2.

It should be noted that several modified examples with respect to the above-mentioned embodiment have been described above, but it is obvious that a plurality of modified examples may be appropriately combined and applied.

Claims (5)

1. A baby stroller, characterized by comprising: Baby stroller body; a plurality of wheels supported by the stroller body and rotatable about respective rotation axes; a driving source supported by the stroller body and providing driving force to at least one of the plurality of wheels; a detection element for detecting information related to a moving operation input into the stroller body; a control device for controlling the drive source based on information detected by the detection element to adjust the drive force provided from the drive source to the wheels; The wheel locking device is provided on the stroller body in a manner capable of switching between a locked state and a released state, wherein the locked state is a state in which rotation of at least one of the plurality of wheels about its own rotation axis is stopped, and the released state is a state in which the state in which the rotation of the wheel is restricted is released. wherein, while the wheel locking device is in the locked state, the driving force from the driving source is not transmitted to the wheel; The wheel locking device comprises: an operating member movable between a locking position and a releasing position; and a locking member connected to the operating member and operating in conjunction with the operating member. The locking member is in a locked state in which the wheel is engaged with the locking member to stop the wheel from rotating about its own rotation axis while the operating member is in the locking position, and is in a released state in which the wheel is released by being separated from the wheel while the operating member is in the releasing position. The operating member moves in a horizontal direction, and the horizontal movement of the operating member causes the horizontal movement of the wheel locking device. The stroller further includes: a lock sensor for detecting a state of the wheel locking device, and the control device controls the stroller so that the driving force from the drive source is not transmitted to the wheel while the lock sensor detects that the wheel locking device is in the locked state. Alternatively, the stroller further includes: a lock sensor for detecting a position of the operating member, and the control device controls the stroller so that the driving force from the drive source is not transmitted to the wheel while the lock sensor detects that the operating member is in the locked position. 2. The baby stroller according to claim 1, wherein: The wheel locking device stops at least the rotation of the wheel, to which the driving force is supplied by the driving source, about its own rotation axis in the locked state. 3. The baby stroller according to claim 1 or 2, characterized in that: The wheel provided with driving force by the driving source among the plurality of wheels is a rear wheel, The front wheel among the plurality of wheels is supported on the stroller body via casters. 4. The baby stroller according to claim 1 or 2, characterized in that: The baby carriage body comprises: a frame body supporting the plurality of wheels; and a handle connected to the frame body. The detection element is provided on the handle and detects information related to a load applied to the handle. 5. The baby stroller according to claim 3, wherein: The baby carriage body comprises: a frame body supporting the plurality of wheels; and a handle connected to the frame body. The detection element is provided on the handle and detects information related to a load applied to the handle.