JP2004090757A - Foldable barrow - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an easily and rapidly foldable and expansible barrow. <P>SOLUTION: This barrow comprises a front wheel frame member 1, a rear wheel frame member 2, a front lower link member 10, and a rear lower link member 11, the members forming a quadric crank chain mechanism. A tension spring 15 is provided between the link members 10 and 11. The barrow having the quadric crank chain mechanism is automatically folded by the force of the spring 15. The lower end of a working link member 17 is pivotally fixed to the link member 11. The inner end of a lever member 23 is pivotally fixed to a vertical frame member 6 that is the upward extension part of the frame member 1. The middle part of the lever member 23 is pivotally fixed to the upper end of the link member 17. When the lever member 23 is pivotally moved upward, a hook member 27 and a locking pin 26 are laid in an engagingly locked state. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a foldable wheelbarrow. Wheelbarrows include prams, nursing wheelchairs, and silver cars (four-wheeled vehicles with weak legs that are mainly used as walking aids by seniors when shopping or taking a walk). Is included.
[0002]
[Prior art]
It is convenient to fold such a wheelbarrow compactly so as to take up less space when not in use. The same applies to loading on a car or getting on a train, and it is convenient to be able to fold and unfold easily and quickly. In particular, in the case of a silver car, since it is used by elderly people whose athletic ability is declining, it is desired that folding and unfolding can be quickly performed by simple operation without applying force. However, a wheelbarrow satisfying such demands has not been realized yet.
[0003]
[Problems to be solved by the invention]
Therefore, an object of the present invention is to provide a handcart that can be quickly folded and unfolded by a simple operation without applying force.
[0004]
[Means for Solving the Problems]
To solve the above problems, according to the present invention,
A pair of left and right front wheel frame members and a pair of left and right rear wheel frame members are provided with wheels at their lower ends, and the upper ends of the front wheel frame members and the rear wheel portion frame members on the left and right sides are pivotally connected to each other. A front wheel frame member and a rear wheel frame member being connected,
A pair of front and rear connection frame members for connecting between the pair of left and right front wheel frame members and between the pair of left and right rear wheel frame members,
A pair of right and left upright frame members formed as an upper extension of the front wheel frame member or the rear wheel frame member,
A pair of left and right front lower link members and a pair of left and right rear lower link members, the outer ends of the front lower link member and the rear lower link member on the left and right sides are the front wheel frame member and the rear wheel A front lower link member and a rear lower link member each pivotally connected to the frame member and inner ends thereof are pivotally connected to each other;
A pair of left and right tension coil springs are provided between the front lower link member and the rear lower link member, and the front wheel frame member, the rear wheel frame member, the front lower link member, and the rear A coil spring acting to fold back and forth each of a pair of left and right four-bar rotary chain mechanisms formed from the lower link member,
A pair of left and right actuation link members, the lower end of which is pivotally connected to one of the front lower link member and the rear lower link member and extends upward,
A handle frame member having a pair of right and left upright portions formed as an upper extension of the actuation link member,
An upper link member having a pair of left and right upper link members, wherein a front end is pivotally connected to the front wheel frame member or the rear wheel frame member or the upright frame member, and a rear end is pivotally connected to an upper end of the operation link member. A link member,
A lever member having a pair of left and right side portions formed as a rear extension of the upper link member and a horizontal portion connecting the rear ends of the pair of side portions; A lever member, wherein the member and the upper link member are moved, whereby each of the pair of left and right four-bar rotating chains is deployed back and forth against the force of the coil spring;
A pair of left and right locking pins provided on the pair of left and right upright portions of the pair of left and right operating link members or the handle frame member,
A hook member attached to the pair of right and left upright frame members, which can pivot between a locking position and an unlocking position, and interlock with the locking pin when in the locking position. A pair of left and right hook members,
Biasing means for biasing the hook member to the locking position;
With
The hook member has a cam surface, and the cam surface approaches the locking pin when the four-bar rotating chain mechanism is deployed back and forth against the force of the coil spring. Engagement with the locking pin to automatically guide the hook member to the locking position to interlock with the locking pin.
A collapsible wheelbarrow is provided.
[0005]
The wheelbarrow is a bar member provided between the pair of left and right hook members and extending horizontally, and is operated to move the pair of left and right hook members from the locking position against the force of the urging means. It may further comprise a bar member adapted to be able to pivot synchronously to the unlocked position.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a side view of one embodiment of a foldable wheelbarrow according to the present invention, wherein the wheelbarrow is locked in a deployed state. FIG. 2 is a perspective view showing the state in which the lock by the hook member is released and the wheelbarrow transitions from the unfolded state to the folded state, and FIG. 3 is an enlarged perspective view showing the unlocked hook member and its peripheral mechanism. FIG. 4 is a side view showing the wheelbarrow in a folded state. The illustrated wheelbarrow embodiment of the present invention is a silver car. In order to explain the mechanism easily, members other than the framework, such as a seat surface, a storage portion, and a backrest portion, are omitted.
[0007]
The handcart includes a pair of left and right front wheel frame members 1 and a pair of left and right rear wheel frame members 2. Wheels W are provided at lower ends of the front wheel frame member 1 and the rear wheel frame member 2, respectively. On each of the left and right sides, the upper ends of the front wheel frame member 1 and the rear wheel portion frame member 2 are pivotally connected to each other by pins 3.
[0008]
The pair of left and right front wheel frame members 1 and the pair of left and right rear wheel frame members 2 are connected by a pair of front and rear connection frame members 4 and 5 (see FIG. 2).
[0009]
An upright frame member 6 is provided above the upper ends of the front wheel frame member 1 and the rear wheel frame member 2 connected by the pins 3. In the illustrated embodiment, the upright frame member 6 is integrally formed as an upper extension of the front wheel frame member 1. However, the upright frame member 6 may be integrally formed as an upper extension of the rear wheel frame member 2, or alternatively, may be fixed to the upper end of the front wheel frame member 1 or the rear wheel frame member 2, These upward extensions may be used. The upper ends of the pair of right and left upright frame members 6 may be connected by a horizontal member to form an inverted U-shaped frame.
[0010]
Between the pair of left and right front wheel frame members 1, a U-shaped seat frame member 7 with a closed front is pivotally connected by pins 8. The forward pivoting of the seat frame member 7 is stopped by the stopper 9 attached to the seat frame member 7 abutting on the front wheel frame member 1. The seat frame member 7 is a member for attaching a seat surface when a silver car user sits down during a break. Further, by pivoting the seat frame member 7 rearward together with the seat surface, shopping luggage and the like can be accommodated in a space below the seat surface. In addition, the pair of right and left upright frame members 6 is a member for attaching a cloth for a backrest when a silver car user sits on a seat surface.
[0011]
On each of the left and right sides, a front lower link member 10 and a rear lower link member 11 are provided between the front wheel frame member 1 and the rear wheel frame member 2. The outer ends of the front lower link member 10 and the rear lower link member 11 are pivotally connected to the front wheel frame member 1 and the rear wheel frame member 2 by pins 12 and 13, respectively. The inner ends are pivotally connected to each other by pins 14.
[0012]
On each of the left and right sides, a tension coil spring 15 is provided between the front lower link member 10 and the rear lower link member 11. The spring 15 exerts a force to fold the wheelbarrow. In other words, a pair of left and right four-bar rotary chain mechanisms are formed from the front wheel frame member 1, the rear wheel frame member 2, the front lower link member 10, and the rear lower link member 11, and the tension coil spring 15 And a force acting to fold each of the four-joint rotary chain mechanisms back and forth.
[0013]
On each of the left and right sides, a lower end is pivotally connected to an intermediate portion of the rear lower link member 11 by a pin 16 and an operating link member 17 extending upward is provided. Although the operating link member 17 is straight in the illustrated embodiment, the lower end portion may be bent forward and the lower end may be pivotally connected to the front lower link member 10.
[0014]
The actuating link member 17 extends upward, and the upward extension forms an upright portion of the handle frame member 18. The upright portion of the handle frame member 18 may be configured such that the inner tube and the outer tube are nested and combined, and the height of the handle may be adjusted by changing the relative positions thereof. The upper ends of the pair of left and right upright portions of the handle frame member 18 may be connected by a horizontal member so that the user can easily grip the handle.
[0015]
An upper link member 19 is provided on each of the left and right sides. The front end of the upper link member 19 is pivotally connected to the tab 21 of the upright frame member 6 by a pin 20. The rear end of the upper link member 19 is pivotally connected to the upper end of the operating link member 17 by a pin 22. By a design change, the front end of the operating link member 17 may be pivotally connected to an upper portion of the front wheel frame member 1 or the rear wheel frame member 2.
[0016]
A lever member 23 is provided on an extension of the upper link member 19. The lever member 23 has a U-shape including a pair of left and right side portions 24 formed as a rear extension of the upper link member 19 and a horizontal portion 25 connecting between the rear ends of the pair of side portions 24. are doing.
[0017]
A locking pin 26 and a hook member 27 are provided on each of the left and right sides to hold the handcart in the deployed state as shown in FIG. The locking pin 26 is provided on a tab 28 attached to the operating link member 17 in the illustrated embodiment. For design reasons, a tab on which the locking pin 26 is provided may be attached to the upright portion of the handle frame member 18.
[0018]
The hook member 27 is pivotally attached to the upright frame member 6 by a pin 29. The hook member 27 is pivotable between a lower locking position and an upper unlocking position, and is interlockable with the locking pin 26 when in the locking position.
[0019]
A tension coil spring 30 is provided as urging means for urging the hook member 27 to the locking position.
The hook member 27 has a cam surface 31. This cam surface 31 approaches the locking pin 26 and engages with the locking pin 26 when the handcart is moved from the folded state shown in FIG. After being once pivoted upward against the urging force of the spring 30, it is pivoted downward by the urging force of the spring 30 and automatically guided to the locking position. The hook member 27 at the locking position has the locking pin 26 inserted into the groove 32 to be in the mutual locking state.
[0020]
As shown in FIG. 2, it is convenient to provide a bar member 33 extending horizontally between the pair of left and right hook members 27. This is because, by grasping and moving the bar member 33 up and down, the pivoting of the left and right hook members 27 can be easily performed in synchronization.
[0021]
A method for unfolding and folding the wheelbarrow according to the present invention will be described. The lever member 23 of the wheelbarrow in the folded state as shown in FIG. 4 is held with one hand and pivoted upward as indicated by arrow A. At this time, the opposite hand may be attached to the upright frame member 6 or the horizontal member extending between the upper ends of the upright frame members 6. By the upward pivoting of the lever member 23, the operating link member 17 is lifted, and the rear lower link member 11 pivots clockwise about the pin 13 in the figure. At this time, the upper link member 19 integrated with the lever member 23 also acts to push the position of the pin 3 forward. In this manner, the pair of left and right four-bar rotational chain mechanisms including the front wheel frame member 1, the rear wheel frame member 2, the front lower link member 10, and the rear lower link member 11 provide the force of the tension coil spring 15 Deploy back and forth in opposition.
[0022]
The wheelbarrow of FIG. 2 is not yet fully deployed. When the lever member 18 is further pivoted upward from the state of FIG. 2, the locking pin 26 and the hook member 27 approach each other. Thereafter, as described above, the engagement between the cam surface 31 of the hook member 27 and the locking pin 26 starts, and the hook member 27 pivots upward against the urging force of the spring 30 and then pivots downward. The locking pin 26 is locked in the groove 32 of the hook member 27. FIG. 1 shows the wheelbarrow fully deployed in this manner.
[0023]
To fold the pushcart, the bar member 33 (FIG. 2) extending between the hook members 26 is grasped and pivoted upward. Then, the locking pin 26 comes off from the inside of the groove 32 of the hook member 27. When there is no bar member 33, the left and right hook members 27 are simultaneously pivoted upward with both hands. When the locked state between the hook member 27 and the locking pin 26 is released, the left and right formed by the front wheel frame member 1, the rear wheel frame member 2, the front lower link member 10, and the rear lower link member 11 The pair of four-bar linkage chains are folded in the front-rear direction by the force of the tension coil spring 15.
[0024]
【The invention's effect】
The wheelbarrow of the present invention can be quickly folded and unfolded by a simple operation without applying force by the action of the coil spring and the lever member.
[0025]
By employing the bar member provided between the pair of left and right hook members, it becomes easier to release the lock in the deployed state of the handcart.
[Brief description of the drawings]
FIG. 1 is a side view of one embodiment of a foldable wheelbarrow according to the present invention, the wheelbarrow being locked in a deployed state.
FIG. 2 is a perspective view of a state in which the lock by the hook member is released and the handcart in FIG.
FIG. 3 is an enlarged perspective view showing the hook member unlocked and its peripheral mechanism.
FIG. 4 is a side view showing the wheelbarrow in a folded state.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Front wheel frame member, 2 Rear wheel frame member, 3 pins, 4,5 connection frame member, 6 Upright frame member, 7 Seat frame member, 8 pins, 9 Stopper, 10 Front lower link member, 11 Rear Lower link member, 12, 13, 14 pin, 15 tension coil spring, 16 pin, 17 link member for operation, 18 handle frame member, 19 upper link member, 20 pin, 21 tab, 22 pin, 23 lever member, 24 side Part, 25 horizontal part, 26 locking pin, 27 hook member, 28 tab, 29 pin, 30 tension coil spring, 31 cam surface, 32 groove, 33 bar member, W wheel.

Claims (2)

A pair of left and right front wheel frame members and a pair of left and right rear wheel frame members are provided with wheels at their lower ends, and the upper ends of the front wheel frame members and the rear wheel portion frame members on the left and right sides are pivotally connected to each other. A front wheel frame member and a rear wheel frame member being connected,
A pair of front and rear connection frame members for connecting between the pair of left and right front wheel frame members and between the pair of left and right rear wheel frame members,
A pair of right and left upright frame members formed as an upper extension of the front wheel frame member or the rear wheel frame member,
A pair of left and right front lower link members and a pair of left and right rear lower link members, the outer ends of the front lower link member and the rear lower link member on the left and right sides are the front wheel frame member and the rear wheel A front lower link member and a rear lower link member each pivotally connected to the frame member and inner ends thereof are pivotally connected to each other;
A pair of left and right tension coil springs are provided between the front lower link member and the rear lower link member, and the front wheel frame member, the rear wheel frame member, the front lower link member, and the rear A coil spring acting to fold back and forth each of a pair of left and right four-bar rotary chain mechanisms formed from the lower link member,
A pair of left and right actuation link members, the lower end of which is pivotally connected to one of the front lower link member and the rear lower link member and extends upward,
A handle frame member having a pair of right and left upright portions formed as an upper extension of the actuation link member,
An upper link member having a pair of left and right upper link members, wherein a front end is pivotally connected to the front wheel frame member or the rear wheel frame member or the upright frame member, and a rear end is pivotally connected to an upper end of the operation link member. A link member,
A lever member having a pair of left and right side portions formed as a rear extension of the upper link member and a horizontal portion connecting the rear ends of the pair of side portions; A lever member, wherein the member and the upper link member are moved, whereby each of the pair of left and right four-bar rotating chains is deployed back and forth against the force of the coil spring;
A pair of left and right locking pins provided on the pair of left and right upright portions of the pair of left and right operating link members or the handle frame member,
A hook member attached to the pair of right and left upright frame members, which can pivot between a locking position and an unlocking position, and interlock with the locking pin when in the locking position. A pair of left and right hook members,
Biasing means for biasing the hook member to the locking position;
With
The hook member has a cam surface, and the cam surface approaches the locking pin when the four-bar rotating chain mechanism is deployed back and forth against the force of the coil spring. Engagement with the locking pin to automatically guide the hook member to the locking position to interlock with the locking pin.
Collapsible wheelbarrow. By operating a bar member provided between the pair of left and right hook members and extending horizontally, the pair of left and right hook members is operated from the locked position to the unlocked position against the force of the urging means. 2. The collapsible wheelbarrow of claim 1, further comprising a bar member adapted to be pivotally synchronized with the wheel.

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