Wheelbarrow locking device

Abstract

To provide a handcart lock device that can extremely easily perform a release operation of a lock portion when releasing braking of a brake lever.SOLUTION: A brake lever 18 is provided at a spaced position spaced below a handle portion 11 of a handcart 1A, and is operated toward an upper braking position close to the handle portion 11 when braking right and left rear wheels 15R. A lock portion 41 biased by a coil spring 42 is rotatably provided at the center of the handle portion 11 in a right-left direction, and a hook portion 45 configured to lock the brake lever 18 at the braking position is provided. When the brake lever 18 is operated further upward from the braking position to the closest position, the lock at the braking position by the hook portion 45 is released, and the lock portion 41 is automatically moved from the locked position to the unlocked position by the biasing force of the coil spring 42, and the brake lever 18 is returned to the spaced position.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a locking device for a handcart such as a silver cart.

Background Art

[0002] Generally, a handcart includes left and right steering frames extending downward from a steering portion that a user grips with both hands, and left and right leg frames connected to lower ends of the both steering frames and supporting front and rear wheels so as to be rotatable freely.

[0003] Some handcarts also include a braking lever provided at a separation position separated from the steering portion. By operating this braking lever toward a braking position approaching the steering portion, the left and right rear wheels among the front and rear wheels are braked (see Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, in the conventional device, when holding the handcart in a braked state, it is necessary to provide a locking mechanism for locking the braking lever at the braking position. As such a locking mechanism, a locking portion for detachably locking the braking lever at the braking position is provided on the steering portion, and the braking lever operated to the braking position is locked by the locking portion, so as to hold the left and right rear wheels in a braked state.

[0006] In that case, when releasing the braking of the braking lever, it is necessary to perform a release operation each time from a locking position where the locking portion locks the braking lever at the braking position to a locking release position where the braking of the braking lever is released, and the release operation of the locking portion is very troublesome.

[0007] The present invention has been made in view of the above, and its objective is to provide a locking device for a handcart that makes it very easy to release the locking part when releasing the brake lever. [Means for solving the problem]

[0008] To achieve the above objective, the present invention is based on a handcart that includes left and right steering frames extending downward from a steering section that the user grasps with both hands, and left and right leg frames connected to the lower ends of both steering frames, which support the front and rear wheels so that they can roll freely. Furthermore, a braking lever is provided at a distance from the steering section, which is operated toward a braking position that approaches the steering section in order to brake the left and right rear wheels of the front and rear wheels, and a locking mechanism is provided on the steering section that locks the braking lever in the braking position so that the left and right rear wheels cannot roll. In addition, the braking lever is set to be operable from the braking position to a closest position that is even closer to the steering section. On the other hand, the locking mechanism is provided with a locking portion that locks the brake lever to the brake position so that it can be locked and unlocked, and a biasing means that biases the locking portion from the locking position that locks the brake lever to the unlocked position in which the brake is released. ru.

[0009] Furthermore, the braking lever is supported below the steering unit so as to be slidable vertically along each steering frame, and is operated from a position separated from the steering unit so as to be moved closer to the steering unit from below, and is set to be operated from this braking position to a position closer to the steering unit from even further below. The locking part is supported so as to be rotatable around the axis of the steering unit and has a hook part that locks the braking lever in a way that it embraces the braking lever from below so as to restrict its movement to the separated position below at the braking position, and is characterized in that when the braking lever is operated from the braking position to the closest position a vertical space is created between the braking lever at the braking position and the hook part that was embracing it from below, the locking part automatically moves from the locking position to the unlocked position by the biasing force of the biasing means, and the braking lever returns to the separated position.

[0010] In response to this, To achieve the above objective, the present invention similarly assumes a handcart equipped with left and right steering frames extending downward from a steering section that the user grasps with both hands, and left and right leg frames connected to the lower ends of both steering frames, which support the front and rear wheels so that they can roll freely. Furthermore, a braking lever is provided at a distanced position from the steering section, which is operated toward a braking position that approaches the steering section in order to brake the left and right rear wheels of the front and rear wheels, and a locking mechanism is provided on the steering section that locks the braking lever in the braking position so that the left and right rear wheels cannot roll. In addition, the braking lever is set to be operable from the braking position to a closest position that is even closer to the steering section. On the other hand, the locking mechanism is similarly provided with a locking portion that locks the brake lever to the brake position so as to be able to lock and unlock it, and a biasing means that biases the locking portion from the locking position, which locks the brake lever to the brake position, toward the unlocked position, which releases the brake of the brake lever. Furthermore, the braking lever is rotatably supported around a horizontal axis extending in the left-right direction at the midpoint of the vertical direction of each steering frame, and is operated from a distanced position, which is further forward from the steering unit, to a braking position, which is closer to the steering unit from the front, and from this braking position to a closest position, which is even closer to the steering unit from the front. The locking part is rotatably supported around the axis of the steering unit and has a hook part that locks the braking lever in a way that it embraces the braking lever from the front so that it restricts the movement of the braking lever to the distanced position forward at the braking position, and is characterized in that when the braking lever is operated from the braking position to the closest position, a space is created in the front-rear direction between the braking lever at the braking position and the hook part that was embracing it from the front, causing the locking part to automatically move from the locking position to the unlocked position by the biasing force of the biasing means, and the braking lever to return to the distanced position.

[0011] Furthermore, as the biasing means, a coil spring is applied, with one end fixed to the steering part and the other end fixed to the locking part, while being wound around a part of the perimeter of the steering part. The coil spring may be configured to extend when the braking lever is locked in the braking position by the hook part, and to contract when the locking in the braking position by the hook part is released, thereby applying a biasing force to the locking part.

[0012] Furthermore, a slider is connected to the brake lever, which moves linearly up and down from the distanced position to the closest position of the brake lever, and the slider is provided with a sliding body that slides up and down inside it. In addition, brake pads that press against the left and right rear wheels when the brake lever is in the braking position are connected to the sliding body via a wire, so that when the brake lever is operated toward the braking position the slider also moves toward the steering part, and when the brake lever is separated from the distanced position the slider also moves toward the steering part. The lower end of the sliding body may be connected to the wire, and when the brake lever is operated toward the braking position the wire may be brought into contact with the bottom of the slider via an expandable and contractible elastic body. [Effects of the Invention]

[0013] In short, when releasing the brake lever, the brake lever, which is locked by a locking mechanism at the braking position close to the steering mechanism, is operated to the closest position, which is even closer to the steering mechanism. This releases the locking mechanism at the braking position, and the locking mechanism automatically moves from the locked position to the released position due to the biasing force of the biasing means. Therefore, when releasing the brake lever, it is unnecessary to operate the locking mechanism from the locked position where it locks the brake lever at the braking position to the released position where the brake lever is released. As a result, when releasing the brake lever, it is only necessary to operate the brake lever to the closest position, and this operation of the brake lever to the closest position automatically moves the locking mechanism from the locked position to the released position.

[0014] Furthermore, when releasing the brake lever, if the brake lever, which is locked in contact with the steering section from below by a hook-shaped locking part at the braking position close to the steering section, is operated to an even higher, closest position relative to the steering section, the downward locking of the brake lever by the hook part is released, restricting the movement of the brake lever from the braking position to a lower, separated position. The locking part, whose movement was restricted at the locked position by the locking of the brake lever by the locking of the hook part, then automatically moves to the unlocked position by the biasing force of the biasing means. As a result, when releasing the brake lever, the locking part can be automatically moved from the locked position to the unlocked position simply by operating the brake lever to an even higher, closest position.

[0015] In contrast, when releasing the brake lever, if the brake lever, which is locked in contact with the steering section from the front by the hook at the braking position, is operated to the closest position, which is even closer to the steering section, the locking of the brake lever by the hook, which had been restricting its movement from the braking position to the forward, separated position, is released, and the locking part automatically moves to the released position by the biasing force of the biasing means. As a result, when releasing the brake lever, the locking part can be automatically moved from the locked position to the released position simply by operating the brake lever further backward to the closest position.

[0016] Furthermore, a coil spring is used as a biasing means, wound around a portion of the steering section. One end of this coil spring is fixed to the steering section, and the other end is fixed to a locking part. The coil spring is extended when the locking part locks the brake lever in the braking position, and when the locking part releases the brake position, the coil spring contracts, applying a biasing force to the locking part. As a result, when the brake lever is operated to its closest position to release the brake, the biasing force of the coil spring allows the locking part to move smoothly from the locked position to the unlocked position.

[0017] Also, in a slider that approaches or separates from the steering unit in conjunction with the operation of the braking lever, a brake pad is connected to a sliding body that is slidable via a wire, and when the braking lever is operated toward the braking position, the sliding body is brought into contact with the bottom of the slider via an elastic body that can expand and contract. Therefore, when the braking lever is accidentally and rapidly operated to the braking position, the sliding body elastically contacts the bottom of the slider via the elastic body, and the pressing contact of the brake pads against the left and right rear wheels is alleviated. As a result, it is possible to prevent sudden braking due to an incorrect operation of the braking lever to the braking position.

Brief Description of the Drawings

[0018] [Figure 1] It is a perspective view of a pushcart equipped with a locking device according to the first embodiment of the present invention, viewed obliquely from the front right side at the separated position of the braking lever. [Figure 2] It is a front view of the pushcart of FIG. 1 viewed from the front. [Figure 3] It is a right side view of the pushcart of FIG. 1 viewed from the right side. [Figure 4] It is a rear view of the pushcart of FIG. 1 viewed from the rear. [Figure 5] It is a perspective view of the pushcart of FIG. 1 viewed obliquely from the front left side. [Figure 6] It is a plan view of the pushcart of FIG. 5 viewed from above. [Figure 7] It is a perspective view of the pushcart of FIG. 1 viewed obliquely from the front right side at the braking position of the braking lever. [Figure 8] It is a front view of the pushcart of FIG. 7 viewed from the front. [Figure 9] It is a right side view of the pushcart of FIG. 7 viewed from the right side. [Figure 10] It is a perspective view of the pushcart of FIG. 9 viewed obliquely from the front left side. [Figure 11] It is a plan view of the pushcart of FIG. 10 viewed from above. [Figure 12] It is a cross-sectional view taken along line A-A of FIG. 6. [Figure 13] It is a cross-sectional view taken along line B-B of FIG. 11. [Figure 14] This is a cross-sectional view taken along the CC line in Figure 2. [Figure 15] This is a cross-sectional view taken along the DD line in Figure 8. [Figure 16] This is a perspective view of a pushcart equipped with a locking device according to a second embodiment of the present invention, viewed from the diagonal front right side with the brake lever in a separated position. [Figure 17] Figure 16 is a front view of the handcart, seen from the front. [Figure 18] Figure 16 is a right side view of the handcart, seen from the right side. [Figure 19] Figure 16 is a rear view of the handcart, seen from the rear. [Figure 20] Figure 16 is a perspective view of the handcart, seen from the diagonal front right with the brake lever in the braking position. [Figure 21] Figure 20 is a front view of the handcart, seen from the front. [Figure 22] Figure 20 is a right side view of the handcart, seen from the right side. [Figure 23] This is a cross-sectional view taken along the EE line in Figure 17. [Figure 24] This is a cross-sectional view taken along the FF line in Figure 21. [Figure 25] This is a cross-sectional view taken along the GG line in Figure 17. [Figure 26] This is a cross-sectional view taken along the HH line in Figure 21. [Modes for carrying out the invention]

[0019] Hereinafter, a handcart according to an embodiment of the present invention will be described based on the drawings.

[0020] Figure 1 shows a perspective view of a hand truck equipped with a locking device according to the first embodiment of the present invention, viewed from the front right at the distanced position of the brake lever. Figure 2 shows a front view of the hand truck in Figure 1, Figure 3 shows a right side view of the hand truck in Figure 1, viewed from the right, and Figure 4 shows a rear view of the hand truck in Figure 1. Furthermore, Figure 5 shows a perspective view of the hand truck in Figure 1, viewed from the front left, and Figure 6 shows a top view of the hand truck in Figure 5.

[0021] As shown in Figures 1 to 6, the pushcart 1A is used as a mobility aid and is equipped with a handle section 11 at its upper end as a steering section. This handle section 11 extends to the left and right so that it is easy for the user to grasp. The pushcart 1A also has handle brackets 10, 10 that extend downward from both the left and right ends of the handle section 11, and handle frames 12, 12 that extend downward from these left and right handle brackets 10, 10 as steering frames. Each handle bracket 10 consists of an upper part 101 that extends straight up and down, and a lower part 102 that extends straight down while being bent inward from the upper part 101.

[0022] The handle section 11 is composed of a cylindrical core material 111 and a cylindrical outer surface material 110 that covers the periphery of the core material 111. The left and right handle frames 12, 12 each consist of upper handle frame sections 121, 121 attached to the lower part 102 of the handle bracket 10, and lower handle frame sections 122 extending downward from the lower ends of each upper handle frame section 121. Each handle frame 12 is fixed in an optimal position with the upper end of each lower handle frame section 122 inserted through the lower end of each upper handle frame section 121 in a length-adjustable manner.

[0023] Furthermore, the lower ends of each lower handle frame section 122 are fixed in place by being inserted through both the left and right ends of a roughly U-shaped frame 123 that opens upward. The upper ends of both the left and right sides of this U-shaped frame 123 are firmly connected by an upper horizontal frame 124 that extends in the left-right direction.

[0024] Leg support brackets 13, 13 are fixed to the lower parts of both the left and right sides of the U-shaped frame 123, that is, approximately in the center in the vertical direction. The upper ends of the front leg frames 14, 14 are rotatably supported at the lower front ends of these left and right leg support brackets 13, 13 via horizontal pins 141. Furthermore, the left and right leg support brackets 13, 13 are firmly connected by a lower transverse frame 125 that extends horizontally between the approximately midpoints of both the left and right sides of the U-shaped frame 123.

[0025] Each front wheel frame 14 includes an upper straight section 142 extending approximately horizontally forward from the lower front end of each leg support bracket 13, and a lower straight section 143 extending diagonally forward and downward from the front end of the upper straight section 142. The lower end of each lower straight section 143 is supported so as to allow for free rotation of the front wheel 14F. The lower ends of each front wheel frame 14 are firmly connected to each other by a front transverse frame 144 extending in the left-right direction.

[0026] The upper ends of the rear wheel leg frames 15, 15 are rotatably supported at the lower rear ends of the left and right leg support brackets 13, 13 via horizontal pins 151. Each rear wheel leg frame 15 is formed in a straight line extending diagonally backward and downward from the lower rear ends of each leg support bracket 13, and the rear wheels 15R are rotatably supported at their lower ends. The lower ends of each rear wheel leg frame 15 are firmly connected to each other by a rear transverse frame 152 that extends in the left-right direction.

[0027] Furthermore, brake pads 16 for braking each rear wheel 15R are rotatably supported at the lower end of each rear wheel frame 15. Below the handlebars 11, brake levers 18 (braking levers) extending in the left-right direction are provided. Both ends of these brake levers 18 are supported by the respective handlebar brackets 10, and they are operated to slide freely up and down along the handlebar frames 12 below the handlebars 11. When the brake levers 18 are in a position separated downward from the handlebars 11, the brake pads 16 do not come into contact with each rear wheel 15R, thus maintaining a state where the vehicle can be driven.

[0028] Between the upper straight sections 142 of each front wheel leg frame 14, a seat surface 17 is provided where a user can sit. The seat surface 17 includes a roughly U-shaped seat frame 171 that opens to the rear. This seat frame 171 is rotatably supported at the upper front end of each leg support bracket 13 via a horizontal axis 172. The seat frame 171 is held in a horizontal position where it can be seated by contacting the upper straight section 142 of each front wheel leg frame 14.

[0029] Furthermore, a pair of left and right folding links 3, 3 are provided between the middle of the lower straight section 143 of each front wheel frame 14 and the middle of each rear wheel frame 15, for folding each front wheel frame 14 and each rear wheel frame 15 against the left and right sides of the U-shaped frame 123. Each folding link 3 includes a front link 31 whose front end is rotatably supported at the middle of the lower straight section 143 of the front wheel frame 14 and extends to the rear, and a rear link 32 whose rear end is rotatably supported at the middle of the rear wheel frame 15 and extends to the front.

[0030] The rear end of each front link 31 and the front end of each rear link 32 are rotatably supported via a horizontal axis 33 that extends in the left-right direction. This horizontal axis 33 is supported at the lower end of extension links 34 that extend downward from both the left and right ends of the U-shaped frame 123. Each front link 31 and each rear link 32 can be converted between a state in which they can travel around the horizontal axis 33 and a folded state via the extension links 34 on both the left and right sides of the U-shaped frame 123.

[0031] Figure 7 shows a perspective view of the wheelbarrow 1A from Figure 1, viewed from the front right at the braking position of the brake lever. Figure 8 shows a front view of the wheelbarrow 1A from Figure 7, and Figure 9 shows a right side view of the wheelbarrow 1A from the right. Furthermore, Figure 10 shows a perspective view of the wheelbarrow 1A from Figure 9, viewed from the front left, and Figure 11 shows a top view of the wheelbarrow 1A from Figure 10.

[0032] As shown in Figures 7 to 11, when the brake lever 18 is pulled up from a drivable distance position (the position shown in Figures 1 to 6) toward the handlebars 11 (upwards), it moves to a braking position (the position shown in Figures 7 to 11) that approaches the handlebars 11 from below. When the brake lever 18 is pulled up to the braking position, each brake pad 16 is activated to press against each rear wheel 15R via a brake operating wire W (wire), thereby braking each rear wheel 15R. Each brake operating wire W is inserted into a tube WT that slidably covers its outside. In this case, the front ends of each brake pad 16 are connected to each other via a brake rod 19 that extends in the left-right direction, and the lower ends of each brake operating wire W are connected to both the left and right ends of this brake rod 19.

[0033] Figure 12 shows a cross-sectional view taken along line AA in Figure 6, and Figure 13 shows a cross-sectional view taken along line BB in Figure 11. As shown in Figures 12 and 13, the upper portion 101 of each handle bracket 10 is provided with rectangular chambers 21 that extend linearly vertically within the operable range of the brake lever 18 at both the left and right ends of the brake lever 18. Each of these chambers 21 is provided with a rectangular slider 22 that slides vertically within the chamber 21. The inner surfaces of the upper portion 101 of each handle bracket 10 are open in directions facing each other (towards the brake lever 18). The left and right ends of the brake lever 18 are connected to the outer circumferential wall of each slider 22 via openings in the inner surfaces of the upper portion 101 of each handle bracket 10, and the sliders 22 move vertically within each chamber 21 as the brake lever 18 is operated vertically.

[0034] Each slider 22 houses a sliding body 23, to which the upper end of the brake operating wire W is connected to the lower surface, so as to be able to slide vertically within the interior of each slider 22. A compression spring 24, acting as an elastic body, is compressed between the bottom of the slider 22 and the lower surface of the sliding body 23. When the brake lever 18 is operated toward the braking position, the sliding body 23 elastically contacts the bottom of the slider 22 via the compression spring 24, and the brake lever 18 and the brake operating wire W are elastically connected via the compression spring 24.

[0035] Figure 14 shows a cross-sectional view taken along the CC line in Figure 2, and Figure 15 shows a cross-sectional view taken along the DD line in Figure 8. As shown in Figures 14 and 15, a locking mechanism 4 is provided in the left-right center of the handle section 11 to lock the brake lever 18 in the braking position so that the left and right rear wheels 15R, 15R cannot roll due to contact with the brake pads 16.

[0036] The locking mechanism 4 is housed in an annular groove 40 in which the outer surface material 110 is cut circumferentially to the core material 111 at the left-right center of the handle portion 11. This locking mechanism 4 is rotatably supported around the axis of the core material 111 of the handle portion 11 and includes a locking portion 41 that locks the brake lever 18 into and out of the braking position, and a coil spring 42 as a biasing means that biases the locking portion 41 from the locking position (shown in Figure 15) where the brake lever 18 is locked in the braking position to the unlocked position (shown in Figure 14) where the brake of the brake lever 18 is released. In this case, the groove 40 in the left-right center of the handle portion 11 is approximately the same width as the locking portion 41.

[0037] The locking portion 41 has a notched groove 43 cut out within a range of approximately 40° in its circumferential direction, and a fixing pin member 44 fixed to the core material 111 of the handle portion 11 via this notched groove 43 allows rotation around the axis within the circumferential range of the notched groove 43. In addition, the locking portion 41 has a hook portion 45 projecting radially outward that locks the brake lever 18 in a state where it is in contact with the center of the brake lever 18 from below, so as to restrict the movement of the brake lever 18 to a lower, separated position in the braking position. The hook portion 45 can be converted by rotation of the locking portion 41 between a locking position (shown in Figure 15) in which the brake lever 18 is locked from below within the range of the notched groove 43, and a release position (shown in Figure 14) in which the locking from below with the brake lever 18 is released.

[0038] The coil spring 42 is wound around approximately half the circumference of the locking portion 41, with one end fixed to the fixing pin member 44 (handle portion 11) and the other end fixed to the base of the hook portion 45. The coil spring 42 extends when the brake lever 18 is locked in the braking position by the hook portion 45, and contracts when the locking in the braking position by the hook portion 45 is released. The biasing force during this contraction biases the hook portion 45 (locking portion 41) toward the unlocked position. In this case, the locking portion 41 is held in the locked position against the biasing force of the coil spring 42 by contacting the center of the brake lever 18 from below, as if embracing it, when the hook portion 45 is in the locked position.

[0039] Furthermore, the slider 22 in each handle bracket 10 is housed within the chamber 21 with a gap S (see Figure 13) at the top when the brake lever 18 is locked in the braking position. In other words, the brake lever 18 can slide upwards on the slider 22 by the amount of the gap S at the top within the chamber 21, thereby allowing it to be operated from the braking position that brakes each rear wheel 15R to the closest position that is even closer to the handle section 11.

[0040] In short, when the brake lever 18 is operated from the locked braking position to the closest position, a vertical space is created between the brake lever 18 in the braking position and the hook portion 45 that was holding it from below in the locking position. As a result, the locking portion 41 automatically moves from the locking position to the unlocked position by the biasing force of the coil spring 42, and the brake lever 18 is returned to the separated position.

[0041] Therefore, in this embodiment, when releasing the brake of the brake lever 18, the brake lever 18, which is locked from below by the hook portion 45 of the locking portion 41 in the braking position where it approaches the handle portion 11 from below, is operated upward to the closest position where it is even closer to the handle portion 11. This creates a vertical space between the hook portion 45 and the brake lever 18, and the locking portion 41 automatically moves from the locked position to the unlocked position by the biasing force of the coil spring 42, returning the brake lever 18 to the separated position. For this reason, when releasing the brake of the brake lever 18 in the braking position, it is unnecessary to release the locking portion 41 from the locked position where it locks the brake lever 18 in the braking position to the unlocked position where the brake of the brake lever 18 is released. As a result, when releasing the brake of the brake lever 18, it is only necessary to operate the brake lever 18 to the closest position, and this operation of the brake lever 18 to the closest position allows the locking portion 41 to automatically move from the locked position to the unlocked position.

[0042] Furthermore, the coil spring 42 is wound around approximately half the circumference of the locking portion 41, with one end fixed to the fixing pin member 44 and the other end fixed to the base of the hook portion 45. The coil spring extends at the locking position of the locking portion 41 that locks the brake lever 18 in the braking position, and contracts when the locking at the braking position by the locking portion 41 is released, thereby applying a biasing force to the locking portion 41. As a result, when the brake lever 18 is operated to its closest position to release the brake, the biasing force of the coil spring 42 allows the locking portion 41 to move smoothly to the unlocked position.

[0043] Furthermore, a brake pad 16 is connected via a brake operating wire W to a sliding body 23 that is slidable within a slider 22 that moves closer to or further away from the handle 11 in conjunction with the operation of the brake lever 18. When the brake lever 18 is operated toward the braking position, the sliding body 23 is brought into contact with the bottom of the slider 22 via an expandable and contractible compression spring 24. As a result, if the brake lever 18 is accidentally and suddenly moved toward the braking position, the sliding body 23 elastically contacts the bottom of the slider 22 via the compression spring 24, and the pressure of the brake pad 16 against the left and right rear wheels 15R, 15R is reduced. This prevents sudden braking caused by erroneous operation of the brake lever 18 toward the braking position.

[0044] Next, a second embodiment of the present invention will be described based on the drawings.

[0045] Figure 16 shows a perspective view of a hand truck equipped with a locking device according to the second embodiment of the present invention, viewed from the diagonal front right with the brake lever in a separated position. Figure 17 shows a front view of the hand truck in Figure 16, Figure 18 shows a right side view of the hand truck in Figure 16, and Figure 19 shows a rear view of the hand truck in Figure 16.

[0046] As shown in Figures 16 to 19, the pushcart 1B is used as a mobility aid and is equipped with a handle section 51 at its upper end as a steering section. This handle section 51 includes a handle bar 511 that extends straight in the left-right direction for easy gripping by the user, and support pieces 512, 512 that protrude downward from both ends of the handle bar 511. The handle bar 511 is composed of a cylindrical core material 510 and a cylindrical outer surface material 513 that covers the periphery of this core material 510.

[0047] Furthermore, the handcart 1B is equipped with a handle frame 52, which serves as a steering frame, with its upper end connected to the lower end of each support piece 512 of the handle section 51 via a handle bracket 50. Each handle frame 52 extends straight downward from the handle bracket 50.

[0048] Each handle frame 52 is fixed in an optimal position with the upper ends of a pair of left and right front wheel leg frames 53, 53 (leg frames) that extend vertically through its lower end, with their lengths adjustable. Each front wheel leg frame 53 includes an upper straight section 531 that extends straight vertically from the lower end of the handle frame 52, and a lower straight section 533 that extends diagonally forward and downward from the lower end of the upper straight section 531, with a bent section 532 in between.

[0049] Each front wheel 14F is supported at the lower end of the lower straight section 533 of each front wheel frame 53 so as to be able to roll freely. The lower ends of each lower straight section 533 are firmly connected to each other by a horizontal frame 530 that extends in the left-right direction.

[0050] A leg bracket 534 is fixed to the lower end of the upper straight section 531 of each front wheel leg frame 53, and the upper ends of a pair of left and right rear wheel leg frames 55, 55 (leg frames) extending diagonally downward and rearward are each supported by this leg bracket 534 so as to be rotatable around a horizontal axis 551. A rear wheel 15R is supported at the lower end of each rear wheel leg frame 55 so as to be rotatable. The lower ends of each rear wheel leg frame 55 are firmly connected to each other by a lateral frame 552 extending in the left-right direction.

[0051] Furthermore, a brake pad 16 for braking each rear wheel 15R is rotatably supported at the lower end of each rear wheel frame 55. A brake lever 59 extending in the left-right direction is rotatably supported on the front side of the handlebar 511 of the handle section 51, around the horizontal axis at both ends. When the brake lever 59 is rotated to pull it towards the handle section 51 (towards the rider), each brake pad 16 is activated via the brake operating wire W, thereby braking the rear wheel 15R.

[0052] Between the lower ends of the upper straight sections 531 of each front wheel frame 53, a seat surface 56 is provided on which a user can sit. The seat surface 56 is equipped with a roughly U-shaped seat frame 57 that opens to the rear.

[0053] The seat frame 57 comprises a pair of left and right side frame pieces 572, 572, each rotatably supported via a horizontal axis 571 at a position slightly rearward from the center in the front-to-back direction on each leg bracket 534 at the lower end of the upper straight portion 531 of each front wheel leg frame 53, and a front connecting frame piece 573 that connects the tips (front ends) of each side frame piece 572. Furthermore, the base ends (rear ends) of the left and right side frame pieces 572, 572 of the seat frame 57 are connected by a rear connecting frame piece 574 that extends in the left-to-right direction.

[0054] Furthermore, a pair of left and right folding links 6, 6 are provided between the lower end of the lower straight section 533 of each front wheel frame 53 and the lower end of each rear wheel frame 55, for folding each rear wheel frame 55 relative to each front wheel frame 53. Each folding link 6 comprises a front link 61 whose front end is rotatably supported at the lower end of the lower straight section 533 of the front wheel frame 53 and extends rearward, and a rear link 62 whose rear end is rotatably supported at the lower end of the rear wheel frame 55 and extends forward.

[0055] The front link 61 and the rear link 62 are rotatably supported via a horizontal axis 63 extending in the left-right direction. The front end of the rear link 62 abuts against a projection 611 that protrudes approximately horizontally from the rear end of the front link 61, thereby holding each rear wheel frame 55 in a drivable state relative to each front wheel frame 53. A biasing spring 64 is stretched between the projection protruding from the rear end of the front link 61 and the rear link 62, which is located slightly forward of the center. The biasing force of this biasing spring 64 holds each rear wheel frame 55 in a drivable state and a folded state relative to each front wheel frame 53.

[0056] Furthermore, a pair of vertical links 65, 65 extending vertically are rotatably connected between the intermediate position of each front link 61 and the front side of each side frame piece 572 of the seat frame 57 via upper and lower horizontal axes 651, 652. When the seat frame 57 is rotated around the horizontal axis 571, the front link 61 and the rear link 62 flex and extend in conjunction with this rotation, converting each rear wheel frame 55 between a drivable state and a folded state relative to each front wheel frame 53.

[0057] Figure 20 shows a perspective view of the hand truck from Figure 16, viewed from the front right at the braking position of the brake lever. Figure 21 shows a front view of the hand truck from Figure 20, and Figure 22 shows a right side view of the hand truck from Figure 20, viewed from the right.

[0058] As shown in Figures 20 to 22, the brake lever 59 is formed in a roughly U-shape that opens downwards and is rotatably supported on each handle bracket 50 at the upper end of each handle frame 52. Furthermore, when the brake lever 59 is operated to pull it towards the handle section 11 (rearward) from a drivable distance position (position shown in Figures 16 to 19), it rotates to a braking position (position shown in Figures 20 to 22) where it approaches the handle bar 511 of the handle section 51 from the front. When the brake lever 59 is pulled to the braking position, each brake pad 16 is operated to press against each rear wheel 15R via the brake operating wire W, thereby braking each rear wheel 15R.

[0059] Figure 23 shows a cross-sectional view taken along the line EE in Figure 17, and Figure 24 shows a cross-sectional view taken along the line FF in Figure 21. As shown in Figures 23 and 24, projections 591 projecting backward are integrally provided at both the left and right ends of the brake lever 59. The tip (rear end) of each projection 591 is supported by a horizontal axis 592 extending in the left-right direction relative to each handle bracket 50. Each handle bracket 50 is provided with a projection 501 projecting forward.

[0060] The upper surface of the projection 501 of each handle bracket 50 and the lower front portion of each projection 591 of the brake lever 59 are formed as flat surfaces that come into contact without gap when the brake lever 59 is in a spaced position, separated forward from the handlebar 511. In other words, the brake lever 59 is held in a spaced position with the lower front portion of each projection 591 in contact with the upper surface of the projection 501 of each handle bracket 50.

[0061] Each handle bracket 50 is provided with a projection 501 that has an insertion hole 502 for fixing the upper end of the tube WT of the brake operating wire W, and the upper end of the brake operating wire W is led out through the insertion hole 502 to the lower front side of each projection 591 of the brake lever 59. The upper end of the brake operating wire W is attached to the lower front of each projection 591 of the brake lever 59. When the brake lever 59 is pulled from a position away from the handlebar 511 to a braking position, the lower front of each projection 591 of the brake lever 59 moves away from the upper surface of the projection 501 of each handle bracket 50 by rotation around the horizontal axis 592, the brake operating wire W is pulled out from the tube WT, and each rear wheel 15R is braked by each brake pad 16.

[0062] Figure 25 shows a cross-sectional view taken along the GG line in Figure 17, and Figure 26 shows a cross-sectional view taken along the HH line in Figure 21. As shown in Figures 25 and 26, a locking mechanism 7 is provided at the left-right center of the handlebar 511 of the handle section 51, which locks the brake lever 59 in the braking position so that the left and right rear wheels 15R, 15R cannot roll due to contact with the brake pads 16.

[0063] The locking mechanism 7 is housed in an annular groove 70 in which the outer surface material 513 is cut circumferentially down to the core material 510 at the left-right center of the handlebar 511. The locking mechanism 7 is rotatably supported around the axis of the core material 510 of the handlebar 511 and includes a locking portion 71 that locks the brake lever 18 into and out of the braking position, and a coil spring 72 as a biasing means that biases the locking portion 71 from the locking position (shown in Figures 24 and 26) where the brake lever 59 is locked in the braking position to the unlocked position (shown in Figures 23 and 25) where the brake of the brake lever 59 is released. In this case, the groove 70 in the left-right center of the handlebar 511 is approximately the same width as the locking portion 71.

[0064] The locking portion 71 has a notched groove 73 cut out in the circumferential direction, and a fixing pin member 74 fixed to the reduced diameter portion 510 of the handlebar 511 via this notched groove 73 allows rotation around the axis within a predetermined range in the circumferential direction of the notched groove 73 (for example, within about 50°). In addition, the locking portion 71 has a hook portion 75 projecting radially outward that locks the brake lever 59 in a state where it is in contact with the center of the brake lever 59 from the front, so as to restrict the movement of the brake lever 59 to a forward separated position in the braking position. The hook portion 75 can be converted between a locking position (shown in Figures 24 and 26) in which the brake lever 59 is locked from the front within a predetermined range in the circumferential direction of the notched groove 73, and a release position (shown in Figures 23 and 25) in which the locking from the front with respect to the brake lever 59 is released.

[0065] The coil spring 72 is wound around approximately half the circumference of the locking portion 71, with one end fixed to the fixing pin member 74 (handle portion 51) and the other end fixed to the base of the hook portion 75. The coil spring 72 extends when the brake lever 59 is locked in the braking position by the hook portion 75, and contracts when the locking in the braking position by the hook portion 75 is released. The biasing force during this contraction biases the hook portion 75 (locking portion 71) toward the unlocked position. In this case, the locking portion 71 is held in the locked position against the biasing force of the coil spring 72 by contacting the center of the brake lever 59 from the front when the hook portion 75 is in the locked position, as if embracing it.

[0066] Furthermore, the brake lever 59 is set to be operated to its closest position, which is even closer to the handle 51 from the front when it is locked by the locking part 71 in the braking position. In short, when the brake lever 59 is operated from the locked state in the braking position to the closest position, a space is created in the front-rear direction between the brake lever 59 in the braking position and the hook part 75 which was gripping it from the front in the locking position. The locking part 71 then moves automatically from the locking position to the unlocked position by the biasing force of the coil spring 72, and the brake lever 59 is returned to the separated position.

[0067] Therefore, in this embodiment, when releasing the brake of the brake lever 59, the brake lever 59, which is locked in a position where it is close to the handlebar 511 by the hook portion 75 from the front, is operated to the closest position, which is even closer to the handlebar 511. This releases the contact between the brake lever 59 and the hook portion 75, which had been restricting the movement of the brake lever 59 from the braking position to the forward, separated position. As a result, the locking portion 71, whose movement was restricted in the locked position by contact with the brake lever 59, automatically moves to the unlocked position due to the biasing force of the coil spring 72. Thus, when releasing the brake of the brake lever 59, the locking portion 71 can be automatically moved from the locked position to the unlocked position simply by operating the brake lever 59 to the closest position further forward.

[0068] It should be noted that the present invention is not limited to the embodiments described above, but encompasses various other modifications. For example, although the embodiments described above describe the application to a mobility scooter 1A, 1B equipped with locking devices 4, 7, a stroller or other type of mobility scooter may also be used.

[0069] Furthermore, in each of the above embodiments, coil springs 42 and 72 were used as biasing means for the locking mechanisms 4 and 7, but an elastic body such as rubber may also be used as the biasing means.

[0070] Furthermore, in the first embodiment described above, a compression spring 24 is compressed between the bottom of the slider 22 in each chamber 21 at both ends of the brake lever 18 and the sliding body 23, but an elastic material such as rubber may be compressed instead.

[0071] Furthermore, in each of the above embodiments, the locking mechanisms 4 and 7 are housed in annular grooves 40 and 70 in which the outer surface material 110 and 513 is cut circumferentially down to the core material 111 and 510 at the left-right center of the handle portion 11 and 51. However, the locking mechanisms may also be directly attached to the handle portion made of a single pipe. [Explanation of Symbols]

[0072] 1A Handcart 1B Handcart 11. Steering section (steering mechanism) 12. Handle frame (steering frame) 13. Front wheel leg frame (leg frame) 14F front wheel 15. Rear wheel leg frame (leg frame) 15R Rear Wheel 18. Brake lever (brake lever) 22 Sliders 23 Sliding body 24. Compression spring (elastic body) 4. Locking mechanism 41 Locking part 42 Coil spring (biasing means) 45 Hook section 51. Steering wheel section (steering mechanism) 52. Steering frame 53 Front wheel leg frame (leg frame) 55 Rear wheel leg frame (leg frame) 59 Brake lever (brake lever) 7. Locking mechanism 71 Locking part 72 Coil spring (biasing means) 75 Hook section W Brake operating wire (wire)

Claims

1. In a handcart, which is provided with left and right steering frames extending downward from a steering section that the user grasps with both hands, and left and right leg frames connected to the lower ends of these two steering frames, which support the front and rear wheels so that they can roll freely, At a position separated from the steering unit, a braking lever is provided which is operated toward a braking position that approaches the steering unit in order to brake the left and right rear wheels of the front and rear wheels. The steering unit is provided with a locking mechanism that locks the brake lever in the brake position so that the left and right rear wheels cannot roll. The braking lever is set to be operable from the braking position to the closest position, which is even closer to the steering unit, The locking mechanism is A locking part that allows the aforementioned brake lever to be locked and unlocked in the brake position, A biasing means that biases the locking portion from a locking position that locks the brake lever at the braking position to a release position where the brake of the brake lever is released, It has, The braking lever is supported below the steering unit and is slidable vertically along each steering frame. It is operated from a position separated from the steering unit downwards to a braking position approaching the steering unit from below, and from this braking position to a position closer to the steering unit from further below. The locking portion is rotatably supported around the axis of the steering portion and has a hook portion that locks the brake lever by embracing it from below so as to restrict the movement of the brake lever from the brake position to a lower, separated position, and when the brake lever is operated upward from the brake position to the closest position, a vertical space is created between the brake lever at the brake position and the hook portion that was embracing it from below, causing the locking portion to automatically move from the locking position to the unlocked position by the biasing force of the biasing means, thereby returning the brake lever to the separated position.

2. A handcart provided with left and right steering frames extending downward from a steering section that the user grasps with both hands, and left and right leg frames connected to the lower ends of both steering frames, which support the front and rear wheels so that they can roll freely, At a position separated from the steering unit, a braking lever is provided which is operated toward a braking position that approaches the steering unit in order to brake the left and right rear wheels of the front and rear wheels. The steering unit is provided with a locking mechanism that locks the brake lever in the brake position so that the left and right rear wheels cannot roll. The braking lever is set to be operable from the braking position to the closest position, which is even closer to the steering unit, The locking mechanism is A locking part that allows the aforementioned brake lever to be locked and unlocked in the brake position, A biasing means that biases the locking portion from a locking position that locks the brake lever at the braking position to a release position where the brake of the brake lever is released, It has, The braking lever is rotatably supported around a horizontal axis extending in the left-right direction at the midpoint of the vertical direction of each steering frame, and is operated from a position separated from the steering unit, which is further forward, to a braking position, which is closer to the steering unit, and from this braking position to a position closer to the steering unit, which is even closer to the steering unit. The locking portion is rotatably supported around the axis of the steering portion and has a hook portion that locks the brake lever by embracing it from the front so as to restrict the movement of the brake lever from the brake position to a forward distance position, and when the brake lever is operated backward from the brake position to the closest position, a space is created in the front-rear direction between the brake lever at the brake position and the hook portion that was embracing it from the front, causing the locking portion to automatically move from the locking position to the release position by the biasing force of the biasing means, and the brake lever to return to the distance position.

3. The biasing means is a coil spring which is wound around a part of the perimeter of the steering part, with one end fixed to the steering part and the other end fixed to the locking part. The wheelbarrow locking device according to claim 1 or claim 2, wherein the coil spring extends when the braking lever is locked in the braking position by the hook portion, and contracts when the locking in the braking position by the hook portion is released, thereby acting a biasing force on the lock portion.

4. The brake lever is connected to a slider that moves linearly up and down from a distanced position to the closest position of the brake lever, and the slider is provided with a sliding body that slides up and down inside it. The sliding body is connected via a wire to brake pads that press against the left and right rear wheels when the brake lever is in the braking position, and the slider moves closer to the steering unit when the brake lever is operated toward the braking position, while the slider moves away from the steering unit when the brake lever is separated from the steering unit. The locking device for a pushcart according to claim 1, wherein the sliding body is connected to the lower end of the wire and contacts the bottom of the slider via an expandable and contractible elastic body when the braking lever is operated toward the braking position.

5. The brake lever is connected to a slider that moves linearly up and down from a distanced position to the closest position of the brake lever, and the slider is provided with a sliding body that slides up and down inside it. The sliding body is connected via a wire to brake pads that press against the left and right rear wheels when the brake lever is in the braking position, and the slider moves closer to the steering unit when the brake lever is operated toward the braking position, while the slider moves away from the steering unit when the brake lever is separated from the steering unit. The locking device for a pushcart according to claim 3, wherein the sliding body is connected to the lower end of the wire and contacts the bottom of the slider via an expandable and contractible elastic body when the braking lever is operated toward the braking position.

Images