JP2004082920A - Braking device for handcart - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a braking device positively regulating and maintaining movement of a handcart. <P>SOLUTION: In the braking device for the handcart, a base end part of a brake shoe 7 approaching and separating from a fixed wheel 2'A with a tip receiving and supporting a loading space 1 is turnably pivotally attached by a first spindle 6 to a front end side of a support piece 5A suspended in a rear end side of a bottom face of the loading space 1, and an intermediate part of an operating piece 9 with a rear end part protruding more to the rear than the loading space 1 pressed down by a drive rod 14 is turnably pivotally attached to the rear end side by a second spindle 8. The front end part is rotatably pivotally attached to an intermediate part of the brake shoe 7 by a first connecting pin 20, and a rear end part of a turnably pivotally attached mediating piece 16 and a front end part of the operating piece 9 are rotatably pivotally attached by a second connecting pin 21. A spring 19 turnably energizing the second connecting pin 21 around the second spindle 8 from an upper side position toward a lower side position of an imaginary straight line connecting the first connecting pin 20 and the second spindle is interposed between the operating piece 9 and the loading space 1. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
[Industrial applications]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake device for a hand-carriage vehicle that can release wheels from a braking state and keep the wheels rotatable as required.
[0002]
[Prior art]
For example, Japanese Unexamined Utility Model Publication No. Hei 7-31560 discloses a system in which the wheels are always kept in a braking state, and when a hand truck is used (when carrying luggage), the braking state is released to keep the wheels in a rolling state. There is a structure published in the gazette.
[0003]
In this conventional structure, the base end of a brake shoe is rotatably assembled to a wheel frame provided on a loading platform, and the brake shoe is constantly biased between the brake shoe and the loading platform in a direction of pressing against the wheel. A bar wire is connected to the tip of the brake shoe protruding from the wheel frame, and the bar wire is raised to bring the brake shoe into contact with the wheel against the bias of the compression spring. It is designed to be separated from the position.
[0004]
[Problems to be solved by the invention]
Since the conventional structure has a structure in which the urging force of the spring is directly applied to the brake shoe, the braking force, that is, the strength of the contact resistance of the brake shoe to the wheels depends on the spring force of the spring. Or a change over time, and a uniform product cannot always be obtained. In particular, it is necessary to use a spring having an excessively strong spring to ensure the braking force. If the spring is strong, the arm needs to be released to release the braking state. It doesn't work.
[0005]
The present invention has been conceived to provide a device that can reliably perform braking and release without being affected by aging (spring).
[0006]
[Means for Solving the Problems]
The base end of the brake shoe, whose front end comes into contact with and separates from the fixed wheel that receives and supports the carrier, is attached to the front end of the support piece suspended from the rear end of the lower surface of the carrier with the first support shaft. The intermediate portion of the operating piece whose rear end projecting rearward from the carrier is pressed down by the drive rod is pivotally connected to the second support shaft, respectively, and the front end is firstly attached to the intermediate portion of the brake shoe. A rear end portion of the intermediary piece pivotally connected by a connecting pin and a front end portion of the operating piece are pivotably connected by a second connecting pin, and the second connecting pin is connected to the first connecting pin and the first connecting pin. A spring for biasing the second support shaft to rotate about the second support shaft from the upper position to the lower position of the virtual straight line connecting the second support shaft is interposed between the operating piece and the carrier. Things.
[0007]
[Action]
The second connection is made by the bias of a spring interposed between the operating piece and the loading platform (for example, including the one fixed to the loading platform such as a support piece, in short, including the one integrated with the loading platform). The pin is located below an imaginary straight line connecting the first connecting pin and the second support shaft, and in this state, the tip of the brake shoe presses against a fixed wheel to regulate the rolling of the wheel. When the wheel is released from this restricted state and rolls, the second connecting pin crosses the imaginary line and is turned around the second support shaft to a position above the imaginary line against the bias of the spring. However, during the rotation process, when the second connecting pin overlaps with the imaginary line, a large force is applied to the first connecting pin, that is, the brake shoe, and the tip of the second connecting pin is pressed against the wheel most strongly. Escape from the restricted state is not easily performed, that is, the braking of the wheels is reliably performed and maintained. Then, when the rear end of the operating piece is pressed by the operating rod, the operating piece rotates around the second support shaft against the bias of the spring, and the second connecting pin is positioned above the imaginary line. When it moves upward, the braking state is released and the wheels are in a rolling free state, and when the pressing operation of the rear end of the operating piece by the operating rod is interrupted (stopped), each member is returned to the original state by the bias of the spring, and the brake is again applied. The wheel is braked by the shoe.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Drawings show one embodiment of a brake device of a hand truck according to the present invention, FIG. 1 is a front view of a main part, FIG. 2 is a side view of FIG. 1, FIG. 3 is an enlarged sectional view of a main part, and FIG. FIG. 5 is an enlarged sectional view of a main part when the wheels are in a rolling state, and FIG. 5 is a front view of a cart.
[0009]
The cart 100 according to the embodiment supports the loading platform 1 with a pair of front free wheels 2 and 2 and a pair of fixed rear wheels 2 ′ and 2 ′. Is assembled so as to be freely foldable (the description is omitted because its configuration is publicly known), and a brake device A for braking each of the fixed wheels 2 ′ and 2 ′ is provided.
[0010]
In the figure, reference numeral 4 denotes a wheel frame of the fixed wheel 2 '. The wheel frame 4 constitutes the fixed wheel 2' by rotatably supporting the wheel 2'A by an axle, and constitutes the fixed wheel 2 '. The support frame 5 is fastened to the lower surface of the carrier 1 so that a part of the front end thereof overlaps the inside of the carrier 1 (rear end side) and is suspended.
[0011]
Like the wheel frame 4, the support frame 5 includes a pair of support pieces 5a, 5a opposed to each other in the width direction (left-right direction) of the loading platform 1, and a first support erected on the support pieces 5a, 5a at the front end side. The base end of the brake shoe 7 is pivotally connected to the shaft 6, and the intermediate portion of the operating piece 9 is rotatably connected to the intermediate portion of the operating piece 9 by a second support shaft 8 provided on the rear end side.
[0012]
The brake shoe 7 is provided at the tip of the center piece 10a on the tip side of the shoe main body 10 having a U-shaped cross section composed of a center piece 10a and side pieces 10b, 10b. A shoe bolt 12 provided with a piece 11 is assembled by a pair of adjustment nuts 13 and 13 ′, and a side piece 10 b, 10 b, which is a base end of the shoe main body 10, is formed by the first support shaft 6 as described above. It is pivotally attached to and assembled with the support piece 5a (support frame 5).
[0013]
The shoe bolts 12 constituting the brake shoes 7 are connected to the wheel 2'A by loosening the pair of adjusting nuts 13 and 13 'opposed to each other via the central piece 10a of the shoe main body 10. The adjustment nuts 13 and 13 'can be re-tightened to the center piece 10a at the appropriate place where the stopper nut 11 is moved forward and backward with respect to the wheel 2'A, thereby adjusting the position of the stopper piece 11 with respect to the wheel 2'A. (Adjustment of the pressure contact state) can be performed. Of course, the shoe bolt 12 may be omitted, and the wheel 2'A may be braked so that a part of the shoe body 10 directly contacts the wheel 2'A. Thus, a suitable braking state can always be obtained by following a temporal change such as wear of the wheel 2'A.
[0014]
Like the shoe main body 10, the operating piece 9 has a U-shaped cross section composed of a central piece 9a and a pair of side pieces 9b, 9b, and is interposed between the support pieces 5a, 5a of the support frame 5. The intermediate portion is pivotally attached to the support pieces 5a, 5a by the second support shaft 8 as described above, and projects rearward from the carrier 1 toward the rear end side and is pressed by the drive rod 14. On the other hand, the front end side is rotatably pivotally attached to the intermediate portion of the brake shoe 7 via the mediation piece 16 at the side piece 9b, 9b portion, and the center piece 9a A guide rod 18 having a head with a head penetrated from the lower surface side of the portion and supported by engaging the tip (upper end) with an engagement hole 17 provided in the carrier 1. A spring 19 (a coil spring in the embodiment) is wound around the guide rod 18 to operate with the carrier 1. 9 (the tip of the center piece 9a), the front end side of the operating piece 9 is pivotally urged downward by the spring 19 around the second support shaft 8, and the operation by this urging is performed. The rotation of the piece 9 about the second support shaft 8 is restricted by the brake shoe 7 (specifically, the stopper 11 in the embodiment) being pressed against the wheel 2′A. Of the wheel 2′A is maintained by the urging of the spring 19.
[0015]
The rotation of the operating piece 9 by the spring 19 is urged through the intermediate piece 16, that is, the intermediate piece 16 that connects the side piece 10 b of the shoe main body 10 of the brake shoe 7 and the side piece 9 b of the operating piece 9. And transmitted to the brake shoe 7.
[0016]
The brake shoe main body 10 and the operation piece 9 are connected to each other as described above by the pair of the intermediate pieces 16, 16 superimposed on the outside of the respective side pieces 10 b, 9 b. That is, the front end of the intermediate piece 16 and the intermediate part of the brake shoe main body 10 (brake shoe 7) are connected to the first connecting pin 20 located behind the first support shaft 6, and the rear end of the intermediate piece 16 And the tip of the operating piece 9 are pivotally connected to each other by a second connecting pin 21 located between the second support shaft 8 and the first connecting pin 20 so as to be rotatable with each other. The brake shoes 7 are rotatably connected to each other via an intermediate piece 16.
[0017]
The drive rod 14 is formed of a U-shaped frame comprising a horizontal handle portion 14a and a pair of legs 14b, 14b connected to both ends thereof in the same manner as the operation handle 3. Is supported so as to penetrate through a support piece 22 provided on the leg 3b of the operation handle 3, and the handle 14a is located above the handle 3a of the operation handle 3 and at the same time as the handle 3a. It is arranged in a position where it can be gripped with.
[0018]
When the two handle portions 3a, 14a are gripped by the fingers, the handle portion 3a on the operation handle 3 becomes a fixed side, so that the handle portion 14a on the drive rod 14 located above the handle 3a descends. This lowering causes the legs 14b, 14b to press the pressure-receiving part 15, that is, the rear end side of the operating piece 9 provided for each fixed wheel 2 ', 2', and the operating piece 9 moves the second support shaft 8 When the rear end is turned downward and the front end is turned upward (in the clockwise direction in FIG. 1), the spring 19 rotates against the bias.
[0019]
Since the mediation piece 16 is connected to the front end side of the operation piece 9 by the second connection pin 21, the mediation piece 16 is pulled up as the front end side rotates upward (at this time, the second connection pin 20 The brake shoe 7 moves to a position above an imaginary straight line a connecting the second support shaft 8 and the first connection pin 20), and at the same time, a brake shoe 7 (shoe) having an intermediate portion connected to the leading end side of the intermediate piece 16 by the first connection pin 20. Since the main body 10) is lifted up, the front end side (stopper piece 11 side) of the first support shaft 6 as a whole is separated from the wheel 2′A (half in FIG. 1). When the brake shoe 7 (the tip) of the brake shoe 7 is disengaged from the contact position with the wheel 2'A, the wheel 2'A is released from the braking state, and is in a rollable state. Is to continue pressing the driving rod 14 against the pressure receiving piece 15. Ri is maintained (Fig. 4).
[0020]
When the hand is released from the handle portion 14a of the driving rod 14, the pressure receiving (pressing) state of the pressure receiving portion 15 by the driving rod 14 is released, so that the spring force (pressing force) of the spring 19 is applied to the front end of the operating piece 9. The actuating piece 9 rotates in the opposite direction about the second support shaft 8 (in the counterclockwise direction in FIG. 1). The rotation bias of 19 is transmitted to the brake shoe 7 via the second connecting pin 21, the intermediate piece 16 and the first connecting pin 20 in order, and the brake shoe 7 is applied to the wheel 2 ′ A about the first support shaft 6. The tip side pivots down in the contacting direction (clockwise direction in FIG. 1), and the stopper piece 11, which is a component of the brake shoe 7, presses against the wheel 2'A, and the wheel 2'A rolls. Regulate. In this state, the second connecting pin 21 moves to a position below the imaginary straight line a connecting the second support shaft 8 and the first connecting pin 20, and the brake shoe 7 (stopper piece 11) moves with respect to the wheel 2'A. The pressure contact is reliably maintained (FIG. 2). In the braking state, the rotation of the operation piece 9 about the second support shaft 8 by the bias of the spring 19 is performed by the frame provided between the rear ends of the support pieces 5a and 5a of the support frame 5 in the embodiment. The regulation is performed by contacting the rear end side of the operation piece 9 with the piece 5b. However, instead of the frame piece 5b, the driving rod 14 receives the pressure of the rotation of the operation piece 9 by the spring 19 and regulates it. You may do it. However, depending on the positional relationship between the respective support shafts 6, 8 and the respective connection pins 20, 21, a restricting material such as the frame piece 5b of the operation piece 9 is not necessarily required.
[0021]
In the embodiment, the spring 19 uses a coil spring. However, it is not necessary to limit the spring to the one in this embodiment, and the arrangement position may be appropriately selected. In short, the operating piece 9 is rotated around the second support shaft 8. What is necessary is just a thing of the structure which energizes.
[0022]
【The invention's effect】
Since the present invention is configured as described above, it is possible to provide a brake device that reliably controls and maintains the movement of the wheels, that is, the cart.
[Brief description of the drawings]
FIG. 1 is a front view of a main part.
FIG. 2 is a side view of FIG.
FIG. 3 is an enlarged sectional view of a main part.
FIG. 4 is an enlarged sectional view of a main part when the wheel is in a rolling state.
FIG. 5 is a front view of a hand cart.
DESCRIPTION OF SYMBOLS 1 Load bed 2'A Wheel 5A Support piece 6 First support shaft 7 Brake shoe 8 Second support shaft 9 Working piece 14 Drive rod 16 Intermediate piece 19 Spring 20 First connection pin 21 Second connection pin

Claims (1)

The base end of the brake shoe, whose front end comes into contact with and separates from the fixed wheel that receives and supports the carrier, is attached to the front end of the support piece suspended from the rear end of the lower surface of the carrier with the first support shaft. The intermediate portion of the operating piece whose rear end projecting rearward from the carrier is pressed down by the drive rod is pivotally connected to the second support shaft, respectively, and the front end is firstly attached to the intermediate portion of the brake shoe. A rear end portion of the intermediary piece pivotally connected by a connecting pin and a front end portion of the operating piece are pivotally connected by a second connecting pin so that the second connecting pin is connected to the first connecting pin and the first connecting pin. A hand-carriage vehicle in which a spring for biasing the second support shaft to rotate from the upper position to the lower position of the virtual straight line connecting the second support shaft is interposed between the operation piece and the carrier. Brake equipment.

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