JP3661169B2 - caster - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a caster that is used while being attached to the bottom of a transport device or various transport vehicles.
[0002]
[Prior art]
Conventionally, transportation equipment and various transport vehicles are subjected to impacts when they travel on uneven parts such as roads or get over stepped parts during transportation of their own or luggage. A caster with a cushioning member is attached to the bottom to reduce the impact.
[0003]
Examples of the caster include those described in JP-A-7-329505. In this caster, as shown in FIGS. 14 and 15, the fork 31 is divided into an upper fork 31a and a lower fork 31b, and a lower fork 31b provided with wheels 32 below the upper fork 31a is pivotable. In addition to being supported, the shaft support portion is positioned forward of the vertical axis of the axle, and is provided with a buffer member in which a coil spring 33 is interposed vertically between the upper fork 31a and the lower fork 31b.
[0004]
[Problems to be solved by the invention]
However, since the conventional caster is configured such that the coil spring 33 is interposed between the upper fork 31a and the lower fork 31b as a buffer member in the vertical direction, the length of the interposed coil spring 33 corresponds to the length of the caster. There has been a problem that the noise is intense due to the fact that the coil spring 33 generates a squeak noise when it becomes bulky, travels on uneven parts such as roads, or climbs over a stepped part.
[0005]
In addition, the conventional caster hardly dampens vibrations when traveling on uneven parts such as roads, and the coil spring 33 may resonate, and the resonance causes the amplitude of the coil spring 33 to increase. , Had the problem of shaking tremendously.
[0006]
Therefore, the present invention solves the above-described conventional problems, and does not become bulky, and noise such as squeak noise is generated even when traveling on uneven portions such as roads or overstepped portions. Therefore, the object of the present invention is to provide a caster in which vibrations are mitigated, resonance of a coil spring is suppressed, vibration is reduced, and smooth running is possible.
[0007]
[Means for Solving the Problems]
Therefore, in the caster of the present invention, the fork 1 is divided into an upper fork 1a and a lower fork 1b, and the shaft support holes 4 and 5 formed in the upper and lower parts of the upper fork 1a are replaced with the upper shaft support hole 4 and the lower The shaft support holes 5 are arranged in the order from the front to the rear of the caster, and the shaft support holes 6, 7, 8 formed in the upper, middle, and lower parts of the lower fork 1 b are replaced with the center shaft support hole 7, the upper shaft support hole 6, It is assumed that the lower shaft support hole 8 is arranged in order from the front to the rear of the caster, and the front end portion of the buffer member 9 in which the cylindrical body portion 17a of the coil spring 17 is covered with the vibration isolator 18 is covered by the front support body 19. The rear end portion of the buffer member 9 is surrounded by the rear support body 20, the front and rear ends of the buffer member 9 are supported by the front and rear support bodies 19 and 20, respectively, and the front support body 19 is supported on the upper shaft of the upper fork 1a. while pivotally supported by the hole 4, By supporting the support 20 on the top of the shaft supporting hole 6 of the lower fork 1b, and those placed laterally buffer member 9 to the upper fork 1a as telescopic, the lower portion of the upper fork 1a shaft supporting hole 5 and the lower fork 1b are inserted into the shaft support hole 7 in the middle portion of the lower fork 1 so that the upper fork 1a and the lower fork 1b can be rotated. Further, the axle 11 is inserted into the lower shaft support hole 8 of the lower fork 1b. The wheel 12 is pivotally supported.
[0008]
Further, in the caster of the present invention, the support pin 21 is loosely penetrated into the cylindrical body portion 17a of the coil spring 17, and the front end of the support pin 21 is pivotally supported by the front support 19 and the rear end is pivotally supported by the rear support 20. It is assumed that
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of casters according to the present invention will be described below in detail with reference to the drawings.
[0010]
In the caster of the present invention, as shown in FIGS. 1 to 4, the fork 1 is divided into an upper fork 1 a and a lower fork 1 b, and the upper fork 1 a is fixed to the bottoms of transport equipment and various transport vehicles. It is assumed that the bearing 2 is attached to the lower side of the pedestal 2 so as to be rotatable. As shown in FIGS. 5 and 6, shaft support holes 4 and 5 are formed in the upper and lower portions of the upper fork 1a, and these shaft support holes 4 and 5 are connected to the upper shaft support hole 4 and the lower shaft support. As shown in FIGS. 7 and 8, shaft support holes 6, 7, and 8 are formed in the upper, middle, and lower portions of the lower fork 1 b in the order of the holes 5 from the front to the rear of the caster. The holes 6, 7, 8 are arranged in the order of the middle shaft support hole 7, the upper shaft support hole 6, and the lower shaft support hole 8 from the front to the rear of the caster. In the upper fork 1a, the buffer member 9 is arranged in a lateral direction so as to be extendable and contracted, and the shaft is supported by the shaft support hole 5 at the lower part of the upper fork 1a and the shaft support hole 7 at the middle part of the lower fork 1b. 10, the upper fork 1 a and the lower fork 1 b can be rotated, and the wheel 12 is pivotally supported by the axle 11 in the lower shaft support hole 8 of the lower fork 1 b.
[0011]
In the upper fork 1a, side plates 14 and 14 are suspended from both ends of the upper plate 13 by bending a metal plate or the like.
[0012]
The lower fork 1b is made of side plates 15 and 15 made of metal plates disposed inside the side plates 14 and 14 of the upper fork 1a. 15 and 15 can be maintained.
[0013]
The buffer member 9 includes a cylindrical body portion 17a of a coil spring 17 encapsulated by a vibration isolator 18 having rubber-like elasticity, and the front and rear ends of the buffer member 9 are supported by front and rear support members 19 and 20, respectively. The front support 19 is pivotally supported in the upper support hole 4 of the upper fork 1a, and the rear support 20 is supported in the upper support hole 6 of the lower fork 1b so that it can expand and contract in the upper fork 1a. It is assumed that it is arranged in the horizontal direction for free. In order to make the cylindrical body portion 17a of the coil spring 17 encapsulated by the vibration isolator 18, for example, a mold is disposed around the inside and outside of the cylindrical body 17a, and raw rubber is put into the mold frame. What is necessary is just to form by adding pressure.
[0014]
Further, the buffer member 9 loosely penetrates the support pin 21 in the cylindrical body portion 17 a of the coil spring 17, and the front end of the support pin 21 is pivotally supported by the front support 19 and the rear end is pivotally supported by the rear support 20. It is supposed to be. By doing so, the buffer member 9 is supported in a stable state by the front and rear supports 19 and 20. The front and rear supports 19 and 20 are each substantially U-shaped. The front end of the buffer member 9 is surrounded by the front support 19 and the rear end of the buffer member 9 is surrounded by the rear support 20. 9 is protected, but the shapes of the front and rear supports 19 and 20 are not particularly limited.
[0015]
In the caster of the present invention, the degree of elasticity of the coil spring 17 of the cushioning member 9 depends on the cushioning effect required depending on the degree of unevenness or stepped portion on the road or the like. That is, when the caster of the present invention is used in a few uneven portions or stepped portions and a large cushioning effect is not required, the elastic modulus is increased, and conversely when used in large uneven portions or stepped portions, the elastic modulus is increased. Should be reduced.
[0016]
The caster of the present invention configured as described above is attached to the bottom of transport equipment and various transport vehicles, and when traveling on uneven parts such as roads or oversteps, the buffer member is as follows. Act on.
[0017]
First, when the wheel 12 of the caster of the present invention hits an uneven part or a step part of a road or the like, the wheel 12 is lifted from the state shown in FIG. 10, and the axle 12 moves upward so that the lower fork 1b is moved to the arrow A. Rotate in the direction, and the state shown in FIG. 12 is obtained, and the wheel 12 rides on the uneven part or the step part. At this time, when the coil spring 17 of the buffer member 9 is contracted, the impact acting on the wheel 12 is absorbed. Further, the impact sound emitted from the coil spring 17 when this impact is absorbed is absorbed by the vibration isolator 18. After the wheel 12 rides on the uneven portion or step portion, the reduced coil spring 17 of the buffer member 9 returns to its original state by the restoring force, and the lower fork 1b also rotates in the direction opposite to the arrow A direction. Then, the vehicle returns to the original state and can maintain a normal traveling state.
[0018]
Further, when the wheel 12 of the caster of the present invention hits an uneven part or a step part such as a road, the shock acting on the wheel 12 is absorbed by the coil spring 17 of the buffer member 9 being reduced as described above. In this case, the time until the vibration isolator 18 encapsulating the cylindrical body portion 17a of the coil spring 17 is reduced and returned to the original is delayed from the time until the coil spring 17 is reduced and returned to the original. Vibration is relieved by the delay, and the running state of the caster becomes smooth.
[0019]
Further, even when the wheel 12 of the caster of the present invention hits an uneven part or step part of a road or the like and the coil spring 17 resonates, the vibration is prevented by the vibration isolator 18 and the vibration during the caster traveling can be reduced. .
[0020]
【The invention's effect】
Since the caster of the present invention is configured as described above, the caster is not bulky, and noise such as a squeak noise is generated even when traveling on uneven parts such as roads or overstepped parts. It was not generated, the vibration was reduced, the resonance of the coil spring was suppressed, the vibration was reduced, and smooth running was achieved.
[Brief description of the drawings]
FIG. 1 is a side view of a caster according to the present invention.
FIG. 2 is a front view of a caster according to the present invention.
FIG. 3 is a cross-sectional view of a caster according to the present invention.
4 is a cross-sectional view taken along line AA in FIG.
FIG. 5 is a partial cross-sectional side view of an upper fork of a caster according to the present invention.
FIG. 6 is a front view of an upper fork of a caster according to the present invention.
FIG. 7 is a side view of a lower fork of a caster according to the present invention.
FIG. 8 is a front view of a lower fork of a caster according to the present invention.
FIG. 9 is a half sectional view of the buffer member of the caster according to the present invention.
FIG. 10 is a partial cross-sectional side view showing a state immediately before the buffer member of the caster according to the present invention operates.
FIG. 11 is a partial cross-sectional plan view showing a state immediately before the buffer member of the caster of the present invention acts.
FIG. 12 is a partial cross-sectional side view showing a state in which the buffer member of the caster according to the present invention acts.
FIG. 13 is a partial cross-sectional plan view showing a state in which the buffer member of the caster according to the present invention has acted.
FIG. 14 is a side view of a conventional caster.
FIG. 15 is a cross-sectional view of a conventional caster.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Fork 1a Upper fork 1b Lower fork 4 Shaft support hole 5 Shaft support hole 6 Shaft support hole 7 Shaft support hole 8 Shaft support hole 9 Buffer member 10 Shaft 11 Axle 12 Wheel 17 Coil spring 17a Cylindrical trunk 18 Vibration isolator 19 Front support 20 Rear support 21 Support pin

Claims (2)

The fork (1) is divided into an upper fork (1a) and a lower fork (1b), and the shaft support holes (4, 5) formed in the upper and lower parts of the upper fork (1a) are replaced with upper shaft support holes (4 ), The lower shaft support holes (5) are arranged in the order from the front to the rear of the caster, and the shaft support holes (6, 7, 8) formed in the upper, middle and lower portions of the lower fork (1b) It is assumed that the hole (7), the upper shaft support hole (6), and the lower shaft support hole (8) are arranged in this order from the front to the rear of the caster, and the cylindrical body (17a) of the coil spring (17) is provided. The front end of the buffer member (9) encapsulated by the vibration isolator (18) is surrounded by the front support (19), and the rear end of the buffer member (9) is surrounded by the rear support (20). The front and rear ends of the member (9) are supported by the front and rear supports (19, 20), respectively, and the front support (19 Together with journaling on top of the shaft supporting hole of the upper fork (1a) (4), by supported by a shaft supporting hole (6) of the top of the rear support (20) a lower fork (1b), an upper It is assumed that the buffer member (9) is disposed in the fork (1a) in a lateral direction so as to be expandable and contractible, and the lower shaft support hole (5) of the upper fork (1a) and the shaft support hole ( 7), the support shaft (10) is passed through to allow the upper fork (1a) and the lower fork (1b) to turn, and the axle (11) is inserted into the shaft support hole (8) at the lower portion of the lower fork (1b). ) To support the wheel (12).   A support pin (21) is allowed to freely pass through the cylindrical body (17a) of the coil spring (17). The caster according to claim 1, wherein the caster is pivotally supported on the caster.

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