JP6405229B2 - caster - Google Patents

Description

  The present invention relates to a caster used for facilitating movement of an installation such as furniture, furniture, a piano, and a copy machine, and more particularly to a caster having a seismic isolation function.

  Conventionally, it is attached to the bottom and legs of furniture, furniture, pianos, photocopiers, etc., and facilitates movement of the installation by rotating the wheel. 2. Description of the Related Art A caster with a stopper that can be locked to restrict movement of an installed object is known. For example, Patent Document 1 describes a twin-wheel caster with a stopper that can simultaneously stop and release rotation of a tire and turning of a caster head by a single depression operation of a stop pedal or a release pedal. According to this two-wheel caster with a stopper, when the installation object is moved, the release pedal is depressed to enable rotation of the tire and turning of the caster head, thereby facilitating movement of the installation object to which the caster is attached. After installation of the installation object, the movement of the installation object to which the caster is attached can be regulated by depressing the stop pedal to stop the rotation of the tire and the turning of the caster head.

JP2013-249001A

  In the conventional caster with a stopper, when the rotation of the wheel is locked and the movement of the installation is restricted, the following problems occur. That is, since the installation object is fixed to the installation site via the caster with a stopper, the shaking of the installation site due to an earthquake or the like is transmitted to the installation object via the caster with a stopper. For this reason, in furniture, furniture, etc., things such as tableware and exhibits may fall down or fall from furniture, furniture, etc. In addition, the installation itself could fall over due to a large shake.

  This invention is made | formed in view of the said situation, and it is providing the caster provided with the seismic isolation function.

  In order to solve the above problems, in the caster of the present invention, the length of the axle is made larger than the length in the axial direction of the axle holding hole of the wheel into which the axle is inserted, and the axial center At least two sliding regions for generating a frictional force different from the inner peripheral surface of the axle holding hole in the direction are provided. The wheel torque can be varied by moving the axle inserted into the axle holding hole in the axial direction of the axle and switching the sliding area of the axle that is in sliding contact with the inner peripheral surface of the axle holding hole. In addition, by attaching a stopper to the axle and restricting the movement of the axle in the axial direction, the axle is moved in the axial direction by vibration or the like, and the sliding area of the axle is in sliding contact with the inner peripheral surface of the axle holding hole. Can be prevented from switching unintentionally.

For example, the caster of the present invention is
A wheel having an axle retaining hole;
An axle having a length greater than the axial length of the axle holding hole, and being inserted into the axle holding hole to rotatably hold the wheel;
A stopper for restricting movement of the axle in the axial direction,
The outer peripheral surface of the axle is
Having at least two sliding regions for generating different frictional forces with the inner peripheral surface of the axle holding hole in the axial direction of the axle;
In a state where the restriction by the stopper is released, the sliding region that is in sliding contact with the inner peripheral surface of the axle holding hole can be switched by movement of the axle in the axial direction.

  According to the present invention, for example, when the installation object to which the caster according to the present invention is attached is moved, the axle is moved in the axial direction, and the outer peripheral surface of the axle that is in sliding contact with the inner peripheral surface of the axle holding hole is By switching the sliding area to one sliding area, a small frictional force is generated between the axle holding hole and the inner peripheral surface of the axle holding hole. In this state, a stopper is attached to the axle to restrict movement of the axle in the axial direction. This makes it possible to reduce the rotational torque of the wheels and facilitate the movement of the installation object. Further, during the movement of the installation object, the axle moves in the axial direction due to vibrations, etc. It is possible to prevent unintentional switching to the other sliding region that generates a frictional force larger than the frictional force between the inner peripheral surface of the first sliding region and the one sliding region. In addition, after the installation object to which the caster according to the present invention is attached is installed, the axle is moved in the axial direction, and the sliding region of the outer peripheral surface of the axle that is in sliding contact with the inner peripheral surface of the axle holding hole is made to slide on the other side. Switch to the region, generate a friction force larger than the friction force between the inner peripheral surface of the axle holding hole and one sliding region, and attach a stopper to the axle in this state to move the axle in the axial direction By restricting the wheel, the rotational torque of the wheel is increased so that the installed object does not easily move from the installation location, and the wheel rotates when torque exceeding this rotational torque is applied to the wheel. This can attenuate the vibration when the installation site shake due to an earthquake etc. is transmitted to the installation, and after installation, the axle moves in the axial direction due to vibration etc. Small friction with the peripheral surface It can be prevented from switching unintentionally to one of the sliding region for generating. Therefore, according to this invention, the caster provided with the seismic isolation function can be provided.

1A and 1B are a front view and a side view of a caster 1 according to an embodiment of the present invention, and FIG. 1C is a view of the caster 1 shown in FIG. It is AA sectional drawing. 2 (A) and 2 (B) are a front view and a rear view of the wheel 2, and FIG. 2 (C) is a cross-sectional view taken along the line BB of the wheel 2 shown in FIG. 2 (A). FIG. 3 is a front view of the axle 3. 4A is a side view of the collar 7, and FIG. 4B is a cross-sectional view taken along the line C-C of the collar 7 shown in FIG. 4A. 5A, 5B, and 5C are a front view, a side view, and a rear view of a modified example 7 'of the collar 7, respectively. FIG. 6 is a front view of a modification 3 ′ of the axle 3.

  Hereinafter, an embodiment of the present invention will be described.

  1 (A) and 1 (B) are a front view and a side view of caster 1 according to the present embodiment, and FIG. 1 (C) is an AA view of caster 1 shown in FIG. 1 (A). It is sectional drawing.

  As shown in the figure, a caster 1 according to the present embodiment includes a pair of wheels 2a and 2b (hereinafter also simply referred to as wheels 2), and a columnar axle 3 that rotatably holds these wheels 2a and 2b. A holding portion 4 that holds the axle 3 so as to be movable in the direction of the axis O and a stopper 5 for restricting movement of the axle 3 in the direction of the axis O are provided.

  The pair of wheels 2 a and 2 b are disposed so as to sandwich the holding portion 4 from both sides in the direction of the axis O, and are rotatably held by the axle 3.

  2 (A) and 2 (B) are a front view and a rear view of the wheel 2, and FIG. 2 (C) is a cross-sectional view taken along the line BB of the wheel 2 shown in FIG. 2 (A). As shown in the figure, the wheel 2 includes an annular wheel body 20 and a bearing bush 21 that is mounted on the inner peripheral surface 200 of the wheel body 20 and into which the axle 3 is inserted.

  FIG. 3 is a front view of the axle 3. As shown in the figure, threaded portions 31 a and 31 b that are screwed into nuts 6 a and 6 b (see FIG. 1) are formed at both end portions 30 a and 30 b of the axle 3. Here, the length L1 between the screw portions 31a and 31b formed at both end portions 30a and 30b of the axle 3 is three times as long as the thickness L2 in the axis O direction of the wheel 2 and the axis of the holding portion 4. The total value of the length L3 in the O direction is equal to or greater than (L1 ≧ 3 × L2 + L3).

  Further, on the outer peripheral surface 32 of the axle 3, the axle 3 is moved in the direction of the axis O (FIG. 1) until a nut 6 a screwed to a screw portion 31 a formed on one end 30 a of the axle 3 comes into contact with the wheel 2 a. Two first sliding surfaces 33 are formed which are in sliding contact with the inner peripheral surface 210 of the bearing bush 21 of each wheel 2a, 2b when moved in the + direction of (C), and the other side of the axle 3 When the axle 3 is moved in the direction of the axis O (the negative direction in FIG. 1C) until the nut 6b screwed into the threaded portion 31b formed on the end 31b of the wheel contacts the wheel 2b, Two second sliding surfaces 34 are formed in sliding contact with the inner peripheral surface 210 of the bearing bush 21 of 2a and 2b.

  The first sliding surface 33 and the second sliding surface 34 have different friction coefficients. For example, one of the first sliding surface 33 and the second sliding surface 34 is roughly processed by knurling, embossing, or the like, and the other is processed smoothly so that the first sliding surface 33 and the second sliding surface 34 are processed. By changing the surface roughness of the two, the friction coefficient of both is made different. Alternatively, one of the first sliding surface 33 and the second sliding surface 34 is coated with a material having excellent sliding characteristics such as fluorine, and the other of the first sliding surface 33 and the second sliding surface 34 is made of rubber or the like. By coating the material having the inferior sliding property and changing the materials of the first sliding surface 33 and the second sliding surface 347, the friction coefficients of both are made different. Alternatively, the friction coefficients of the first sliding surface 33 and the second sliding surface 34 are made different by combining them. In the present embodiment, the friction coefficient of the first sliding surface 33 is reduced and the friction coefficient of the second sliding surface 34 is increased.

  The holding part 4 includes a holding part main body 40 and an attachment part 41. The holding part main body 40 is disposed between the pair of wheels 2a and 2b, and has a through hole 42 for holding the axle 3 so as to be movable in the direction of the axis O. The attachment portion 41 is for attaching the caster 1 to the bottom surface, legs, etc. of an installation such as furniture, furniture, piano, copy machine or the like. Here, as the attachment portion 41, a screw that is screwed into a screw hole provided in a bottom surface, a leg portion, or the like of the installation object is provided. However, the mounting portion 41 can be changed as appropriate according to the mounting structure of the installation object. Moreover, you may make the holding | maintenance part main body 40 rotatable with respect to the attachment part 41 by attaching the attaching part 41 to the holding | maintenance part main body 40 via a bearing.

  The stopper 5 includes nuts 6 a and 6 b that are screwed with screw portions 31 a and 31 b formed at both end portions 30 a and 30 b of the axle 3, and a collar 7 that can be attached to the axle 3. The nuts 6a and 6b have at least an outer diameter r2 larger than the inner diameter r1 of the bearing bush 21 of the wheel 2, and are screwed into screw parts 31a and 31b formed at both ends 30a and 30b of the axle 3, thereby 3 is prevented from falling off the bearing bush 21 of the wheel 2. The collar 7 is attached to a protruding portion of the axle 3 from the wheel 2.

  4A is a side view of the collar 7, and FIG. 4B is a cross-sectional view taken along the line C-C of the collar 7 shown in FIG. 4A. As shown in the figure, the collar 7 is a cylindrical member that can be attached to the axle 3, and has an outer diameter r3 larger than the inner diameter r1 of the bearing bush 21 of the wheel 2 and an inner diameter r4 smaller than the outer diameter r2 of the nuts 6a and 6b. Further, the length L4 of the collar 7 is twice as long as the thickness L2 of the wheel 2 in the axial center O direction from the length L1 between the screw portions 31a, 31b formed at both ends 30a, 30b of the axle 3. It is set shorter by a predetermined margin than a value (L1− (2 × L2 + L3) obtained by subtracting the total value of the length L3 of the holding portion 4 in the direction of the axis O.

  When the installation object to which the caster 1 having the above configuration is attached is moved, the nut 6a is attached only to the screw portion 31a formed at one end portion 30a of the axle 3, and the screw formed at the other end portion 30b of the axle 3. In the state where the nut 6b is not attached to the portion 31b and the collar 7 is removed from the axle 3, the axle 3 is moved in the direction of the axis O (the + direction in FIG. 1C) until the nut 6a contacts the wheel 2a. Let Then, the collar 7 is attached to the protruding portion of the axle 3 from the wheel 2b, and the nut 6b is attached to the screw portion 31b formed on the other end 30b of the axle 3.

  As a result, the two first sliding surfaces 33 having a small coefficient of friction formed on the outer peripheral surface 32 of the axle 3 are brought into sliding contact with the inner peripheral surface 210 of the bearing bush 21 of the wheels 2a and 2b, respectively, and the rotational torque of the wheel 2 is increased. And the movement of the installation can be facilitated. Further, the movement of the axle 2 in the direction of the axis O is restricted by the collar 7 attached to the axle 3 so as to be interposed between the wheel 2b and the nut 6b. For this reason, during the movement of the installation object, the nut 6b attached to the screw portion 31b formed on the other end 31b of the axle 3 due to vibration or the like approaches the wheel 2b (in the minus direction in FIG. 1C). It is possible to prevent the axle 3 from moving and unintentionally switching the sliding surface of the axle 3 in sliding contact with the inner peripheral surface 210 of the bearing bush 21 of the wheels 2a, 2b to the sliding surface 34 having a large friction coefficient.

  Further, after installation of the installation to which the caster 1 having the above-described configuration is installed, the nut 6b is attached only to the screw portion 31b formed on the other end 30b of the axle 3, and formed on the one end 30a of the axle 3. In the state where the nut 6a is not attached to the threaded portion 31a and the collar 7 is removed from the axle 3, the axle 3 is moved in the direction of the axis O (the minus direction in FIG. 1C) until the nut 6b contacts the wheel 2b. ). Then, the collar 7 is attached to the protruding portion of the axle 3 from the wheel 2a, and the nut 6a is attached to the screw portion 31a formed at one end 30a of the axle 3.

  As a result, the two second sliding surfaces 34 having a large friction coefficient formed on the outer peripheral surface 32 of the axle 3 are in sliding contact with the inner peripheral surface 210 of the bearing bush 21 of the wheels 2a and 2b, respectively, and the rotational torque of the wheel 2 is increased. It is possible to prevent this installation from moving easily from the installation location, and when the wheel 2 is applied with a torque greater than this rotational torque, the wheel 2 rotates, so that installation due to an earthquake, etc. This vibration can be attenuated when the vibration of the place is transmitted to the installation. Further, movement of the axle 2 in the direction of the axis O is restricted by the collar 7 attached to the axle 3 so as to be interposed between the wheel 2a and the nut 6a. For this reason, the axle 3 moves in a direction in which the nut 6a attached to the screw portion 31a formed at one end 31a of the axle 3 approaches the wheel 2a (the + direction in FIG. 1C) due to earthquake vibration or the like. Thus, the sliding surface of the axle 3 that is in sliding contact with the inner peripheral surface 210 of the bearing bush 21 of the wheels 2a and 2b can be prevented from unintentionally switching to the sliding surface 33 having a small friction coefficient.

  Thus, according to this Embodiment, the caster 1 provided with the seismic isolation function can be provided.

  In addition, this invention is not limited to said embodiment, Many deformation | transformation are possible within the range of the summary.

  For example, in the above-described embodiment, the stopper 5 having the nuts 6 a and 6 b that are screwed into the screw portions 31 a and 31 b formed at the both end portions 31 a and 31 b of the axle 3 and the collar 7 that can be attached to the axle 3. However, the present invention is not limited to this. The stopper 5 only needs to be able to regulate the movement of the axle 3 in the direction of the axis O as necessary.

  5A, 5B, and 5C are a front view, a side view, and a rear view of a modified example 7 'of the collar 7, respectively. As shown in the figure, the collar 7 ′ has a cylindrical collar body 70 and a pair of gripping portions 71 a and 71 b.

  The collar body 70 has an axial center of the wheel 2 from the outer diameter r3 larger than the inner diameter r1 of the bearing bush 21 of the wheel 2 and the length L1 between the screw parts 31a and 31b formed at both ends 30a and 30b of the axle 3. It is set shorter by a predetermined margin than a value (L1− (2 × L2 + L3)) obtained by subtracting the total value of twice the length L2 in the O direction and the length L3 of the holding portion 4 in the axis O direction. And a length L4. The collar body 70 has a slit 75 formed along the axis O from one end surface 72 a toward the other end surface 72 b and penetrating the outer peripheral surface 73 and the inner peripheral surface 74.

  The pair of gripping portions 71a and 71b are formed at positions where the slit 75 is sandwiched in the circumferential direction of the color main body 70, and are different from each other in the circumferential direction from the outer peripheral surface 71 of the color main body 70. Protrudes in the L direction).

  The collar 7 ′ having the above configuration can widen the gap g between the slits 75 by gripping the pair of gripping portions 71 a and 71 b and urging them in the direction in which they are approached. For this reason, the collar 7 ′ can be attached to and detached from the protruding portion from the wheel 2 of the axle 3 through the slit 75 whose gap g is widened by gripping the pair of gripping portions 71 a and 71 b. Therefore, the collar 7 ′ can be attached to and detached from the axle 3 without removing the nuts 6 a and 6 b from the axle 3, thereby improving workability.

  In this case, instead of the axle 3, as shown in FIG. 6, flange portions 35a and 35b having outer diameters r2 larger than the outer diameter r3 of the collar body 70 of the collar 7 ′ are formed at both end portions 30a and 30b. Another axle 3 'may be used. Further, if the collar 7 'can firmly hold the axle 3 like a clothespin and thereby can restrict the movement of the axle 3' in the axial direction, both end portions of the axle 3 'are provided. The flange portions 35a and 35b may not be formed.

  In the above embodiment, the bearing bush 21 is mounted on the inner peripheral surface 200 of the wheel body 20, and the inner peripheral surface 210 of the bearing bush 21 is formed on the outer peripheral surface 32 of the axle 3. 33 or the second sliding surface 34, but the present invention is not limited to this. The bearing bush 21 may be omitted, and the inner peripheral surface 200 of the wheel body 20 may be brought into sliding contact with the first sliding surface 33 or the second sliding surface 34 formed on the outer peripheral surface 32 of the axle 3.

  Further, in the above embodiment, the axle 3 in which the first sliding surface 33 and the second sliding surface 34 having different friction coefficients are arranged on the outer peripheral surface 32 along the axial direction is used. The invention is not limited to this. The axle 3 may be provided with an outer peripheral surface 32 having at least two sliding regions that generate different frictional forces with the inner peripheral surface 210 of the bearing bush 21 of the wheel 2 in the axial direction. For example, the clearance between one of the first sliding surface 33 and the second sliding surface 34 and the inner peripheral surface 210 of the bearing bush 21 of the wheel 2 is reduced, so that the first sliding surface 33 and the second sliding surface 34 The clearance between the other and the inner peripheral surface 210 of the bearing bush 21 of the wheel 2 is increased, and the first sliding surface 33 and the second sliding surface 34 and the inner peripheral surface 210 of the bearing bush 21 of the wheel 2 are increased. Different frictional forces may be generated between the inner peripheral surface 210 of the bearing bush 21 by changing the clearance. Alternatively, the outer peripheral surface 32 of the axle 3 is tapered in the axial direction, and the clearance between the outer peripheral surface 32 of the axle 3 and the inner peripheral surface 210 of the bearing bush 21 is made different depending on the position in the axial direction of the axle 3. Different frictional forces may be generated between the inner peripheral surface 210 of the bearing bush 21. Alternatively, a frictional force that differs between the inner peripheral surface 210 of the bearing bush 21 by disposing a smooth circular surface region and a wavy surface region in the axial direction on the outer peripheral surface 32 of the axle 3. May be generated.

  In the above-described embodiment, the description has been given by taking the twin-wheel type caster 1 having a pair of wheels 2 as an example. However, the present invention can also be applied to a single-wheel type caster having only one wheel 2. In this case, the length L1 between the screw portions 31a and 31b formed at both end portions 30a and 30b of the axle 3 is the thickness L2 of the wheel 2 in the axial center O direction and the length L3 of the holding portion 4 in the axial center O direction. (L1> L2 + L3), preferably twice the thickness L2 of the wheel 2 in the axis O direction and the length L3 of the holding portion 4 in the axis O direction. (L1 ≧ 2 × L2 + L3). Further, the length L4 of the collar 7 is determined from the length L1 between the screw portions 31a and 31b formed at both end portions 30a and 30b of the axle 3, and the thickness L2 of the wheel 2 in the axis O direction and the axis of the holding portion 4 It is only necessary to set a predetermined margin shorter than a value (L1− (L2 + L3)) obtained by subtracting the total value with the length L3 in the center O direction.

  1: Caster, 2, 2a, 2b: Wheel, 3, 3 ': Axle, 4: Holding part, 5: Stopper, 6a, 6b: Nut, 7, 7': Collar, 20: Wheel body, 21: Bearing bush 30a, 30b: end of axle 3, 31a, 31b: screw part, 32: outer peripheral surface of axle 3, 33: first sliding surface, 34: second sliding surface, 35a, 35b: flange portion, 40 : Holding part main body, 41: mounting part, 42: through hole of holding part main body 40, 70: collar main body, 71a, 71b: gripping part, 72a, 72b: end surface of collar 7 ', 73: outer peripheral surface of color main body 70 74: an inner peripheral surface of the collar body 70, 75: a slit, 200: an inner peripheral surface of the wheel body 20, 210: an inner peripheral surface of the bearing bush 21

Claims (9)

A wheel having an axle retaining hole;
An axle having a length greater than the axial length of the axle holding hole, and being inserted into the axle holding hole to rotatably hold the wheel;
A stopper for restricting movement of the axle in the axial direction,
The outer peripheral surface of the axle is
Having at least two sliding regions for generating different frictional forces with the inner peripheral surface of the axle holding hole in the axial direction of the axle;
The caster is capable of switching the sliding region in sliding contact with the inner peripheral surface of the axle holding hole by moving the axle in the axial direction in a state where the restriction by the stopper is released. . The caster according to claim 1,
The axle has screw portions formed at both ends,
The stopper is
A collar having an outer diameter larger than the diameter of the axle holding hole, and being attachable to a protruding portion of the axle in the axial direction from the axle holding hole;
A nut that is screwed into a threaded portion of the axle and prevents the collar attached to a protruding portion in the axial direction from the axle holding hole of the axle from falling off the axle. Caster to do. The caster according to claim 1,
The axle has flange portions formed at both ends,
The stopper is
A collar having an outer diameter larger than the diameter of the axle holding hole and an inner diameter smaller than the outer diameter of the flange portion, and a slit formed from one end surface toward the other end surface and penetrating the outer peripheral surface and the inner peripheral surface; ,
Gap adjusting means for adjusting an interval between the slits of the collar,
The color is
The caster, wherein the axle is attached to and detached from the protruding portion from the axle holding hole through the slit in a state where the gap between the slits is widened by the gap adjusting means. The caster according to claim 3,
The gap adjusting means includes
The collar has a pair of gripping portions that are formed at positions sandwiching the slit in the circumferential direction of the collar and project in different circumferential directions from the outer peripheral surface of the collar. A caster characterized in that the gap between the slits is widened by being biased in the direction. The caster according to any one of claims 1 to 4,
Each of the at least two sliding regions has a different surface roughness on the outer peripheral surface of the axle. The caster according to any one of claims 1 to 5,
Each of the at least two sliding regions has a different clearance between the outer peripheral surface of the axle and the inner peripheral surface of the axle holding hole. The caster according to any one of claims 1 to 6,
The casters according to claim 1, wherein the at least two sliding regions are made of different materials for the outer peripheral surface of the axle. The caster according to any one of claims 1 to 7,
The wheel is
An annular wheel body;
Bearing bush mounted on the wheel body,
The caster, wherein the axle holding hole is provided in the bearing bush. The caster according to any one of claims 1 to 8,
Holding means for holding the axle movably in the axial direction of the axle;
The wheel is
One each arranged on both sides in the axial direction of the axle of the holding means,
The axle is
A caster having a length equal to or greater than a total value of three times the axial length of the axle holding hole of the wheel and the axial length of the axle of the holding means. .

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