JP7141887B2 - caster - Google Patents

Description

Article 30, Paragraph 2 of the Patent Law applied Presented at the exhibition Exhibition date June 20, 2018 to June 22, 2018 Exhibition name The 22nd Mechanical Element Technology Exhibition Venue Tokyo Big Sight (Koto-ku, Tokyo) Ariake 3-11-1)

The present invention relates to casters.

Japanese Patent No. 3799554 (Patent Document 1) discloses a caster. This caster contains a conical coil spring inside. This conical coil spring absorbs the impact that occurs when the caster rides over a step. According to this caster, since the conical coil spring functions as a cushioning member, it is possible to absorb the impact that occurs when the caster climbs over a step (see Patent Document 1).

Japanese Patent No. 3799554

In the caster disclosed in Patent Document 1, for example, a large number of parts are used for attaching the conical coil spring, etc., so the number of parts is large. As a result, component costs are increasing.

The present invention has been made to solve such problems, and its object is to reduce the number of parts in a caster configured to absorb impact.

A caster according to the present invention comprises a first fork, a second fork, a wheel and a kick spring. The second fork is rotatably attached to the first fork and configured to contact the first fork at a predetermined position. A wheel is rotatably attached to the second fork. A kick spring is configured to bias the second fork toward a predetermined position.

In this caster, the impact is absorbed by the kick spring. No special parts are required to install the kick spring. Therefore, according to this caster, it is possible to reduce the number of parts as compared with a caster that requires special parts for attachment of a spring or the like.

Preferably, in the caster according to the present invention, the center of the kick spring is located below the upper end of the wheel.

According to this caster, the length in the height direction of the caster can be made shorter.

Further, preferably, the second fork includes a first plate portion and a second plate portion facing the first plate portion, the wheel is sandwiched between the first and second plate portions, and the caster is: Further provided is a first rod-shaped member that penetrates through the first and second plate portions and connects the first and second plate portions, and the kick spring is in contact with the first rod-shaped member.

In this caster, the first rod-shaped member is shared by the member that connects the first and second plate portions in the second fork and the member that supports the kick spring. Therefore, according to this caster, since it is not necessary to separately provide a member for connecting the first and second plate portions and a member for supporting the kick spring, the number of parts can be reduced.

Also preferably, the first fork includes a third plate portion and a fourth plate portion facing the third plate portion, and the caster extends through the first, second, third and fourth plate portions. , the first, second, third and fourth plate portions are further provided, and the kick spring is wound around the second rod-shaped member.

Also, preferably, the first fork includes an engaging portion that engages with the kick spring.

According to the present invention, it is possible to reduce the number of parts in a caster configured to absorb impact.

It is a figure which shows the side surface of a caster. It is a figure which shows the front surface of a caster. FIG. 4 shows the front of the caster and shows hidden lines; It is a figure which shows the cross section of a pin. It is a figure for demonstrating the operation|movement of a caster. It is a figure which shows the modification of a caster.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The same or corresponding parts in the drawings are denoted by the same reference numerals, and the description thereof will not be repeated.

[1. Configuration of casters]
FIG. 1 is a side view of caster 10 according to the present embodiment. FIG. 2 is a diagram showing the front surface of the caster 10. As shown in FIG. FIG. 3 is a diagram showing the front surface of caster 10 and showing hidden lines. 1, 2 and 3, the direction of arrow U indicates above the caster 10, and the direction of arrow D indicates below the caster 10. As shown in FIG. The direction of arrow R indicates the right side of caster 10, and the direction of arrow L indicates the left side of caster 10. As shown in FIG. The arrow F direction indicates the front of the caster 10 and the arrow B direction indicates the rear of the caster 10 . The direction of each arrow is the same in other drawings.

Casters 10 are attached, for example, to the bottom of carts for carrying various products (tofu, cakes, etc.). For example, four casters 10 are attached to one truck. In the caster 10, a structural contrivance is adopted to absorb the impact that occurs when the caster 10 climbs over a step. The configuration of the caster 10 will be described below.

As shown in FIGS. 1, 2 and 3, the caster 10 includes a fixing member 400, forks 100 and 200, wheels 300 and kick springs 500. As shown in FIGS. The fixing member 400 is configured by, for example, a screw stem made of metal, and is attached to the bottom of the truck or the like.

The fork 100 is made of metal and attached to the fixed member 400 via bearings (not shown). Fork 100 is pivotable with respect to fixed member 400 . The fork 100 is formed by bending a metal plate or the like, and includes an upper plate portion and side plate portions 102 and 104 (FIG. 2). An engaging portion 110 (FIG. 3) is formed inside each of the side plate portions 102 and 104 . Each engaging portion 110 is a substantially L-shaped portion extending inward from each of the side plate portions 102 and 104 . A role of the engaging portion 110 will be described later.

The fork 200 is made of metal and arranged so as to sandwich the fork 100 from the outside. The fork 200 is formed by bending a metal plate or the like, and includes side plate portions 202 and 204 and a front plate portion 250 . Fork 200 is rotatably attached to fork 100 via support pin 220 and pin 210 . That is, each of the support pin 220 and the pin 210 penetrates the side plate portions 202, 204 (FIG. 2) and the side plate portions 102, 104 and connects the side plate portions 202, 204 and the side plate portions 102, 104 together.

Note that the support pin 220 includes a pin 224 and a support member 222 (FIG. 3). The support member 222 is a cylindrical member made of MC nylon, for example, and covers the pin 224 . Further, the support pin 220 is located forward of the front end of the wheel 300 and located lower than the upper end of the wheel 300 (FIG. 1).

The fork 200 is rotatable with respect to the fork 100 with the support pin 220 as an axis. A resin bush 223 (FIG. 3) is arranged between the forks 100 and 200 and around the pin 224 . Therefore, metal wear due to rotation of the fork 200 is suppressed. A groove (not shown) is formed in the fork 100 to guide the rotation of the pin 210 accompanying the rotation of the fork 200, and the pin 210 rotates along the groove when the fork 200 rotates. do.

A pin 230 is attached to the fork 200 . The pin 230 penetrates the side plate portion 202 and the side plate portion 204 and connects the side plate portion 202 and the side plate portion 204 . Each of the pins 230, 210 has a role of keeping the length between the side plate portions 202, 204 constant. Here, as a representative of pins 230 and 210, the detailed configuration of pin 230 will be described. The configuration of pin 210 is similar to that of pin 230 .

FIG. 4 is a diagram showing a cross section of the pin 230. As shown in FIG. As shown in FIG. 4, pin 230 includes stepped pin 232 , cylindrical member 234 and cap 233 . The cap 233 is attached to the tip of the stepped pin 232 , and the cylindrical member 234 covers the stepped pin 232 . The end of the stepped pin 232 to which the cap 233 is not attached is caulked.

The stepped pin 232 has a stepped portion at a position in contact with the side plate portion 204 . Therefore, the side plate portion 204 is fixed from both sides by the stepped portion of the stepped pin 232 and the cap 233 . If the cylindrical member 234 were not provided, the side plate portion 202 could move inward. Since the cylindrical member 234 is provided in the pin 230 , the side plate portion 202 is fixed from both sides by the crimped portion of the stepped pin 232 and the cylindrical member 234 . Therefore, according to the pin 230, the length between the side plate portions 202 and 204 can be kept constant.

Referring to FIGS. 1, 2 and 3 again, wheel 300 is sandwiched between side plate portions 202 and 204 and attached to fork 200 via axle 240 . Wheel 300 is rotatable with respect to fork 200 .

The kick spring 500 is a so-called double torsion spring and is wound around the support pin 220 (support member 222). That is, the center (coil center) of kick spring 500 is positioned forward of the front end of wheel 300 and lower than the upper end of wheel 300 (FIG. 1). That is, in caster 10, the length in the height direction is shorter than when the center of the spring is positioned higher than the upper end of wheel 300. As shown in FIG.

Also, the vicinity of one end of the kick spring 500 is engaged with the engaging portion 110, and the vicinity of the other end of the kick spring 500 is engaged with the pin 230 (FIG. 3). The kick spring 500 urges the fork 200 so that the front plate portion 250 comes into contact with the front end of the fork 100 when the caster 10 is not subjected to impact or the like. That is, the fork 200 is positioned at a predetermined position (the position where the front plate portion 250 is in contact with the front end of the fork 100) when no impact or the like is applied to the caster 10. As shown in FIG.

[2. Correspondence]
Caster 10 is an example of the "caster" of the present invention. The fork 100 is an example of the "first fork" of the present invention, and the fork 200 is an example of the "second fork" of the present invention. The wheel 300 is an example of the "wheel" of the present invention, and the kick spring 500 is an example of the "kick spring" of the present invention. The side plate portion 202 is an example of the "first plate portion" of the present invention, and the side plate portion 204 is an example of the "second plate portion" of the present invention. The pin 230 is an example of the "first rod-shaped member" of the present invention. The side plate portion 102 is an example of the "third plate portion" of the present invention, and the side plate portion 104 is an example of the "fourth plate portion" of the present invention. The support pin 220 is an example of the "second rod-shaped member" of the present invention. The engaging portion 110 is an example of the "engaging portion" of the present invention.

[3. Movement of caster]
5A and 5B are diagrams for explaining the operation of the caster 10. FIG. Referring to FIG. 5, when caster 10 hits a step, wheel 300 is lifted upward. By lifting the wheel 300 , the kick spring 500 bends inward and the fork 200 rotates with respect to the fork 100 . As a result, the front plate portion 250 (FIG. 2) is separated from the front end of the fork 100 and the impact is absorbed. After the caster 10 climbs over the step, the bent kick spring 500 returns to its original state, and the fork 200 also returns to a predetermined position (the position where the front plate portion 250 contacts the front end of the fork 100).

[4. feature]
As described above, in caster 10 according to the present embodiment, impact is absorbed by kick spring 500 . No special parts are required for mounting the kick spring 500 . Therefore, according to this caster 10, it is possible to reduce the number of parts compared to a caster that requires special parts for attachment of a spring or the like.

Further, in the caster 10, a pin 230 is used as a member for connecting the side plate portions 202 and 204 of the fork 200 and a member for supporting the kick spring 500 (FIG. 3). Therefore, according to the caster 10, it is not necessary to separately provide a member for connecting the side plate portions 202 and 204 and a member for supporting the kick spring 500, so that the number of parts can be reduced.

[5. Modification]
Although the embodiments have been described above, the present invention is not limited to the above embodiments, and various modifications are possible without departing from the scope of the invention. Modifications will be described below.

In the above-described embodiment, the fixing member 400 is configured by a stem screw. However, the fixing member 400 does not necessarily have to consist of stem screws. The fixing member 400 may be configured by, for example, an attachment plate.

FIG. 6 shows a modification of caster 10 according to the above embodiment. As shown in FIG. 6, caster 10A includes fixing member 400A. The fixing member 400A is a plate that can be attached to the bottom surface of the truck or the like. The fixing member 400A is, for example, screwed to the bottom surface of the truck. The fork 100 is rotatably attached to the fixed member 400A.

10,10A Caster 100,200 Fork 102,104,202,204 Side Plate Part 110 Engagement Part 210,224,230 Pin, 220 Support Pin, 222 Support Member, 223 Bush, 232 Stepped Pin, 233 Cap , 234 cylindrical member, 240 axle, 250 front plate portion, 300 wheel, 400, 400A fixing member, 500 kick spring.

Claims (4)

a first fork;
a second fork rotatably attached to the first fork and configured to contact the first fork at a predetermined position;
a wheel rotatably attached to the second fork;
a kick spring configured to bias the second fork toward the predetermined position;
The second fork is molded by bending a metal plate,
a first plate;
a second plate portion facing the first plate portion ;
a front plate portion that contacts the first fork at the predetermined position;
including
The wheel is sandwiched between the first and second plate portions,
The caster is
a first rod-shaped member penetrating through the first and second plate portions and connecting the first and second plate portions;
a movable rod-shaped member penetrating through the first and second plate portions and connecting the first and second plate portions;
further comprising
The kick spring is in contact with the first rod-shaped member,
The first fork is formed with a groove that guides the rotation of the movable rod-shaped member accompanying the rotation of the second fork.
caster. 2. The caster according to claim 1, wherein the center of said kick spring is located at a position lower than the upper end of said wheel. The first fork is
a third plate;
including a fourth plate portion facing the third plate portion,
The caster is
further comprising a second rod-shaped member penetrating through the first, second, third and fourth plate portions and connecting the first, second, third and fourth plate portions;
3. The caster according to claim 1, wherein said kick spring is wound around said second rod-like member. The caster according to any one of claims 1 to 3, wherein the first fork includes an engaging portion that engages with the kick spring.

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