JPH11169257A - Bearing device for chair leg part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily fit a bearing device to be fitted to a lower end part of a leg part of a chair in order to reduce friction, to the surface part of the leg part and make the device compact and low in cost while reducing surface pressure acting upon a floor face. SOLUTION: Four sets of energizing members 17, retainers 15 and spherical bodies 16 are integrated into a body part 12 of a body block 41, and the body part 12 and a blocking plate 42 of the body block 41 are fixed to the lower end face of a leg part 2 by two machine screws so as to fit the body block 41 to the side face of the lower end part of the leg part 3 of the chair through a pair of fitting parts 43 integrally rising from the blocking plate 42. In a non- seated state of the chair, the spherical bodies 16 are put in the protruding position, and in a seated state, the spherical bodies 16 are put in the receding position to bring the body block 41 into contact with a floor face 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing device for a chair leg, and more particularly to a device for reducing friction between a chair and a floor when not sitting on the chair. However, in this specification, the term "bearing device" is synonymous with the term "caster device".

2. Description of the Related Art In the case of a chair with four legs used in a dining room at home, there is no caster wheel, idle wheel or idle ball on the legs, so an empty chair is moved to the table side or vice versa. It is inconvenient when moving in the direction or when cleaning, the floor is easily damaged, and unpleasant friction noise is likely to be generated.

In view of this, various techniques have been proposed for mounting caster wheels or idle wheels on the legs of such chairs. For example, Japanese Utility Model Application Laid-Open No. 5-86255, Japanese Utility Model Application Laid-Open No. 6-3354.
No. 0 proposes a caster wheel for mounting on a chair leg or the like, and Japanese Utility Model Laid-Open No. 7-9145 discloses a caster wheel for mounting on a connecting member for connecting lower ends of chair legs. Japanese Patent Laid-Open Publication No. Hei 7-108014 proposes that an idler wheel attached to a connecting member that connects the lower ends of the legs of a chair and that is in a protruding position in a state where the chair is not seated and in a state where the seat is seated. Idler wheels have been proposed to be in a retracted position.

On the other hand, in the chair with a caster described in Japanese Utility Model Laid-Open Publication No. 7-27354, a housing hole is formed in a leg on the front side of the chair, and a freewheel type caster unit is attached to the housing hole. An accommodation hole is formed at the lower end of the rear leg, and a spherical caster unit is attached to this accommodation hole.If a person is not sitting on a chair, the idler wheel and the sphere are removed from the lower end surface of the leg. It is made to protrude partially.

In this spherical caster unit, a cylindrical case having an open bottom surface is fixed in a housing hole, and a spherical member is mounted in a lower part of the cylindrical case so as to be partially protrudable and vertically movable. Inside the case, a plurality of small spheres that contact the upper surface of the sphere, an elevating body that contacts the upper surface of the small sphere, and a spring that biases the sphere to the projecting side via the elevating body and the small sphere Is provided.

[0005]

Problems to be Solved by the Invention
255, JP-A-6-33540, JP-A-7
No. 9145, Japanese Unexamined Patent Publication No. 7-108014, etc.
When the idle wheel type caster unit disclosed in Japanese Patent No. 27354 is attached to the legs of an existing chair, it is necessary to modify the chair, it is difficult to easily attach the chair, the appearance of the chair may be impaired, There is a problem that there is a possibility that the height position of the seat portion is greatly changed, and that the size is large and the manufacturing cost is expensive.

The spherical caster unit disclosed in Japanese Utility Model Laid-Open Publication No. Hei 7-27354 is basically intended to be mounted on a chair leg by a chair maker, so that a user can retrofit it onto an existing wooden leg. Not suitable for mounting at If this spherical caster unit is to be attached to the leg of an existing chair, a hole with a circular cross section of about 2 cm depth must be formed in the leg, so a tool such as a drill is used to attach it. It takes a lot of effort. Since the load acting on each leg due to the chair's own weight is supported by one sphere, the contact pressure with the floor surface tends to increase, which is not preferable in terms of floor protection. Moreover, when a person sits on a chair and the sphere retreats into the cylindrical case, a large annular space is created between the sphere and the cylindrical case due to the large sphere, and dust entering the gap is removed by the sphere and the cylinder. It is easy to get caught between the lower ends of the cylindrical cases, and there is a possibility that the rotational performance of the sphere is reduced.

Since the size and cross-sectional shape of the legs of existing chairs are various, it is not easy to firmly attach a bearing device including an idle ball or the like to the lower end of the legs of the chair by retrofitting. In fact, such a conventional bearing device has not been proposed at all. The purpose of the present invention is
To provide a bearing device that can be attached to the surface of the lower end portion of an existing chair without modification, to enable easy installation of the bearing device, and to reduce the size and cost of the bearing device. And reducing the surface pressure of the contact portion between the bearing device and the floor.

[0008]

The chair leg bearing device according to claim 1 is a bearing device attachable to a surface of a lower end portion of a chair leg portion, wherein at least a lower end surface of the chair leg portion. And a plurality of spheres movably and rotatably mounted on the main body block to a protruding position partially protruding from a lower end surface of the main body block and a retreating position not protruding from the lower end surface of the main body block. And a plurality of biasing members for respectively elastically biasing the plurality of spheres toward the projecting position, wherein the plurality of spheres are in the projecting position against the load due to the weight of the chair, and in a state where a person is seated. A plurality of spheres are configured to be in the retreat position. Here, the lower end of the leg means the vicinity thereof including the lower end of the leg.

This bearing device reduces the friction between the legs of the chair and the floor surface when no person is seated, and the main body block is fixed to at least the lower end surface of the legs. In the state where a plurality of spheres are mounted, and in a state where a person does not sit on a chair, the plurality of spheres are elastically urged by a plurality of urging members, respectively, and project from a lower end surface of the main body block at a projecting position. And contact the floor to support the legs. Therefore, the chair can be moved lightly on the floor. When a person sits on the chair, the plurality of spheres come to the retreat position and are supported by the main body block, so that the stability of the chair can be secured and the plurality of spheres do not bite into the floor. Since this bearing device is intended to be mounted on the surface portion including the lower end surface of the leg portion of the chair, it can be easily mounted on the existing leg portion of the chair without any modification, and is excellent in versatility. .

In the invention according to claim 2, at least four spheres are provided. Therefore, a sphere having a diameter of about 5 to 10 mm is applied, and the main body block is made about 15 to 20 mm.
The height of the seat can be reduced to a small height.

According to the third aspect of the present invention, a retainer made of metal or synthetic resin for rotatably holding each sphere is provided in the accommodation hole of the main body block so as to be integrally movable with the sphere, and when the retainer is in the protruding position, the retainer is made of a metal. The lower end is configured to protrude from the lower end surface of the main body block. Therefore, no gap is formed between the sphere and the retainer, and the rotation performance of the sphere is not reduced due to accumulation of dust. Further, since at least the lower part of the accommodation hole is a cylindrical hole, even if dust enters the accommodation hole, the dust is pushed out by the retainer, so that durability and reliability can be secured.

According to the fourth aspect of the present invention, each biasing member comprises a plurality of disc springs. Therefore, in reducing the size of the biasing member,
Further, it is advantageous in strengthening the urging force. According to the fifth aspect of the present invention, a plurality of attachment portions are provided for fixing the main body block to the plurality of side surfaces of the lower end portion of the leg of the chair.
Therefore, the mounting strength for mounting the main body block can be sufficiently increased.

According to the sixth aspect of the present invention, the mounting portion is made of a soft synthetic resin material. Therefore, it is advantageous in that the mounting portion is brought into close contact with the side surfaces of the legs of various sizes and shapes. According to the seventh aspect of the present invention, the mounting portion is configured to be flexible in a direction approaching and separating from the side surface of the leg portion of the chair. Therefore, the same operation as that of the sixth aspect is achieved. According to the eighth aspect of the present invention, the mounting portion is formed of a metal plate. Therefore, it is advantageous in fixing the mounting portion to the side portion of the leg with a screw,
It is also advantageous in increasing the strength of the mounting part.

According to the ninth aspect of the present invention, a buffer layer made of a soft synthetic resin material is provided on at least an upper end portion of the main body block. Therefore, it is advantageous in that the main body block is fixed to the lower end surface of the leg portion in close contact with the lower end surface, and the sitting comfort when a person sits on the chair is improved, and the impact acting on the main body block can be absorbed. According to the tenth aspect of the present invention, a buffer layer made of a soft synthetic resin material is provided on at least an upper end portion of the main body block, and the buffer layer and a plurality of flexible mounting portions are integrally formed. The buffer layer has the same function as the ninth aspect. Since the buffer layer and the plurality of flexible attachment portions are integrally formed, the bonding strength between the main body block and the plurality of attachment portions can be secured.

According to the eleventh aspect of the present invention, the main body block is
Or, it is fixed to the lower end surface of the chair by a plurality of screws. Therefore, the main body block can be strongly and easily fixed to the lower end surface of the chair. According to the twelfth aspect of the invention, the main body block is fixed to the lower end surface of the leg of the chair using an adhesive or an adhesive. Therefore, the main body block can be fixed without damaging the leg of the chair with the screw. Further, when the fixing is performed using both the adhesive or the adhesive and the screw, the main body block can be firmly fixed to the lower end surface of the leg.

According to the thirteenth aspect, the mounting portion is fixed to the side portion by one or more screws. for that reason,
The mounting part can be strongly and easily fixed to the side part of the leg. In particular, it is suitable for the case where the mounting portion is made of a metal plate. In the fourteenth aspect, the mounting portion is fixed to the side portion using an adhesive or a pressure-sensitive adhesive. Therefore, it is possible to fix the mounting portion to the side surface of the leg without damaging the leg with the screw. Further, in the case of fixing using both the adhesive or the adhesive and the screw, the mounting portion can be firmly fixed to the side surface of the leg.

According to the fifteenth aspect, the mounting portion is made of a transparent or substantially transparent material. Therefore, it is advantageous in maintaining the appearance of the side surface of the leg.

[0018] The bearing device according to the present invention is a bearing device which can be attached to a surface of a lower end portion of a leg of a chair, wherein the load acting on the leg of the chair can be transmitted to a floor surface. A main body block fixed to a lower end of the main body block, and a movable position and a rotatable mounted to the main body block so as to be movable to a protruding position partially protruding from a lower end surface of the main body block and a retreating position not protruding from the lower end surface. Multiple spheres,
A plurality of biasing members for elastically biasing the plurality of spheres toward the protruding position, wherein a plurality of spheres are in a protruding position against a load due to the weight of the chair, and a plurality of spheres are in a state where a person is seated. The sphere is configured to be in the retracted position. In this bearing device, since the main body block may be fixed to the lower end of the leg so that the load acting on the leg can be transmitted to the floor, the main body block may be fixed to the lower end of the leg. However, it is not always necessary to fix the main body block to the lower end face, as long as the main body block is fixed to the lower end of the leg. Other configurations are the same as those of the first aspect, and thus basically provide the same operation as that of the first aspect.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIGS.
Bearing devices 10 are fixed to the lower end portions of the four wooden legs 2 of the chair 1, respectively.
The chair is supported on the floor surface 3 via 0. Each bearing device 10 can be attached to the surface of the lower end of the leg portion 2 and can be purchased by a user and attached to the existing chair 1. The bearing device 10 includes a main body block 11, four receiving holes 14, and four retainers 15 respectively mounted below the four receiving holes 14.
And four spheres 16 rotatably held by the four retainers 15, four sets of urging members 17 for elastically urging the four spheres 16 downward, respectively, and the main body block 11 of the chair 1. Two screws 1 fixed to the lower end surface of the leg 2
8 and two screw holes 19 and the like.

The main body block 11 comprises a main body 12 made of a synthetic resin and a buffer layer 13 made of a soft synthetic resin constituting the upper end of the main body 12. The buffer layer 13 is provided on the upper end surface of the main body 12. It is fixed with an adhesive or a plurality of screws. The main body 12 is made of a hard and durable synthetic resin material, but may be made of a metal material. The buffer layer 13 is made of a soft synthetic resin material. Since the average size of the shorter side of the leg 2 of the ordinary chair 1 is about 25 to 30 mm, the size of the main body block 11 in plan view is about 30 mm × 30 mm in the case of the bearing device 10 of the present embodiment. It is.
However, since the main body block 11 may be smaller or larger than the size of the lower end surface of the leg portion 2, it is not limited to the above-described size, and the shape in plan view is not limited to the illustrated shape. Various shapes such as a circle are applicable.

The main body 12 has four vertical accommodation holes 1.
4 is formed in a penetrating manner, and the accommodation hole 14 has a large-diameter hole 20 for accommodating the urging member 17, and a small-diameter hole 21 connected to the lower end of the large-diameter hole 20 to hold the retainer 15 and the sphere 16 movably up and down. Consists of Both the large diameter hole 20 and the small diameter hole 21 are circular holes in cross section. The retainer 15 is formed by forming a thin metal plate (for example, a stainless steel plate) having a thickness of about 0.2 to 0.3 mm. The retainer 15 has an annular holding portion 22 for rotatably holding the spherical body 16 and an annular upper end. The sphere 16 is held by the holding part 22 so as to partially protrude downward from the lower end of the holding part 22. The holding portion 22 holding the sphere 16 is mounted in the small-diameter hole 21 so as to be vertically movable,
The flange portion 23 is locked at the annular step at the lower end of the large-diameter hole 20 so that it does not fall out.

In this embodiment, the sphere 16 has a diameter of about 6.0.
The size of the sphere 16 is not limited to this size, but may be a hard synthetic resin sphere. Each of the urging members 17 is formed by stacking, for example, seven disc springs.
The retainer 15 and the sphere 16 are urged by the urging member 17 toward the projecting position shown in FIGS. The four sets of retainers 15 and the spheres 16 are held at the protruding positions against the load caused by the weight of the chair 1. When a person sits on chair 1, four sets of retainers 15 and spheres 16
Is a retracted position that does not protrude from the lower end of the main body 12.
In the retracted position, the floor 3 is at the position shown by the chain line in FIG. 5, and the load acting on the leg 2 is supported by the main body block 11.

Since the weight of the chair 1 is about 3 to 5 kg, the load acting on each leg 2 due to this weight is about 75 kg.
0 g to 1200 g, and this load is supported by the four sets of urging members 17, so that the urging force of each urging member 17 is at least about 200 to
It may be 300gf. Therefore, as each urging member 17,
For example, it is desirable to use one that generates a biasing force of about 300 to 500 gf, but it is not limited to this.
However, as each urging member 17, any one of a compression coil spring, a leaf spring, a columnar body made of synthetic rubber, or the like may be used instead of the disc spring. When the urging force of each urging member 17 is set to be excessive, when a person sits down,
Since the floor 6 is not retreated, the floor 3 is easily damaged.

In the vicinity of the center of the main body block 11, 2
The two screw holes 19 are formed vertically. When the bearing device 10 is fixed to the lower end surface of the leg 2 of the chair 1, as shown in FIG. 5, the main body block 11 is brought into contact with the lower end surface of the leg 2, and two screws 18 are connected to two screws. It can be easily fixed by screwing into the legs 2 from the holes 19 respectively. However, an adhesive or pressure-sensitive adhesive layer is formed on the upper end surface of the main body block 11, a release paper is adhered to the surface of the layer, the release paper is peeled off, and the main body block 11 is legged with the adhesive or the pressure-sensitive adhesive. It may be configured to be fixed to the lower end surface of the portion 2 and then fixed with two screws 18. in this case,
If necessary, the main body block 11 may be fixed to the leg 2 only with an adhesive or a pressure-sensitive adhesive. However, body block 1
At the time of mounting 1, an adhesive or a pressure-sensitive adhesive may be applied and fixed to the upper end surface of the main body block 11 or the lower end surface of the leg 2.

The operation and effect of the bearing device 10 will be described. Since the bearing device 10 is configured to be fixed to the lower end surface of the leg portion 2 of the chair 1, it can be easily attached to the leg portion 2 of the existing chair 1 without any modification. Chair 1 total 1 when no person is seated
Since the chair 1 is supported on the floor 3 via the six rotatable spheres 16, the chair 1 is placed on the floor 3 with a slight force while being placed on the floor 3.
Can be moved, which is convenient for sitting down, leaving the room, cleaning, and the like.

Since four spheres 16 are provided for each bearing device 10, a small and inexpensive bearing device 10 having a small height can be obtained by applying a small sphere 16. Since it is a small bearing device, it is also advantageous in terms of the appearance of the chair. Since the four spheres 16 are provided, the surface pressure between the sphere 16 and the floor 3 becomes smaller as compared with the case where one sphere is provided. In a state where the person is seated, the four spheres 16 and the retainer 15 are at the retracted position, and the main body block 11 abuts on the floor surface 3, so that the floor surface 3 is not likely to be damaged by the sphere 16 and stability in the seated state This is also advantageous. However, it is desirable to provide four or more sets of the sphere 16, the retainer 15, and the urging member 17 in the bearing device 10, but it is also possible to provide three sets.

When four or more spheres 16 are provided, 6.0
By applying a sphere 16 having a diameter of about 8.0 mm, the main body block 11 can be configured to have a height of about 15 to 20 mm,
The increase in the height of the seat surface of the chair 1 can be kept small, and the surface pressure between the sphere 16 and the floor surface 3 can be kept sufficiently low, which is advantageous. It is also advantageous in terms of aspects. Since the buffer layer 13 made of a soft synthetic resin is provided at the upper end of the main body block 11, the main body block 11 is easily brought into close contact with the lower end surface of the leg 2 and is easily fixed. It is also preferable in terms of protection, and the sitting comfort is improved.
1 can be easily absorbed.

Each of the spheres 16 is held by a metal retainer 15 so that there is almost no gap between the lower end of the retainer 15 and the sphere 16 so that the retainer 15 and the sphere 16 are integrally retracted. Since it is configured, the sphere 16 and the retainer 15
Dust does not enter between, and the rotational performance of the sphere 16 does not decrease due to the dust. Since the lower portion of the housing hole 14 is formed as a cylindrical hole, even if dust enters the lower portion of the housing hole 14, the dust is pushed out by the retainer 15, so that durability and reliability can be secured. In addition, since the sphere 16 is moved to the projecting position together with the retainer 15, when the sphere 16 is in the projecting position, the distance between the lower end surface of the main body block 11 and the floor 3 can be increased, and the influence of unevenness of the floor 3 can be obtained. It is less susceptible to dust and is advantageous in terms of dust protection.

When the retainer 15 is made of metal, the holding performance for holding the sphere 16 and the durability can be improved. However, the retainer 15 may be made of a synthetic resin material having excellent hardness and strength. Since each urging member 17 is formed of a laminated body of seven disc springs, the urging member 17 can be downsized, and the urging force can be easily strengthened. However, the number of disc springs is not limited to seven. When the main body block 11 is fixed to the leg 2 using a plurality of screws 18, the bearing device 10
Mounting strength can be increased. However, the number of screws 18 is not limited to two.

As a modification in which the bearing device 10 is partially changed, as shown in FIG. 6, in this bearing device 30, the retainer 15 is omitted. That is, the lower part of the small-diameter hole 32 of the receiving hole 31 is formed in a partially spherical shape for holding the spherical body 16 so as not to come out, and the spherical body 16 is rotatably held in the small-diameter hole 32 in a partially protruding state. Have been. In the case of this structure, it is desirable that the main body portion 12 of the main body block 11 be made of a synthetic resin material or a metal material having excellent hardness and strength. In addition, the same components as those of the bearing device 10 are denoted by the same reference numerals, and description thereof is omitted.

Next, a plurality of other embodiments of the bearing device will be described. Another Embodiment 1 (see FIGS. 7 and 8) As shown in FIGS. 7 and 8, in the bearing device 40, the buffer layer 13 is omitted, and the main body block 41 is provided.
The upper end face of the main body 12 has a thickness of, for example, about 0.4 to 0.6 m.
A sealing plate 42 made of a metal plate of about m is fixed with an adhesive or a plurality of screws, and each urging member 17 is mounted in a compressed state. Two rectangular mounting portions 43 are formed, each of which rises integrally from two adjacent sides of the sealing plate 42, and each mounting portion 43 has, for example, two screw holes 44. The body block 41 has the same 2 as the screw hole 19.
Three screw holes are formed. The main body block 41 is fixed to the lower end surface of the leg 2 of the chair 1 with two screws as in the above embodiment. However, the main body block 41 may be fixed to the lower end surface of the leg portion 2 by a method similar to that of the above embodiment.

The two mounting portions 43 are preferably fixed to two adjacent side portions of the side portions of the leg portion 2 of the chair 1 which are opposed to the adjacent leg portions by two screws 45, respectively. You. However, an adhesive or a pressure-sensitive adhesive may be used in combination, and a layer of the adhesive or the pressure-sensitive adhesive and a release paper covering the surface thereof may be provided on the inner surface of the mounting portion 43, and the layer of the adhesive or the pressure-sensitive adhesive may be provided. It may be made to adhere with. In addition, the same components as those of the bearing device 10 are denoted by the same reference numerals, and description thereof is omitted.

In the case of this bearing device 40, even if the size of the leg 2 of the chair 1 is various, the two
Since the two mounting portions 43 can be securely fixed to one side portion, the bearing device 40 can be
The two screws can be firmly fixed to the leg 2.
The leg 2 of the chair 1 can be mounted even when the cross-sectional shape is not rectangular, and the mounting portion 43 can be deformed along the side surface of the leg 2 as needed. Other operations and effects are basically the same as those of the above embodiment.

Another Embodiment 2 (see FIGS. 9 to 13) As shown in FIGS. 9 to 11, in this bearing device 50, a buffer layer 52 and four flexible mounting portions 53 are formed. The buffer layer 52 is integrally formed using a durable transparent soft synthetic resin material, and the buffer layer 52 is fixed to the upper end surface of the main body 12 of the main body block 51 by bonding or by a plurality of screws. An adhesive or pressure-sensitive adhesive layer 54 is provided on the upper surfaces of the buffer layer 52 and the four attachment portions 53, and the surface of this layer 54 is covered with a release paper 55. As shown in FIG. 12, a notch 56 is formed in the outer peripheral portion of the buffer layer 52 so as to be easily attached to the small leg portion 2 of the chair 1. However, the cut 56 is not essential.

The thickness of the buffer layer 52 is, for example, about 3 to 5 mm, and the thickness of the mounting portion 53 is, for example, about 1.5 to 3.0 mm, and each extends from four sides of the buffer layer 52 in a direction parallel to the buffer layer 52. Four attachment portions 53 are formed. When attaching the bearing device 50 to the surface portion including the lower end surface of the leg portion 2 of the chair 1, the release paper 55 is peeled off, and the main body block 51 is attached to the lower end surface of the leg portion 2 with an adhesive or pressure-sensitive adhesive layer 54.
, And fixed with two screws similarly to the main body block 11. Next, each mounting portion 53 is strongly fixed to the corresponding side surface of the leg portion 2 by a layer 54 of an adhesive or a pressure-sensitive adhesive. FIG. 12 shows a state in which the bearing device 50 is fixed to the small leg 2, and each mounting portion 53 is attached to the leg 2.
Can be fixed in close contact with the side surface of the main body.

FIG. 13 shows a state in which the bearing device 50 is fixed to the leg 2 having a cross section larger than the main body block 51. In this case as well, each mounting portion 53 is fixed to the side surface of the leg 2 in close contact. be able to. The bearing device 50
After fixing to the leg portion 2, the four mounting portions 53 and the outer peripheral portion of the leg portion 2 can be tied up with a belt-shaped synthetic resin or metal fastener to further firmly fix them. The part 53 can be further firmly fixed by using a plurality of screws in combination. In addition, the bearing device 1
The same reference numerals are given to the same components as 0, and the description is omitted.

In this bearing device 50, the main body block 51 is fixed to the lower end surface of the leg 2, and the four mounting portions 53 are fixed to the four side surfaces of the leg 2. 2. The mounting strength for mounting on No. 2 can be sufficiently increased, and the durability and reliability are excellent. Since the four attachment portions 53 have flexibility, the small and large leg portions 2 and the leg portions having a cross-sectional shape other than a rectangular shape can be securely and firmly attached to the leg portions. In addition, since the adhesive or pressure-sensitive adhesive layer 54 and the release paper 55 are provided, the bearing device 50 can be easily attached to the leg 2.

Since the buffer layer 52 and the four mounting portions 53 are made of a transparent soft synthetic resin material, the degree of impairing the appearance of the leg 2 by the bearing device 50 can be reduced. However, the buffer layer 52 and the four attachment portions 53 may be made of an opaque soft synthetic resin material. Since the four mounting portions 53 are configured to be substantially parallel to the buffer layer 52, the bearing device 50 is compact in a product state, which is advantageous in terms of packaging, transportation, storage, and the like. Other operations and effects are basically the same as those of the above embodiment. As a modification of the bearing device 50, the thickness of the buffer layer 52 may be formed to be the same as the thickness of the mounting portion 53. In this case, the buffer layer 52 and the attachment portion 53 can be manufactured using a sheet material made of a soft synthetic resin.

Another Embodiment 3 (see FIGS. 14 to 16) As shown in FIGS. 14 to 16, this bearing device 60
In the above, the sealing plate 62 fixed to the upper end of the main body 12 of the main body block 61 and the four mounting portions 63 have a thickness of about
It is integrally formed of a bendable metal plate of about 0.4 to 0.6 mm. The four mounting portions 63 extend from four sides of the sealing plate 62 in a direction parallel to the sealing plate 62. Sealing plate 62
Is fixed to the upper end surface of the main body 12 with an adhesive or a plurality of screws, and for example, two screw holes 64 are formed in each mounting portion 63. An adhesive or pressure-sensitive adhesive layer 65 is provided on the upper surfaces of the sealing plate 62 and the four mounting portions 63.
Is covered with a release paper 66. In addition, the same reference numerals are given to the same components as those in the above-described embodiment, and the description is omitted.

The bearing device 60 is connected to the leg 2 of the chair 1.
When attaching to the surface portion including the lower end surface of the base, the release paper 66 is peeled off, and the main body block 61 including the main body portion 12 and the sealing plate 62 is fixed to the lower end surface of the leg portion 2 with an adhesive or pressure-sensitive adhesive layer 65. And insert it into the two screw holes 19
Secure with two screws. Next, each mounting portion 63 is bent along the corresponding side surface of the leg 2, and each mounting portion 63 is bent.
Are firmly fixed to the corresponding side portions by a layer 65 of an adhesive or a pressure-sensitive adhesive. However, if necessary, each mounting portion 63 may be fixed using two screws together by utilizing the screw holes 64.

In this bearing device 60, the main body block 61 is fixed to the lower end surface of the leg 2, and the four metal mounting portions 63 are fixed to the four side surfaces of the leg 2. Can be sufficiently increased in attaching to the leg portion 2, and the durability and reliability are excellent. In addition, since the four attachment portions 63 can be bent with a simple tool or hand, they can be firmly and securely attached to the small leg 2, the large leg 2, and the leg having a cross section other than a rectangular shape. Can be. In addition, since the adhesive or pressure-sensitive adhesive layer 65 and the release paper 66 are provided, the bearing device 60 can be easily attached to the leg 2. In addition, since the four mounting portions 64 are configured to be parallel to the sealing plate 62, the bearing device 60 is compact in a product state, which is advantageous in terms of packaging, transportation, storage, and the like. Other operations and effects are basically the same as those of the above embodiment.

Another Embodiment 4 (see FIGS. 17 and 18) This bearing device 70 is made of a metal plate case 71 which is fitted and fixed to the lower end of the leg of the chair. A main body block 72 fixed to the lower end surface of the main body block, and four sets of urging members 73, retainers 15, and spheres 16 mounted on the main body block 72. The main body block 72 is substantially the same as the main body (12) of the main body block of the embodiment. The case 71 has four side walls 71.
a and the bottom wall 71b are integrally formed and have a square shape in plan view, but the shape in plan view may be rectangular or circular, or may be various other shapes. The main body block 72 is made of metal or synthetic resin. The main body block 72 is fixed to the lower surface of the bottom wall 71b of the case 71 with an adhesive or a plurality of screws.

The main body block 72 and the bottom wall 71 of the case 71
b is fixed to the lower end surface of the leg 2 of the chair by using two screws so that the main body block 72 and the bottom wall 71b have
Two screw holes 74 are formed upright. However,
The main body block 72 and the bottom wall 71b of the case 71 do not necessarily need to be fixed to the lower end surface of the leg 2 of the chair, and are arranged so that the load acting on the leg 2 can be transmitted to the floor.
The four side walls 71a may be firmly fixed to the lower ends of the legs 2 as described later.

Four sets of receiving holes 14 (large-diameter hole 20 and small-diameter hole 2
1) and the structures of the retainer 15 and the spherical body 16 are the same as those of the above-described embodiment, and thus the same reference numerals are given and the description is omitted. The urging member 73 for urging each sphere 16 toward the protruding position is configured by a compression coil spring. However, similarly to the above-described embodiment, it may be constituted by a plurality of disc springs or synthetic rubber columns. Each ball 16 and a retainer 15 for rotatably holding the ball 16
A spring receiver 75 is provided on the upper side, and each of the urging members 73 urges the retainer 15 and the sphere 16 downward through the spring receiver 75.

As a structure for fixing the bearing device 70 to the lower end of the leg 2 of the chair, the lower end of the leg 2 is inserted into the case 71 so that the lower end surface of the leg 2 rests on the bottom wall 71b. The bearing device 70 is brought into contact with the gap between the side wall 71 a of the case 71 and the side surface of the leg 2 by fitting one or more plate-like spacers 76 or one or more wedge-like spacers 77. 2 can be easily and firmly fixed to the lower end. However, the case 71 may be additionally fixed to the side surface of the lower end of the leg 2 with a plurality of screws or adhesive.

The bearing device 70 basically functions in the same manner as the bearing device of the above-described embodiment, and four spheres 16 are formed as shown in FIG. 18 against the load caused by the weight of the chair. As a result, the main body block 72 floats from the floor 3. When the person is seated on the chair, the four spheres 16 are in the retracted position, and the lower surface of the main body block 72 is in contact with the floor 3 shown by the chain line. In this bearing device 70, it can be easily and firmly attached and fixed to the leg 2 without using a screw or an adhesive. However, a screw or an adhesive may be used for fixing.

[0047]

According to the first aspect of the present invention, a bearing device that can be easily attached to a leg of an existing chair without any modification is realized. When the person is not seated, the legs of the chair are supported by a plurality of rotatable spheres, so that the chair can be moved with a light force while the chair is supported on the floor. Since a plurality of spheres are provided, a small-sized sphere can be applied to provide a small-sized and small-sized and inexpensive bearing device. Since a plurality of spheres are provided, the surface pressure between the sphere and the floor can be reduced, which is also desirable in terms of floor protection. Since it becomes a small bearing device,
It is also advantageous in terms of the appearance of the chair. In the state where the person is seated, the plurality of spheres are in the retreat position and the main body block abuts on the floor surface, so there is no possibility that the floor surface will be depressed by the plurality of spheres, which is also advantageous in terms of chair stability. .

According to the second aspect of the present invention, since at least four spheres are provided, a sphere having a diameter of about 5 to 10 mm is applied, and the main body block has a small height of about 15 to 20 mm. The increase in the height of the seat surface of the chair can be kept small, and the surface pressure between the sphere and the floor surface can be kept sufficiently low. The other effects are the same as those of the first aspect.

According to the third aspect of the present invention, the retainer made of metal or synthetic resin for rotatably holding each sphere is provided in the housing hole of the main body block so as to be movable integrally with the sphere, and when the sphere is in the projecting position. Since the lower end portion of the retainer is configured to protrude from the lower end surface of the main body block, no gap is formed between the sphere and the retainer, and dust does not accumulate and the rotation performance of the sphere does not deteriorate. Further, since at least the lower part of the accommodation hole is a cylindrical hole, even if dust enters the accommodation hole, the dust is pushed out by the retainer. Therefore, durability and reliability can be ensured. Moreover, since the sphere is moved to the projecting position together with the retainer, when the sphere is at the projecting position, the distance between the lower end surface of the main body block and the floor surface can be increased,
It is less susceptible to floor irregularities, and is advantageous in terms of dust protection. When the retainer is made of metal, the holding performance for holding the sphere can be enhanced, and the durability can be enhanced. The other effects are the same as those of the first or second aspect.

According to the fourth aspect of the present invention, since each of the urging members comprises a plurality of disc springs, the size of the urging member can be reduced.
Further, it is advantageous in strengthening the urging force. The other effects are the same as those of the first or second aspect. According to the invention of claim 5, a plurality of attachment portions for fixing the main body block to a plurality of side surfaces at the lower end portion of the leg portion of the chair are provided.
The mounting strength for mounting the main body block to the leg of the chair can be sufficiently increased. Any one of claims 1 to 4
It has the same effect as the item.

According to the sixth aspect of the present invention, since the mounting portion is made of a soft synthetic resin material, it is advantageous in that the mounting portion is in close contact with the side surfaces of the legs of various sizes and shapes. The other effects are the same as those of the fifth aspect. According to the seventh aspect of the present invention, the mounting portion is configured to be flexible in a direction approaching and separating from the side surface of the leg portion of the chair. Therefore, the same effect as the sixth aspect is obtained. According to the invention of claim 8, since the mounting portion is formed of a metal plate, it is advantageous in fixing the mounting portion to the side surface of the leg with screws, and is also advantageous in increasing the strength of the mounting portion. The other effects are the same as those of the fifth aspect.

According to the ninth aspect of the present invention, since the buffer layer made of a soft synthetic resin material is provided at least on the upper end side portion of the main body block, the main body block is brought into close contact with the lower end surface of the leg and fixed. Therefore, the seating comfort when a person sits on the chair is improved, and the impact acting on the main body block can be absorbed. In addition, the same effect as any one of the first to eighth aspects is obtained. According to the tenth aspect of the present invention, a buffer layer made of a soft synthetic resin material is provided on at least the upper end side portion of the main body block, and the buffer layer and a plurality of flexible mounting portions are integrally formed. The buffer layer has the same effect as the ninth aspect. Since the buffer layer and the plurality of flexible attachment portions are integrally formed, the bonding strength between the main body block and the plurality of attachment portions can be secured. The other effects are the same as those of the seventh aspect.

According to the eleventh aspect of the present invention, since the main body block is fixed to the lower end surface of the chair by one or more screws, the main body block can be strongly and easily fixed to the lower end surface of the chair. Any one of claims 1 to 10
It has the same effect as the item. According to the invention of claim 12,
Since the main body block is fixed to the lower end surface of the chair leg using an adhesive or an adhesive, it is also possible to fix the main body block without damaging the chair leg, and the adhesive or the adhesive is used. When fixing with both screws,
The main body block can be firmly fixed to the lower end surface of the leg. In addition, the same effect as any one of the first to tenth aspects is obtained.

According to the thirteenth aspect of the present invention, the mounting portion has one
Alternatively, since the fixing portion is fixed to the side portion by a plurality of screws, the mounting portion can be strongly and easily fixed to the side portion of the leg.
In particular, it is suitable for the case where the mounting portion is made of a metal plate. In addition, the same effect as any one of claims 5 to 12 is obtained. According to the fourteenth aspect of the present invention, since the mounting portion is fixed to the side surface of the leg using an adhesive or an adhesive, the mounting portion is fixed to the side surface of the leg without damaging the leg with a screw. It becomes possible. Further, in the case of fixing using both the adhesive or the adhesive and the screw, the mounting portion can be firmly fixed to the side surface of the leg. Other claim 5
The same effects as in any one of Items 13 to 13 are achieved.

According to the fifteenth aspect, since the mounting portion is made of a transparent or substantially transparent material, it is advantageous in maintaining the appearance of the side surface of the leg. Other Claim 10
It has the same effect as.

According to the sixteenth aspect of the present invention, the main body block may be fixed to the lower end surface of the leg of the chair, or may not be fixed, and the main body block may be fixed to the lower end of the leg of the chair. Therefore, the degree of freedom in design is improved. Other claim 1
It has the same effect as.

[Brief description of the drawings]

FIG. 1 is a side view of a chair and a bearing device according to an embodiment of the present invention.

FIG. 2 is a plan view of the bearing device.

FIG. 3 is a sectional view taken along line III-III in FIG. 2;

FIG. 4 is a sectional view taken along line IV-IV of FIG. 2;

FIG. 5 is a longitudinal sectional view of a chair leg and a bearing device.

FIG. 6 is a longitudinal sectional view of a bearing device according to a modification.

FIG. 7 is a plan view of a bearing device according to another embodiment 1.

FIG. 8 is a longitudinal sectional view of the bearing device of FIG. 7;

FIG. 9 is a plan view of a bearing device according to another embodiment 2.

FIG. 10 is a sectional view taken along line XX of FIG. 9;

FIG. 11 is a sectional view taken along line XI-XI in FIG. 9;

FIG. 12 is a longitudinal sectional view of the bearing device of FIG. 9 and a leg of the chair.

FIG. 13 is a longitudinal sectional view of the bearing device of FIG. 9 and a leg of the chair.

FIG. 14 is a plan view of a bearing device according to another embodiment 3.

15 is a sectional view taken along line XV-XV in FIG.

16 is a sectional view taken along line XVI-XVI in FIG.

FIG. 17 is a plan view of a bearing device according to another embodiment 4.

18 is a sectional view taken along line XVIII-XVIII in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Chair 2 Legs 10, 30, 40, 50, 60, 70 Bearing device 11, 31, 41, 51, 61, 72 Body block 13, 52 Buffer layer 15 Retainer 16 Sphere 17, 73 Energizing member 18 Screw 43, 53, 63 Mounting part 54, 65 Adhesive or pressure-sensitive adhesive layer 55, 66 Release paper 71 Case

Claims (16)

[Claims] 1. A bearing device attachable to a surface of a lower end portion of a leg of a chair, comprising: a main body block fixed to at least a lower end surface of the leg portion of the chair; A plurality of spheres movably and rotatably mounted on the main body block to a protruding position that protrudes from the lower end surface and a retreat position that does not protrude from the lower end surface; and elastically bias the plurality of spheres toward the protruding position. A plurality of biasing members to be provided, wherein a plurality of spheres are in a protruding position against a load caused by the weight of the chair, and a plurality of spheres are in a retracted position when a person is seated. And a chair leg bearing device. 2. The chair leg bearing device according to claim 1, wherein at least four spheres are provided. 3. A retainer made of metal or synthetic resin for rotatably holding each of the spheres is provided in a housing hole of the main body block so as to be integrally movable with the spheres, and when the retainer is in the protruding position, the lower end of the retainer is the main body. 3. The bearing device for a chair leg according to claim 1, wherein the bearing device is configured to protrude from a lower end surface of the block. 4. The bearing device for a chair leg according to claim 1, wherein each of the urging members comprises a plurality of disc springs. 5. The chair according to claim 1, wherein a plurality of attachment portions are provided for fixing the main body block to a plurality of side portions of a lower end portion of a chair leg. A bearing device for a chair leg according to the above. 6. The bearing device for a chair leg according to claim 5, wherein the mounting portion is made of a soft synthetic resin material. 7. The chair leg bearing device according to claim 6, wherein the mounting portion is configured to be flexible in a direction approaching and separating from the side surface of the leg portion of the chair. 8. The bearing device for a chair leg according to claim 5, wherein the mounting portion is formed of a metal plate. 9. The bearing for a chair leg according to claim 1, wherein a buffer layer made of a soft synthetic resin material is provided at least on an upper end portion of the main body block. apparatus. 10. A buffer layer made of a soft synthetic resin material is provided on at least an upper end portion of the main body block, and the buffer layer and a plurality of flexible mounting portions are integrally formed. The chair leg bearing device according to claim 7. 11. The chair leg bearing device according to claim 1, wherein the main body block is fixed to a lower end surface of the chair by one or more screws. 12. The chair leg portion according to claim 1, wherein the main body block is fixed to a lower end surface of the leg portion of the chair using an adhesive or an adhesive. Bearing device. 13. The fixing device according to claim 5, wherein the mounting portion is fixed to the side surface portion by one or more screws.
13. The bearing device for a chair leg according to item 12. 14. The fixing device according to claim 5, wherein the mounting portion is fixed to the side portion using an adhesive or a pressure-sensitive adhesive.
The bearing device for a chair leg according to any one of claims 13 to 13. 15. The bearing device for a chair leg according to claim 10, wherein the mounting portion is made of a transparent or substantially transparent material. 16. A bearing device attachable to a surface of a lower end of a leg of a chair, wherein the bearing is fixed to a lower end of the leg so that a load acting on the leg of the chair can be transmitted to a floor surface. A plurality of spheres movably and rotatably mounted on the main body block to a protruding position that partially protrudes from a lower end surface of the main body block and a retracted position that does not protrude from the lower end surface of the main body block; A plurality of biasing members for elastically biasing the plurality of spheres toward the protruding position, wherein the plurality of spheres are in a protruding position against a load due to the weight of the chair, and the plurality of spheres are in a state where a person is seated. The bearing device for a chair leg, wherein the bearing device is configured to be in a retracted position.