JP7425470B2 - plain bearing - Google Patents

Description

The present invention relates to a sliding bearing having a synthetic resin sliding ring therein.

Slide bearings are used in many applications, but metal ball bearings are used for applications that require high precision and large loads, and metal ball bearings are used for applications that do not require high accuracy. Resins are often used instead.

As a sliding bearing using resin, for example, the sliding bearing disclosed in Patent Document 1 is known.

Japanese Patent Application Publication No. 2012-180896

The sliding bearing disclosed in Patent Document 1 has a complicated mechanism and is suitable for use in precision machines and the like. However, even if accuracy is not so necessary, a structure that can withstand heavy loads and vibrations and can be used outdoors for a long period of time is sometimes required.

Further, in the sliding bearing of Patent Document 1, the internal synthetic resin sliding member wears out, and when replacing it, it is necessary to remove the sliding member from the holding member and disassemble it.

The object of the present invention is to solve the above-mentioned problems by providing a sliding wheel that is low cost and easy to manufacture, has high load resistance and vibration resistance, and that allows replacement of the sliding wheel while it is fixed to the structure. Our goal is to provide bearings.

A sliding bearing according to the present invention for achieving the above object is a sliding bearing in which annular sliding wheels are arranged on both sides of one central member, and cover members are arranged on the outside of these sliding wheels in the axial direction . The central member includes a cylindrical outer ring, an annular flat part provided at openings at both ends of the outer ring facing radially inward, and an annular flat part continuous to the radially inner side of the annular flat part and axially inner. The sliding ring has a stepped portion extending inward in the radial direction and having a substantially L-shape when taken in cross section along a plane including the central axis of the outer ring; It is a substantially cylindrical body made of a synthetic resin material that is integrated with a thin cylindrical part, and the thin cylindrical part has a part to be inserted into a circular hole formed by a radial tip of a stepped part of the central member, The thick-walled cylindrical portion has a thick wall at an outer portion in the axial direction that contacts the stepped portion of the central member, and has an inner diameter that is the same as the inner diameter of the thin-walled cylindrical portion. At least part of the outer surface and the side surface is a sliding surface continuous along the circumferential direction, and the cover member includes a cylindrical portion to be inserted into the thin cylindrical portion and the thick cylindrical portion of the sliding ring, and a cylindrical portion that is inserted into the thin cylindrical portion and the thick cylindrical portion of the sliding ring, and a bottom plate having a hole provided for inserting a shaft rod into the cylindrical portion; It has a flange portion that abuts the annular plane portion and the thick-walled cylindrical portion of the central member, and the bottom plates of the cover member are butted against each other and connected, so that the shaft rod body can be inserted into the hole portion. It is characterized by

The sliding bearing of the present invention has a simple structure including a central member, a covering member, and two sliding wheels interposed between the central member and the covering member, and is easy to manufacture and can handle large loads. and can withstand vibration.

It is a front view of the sliding bearing of an Example. FIG. It is an exploded perspective view. It is a usage explanatory diagram.

The present invention will be explained in detail based on illustrated embodiments.
The sliding bearing according to the embodiment is a radial bearing, and FIG. 1 is a front view of the embodiment, FIG. 2 is a sectional view, and FIG. 3 is an exploded perspective view. The sliding bearing consists of one annular central member 1, two annular sliding wheels 2, 2', and two annular cover members 3, 3' stacked one on top of the other. Sliding wheels 2, 2' are arranged on both sides of the central member 1, and a cover member 3, 3' is arranged on the outside of these sliding wheels 2, 2', respectively.

The central member 1 mainly has a short cylindrical outer ring 1a, and narrow annular flat parts 1b and 1b' are provided further inside the edge of the opening of the outer ring 1a. Inside the annular plane parts 1b, 1b', step parts 1c, 1c' having a substantially L-shaped cross section are continuous, and the step parts 1c, 1c' have circular holes 1d, 1d at their tips. ' is formed. Note that although the space between the circular holes 1d and 1d' is a gap, this portion can also be made cylindrical and the circular holes 1d and 1d' arranged on both sides. Further, on the outside of the outer ring 1a, a pair of plate-like fixing parts 1e and 1f are provided in a substantially V-shape for fixing this sliding bearing to a structure.

The material of the central member 1 is not particularly limited, but it can be made of metal or rigid synthetic resin. If it is made of metal, it may be divided into several parts and processed, and these parts may be joined by welding or the like.

The sliding wheels 2, 2' are generally short cylindrical bodies made of synthetic resin. These sliding wheels 2, 2' consist of a thin cylindrical portion 2a inserted into the circular holes 1d, 1d' of the central member 1, and a thick cylindrical portion 2b continuous with the thin cylindrical portion 2a.

The outer diameter of the thin-walled cylindrical portion 2a substantially matches the diameter of the circular holes 1d and 1d', and the outer diameter of the thick-walled cylindrical portion 2b substantially matches the inner diameter of the side surface of the stepped portions 1c and 1c' of the central member 1. . The inner diameters of the thin-walled cylindrical portion 2a and the thick-walled cylindrical portion 2b are the same.

The length of the thin cylindrical portion 2a in the axial direction is shorter than 1/2 of the distance between the circular holes 1d and 1d', and the length of the thick cylindrical portion 2b is equal to the depth of the stepped portions 1c and 1c'. It is said to be approximately the same. Further, a plurality of recesses 2c and 2d are formed on the inner and outer surfaces of the thick-walled cylindrical portion 2b, and serve as grease reservoirs to be described later.

The synthetic resin forming the sliding wheels 2, 2' is made of a resin having excellent wear resistance and impact properties and self-lubricating properties, such as polyacetal, preferably polyoxymethylene (also known as POM or Duracon). Note that the resin forming the sliding wheels 2, 2' may contain a fibrous reinforcing material such as carbon fiber, aramid fiber, or glass fiber.

The cover members 3, 3' are composed of a cylindrical portion 3a, a bottom plate 3b, and a flange portion 3c. The cylindrical part 3a is a part to be inserted into the thin cylindrical part 2a and the thick cylindrical part 2b of the sliding wheels 2 and 2', and the outer diameter of the cylindrical part 3a and the inner diameter of the thick cylindrical part 2b substantially match. . The length of the cylindrical portion 3a is slightly longer than the length of the sliding wheels 2, 2' in the axial direction.

The bottom plate 3b is provided to close the tip of the cylindrical portion 3a, and a square hole 3d is formed in the bottom plate 3b for inserting another member, for example, a shaft rod having a square cross section. Further, a plurality of screw insertion holes 3e are provided on the side of the bottom plate 3b around the hole 3d. Although the hole 3d is square in order to insert the shaft rod having a square cross section, it may have any other suitable shape as long as the shaft rod does not rotate idly even if the shaft rod is inserted.

Further, the flange portion 3c is provided so as to protrude in an annular shape from the edge of the cylindrical portion 3a in an outward direction orthogonal to the axial direction of the cylindrical portion 3a. The flange portion 3c covers the thick cylindrical portion 2b of the sliding wheels 2, 2', and the edge of the flange portion 3c is in contact with the annular flat portion 1b, 1b' of the central member 1.

The bottom plates 3b of the cover members 3 and 3' can be integrally connected by screws 4 through screw insertion holes 3e when they are combined. Note that although FIG. 2 shows that the upper bottom plates 3b are connected to each other by the screws 4, the connection of the lower bottom plates 3b to each other by the screws 4 is omitted.

These cover members 3, 3', like the central member 1, can be made of metal or synthetic resin having rigidity, and in the case of being made of metal, they may be pressed products.

Note that the inner corners of the thick cylindrical portions 2b of the sliding wheels 2, 2' are made into smooth curved surfaces so that they come into contact with the corners of the stepped portions 1c, 1c' of the central member 1 and facilitate sliding. ing. Further, the outer corner portions of the thick cylindrical portions 2b of the sliding wheels 2, 2' are formed into smooth curved surfaces that come into contact with the flange portions 3c of the cover members 3, 3'. Correspondingly, the inner surfaces of the step portions 1c and 1c' of the central member 1 and the inner surfaces of the flange portions 3c of the cover members 3 and 3' are also curved.

To assemble the sliding bearing of the embodiment, first, the thin cylindrical portions 2a of the sliding wheels 2, 2' are inserted into the circular holes 1d, 1d' from both sides of the central member 1. At this time, the thick portion of the thick cylindrical portion 2b comes into contact with the step portions 1c and 1c' and is positioned. The length of the thin-walled cylindrical portions 2a of the sliding wheels 2, 2' is set such that the thin-walled cylindrical portions 2a on both sides do not come into contact with each other. The grease to be filled into the sliding bearing is applied around the thick-walled cylindrical portion 2b during this assembly process, and more preferably is filled into the recesses 2c and 2d.

Next, the cylindrical portions 3a of the cover members 3, 3' are inserted into the inner cylinders of the thick cylindrical portions 2b and thin cylindrical portions 2a of the sliding wheels 2, 2', and the cylindrical portions 3a of the cover members 3, 3' are closed by the flange portions 3c. At the same time, the peripheral edge of the flange portion 3c abuts on the annular flat portions 1b and 1b'.

Finally, the bottom plates 3b of the cover members 3 and 3' on both sides are butted against each other, the square holes 3d are aligned, and the screws 4 are inserted into the screw insertion holes 3e to connect the cover members 3 and 3'. Fix the connection. By applying the covering members 3, 3', the area around the thick-walled cylindrical portion 2b becomes a substantially sealed space, and grease does not leak out.

It is preferable to apply a lubricant such as grease to the sliding surfaces of the sliding wheels 2, 2', and by applying the grease as described above, the friction torque of the sliding wheels 2, 2' can be reduced. As a result, wear and deformation of the sliding wheels 2, 2' and surrounding members can be prevented, and the life of the sliding wheels 2, 2' can be extended. Grease is stably supplied to the sliding surface over a long period of time by the recesses 2c and 2d that hold the grease.

FIG. 4 is an explanatory diagram of how this sliding bearing is used. Sliding bearings are used, for example, to support the rotation of shaft A, which is a winding shaft that moves up and down a light-shielding or heat-insulating curtain in a greenhouse, and a large downward load is applied to shaft A. .

The central member 1 is fixed to a greenhouse structure B via fixing parts 1e and 1f, and a shaft rod A having a square cross section is inserted into a square hole 3d of the cover members 3 and 3'. The shaft body A is connected to an electric motor (not shown), and is rotatably supported by a structure B via a sliding bearing.

When the shaft body A is rotationally driven by the electric motor, the cover members 3 and 3' rotate in conjunction with each other through the hole 3d. In this case, the cover members 3, 3' rotate with respect to the central member 1 via sliding wheels 2, 2'. The sliding wheels 2, 2' have self-lubricating properties and are coated with grease, so that they slide circumferentially relative to the central member 1, thereby ensuring smooth rotation of the cover members 3, 3'. encourage In particular, since the sliding bearing according to this embodiment has two sliding wheels 2 and 2', it can sufficiently support a large load in the radial direction caused by the shaft A.

If the sliding wheels 2, 2' have to be replaced due to wear, etc., remove the covering members 3, 3' and one side of the sliding wheels 2, 2' from the shaft A while still attached to the structure B. It can be removed by moving in the axial direction and a new covering member 3, 3' and one side of the sliding ring 2, 2' can be moved and installed on the shaft A. When installing a new cover member 3, 3' and one side of the sliding wheels 2, 2', use the remaining cover member 3, 3' and one side of the sliding wheels 2, 2' to attach the sliding bearing to the shaft body A. is retained, making it easy to complete the installation process.

With conventional sliding bearings, it was necessary to remove the sliding bearing from the shaft rod body when replacing the sliding member, but with the sliding bearing of this embodiment, the sliding bearing can be left attached to the shaft rod body A. , it is possible to replace the sliding wheels 2, 2' on one side.

The sliding bearing of the present invention includes a central member 1, cover members 3, 3', and two sliding wheels 2, 2' interposed between the central member 1 and the cover members 3, 3'. , has a simple structure, is easy to manufacture, and can withstand large loads and vibrations.

1 Central member 1a Outer ring 1b, 1b' Annular plane part 1c, 1c' Step part 1d, 1d' Circular hole 1e, 1f Fixed part 2, 2' Sliding ring 2a Thin cylindrical part 2b Thick cylindrical part 2c, 2d Recessed part 3, 3' Covering member 3a Cylindrical part 3b Bottom plate 3c Flange part 3d Hole part 3e Screw insertion hole

Claims (6)

A sliding bearing in which annular sliding wheels are arranged on both sides of one central member, and cover members are arranged on the axial outside of these sliding wheels,
The central member includes a cylindrical outer ring, an annular plane part provided at openings at both ends of the outer ring facing radially inward, and continuous to the radially inner side of the annular plane part and extending axially inward. After that, the step part falls radially inward and has a substantially L-shape when the cross section is taken from a plane including the central axis of the outer ring ,
The sliding ring is a substantially cylindrical body made of a synthetic resin material that includes a thin cylindrical part and a thick cylindrical part, and the thin cylindrical part has a circular shape formed by the radial tip of the stepped part of the central member. The thick-walled cylindrical portion has a portion inserted into the hole, and the thick-walled cylindrical portion has a thick wall at an outer portion in the axial direction that abuts the step portion of the central member, and has an inner diameter that is the same as an inner diameter of the thin-walled cylindrical portion. and at least part of the inner and outer surfaces and side surfaces of the thick-walled cylindrical portion are continuous sliding surfaces along the circumferential direction,
The cover member includes a cylindrical portion to be inserted into the thin-walled cylindrical portion and the thick-walled cylindrical portion of the sliding ring, and a bottom plate that closes the tip of the cylindrical portion and has a hole provided for inserting the shaft rod. and a flange portion provided on the axially outer side of the inlet side of the cylindrical portion, covering the thick-walled cylindrical portion of the sliding ring and abutting the annular plane portion and the thick-walled cylindrical portion of the central member. death,
A sliding bearing characterized in that the bottom plates of the cover member are butted against each other and connected, so that the shaft rod can be inserted into the hole. The outer diameter of the thin-walled cylindrical portion substantially matches the diameter of the circular hole, and the outer diameter of the thick-walled cylindrical portion substantially matches the inner diameter of the side surface of the stepped portion. sliding bearing. The sliding bearing according to claim 1 or 2, wherein axially inner and axially outer corners of the thick-walled cylindrical portion have smooth curved surfaces. The sliding bearing according to any one of claims 1 to 3, wherein the thick-walled cylindrical portion is surrounded by a substantially sealed space. The sliding bearing according to any one of claims 1 to 4, wherein a part of the central member is provided with a fixing part that connects to other members. The sliding bearing according to any one of claims 1 to 5, characterized in that a plurality of recesses are formed around the thick-walled cylindrical portion to serve as grease reservoirs.

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