JPH01275917A - Friction shaft joint - Google Patents

Abstract

PURPOSE:To save material cost, make work very easy and make fixing work simpler by drilling taper hole between double pipe contact faces through reamer machining or the like with cylindrical straight pipes used in a piled state. CONSTITUTION:A bushing 14 incorporates in advance tightly a cylindrical inner ring 15 engaging to outer peripheral surface of a shaft 13 and a cylindrical outer ring 16 with its inner diameter engaging to outer peripheral surface of the inner ring 15. After inserting a taper pin 20 in a taperhole 17, when a fixing screw 21 is rotated, the taper pin 20 is pushed in deep. The outer ring 16 is thereby pressed tight to the inner peripheral surface of a fixing hole 12, and simultaneously the bushing 14 is expanded, and a housing 11 and the shaft 13 are unified in one body mechanically. Thus, this enables the saving of the material cost, the easiness of the work and the simplification of the attaching work.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a friction shaft coupling that integrally fixes a cylindrical shaft inserted into a mounting hole of a housing with a bushing.

(Prior Art) Many conventional friction shaft joints utilize wedge action. For example, as shown in FIGS. 11 and 12, a cylindrical shaft 3 inserted into a mounting hole 2 of a housing 1 is They are fixed together via a joint member 4. The joint member 4 includes a cylindrical outer ring 5 with a tapered chevron-shaped cross section on the inside that is fitted into the mounting hole 2 of the housing 1, and a cylindrical outer ring 5 with a taper with a chevron-shaped cross section on the outside that is fitted into the shaft 3. A cylindrical inner ring 6 with a tapered shape, a key ring 7.8 having a trapezoidal cross section formed into a ring shape, and having a screw hole on one side and a through hole on the other side, and a key ring 7.8. is composed of a bolt 9. Housing 1
The outer ring 5 fitted into the mounting hole 2 and the inner ring 6 fitted onto the shaft 3 are arranged concentrically with an interval between them, and a key ring is inserted between each ring 5 and 6 from one side. A key ring 8 is inserted into each of the key rings 7 from the other side, and a bolt 9 is inserted into the through hole of the key ring 8 and tightened by screwing it into the screw hole of the key ring 7. As a result, each key ring 7.8 is drawn toward each other, and the outer ring 5 is moved toward the housing 1 and the inner ring 6 is moved toward the shaft 3.
The shaft 3 and the housing 1 are fixed together by expanding each side.

(Problems to be Solved by the Invention) In the conventional friction shaft coupling described above, the chevron-shaped tapered surfaces must be separately machined for the outer ring and the inner ring, and there are two types that are also machined separately. Each key ring is required, which increases processing costs, and each key ring must be inserted separately from both sides, making the installation process complicated.

Therefore, the present invention provides a friction shaft joint that can solve these problems.

(Means for Solving the Problems) The gist of the present invention is to integrally fix a housing and a cylindrical shaft inserted into a mounting hole of the housing with a bushing interposed between the housing and the shaft. The bushing is a friction shaft coupling, and the bushing includes a cylindrical inner ring with an inner diameter that fits on the outer circumferential surface of the shaft, and a cylindrical inner ring with an outer diameter that fits on the inner circumferential surface of the mounting hole of the housing. It is formed of a double tube with a cylindrical outer ring having an inner diameter that fits into the surface, and extends along between the overlapping joint surfaces of the double tube, and is spaced at intervals in the circumferential direction. A plurality of taper holes are provided, and a tapered bottle is press-fitted into the taper holes so that the outer ring is pressed against the inner circumferential surface of the mounting hole of the housing, and the inner ring is pressed against the inner circumferential surface of the shaft. This is a friction shaft joint in which the diameter of the bushing is expanded so as to come into pressure contact with the bushing.

(Example) The present invention will be explained below based on the illustrated example. First, FIGS. 1 and 2 show a friction shaft joint according to a first embodiment. The bushing 14, which integrally fixes the housing 11 and the cylindrical shaft 13 inserted into the mounting hole 12 of the housing 11, is constructed of a double tube as shown in FIGS. 3 and 4. This double-tube bushing 14 includes a cylindrical inner ring 15 having an inner diameter that fits on the outer peripheral surface of the shaft 13, and a mounting hole 12 of the housing 11.
a cylindrical outer ring 16 having an outer diameter that fits on the inner circumferential surface of the inner ring 15 and an inner diameter that fits on the outer circumferential surface of the inner ring 15;
They are assembled in a fitted state in advance. This bushing 14 is provided with tapered holes 17 and straight holes 18 that extend along the overlapping joint surfaces of the double tubes and are alternately arranged at intervals in the circumferential direction. A screw hole 19 is bored at the entrance on the large diameter side of the tapered hole 17.

The bush 14 is inserted between the mounting hole 12 of the housing 11 and the shaft 13, and the taper pin 2 is inserted into the taper hole 17.
After inserting screw 2, tighten screw 2 into screw hole 19.
1, the taper bottle 20 is press-fitted to the back.

As a result, the outer ring 16 is attached to the housing 11.
The bushing 14 is enlarged in diameter so that it comes into pressure contact with the inner peripheral surface of the mounting hole 12 and the inner ring 15 comes into pressure contact with the outer peripheral surface of the shaft 13, thereby fixing the housing 11 and the shaft 13 together. Incidentally, the straight hole 18 is for releasing stress during diameter expansion.

Next, a friction shaft joint according to a second embodiment will be explained with reference to FIGS. 5 to 8, and the same parts as those in the first embodiment will be described with the same reference numerals. As shown in FIGS. 7 and 8, the bushing 22 is formed of a double cylinder made up of an inner ring 23 and an outer ring 24 which are pressed together in a press-fitted state similar to the previous embodiment, and between the joining surfaces of the double cylinder. Tapered holes 25 and screw holes 26 are formed extending along the circumferential direction and alternately arranged at intervals in the circumferential direction.

As shown in FIGS. 5 and 6, the bush 22 is inserted between the mounting hole 12 of the housing 11 and the shaft 13, and after inserting the taper pin 27 into the taper hole 25, a donut is inserted into the opening surface on the large diameter side. A shaped press plate 28 is attached, and when the screw 29 is rotated, the tapered bottle 27 is pushed to the back by the press plate 28. It is press-fitted until the end. As a result, the outer ring 24 comes into pressure contact with the inner circumferential surface of the mounting hole 12 of the housing 11, and the inner ring 23
The diameter of the bushing 22 is expanded by pressing against the outer peripheral surface of the bushing 22, and the housing 11 and the shaft 13 are fixed together.

In addition, for the bushes 14.22 of each of the above-mentioned examples,
For example, as shown in Fig. 9, slit-shaped holes 30° 31 are provided on the inner and outer circumferential surfaces to release stress during the diameter expansion, or as shown in Fig. 10, the shaft 13 is keyed to the inner circumferential surface. A keyway 32 may also be provided.

(Effects of the Invention) As is clear from the embodiments described above, in the present invention, cylindrical straight pipes are used in a superposed state as the outer ring and the inner ring constituting the bushing, and the double pipes are joined by reaming or the like. Since inner and outer tapered surfaces are simultaneously formed by drilling a tapered hole between the surfaces, the material cost is lower and processing is extremely easier than in the conventional friction shaft joint described above. Furthermore, the bushing can be expanded in diameter by simply press-fitting the taper pin into the taper hole from one side, and the housing and shaft can be fixed together, making the installation process easy.

[Brief explanation of the drawing]

Fig. 1 is a plan view of a friction shaft joint according to the first embodiment of the present invention, Fig. 2 is a sectional view taken along the line ■-■ in Fig. 1, and Fig. 3 is a plan view of a bushing that is a main part of the friction shaft joint. , FIG. 4 is a sectional view taken along the line IV--IV in FIG. 3, FIG. 5 is a plan view of a friction shaft joint according to the second embodiment of the present invention, FIG. The figure is a plan view of the bushing, which is the main part of the friction shaft coupling, and Figure 8 is the 7th
Figures 9 and 10 are plan views schematically showing modified examples of the bushing, Figure 11 is a plan view of a conventional friction shaft joint, and Figure 12 is a sectional view of the center of the same. be. [Explanation of symbols] 11...Housing 12...Mounting hole 13...
・Shaft 14, 22...Button 15.2
3... Inner ring 16.24... Outer ring 17.25... Tapered hole 18... Straight hole 1
9.26...Screw hole 20.27 Taper pin 21
．． 29 Tighten with screws 28...Press plate Q Fig. 2 Fig. 1 Fig. 12 Fig. 11

Claims (1)

[Claims] A friction shaft coupling that integrally fixes a housing and a cylindrical shaft inserted into a mounting hole of the housing with a bush interposed between the housing and the shaft,
The bushing includes a cylindrical inner ring having an inner diameter that fits on the outer circumferential surface of the shaft, an outer diameter that fits on the inner circumferential surface of the mounting hole of the housing, and an inner diameter that fits on the outer circumferential surface of the inner ring. It is formed of a double tube with a cylindrical outer ring, and a plurality of tapers are arranged at intervals in the circumferential direction and extend along between the overlapping joint surfaces of the double tube. A hole is bored, and a taper pin is press-fitted into the taper hole so that the outer ring is pressed against the inner peripheral surface of the mounting hole of the housing, and the inner ring is pressed against the outer peripheral surface of the shaft. Friction shaft coupling made by expanding the diameter.