JPH0680030U - Fastening device for shaft and rotor with a single nut - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a fastening device for a shaft and a rotating body, which utilizes the wedge action of an inner ring and an outer ring formed with complementary tapered surfaces, and which can be fastened with a single nut. To do. [Structure] The fastening device 10 includes an inner ring 20, an outer ring 30, and a nut 40. The inner ring 20 has an outer peripheral taper surface 22. A groove 27 is formed on the larger diameter side of the tapered surface 22. The groove 27 is formed by the protrusion 23 and the retaining ring 26. The outer ring 30 has a tapered surface 32 on the inner peripheral side. The tapered surface 32 has a shape complementary to the tapered surface 22. The outer ring 30 has, on the side where the diameter of the tapered surface 32 is large, a protrusion 33 having a male screw portion 34 formed therein. The nut 40 has a protrusion 43 fitted into the groove 27 and a female screw portion 44 screwed into the male screw portion 34. When the nut 40 is turned, the inner ring 20 and the outer ring 30
Move relative to each other, and the wedge action causes the shaft and the rotating body to be fastened.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a fastening device for fastening a rotating body such as a sprocket or a gear to a shaft without using a key.

[0002]

[Prior art]

 FIG. 4 shows a conventional fastening device. This type of fastening device 210 fastens the shaft 12 and the rotating body 14 by the surface pressure generated by the wedge action of the tapered surfaces 222 and 232 of the inner ring 220 and the outer ring 230. A large number of clamping bolts 240 arranged on the circumference are used in producing the wedge action.

[0003]

[Problems to be solved by the device]

 However, in the fastening device 210 as described above, the fastening bolts 240 must be sequentially and evenly tightened, which is troublesome. In particular, when the fastening device is applied to a shaft having a small diameter, for example, a shaft having a diameter of 10 mm or less, there are the following problems. That is, there is a limit to reducing the size of the tightening bolt 240. Therefore, the tightening bolt 240 becomes large with respect to the inner ring 220 and the outer ring 230, so that the entire fastening device cannot be made compact.

[0004]

[Means for Solving the Problems]

 The first aspect of the present invention is to provide a fastening device for a shaft and a rotating body, which has an inner ring and an outer ring having mutually complementary tapered surfaces, wherein the inner ring has a groove portion on the larger diameter side of the tapered surface. The outer ring has a male threaded portion on the larger diameter side of the tapered surface, and a nut having a projecting portion that fits into the groove portion and a female threaded portion that is screwed into the male threaded portion is used so that the two rings are axially opposed to each other. The above-mentioned problem was solved by the fastening device which caused the movement. Secondly, the present invention provides a fastening device for a shaft and a rotating body having an inner ring and an outer ring having mutually complementary tapered surfaces, wherein the inner ring has a groove portion on the larger diameter side of the tapered surface. The outer ring has a male threaded portion on the larger diameter side of the tapered surface, a nut having a grooved portion facing the grooved portion and a female threaded portion screwed into the male threaded portion, and the grooved portion of the inner ring. A large number of balls are loaded between the groove portion of the nut and the groove portion of the nut, and the above-mentioned problem is solved by the fastening device in which the nut causes relative movement in the axial direction of the both rings.

[0005]

[Action]

 The nut is allowed to rotate with respect to the inner ring, but is prevented from moving in the axial direction. When the nut is tightened, the inner ring and outer ring move relative to each other in the axial direction. As a result, due to the wedge action of the tapered surface, the inner ring contracts and the outer ring expands, and the surface pressure generated between them causes the shaft and the rotating body to be fastened. Then, the torque is transmitted by the frictional force.

[0006]

【Example】

 1 and 2 show a first embodiment of a fastening device according to the present invention. The fastening device 10 includes an inner ring 20, an outer ring 30, and a nut 40. Reference numeral 12 is a shaft, and 14 is a rotating body.

The inner ring 20 is formed with a cylindrical inner peripheral surface 21 through which the shaft 12 is inserted and an outer peripheral taper surface 22. The inner ring 20 has, at one end on the larger diameter side of the tapered surface 22, an annular protrusion 23 that protrudes outward in the radial direction, a slot 24 formed on the outer side thereof, and a notch 25 on the outer side thereof. Has been formed. A retaining ring 26 is fitted on the slot 24. A groove 27 is formed by the protrusion 23 and the retaining ring 26. The inner ring 20 has an axial slit (not shown).

The outer ring 30 is formed with a cylindrical outer peripheral surface 31 that can be inserted into the rotating body 14 and an inner peripheral taper surface 32. The tapered surface 32 has a shape complementary to the tapered surface 22 of the inner ring 20. The outer ring 30 is formed with a protrusion 33 that protrudes outward in the radial direction on the side where the diameter of the tapered surface 32 is large. A male screw portion 34 is formed on the outer periphery of the protrusion 33. An axial gap of a certain width is secured between the protrusion 33 and the protrusion 23 of the inner ring.

The nut 40 has a protrusion 43 that fits into the groove 27, a female screw portion 44 that is screwed into the male screw portion 34, and an annular contact portion 45 that protrudes in the axial direction so as to contact the rotating body 14. . The outer diameter of the nut 40 is a hexagonal shape that engages with a spanner or the like. Note that this shape may be a quadrangular shape, or may be a shape such as a notch formed in parallel with each other.

Next, the fastening operation will be described. Since the protrusion 43 of the nut 40 is fitted in the groove 27, rotation is permitted but axial movement with respect to the inner ring 20 is prevented. Therefore, when the nut 40 is turned, the outer ring 30 moves leftward in the drawing. The inner ring 20 and the outer ring 30 generate surface pressure on the shaft 12 and the rotating body 14 by the wedge action of the tapered surfaces 22 and 32, and as a result, the shaft 12 and the rotating body 14 are fastened.

During operation, the contact portion 45 of the nut 40 contacts the side surface of the rotating body 14. Even if the outer ring 30 moves in the axial direction, the rotating body 14 is prevented from moving by the nut 40, and the axial positioning is accurately performed. When turning the nut 40, it is desirable to fix the notch 25 of the inner ring 20 with a wrench or the like in order to prevent the inner ring 20 from rotating together.

To release the tightened state, the nut 40 may be rotated in the opposite direction, and at that time, the outer ring 30 moves to the right in the figure and the wedge action is released.

3 and 4 show a second embodiment of the fastening device according to the present invention. The fastening device 110 of this embodiment differs from the fastening device 110 of the first embodiment in the relationship between the inner ring and the nut. The inner ring 120 has an annular groove 127 on the outer peripheral side at one end on the larger diameter side of the tapered surface 122. The nut 140 has a groove portion 147 facing the groove portion 127. A large number of balls 150 are loaded between the groove portions 127 and 147. The nut 140 has a hole (not shown) extending from the outer circumference to the groove 147, and the ball 150 is loaded through this hole. After the ball 150 is loaded, the hole is closed by an appropriate means such as a plug. The other structure is substantially the same as that of the first embodiment, and the description thereof is omitted.

In the fastening device 110 of the present embodiment, when the nut 140 is turned, the balls 150 roll in the grooves 127 and 147, so the sliding friction in the first embodiment is replaced with rolling friction. . Therefore, the fastening device 110 can be fastened with a relatively small force.

[0015]

[Effect of device]

 In the present invention, since the inner ring and the outer ring are moved relative to each other in the axial direction by using a single nut, the number of fastening steps can be significantly reduced, and the bolts can be tightened uniformly as in the past. There is no need for the troublesome work. Further, by eliminating a large number of conventional fastening bolts, the fastening device can be made compact, and the practical effect is particularly remarkable in the fastening device having a small diameter of 10 mm or less.

According to the second aspect of the invention, in addition to the above effect, the force required for tightening the nut is reduced, and the tightening operation is facilitated.

[Brief description of drawings]

FIG. 1 is an axial sectional view of a first embodiment of a fastening device according to the present invention.

FIG. 2 is a left side view of the fastening device of FIG.

FIG. 3 is an axial sectional view of a second embodiment of the fastening device according to the present invention.

FIG. 4 is an axial sectional view of a conventional fastening device.

[Explanation of symbols]

 10,110 Fastening device 12 Shaft 14 Rotating body 20,120 Inner ring 22,122 Tapered surface 27,127 Groove portion 30,130 Outer ring 32 Tapered surface 34 Male screw portion 40,140 Nut 43 Projection portion 44 Female screw portion 147 Groove portion 150 Ball

Claims (2)

[Scope of utility model registration request] 1. A fastening device for a shaft and a rotating body having an inner ring and an outer ring having mutually complementary tapered surfaces, wherein the inner ring has a groove portion on the larger diameter side of the tapered surface, The ring has a male threaded portion on the larger diameter side of the tapered surface, and a nut having a projecting portion that fits into the groove portion and a female threaded portion that is screwed into the male threaded portion causes axial relative movement of both rings. A fastening device characterized by being tightened. 2. A fastening device for a shaft and a rotary body, which has an inner ring and an outer ring having mutually complementary tapered surfaces, wherein the inner ring has a groove portion on the larger diameter side of the tapered surface, The ring has a male screw portion on the larger diameter side of the tapered surface, and has a nut having a groove portion facing the groove portion and a female screw portion screwed into the male screw portion, and the groove portion of the inner ring and the nut. A fastening device, characterized in that a large number of balls are loaded between the groove portions, and the nut causes relative movement in the axial direction of the both rings.