JPH0573524U - Ring-shaped member fixing structure - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] A ring-shaped member fixing structure that can reduce the dimensions such as the outer diameter of the ring-shaped member by reducing the stress generated in the ring-shaped member. I will provide a. [Structure] Outer peripheral surface 12a of disk-shaped member (rotating plate) 12
By fitting the ring-shaped member (ring-shaped magnet) 13 to the ring-shaped member 13,
In the fixing structure of the ring-shaped member, the outer peripheral surface 12a of the disc-shaped member 12 and the inner peripheral surface 13a of the ring-shaped member 13 fitted to the outer-peripheral surface 12a are aligned with the axis of the disc-shaped member 12. The disk-shaped member 12 is formed in a conical shape with a center line.
In this configuration, an elastic holding member 12c that exerts an elastic force is provided so as to prevent the ring-shaped member 13 from moving along the outer peripheral surface 12a in the direction of decreasing the diameter.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a ring-shaped member fixing structure for fixing a ring-shaped member to the disk-shaped member by fitting the ring-shaped member on the outer peripheral surface of the disk-shaped member.

[0002]

[Prior Art]

 Conventionally, as a fixing structure of this type of ring-shaped member, for example, one shown in FIGS. 7 to 9 is known as being applied to a rotor of a rotation sensor. That is, the rotor 1 has a ring-shaped magnet (ring-shaped member) 4 fitted to the outer periphery of a rotary plate (disc-shaped member) 3 having a rotation shaft 2 as the center of rotation.

The rotary plate 3 is made of resin in a disc shape, and is designed to reliably connect the rotating shaft 2 and the ring-shaped magnet 4 by insert molding. The ring-shaped magnet 4 is magnetized into multiple poles at predetermined intervals in the circumferential direction, and the rotation sensor described above captures changes in the magnetic poles of the ring-shaped magnet 4 rotating about the rotating shaft 2. Thus, the rotation speed is detected. The rotary plate 3 and the ring-shaped magnet 4 fitted to the rotary plate 3 constitute a fixed structure of the ring-shaped member.

Further, as a fixing structure of the ring-shaped member, as shown in FIG. 10, a V-shaped groove 3a is formed on the outer peripheral surface of the rotary plate 3, and a ring-shaped groove is formed so as to be fitted into the groove 3a. There is also a structure in which a V-shaped convex strip 4a is formed on the inner peripheral surface of the magnet 4 so that the rotary plate 3 and the ring-shaped magnet 4 are securely connected.

[0005]

[Problems to be solved by the device]

 However, in the conventional fixing structure of the ring-shaped member as described above, since the rotary plate 3 is made of resin, the linear thermal expansion coefficient of the rotary plate 3 is much larger than the linear thermal expansion coefficient of the ring-shaped magnet 4. Therefore, there is a drawback that tensile stress is generated in the ring-shaped magnet 4 as the temperature rises. Therefore, the ring-shaped magnet 4 must be sufficiently resistant to the tensile stress, and as a result, the ring-shaped magnet 4 has a large outer diameter and thickness. It was.

The present invention has been made to solve the above-mentioned problems, and the purpose thereof is to reduce the stress generated in the ring-shaped member to reduce the dimensions such as the outer diameter of the ring-shaped member. The object of the present invention is to provide a fixing structure for a ring-shaped member capable of achieving the above.

[0007]

[Means for Solving the Problems]

 In order to achieve the above object, the invention according to claim 1 is a ring-shaped member for fixing the ring-shaped member to the disk-shaped member by fitting the ring-shaped member on the outer peripheral surface of the disk-shaped member. In the member fixing structure, the outer peripheral surface of the disc-shaped member and the inner peripheral surface of the ring-shaped member fitted to the outer peripheral surface are formed in a conical surface shape with the axis of the disc-shaped member as the center line. The disk-shaped member is provided with an elastic holding member that exerts an elastic force so as to prevent the ring-shaped member from moving in the direction of decreasing the diameter along the outer peripheral surface. It has a feature.

Further, according to a second aspect of the invention, a ring-shaped member for fixing the ring-shaped member to the disc-shaped member by fitting the ring-shaped member on the outer peripheral surface of the disc-shaped member. The disc-shaped member is provided with a plurality of holes penetrating in the axial direction at a predetermined interval in the circumferential direction, and the connecting portion connecting the adjacent holes to each other is the circular shape. The feature is that it is formed obliquely with respect to the normal line extending in the radial direction from the axis of the plate member.

[0009]

[Action]

 In the ring-shaped member fixing structure according to claim 1 configured as described above, when the coefficient of thermal expansion of the disk-shaped member is larger than that of the ring-shaped member, the temperature rises from room temperature. Along with this, the ring-shaped member moves along the outer peripheral surface of the disc-shaped member in the direction in which the diameter becomes smaller, against the elastic force. That is, since the increase in the outer diameter of the disc-shaped member is larger than the increase in the inner diameter of the ring-shaped member, the ring-shaped member is relatively moved along the outer peripheral surface of the disc-shaped member in the direction of decreasing diameter. Move. Therefore, almost no tensile stress is generated in the ring-shaped member, and the elastic force from the elastic holding member reliably maintains the connected state between the ring-shaped member and the disc-shaped member.

Further, when the temperature drops from room temperature, for example, when used in cold regions, the decrease in the outer diameter of the disk-shaped member is smaller than the decrease in the inner diameter of the ring-shaped member. Since the ring-shaped member is large, the ring-shaped member moves in the direction in which the diameter increases along the outer peripheral surface of the disc-shaped member due to the elastic force from the elastic holding member. Therefore, in this case, there is no gap between the ring-shaped member and the disc-shaped member, and the connected state between the ring-shaped member and the disc-shaped member is reliably maintained. Of course, no compressive stress is generated in the ring-shaped member.

Further, when the coefficient of thermal expansion of the disk-shaped member is smaller than the coefficient of thermal expansion of the ring-shaped member, the ring-shaped member becomes a disk-shaped member as the temperature rises, contrary to the above-described action. The diameter of the ring-shaped member increases along the outer peripheral surface of the disk-shaped member, and as the temperature decreases, the ring-shaped member moves in the direction of smaller diameter along the outer peripheral surface of the disk-shaped member.

Next, in the ring-shaped member fixing structure according to the second aspect, since the connecting portion is formed obliquely with respect to the normal, the connecting portion is spring-loaded against the force applied to the outer peripheral surface. To work. Therefore, if the coefficient of thermal expansion of the disk-shaped member is larger than that of the ring-shaped member, the increase in the outer diameter of the disk-shaped member will increase as the temperature rises from room temperature. The dimension dx is larger than the increase of the inner diameter of the member by, for example, the dimension dx, but the dimension dx is absorbed by the bending of the coupling portion (that is, the inclination of the coupling portion with respect to the normal increases). Therefore, tensile stress is hardly generated in the ring-shaped member.

Further, when the temperature drops from room temperature, for example, when it is used in a cold region, the decrease amount of the outer diameter of the disk-shaped member is smaller than the decrease amount of the inner diameter of the ring-shaped member. Also, for example, the size increases by dx ', and a gap is about to be generated between the disc-shaped member and the ring-shaped member, but the connecting portion extends (that is, the inclination of the connecting portion with respect to the normal line decreases). This absorbs the dimension dx '. Therefore, no gap is generated between the disc-shaped member and the ring-shaped member, and the coupled state of the disc-shaped member and the ring-shaped member is maintained.

Further, when the coefficient of thermal expansion of the disk-shaped member is smaller than the coefficient of thermal expansion of the ring-shaped member, the outer diameter of the disk-shaped member increases as the temperature rises, contrary to the above-described action. The amount becomes smaller than the increase in the inner diameter of the ring-shaped member, the connecting part expands, and the decrease in the outer diameter of the disc-shaped member decreases as the temperature decreases. It becomes smaller and the connecting part bends.

[0015]

【Example】

 Hereinafter, a first embodiment and a second embodiment of the present invention will be described with reference to FIGS. First, a first embodiment will be described with reference to FIGS. However, elements common to the constituent elements of the conventional example shown in FIGS. 7 to 9 are designated by the same reference numerals, and description thereof will be omitted.

As shown in FIGS. 1 and 2, the rotor 11 has a ring-shaped magnet (ring-shaped member) 13 fitted on the outer periphery of a rotary plate (disc-shaped member) 12 having a rotation axis 2 as a rotation center. It is a thing. The rotary plate 12 is made of a resin such as nylon or polyphenylene sulfide and formed in a disk shape, and is formed by insert molding so as to be in close contact with the rotary shaft 2 made of metal. The outer peripheral surface 12a of the rotary plate 12 is formed in a conical surface shape with the axis of the rotary shaft 2 as the center line, and the plate surface 12b on the small diameter side of the outer peripheral surface 12a has a constant interval in the circumferential direction. Here, the four elastic holding members 12c are integrally formed.

As shown in FIG. 3, the elastic holding member 12c projects from the plate surface 12b so as to draw an arc, and the front end surface 12d thereof reaches the lateral position of the outer peripheral surface 12b, and particularly the front end surface 12d. It is elastically deflected by an external force acting almost perpendicularly to, and as a result, an elastic force is generated as a reaction force. The tip surface 12d is formed substantially perpendicular to the axis of the rotary shaft 2.

The ring-shaped magnet 13 is magnetized into multiple poles at predetermined intervals in the circumferential direction, and its inner peripheral surface 13 a is fitted to the outer peripheral surface 12 a of the rotary plate 12. It is formed in a conical shape. As shown in FIG. 3, one end surface 13b of the ring-shaped magnet 13 comes into contact with the tip surface 12d of the elastic holding member 12c, and the elastic member 12d emits elastic force. Due to the force, the inner peripheral surface 13a comes into close contact with the outer peripheral surface 12a of the rotating plate 12 and is surely connected to the outer peripheral surface 12a.

In the fixed structure of the ring-shaped member composed of the rotary plate 12 and the ring-shaped magnet 13 as described above, since the rotary plate 12 is made of resin, the thermal expansion coefficient of the rotary plate 12 is smaller than that of the rotary plate 12. It is larger than the coefficient of thermal expansion of the ring-shaped magnet 13. Therefore, when the temperature rises from room temperature, for example, when a tachometer having the rotating plate 12 and the ring-shaped magnet 13 is provided in the engine or the like, as shown in FIG. While moving against the elastic force from the member 12c, it moves along the outer peripheral surface 12a of the rotary plate 12 in the direction of decreasing the diameter.

That is, as the temperature increases, the amount of increase in the diameter of the outer peripheral surface 12 a of the rotary plate 12 is larger than the amount of increase in the diameter of the inner peripheral surface 13 a of the ring-shaped magnet 13. It moves relative to the outer peripheral surface 12a of the rotary plate 12 in the direction of decreasing the diameter. Therefore, almost no tensile stress is generated in the ring-shaped magnet 13, and the connection state between the ring-shaped magnet 13 and the rotary plate 12 is reliably maintained by the elastic force from the elastic holding member 12c.

Further, when the temperature drops from room temperature, for example, when the assembly assembled at room temperature is used in cold regions, the amount of decrease in the diameter of the outer peripheral surface 12a of the rotary plate 12 is smaller than that of the ring. Since the amount of decrease in the diameter of the inner peripheral surface 13a of the ring-shaped magnet 13 is larger, the ring-shaped magnet 13 receives elastic force from the elastic holding member 12c and moves in the direction of increasing the diameter along the outer peripheral surface 12a of the rotary plate 12. To do. Therefore, in this case, there is no gap between the ring-shaped magnet 13 and the rotary plate 12, and the connected state between the ring-shaped magnet 13 and the rotary plate 12 is reliably maintained. Of course, no compressive stress is generated in the ring magnet 13.

Further, when the rotary plate 12 is not made of resin, the coefficient of thermal expansion of the rotary plate 12 may be smaller than the coefficient of thermal expansion of the ring-shaped magnet 13, and in this case, the above-described action is obtained. Conversely, as the temperature rises, the ring-shaped magnet 13 moves along the outer peripheral surface 12a of the rotating plate 12 in the direction of increasing diameter, and as the temperature falls, the ring-shaped magnet 13 rotates. It moves along the outer peripheral surface 12a of the plate 12 in the direction of decreasing the diameter.

According to the ring-shaped magnet fixing structure configured as described above, when the rotary plate 12 and the ring-shaped magnet 13 have different coefficients of thermal expansion, the diameter of the outer peripheral surface 12a of the rotary plate 12 and the diameter of the outer peripheral surface 12a of the rotary plate 12 are different due to the temperature difference. A difference occurs with the diameter of the inner peripheral surface 13a of the ring-shaped magnet 13, but this difference in diameter is absorbed by the ring-shaped magnet 13 moving on the outer peripheral surface 12 of the conical surface-shaped rotating plate 12. be able to. Therefore, the tensile stress or the compressive stress generated in the ring-shaped magnet 13 can be reduced. Therefore, the wall thickness of the ring-shaped magnet 13 is reduced by the amount corresponding to the reduction of these stresses. The strength of the magnet 13 can be reduced. That is, it is possible to reduce the dimensions such as the outer diameter of the ring-shaped magnet 13.

Although the elastic holding member 12c is formed integrally with the rotary plate 12 in the above embodiment, the elastic holding member 12c may be formed separately from the rotary plate 12. Needless to say. In that case, the elastic holding member 12c may be detachably provided on the rotating plate 12 with a screw or the like, or may be fixed to the rotating plate 12 by welding or the like. Further, it goes without saying that the rotary plate 12 is not limited to being formed of resin, and may be formed of metal or other material. Although the ring-shaped magnet 13 is shown as the ring-shaped member, it goes without saying that the ring-shaped member is not limited to the magnet.

Next, a second embodiment of the present invention will be described with reference to FIGS. However, elements common to the constituent elements shown in FIGS. 1 and 2 are designated by the same reference numerals, and description thereof will be omitted. The fixing structure of the ring-shaped member shown in FIGS. 5 and 6 is different from the fixing structure of the ring-shaped member shown in FIGS. 1 and 2 in the structures of the rotating plate and the ring-shaped magnet.

That is, as shown in FIGS. 5 and 6, the rotor 21 has a ring-shaped magnet (ring-shaped member) 23 on the outer periphery of a rotary plate (disc-shaped member) 22 having a rotation shaft 2 as a rotation center. It is fitted. The rotary plate 22 is made of a resin such as nylon or polyphenylene sulfide, and is formed into a disc shape. ing. The rotating plate 22 is formed with four arc-shaped elongated holes 22b along the outer peripheral surface 22a at regular intervals in the circumferential direction.

The long holes 22b penetrate the rotary plate 22 in the axial direction, and a connecting portion 22c for connecting the long holes 22b is formed between the long holes 22b and the long holes 22b. ing. The connecting portion 22c is inclined with respect to the normal line radiating from the axis of the rotating shaft 2, and the force of the spring is changed by changing the inclination angle with respect to the force acting on the outer peripheral surface 22a of the rotating plate 22. It is designed to work. The ring-shaped magnet 23 is magnetized into multiple poles at predetermined intervals in the circumferential direction, and its inner peripheral surface 23a is securely connected to the outer peripheral surface 22a of the rotary plate 22 by insert molding.

In the fixed structure of the ring-shaped member composed of the rotary plate 22 and the ring-shaped magnet 23 as described above, the connecting portion 22c is formed obliquely with respect to the normal line and functions as a spring. When the coefficient of thermal expansion of the rotary plate 22 is larger than that of the ring-shaped magnet 23, the increase in the diameter of the outer peripheral surface 22a of the rotary plate 22 is larger than that of the ring magnet 23 as the temperature rises from room temperature. The diameter is larger than the increase in the diameter of the inner peripheral surface 23a of the magnet 23 by, for example, a dimension dx, but the bending of the connecting portion 22c (that is, the inclination of the connecting portion 22c with respect to the normal line increases) Absorb the dimension dx. Therefore, almost no tensile stress is generated in the ring-shaped magnet 23.

When the temperature drops from room temperature, for example, when it is used in a cold region, the amount of decrease in the diameter of the outer peripheral surface 22 a of the rotary plate 22 is smaller than the inner circumference of the ring-shaped magnet 2. For example, the dimension dx 'becomes larger than the decrease in the diameter of the surface and a gap is about to be generated between the rotary plate 22 and the ring magnet 23, but the connecting portion 22c extends (that is, the connection with respect to the normal line). By reducing the inclination of the portion 22c), the diameter of the outer peripheral surface 22a increases by the dimension dx '. Therefore, there is no gap between the rotary plate 22 and the ring-shaped magnet 23, and the connected state of the rotary plate 22 and the ring-shaped magnet 23 is maintained.

Further, when the coefficient of thermal expansion of the rotary plate 22 is smaller than that of the ring-shaped magnet 23, the diameter of the outer peripheral surface 22a of the rotary plate 22 increases with increasing temperature, contrary to the above-described action. Is smaller than the increase in the diameter of the inner peripheral surface 23a of the ring-shaped magnet 23, the connecting portion 22c extends. Further, as the temperature decreases, the amount of decrease in the diameter of the outer peripheral surface 22a of the rotary plate 22 becomes smaller than the amount of decrease in the diameter of the inner peripheral surface 23a of the ring-shaped magnet 23, so that the connecting portion 22c bends.

According to the fixing structure of the ring-shaped magnet configured as described above, when the thermal expansion coefficient of the rotary plate 22 and the ring-shaped magnet 23 are different from each other, the diameter of the outer peripheral surface 22a of the rotary plate 22 and the diameter of the outer peripheral surface 22a of the rotary plate 22 are different due to the temperature difference. A difference occurs with the diameter of the inner peripheral surface 23a of the ring-shaped magnet 23, but this difference in diameter can be absorbed by the bending and extension of the connecting portion 22c. Therefore, the tensile stress or the compressive stress generated in the ring-shaped magnet 23 can be reduced, and the wall thickness of the ring-shaped magnet 23 can be reduced by an amount corresponding to the reduction of these stresses. The strength of can be reduced. That is, it is possible to reduce the outer diameter and other dimensions of the ring-shaped magnet 23.

In the above embodiment, the rotary plate 22 is configured to be integrally adhered to the ring-shaped magnet 23 by insert molding, but the ring-shaped magnet 23 is fixed to the rotary plate 22 by press fitting or the like. You may comprise. Further, it goes without saying that the rotary plate 22 is not limited to molding with resin, and may be formed with metal or other material. Further, although the ring-shaped magnet 23 is shown as the ring-shaped member, it goes without saying that the ring-shaped member is not limited to the magnet as long as it is a ring-shaped member.

[0033]

[Effect of the device]

 According to the invention described in claim 1, when the disc-shaped member and the ring-shaped member have different thermal expansion coefficients, a difference in temperature causes a difference between the outer diameter of the disc-shaped member and the inner diameter of the ring-shaped member. This difference in diameter can be absorbed by the ring-shaped member moving on the conical outer peripheral surface of the disc-shaped member. Therefore, it is possible to reduce the tensile stress or the compressive stress generated in the ring-shaped member. Therefore, the thickness of the ring-shaped member is reduced by the amount corresponding to the reduction of these stresses. The strength of can be reduced. That is, it is possible to reduce the dimensions such as the outer diameter of the ring-shaped member.

According to the second aspect of the invention, when the disc-shaped member and the ring-shaped member have different coefficients of thermal expansion, the outer diameter of the disc-shaped member and the inner diameter of the ring-shaped member are different due to the temperature difference. However, the difference in diameter can be absorbed by the bending and stretching of the connecting portion. Therefore, it is possible to reduce the tensile stress or the compressive stress generated in the ring-shaped member, and the thickness of the ring-shaped member is reduced by the amount corresponding to the reduction of these stresses to reduce the strength of the ring-shaped member. Reduction can be achieved. That is, it is possible to reduce the dimensions such as the outer diameter of the ring-shaped member.

[Brief description of drawings]

FIG. 1 is a plan view of a ring-shaped member fixing structure shown as a first embodiment of the present invention.

FIG. 2 is a sectional view showing a fixing structure of the ring-shaped member.

FIG. 3 is a sectional view of an essential part showing a fixing structure of the ring-shaped member.

FIG. 4 is a sectional view of an essential part showing the action of the fixing structure of the ring-shaped member.

FIG. 5 is a plan view of a ring-shaped member fixing structure shown as a second embodiment of the present invention.

FIG. 6 is a sectional view showing a fixing structure of the ring-shaped member.

FIG. 7 is a plan view of a ring-shaped member fixing structure shown as a conventional example.

FIG. 8 is a sectional view showing a fixing structure of the ring-shaped member.

FIG. 9 is a sectional view of an essential part showing a fixing structure of the ring-shaped member.

FIG. 10 is a sectional view of an essential part showing another example of the fixing structure of the ring-shaped member.

[Explanation of symbols]

 12, 22 Disc-shaped member (rotating plate) 12a, 22a Outer peripheral surface 12c Elastic holding member 13, 23 Ring-shaped member (ring-shaped magnet) 13a, 23a Inner peripheral surface 22b Hole (long hole) 22c Connection portion

Claims (2)

[Scope of utility model registration request] 1. A ring-shaped member fixing structure for fixing a ring-shaped member to the disk-shaped member by fitting the ring-shaped member on the outer peripheral surface of the disk-shaped member, The outer peripheral surface of the member and the inner peripheral surface of the ring-shaped member fitted to the outer peripheral surface are formed in a conical surface shape with the axis of the disc-shaped member as the center line, and the disc-shaped member has the ring. A fixing structure for a ring-shaped member, characterized in that an elastic holding member is provided to generate an elastic force so as to prevent the cylindrical member from moving along the outer peripheral surface in the direction of decreasing the diameter. 2. A ring-shaped member fixing structure for fixing the ring-shaped member to the disk-shaped member by fitting the ring-shaped member on the outer peripheral surface of the disk-shaped member. A plurality of holes penetrating in the axial direction are provided at predetermined intervals in the circumferential direction in the member, and a connecting portion connecting these adjacent holes to each other is formed in a radial direction from the axis of the disc-shaped member. A fixing structure for a ring-shaped member, which is formed obliquely with respect to an extending normal line.