JP2006275106A - Shaft holding member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shaft holding member capable of attaching and smoothly rotating a shaft body having a non-circular cross section without affecting a bearing.
A shaft holding portion 14a that externally holds a shaft body 12 having a non-circular cross section and a bearing mounting portion 14b that is attached to a bearing 13 are provided at different positions along the direction of the rotation axis. According to this configuration, since the shaft holding portion and the bearing mounting portion are provided at different positions, no pressure is applied to the shaft body at the bearing mounting portion, and the outer peripheral shape is not easily deformed. Therefore, any shaft body having any cross-sectional shape can be attached without affecting the bearing, and the shaft body can be smoothly rotated.
[Selection] Figure 2

Description

  The present invention relates to a shaft holding member that externally holds a shaft body having a non-circular cross section and is attached to a bearing.

  Conventionally, in order to rotatably mount a shaft body having a non-circular cross section, for example, to a bearing such as a ball bearing, a shaft holding member capable of externally holding the shaft body is provided, and this is press-fitted into the inner ring of the bearing. Then, the shaft body is press-fitted into the shaft holding member.

For example, a variable intake valve (see, for example, Patent Document 1) provided in an intake manifold of an automobile engine is known as an application of this type of shaft holding member. This variable intake valve is provided so that the intake path of the engine can be switched by opening and closing, and the intake pipe length is changed according to the engine speed to improve the intake efficiency of the engine. Normally, when the engine speed is low, the short intake path of the two long and short intake paths is closed to increase the intake pipe length, and when the engine speed increases, both intake paths are opened to shorten the intake pipe length.
As another variable intake valve, there is also known an airflow control valve that is provided in the vicinity of a cylinder head of an engine and that improves combustion by changing the flow path area by opening and closing the variable intake valve.

  Such a variable intake valve is arranged in the intake pipe so as to prevent intake when closed, and is opened by tilting the valve body of the variable intake valve so as to be parallel to the intake direction. For this reason, it is necessary to make the variable intake valve as thin as possible so as not to hinder the flow as much as possible during intake, and the shaft body that supports the valve body of the variable intake valve may have a rectangular cross section. desirable.

JP 2002-317718 A

  However, the conventional shaft holding member has a hole portion that externally holds the shaft body on the inner peripheral surface, and is provided on the outer peripheral surface so as to be supported by the bearing. For this reason, when a shaft body having a rectangular cross section is press-fitted into the shaft holding member press-fitted into the bearing as described above, the outer peripheral shape of the shaft holding member is not applied to the outer peripheral surface of the shaft holding member. There was a problem that was not completely circular.

In such a shaft holding member, even the inner ring of the bearing is deformed when the shaft body is press-fitted, and the radial gap becomes non-uniform, so that the inner ring does not rotate smoothly with respect to the outer ring, and the wear of the bearing is promoted. Let And this tendency becomes so large that a shaft is made flat.
Such a problem is not limited to the case where the shaft holding member is press-fitted into the inner ring of the bearing and rotated with respect to the outer ring of the bearing, but the case where the shaft holding member slides and rotates with respect to the bearing. This is the same because the outer peripheral shape of the shaft holding member is not a perfect circle.

  For this problem, attempts have been made to increase the distance between the shaft body and the bearing in order to reduce the influence on the bearing of the shape of the shaft body, but in order to completely eliminate the influence on the bearing. However, another problem that the apparatus becomes larger has occurred.

  The present invention has been made in view of the above-described problems, and provides a shaft holding member capable of attaching and smoothly rotating a shaft body having a non-circular cross section without affecting the bearing. Objective.

  The first characteristic configuration of the shaft holding member according to the present invention for achieving the above object is to rotate a shaft holding portion that externally holds a shaft body having a non-circular cross section and a bearing mounting portion that is attached to the bearing. It exists in the point provided in the different position along the direction of an axial center.

  That is, according to this configuration, since the shaft holding portion and the bearing mounting portion are provided at different positions, the shaft mounting pressure is not applied to the bearing mounting portion, and the outer peripheral shape is not easily deformed. Therefore, any shaft body having any cross-sectional shape can be attached without affecting the bearing, and the shaft body can be smoothly rotated.

  A second characteristic configuration of the shaft holding member according to the present invention is that the bearing mounting portion is formed in a hollow shape through which the shaft body can be inserted.

  That is, according to this structure, since the shaft mounting body is provided so that the shaft body can be inserted, the shaft body can be passed through the bearing without affecting the bearing.

  A third characteristic configuration of the shaft holding member according to the present invention is that the bearing mounting portion is formed solid.

That is, according to this configuration, since the shaft body can be held only on the shaft body side with respect to the bearing, it can be installed without considering the space of the mounting location.
Further, since the bearing mounting portion is formed solid, sufficient strength can be obtained for the bearing.

  A fourth characteristic configuration of the shaft holding member according to the present invention is that a second shaft holding portion for holding the shaft body is provided at a position opposite to the shaft holding portion with respect to the bearing mounting portion. .

  That is, according to this configuration, even when the shaft body cannot be held only by the shaft holding portion, a sufficient holding force can be obtained by providing the second shaft holding portion.

  A fifth characteristic configuration of the shaft holding member according to the present invention is that a pressing member that presses the shaft holding portion toward the shaft body is provided on the outer surface of the shaft holding portion.

  That is, according to this configuration, the holding force of the shaft body in the shaft holding portion can be increased.

  The shaft holding member according to the present invention includes a shaft holding portion that externally holds a shaft body having a non-circular cross section and a bearing mounting portion that is attached to the bearing at different positions along the direction of the rotation axis. Is. With such a shaft holding member, it is possible to install a shaft body having any cross-sectional shape without affecting the bearing.

[First embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. Here, the case where the present invention is applied to the variable intake valve 1 of the intake system of the engine as shown in FIG. 1 will be described as an example.

An intake manifold 2 to which the variable intake valve 1 according to the present embodiment is applied is connected to a cylinder 4 provided with a piston 3 at one end via an intake valve 5, and the cylinder 4 is connected via an exhaust valve 6. The exhaust manifold 7 is connected. Further, air can be supplied to the cylinder 4 via the intake manifold 2, and the variable intake valve 1 is provided in the middle of the intake manifold 2 (near the combustion chamber).
The variable intake valve 1 is an airflow control valve that adjusts the flow velocity by changing the passage cross section of the air flowing through the intake manifold 2. Thereby, the combustion improvement of an engine can be aimed at.

As shown in FIG. 2, such a variable intake valve 1 includes a valve body 11 that changes an air passage section, a shaft body 12 that supports the valve body 11, and a bearing 13 that supports the valve body so as to be freely opened and closed. The shaft body 12 is externally fitted and held and a shaft holding member 14 that can be attached to the bearing 13 is provided. These can be mounted by, for example, providing the shaft holding member 14 with a sintered alloy, press-fitting the shaft holding member 14 into the bearing 13, and then press-fitting the shaft body 12 into the shaft holding member 14. The bearing 13 is, for example, a ball bearing in which the inner ring is rotatable with respect to the outer ring. In this case, the shaft holding member 14 is press-fitted into the inner ring.
The shaft body 12 has a rectangular cross section, and is attached to the valve body 11 so that its long side is on the valve body 11 side, and the intake air flow when the variable intake valve 1 is opened. It is configured not to disturb.
Moreover, although the valve body 11 is eccentrically and axially supported, not only this but a conventionally well-known shape is applicable.

  As shown in FIG. 3, the shaft holding member 14 is provided with a shaft holding portion 14 a that externally holds the shaft body 12 and a bearing mounting portion 14 b that is attached to the bearing 13 at different positions along the direction of the rotation axis. is there.

The shaft holding portion 14a has a hole having a rectangular cross section in accordance with the shape of the shaft body 12, and the shaft body 12 can be press-fitted. Further, the outer peripheral shape of the shaft holding portion 14a is not particularly limited, but is provided in a cylindrical shape in the present embodiment.
The bearing mounting portion 14b is formed in a cylindrical shape so that its outer periphery can be fitted and fitted to the inner ring of the bearing 13, and the inside thereof is formed hollow so that the shaft body 12 can be inserted. By forming the bearing mounting portion 14b hollow in this way, the shaft body can be passed through the bearing without affecting the bearing. For example, a sensor or the like can be provided at the end of the shaft body 12. . The hollow shape is not limited to the circular shape as in this embodiment, and any shape can be selected as long as no pressure is applied when the shaft body 12 is press-fitted.

With such a configuration, even if the shaft body 12 is press-fitted in the bearing mounting portion 14b, the pressure is not applied, so that the outer peripheral shape can be easily kept circular. As a result, the shape of the inner ring of the bearing 13 can be kept substantially circular without being deformed, and can be smoothly rotated with respect to the outer ring.
Since the shaft body 12, the shaft holding member 14, and the bearing 13 can be press-fitted and configured, backlash in the thrust direction can also be restricted.
For this reason, in the variable intake valve 1, it is possible to apply the shaft body 12 in which the projected area of the intake air flow when the valve is opened is minimized.

  In the present embodiment, the effect of the shaft holding member 14 according to the present invention has been described using a ball bearing as an example of the bearing 13, but the bearing 13 that rotates the shaft holding member 14 by sliding contact is also described above. Since the outer peripheral shape of the bearing mounting portion 14b can be kept substantially circular, the same effect can be obtained.

[Second Embodiment]
Next, a second embodiment according to the present invention will be described. In the shaft holding member 14 according to the present embodiment, as shown in FIG. 4, the shaft holding width in the axial center direction of the shaft holding portion 14a is small, and is opposite to the shaft holding portion 14a with respect to the bearing mounting portion 14b. A second shaft holding member 15 for assisting the holding of the shaft body 12 is provided at a position on the side to constitute a second holding portion. Other configurations are the same as those of the first embodiment.

The outer periphery of the second shaft holding member 15 is provided in the hollow shape of the shaft holding member 14 and a cylindrical shape that can be press-fitted, and a hole portion through which the shaft body 12 can be press-fitted is provided. The second shaft holding member 15 can be made of the same material as the shaft holding member 14 and a sintered alloy.
In the present embodiment, the single second shaft holding member 15 that is externally fitted to the shaft body 12 is illustrated. However, the shaft body 12 is sandwiched between the two second shaft holding members 15. May be.

  With such a configuration, even if a large space cannot be taken on the opposite side of the valve body 11 with respect to the bearing 13 and a sufficient holding force cannot be obtained only by the shaft holding portion 14a, a sufficient holding force can be obtained. Can be demonstrated.

[Third embodiment]
Next, a third embodiment according to the present invention will be described. In the shaft holding member 14 according to the present embodiment, the bearing mounting portion 14 is solidly formed as shown in FIG. 5, and the end portion of the shaft body 12 and the shaft body 12 are held on the shaft body 12 side with respect to the bearing 13. To do. The shaft holding portion 14a has a hole having a rectangular cross section in accordance with the shape of the shaft body 12, and the shaft body 12 can be press-fitted. Other configurations are the same as those in the first embodiment.

  With such a configuration, for example, even when there is almost no space on the opposite side of the valve body 11 with respect to the bearing 13, the bearing 13 can be attached. Further, since the bearing mounting portion 13b is formed solid, sufficient strength can be ensured with respect to the bearing 13.

[Fourth embodiment]
Next, a fourth embodiment according to the present invention will be described. In the shaft holding member 14 according to the present embodiment, as shown in FIG. 6, the bearing mounting portion 14 is solidly formed as in the third embodiment. The shaft holding portion 14a is provided so that the shaft body 12 can be clamped, and a cylindrical pressing member 16 that presses against the shaft body 12 side is press-fitted to the outer surface of the shaft holding portion 14a to supplement the holding force of the shaft body 12. It is provided. Further, the shaft holding portion 14a is provided with a widened portion 17 that is a relief portion that does not come into contact with the end portion of the shaft body 12. When the shaft body 12 is inserted into the shaft holding portion 14a, stress is concentrated on the corner portion. Thus, it is configured not to crack. Other configurations are the same as those in the first embodiment.

In the present embodiment, the pressing member 16 is described as an example of a cylindrical shape. However, the pressing member 16 is not limited to this, and may be fastened with a band member or the like, or may be sandwiched, and the material is also particularly limited. There is no.
Moreover, although the expansion part 17 showed the example which provided the two groove parts so that it might not contact | abut the edge part of the shaft body 12, it is not restricted to this, For example, the surface facing the end surface of the shaft body 12 is shown. A concave curved surface may be provided as one groove.

[Other Embodiments]
In the first embodiment and the second embodiment, the example in which the bearing mounting portion 14b is provided in the hollow and the shaft body 12 is penetrated is shown. However, the present invention is not limited to this. For example, as shown in FIG. The end of the body 12 can also be supported.

  In each said embodiment, although the case where the cross section of the shaft 12 was made into the rectangular shape was shown as an example, not only this but a square, an ellipse, and another polygon may be sufficient.

  In each said embodiment, although the case where the shaft holding member 14 was provided with the sintered alloy was shown as an example, it is not restricted to this, For example, cheap materials, such as a cold forging material, can also be applied.

  In each of the above-described embodiments, the shaft holding member 14 according to the present invention is applied to an airflow control valve that adjusts the flow velocity by changing the passage cross section of the air flowing through the intake manifold 2 as the variable intake valve 1 of the automobile. However, the present invention can be applied to a variable intake valve 1 whose length is changed to an intake pipe as shown in FIG. In other words, the intake manifold 2 to which the variable intake valve 1 is applied is connected to the air distribution chamber 8 so that air can be supplied to the cylinder 4 via the intake manifold 2. A branch pipe 9 connected to the air distribution chamber 8 is provided in the middle of the intake manifold 2, and a variable intake valve 1 is provided at the inlet of the branch pipe 9 so as to prevent intake from the branch pipe. .

  The variable intake valve 1 opens and closes according to the engine speed, thereby substantially changing the length of the intake pipe and improving the intake efficiency. Normally, the intake pipe length is lengthened when the engine speed is low, and the intake pipe length is shortened when the engine speed is high. Therefore, when the engine speed is low, the variable intake valve 1 is closed to intake air (solid arrow), and when the engine speed is high, the variable intake valve 1 is opened to allow intake from the branch pipe 9 as well. (Dashed arrow). Thereby, air can be efficiently supplied in a wide range of engine speeds.

  Furthermore, the shaft holding member 14 according to the present invention is not limited to the application example of the above-described embodiment, and can be applied to all uses in the case where the shaft body 12 has a non-circular cross section.

The figure which shows the example of application of the shaft holding member which concerns on 1st embodiment of this invention. The figure explaining the variable intake valve to which the shaft holding member which concerns on 1st embodiment of this invention is applied. Sectional drawing which shows the shaft holding member which concerns on 1st embodiment of this invention. Sectional drawing which shows the shaft holding member which concerns on 2nd embodiment of this invention. Sectional drawing which shows the shaft holding member which concerns on 3rd embodiment of this invention. Sectional drawing which shows the shaft holding member which concerns on 4th embodiment of this invention. Sectional drawing which shows the shaft holding member which concerns on other embodiment of this invention. The figure which shows the other example of application of the shaft holding member which concerns on this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Variable intake valve 2 Intake manifold 12 Shaft body 13 Bearing 14 Shaft holding member 14a Shaft holding portion 14b Bearing mounting portion 15 Second shaft holding member 16 Pressing member

Claims (5)

  A shaft holding member in which a shaft holding portion that externally holds a shaft body having a non-circular cross section and a bearing mounting portion that is attached to the bearing are provided at different positions along the direction of the rotation axis.   The shaft holding member according to claim 1, wherein the bearing mounting portion is formed in a hollow shape through which the shaft body can be inserted.   The shaft holding member according to claim 1, wherein the bearing mounting portion is formed solid.   The shaft holding member according to claim 2, wherein a second shaft holding portion that holds the shaft body is provided at a position opposite to the shaft holding portion with respect to the bearing mounting portion.   The shaft holding member according to any one of claims 1 to 4, wherein a pressing member that presses the shaft holding portion toward the shaft body is provided on an outer surface of the shaft holding portion.

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