JP6490638B2 - Position control structure of rotating shaft - Google Patents

Description

  The present invention is applied to a transmission or the like mounted on a vehicle, and relates to a structure that regulates the position of a rotation shaft in the rotation axis direction.

  In a vehicle equipped with an automatic transmission, the torque generated by the engine is input to the automatic transmission via a torque converter, and the driving force changed by the automatic transmission is transmitted to the drive wheels. For example, a continuously variable transmission (CVT) or a stepped automatic transmission (AT) is widely used as the automatic transmission.

  In an automatic transmission, a brake for braking the rotating element, a clutch for connecting the rotating element and another rotating element, and the like are often used. It is necessary to supply oil for operating brakes, clutches, and torque converters. Therefore, in the automatic transmission, the hydraulic pressure generated by the oil pump is regulated by the valve body, and the regulated hydraulic pressure is supplied from the valve body to each part that needs to supply oil through the oil passage.

  The oil pump includes a pump drive shaft, a pump housing, and a pump gear. The pump drive shaft passes through the pump housing so as to be relatively rotatable. The pump gear is accommodated in the pump housing. A spline is formed on the peripheral surface of the pump drive shaft at a portion disposed in the pump housing. When the spline formed on the pump gear meshes with the spline, the pump drive shaft and the pump gear cannot be rotated relative to each other. Are splined together.

Japanese Patent Laying-Open No. 2015-145682

  As a configuration that regulates the position of the pump drive shaft in the rotation axis direction, for example, a circumferential groove is formed in a splined up part of the pump drive shaft, and a snap ring is attached to the groove, and the snap ring and pump gear The structure which contacts can be considered. However, since the configuration requires a snap ring, the cost is increased, and the pump drive shaft must be inserted into the pump housing after the pump gear and the snap ring are attached to the pump drive shaft, which limits the assembly order. End up.

  The objective of this invention is providing the position control structure of a rotating shaft which can control the position of the rotating shaft direction of a rotating shaft, without using a snap ring.

  In order to achieve the above object, the rotational shaft position restricting structure according to the present invention is the rotation of the rotational shaft inserted or inserted in the rotational axis direction into the first member and the second member provided side by side in the rotational axis direction. The position is controlled in the axial direction, and oil is supplied between the first member and the rotary shaft and between the second member and the rotary shaft, and the rotary shaft is driven by the oil pressure of the supplied oil. The shape of the peripheral surface of the rotating shaft is designed so that a force toward one side in the rotating axis direction is generated.

  According to this configuration, the rotation shaft is inserted or inserted into the first member and the second member provided side by side in the rotation axis direction. Oil (hydraulic pressure) is supplied between the first member and the rotation shaft and between the second member and the rotation shaft, respectively. Therefore, the oil pressure supplied between the first member and the rotating shaft and the oil pressure supplied between the second member and the rotating shaft act on the peripheral surface of the rotating shaft.

  In a configuration in which a step is formed on the peripheral surface of the rotation shaft, a surface intersecting the rotation axis direction exists at the step portion, and the hydraulic pressure acting on the surface has a component in the rotation axis direction. Therefore, by considering the oil pressure supplied between the first member and the rotating shaft and between the second member and the rotating shaft, by designing the shape (step) of the peripheral surface of the rotating shaft, A force directed to one side in the rotation axis direction can be generated on the rotation shaft.

  Regulating that the rotation axis is shifted to the other side in the rotation axis direction without using a snap ring when the force applied to the rotation axis toward the one side in the rotation axis direction is generated by the hydraulic pressure applied to the peripheral surface of the rotation shaft. Since the position of the rotating shaft can be regulated in the direction of the rotating axis, the cost can be reduced and the degree of freedom in assembling the rotating shaft can be improved.

  The shape of the peripheral surface of the rotating shaft includes not only the shape of the peripheral surface itself but also the shape of a member provided integrally with the rotating shaft.

  An oil pump may be disposed on the other side of the rotation axis direction with respect to the rotation shaft, and the rotation shaft may be a pump drive shaft provided in the oil pump. In this case, the position of the pump drive shaft in the rotational axis direction can be regulated (suppressing displacement to the oil pump side) without using a snap ring, and costs can be reduced and the degree of freedom of assembly of the oil pump can be improved. .

  According to the present invention, since the position of the rotation axis in the direction of the rotation axis can be regulated without using a snap ring, the cost can be reduced and the degree of freedom of assembly of the rotation axis can be improved.

It is sectional drawing which shows a part of transmission unit to which the position control structure which concerns on one Embodiment of this invention was applied. It is sectional drawing which shows the shape of the one end part of a pump drive shaft. It is sectional drawing which shows the shape of the other end part of a pump drive shaft.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

<Configuration of transmission unit>
FIG. 1 is a cross-sectional view showing a part of a transmission unit 1 to which a position restricting structure according to an embodiment of the present invention is applied. In addition, in each figure including FIG. 1, the provision of hatching indicating a cross section is omitted.

  The transmission unit 1 is a unit that is mounted on a vehicle, changes the torque generated by an engine (not shown), and transmits the torque to drive wheels (not shown), and includes a torque converter 2 and an automatic transmission 3.

  The torque converter 2 includes a front cover 11, a pump impeller 12, a turbine runner 13, a lockup clutch 14, and a stator 15.

  The front cover 11 extends in a substantially disk shape around the rotation axis. The front cover 11 receives engine generated torque (engine torque). A center piece 16 is formed at the center of the front cover 11 by the front cover 11 bulging in a cylindrical shape toward the engine side (the right side in FIG. 1, hereinafter referred to as “right side”). A relatively thick cylindrical bearing member 17 is provided integrally with the center piece 16 inside the center piece 16.

  The pump impeller 12 is disposed on the side opposite to the engine side with respect to the front cover 11 (left side in FIG. 1, hereinafter referred to as “left side”). The pump impeller 12 is provided so as to be able to rotate integrally with the front cover 11.

  The turbine runner 13 is disposed between the front cover 11 and the pump impeller 12 and is provided so as to be rotatable about a rotation axis.

  The lockup clutch 14 is disposed between the front cover 11 and the turbine runner 13. The lockup clutch 14 is engaged by a hydraulic pressure difference between the release side oil chamber 18 between the lockup clutch 14 and the front cover 11 and the engagement side oil chamber 19 between the lockup clutch 14 and the pump impeller 12. Combined / released.

  The stator 15 is disposed between the pump impeller 12 and the turbine runner 13.

  The automatic transmission 3 includes an input shaft 21.

  The input shaft 21 extends on the rotation axis. A right end portion of the input shaft 21 is inserted into the torque converter 2. The turbine runner 13 of the torque converter 2 is spline-coupled to the input shaft 21 and is supported on the input shaft 21 so as not to be relatively rotatable.

  The outer periphery of the input shaft 21 is surrounded by a substantially cylindrical stator shaft 22. A gap 23 is provided between the input shaft 21 and the stator shaft 22. The right end of the stator shaft 22 is inserted into the torque converter 2. The stator 15 of the torque converter 2 is supported at the right end of the stator shaft 22 (via a one-way clutch). A space is provided between the stator shaft 22 and the turbine runner 13, and a gap 23 between the input shaft 21 and the stator shaft 22 is engaged via the stator shaft 22 and the turbine runner 13. It communicates with the side oil chamber 19.

  The oil pump 4 is disposed on the left side of the input shaft 21. The oil pump 4 includes a pump housing 31, a pump drive shaft 32, and a pump gear 33.

  The pump drive shaft 32 extends along the rotational axis and is inserted into the input shaft 21. A spline 34 is formed on the outer peripheral surface of the right end portion of the pump drive shaft 32. Then, the right end portion of the pump drive shaft 32 is inserted into the bearing member 17, and the spline 34 and the spline 35 formed on the inner peripheral surface of the bearing member 17 are engaged with each other, thereby being splined with the bearing member 17. ing. A gap is provided between the inner peripheral surface of the input shaft 21 and the outer peripheral surface of the pump drive shaft 32, and an inter-shaft oil passage 36 is formed by the gap. The left end of the inter-shaft oil passage 36 is closed by a seal 37 interposed between the inner peripheral surface of the input shaft 21 and the outer peripheral surface of the pump drive shaft 32, and the right end thereof is open. Thus, the inter-shaft oil passage 36 communicates with the release-side oil chamber 18 between the lockup clutch 14 and the front cover 11.

  The left end of the pump drive shaft 32 is inserted into the pump housing 31.

  The pump gear 33 is accommodated in the pump housing 31 and is spline-coupled to the pump drive shaft 32 so as to be integrally rotatable. Thus, when the front cover 11 of the torque converter 2 rotates, the pump drive shaft 32 rotates and the pump gear 33 rotates integrally with the pump drive shaft 32. As the pump gear 33 rotates, the oil pump 4 generates hydraulic pressure (line pressure PL), and the hydraulic pressure is supplied to a valve body (not shown).

  On the left and right sides of the pump gear 33, seals 38 and 39 are provided that support the pump drive shaft 32 by the pump housing 31 and seal between the pump housing 31 and the pump drive shaft 32.

  The pump housing 31 is formed with a supply oil passage 41 through which oil (hydraulic pressure) is supplied from the valve body. An axial oil passage 42 is formed in the pump drive shaft 32. The shaft center oil passage 42 is opened at the left end of the pump drive shaft 32 and communicates with the supply oil passage 41. Further, the shaft center oil passage 42 communicates with an inter-shaft oil passage 36 between the input shaft 21 and the pump drive shaft 32 via a communication oil passage 43 formed in the pump drive shaft 32. As a result, oil pressure can be supplied from the supply oil passage 41 to the inter-shaft oil passage 36 between the input shaft 21 and the pump drive shaft 32 through the shaft center oil passage 42 and the communication oil passage 43. The operating pressure Ps can be supplied to the release-side oil chamber 18 of the torque converter 2 through the intermediate oil passage 36. The operating pressure Ps is generated, for example, by adjusting the line pressure PL with a linear solenoid valve provided in the valve body.

<Shape of pump drive shaft>
2A and 2B are cross-sectional views showing the shape of the pump drive shaft 32.

  As shown in FIG. 2A, the pump drive shaft 32 has a minimum diameter Ds <b> 1 and a maximum diameter DL in a portion accommodated in the pump housing 31.

  A seal 37 interposed between the inner peripheral surface of the input shaft 21 and the outer peripheral surface of the pump drive shaft 32 is fitted into a seal groove 51 formed on the outer peripheral surface of the pump drive shaft 32, The end is in liquid-tight contact with the inner peripheral surface of the input shaft 21. The outer diameter Ds2 of the seal 37 is the same as the diameter of the inner peripheral surface of the input shaft 21.

  As described above, when the operating pressure Ps is supplied to the supply oil passage 41, the operating pressure Ps passes through the shaft center oil passage 42, the communication oil passage 43, and the inter-shaft oil passage 36 in order to release the torque converter 2. The oil is supplied to the side oil chamber 18. 2A and 2B, the portion on the left side of the seal 38 in the pump housing 31, the release side oil chamber 18, the inter-shaft oil passage 36, the shaft center oil passage 42, the communication oil, The space between the path 43 and the right end portion of the pump drive shaft 32 and the front cover 11 (center piece 16) and the bearing member 17 are filled with oil of the operating pressure Ps.

  On the other hand, oil of the line pressure PL generated by the oil pump 4 flows between the seals 38 and 39 in the pump housing 31 as shown by the right-down hatching in FIG. 2A.

  The shape of the peripheral surface of the pump drive shaft 32, specifically, the diameters Ds1, DL of the pump drive shaft 32 and the outer diameter Ds2 of the seal 37 are designed to satisfy the following inequality.

As1 × Ps + (AL−As1) × PL> As2 × Ps (formula)
As1 × Ps + (AL−As1) × PL: force pushing the pump drive shaft 32 to the right As2 × Ps: force pushing the pump drive shaft 32 to the left As1 = π × Ds1 ^ 2/4
As2 = π × Ds2 ^ 2/4
AL = π × DL ^ 2/4

  As a result, the pump drive shaft 32 is pushed to the right side by the hydraulic pressure, and the right end of the pump drive shaft 32 comes into contact with the front cover 11 (center piece 16) and is positioned in the rotational axis direction. When the pump drive shaft 32 is pushed to the left side and its left end is pushed against the pump housing 31, relative rotation occurs between the pump housing 31 and the pump drive shaft 32, and there is a possibility of causing wear or the like. Since the pump drive shaft 32 is pressed against the front cover 11 that rotates integrally with the pump drive shaft 32, no relative rotation occurs between the pump drive shaft 32 and the front cover 11. be able to.

<Effect>
In this way, when the pump drive shaft 32 is pushed to the right side by hydraulic pressure, it is possible to restrict the pump drive shaft 32 from shifting to the left without using a snap ring, and the pump drive shaft 32 comes into contact with the front cover 11. It is also possible to regulate the shift to the right side. That is, the position of the pump drive shaft 32 in the rotational axis direction can be regulated without using a snap ring. Therefore, the cost can be reduced and the degree of freedom in assembling the oil pump 4 can be improved.

  Further, as the generated hydraulic pressure (line pressure PL) of the oil pump 4 rises, the pump drive shaft 32 is pushed to the right side by the hydraulic pressure of the oil flowing into the seals 38 and 39, so that immediately after the oil pump 4 is started (the engine of the vehicle) The position in the rotational axis direction of the pump drive shaft 32 can be regulated from immediately after the start.

<Modification>
As mentioned above, although one Embodiment of this invention was described, this invention can also be implemented with another form.

  For example, in the above-described embodiment, the structure that regulates the position of the pump drive shaft 32 in the rotation axis direction has been taken up. However, the present invention is not limited to the pump drive shaft 32 provided in the transmission unit 1, for example, The present invention can also be applied to a structure that regulates the position in the rotation axis direction such as an output shaft.

  In addition, various design changes can be made to the above-described configuration within the scope of the matters described in the claims.

21: Input shaft (first member)
31: Pump housing (second member)
32: Pump drive shaft (rotating shaft)

Claims (1)

A structure that regulates a position of the rotary shaft that is inserted or inserted in the rotary axis direction into a first member and a second member that are provided side by side in the rotary axis direction;
Oil is supplied between the first member and the rotating shaft and between the second member and the rotating shaft,
The shape of the peripheral surface of the rotating shaft is designed so that a force directed to one side of the rotating shaft direction is generated on the rotating shaft by the oil pressure of the supplied oil,
On the other side of the rotation axis direction with respect to the rotation axis, an oil pump that generates hydraulic pressure is disposed,
The second member is a pump housing provided in the oil pump;
The rotation shaft is a pump drive shaft provided in the oil pump, and is pressed against a front cover of a torque converter that rotates integrally with the rotation shaft by a force toward one side in the rotation axis direction. Construction.

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