JP2016109146A - Two-stage transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a two-stage transmission capable of realizing simplification of a structure in addition to reduction of a size and a weight.SOLUTION: A two-stage transmission includes a planetary gear mechanism 10 including an input shaft 2 to which rotation output is given, an output shaft 3, a sun gear 11 formed on the input shaft 2, an annular gear 12 disposed around the sun gear 11, a planetary gear 13 engaged with both of the sun gear 11 and the annular gear 12, and a carrier 14 lowering the rotation output given to the input shaft 2 by rotatably supporting the planetary gear 13 fixed to the output shaft 3, and outputting the same. A clutch mechanism 20 is disposed to switch a low-speed mode for keeping the annular gear 12 of the planetary gear mechanism 10 in a fixed state, lowering the rotation output given to the input shaft 2 by the planetary gear mechanism 10, and outputting the same to the output shaft 3, and a high-speed mode for outputting the rotation output given to the input shaft 2 to the output shaft 3 as it is through the carrier 14 of the planetary gear mechanism 10.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a two-stage transmission that is mounted on, for example, an electric vehicle and outputs a rotational force input from a motor by switching between two stages of a high speed mode and a low speed mode.

  Conventionally, as the above-described two-stage transmission, for example, there is one described in Patent Document 1, and this two-stage transmission includes an input shaft connected to a motor, an output shaft, an input shaft, and an output. A planetary gear mechanism connected to both of the shafts is provided.

  The planetary gear mechanism includes a sun gear fixed to the input shaft, an annular gear arranged around the sun gear, a planetary gear meshing with both the sun gear and the annular gear, and the planetary gear rotatably supported. By doing so, a carrier is provided that outputs the rotational output from the motor applied to the input shaft.

  Further, in this two-stage transmission, a clutch mechanism that selects a carrier rotating with respect to the annular gear and an input shaft and connects it to the output shaft after the annular gear of the planetary gear mechanism is fixed. I have.

  This clutch mechanism is formed on a carrier that is formed on a carrier that rotates with respect to an annular gear and is fitted to an input shaft, and is fitted inside the cylinder of the carrier so as to be rotatable on the input shaft and movable in the axial direction. A sleeve that is axially movable and non-rotatably fitted to the output shaft, a torque transmitting ball held on a portion of the sleeve fitted to the input shaft, and a carrier cylinder And an input shaft that is formed to be axially shifted from each other, engages with a torque transmission ball of the sleeve and transmits each rotation to the sleeve, and a torque transmission ball held by the sleeve is a carrier. And a drive section for moving the sleeve between a position where it engages with the engaging section and a position where it engages with the engaging section of the input shaft.

  In this two-stage transmission, the sleeve is moved in the axial direction by the driving portion of the clutch mechanism, and the torque transmission ball held by the sleeve is engaged with the engaging portion of the input shaft, thereby being applied to the input shaft. The rotation output from the motor is transmitted to the output shaft as it is, while the sleeve is moved in the axial direction by the driving portion of the clutch mechanism, and the torque transmission ball held by the sleeve is rotated with respect to the annular gear. By engaging with the engaging portion of the carrier, the planetary gear mechanism is operated, and the rotational output from the motor is reduced in speed and transmitted to the output shaft.

  Thus, in this two-stage transmission, the high-speed rotation output that is not decelerated and the low-speed rotation output that is decelerated are selectively switched by one clutch mechanism and output to the output shaft. Therefore, the size and weight can be reduced by the amount that does not require a plurality of friction clutches.

JP 2011-220484 A

  However, in the conventional two-stage transmission described above, a heavy friction clutch is used to select and transmit either the undecelerated high-speed rotation output or the decelerated low-speed rotation output to the output shaft. Therefore, although the size and weight can be reduced by that much, the clutch mechanism is structured so that the torque transmission ball held by the sleeve engages with the carrier engaging portion and the input shaft engaging portion. Since the structure in which the sleeve is moved in the axial direction between the engagement position and the engagement position is employed, it is difficult to say that the structure of the clutch mechanism is simple. It was an issue.

  The present invention has been made paying attention to the above-described conventional problems, and an object thereof is to provide a two-stage transmission capable of realizing a simplified structure in addition to a reduction in size and weight.

  A first aspect of the present invention includes an input shaft, an output shaft, a sun gear that rotates coaxially with the input shaft, an annular gear disposed around the sun gear, and both the sun gear and the annular gear. A planetary gear mechanism having a meshing planetary gear and a carrier fixed to the output shaft and rotatably supporting the planetary gear to reduce the rotational output applied to the input shaft and outputting the planetary gear. A low-speed mode in which an annular gear of the mechanism is fixed, a rotation output applied to the input shaft is dropped by the planetary gear mechanism and output to the output shaft, and a rotation output applied to the input shaft is output to the planetary gear mechanism A clutch mechanism for switching between a high-speed mode in which the output is output to the output shaft as it is via the carrier is provided.

  In the second aspect of the present invention, the clutch mechanism may include a slide cylinder that is axially movable and non-rotatably fitted to the input shaft, and a slide cylinder that is fitted to the input shaft. The cylinder-side engaging portion that is arranged and the carrier that rotatably supports the planetary gear of the planetary gear mechanism are arranged to engage with the cylinder-side engaging portion of the slide cylinder to engage the input. A carrier-side engaging portion in which rotation of the shaft is transmitted to the carrier as it is, a position where the cylinder-side engaging portion of the slide cylinder in the low-speed mode is separated from the carrier-side engaging portion of the carrier, and In the high-speed mode, a drive unit is provided that moves the slide cylinder between positions where the cylinder-side engagement part of the slide cylinder engages with the carrier-side engagement part of the carrier.

  Furthermore, in the third aspect of the present invention, the carrier-side engaging portion of the carrier is a tip portion of a gear shaft that is fixed to the carrier and rotatably supports the planetary gear of the planetary gear mechanism. It is said.

  In the two-stage transmission according to the first aspect of the present invention, when the high speed mode is selected by the clutch mechanism, the rotational output applied to the input shaft is transmitted to the output shaft through the carrier of the planetary gear mechanism at a high speed, When the low speed mode is switched by the clutch mechanism, the rotational output applied to the input shaft is dropped by the planetary gear mechanism and transmitted to the output shaft.

  In this way, the high-speed rotation output that has not been decelerated and the low-speed rotation output that has been decelerated are selectively switched by a single clutch mechanism and output to the output shaft. The size and weight can be reduced by the amount not required.

  In particular, in the high-speed mode, the rotational output applied to the input shaft is directly transmitted to the output shaft via the carrier of the planetary gear mechanism, so that the structure can be simplified.

  In addition, the annular gear of the planetary gear mechanism is in a fixed state, that is, the annular gear of the gear group constituting the planetary gear mechanism is in a fixed state. The inertial load can be kept small.

  Further, in the two-stage transmission according to claim 2 of the present invention, the slide cylinder is moved in the axial direction by the drive part of the clutch mechanism, and the cylinder side engaging part of the slide cylinder is engaged with the carrier side engaging part of the carrier. When the high-speed mode is selected, the rotational output applied to the input shaft is transmitted to the output shaft as it is.

  On the other hand, when the slide cylinder is moved in the axial direction by the drive unit of the clutch mechanism and the cylinder side engaging part of the slide cylinder is separated from the carrier side engaging part of the carrier and switched to the low speed mode, the speed is reduced by the planetary gear mechanism. The rotational output is transmitted to the output shaft.

  In other words, when switching between the high speed mode in which the rotational output applied to the input shaft is transmitted to the output shaft without decelerating and the low speed mode in which the rotational output applied to the input shaft is decelerated and transmitted to the output shaft, Since only the slide cylinder of the clutch mechanism is moved in the axial direction without using a heavy friction clutch, the size and weight can be further reduced and the structure can be simplified accordingly.

  Furthermore, in the two-stage transmission according to claim 3 of the present invention, since the tip end portion of the gear shaft fixed to the carrier is used as the carrier-side engaging portion of the carrier, compared to the case where the carrier-side engaging portion is provided separately. As a result, the structure can be further simplified.

  In the two-speed transmission according to the present invention, a very excellent effect is achieved that it is possible to realize a simplified structure in addition to a reduction in size and weight.

It is a gear layout explanatory drawing of the planetary gear mechanism of the two-stage transmission by one Example of this invention. FIG. 2 is a cross-sectional explanatory view at the position of the AA line in FIG. 1 in the low-speed mode of the two-stage transmission shown in FIG. 1 and a cross-sectional explanatory view at the position of the BB line in FIG. is there. FIG. 2 is a cross-sectional explanatory view at the position of the AA line in FIG. 1 in the high-speed mode of the two-stage transmission shown in FIG. 1 and a cross-sectional explanatory view at the position of the CC line in FIG. is there.

  Hereinafter, a two-stage transmission according to the present invention will be described with reference to the drawings.

  1 to 3 show an embodiment of a two-speed transmission according to the present invention.

  As shown in FIGS. 1 to 3, the two-stage transmission 1 includes an input shaft 2, an output shaft 3, and a planetary gear mechanism 10, and the input shaft 2 includes a rotation output shaft of a motor (not shown). Are coupled to the output shaft 3, for example, driving wheels (not shown).

  The planetary gear mechanism 10 includes a sun gear 11 formed integrally with the input shaft 2, an annular gear 12 disposed so as to surround the sun gear 11, and a plurality of planets meshing with both the sun gear 11 and the annular gear 12. A gear 13 and a carrier 14 fixed to the output shaft 3 are provided, and the annular gear 12 is fixed to a case (not shown), for example. A base end portion 15 a of a gear shaft 15 that rotatably supports the planetary gear 13 is fixed to the carrier 14 in a penetrating state, and the planetary gear mechanism 10 receives a rotation output from a motor applied to the input shaft 2. It decelerates and outputs.

  The two-stage transmission 1 also includes a low speed mode in which the rotational output applied to the input shaft 2 is dropped by the planetary gear mechanism 10 and output to the output shaft 3, and the rotational output applied to the input shaft 2 is transmitted to the planetary gear mechanism. A clutch mechanism 20 for switching to a high speed mode in which the output is output to the output shaft 3 as it is via the ten carriers 14 is provided.

  The clutch mechanism 20 includes a slide cylinder 21 fitted to the input shaft 2. The slide cylinder 21 and the input shaft 2 are formed with axial splines 21 a and 2 a that are engaged with each other in a state of being fitted to each other, and the slide cylinder 21 is movable in the axial direction with respect to the input shaft 2. And it is connected so that it cannot rotate.

  In this case, the slide cylinder 21 of the clutch mechanism 20 has inward convex portions (cylinder side engaging portions) 21b formed at three locations in the circumferential direction, while the carrier 14 of the planetary gear mechanism 10 has There are three carrier side engaging portions arranged in the circumferential direction in which the rotation of the input shaft 2 is transmitted to the carrier 14 as it is by engaging with the inwardly protruding portions 21b of the slide cylinder 21. In the example, the tip portions 15b of the three gear shafts 15 fixed to the carrier 14 and rotatably supporting the planetary gear 13 function as carrier-side engaging portions.

  In addition, the clutch mechanism 20 includes a position where the inward convex portion 21b of the slide cylinder 21 in the low speed mode is separated from the distal end portion 15b of the gear shaft 15, and the inward convex portion 21b of the slide cylinder 21 in the high speed mode. A linear motion actuator (drive unit) 22 that moves the slide cylinder 21 between a position where it engages with the distal end portion 15b is provided.

  A concave block 22c that is slidably fitted to an annular convex portion 21c formed on the outer peripheral surface of the slide cylinder 21 is disposed at the distal end of the push-pull rod 22a of the linear actuator 22, The slide cylinder 21 is moved in the axial direction of the input shaft 2 by pushing and pulling the push-pull rod 22 a of the actuator 22.

  2 and 3 is a movement restricting plate that restricts the slide cylinder 21 from moving too far to the motor (not shown). Further, reference numeral 16 in FIG. 2 denotes a reinforcing plate that is attached as necessary, and avoids displacement of the tip portions 15 b of the three gear shafts 15 fixed to the carrier 14.

  When the above-described two-stage transmission 1 is mounted on, for example, an electric vehicle, the linear actuator 22 of the clutch mechanism 20 performs a rod pushing operation to move the slide cylinder 21 in the left direction in FIG. When the inward convex portion 21b of the slide cylinder 21 is engaged with the tip portion 15b of the gear shaft 15 to enter the high speed mode, as shown in FIG. 3, the rotational output from the motor (not shown) applied to the input shaft 2 is obtained. Is transmitted to the output shaft 3 through the carrier 14 as it is. That is, the electric vehicle can be driven by high-speed rotation output.

  On the other hand, in this high speed mode, the direct acting actuator 22 of the clutch mechanism 20 performs the rod pulling operation to move the slide cylinder 21 in the right direction in FIG. 3A, and the inward convex portion 21b of the slide cylinder 21 is moved. When separated from the tip 15b of the gear shaft 15 to the low speed mode, the rotational output from the motor decelerated by the planetary gear mechanism 10 is transmitted to the output shaft 3 as shown in FIG. That is, the electric vehicle can be driven by the low-speed rotation output.

  As described above, in the two-stage transmission 1 described above, the high-speed rotation output that is not decelerated and the low-speed rotation output that is decelerated are selectively switched by one clutch mechanism 20 and output to the output shaft 3. Therefore, the size and weight can be reduced by the amount that does not require a plurality of heavy friction clutches.

  In particular, in the high-speed mode, the rotational output applied to the input shaft 2 is transmitted as it is to the output shaft 3 via the carrier 14 of the planetary gear mechanism 10, so that the structure can be simplified.

  Further, the annular gear 12 of the planetary gear mechanism 10 is fixed to a case (not shown), for example, that is, the annular gear 12 of the gear group constituting the planetary gear mechanism 10 is in a fixed state, so that the annular gear 12 rotates. As a result, the inertia load at the time of high-speed rotation output can be kept small.

  Further, in the above-described two-stage transmission 1, the high-speed mode in which the rotational output applied to the input shaft 2 is transmitted to the output shaft 3 without decelerating, and the rotational output applied to the input shaft 2 is decelerated to reduce the output shaft 3 When switching to the low-speed mode transmitted to the vehicle, the slide cylinder 21 of the clutch mechanism 20 is merely moved in the axial direction without using a heavy friction clutch, so that further reduction in size and weight and structure are achieved. Is to be simplified.

  Further, in the above-described two-stage transmission 1, since the tip end portion 15b of the gear shaft 15 fixed to the carrier 14 is used as the carrier-side engaging portion of the carrier 14, the carrier-side engaging portion is used as the gear-side engaging portion of the gear shaft 15. Compared with the case where it is provided separately from the tip 15b, the structure can be further simplified.

  In the above-described embodiment, the case where the two-stage transmission according to the present invention is mounted on an electric vehicle has been described as an example. However, the present invention is not limited to this. For example, the two-stage transmission according to the present invention is not limited to this. You may employ | adopt as a transmission of a machine tool.

  The configuration of the two-speed transmission according to the present invention is not limited to the above-described embodiment. As another configuration, for example, the carrier side engaging portion is arranged integrally or separately on the reinforcing plate 16. May be.

1 Two-speed transmission 2 Input shaft 3 Output shaft
DESCRIPTION OF SYMBOLS 10 Planetary gear mechanism 11 Sun gear 12 Ring gear 13 Planetary gear 14 Carrier 15 Gear shaft 15b The front-end | tip part (carrier side engaging part) of a gear shaft
20 Clutch mechanism 21 Slide cylinder 21b Inward convex part (cylinder side engaging part)
22 Linear Actuator (Driver)

Claims (3)

An input shaft;
An output shaft;
A sun gear rotating coaxially with the input shaft, an annular gear arranged around the sun gear, a planetary gear meshing with both the sun gear and the annular gear, and rotating the planetary gear fixed to the output shaft Comprising a planetary gear mechanism having a carrier for dropping and outputting the rotational output applied to the input shaft by freely supporting,
The annular gear of the planetary gear mechanism is in a fixed state,
A low speed mode in which the rotational output applied to the input shaft is dropped by the planetary gear mechanism and output to the output shaft, and the rotational output applied to the input shaft is output to the output shaft via the carrier of the planetary gear mechanism. A two-stage transmission characterized in that a clutch mechanism is provided for switching between a high-speed mode and an output as it is. The clutch mechanism is
A slide cylinder that is axially movable and non-rotatably fitted to the input shaft;
A cylinder side engaging portion disposed on the slide cylinder fitted to the input shaft;
The rotation of the input shaft is transmitted to the carrier as it is by being arranged on the carrier that rotatably supports the planetary gear of the planetary gear mechanism and engaging with the cylinder side engaging portion of the slide cylinder. A carrier side engaging portion,
The position where the cylinder side engaging portion of the slide cylinder is separated from the carrier side engaging section of the carrier in the low speed mode, and the cylinder side engaging portion of the slide cylinder in the high speed mode is the position of the carrier. The two-stage transmission according to claim 1, further comprising a drive unit that moves the slide cylinder between positions engaged with the carrier side engagement unit.   The two-stage transmission according to claim 2, wherein the carrier side engaging portion of the carrier is a tip portion of a gear shaft fixed to the carrier and rotatably supporting the planetary gear of the planetary gear mechanism.

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