JP6517502B2 - Two-speed transmission - Google Patents

Description

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

  Conventionally, as a two-stage transmission as described above, 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 an input shaft, an annular gear disposed around the sun gear, a planetary gear meshing with both the sun gear and the annular gear, and rotatably supporting the planetary gear. By doing this, a carrier is provided which lowers and outputs the rotational output from the motor given to the input shaft.

  Further, in this two-stage transmission, after setting the ring gear of the planetary gear mechanism in a fixed state, a clutch mechanism for selecting either the carrier rotating with respect to the ring gear or the input shaft and connecting it to the output shaft Have.

  The clutch mechanism includes a cylindrical portion formed on a carrier that rotates with respect to an annular gear and fitted to the input shaft, and rotatably and axially movable inside the cylindrical portion of the carrier on the input shaft. A sleeve, the end of which is axially movably and non-rotatably fitted to the output shaft, the torque transmission ball held by the portion of the sleeve fitted to the input shaft, and the tubular portion of the carrier And the input shaft, which are respectively axially displaced from each other to engage with the torque transmission balls of the sleeve to transmit their rotations to the sleeve, and the torque transmission balls held by the sleeve are the carrier And a drive unit for moving the sleeve between a position of engagement with the engagement portion of the sleeve and a position of engagement with the engagement portion of the input shaft.

  In this two-speed transmission, the sleeve is axially moved by the drive portion of the clutch mechanism, and the torque transmission ball held by the sleeve is engaged with the engagement portion of the input shaft to be applied to the input shaft. The rotational output from the selected motor is directly transmitted to the output shaft, while the sleeve is axially moved by the drive unit of the clutch mechanism to rotate the torque transmission ball held by the sleeve relative to the ring gear By engaging with the engaging portion of the carrier, the planetary gear mechanism is operated to transmit the rotation output from the motor to the output shaft at a low speed.

  As described above, in this two-stage transmission, since one clutch mechanism selectively switches between the high-speed rotational output which is not decelerated and the low-speed rotational output which is decelerated, the weight is output to the output shaft. The reduction in size and weight can be achieved by the fact that multiple sets of bulky friction clutches are not required.

JP, 2011-220484, A

  However, in the above-described conventional two-stage transmission, a heavy-duty friction clutch is used to select either the high-speed rotational output that is not decelerated or the low-speed rotational output that is decelerated and transmit it to the output shaft. Although it is possible to realize size and weight reduction by that amount, as a structure of the clutch mechanism, the position where the torque transmitting ball held by the sleeve engages with the engaging portion of the carrier and the engaging portion of the input shaft Has a problem that the structure of the clutch mechanism can not be said to be simple because the structure for moving the sleeve in the axial direction between the gear and the position where it is engaged is not adopted. It was an issue.

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

According to a first aspect of the present invention, an input shaft, an output shaft, a sun gear coaxially rotating with the input shaft, an annular gear disposed around the sun gear, and both the sun gear and the annular gear The planetary gear comprising: a planetary gear that meshes, and a carrier that is fixed to the output shaft and rotatably supports the planetary gear to reduce and output a rotational output applied to the input shaft; A low speed mode in which the ring gear of the mechanism is fixed and the rotational output given to the input shaft is dropped by the planetary gear mechanism to be output to the output shaft, and the rotational output given to the input shaft is the planetary gear mechanism wherein via a carrier provided with a clutch mechanism for switching between high-speed mode in which it outputs to the output shaft of the clutch mechanism is possible which and nonrotatably fitted axially to said input shaft A slide cylinder, inwardly-directed convex portions formed in a plurality of circumferential positions of the slide cylinder in the slide cylinder fitted to the input shaft, and the planetary gear of the planetary gear mechanism rotatably supported A carrier side engaging portion disposed on the carrier and engaged with the inward convex portion of the slide cylinder to mutually transmit rotation of the input shaft to the carrier as it is, and the slide cylinder in the low speed mode A position at which the inward convex portion is away from the carrier side engaging portion of the carrier, and the inward convex portion of the slide cylinder in the high speed mode engages with the carrier side engaging portion of the carrier A drive unit is provided to move the slide cylinder between positions .

In the second aspect of the present invention, the carrier-side engaging portion of the carrier is a tip end portion of a gear shaft fixed to the carrier and rotatably supporting the planetary gear of the planetary gear mechanism. And

  In the two-stage transmission according to claim 1 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 while maintaining high speed. When the clutch mechanism is switched to the low speed mode, the rotational output applied to the input shaft is dropped by the planetary gear mechanism and transmitted to the output shaft.

  As described above, one clutch mechanism selectively switches between the high-speed rotational output not being decelerated and the low-speed rotational output that is decelerated and outputs the selected output to the output shaft. The reduction in size and weight can be achieved as much as unnecessary.

  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, since the ring gear of the planetary gear mechanism is in a fixed state, that is, since the ring gear of the gear group constituting the planet gear mechanism is in a fixed state, at the time of high speed rotation output Inertial load can be reduced.

Further, in a two-stage transmission according to claim 1 of the present invention, the drive unit of the clutch mechanism to move the slide cylindrical axially engaging the inward convex portion of the slide cylinder to the carrier-side engagement portion of the carrier In the high speed mode, the rotational output applied to the input shaft is directly transmitted to the output shaft.

On the other hand, when the slide cylinder is axially moved by the drive portion of the clutch mechanism and the inward convex portion of the slide cylinder is separated from the carrier side engaging portion of the carrier to switch to the low speed mode, the rotation reduced by the planetary gear mechanism The output is transmitted to the output shaft.

  That is, 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 transmitted to the output shaft by decelerating Since only the slide cylinder of the clutch mechanism is moved in the axial direction without using a heavy friction clutch, further reduction in size and weight and simplification of the structure can be achieved.

Furthermore, in the two-speed transmission according to claim 2 of the present invention, since the tip 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 separately provided. Thus, the structure can be further simplified.

  The two-speed transmission according to the present invention brings about a very excellent effect that it is possible to realize simplification of the structure in addition to the reduction in size and weight.

It is gear layout explanatory drawing of the planetary gear mechanism of the two-step transmission by one Example of this invention. 1A and 1B in a low speed mode of the two-speed transmission shown in FIG. 1A and FIG. 2A in a sectional view of FIG. 2A at a line B-B. is there. 1A and 1B in a high speed mode of the two-speed transmission shown in FIG. 1A and FIG. 3A in a sectional view of FIG. is there.

  Hereinafter, a two-speed transmission according to the present invention will be described based on 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, this two-speed transmission 1 includes an input shaft 2, an output shaft 3, and a planetary gear mechanism 10, and a rotational output shaft of a motor (not shown) is not shown. Are connected, and for example, a driving wheel (not shown) is connected to the output shaft 3.

The planetary gear mechanism 10 includes a sun gear 11 rotating coaxially with the input shaft 2 , an annular gear 12 disposed around the sun gear 11, and a plurality of planetary gears meshing with both the sun gear 11 and the annular gear 12. 13 and a carrier 14 fixed to the output shaft 3, and the annular gear 12 is fixed to, for example, a case (not shown). The base end portion 15 a of the gear shaft 15 rotatably supporting the planetary gear 13 is fixed to the carrier 14 in a penetrating state, and the planetary gear mechanism 10 outputs the rotational output from the motor provided to the input shaft 2. It decelerates and outputs.

  The two-speed transmission 1 also has a low speed mode in which the rotational output provided to the input shaft 2 is dropped by the planetary gear mechanism 10 and output to the output shaft 3, and the rotational output provided to the input shaft 2 A clutch mechanism 20 is provided which switches between a high speed mode in which the output shaft 3 is output as it is through the ten carriers 14.

  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 splines 21 a and 2 a in the axial direction which are engaged with each other in a mutually fitted state, and the slide cylinder 21 is axially movable with respect to the input shaft 2 And it is connected non-rotatably.

In this case, the inward convex portions 21b are formed at three places in the circumferential direction on the slide cylinder 21 of the clutch mechanism 20, while the inward convex of the slide cylinder 21 is formed on the carrier 14 of the planetary gear mechanism 10. The carrier side engaging portions, in which the rotation of the input shaft 2 is transmitted to the carrier 14 as it is by engaging with the portion 21b, are arranged at three places in the circumferential direction, and in this embodiment, fixed to the carrier 14 The front ends 15b of the three gear shafts 15 rotatably supporting the planetary gears 13 function as carrier side engaging parts.

  In the clutch mechanism 20, the inward convex portion 21b of the slide cylinder 21 in the low speed mode is away from the tip end 15b of the gear shaft 15, and the inward convex portion 21b of the slide cylinder 21 in the high speed mode is the gear shaft 15. A linear actuator (drive unit) 22 is provided to move the slide cylinder 21 between a position where it engages with the tip end 15b.

  A concave block 22c which is slidably fitted with an annular convex portion 21c formed on the outer peripheral surface of the slide cylinder 21 is disposed at the tip 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, reference numeral 24 denotes a movement restricting plate, which restricts the slide cylinder 21 from moving to the motor side (not shown). Further, reference numeral 16 in FIG. 2 denotes a reinforcing plate which is mounted as needed, and prevents positional deviation of the respective tip portions 15 b of the three gear shafts 15 fixed to the carrier 14.

  When the above-described two-speed 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 of FIG. When the inward convex portion 21b of the slide cylinder 21 is engaged with the tip end portion 15b of the gear shaft 15 to be in the high speed mode, the rotational output from the motor (not shown) applied to the input shaft 2 as shown in FIG. Is transmitted to the output shaft 3 as it is via the carrier 14. That is, traveling of the electric vehicle by high-speed rotational output becomes possible.

  On the other hand, in this high speed mode, the linear actuator 22 of the clutch mechanism 20 is caused to pull in the rod to move the slide cylinder 21 to the right in FIG. 3A, and the inward convex portion 21b of the slide cylinder 21 is moved. When it is separated from the tip end portion 15b of the gear shaft 15 to be in 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, traveling of the electric vehicle by low-speed rotational output becomes possible.

  As described above, in the above-described two-stage transmission 1, one clutch mechanism 20 selectively switches between the high-speed rotational output which is not decelerated and the low-speed rotational output which is decelerated and outputs it to the output shaft 3. Therefore, the size and weight can be reduced by the amount of not requiring a plurality of heavy friction clutches.

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

  Further, the ring gear 12 of the planetary gear mechanism 10 is fixed to, for example, a case (not shown), that is, since the ring gear 12 of the gear group constituting the planet gear mechanism 10 is fixed, the ring gear 12 rotates. The inertia load at the time of high-speed rotation output can be suppressed to a small amount by the amount that is not.

  Furthermore, in the two-stage transmission 1 described above, the high speed mode for transmitting the rotation output provided to the input shaft 2 to the output shaft 3 without decelerating and the rotation output provided for the input shaft 2 When switching to the low-speed mode for transferring to the low-speed mode, the slide cylinder 21 of the clutch mechanism 20 is only moved in the axial direction without using a heavy-duty friction clutch. Will be simplified.

  Furthermore, in the above-described two-speed transmission 1, the tip end portion 15 b of the gear shaft 15 fixed to the carrier 14 is used as the carrier side engaging portion of the carrier 14. Further simplification of the structure can be achieved as compared with the case where they are provided separately from the tip 15b.

  In the above embodiment, the case where the two-speed transmission according to the present invention is mounted on an electric vehicle is described as an example, but the present invention is not limited to this. For example, the two-speed transmission according to the present invention 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, and as another configuration, for example, the carrier side engaging portion is disposed integrally or separately with 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 Planet gear 14 Carrier 15 Gear shaft 15b Tip end portion of gear shaft (carrier side engaging portion)
20 clutch mechanism 21 slide cylinders 21b inward protrusion
22 Linear actuator (drive unit)

Claims (2)

With the input axis
An output axis,
A sun gear coaxially rotating with the input shaft, an annular gear disposed around the sun gear, a planetary gear meshing with both the sun gear and the annular gear, fixed to the output shaft to rotate the planetary gear It has a planetary gear mechanism equipped with a carrier that lowers and outputs a rotational output given to the input shaft by freely supporting it,
The ring gear of the planetary gear mechanism is fixed,
The low speed mode in which the rotational output given to the input shaft is dropped by the planetary gear mechanism and output to the output shaft, and the rotational output given to the input shaft through the carrier of the planetary gear mechanism the clutch mechanism as it switches between high-speed mode for outputting the provided,
The clutch mechanism is
A slide cylinder axially movably and non-rotatably fitted to the input shaft;
Inward convex portions formed at a plurality of circumferential positions of the slide cylinder in the slide cylinder fitted to the input shaft;
It arrange | positions to the said carrier which supports the said planetary gear of the said planetary gear mechanism rotatably, and rotation of the said input shaft is transmitted to this carrier as it is by mutually engaging with the said inward convex part of the said slide cylinder A carrier side engaging portion,
The position in which the inward convex portion of the slide cylinder in the low speed mode is away from the carrier side engaging portion of the carrier, and the inward convex portion of the slide cylinder in the high speed mode is the carrier side of the carrier A two-step transmission comprising a drive unit for moving the slide cylinder between positions engaged with the engagement unit . The two-step transmission according to claim 1 , wherein the carrier-side engaging portion of the carrier is a tip end portion of a gear shaft fixed to the carrier and rotatably supporting the planetary gear of the planetary gear mechanism.

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