Motive power converting device

Abstract

A radius (r1) of a ring gear (RG) is twice a radius (r2) of a first planet gear (PG1), and the first planet gear (PG1) and a second planet gear (PG2) are configured to revolve in the same direction at the same speed around a carrier axis (X1), which is the rotational axis of a carrier (CR), wherein: when viewed in the axial direction, a first planetary axis (X2), which is the rotational axis of the first planet gear (PG1), and a second planetary axis (X3), which is the rotational axis of the second planet gear (PG2), are on opposite sides of the carrier axis (X1), and are disposed in positions that are the same distance from the carrier axis (X1); and in an axial view, a first crank member (2) is connected to the first planet gear (PG1) and a second crank member (4) is connected to the second planet gear (PG2) such that a first input shaft axis (X4) separated from the first planetary axis (X2) in a first planet radial direction (Rp1) and a second input shaft axis (X5) separated from the second planetary axis (X3) in a second planetary radial direction (Rp2) are positioned on opposite sides of the carrier axis (X1).

Description

Power conversion device

[0001] The present invention relates to a power conversion device that converts reciprocating motion into rotational motion.

[0002] Patent Document 1 discloses a power conversion device mounted on a bicycle or the like. In the power conversion device of Patent Document 1, the reciprocating motion of an input member (85) caused by human power is converted into the rotational motion of an output member (1) via a planetary gear mechanism or the like. Note that the reference numerals in parentheses in the description of the background art are those of Patent Document 1.

[0003] Japanese Patent Application Publication No. 9-323691

[0004] In the power conversion device of Patent Document 1, the input member (85) moves along a curved path at a position offset from the rotation axis of the output member (1) (see Figure 3 of Patent Document 1). Therefore, the power conversion device is configured such that it is difficult to transmit driving force to the input member (85).

[0005] Therefore, it is desirable to realize a power conversion device that can easily transmit driving force to an input member.

[0006] In view of the above, the characteristic configuration of the power conversion device is: a planetary gear mechanism including a ring gear which is a fixed internal gear, first planetary gears which mesh with the ring gear, second planetary gears which are arranged on axes separate from the first planetary gears, and a carrier which rotatably supports the first planetary gears and the second planetary gears; a first crank member which is arranged to extend in a first planetary radial direction which is perpendicular to a first planetary axis which is the rotational axis of the first planetary gears and is connected to rotate integrally with the first planetary gears; a first input member which is supported by the first crank member and is arranged on a first input axis which is spaced from the first planetary axis in the first planetary radial direction; and a second crank member which is arranged to extend in a second planetary radial direction which is perpendicular to a second planetary axis which is the rotational axis of the second planetary gears and is connected to rotate integrally with the second planetary gears; the second input member is supported by the second crank member and is arranged on a second input shaft spaced apart from the second planetary axis in the second planet radial direction; and an output member is connected to a specific rotating member that rotates in conjunction with the carrier, excluding the first planetary gear and the second planetary gear, wherein the radius of the ring gear is twice the radius of the first planetary gear, and the axial direction is a direction along the carrier axis, which is the rotation axis of the carrier, and the first planetary gear and the second planetary gear are configured to revolve around the carrier axis at the same speed and in the same direction, and when viewed in the axial direction along the axial direction, the first planetary axis and the second planetary axis are arranged on opposite sides of the carrier axis and at positions that are the same distance from the carrier axis, The first crank member is connected to the first planetary gear, and the second crank member is connected to the second planetary gear, so that, when viewed in the axial direction, the first input shaft center and the second input shaft center are located on opposite sides of the carrier shaft center.

[0007] According to this characteristic configuration, the movement loci of the first input shaft center and the second input shaft center associated with the reciprocating motion of the first input member and the second input member can be linear or elliptical with respect to the carrier axis center. Furthermore, the phase difference between the first input shaft center and the second input shaft center can be set to 180° or a value close to that. Therefore, a power conversion device that can easily transmit driving force to the first input member disposed on the first input shaft center and the second input member disposed on the second input shaft center can be realized.

[0008] 1 is a cross-sectional view of a power conversion device according to a first embodiment; 2 is a diagram showing the reciprocating motion of a first input member and a second input member according to the first embodiment; 3 is a diagram showing the reciprocating motion of a first input member and a second input member according to the first embodiment; 4 is a diagram showing the reciprocating motion of a first input member and a second input member according to the first embodiment; 5 is a diagram showing the reciprocating motion of a first input member and a second input member according to the first embodiment; 6 is a diagram showing the reciprocating motion of a first input member and a second input member according to the first embodiment;

[0009] 1. First Embodiment A power conversion device 100 according to a first embodiment will be described below with reference to FIGS. 1 to 7. FIG.

[0010] 1, the power conversion device 100 includes a planetary gear mechanism 1, a first crank member 2, a first input member 3, a second crank member 4, a second input member 5, and an output member 6. The power conversion device 100 converts the reciprocating motion of the first input member 3 and the second input member 5 into the rotational motion of the output member 6 by the planetary gear mechanism 1.

[0011] The planetary gear mechanism 1 includes a ring gear RG, a first planetary gear PG1, a second planetary gear PG2, and a carrier CR. The ring gear RG is an internal gear that is fixed so as not to rotate. The first planetary gear PG1 meshes with the ring gear RG. The second planetary gear PG2 is disposed on a separate axis from the first planetary gear PG1. The carrier CR rotatably supports the first planetary gear PG1 and the second planetary gear PG2.

[0012] In the following description, the direction along the carrier axis X1, which is the rotation axis of the carrier CR, is referred to as the "axial direction L." One side of the axial direction L is referred to as the "first axial side L1," and the other side of the axial direction L is referred to as the "second axial side L2." Furthermore, the direction perpendicular to the carrier axis X1 is referred to as the "radial direction R." Furthermore, the direction perpendicular to the first planet axis X2, which is the rotation axis of the first planetary gear PG1, is referred to as the "first planetary radial direction Rp1." Furthermore, the direction perpendicular to the second planet axis X3, which is the rotation axis of the second planetary gear PG2, is referred to as the "second planetary radial direction Rp2."

[0013] The first planetary gear PG1 and the second planetary gear PG2 are configured to rotate (revolve) around the carrier axis X1 at the same speed and in the same direction.

[0014] The first planetary gear PG1 is configured to rotate (spin) about the first planetary axis X2. In this embodiment, the first planetary gear PG1 is coupled to a first planetary shaft PS1, which is a shaft member whose rotation axis is the first planetary axis X2, so as to rotate integrally with the first planetary gear PG1. In this embodiment, the first planetary shaft PS1 is disposed so as to penetrate the first planetary gear PG1 in the axial direction L. The first planetary shaft PS1 is rotatably supported relative to the carrier CR via a pair of first planetary bearings B1 disposed separately on both sides of the first planetary gear PG1 in the axial direction L.

[0015] The second planetary gear PG2 is configured to rotate (spin) about the second planetary axis X3. In this embodiment, the second planetary gear PG2 is coupled to a second planetary shaft PS2, which is a shaft member whose rotational axis is the second planetary axis X3, so as to rotate integrally with the second planetary shaft PS2. In this embodiment, the second planetary shaft PS2 is disposed so as to penetrate the second planetary gear PG2 in the axial direction L. The second planetary shaft PS2 is rotatably supported relative to the carrier CR via a pair of second planetary bearings B2 disposed separately on both sides of the second planetary gear PG2 in the axial direction L.

[0016] In this embodiment, the planetary gear mechanism 1 further includes a second ring gear RG2 in addition to a first ring gear RG1 serving as the ring gear RG.

[0017] The second ring gear RG2 is an internal gear that is fixed so as not to rotate. The second ring gear RG2 is meshed with the second planetary gear PG2. In this embodiment, the second ring gear RG2 is disposed on the second axial side L2 relative to the first ring gear RG1.

[0018] In this embodiment, the first ring gear RG1 and the second ring gear RG2 are fixed to a ring gear support portion RS that is disposed between them in the axial direction L. The ring gear support portion RS rotatably supports the carrier CR from the outside in the radial direction R via a ring gear bearing B3. In this embodiment, the ring gear support portion RS is formed to extend inward in the radial direction R from the first ring gear RG1 and the second ring gear RG2. The first planetary gear PG1 and the first planetary shaft PS1 are disposed on a first axial side L1 of the ring gear support portion RS, and the second planetary gear PG2 and the second planetary shaft PS2 are disposed on a second axial side L2 of the ring gear support portion RS.

[0019] The radius r1 of the ring gear RG (first ring gear RG1) is twice the radius r2 of the first planetary gear PG1 (r1 = r2 × 2). Therefore, the first planetary gear PG1 rotates once around the first planetary axis X2 while making one revolution around the carrier axis X1. In other words, the revolution period and rotation period of the first planetary gear PG1 are equal. Note that in this application, "gear radius" refers to the radius of the pitch circle of that gear.

[0020] In this embodiment, the radius r3 of the second ring gear RG2 is twice the radius r4 of the second planetary gear PG2 (r3 = r4 × 2). Therefore, in this embodiment, the second planetary gear PG2 rotates once about the second planetary axis X3 while making one revolution about the carrier axis X1. In other words, in this embodiment, the revolution period and rotation period of the second planetary gear PG2 are equal.

[0021] In this embodiment, the first ring gear RG1 and the second ring gear RG2 have the same diameter (r1 = r3), and the first planetary gear PG1 and the second planetary gear PG2 have the same diameter (r2 = r4).

[0022] As shown in Fig. 1, the first crank member 2 is disposed to extend in the first planetary radial direction Rp1. The first crank member 2 extends between the first planetary axis X2 and a first input axis X4 spaced from the first planetary axis X2 in the first planetary radial direction Rp1. The first crank member 2 is coupled to the first planetary gear PG1 so as to rotate integrally with the first planetary gear PG1. In this embodiment, the first crank member 2 is coupled to a portion of the first planetary shaft PS1 that is closer to the first axial side L1 than the first planetary gear PG1 so as to be non-rotatable relative to the first planetary shaft PS1.

[0023] The first input member 3 is a member to which a predetermined driving force is input from outside the power conversion device 100. The first input member 3 is disposed on the first input axis X4. The first input member 3 is supported by the first crank member 2. In this embodiment, the first input member 3 is a shaft member disposed so as to protrude from the first crank member 2 to the first axial side L1. The first input member 3 is coupled to the first crank member 2 so as to rotate integrally with the first crank member 2.

[0024] The second crank member 4 is disposed to extend in the second planetary radial direction Rp2. The second crank member 4 extends between the second planetary axis X3 and a second input axis X5 spaced from the second planetary axis X3 in the second planetary radial direction Rp2. The second crank member 4 is connected to the second planetary gear PG2 so as to rotate integrally with the second planetary gear PG2. In this embodiment, the second crank member 4 is connected to a portion of the second planetary shaft PS2 that is closer to the second axial side L2 than the second planetary gear PG2 so as to be non-rotatable relative to the second planetary shaft PS2.

[0025] The second input member 5 is a member to which a predetermined driving force is input from outside the power conversion device 100. The second input member 5 is disposed on the second input axis X5. The second input member 5 is supported by the second crank member 4. In this embodiment, the second input member 5 is a shaft member disposed so as to protrude from the second crank member 4 toward the second axial side L2. The second input member 5 is coupled to the second crank member 4 so as to rotate integrally with the second crank member 4.

[0026] In this embodiment, the distance d1 in the first planetary radial direction Rp1 between the first planetary axis X2 and the first input axis X4 is the same as the distance d2 in the second planetary radial direction Rp2 between the second planetary axis X3 and the second input axis X5 (d1 = d2). Furthermore, the radius r2 of the first planetary gear PG1 is the same as the distance d1 in the first planetary radial direction Rp1 between the first planetary axis X2 and the first input axis X4 (r2 = d1). Furthermore, the radius r4 of the second planetary gear PG2 is the same as the distance d2 in the second planetary radial direction Rp2 between the second planetary axis X3 and the second input axis X5 (r4 = d2).

[0027] In this embodiment, a first pedal P1 (described later) is connected to the first input member 3 so as to be rotatable relative to the first pedal P1. A second pedal P2 (described later) is connected to the second input member 5 so as to be rotatable relative to the second pedal P2.

[0028] The output member 6 is connected to a specific rotating member RT. The specific rotating member RT is a rotating member other than the first planetary gear PG1 and the second planetary gear PG2, and is a rotating member that rotates in conjunction with the carrier CR. In this embodiment, the specific rotating member RT is the carrier CR. Here, "rotating in conjunction with" includes rotating at the same speed and rotating at a predetermined gear ratio, regardless of the rotation direction.

[0029] 2 to 6, the reciprocating motion of the first input member 3 and the second input member 5 according to this embodiment will be described. In addition, in Figures 2 to 6, a locus T1 indicated by a dashed line is the movement locus of the first input shaft center X4 and the second input shaft center X5 associated with the reciprocating motion of the first input member 3 and the second input member 5. Furthermore, a locus T2 indicated by a dashed line is the movement locus of the first planetary shaft center X2 and the second planetary shaft center X3 associated with the reciprocating motion of the first input member 3 and the second input member 5.

[0030] As described above, the first planetary gear PG1 and the second planetary gear PG2 revolve around the carrier axis X1. Therefore, the locus T2, which is the movement locus of the first planetary axis X2, which is the rotational axis of the first planetary gear PG1, and the second planetary axis X3, which is the rotational axis of the second planetary gear PG2, is circular with the carrier axis X1 as the center when viewed in the axial direction L.

[0031] As described above, in this embodiment, the first ring gear RG1 and the second ring gear RG2 have the same diameter, and the first planetary gear PG1 and the second planetary gear PG2 have the same diameter. Therefore, in this embodiment, the movement locus of the first planetary axis X2 and the movement locus of the second planetary axis X3 caused by the reciprocating motion of the first input member 3 and the second input member 5 coincide with each other when viewed in the axial direction L.

[0032] 2 to 6 , in an axial view along the axial direction L, the first planetary axis X2 and the second planetary axis X3 are disposed on opposite sides of the carrier axis X1 and at positions that are the same distance from the carrier axis X1. In this embodiment, in an axial view along the axial direction L, the first planetary axis X2, the carrier axis X1, and the second planetary axis X3 are disposed so as to be aligned on a straight line. That is, in this embodiment, the first planetary axis X2 and the second planetary axis X3 are disposed with a phase difference of 180°.

[0033] 2 to 6 , the first crank member 2 is connected to the first planetary gear PG1, and the second crank member 4 is connected to the second planetary gear PG2, so that the first input shaft center X4 and the second input shaft center X5 are located on opposite sides of the carrier shaft center X1 when viewed in the axial direction L. In this embodiment, the direction along a straight line passing through the first planetary shaft center X2 and the first input shaft center X4, i.e., the extension direction of the first crank member 2, and the direction along a straight line passing through the second planetary shaft center X3 and the second input shaft center X5, i.e., the extension direction of the second crank member 4, are arranged so as to be parallel to each other.

[0034] As described above, in this embodiment, the radius r2 of the first planetary gear PG1 is the same as the distance d1 in the first planetary radius direction Rp1 between the first planetary axis center X2 and the first input axis center X4, and the radius r4 of the second planetary gear PG2 is the same as the distance d2 in the second planetary radius direction Rp2 between the second planetary axis center X3 and the second input axis center X5. Therefore, in this embodiment, the locus T1, which is the movement locus of the first input axis center X4 and the second input axis center X5, is a straight line that passes through the carrier axis center X1 when viewed in the axial direction along the axial direction L.

[0035] As described above, in this embodiment, the distance d1 in the first planetary radial direction Rp1 between the first planetary axis X2 and the first input axis X4 is the same as the distance d2 in the second planetary radial direction Rp2 between the second planetary axis X3 and the second input axis X5. The first input axis X4, the carrier axis X1, and the second input axis X5 are arranged to be aligned on a straight line when viewed in the axial direction L. Therefore, in this embodiment, the movement locus of the first input axis X4 and the movement locus of the second input axis X5 accompanying the reciprocating motion of the first input member 3 and the second input member 5 coincide with each other when viewed in the axial direction L.

[0036] 2, in an axial view along the axial direction L, the first input shaft center X4 is located on the opposite side of the carrier shaft center X1 with respect to the first planetary shaft center X2, and the second input shaft center X5 is located on the opposite side of the carrier shaft center X1 with respect to the second planetary shaft center X3. In addition, in an axial view along the axial direction L, the first input shaft center X4, the first planetary shaft center X2, the carrier shaft center X1, the second planetary shaft center X3, and the second input shaft center X5 are aligned on a straight line. In this case, based on the circular locus T2, the phase of the first planetary shaft center X2 is set to 0°, and the phase of the second planetary shaft center X3 is set to 180°.

[0037] In the example shown in Fig. 3, the first planetary shaft center X2 and the second planetary shaft center X3 are rotated 45° clockwise around the carrier shaft center X1 from the state shown in Fig. 2. In other words, the phase of the first planetary shaft center X2 is 45°, and the phase of the second planetary shaft center X3 is 225°. At this time, the first input shaft center X4 and the second input shaft center X5 are closer to the carrier shaft center X1 than in the state shown in Fig. 2.

[0038] In the example shown in Fig. 4, the first planetary shaft center X2 and the second planetary shaft center X3 are rotated 45° clockwise around the carrier shaft center X1 from the state shown in Fig. 3. In other words, the phase of the first planetary shaft center X2 is 90°, and the phase of the second planetary shaft center X3 is 270°. At this time, the first input shaft center X4 and the second input shaft center X5 are positioned on the carrier shaft center X1.

[0039] In the example shown in Fig. 5, the first planetary shaft center X2 and the second planetary shaft center X3 are rotated 45° clockwise around the carrier shaft center X1 from the state shown in Fig. 4. In other words, the phase of the first planetary shaft center X2 is 135°, and the phase of the second planetary shaft center X3 is 315°. At this time, the first input shaft center X4 and the second input shaft center X5 are farther away from the carrier shaft center X1 than in the state shown in Fig. 4.

[0040] In the example shown in Fig. 6, the first planetary shaft center X2 and the second planetary shaft center X3 are rotated 45° clockwise around the carrier shaft center X1 from the state shown in Fig. 5. In other words, the phase of the first planetary shaft center X2 is 180°, and the phase of the second planetary shaft center X3 is 0°. At this time, as viewed in the axial direction L, the first input shaft center X4 is located on the opposite side of the carrier shaft center X1 with respect to the first planetary shaft center X2, and the second input shaft center X5 is located on the opposite side of the carrier shaft center X1 with respect to the second planetary shaft center X3. As viewed in the axial direction L, the first input shaft center X4, the first planetary shaft center X2, the carrier shaft center X1, the second planetary shaft center X3, and the second input shaft center X5 are aligned on a straight line.

[0041] Note that, although a description of the process until the phase of the first planetary shaft center X2 becomes 0° will be omitted, as described above, the first input member 3 and the second input member 5 perform reciprocating motion so that the first input shaft center X4 and the second input shaft center X5 describe a linear locus T1.

[0042] As described above, the first crank member 2 is connected to the first planetary gear PG1, and the second crank member 4 is connected to the second planetary gear PG2, so that the first input shaft center X4 and the second input shaft center X5 are located on opposite sides of the carrier axis center X1 when viewed in the axial direction L. In this embodiment, the locus T1 is described so that the first input shaft center X4 and the second input shaft center X5 pass on the carrier axis center X1. Therefore, in this application, "the first input shaft center X4 and the second input shaft center X5 are located on opposite sides of the carrier axis center X1 when viewed in the axial direction L" includes being disposed so that at least one of the first input shaft center X4 and the second input shaft center X5 describes the locus T1 that passes on the carrier axis center X1.

[0043] As shown in Figure 7, in this embodiment, the power conversion device 100 is mounted on a bicycle B. Therefore, in this embodiment, the power conversion device 100 converts the reciprocating motion of the first input member 3 and the second input member 5, which is operated by the rider of the bicycle B, into rotational motion of the output member 6 and outputs the rotational motion. In the example shown in Figure 7, the power conversion device 100 is positioned so that the trajectory T1 is inclined relative to the horizontal direction and points upward as it approaches the rear of the bicycle B (the right side in Figure 7).

[0044] The bicycle B includes a seat S, a handle H, a frame F, a driving wheel W1, a driven wheel W2, and a transmission mechanism T in addition to the first pedal P1 and the second pedal P2.

[0045] The first pedal P1 and the second pedal P2 are members that the driver steps on with his / her feet. The seat S is a member on which the driver sits. The handle H is a member that the driver grips. The frame F is a member that supports the seat S, the handle H, the driving wheels W1, the driven wheels W2, and the power conversion device 100. The ring gear RG of the planetary gear mechanism 1 in the power conversion device 100 is fixed to the frame F via a ring gear fixing member RF.

[0046] The drive wheel W1 is configured to rotate in conjunction with the driver's operation. The driven wheel W2 is rotatably supported on the frame F. In this embodiment, the drive wheel W1 is a rear wheel, and the driven wheel W2 is a front wheel.

[0047] The transmission mechanism T is configured to transmit the rotation of the output member 6 of the power conversion device 100 to the drive wheel W1. In this embodiment, the transmission mechanism T includes a first sprocket SP1, a second sprocket SP2, a third sprocket SP3, a fourth sprocket SP4, a first chain CH1, and a second chain CH2.

[0048] The first sprocket SP1 is disposed on the carrier axis X1. In this embodiment, the first sprocket SP1 is coupled to the carrier CR, which serves as the specific rotating member RT, so as to rotate integrally with the carrier CR (see FIG. 1). That is, in this embodiment, the first sprocket SP1 functions as the output member 6.

[0049] The first chain CH1 is wound around the first sprocket SP1 and the second sprocket SP2. Therefore, the second sprocket SP2 rotates in accordance with the rotation of the first sprocket SP1. In the example shown in Figure 7, the second sprocket SP2 has a smaller diameter than the first sprocket SP1.

[0050] The third sprocket SP3 is arranged coaxially with the second sprocket SP2 and is connected to the second sprocket SP2 so as to rotate integrally with the second sprocket SP2. In the example shown in Figure 7, the third sprocket SP3 has a larger diameter than the second sprocket SP2.

[0051] The second chain CH2 is wound around a third sprocket SP3 and a fourth sprocket SP4. The fourth sprocket SP4 is disposed coaxially with the drive wheel W1. In the example shown in Figure 7, the fourth sprocket SP4 has a smaller diameter than the third sprocket SP3.

[0052] 2. Second Embodiment A power conversion device 100 according to a second embodiment will be described below with reference to FIGS. 8 to 14. In this embodiment, the configurations of the first crank member 2 and the second crank member 4 are different from those of the first embodiment. The following description will focus on the differences from the first embodiment. Note that points not specifically described are the same as those in the first embodiment.

[0053] As shown in FIG. 8 , in this embodiment, the radius r2 of the first planetary gear PG1 is different from the distance d1 in the first planetary radial direction Rp1 between the first planetary axis X2 and the first input axis X4 (r2≠d1). The radius r4 of the second planetary gear PG2 is different from the distance d2 in the second planetary radial direction Rp2 between the second planetary axis X3 and the second input axis X5 (r4≠d2). In the example shown in FIG. 8 , the distance d1 in the first planetary radial direction Rp1 between the first planetary axis X2 and the first input axis X4 is greater than the radius r2 of the first planetary gear PG1 (r2<d1). The distance d2 in the second planetary radial direction Rp2 between the second planetary axis X3 and the second input axis X5 is greater than the radius r4 of the second planetary gear PG2 (r4<d2). In this embodiment, as in the first embodiment, the distance d1 in the first planetary radial direction Rp1 between the first planetary axis center X2 and the first input axis center X4 is the same as the distance d2 in the second planetary radial direction Rp2 between the second planetary axis center X3 and the second input axis center X5 (d1 = d2).

[0054] 9 to 13, the reciprocating motion of the first input member 3 and the second input member 5 according to this embodiment will be described. In addition, in Fig. 9 to 13, a locus T1 indicated by a dashed line is the movement locus of the first input shaft center X4 and the second input shaft center X5 caused by the reciprocating motion of the first input member 3 and the second input member 5. Furthermore, a locus T2 indicated by a dashed line is the movement locus of the first planetary shaft center X2 and the second planetary shaft center X3 caused by the reciprocating motion of the first input member 3 and the second input member 5.

[0055] As described above, in this embodiment, the radius r2 of the first planetary gear PG1 is different from the distance d1 in the first planetary radius direction Rp1 between the first planetary axis center X2 and the first input axis center X4, and the radius r4 of the second planetary gear PG2 is different from the distance d2 in the second planetary radius direction Rp2 between the second planetary axis center X3 and the second input axis center X5. Therefore, in this embodiment, the locus T1, which is the movement locus of the first input axis center X4 and the second input axis center X5, is elliptical about the carrier axis center X1 when viewed in the axial direction L.

[0056] As described above, in this embodiment, the distance d1 in the first planetary radial direction Rp1 between the first planetary axis X2 and the first input axis X4 is the same as the distance d2 in the second planetary radial direction Rp2 between the second planetary axis X3 and the second input axis X5. The first input axis X4, the carrier axis X1, and the second input axis X5 are arranged to be aligned on a straight line when viewed in the axial direction L. Therefore, in this embodiment, the movement locus of the first input axis X4 and the movement locus of the second input axis X5 accompanying the reciprocating motion of the first input member 3 and the second input member 5 coincide with each other when viewed in the axial direction L.

[0057] 9 , in an axial view along the axial direction L, the first input shaft center X4 is located on the opposite side of the carrier shaft center X1 with respect to the first planetary shaft center X2, and the second input shaft center X5 is located on the opposite side of the carrier shaft center X1 with respect to the second planetary shaft center X3. In addition, in an axial view along the axial direction L, the first input shaft center X4, the first planetary shaft center X2, the carrier shaft center X1, the second planetary shaft center X3, and the second input shaft center X5 are aligned on a straight line. In this case, based on the circular locus T2, the phase of the first planetary shaft center X2 is set to 0°, and the phase of the second planetary shaft center X3 is set to 180°.

[0058] In the example shown in Fig. 10, the first planetary shaft center X2 and the second planetary shaft center X3 have rotated 45° clockwise around the carrier shaft center X1 from the state shown in Fig. 9. In other words, the phase of the first planetary shaft center X2 is 45°, and the phase of the second planetary shaft center X3 is 225°. At this time, the first input shaft center X4 and the second input shaft center X5 have rotated counterclockwise around the carrier shaft center X1 from the state shown in Fig. 9.

[0059] In the example shown in Fig. 11, the first planetary shaft center X2 and the second planetary shaft center X3 are rotated 45° clockwise around the carrier shaft center X1 from the state shown in Fig. 10. In other words, the phase of the first planetary shaft center X2 is 90°, and the phase of the second planetary shaft center X3 is 270°. At this time, when viewed in the axial direction L, the first input shaft center X4 and the second input shaft center X5 are located on a straight line passing through the first planetary shaft center X2, the carrier shaft center X1, and the second planetary shaft center X3. In other words, when viewed in the axial direction along the axial direction L, the first input axis X2, the second input axis X5, the carrier axis X1, the first input axis X4, and the second planetary axis X3 are aligned in a straight line so that the first input axis X4 is located between the carrier axis X1 and the second planetary axis X3, and the second input axis X5 is located between the carrier axis X1 and the first planetary axis X2.

[0060] In the example shown in Fig. 12, the first planetary shaft center X2 and the second planetary shaft center X3 have rotated 45° clockwise around the carrier shaft center X1 from the state shown in Fig. 11. In other words, the phase of the first planetary shaft center X2 is 135°, and the phase of the second planetary shaft center X3 is 315°. At this time, the first input shaft center X4 and the second input shaft center X5 have rotated counterclockwise around the carrier shaft center X1 from the state shown in Fig. 11.

[0061] In the example shown in Fig. 13, the first planetary shaft center X2 and the second planetary shaft center X3 are rotated 45° clockwise around the carrier shaft center X1 from the state shown in Fig. 12. In other words, the phase of the first planetary shaft center X2 is 180°, and the phase of the second planetary shaft center X3 is 0°. At this time, as viewed in the axial direction L, the first input shaft center X4 is located on the opposite side of the carrier shaft center X1 with respect to the first planetary shaft center X2, and the second input shaft center X5 is located on the opposite side of the carrier shaft center X1 with respect to the second planetary shaft center X3. As viewed in the axial direction L, the first input shaft center X4, the first planetary shaft center X2, the carrier shaft center X1, the second planetary shaft center X3, and the second input shaft center X5 are aligned on a straight line.

[0062] Note that, although a description of the process until the phase of the first planetary shaft center X2 becomes 0° will be omitted, as described above, the first input member 3 and the second input member 5 perform reciprocating motion so that the first input shaft center X4 and the second input shaft center X5 describe an elliptical locus T1.

[0063] 14, in this embodiment, the configuration of the bicycle B equipped with the power conversion device 100 is different from that of the first embodiment. Specifically, in this embodiment, the bicycle B further includes a generator G and a motor (not shown). A transmission mechanism T is configured to transmit the rotation of the output member 6 of the power conversion device 100 to the generator G.

[0064] In this embodiment, the transmission mechanism T includes a fifth sprocket SP5 and a third chain CH3 instead of the second sprocket SP2, the third sprocket SP3, the fourth sprocket SP4, the first chain CH1, and the second chain CH2.

[0065] The fifth sprocket SP5 is connected to the rotor of the generator G so as to rotate integrally with the rotor. The third chain CH3 is wound around the first sprocket SP1 and the fifth sprocket SP5. In the example shown in Figure 14, the fifth sprocket SP5 has a smaller diameter than the first sprocket SP1.

[0066] The generator G is configured to generate electricity using the driving force transmitted via the transmission mechanism T and store the electricity in an electricity storage device (not shown). The motor receives power from the electricity storage device to power the motor and drive the drive wheels W1.

[0067] 3. Third Embodiment A power conversion device 100 according to a third embodiment will be described below with reference to FIG. 15 . In this embodiment, the configuration of the planetary gear mechanism 1 is different from that of the first embodiment. The following description will focus on the differences from the first embodiment. Note that points that are not specifically described are the same as those in the first embodiment.

[0068] 15, in this embodiment, the planetary gear mechanism 1 further includes a third planetary gear PG3 and a sun gear SG. Note that in this embodiment, the planetary gear mechanism 1 does not include a second ring gear RG2.

[0069] The third planetary gear PG3 is disposed on the first planetary axis X2 at a different position in the axial direction L from the first planetary gear PG1. The third planetary gear PG3 is connected to the first planetary gear PG1 so as to rotate integrally with it. In this embodiment, the third planetary gear PG3 is disposed on the second axial side L2 relative to the first planetary gear PG1. The third planetary gear PG3 is connected to the first planetary shaft PS1 so as to rotate integrally with it.

[0070] In this embodiment, the first planetary shaft PS1 is disposed so as to penetrate the first planetary gear PG1 and the third planetary gear PG3 in the axial direction L. The first planetary shaft PS1 is rotatably supported with respect to the carrier CR via a pair of first planetary bearings B1 that are disposed separately on a first axial side L1 relative to the first planetary gear PG1 and a second axial side L2 relative to the third planetary gear PG3.

[0071] The sun gear SG is disposed on the carrier axis X1. The sun gear SG is in mesh with the second planetary gear PG2 and the third planetary gear PG3. In this embodiment, the sun gear SG is rotatably supported by the carrier CR via a sun gear bearing B6 disposed radially inward of the sun gear SG.

[0072] In this embodiment, the radius r4 of the second planetary gear PG2 and the radius r5 of the third planetary gear PG3 are the same. That is, the second planetary gear PG2 and the third planetary gear PG3 have the same diameter. Furthermore, the radius r4 of the second planetary gear PG2 and the radius r5 of the third planetary gear PG3 are each smaller than the radius r2 of the first planetary gear PG1. That is, the second planetary gear PG2 and the third planetary gear PG3 are each smaller in diameter than the first planetary gear PG1.

[0073] In this embodiment, the ring gear RG is fixed to a first ring gear support portion RS1 and a second ring gear support portion RS2. The first ring gear support portion RS1 is disposed on a first axial side L1 relative to the ring gear RG. The first ring gear support portion RS1 rotatably supports the carrier CR from the outside in the radial direction R via a first ring gear bearing B4. The second ring gear support portion RS2 is disposed on a second axial side L2 relative to the ring gear RG. The second ring gear support portion RS2 rotatably supports the carrier CR from the outside in the radial direction R via a second ring gear bearing B5.

[0074] In this embodiment, the first planetary bearing B1 on the first axial side L1, the second planetary bearing B2 on the first axial side L1, and the first ring gear bearing B4 are arranged so that their arrangement areas in the axial direction L overlap each other. Furthermore, the first planetary bearing B1 on the second axial side L2, the second planetary bearing B2 on the second axial side L2, and the second ring gear bearing B5 are arranged so that their arrangement areas in the axial direction L overlap each other. This makes it possible to keep the dimension of the planetary gear mechanism 1 in the axial direction L small, and ultimately to reduce the size of the power conversion device 100 in the axial direction L.

[0075] 4. Other Embodiments (1) In the above embodiment, an example has been described in which the first input member 3 is a shaft member fixed to the first crank member 2, and the second input member 5 is a shaft member fixed to the second crank member 4. However, the present invention is not limited to such a configuration. For example, a configuration may be adopted in which a shaft member as the first input member 3 and a shaft member as the second input member 5 are not provided, and a part of the first crank member 2 functions as the first input member 3 and a part of the second crank member 4 functions as the second input member 5.

[0076] (2) In the above embodiment, the first planetary shaft center X2 and the second planetary shaft center X3 are arranged with a phase difference of 180°. However, the present invention is not limited to such a configuration, and the first planetary shaft center X2 and the second planetary shaft center X3 may be arranged with a phase difference other than 180°.

[0077] (3) In the above embodiment, an example has been described in which there is a phase in which the first input shaft center X4, the first planetary shaft center X2, the carrier shaft center X1, the second planetary shaft center X3, and the second input shaft center X5 are aligned on a straight line on the locus T1 when viewed in the axial direction along the axial direction L. However, the present invention is not limited to such a configuration, and there may be a configuration in which there is no phase in which the first input shaft center X4, the first planetary shaft center X2, the carrier shaft center X1, the second planetary shaft center X3, and the second input shaft center X5 are aligned on a straight line on the locus T1 when viewed in the axial direction along the axial direction L.

[0078] (4) In the above embodiment, the first crank member 2 and the second crank member 4 are arranged so that the direction along the line passing through the first planetary axis X2 and the first input axis X4 (the direction along which the first crank member 2 extends) and the direction along the line passing through the second planetary axis X3 and the second input axis X5 (the direction along which the second crank member 4 extends) are parallel to each other. However, the present invention is not limited to this configuration, and the first crank member 2 and the second crank member 4 may be arranged so that the direction of extension thereof intersects with each other.

[0079] (5) In the above embodiment, the first ring gear RG1 and the second ring gear RG2 have the same diameter. However, the present invention is not limited to this configuration, and the first ring gear RG1 and the second ring gear RG2 may have different diameters.

[0080] (6) Note that the configurations disclosed in the above-described embodiments can be applied in combination with configurations disclosed in other embodiments, as long as no contradictions arise. Regarding other configurations, the embodiments disclosed in this specification are merely examples in all respects. Therefore, various modifications can be made as appropriate within the scope of the present disclosure.

[0081] 5. Summary of the Present Embodiment The power conversion device (100) described above will now be outlined.

[0082] The power conversion device (100) includes: a planetary gear mechanism (1) including a ring gear (RG) that is a fixed internal gear, a first planetary gear (PG1) that meshes with the ring gear (RG), a second planetary gear (PG2) that is arranged on an axis separate from that of the first planetary gear (PG1), and a carrier (CR) that rotatably supports the first planetary gear (PG1) and the second planetary gear (PG2); a first crank member (2) that is arranged to extend in a first planetary radial direction (Rp1) that is perpendicular to a first planetary axis (X2) that is the rotation axis of the first planetary gear (PG1) and is connected to the first planetary gear (PG1) so as to rotate integrally with the first planetary gear (PG1); a first input member (3) supported by the first crank member (2) and disposed on a first input shaft center (X4) spaced apart from the first planetary axis center (X2) in the first planetary radial direction (Rp1); a second crank member (4) disposed so as to extend in a second planetary radial direction (Rp2) perpendicular to a second planetary axis center (X3) which is the rotational axis of the second planetary gear (PG2) and connected to the second planetary gear (PG2) so as to rotate integrally with the second planetary gear (PG2); and a second input member (5) supported by the second crank member (4) and disposed on a second input shaft center (X5) spaced apart from the second planetary axis center (X3) in the second planetary radial direction (Rp2). an output member (6) connected to a specific rotating member (RT) that rotates in conjunction with the carrier (CR), excluding the first planetary gear (PG1) and the second planetary gear (PG2), wherein the radius (r1) of the ring gear (RG) is twice the radius (r2) of the first planetary gear (PG1); an axial direction (L) is a direction along a carrier axis (X1) that is the rotation axis of the carrier (CR), and the first planetary gear (PG1) and the second planetary gear (PG2) are configured to revolve around the carrier axis (X1) at the same speed and in the same direction; when viewed in the axial direction along the axial direction (L), the first planetary axis (X2) and the second planetary axis (X3) are arranged on opposite sides of the carrier axis (X1) and at positions that are the same distance from the carrier axis (X1);The first crank member (2) is connected to the first planetary gear (PG1), and the second crank member (4) is connected to the second planetary gear (PG2) so that, when viewed in the axial direction, the first input shaft center (X4) and the second input shaft center (X5) are located on opposite sides of the carrier shaft center (X1).

[0083] According to this configuration, the movement loci (T1) of the first input shaft center (X4) and the second input shaft center (X5) accompanying the reciprocating motion of the first input member (3) and the second input member (5) can be linear or elliptical with respect to the carrier shaft center (X1). Furthermore, the phase difference between the first input shaft center (X4) and the second input shaft center (X5) can be set to 180° or a value close to that. Therefore, a power conversion device (100) can be realized that easily transmits driving force to the first input member (3) disposed on the first input shaft center (X4) and the second input member (5) disposed on the second input shaft center (X5).

[0084] Here, it is preferable that the planetary gear mechanism (1) further includes a second ring gear (RG2) that is a fixed internal gear in addition to a first ring gear (RG1) as the ring gear (RG), the second planetary gear (PG2) meshes with the second ring gear (RG2), and the radius (r3) of the second ring gear (RG2) is twice the radius (r4) of the second planetary gear (PG2).

[0085] This configuration makes it easy to make the drive force transmission structure from the first crank member (2) to the carrier (CR) similar to the drive force transmission structure from the second crank member (4) to the carrier (CR). Therefore, the power conversion device (100) can be easily configured simply. Furthermore, this configuration makes it easy to reduce the number of types of parts by using common components between the first ring gear (RG1) and the first planetary gear (PG1) and the second ring gear (RG2) and the second planetary gear (PG2) when the radius (r1) of the first ring gear (RG1) and the radius (r3) of the second ring gear (RG2) are the same.

[0086] Furthermore, the planetary gear mechanism (1) further includes a third planetary gear (PG3) that is arranged on the first planetary axis (X2) at a position different from the first planetary gear (PG1) in the axial direction (L) and is connected to rotate integrally with the first planetary gear (PG1), and a sun gear (SG) that is arranged on the carrier axis (X1), and it is preferable that a radius (r4) of the second planetary gear (PG2) and a radius (r5) of the third planetary gear (PG3) are the same, and the second planetary gear (PG2) and the third planetary gear (PG3) are meshed with the sun gear (SG).

[0087] According to this configuration, it is possible to appropriately realize a configuration in which the first planetary gear (PG1) and the second planetary gear (PG2) rotate at the same speed in the same direction.

[0088] It is also preferable that a distance (d1) between the first planetary axis center (X2) and the first input axis center (X4) in the first planetary radial direction (Rp1) is the same as a distance (d2) between the second planetary axis center (X3) and the second input axis center (X5) in the second planetary radial direction (Rp2), and that a radius (r2) of the first planetary gear (PG1) and the distance (d1) between the first planetary axis center (X2) and the first input axis center (X4) in the first planetary radial direction (Rp1) are different.

[0089] According to this configuration, the movement loci (T1) of the first input shaft center (X4) and the second input shaft center (X5) accompanying the reciprocating motion of the first input member (3) and the second input member (5) can be made elliptical with the carrier shaft center (X1) as the center. Furthermore, according to this configuration, if the distance (d1) between the first planet shaft center (X2) and the first input shaft center (X4) in the first planetary radial direction (Rp1) is made larger than the radius (r2) of the first planetary gear (PG1), it becomes easier to ensure a correspondingly large stroke of the reciprocating motion of the first input member (3) and the second input member (5). This facilitates the miniaturization of the planetary gear mechanism (1). Furthermore, according to this configuration, when the distance (d1) in the first planetary radial direction (Rp1) between the first planetary axis (X2) and the first input axis (X4) is made smaller than the radius (r2) of the first planetary gear (PG1), the directions of rotation (directions of elliptical movement) of the first input axis (X4) and the second input axis (X5) caused by the reciprocating motion of the first input member (3) and the second input member (5) can be made the same as the direction of rotation of the carrier (CR).

[0090] The technology according to the present disclosure can be used in a power conversion device that converts reciprocating motion into rotational motion.

[0091] 100: power conversion device, 1: planetary gear mechanism, RG: ring gear, RG1: first ring gear, RG2: second ring gear, PG1: first planetary gear, PG2: second planetary gear, PG3: third planetary gear, CR: carrier, SG: sun gear, 2: first crank member, 3: first input member, 4: second crank member, 5: second input member, 6: output member, RT: specific rotating member, X1: carrier axis, X2: first planetary axis, X3: second planetary axis, X4: first input axis, X5: second input axis, L: axial direction, Rp1: first planetary radial direction, Rp2: second planetary radial direction

Claims

1. A planetary gear mechanism including a ring gear which is a fixed internal gear, a first planetary gear meshing with the ring gear, a second planetary gear arranged on a separate axis from the first planetary gear, and a carrier which rotatably supports the first planetary gear and the second planetary gear; a first crank member arranged to extend in a first planetary radial direction perpendicular to a first planetary axis which is the rotation axis of the first planetary gear and connected to rotate integrally with the first planetary gear; a first input member supported by the first crank member and arranged on a first input axis spaced from the first planetary axis in the first planetary radial direction; a second crank member arranged to extend in a second planetary radial direction perpendicular to a second planetary axis which is the rotation axis of the second planetary gear and connected to rotate integrally with the second planetary gear; the second input member is supported by the second crank member and arranged on a second input shaft center spaced apart from the second planetary axis in the second planetary radial direction; and an output member is connected to a specific rotating member that rotates in conjunction with the carrier, excluding the first planetary gear and the second planetary gear, wherein the radius of the ring gear is twice the radius of the first planetary gear, the first planetary gear and the second planetary gear are configured to revolve around the carrier axis center at the same speed and in the same direction, with the axial direction being a direction along the carrier axis center that is the rotational axis center of the carrier, and the first planetary axis center and the second planetary axis center are arranged at positions on opposite sides of the carrier axis center and at the same distance from the carrier axis center as viewed in the axial direction, a power conversion device in which the first crank member is connected to the first planetary gear and the second crank member is connected to the second planetary gear so that, when viewed in the axial direction, the first input shaft center and the second input shaft center are located on opposite sides of the carrier shaft center.

2. The power conversion device as described in claim 1, wherein the planetary gear mechanism further comprises a second ring gear which is a fixed internal gear in addition to the first ring gear as the ring gear, the second planetary gear meshes with the second ring gear, and the radius of the second ring gear is twice the radius of the second planetary gear.

3. A power conversion device as described in claim 1, wherein the planetary gear mechanism further comprises a third planetary gear arranged on the first planetary axis at a different axial position from the first planetary gear and connected to rotate integrally with the first planetary gear, and a sun gear arranged on the carrier axis, wherein the radius of the second planetary gear and the radius of the third planetary gear are the same, and the second planetary gear and the third planetary gear mesh with the sun gear.

4. A power conversion device as described in any one of claims 1 to 3, wherein the distance in the first planetary radial direction between the first planetary shaft center and the first input shaft center is the same as the distance in the second planetary radial direction between the second planetary shaft center and the second input shaft center, and the radius of the first planetary gear and the distance in the first planetary radial direction between the first planetary shaft center and the first input shaft center are different.

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