JP5091692B2 - Transmission with planetary gear mechanism - Google Patents

Description

  The present invention relates to a transmission with a planetary gear mechanism.

  As a vehicle transmission (reduction gear), a transmission with a planetary gear mechanism is used. In this transmission, a sun gear, a carrier (planetary gear), and a ring gear, which are components of a planetary gear mechanism, are arranged in a case. One of these components is fixed to the case, one is connected to the input side, and one is connected to the output side.

  When the ring gear is fixed to the case, it is necessary to suppress transmission of gear sound and vibration using the ring gear as a vibration source to the case. As measures for this, (1) changing the target value of the tooth profile of the ring gear and (2) improving the tooth surface finish can be considered. However, feed processing using a gear shaper, which is a ring gear manufacturing method when mass production is assumed, is currently inaccurate and (1) it is difficult to change the target value of the tooth profile of the ring gear. The ring gear is an internal gear, and (2) it is difficult to improve the tooth surface finish.

Therefore, in Patent Document 1, in a transmission incorporating a planetary gear mechanism having an element to be fixed to the transmission case, vibration is transmitted to the transmission case by fixing the fixing element to the cylinder portion of the hydraulic brake. Techniques for suppression are described. Patent Document 2 describes a technique in which an intermediate member is interposed between one case of a planetary gear mechanism fixed to the case side and the case, and this intermediate member is splined to the case side and each of the elements. Has been. As a result, the meshing excitation force generated by the meshing of the gears generated by the planetary gear mechanism is attenuated by minute elastic deformation of the inner and outer teeth of the intermediate member, thereby suppressing vibration transmission from the planetary gear mechanism to the case. It is stated that it will be possible.
JP 2001-221328 A JP 2005-16635 A

However, in the techniques described in Patent Documents 1 and 2, it is necessary to increase the radial length of the intermediate member in order to increase the effect of suppressing vibration transmission. In this case, there is a problem that the planetary gear mechanism is enlarged.
Therefore, an object of the present invention is to provide a transmission with a planetary gear mechanism that can suppress an increase in size while suppressing vibration transmission from a ring gear to a case.

In order to solve the above problems, the invention according to claim 1 is directed to a planetary gear mechanism (for example, the planetary gear mechanism 12 in the embodiment) and a ring gear (for example, the ring gear 24 in the embodiment) as a case (for example, the case 11 in the embodiment). ) Fixed with a planetary gear mechanism (for example, the transmission 10 in the embodiment), and coaxially with the ring gear and the case between the ring gear and the case, from the ring gear and the case An intermediate member (for example, the intermediate member 40 in the embodiment) is disposed with a gap (for example, the gaps 42 and 44 in the embodiment) in the radial direction, and the intermediate member is a first contact portion (for example, the first member in the embodiment). The first contact portion 50) can be brought into contact with the ring gear, and the second contact portion (for example, the embodiment) Is contactable to said casing at a second contact portion 60) in said first contact portion and the second contact portion, the are arranged at different positions in the circumferential direction of the intermediate member, with the second contact portion, A second convex portion (for example, the second convex portion 62 in the embodiment) is formed on the outer peripheral surface of the intermediate member, and a second concave portion (for example, the second concave portion 64 in the embodiment) is formed on the inner peripheral surface of the case. The side surface of the second convex portion (for example, the side surface 62a in the embodiment) in the circumferential direction of the intermediate member can be brought into contact with the side surface of the second concave portion (for example, the side surface 64a in the embodiment). A depression (for example, a depression 63 in the embodiment) is formed on the tip surface of the second protrusion .

  According to a second aspect of the present invention, in the first contact portion, a first convex portion (for example, the first convex portion 52 in the embodiment) is formed on the outer peripheral surface of the ring gear, and the inner peripheral surface of the intermediate member. The first concave portion (for example, the first concave portion 54 in the embodiment) is formed, and the side surface of the first convex portion (for example, the side surface 52a in the embodiment) and the side surface of the first concave portion in the circumferential direction of the intermediate member ( For example, the embodiment is characterized in that the side surface 54a) in the embodiment can be brought into contact.

  In the invention according to claim 3, both side surfaces of the first convex portion in the circumferential direction of the intermediate member are planes including a central axis of the intermediate member and a central point of the first convex portion (for example, a plane in the embodiment). S) and is formed in parallel.

The invention according to claim 4 is a clearance fit between the side surface of the first convex portion and the side surface of the first concave portion, and between the side surface of the second convex portion and the side surface of the second concave portion. It is characterized by being fitted.

According to a fifth aspect of the present invention, there is an interference fit between the side surface of the first convex portion and the side surface of the first concave portion, or between the side surface of the second convex portion and the side surface of the second concave portion. It is characterized by being press-fitted.

According to the first aspect of the invention, since the first contact portion and the second contact portion are arranged at different positions in the circumferential direction of the intermediate member, it is possible to ensure a vibration transmission distance from the ring gear to the case. Therefore, vibration transmission can be suppressed by attenuating vibration. Thus, instead of securing the vibration transmission distance in the radial direction of the intermediate member, securing the vibration transmission distance in the circumferential direction can suppress vibration transmission without increasing the size of the transmission.
When a convex part is formed on the case, a corresponding concave part is formed on the ring gear.
On the other hand, according to the first aspect of the present invention, since it is not necessary to form a recess in the ring gear, it is easy to ensure the strength of the ring gear. Along with this, it is possible to prevent the ring gear from becoming thick in the radial direction, and it is possible to prevent the transmission from becoming large.
Moreover, since the 2nd convex part is divided | segmented into the circumferential direction by the hollow part, the 2nd convex part becomes easy to bend in the circumferential direction. Thereby, vibration transmission from the intermediate member to the case can be effectively suppressed.

  According to the invention which concerns on Claim 2, compared with the case where a recessed part is formed in a ring gear, it becomes easy to ensure the intensity | strength of a ring gear. Along with this, it is possible to prevent the ring gear from becoming thick in the radial direction, and it is possible to prevent the transmission from becoming large.

  As in the invention according to claim 3, by forming the first convex portion in a rectangular tooth shape, the torque acting on the ring gear can be reliably transmitted by the intermediate member, and the rattling of the ring gear is suppressed. can do.

According to the invention which concerns on Claim 4 , the assembly operation | work of a ring gear, an intermediate member, and a case can be performed easily.

According to the invention which concerns on Claim 5 , shakiness of a ring gear, an intermediate member, and a case can be suppressed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic configuration diagram showing a layout of a vehicle. A transmission 10 with a planetary gear mechanism according to the present invention is used, for example, in a drive device 1 of a vehicle 3 shown in FIG. A vehicle 3 shown in FIG. 1 is a hybrid vehicle having a drive unit 6 in which an internal combustion engine 4 and an electric motor 5 are connected in series. The power of the drive unit 6 is transmitted to the front wheel Wf side via a transmission 7. On the other hand, the power of the drive device 1 provided separately from the drive unit 6 is transmitted to the rear wheel Wr side. The electric motor 5 of the driving unit 6 on the front wheel Wf side and the electric motor 2 of the driving device 1 on the rear wheel Wr side are connected to the battery 9 via a PDU 8 (power drive unit). The power supply from the battery 9 to the electric motors 5 and 2 and the energy regeneration from the electric motors 5 and 2 to the battery 9 are performed via the PDU 8.

  FIG. 2 is an explanatory diagram of the transmission with a planetary gear mechanism according to the present embodiment, and is a cross-sectional view taken along line YY in FIGS. 1 and 3. As shown in FIG. 2, the transmission 10 with a planetary gear mechanism according to the present embodiment is configured such that a sun gear 21, a planetary gear 22, and a ring gear 24 that are components of the planetary gear mechanism 12 are arranged inside the case 11. ing.

  3 is a cross-sectional view taken along line ZZ in FIG. As shown in FIG. 3, the planetary gear mechanism-equipped transmission 10 includes a sun gear 21 integrally provided on the outer periphery of one end of the cylindrical shaft 16, a plurality of planetary gears 22 meshed with the sun gear 21, and these planetary gears 22. And a ring gear 24 that meshes with the outer peripheral side of the planetary gear 22. Then, the driving force of an electric motor (not shown) is input to the sun gear 21, and the reduced driving force is output through the planetary carrier 23.

  The planetary gear 22 has a large-diameter first gear 26 that is directly meshed with the sun gear 21 and a second gear 27 that is smaller in diameter than the first gear 26. The first gear 26 and the second gear 27 are It is integrally formed in a state that is coaxial and offset in the axial direction. The ring gear 24 is fixedly installed at a position facing the axial side surface of the first gear 26, and the inner peripheral surface of the ring gear 24 is engaged with the second gear 27 having a small diameter. In the case of this embodiment, the maximum radius of the ring gear 24 is set to be smaller than the maximum distance of the first gear 26 from the center of the axle 10B.

On the other hand, the differential 13 includes a differential case 31 with a rotatable pinion 30 projecting on the inner surface side, and a pair of side gears 32a and 32b meshed with the pinion 30 in the differential case 31. Side gears 32a and 32b are coupled to the left and right axles 10A and 10B, respectively. A planetary carrier 23 of the planetary gear mechanism 12 is integrally coupled to the differential case 31. The differential case 31 is rotatably supported in the case 11.
When the electric motor (not shown) is started when the vehicle starts, the driving force of the electric motor is reduced to the set reduction ratio by the planetary gear mechanism 12 and further transmitted to the left and right axles 10A and 10B via the differential device 13. It has come to be.

(Intermediate member)
Returning to FIG. 2, the intermediate member 40 is disposed between the ring gear 24 and the case 11 so as to be coaxial with the ring gear 24 and the case 11. The intermediate member 40 is formed in a substantially ring shape from a hardened iron alloy material or the like. The intermediate member 40 is disposed with a gap 42 in the radial direction from the ring gear 24, and is disposed with a gap 44 in the radial direction from the case 11. The intermediate member 40 is uniformly formed in the axial direction.

  The intermediate member 40 can be brought into contact with the ring gear 24 at the first contact portion 50, and can be brought into contact with the case 11 at the second contact portion 60. The first contact portions 50 and the second contact portions 60 are alternately arranged at different positions in the circumferential direction of the intermediate member 40, specifically, for each predetermined angle. In the region excluding the first contact portion 50 and the second contact portion 60, the intermediate member 40 is disposed with gaps 42 and 44 in the radial direction from the ring gear 24 and the case 11.

  FIG. 4 is a partially enlarged view of FIG. As shown in FIG. 4, in the first contact portion 50, a first convex portion 52 is formed from the outer peripheral surface of the ring gear 24 toward the radially outer side. Both side surfaces 52 a of the first convex portion 52 in the circumferential direction of the ring gear 24 are disposed substantially parallel to the plane S including the central axis of the intermediate member 40 and the central point of the first convex portion 52. That is, the 1st convex part 52 is formed in the rectangular tooth shape. A plurality of (eight in the present embodiment) first convex portions 52 are formed at predetermined angles in the circumferential direction of the ring gear 24.

  In the first contact portion 50, a first concave portion 54 is formed from the inner peripheral surface of the intermediate member 40 toward the radially outer side so as to face the first convex portion 52 described above. Both side surfaces 52a of the first convex portion 52 and both side surfaces 54a of the first concave portion 54 in the circumferential direction of the intermediate member 40 can be brought into contact with each other. On the other hand, a gap 42 b is provided between the front end surface 52 b of the first convex portion 52 and the bottom surface 54 b of the first concave portion 54.

  Since the intermediate member 40 of the present embodiment is formed thin, a convex portion 56 corresponding to the first concave portion 54 is formed on the outer peripheral surface of the intermediate member 40. A concave portion 58 is formed on the inner peripheral surface of the case 11 corresponding to the convex portion 56. A gap 44 provided between the intermediate member 40 and the case 11 extends between the convex portion 56 and the concave portion 58.

On the other hand, in the second contact portion 60, a second convex portion 62 is formed from the outer peripheral surface of the intermediate member 40 toward the radially outer side. Both side surfaces 62a of the second convex portion 62 in the circumferential direction of the intermediate member 40 are inclined surfaces whose normal lines are directed outward in the radial direction. That is, the 2nd convex part 62 is formed in trapezoid tooth shape. A plurality (eight in this embodiment) of second convex portions 62 are formed at predetermined angles in the circumferential direction of the intermediate member 40.
In addition, the recessed part 63 is formed toward the radial inside from the circumferential direction center part of the front end surface 62b of the 2nd convex part 62. As shown in FIG. The second convex portion 62 is divided into two in the circumferential direction by the hollow portion 63.

  In the second contact portion 60, a second concave portion 64 is formed from the inner peripheral surface of the case 11 toward the outer side in the radial direction so as to face the above-described second convex portion 62. Both side surfaces 62a of the second convex portion 62 and both side surfaces 64a of the second concave portion 64 in the circumferential direction of the intermediate member 40 can be brought into contact with each other. On the other hand, a gap 44 b is provided between the tip surface 62 b of the second convex portion 62 and the bottom surface 64 b of the second concave portion 64.

  Fitting between the side surface 52a of the first convex portion 52 and the side surface 54a of the first concave portion 54 and between the side surface 62a of the second convex portion 62 and the side surface 64a of the second concave portion 64 is a clearance fit. Or may be press-fitted so as to have a tight fit. When fitting so as to be a clearance fit, the assembly work of the ring gear 24, the intermediate member 40, and the case 11 can be easily performed. In this case, the driving torque (or regenerative torque in the reverse direction) acts on the ring gear 24, so that the side surface 52a of the first convex portion 52 and the side surface 54a of the first concave portion 54 abut and the second convex portion. The side surface 62a of 62 and the side surface 64a of the 2nd recessed part 64 contact | abut. On the other hand, when it is press-fitted so as to be tightly fitted, it is possible to suppress the rattling of the ring gear in the circumferential direction, and it is possible to reduce the occurrence of shock and noise when the vehicle starts.

(Function)
Next, the operation of the above-described transmission with a planetary gear mechanism will be described with reference to FIG.
Vibrations such as gear noise generated in the ring gear 24 are transmitted to the case 11 via the intermediate member 40. Since a gap 42 is provided between the ring gear 24 and the intermediate member 40 and both can be brought into contact with each other only by the first contact portion 50, vibration is generated from the ring gear 24 to the intermediate member 40 at the first contact portion 50. Communicated. In the first contact portion 50, the side surface 52 a of the first convex portion 52 of the ring gear 24 and the side surface 54 a of the first concave portion 54 of the intermediate member 40 come into contact with each other, and vibration is transmitted in the circumferential direction. Here, since the 1st convex part 52 is protrudingly formed from the outer peripheral surface of the ring gear 24, it can be bent and deform | transformed in the circumferential direction although it is minute, and it can attenuate a vibration. Therefore, vibration transmission from the ring gear 24 to the intermediate member 40 can be suppressed.

Further, a gap 44 is provided between the intermediate member 40 and the case 11, and both can be brought into contact with each other only by the second contact portion 60, so that the intermediate member 40 is moved from the intermediate member 40 to the case 11 at the second contact portion 60. Vibration is transmitted. In the second contact portion 60, the side surface 62a of the second convex portion 62 of the intermediate member 40 and the side surface 64a of the second concave portion 64 of the case 11 come into contact with each other, and vibration is transmitted in the circumferential direction. Here, since the 2nd convex part 62 is protrudingly formed from the intermediate member 40, it can be bent and deform | transformed in the circumferential direction although it is minute, and it can attenuate a vibration. Therefore, vibration transmission from the intermediate member 40 to the case 11 can be effectively suppressed.
In addition, since the 2nd convex part 62 is divided into the circumferential direction by the hollow part 63 formed in the front end surface of the 2nd convex part 62, the 2nd convex part 62 is easy to bend in the circumferential direction. Thereby, vibration transmission from the intermediate member 40 to the case 11 can be effectively suppressed.

The first contact part 50 and the second contact part 60 are arranged at different positions in the circumferential direction of the intermediate member 40. As a result, it is possible to ensure a vibration transmission distance from the ring gear 24 to the case 11 and to attenuate the vibration. Particularly in this embodiment, since the intermediate member 40 is formed thin between the first contact portion 50 and the second contact portion 60, the intermediate member 40 can be freely deformed to effectively attenuate the vibration. Can do. Moreover, since the vibration transmission distance is secured in the circumferential direction instead of securing the vibration transmission distance in the radial direction of the intermediate member, the outer shape of the case 11 can be prevented from being enlarged.
If the quietness required for a transmission with a planetary gear mechanism differs due to differences in the vibration isolation performance of the vehicle, etc., it is possible to cope with low cost by sharing the case and changing the ring gear and plate. It is.

In the first contact portion 50, since the first convex portion 52 is formed in the ring gear 24 and the first concave portion 54 is formed in the intermediate member 40, the strength of the ring gear 24 is secured as compared with the case where the concave portion is formed in the ring gear. It becomes easy. Along with this, it is possible to prevent the ring gear 24 from being thickened in the radial direction, and the case 11 can be prevented from being enlarged.
Further, in the second contact portion 60, when a convex portion is formed on the case and a concave portion is formed on the intermediate member, the concave portion corresponding to the ring gear is also formed, contrary to the present embodiment. On the other hand, in the present embodiment, since the second convex portion 62 is formed on the intermediate member 40 and the second concave portion 64 is formed on the case 11, it is not necessary to form the concave portion on the ring gear, and the strength of the ring gear 24 is ensured. It becomes easy. Along with this, it is possible to prevent the ring gear 24 from being thickened in the radial direction, and the case 11 can be prevented from being enlarged.

  In the present embodiment, since the first convex portion of the ring gear 24 is fitted in the first concave portion 54 of the intermediate member 40, there is almost no gap in the circumferential direction of the intermediate member 40. Thereby, even when torque is input to the intermediate member 40, it is possible to prevent the intermediate member 40 from being greatly deformed, and the ring gear 24 can be reliably fixed to the case 11.

In addition, this invention is not limited to said embodiment, A various design change is possible in the range which does not deviate from the summary. For example, the transmission with a planetary gear mechanism according to the present invention can be applied to a vehicle that employs a drive system other than the drive system shown in FIG.
Moreover, as shown in FIG. 4, although the 1st convex part 52 was formed in the rectangular tooth shape and the 2nd convex part 62 was formed in the trapezoid tooth shape in the said embodiment, you may form in shapes other than these.
Moreover, as shown in FIG. 2, in the said embodiment, although the 1st contact part 50 and the 2nd contact part 60 were arrange | positioned at equal intervals in the circumferential direction of an intermediate member, you may arrange | position at unequal intervals.

  FIG. 5 is an explanatory diagram of a modified example of the intermediate member. As shown in FIG. 5, the intermediate member 40 may be divided and formed in the axial direction. Specifically, the intermediate member 40 may be formed by laminating a plurality of divided pieces 41a with a resin adhesive 41b or the like. In this case, the manufacturing cost of the intermediate member 40 can be reduced.

It is a schematic block diagram which shows the layout of a vehicle. It is explanatory drawing of the planetary gear mechanism which concerns on embodiment, and is sectional drawing in the YY line of FIG. It is sectional drawing in the ZZ line | wire of FIG. FIG. 4 is a partially enlarged view of FIG. 3. It is explanatory drawing of the modification of an intermediate member.

Explanation of symbols

  S ... plane 10 ... transmission 11 ... case 12 ... planetary gear mechanism 24 ... ring gear 40 ... intermediate member 42 ... gap 44 ... gap 50 ... first contact portion 52 ... first convex portion 52a ... side surface 54 ... first concave portion 54a ... Side surface 60 ... second contact portion 62 ... second convex portion 62a ... side surface 63 ... concave portion 64 ... second concave portion 64a ... side surface

Claims (5)

A planetary gear mechanism-equipped transmission in which a ring gear of a planetary gear mechanism is fixed to a case,
An intermediate member is disposed between the ring gear and the case coaxially with the ring gear and the case, with a gap in the radial direction from the ring gear and the case,
The intermediate member can be brought into contact with the ring gear at the first contact portion, and can be brought into contact with the case at the second contact portion,
The first contact portion and the second contact portion are arranged at different positions in the circumferential direction of the intermediate member ,
In the second contact portion, a second convex portion is formed on the outer peripheral surface of the intermediate member, and a second concave portion is formed on the inner peripheral surface of the case. The second convex portion in the circumferential direction of the intermediate member And the side surface of the second recess can be contacted,
A transmission with a planetary gear mechanism , wherein a recess is formed on a tip surface of the second convex portion .   In the first contact portion, a first convex portion is formed on the outer peripheral surface of the ring gear, and a first concave portion is formed on the inner peripheral surface of the intermediate member. The first convex portion in the circumferential direction of the intermediate member The transmission with a planetary gear mechanism according to claim 1, wherein a side surface of the first recess portion and a side surface of the first recess can be brought into contact with each other.   The both side surfaces of the first convex portion in the circumferential direction of the intermediate member are formed in parallel to a plane including a central axis of the intermediate member and a central point of the first convex portion. A transmission with a planetary gear mechanism according to 1. The side surface of the first convex portion and the side surface of the first concave portion, and the side surface of the second convex portion and the side surface of the second concave portion are fitted so as to be a clearance fit. The transmission with a planetary gear mechanism according to claim 2 or claim 3 , wherein Between the side surface of the first convex portion and the side surface of the first concave portion or between the side surface of the second convex portion and the side surface of the second concave portion is press-fitted so as to be an interference fit. The transmission with a planetary gear mechanism according to claim 2 or 3 , characterized by the above-mentioned.

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