JP2009156340A - Differential device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance a torque bias ratio (TBR) during coasting compared with one during driving by a simple structure. <P>SOLUTION: The differential device is provided with: first and second storage holes 43, 45 having shaft cores parallel with a rotating shaft of a differential case 3 where drive input is performed and short and long in the axial direction, respectively; first and second helical pinion gears 9, 11 axially rotatably stored and held in the first and second storage holes 43, 45, engaged with each other on one side in the axial direction and short and long in the axial direction; and a pair of helical side gears 5, 7 rotatably and concentrically arranged within the differential case 3 so as to face each other and engaged with the other sides in the axial direction of the first and second helical pinion gears 9 11, respectively, to perform drive output. The axially short first helical pinion gear 9 is arranged on the front side in the rotating direction during driving when the differential case 3 receives the drive input and is rotated, and the axially long second helical pinion gear 11 is arranged on the rear side in the rotating direction. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a differential apparatus using a helical gear of an automobile or the like.

  As a conventional differential device of this type, for example, there is a device described in Patent Document 1.

  This differential device supports a pair of helical side gears in the differential case so as to face each other in the axial direction, and is arranged in parallel in the circumferential direction on the outer periphery of the helical side gear and is relatively short in the axial direction. A pair of helical pinion gears, one of the helical pinion gears meshes with one of the pair of helical side gears and the other meshes with the other of the pair of helical side gears. It has a configuration.

  The pair of helical pinion gears is arranged with a first helical pinion gear that is long in the axial direction on the front side in the rotational direction when the case is rotated by receiving the driving input, and axially on the rear side in the rotational direction. A short second helical pinion gear is arranged.

  A thrust washer is interposed between the differential case and the helical side gear.

  When the differential case is rotated by a driving torque or the like during driving, each gear receives a thrust reaction force and a radial reaction force, and a differential limiting force can be obtained by a frictional force against the accommodation hole.

  By the way, in recent years, the output of the engine tends to be high power, and the demand for increasing the stability of the full brake at the time of cornering is increasing more and more.

  In response to this requirement, the TBR (torque / bias / ratio) during driving is driven by increasing the washer, increasing the coast side tooth surface, increasing the coast side pressure angle, and adding friction members such as friction clutches. It is possible to take countermeasures by raising it.

  However, such countermeasures require parts such as special washers and gears whose friction coefficient and pressure angle are changed, which complicates assembly and parts management, and may increase costs.

See JP-A-7-3317878

  The problem to be solved is that if the TBR (torque / bias / ratio) at the time of coasting is increased from that at the time of driving by adding friction members such as friction clutches, special parts are required, and assembly and parts management are required. Is complicated and may increase the cost.

  The present invention has a simple structure, a differential case in which drive input is performed, and a differential case within the differential case in order to make it possible to increase the torque bias ratio (TBR) during coasting compared to during driving. A relatively short axially long first and second receiving hole having an axis parallel to the rotation axis of the differential case, and the first and second receiving holes are rotatably held and held together. A relatively short axial first and second helical pinion gear that meshes with the first and second helical pinion gears concentrically and rotatably disposed in the differential case. A first helical pinion that is short in the axial direction on the front side in the rotational direction at the time of driving when the differential case is rotated by receiving the driving input. Place the gear and rotate The most important feature in that a long second helical pinion gear in the axial direction in the direction of the rear side.

  The present invention provides a first case and a second case that are relatively short in the axial direction and have a differential case in which drive input is performed, and an axial core that is formed in the differential case and is parallel to the rotational axis of the differential case. A first axially elongated first and second helical pinion gears that are rotatably held in the first and second receiving holes and mesh with each other, and concentric in the differential case And a pair of helical output gears that mesh with each of the first and second helical pinion gears to perform drive output, and the differential case receives drive input. The first helical pinion gear that is short in the axial direction is disposed on the front side in the rotational direction during the rotating drive, and the second helical pinion gear that is long in the axial direction is disposed on the rear side in the rotational direction.

  For this reason, the torque bias ratio (TBR) at the time of coasting can be increased more than at the time of driving with a simple structure by simply changing the arrangement of the short first and second helical pinion gears.

  The purpose of increasing the torque bias ratio (TBR) during coasting with a simple structure than during driving is realized by changing the arrangement of the first and second helical pinion gears with different axial lengths. did.

[Differential equipment]
FIG. 1 is a schematic perspective view of a differential device according to an embodiment of the present invention with a part cut away, FIG. 2 is a perspective view of a gear set with a differential case omitted, and FIG. 3 is a cross-sectional view of the differential device.

  The differential device 1 of FIG. 1 is used as, for example, a rear differential device, and is configured such that engine driving force is transmitted to a transmission, a propeller shaft, a differential device 1, a rear axle, and left and right rear wheels. .

  The differential device 1 is disposed in a differential carrier, and a driving force is input to the differential case 3 from the propeller shaft side by the meshing of the ring gear and the drive pinion gear. Yes.

  As shown in FIGS. 1 to 3, the helical side gears 5 and 7 are the same as a pair of helical output gears that are hollow inside the differential case 3 and have the same angle of twist in opposite directions. It is arranged in a core shape so as to be rotatable. On the outer periphery of the helical side gears 5 and 7, a pair of first and second helical pinions that are relatively short in the axial direction as a pinion gear set meshing with each other with the same twist angle in opposite directions. -Gears 9 and 11 are juxtaposed in the circumferential direction. The first and second helical pinion gears 9 and 11 are arranged in a plurality of pairs, for example, four pairs at equal intervals around the outer periphery of the helical side gears 5 and 7 in the circumferential direction. However, the plurality of pairs of the first and second helical pinion gears 9 and 11 may be arranged at unequal intervals in the circumferential direction.

  The first and second helical pinion gears 9 and 11 are arranged with a first helical pinion gear 9 that is short in the axial direction on the front side in the rotational direction when the differential case 3 is rotated by receiving a driving input. In addition, a second helical pinion gear 11 that is long in the axial direction is arranged on the rear side in the rotational direction.

  As shown in FIGS. 1 and 3, a flange portion 13 for attaching a ring gear is formed on the outer peripheral portion of the differential case 3, and boss portions 19 and 21 are formed on the side wall portions 15 and 17. ing. Bearing support portions 23 and 25 are formed on the outer periphery of the end portions of the boss portions 19 and 21, and shaft through holes 27 and 29 are formed on the inner periphery.

  A gear housing portion 31 is formed at the axial center of the differential case 3, and gear support portions 33 and 35 are formed on both sides of the gear housing portion 31. The differential case 3 is provided with inner receiving surfaces 39 and 41 that are axially inward and continuous with the inner ends of the gear support portions 33 and 35 so as to circulate around the rotation axis.

  On the inner outer peripheral side of the differential case 3, a pair of first and second receiving holes 43, 45 that are relatively short in the axial direction adjacent to the inner receiving surfaces 39, 41 are adjacent to each other in the circumferential direction. A plurality of pairs of directions, for example, four pairs are formed. The first and second accommodation holes 43 and 45 have an axis that is parallel to the rotational axis of the differential case 3.

  The differential case 3 is formed with an opening 46 that communicates with the first accommodation hole 43 and openings 47, 48, and 49 that communicate with the second accommodation hole 45. The openings 46, 47, 48, and 49 allow lubricating oil to flow inside and outside the differential case 3. The side wall 15 is formed with an oil groove 51 that communicates between the shaft through hole 27 and the first accommodation hole 43, and the side wall 17 is formed with an oil groove 53 that communicates between the shaft through hole 29 and the second accommodation hole 45. Has been. The oil grooves 51 and 53 are for guiding lubricating oil. Spiral grooves 27 a and 29 a are formed in the shaft through holes 27 and 29.

  The first and second helical pinion gears 9 and 11 are accommodated and held in the first and second receiving holes 43 and 45 so as to be rotatable about the shaft, and the first and second helical pinion gears 9 and 11 are held. Has an axis parallel to the rotational axis of the differential case 3.

  The first helical pinion gear 9 is a gear portion 9a, 9b whose entire outer periphery is integrally continuous, and is formed in a short axial direction. The second helical pinion gear 11 is formed to be long in the axial direction, and gear portions 11a and 11b are formed on both sides in the axial direction so as to be continuous between the gear portions 11a and 11b. A shaft portion 11c having a diameter smaller than the tooth tip diameter is provided.

  The first and second helical pinion gears 9 and 11 mesh with each other at the gear portions 9a and 11a on one side in the axial direction.

  The gear housing 31 includes the pair of helical side gears 5 and 7 that mesh with the first and second helical pinion gears 9 and 11 and face each other in the rotational axis direction for driving output. Contained. The helical side gears 5 and 7 have gear portions 5a and 7a formed on the outer periphery, and inner splines 5b and 7b for shaft coupling formed on the inner periphery. The gear portion 5a of the helical side gear 5 is engaged with the gear portion 9b on the other axial side of the first helical pinion gear 9, and the gear portion 7a of the helical side gear 7 is engaged with the second helical pinion gear. The gear 11 meshes with the gear portion 11b on the other side in the axial direction. The inner splines 5b and 7b are spline-coupled to the axle-side coupling shaft that penetrates the shaft through holes 27 and 29.

  When the differential case 3 is rotated in one direction by the driving force during driving, the pair of helical side gears 5 and 7 receive a thrust force in the opposite direction (the direction of arrow A in FIG. 3). When the case 3 is rotated in the other direction by the driving torque at the time of coasting, the pair of helical side gears 5 and 7 receives the thrust force in the opposite direction (direction of arrow B in FIG. 3). Twist angles of the gear portions 9a, 9b, 11a, 11b of the two helical pinion gears 9, 11 and the gear portions 5a, 7a of the pair of helical side gears 5, 7 are set.

  In this case, the first and second helical pinion gears 9 and 11 are required to effectively act on the TBR in the radial meshing reaction force component described later of the first and second helical pinion gears 9 and 11. It is assumed that the meshing reaction force component in the radial direction is larger than the meshing reaction force component in the axial direction (thrust direction). For this reason, the torsion angles of the gear portions 9a, 9b, 11a, 11b and the gear portions 5a, 7a are limited to 45 ° and set to less than 45 °. Specification values of a helical gear that can be easily machined: a pressure angle of 20 to 25 ° and a helix angle of 20 to 35 ° may be used.

  Annular inner facing surfaces 55 and 57 and outer facing surfaces 59 and 61 are provided adjacent to the inner peripheral side of the tooth width direction ends of the gear portions 5a and 7a of the pair of helical side gears 5 and 7, respectively. Yes. The inner facing surfaces 55 and 57 are opposed to each other with a constant interval in the rotation axis direction. The outer facing surfaces 59 and 61 are formed on the opposite sides of the inner facing surfaces 55 and 57.

  On the helical side gears 5 and 7, fitting portions 67 and 69 are formed in a circular shape adjacent to the inner facing surfaces 55 and 57, respectively. The fitting portions 67 and 69 are fitted to the gear support portions 33 and 35 on the differential case 3 side.

  In the helical side gears 5 and 7, a connection fitting hole 73 and a connection fitting portion 75 are formed on the inner peripheral side of the inner facing surfaces 55 and 57, and are fitted together and supported.

A thrust bush 77 is disposed between the inner facing surfaces 55 and 57 of the pair of helical side gears 5 and 7.
[Driving force transmission]
When the driving force is transmitted to the differential case 3, it is output from the first and second helical pinion gears 9 and 11 to the axle side via the helical side gears 5 and 7, and left and right by the left and right axles. When the rear wheel is driven and differential rotation occurs between the left and right rear wheels, the left and right helical side gears 5 and 7 rotate in conjunction with each other, and the first and second helical pinion gears 9 and 11 Differential rotation is allowed by rotation, and the driving force of the engine is differentially distributed to the left and right wheels while allowing differential rotation.

  When the differential case 3 is rotated in one direction by the driving torque during driving, the pair of helical side gears 5 and 7 receive a thrust force in the opposite direction (arrow A direction).

  Therefore, the left and right helical side gears 5 and 7 are pressed by the thrust force against the inner receiving surfaces 39 and 41 on the differential case 3 side through the thrust washers 63 and 65. By this pressing, the helical side gears 5 and 7 and the inner receiving surfaces 39 and 41 slide and rotate through the thrust washers 63 and 65, and a differential limiting force can be obtained.

  At this time, the meshing sliding of the gear portions 5a, 7a, 11a, 11b of the helical side gears 5, 7 and the first and second helical pinion gears 9, 11 and the first and second helical pinion gears are performed. The differential limiting force also acts by sliding by pressing in the radial direction and the axial direction with respect to the first and second receiving holes 43 and 45 of the ninth and eleventh.

  When the differential case 3 rotates in the other direction by the driving torque during coasting, the pair of helical side gears 5 and 7 receive a thrust force in the opposite direction (arrow B direction).

  For this reason, the left and right helical side gears 5 and 7 are pressed against each other with the inner facing surfaces 55 and 57 through the thrust bush 77.

During this coasting, the differential limiting force can be expanded with respect to the differential limiting force during driving for the following reasons.
[Increase of TBR by pinion gear arrangement]
FIG. 4 is a cross-sectional explanatory view showing the reaction force state of each part that works during driving, and FIG. 5 is an explanatory view of the relationship between the differential case and the pinion gear showing the reaction force state of each part that works during driving.

  At the time of driving, as shown in FIGS. 4 and 5, the side gear reaction force Fs against the helical side gears 5 and 7 acts on the gear portion 11b of the second helical pinion gear 11 (long), and the gear portion 11a In addition, a pinion gear (short) reaction force Fp acts on the first helical pinion gear 9 (short). By the reaction forces Fs and Fp, the second helical pinion gear 11 (long) is pressed against the second accommodation hole 45 in the radial direction.

  On the other hand, the side gear reaction force Fs acts on the first helical pinion gear 9 (short) in the gear portion 9b, and the pinion gear reaction force Fp acts on the gear portion 9a. This reaction force Fp is opposite to the reaction force Fs.

  Since the axial length L1 of the second helical pinion gear 11 (long) is longer than the axial length L2 of the first helical pinion gear 9 (short), a large so-called moment arm can be secured. Therefore, the sliding frictional force {gear reaction force between the first and second accommodation holes 43 and 45 of the differential case 3 and the tooth tip surfaces of the first and second helical pinion gears 9 and 11 that contribute to TBR. (F) × moment arm (L)} represents the second helical pinion gear 11 (long) and the first helical pinion gear 9 (short) from the relationship of the radial reaction force in FIG. In contrast, the arrangement of the differential case 3 on the rear side in the driving rotation direction becomes relatively large.

In this way, the coast side TBR can be increased more than the drive side simply by changing the arrangement of the first and second helical pinion gears 9, 11 (short) (long).
[Modification]
FIG. 6 is a chart showing the relationship between the front-rear arrangement of the first and second helical pinion gears and the TBR during driving and coasting. In the figure, S indicates the first helical pinion gear 9 (short), L indicates the second helical pinion gear 11 (long), and the forward rotation direction indicates the drive input rotation direction during driving.

  In the first comparative example, the first helical pinion gear 9 (short) is disposed on the rear side of the driving rotation direction of the differential case 3 during driving, and the pair of helical side gears 5 and 7 are opposed to each other during driving. The torsion angles of the first and second helical pinion gears 9 and 11 and the pair of helical side gears 5 and 7 were set so as to receive the thrust force toward the center.

  In this structure, the TBR was high during driving and low during coasting as in the prior art.

  In Comparative Example 2, the second helical pinion gear 11 (long) is disposed on the rear side of the driving rotation direction of the differential case 3 during driving, and the pair of helical side gears 5 and 7 are opposed to each other during driving. The torsion angles of the first and second helical pinion gears 9 and 11 and the pair of helical side gears 5 and 7 were set so as to receive the thrust force.

  In this structure, the TBR was high during driving and low during coasting as in the prior art.

  In Comparative Example 3, a plurality of pairs of the first and second helical pinion gears 9 and 11 are connected to the first helical gear that is short in the axial direction on the front side in the rotational direction when the differential case 3 rotates by receiving a driving input. A first pinion gear set 81 having a pinion gear 9 and a second helical pinion gear 11 that is axially long on the rear side in the rotational direction and a second helical pinion that is axially long on the front side in the rotational direction A second pinion gear set 83 in which the gear 11 is arranged and the first helical pinion gear 9 that is short in the axial direction on the rear side in the rotation direction is arranged, and two pairs are arranged alternately.

  Further, the first and second helical pinion gears 9 and 11 and the pair of helical side gears 5 are arranged so that the pair of helical side gears 5 and 7 receive a thrust force in the opposing direction during the drive. , 7 torsion angles were set.

  In this structure, the TBR was high during driving and low during coasting as in the prior art.

  In the first modification, a plurality of pairs of the first and second helical pinion gears 9 and 11 are provided with a first helical gear that is short in the axial direction on the front side in the rotational direction when the differential case 3 is rotated by receiving a driving input. A first pinion gear set 81 having a pinion gear 9 and a second helical pinion gear 11 that is axially long on the rear side in the rotational direction and a second helical pinion that is axially long on the front side in the rotational direction A second pinion gear set 83 in which the gear 11 is arranged and the first helical pinion gear 9 that is short in the axial direction on the rear side in the rotation direction is arranged, and two pairs are arranged alternately.

  Also, the first and second helical pinion gears 9 and 11 and the pair of helical side gears so that the pair of helical side gears 5 and 7 receive a thrust force in the opposite direction during the driving. A twist angle of 5 or 7 was set.

  In this structure, TBR was low during driving and high during coasting.

  In the second modification, the first helical pinion gear 11 (long) is disposed on the rear side in the driving rotation direction when the differential case 3 is driven, and the pair of helical side gears 5 and 7 are opposed to each other at the time of driving. The torsion angles of the first and second helical pinion gears 9 and 11 and the pair of helical side gears 5 and 7 were set so as to receive the thrust force.

  In this structure, TBR was low during driving and high during coasting.

As a result, Modification 1 and Modification 2 are obtained in addition to the first embodiment.
[Effect of Example 1]
The first embodiment of the present invention is a relatively short axial direction having a differential case 3 in which drive input is performed and an axis formed in the differential case 3 and parallel to the rotational axis of the differential case 3. First and second receiving holes 43 and 45, and the first and second receiving holes 43 and 45, which are rotatably held in the axial direction and mesh with each other on one side in the axial direction. The first and second helical pinion gears 9 and 11 are concentrically arranged in the differential case 3 so as to be rotatably opposed to each other, and the axial directions of the first and second helical pinion gears 9 and 11 And a pair of helical side gears 5 and 7 for engaging each other on the side to perform drive output, and the differential case 3 receives the drive input and rotates in front of the rotational direction during driving. A short first helical pinion gear 9 and a rear side in the rotational direction Placing the long second helical pinion gear 11 in the axial direction.

  For this reason, the torque bias ratio (TBR) during coasting can be increased more than during driving with a simple structure that simply changes the arrangement of the short and long helical pinion gears 9 and 11. it can.

Therefore, the output of the engine tends to be high power, and the demand for improving the stability with respect to full braking or the like during cornering can be easily satisfied with a simple structure.
[Others]
In relation to the present invention, other main features included in the above-described first embodiment will be described.

  In the conventional differential device, the torque / bias ratio of the differential device is set to a desired value so that drive characteristics on the drive side and coast side can be obtained according to the running characteristics of the vehicle. To set this desired value, as described above, it was accompanied by an increase in the optional washer and the addition of a friction member such as a friction clutch. For this reason, it is necessary to prepare various differential devices with different driving characteristics, and the differential devices may have different types of settings, so that one product can be set uniformly, resulting in trouble from design to manufacturing and management. .

  Therefore, as another main feature, as described in the first embodiment of the present application, a pair of helical members having a long and short axial direction in which the tooth tip surface is slidably held in the accommodation hole of the differential case. -Basic configuration requirements for a parallel-shaft differential device that exhibits differential limiting force, consisting of pinion gears and a pair of helical side gears that output meshing drive force to these helical pinion gears. And

  And the circumferential arrangement of the pair of helical pinion gears arranged in the rotation direction of the differential case and the opposite directions so as to mesh with the pair of helical pinion gears whose torsion angles are set in opposite directions to each other The torque bias ratio on the drive side and the coast side can be set in stages by combining the arrangement of a pair of helical side gears having a twist angle set to.

  The setting of the twist angle and the meshing state of each gear can be easily understood with reference to FIG.

  More specifically, referring to FIG. 6, first, three patterns of circumferential arrangements of long and short helical pinion gears are set on the front side and the rear side in the rotation direction of the differential case. Second, the pair of helical side gears that mesh with the pair of helical pinion gears are in contact with each other in the rotational direction of the drive side of the differential case that rotates by receiving the driving force, or separated from each other. Then, set the two patterns in the direction of contact with the differential case.

  In this way, in the parallel-axis differential device, the desired drive side and coast side drive characteristics can be set stepwise in accordance with the running characteristics of the vehicle.

  Adding to the design as an additional configuration can change the torsion angle of each gear in addition to the pattern setting described above, and this setting increases the setting range of the torque / bias / ratio. be able to.

  Thus, according to other main features, referring again to FIG. 6, a structure with a large drive-side torque / bias ratio is gradually formed in the order of Comparative Example 1 → Comparative Example 3 → Comparative Example 2. It is possible to set up three levels.

  On the other hand, a structure with a large torque side bias ratio on the coast side can be set in three stages, increased in the order of Modification 2 → Modification 1 → Embodiment 1.

  Therefore, the differential device can be set in six stages according to the running characteristics of the vehicle.

  Therefore, the basic configuration is specified and set in response to the torque / bias / ratio of the differential device according to the vehicle characteristics from the customer and corresponding to the desired torque / bias / ratio and the gear set pattern set in stages.

  And the design technique of setting the shape of the support periphery and connection part required for mounting and connection is constructed.

  Thereby, timely design according to the vehicle characteristics is possible, manufacturing becomes easy, and an excellent effect that complicated management of members and devices can be omitted can be exhibited.

It is the schematic perspective view which notched a part of differential apparatus. Example 1 It is a perspective view of the gear set which abbreviate | omitted the differential case. Example 1 It is sectional drawing of a differential apparatus. Example 1 It is explanatory drawing of the cross-sectional direction which shows the reaction force state of each part which acts at the time of a drive. Example 1 It is explanatory drawing of the relationship between the differential case and gear which show the reaction force state of each part which acts at the time of a drive. Example 1 It is a graph which shows the relationship between the front-back rotation direction arrangement | sequence of a 1st, 2nd helical pinion gear, and TBR at the time of a drive and a coast. Example 1

Explanation of symbols

1 differential device 3 differential case (case)
5,7 Helical side gear (helical output gear)
5a, 7a, 9a, 9b, 11a, 11b Gear part 9 First helical pinion gear 11 First helical pinion gear 43 First receiving hole 45 Second receiving hole

Claims (4)

A differential case where drive input is performed;
A relatively short axial first and second receiving hole formed in the differential case and having an axial core parallel to the rotational axis of the differential case;
First and second helical pinion gears that are relatively short in the axial direction and are held and held in the first and second receiving holes so as to be axially rotatable;
A pair of helical output gears that are concentrically and rotatably disposed in the differential case and are engaged with the first and second helical pinion gears to perform drive output,
The first helical pinion gear that is short in the axial direction is disposed on the front side in the rotational direction when the differential case is rotated by receiving the driving input, and the second helical pinion that is long in the axial direction on the rear side in the rotational direction.・ Gear is arranged,
A differential device characterized by that. The differential device according to claim 1,
A plurality of pairs of the first and second helical pinion gears are arranged on the outer periphery of the helical output gear.
A differential device characterized by that. A differential case where drive input is performed;
A relatively short axial first and second receiving hole formed in the differential case and having an axial core parallel to the rotational axis of the differential case;
A plurality of pairs of first and second helical pinion gears that are relatively short in the axial direction and are held and held in the first and second receiving holes so as to be axially rotatable;
A pair of helical output gears arranged to concentrically rotate and face each other in the differential case to engage with the first and second helical pinion gears and perform drive output;
In the plurality of pairs of the first and second helical pinion gears, the first helical pinion gear that is short in the axial direction is disposed on the front side in the rotational direction when the differential case is rotated by receiving a driving input. A first pinion gear set in which a second helical pinion gear that is long in the axial direction is arranged on the rear side in the rotation direction, and a second helical pinion gear that is long in the axial direction is arranged on the front side in the rotation direction and rotates. A second pinion gear set in which a first helical pinion gear that is short in the axial direction is arranged on the rear side in the direction,
The twist angles of the first and second helical pinion gears and the pair of helical output gears are set so that the pair of helical output gears receive a thrust force in the opposite direction during the driving,
A differential device characterized by that. A differential device according to claim 3, wherein
The first and second pinion gear sets are alternately arranged in two pairs on the outer periphery of the helical output gear.
A differential device characterized by that.

Images