JP2018013142A - Differential device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the collection performance of iron powder or magnet powder while suppressing a cost increase resulting from the securement of an excess space for a different part, and an increase of the number of part items.SOLUTION: A differential device liquid-tightly comprises a final reduction mechanism constituted of a drive pinion and a ring gear, a differential gear mechanism arranged in a differential case 41 which is arranged at an external peripheral part of the ring gear 45, and a lubricant in a housing 20. The differential device defines at least a part of a breather chamber 32 which is formed in an upper position of the differential case of the housing 20, and comprises a deflector plate 31 having a magnetic force being the deflector plate 31 for preventing the intrusion of the lubricant into the breather chamber 32.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a differential device, and more particularly to a vehicle differential device having a final reduction mechanism and a differential gear mechanism.

  In a differential device for a vehicle, generally, a final reduction mechanism and a differential gear mechanism are disposed in a housing (hereinafter also referred to as a differential housing) of the differential device, and ring gears constituting the final reduction mechanism are arranged. Lubricating oil stored in the housing is scraped up and scattered by utilizing rotation, and is supplied to a lubrication-required site to lubricate the site. In addition, the differential device is provided with a breather chamber that is covered and defined by a deflector plate so that the gas can flow in order to reduce the pressure change of the internal gas accompanying the change in the internal temperature of the differential housing. ing.

  In the differential device configured as described above, it is known that abrasion powder is generated by meshing rotation of each gear and rotation of each rotation shaft, and is mixed into lubricating oil. Such wear powder is generally iron powder or magnetic powder, and if left unattended, there is a risk of damaging the meshing portions of each gear and the bearing portion of each rotary shaft. Therefore, such wear powder is adsorbed and removed. Therefore, a technique using a drain plug with a magnet is disclosed (for example, see Patent Document 1).

JP 2008-51139 A

  However, in the technique disclosed in Patent Document 1 described above, since the diameter of the drain plug with magnet is limited, a magnet having a large adsorption surface area cannot be obtained, and as a result, the iron powder mixed in the lubricating oil In addition, there is a problem that it is difficult to efficiently adsorb and collect magnetic powder.

  In order to improve the recoverability of such iron powder or magnetic powder, it is conceivable to additionally provide a magnet in the differential housing, but in this case, a space for providing another magnet is required. There is a concern that the differential device itself may be increased in size and a cost increase due to an increase in the number of parts.

  The present invention has been made to solve the above-mentioned problems, and it is possible to recover iron powder or magnetic powder while suppressing an increase in cost due to securing an extra space for another part and increasing the number of parts. It is an object of the present invention to provide a differential device that can improve the performance.

One aspect of the present invention for solving the above problems is that a final reduction mechanism comprising a drive pinion and a ring gear is provided inside a housing, and a differential disposed within a differential case in which the ring gear is provided on the outer periphery. A differential device comprising a gear mechanism and lubricating oil in a liquid-tight manner,
A deflector plate that defines at least a part of a breather chamber formed at an upper position of the differential case in the housing and prevents entry of lubricating oil into the breather chamber, and has a magnetic force;
A differential apparatus comprising:

  According to the above aspect of the present invention, the lubricating oil scraped up by the rotation of the ring gear disposed on the outer periphery of the differential case defines at least a part of the breather chamber formed at the upper position of the differential case, It collides with or touches the deflector plate that prevents the lubricant from entering the breather chamber and flows down along the plate surface. At this time, most of the iron powder or magnetic powder mixed in the lubricating oil is adsorbed to the deflector plate having magnetic force. Here, the deflector plate itself is an existing component in the differential device, and most of the lubricating oil scraped up by the rotation of the ring gear collides with or comes into contact with the deflector plate, so that the deflector plate itself has a magnetic force. As a result, it is not necessary to secure a new space for another part, and while suppressing the increase in cost due to the increase in the number of parts, the efficient adsorption and recovery of iron powder or magnetic powder in the lubricating oil is improved. be able to.

It is a schematic explanatory drawing of a vehicle provided with the differential apparatus which concerns on this invention. It is a figure for demonstrating the differential apparatus by the 1st Embodiment of this invention, and is sectional drawing which follows the II-II line | wire of FIG. FIG. 3 is a partial cross-sectional side view of a differential carrier shown with a carrier cover and a differential gear mechanism of the differential device according to the first embodiment of the present invention shown in FIG. 2 removed. FIG. 3 is a partial cross-sectional side view of the differential carrier, with the carrier cover and the ring gear removed from the differential device according to the first embodiment of the present invention shown in FIG. 2. It is a front view which shows the deflector board in the differential apparatus by the 1st Embodiment of this invention. It is a partial section side view of a differential carrier for explaining a differential device by a 2nd embodiment of the present invention. It is a fragmentary sectional side view of the carrier cover for demonstrating the breather chamber of the differential apparatus by the 2nd Embodiment of this invention. Similarly, in order to explain the breather chamber of the differential device according to the second exemplary embodiment of the present invention, it is an inner view of the carrier cover as seen in the direction of the arrow in FIG. 7 with the deflector plate removed. It is an inner surface figure of the carrier cover for demonstrating the relationship between the deflector board and ring gear of the differential apparatus by the 2nd Embodiment of this invention.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. First, an embodiment in which a differential device according to the present invention is used as a differential device for driving front wheels and / or rear wheels in a four-wheel drive vehicle will be described.

  In the four-wheel drive vehicle AWD according to the present embodiment shown in FIG. 1, a longitudinal engine E, a transmission TM, a transfer TF provided with a switching mechanism CM for switching to two wheels or four wheels, a differential device FD for driving front wheels, A differential device RD for driving the rear wheels is provided. In the four-wheel drive state including the driving of the front wheels FW switched by the operation of the switching mechanism CM, the driving force from the engine E via the transmission TM is the transfer TF, the rear propeller shaft RP, the rear wheel drive. Is transmitted to the rear wheel RW via the differential unit RD for the vehicle, and is also transmitted to the front wheel FW via the differential unit FD for driving TF, the front propeller shaft FP, and the front wheel. In the two-wheel drive state, transmission of driving force from the transfer TF to the front wheel differential unit FD is blocked by the switching mechanism CM.

(First embodiment)
Hereinafter, a differential apparatus 10 according to a first embodiment of the present invention in which the present invention is applied to the above-described front-wheel drive differential apparatus FD will be described with reference to FIGS. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 1, that is, a cross section of the differential device 10 cut from a vertical plane including a rotation axis of a drive shaft described later and viewed from the rear. The differential device 10 includes a differential carrier (hereinafter also referred to as a differential carrier main body) 21 and a carrier cover 22, and is integrally formed by bolts 23 that are inserted and fastened through a plurality of holes formed in the flanges 21 a and 22 a. A housing 20 is provided.

  As will be described in detail below, a final reduction mechanism and a differential gear mechanism are disposed inside the housing 20 of the differential device 10. That is, as shown in FIGS. 3 and 4, the input shaft 26 is rotatably supported by the support portion 24 formed at one end portion of the differential carrier body 21 by a pair of rolling bearings 25 a and 25 b. One end portion of the input shaft 26 protrudes from the differential carrier main body 21, and a flange 26a connected to the above-described front propeller shaft FP is attached to the one end portion. In addition, a ring gear 45 (not shown in FIGS. 3 and 4) attached to a differential gear case (hereinafter referred to as a differential case) 41 of a differential gear mechanism 40 described later is provided at the other end of the input shaft 26. A drive pinion 27 that meshes with each other so as to transmit torque. Thus, the drive pinion 27 and the ring gear 45 constitute a final reduction mechanism. The rotational driving force transmitted to the input shaft 26 is transmitted to the front wheels FW via the left and right drive shafts 53a and 53b, which will be described later, via the final reduction mechanism and the differential gear mechanism 40 provided in the housing 20. .

  Here, the differential gear mechanism 40 will be briefly described with reference to FIG. 2 again. The differential gear mechanism 40 includes the above-described differential case 41, a pair of side gears 42a and 42b disposed in the differential case 41 facing left and right, and pinion gears 44a and 44b (see FIG. 2) that mesh with the side gears 42a and 42b, respectively. Only one pinion gear 44a is shown), and includes a pinion shaft 43 that rotatably supports these pinion gears 44a and 44b, and the differential case 41 has a differential carrier body 21 and a carrier cover at the left and right ends. 22 are rotatably supported by a pair of rolling bearings 51a and 51b.

  A ring gear 45 of a bevel gear is fastened to the outer peripheral portion of the differential case 41 by a bolt 46. As described above, the ring gear 45 meshes with the drive pinion 27 to constitute a final reduction mechanism.

  The differential case 41 is formed with cylindrical portions 52a and 52b coaxially with the inner ring fitting surfaces of the rolling bearings 51a and 51b. The cylindrical portions 52a and 52b receive the left and right drive shafts 53a and 53b and rotate. I support it as possible. A spline extending in the axial direction is formed at the tip of the drive shafts 53a and 53b, and is configured to engage with the splines formed on the inner periphery of the side gears 42a and 42b so as to transmit torque. Oil seals 54a and 54b are provided between the outer peripheral surface of the left drive shaft 53a and the inner peripheral surface of the differential carrier body 21, and between the outer peripheral surface of the right drive shaft 53b and the inner peripheral surface of the carrier cover 22. It is provided, and the rotating shaft is liquid-tightly sealed to prevent the lubricating oil stored in the housing 20 from flowing out. In the embodiment shown in FIG. 2, the left drive shaft 53a is formed integrally with the outer ring of the constant velocity joint 53c, and further connected to the intermediate shaft 53d. The right drive shaft 53b is the same, although not shown.

  In the first embodiment, a drain plug 33 is screwed through the wall facing the tooth surface of the ring gear 45 at the lower part of the differential carrier body 21, and the drain plug 33 is attached to the tip of the drain plug 33. A magnet 33a is attached as necessary (see FIG. 2). Further, a breather port 28 for circulating gas is provided at the upper part of the differential carrier main body 21 to relieve the pressure change when the air inside the housing 20 expands and contracts with the temperature change of the differential device 10. A breather plug 29 is attached to the breather port 28 (see FIG. 2).

  On the inner wall surface of the differential carrier main body 21 in the vicinity of the breather port 28, a protrusion that protrudes toward the tooth surface direction of the ring gear 45 so as to surround the lower vicinity region of the breather port 28 and define a breather chamber 32. A wall 30 is formed. The deflector plate covers the entire surface of the open end surface opened in the tooth surface direction of the ring gear 45 of the breather chamber 32 surrounded by the projecting wall portion 30 so as to define at least a part of the breather chamber 32. 31 is attached by screws 31a and 31a (see FIG. 5).

  On the other hand, a part of the projecting wall portion 30 below the breather chamber 32 is formed with a notch 30a that serves as an air passage when the deflector plate 31 is attached. When inflated or deflated, air is discharged and sucked through the notch 30a and the breather chamber 32. As a result, the deflector plate 31 directly receives and blocks the lubricating oil that the ring gear 45 positioned facing the breather chamber 32 scrapes, and the lubricating oil is supplied to the breather chamber 32 defined behind the deflector plate 31. Prevent direct intrusion.

  In this embodiment, the deflector plate 31 is formed so as to have a magnetic force from a magnetic material that is entirely magnetized. However, other various embodiments are possible, for example, a magnet is affixed to a substrate such as a synthetic resin, or an adhesive layer in which magnetic powder with magnetic force is mixed is applied to a substrate of iron material or aluminum material By doing so, the deflector plate may be formed to have a magnetic force.

  In the differential device 10 of the first embodiment configured as described above, when the rotational driving force of the engine is transmitted to the input shaft 26 via the transfer TF and the front propeller shaft FP, the drive pinion at the tip of the input shaft 26 27 is rotationally driven in the housing 20, and a ring gear 45 meshing with the drive pinion 27 and a differential case 41 bolted to the ring gear are rotated.

  When the resistance received by the left and right wheels from the road surface is substantially the same as when the vehicle is traveling straight ahead, the rotational resistances of the left and right side gears 42a and 42b are substantially the same, and the pinion gears 44a and 44b mesh with the side gears 42a and 42b. Does not generate a rotational force around the pinion shaft 43. For this reason, the left and right drive shafts 53 a and 53 b are driven to rotate at the same rotational speed together with the differential case 41 without rotating relative to the differential case 41.

  On the other hand, when the resistance of the left and right wheels received from the road surface is different, for example, when the vehicle is turning, for example, when the resistance of the left wheel in FIG. 2 is large, the rotational resistance of the left side gear 42a in the differential case 41 Is larger than the rotational resistance of the right side gear 42b, and a rotational force is generated around the pinion shaft 43 in the pinion gears 44a and 44b meshing with the side gears 42a and 42b in accordance with the rotational resistance. For this reason, a rotational speed difference occurs between the left and right drive shafts 53a and 53b. For example, in the above example, the left drive shaft 53a is slower than the rotational speed of the differential case 41, and the right drive shaft 53b is faster than the rotational speed of the differential case 41. Driven by rotation.

  Therefore, when the left and right wheels receive different resistances from the road surface as described above, the side gears 42a and 42b and the pinion gears 44a and 44b are rotated in the differential case 41 to support the pinion shaft 43 and the drive shaft. Relative rotation occurs between the cylindrical portions 52a and 52b of the differential case 41 that supports 53a and 53b. For this reason, the inside of the differential gear mechanism 40 is also lubricated.

  Therefore, the lubricating oil is stored in the housing 20 of the differential device 10 of the first embodiment, and the final reduction mechanism, the differential gear mechanism, the bearing, and the like are lubricated by the lubricating oil scooped up by the rotational force of the ring gear 45. Lubrication is performed. Various types of lubricating means are provided in the housing 20 in order to efficiently guide the lubricating oil scraped up by the ring gear 45 to each lubricated portion.

  According to the first embodiment of the present invention, the lubricating oil stored in the housing 20 is scraped up by the rotation of the ring gear 45 disposed on the outer peripheral portion of the differential case 41 and is positioned above the differential case 41. It collides with or comes into contact with the deflector plate 31 having a high magnetic force, and flows down along the plate surface having a relatively large surface area. At this time, most of the iron powder or magnetic powder mixed in the lubricating oil is easily adsorbed because the contact time with the deflector plate 31 having a relatively large surface area is long. On the other hand, the iron powder or the magnetic powder mixed in the lubricating oil flowing down from the deflector plate 31 and / or the lubricating oil that is positioned below the ring gear 45 and stirred is also applied to the magnet 33a of the drain plug 33 with magnet. Adsorbed. Thus, efficient adsorption and recovery of iron powder or magnetic powder in the lubricating oil are improved.

(Second Embodiment)
Next, as a second embodiment of the present invention, a differential device 110 in which the present invention is applied to the above-described differential device RD for driving rear wheels will be described with reference to FIGS. In addition, about the same member or the same functional member as described in the first embodiment, the same reference numerals are used in the last two digits excluding the hundreds to avoid redundant description and only different portions will be described. To.

  The differential device 110 for driving the rear wheel includes a differential carrier main body 121 and a carrier cover 122, and is integrally formed by bolts 123 that are inserted and fastened through a plurality of holes formed in the flanges 121a and 122a. The housing 120 is provided.

  A final reduction mechanism and a differential gear mechanism are disposed inside the housing 120 of the differential device 110, and a pair of support portions 124 formed at one end of the differential carrier body 121 are provided with a pair as shown in FIG. The input shaft 126 is rotatably supported by the rolling bearings 125a and 125b. One end of the input shaft 126 protrudes from the differential carrier body 121, and a flange 126a connected to the above-described rear propeller shaft RP is attached to the one end. Further, a drive pinion 127 that meshes with a ring gear 145 assembled to the differential case 141 of the differential gear mechanism 140 so as to transmit torque is provided at the other end of the input shaft 126. Thus, the drive pinion 127 and the ring gear 145 constitute a final reduction mechanism. The rotational driving force transmitted to the input shaft 126 is transmitted to the rear via left and right drive shafts (not shown in FIG. 6) via a final reduction mechanism and a differential gear mechanism 140 provided in the housing 120. It is transmitted to the wheel RW.

  In the second embodiment, a drain plug 133 is screwed through the wall surface parallel to the axis of the ring gear 145 at the lower part of the differential carrier main body 121, and is necessary at the tip of the drain plug 133. Accordingly, a magnet 133a is mounted (see FIG. 6). Further, in the second embodiment, a breather port 128 through which a gas is circulated is provided on the carrier cover 122 in order to relieve a change in air pressure inside the housing 120 due to a temperature change of the differential device 110. The breather plug 129 is attached to the breather port 128 (see FIGS. 6 and 7).

  A direction parallel to the tooth surface (rotation plane) of the ring gear 145 so that the inner wall surface of the carrier cover 122 in the vicinity of the breather port 128 surrounds the lower vicinity region of the breather port 128 and defines the breather chamber 132. A projecting wall portion 130 is formed to project. The opening end surface of the breather chamber 132 surrounded by the projecting wall 130 opens in a direction parallel to the plane of rotation of the ring gear 145 so as to define at least part of the breather chamber 132. The deflector plate 131 is attached by screws 131a (see FIGS. 7 and 9).

  On the other hand, a part of the projecting wall portion 130 below the breather chamber 132 is formed with a notch portion 130a that serves as an air passage when the deflector plate 131 is attached. When inflated or deflated, air is discharged and sucked through the notch 130a and the breather chamber 132. As a result, the deflector plate 131 directly receives and blocks the lubricating oil scraped up in the main scattering direction (shown by the white arrow in FIG. 9) by the ring gear 145 positioned in parallel with the breather chamber 132. The direct entry of the lubricating oil into the breather chamber 132 defined behind the deflector plate 131 is prevented.

  Also in the second embodiment, the deflector plate 31 may be formed in various forms as described in the previous embodiment.

  In the differential device 110 of the second embodiment configured as described above, when the rotational driving force of the engine is transmitted to the input shaft 126 via the transfer TF and the rear propeller shaft RP, the drive at the tip of the input shaft 126 is driven. The pinion 127 is rotationally driven in the housing 120, and the ring gear 145 that meshes with the drive pinion 127 and the differential case 141 that is bolted to the ring gear are rotated.

  Thus, according to the second embodiment of the present invention, the lubricating oil stored in the housing 120 is scraped up by the rotation of the ring gear 145 disposed on the outer peripheral portion of the differential case 141, and the carrier cover 122 It collides with or comes into contact with the deflector plate 131 having the magnetic force located at the upper part, and flows down along the plate surface having a relatively large surface area. At this time, most of the iron powder or magnetic powder mixed in the lubricating oil is easily adsorbed since the contact time with the deflector plate 131 having a relatively large surface area is long. On the other hand, the lubricating oil flowing down from the deflector plate 131 and / or the iron powder or the magnetic powder mixed in the lubricating oil that is located below the ring gear 145 and stirred is also applied to the magnet 133a of the drain plug 133 with magnet. Adsorbed. Thus, the adsorption and recovery of iron powder or magnetic powder in the lubricating oil is efficiently performed.

  In the first and second embodiments described above, the differential apparatus according to the present invention is a differential for front wheels and rear wheels of a four-wheel drive vehicle based on a front engine / rear drive vehicle (FR vehicle). Although the example applied to each of the devices has been described, the present invention is not limited to such a type of vehicle, and any type of vehicle may be used as long as it is a differential device including a reduction mechanism and a differential gear mechanism in a housing. It can be applied even if it exists. For example, the present invention can be applied to a differential device for a rear wheel of a front engine / rear drive vehicle (FR vehicle) and a differential device for a front wheel of a front engine / front drive vehicle (FF vehicle).

  As mentioned above, although the form for implementing this invention was demonstrated, this invention is not limited to such embodiment at all, and it can implement with a various form in the range which does not deviate from the summary of this invention. Of course.

10,110 Differential device 20,120 Housing 21, 121 Differential carrier (Differential carrier)
22, 122 Carrier cover 31, 131 Deflector plate 32, 132 Breather chamber 33, 133 Drain plug 40, 140 Differential gear mechanism 41, 141 Differential gear case (Differential case)

Claims (1)

Liquid-tightening a final reduction mechanism composed of a drive pinion and a ring gear, a differential gear mechanism disposed inside a differential case in which the ring gear is disposed on the outer periphery, and lubricating oil inside the housing A differential device comprising:
A deflector plate that defines at least a part of a breather chamber formed at an upper position of the differential case in the housing and prevents entry of lubricating oil into the breather chamber, and has a magnetic force;
A differential apparatus comprising:

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