JP2551600B2 - Lubricating oil amount measuring device for transfer gear in power transmission device for four-wheel drive vehicle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a power transmission device for a four-wheel drive vehicle, particularly a four-wheel drive based on a front engine / front wheel drive (hereinafter referred to as FF) for horizontal mounting. The present invention relates to a lubricating oil amount measuring device in a transfer gear part of a power transmission device for a vehicle, and more specifically, in a sealed chamber in a transfer gear part that houses a transfer drive gear that transfers power from an engine to a rear wheel and a transfer driven gear that meshes with the transfer drive gear. The present invention relates to a lubricating oil amount measuring device for a transfer gear unit, which is used to measure the level of enclosed lubricating oil using an oil level gauge.

(B) Conventional technology In general, a power transmission device for a four-wheel drive vehicle based on F / F is a transfer for transmitting power from an engine to rear wheels in both a part-time system and a full-time system. A gear unit is installed, and a hypoid gear is used for the gear unit. Therefore, lubricating oil containing an extreme pressure additive is used as a lubricant in the gear portion, and the gear portion is separated from other portions in which the same lubricating oil is used as in the automatic transmission, etc. It is stored in.

The gear or the bearing of the pinion shaft housed in the sealed chamber is immersed in the lubricating oil containing the extreme pressure additive sealed in the sealed chamber and lubricated by the so-called oil bath lubrication method. Lubricating oil is forcibly supplied to the meshing portion of the gear and the rotating portion of the bearing by a lubricating oil foundation such as an oil pump arranged in the closed chamber, so that lubrication is efficiently performed.

(C) Problems to be solved by the invention By the way, if a large amount of lubricating oil is enclosed in the above-mentioned closed chamber, lubrication of each part is surely performed, but due to the posture and swing of the vehicle during traveling, or the gear Due to the splashing action due to rotation, the expensive lubricating oil containing the extreme pressure additive blows out from the breather hole in the upper part of the sealed chamber and is wasted. Conversely, if the amount of lubricating oil enclosed is too small, poor lubrication occurs. It is necessary to enclose a proper amount of lubricating oil in the closed chamber. Therefore, conventionally, an opening that communicates with the internal closed chamber is formed in the upper part of the transfer case, and the oil level gauge is configured to be inserted from outside the opening, depending on the degree of twist of the inserted oil level gauge, It was timely confirmed whether or not an appropriate amount of lubricating oil was enclosed in the closed chamber, but the closed chamber was extremely narrow due to the structure in which transfer drive gears, etc. were uniformly housed,
Therefore, the inserted oil level gauge hits the transfer drive gear or other parts on the way and does not reach the predetermined part of the bottom of the sealed chamber, and the oil level gauge must be inserted again many times, and the lubricating oil level can be measured. However, there is an inconvenience in that a great deal of labor and skill are required in order to do so. Further, due to the existence of the opening, there is a drawback that the splashed lubricating oil is blown out from the opening when the power transmission device is operated.

Therefore, in the present invention, a guide member is disposed below the opening formed in the transfer case to properly guide the inserted oil level gauge to a predetermined portion of the bottom of the closed chamber, thereby eliminating the above-mentioned problems. An object of the present invention is to provide a lubricating oil amount measuring device for a transfer gear portion in a power transmission device for a four-wheel drive vehicle as described above.

(D) Means for Solving the Problems The present invention has been made in view of the above circumstances, and, for example, as shown with reference to FIGS. 1 to 3, a transfer drive is provided in a sealed chamber (D) formed inside. In a power transmission device (U) for a four-wheel drive vehicle, which has an opening (13e) for inserting an oil level gauge (60) formed in an upper portion of a transfer case (13) accommodating a gear (17) and the like, the opening ( 13
e) A first guide part (59a) for correcting lateral deflection of the oil level gauge (60) inserted through the opening (13e) in the lower closed chamber (D), and the first guide part (59a). Guide part (5
9a) is located on the side adjacent to the gear (17) side, corrects the deflection of the oil level gauge (60) toward the gear (17) side, and the opening (13e) for the lubricating oil during operation It is characterized in that a guide member (59) having a second guide portion (59b) for preventing splashing is provided.

(E) Operation Based on the above configuration, when measuring the level of the lubricating oil sealed in the closed chamber (D), for example, the guide pipe (57) arranged laterally of the power transmission device (U) at the lower part of the vehicle is used. From the end, a long rod-shaped oil level gauge (60) made of a flexible material such as spring steel is inserted. Then, the gate (60)
Is guided along the inner surface of the guide tube (57) and introduced into the sealed chamber (D) through the opening (13e) of the transfer case (13), and the first guide portion (59a) of the guide member (59). ) Is used to prevent lateral deflection and the second guide portion (59b) is guided while preventing deflection to the transfer drive gear (17) side, so that smooth movement can be achieved without colliding with the gear (17) or the like. Is guided toward a predetermined site on the bottom of the closed chamber (D). Also, power transmission device (U)
Even if the lubricating oil is splashed by the rotation of the transfer drive gear (17) during the operation of the guide member (5
The second guide part (59b) of 9) shields the lubricating oil splashed from the opening (13e) to the outside.

(F) Example Hereinafter, an example of the present invention will be described with reference to the drawings.

As shown in FIG. 4, a power transmission device U for a full-time front engine front four-wheel drive vehicle of a full-time type has an input gear 1 to which power is transmitted from an engine (not shown) via a torque converter and an automatic transmission. The input gear 1 is fixed to the gear mount case 2. The mount case 2 is composed of divided case pieces, is fastened together with the input gear 1 by bolts 12, and is supported by the support case 9 by tapered roller bearings 9a, 9 and inside thereof, the front differential device 3 and A differential control device 10 is housed. Further, the front differential device 3 has a front differential case 3c rotatably supported by two needle bearings 11a and 11b in the mount case 2, and the differential case 3c is provided.
Is a carrier configured by vertically supporting a plurality of pinion shafts 3d that support the pinion 3p, and also the left and right side gears.
3a, 3b extend in the left-right direction and are rotatably supported.
The left and right front axles 8l, 8r are respectively connected to the side gears 3a, 3b so as to be able to transmit power.

Also, on the right side of the input gear mount case 2, that is,
A transfer case 13, which is composed of left and right split pieces 13a and 13b, is attached to the rear of the engine. The transfer case 13 is coaxial with the input gear mount case 2 and the front differential device 3 in the transfer case 13. 15 are assembled. The transfer gear portion 15 has a ring gear mount case 16, the ring gear mount case 16 can be divided into two parts, left and right, and integrally supports a transfer drive gear 17 for driving rear wheels, which is a hypoid gear. With
The transfer case (13) is rotatably supported by a pair of tapered roller bearings (19, 19). A transfer drive gear 21, which is a hypoid gear formed on the pinion shaft 20, is constantly meshed with the gear 17, and the pinion shaft 20 is extended to the rear by an extension case 24 and a tapered roller bearing.
It is rotatably supported via 24a, 24b, transmitted to the universal joint 25 via the spline portion 20a, and capable of transmitting power to the left and right rear axle shafts via a propeller shaft and a rear differential device (not shown). It is connected. On the other hand, a center differential device 18 is disposed in the ring gear mount case 16, and the center differential device 18 includes a differential carrier 18c having an open end. Further, the diff carrier 18c is connected to the sleeve portion 2b extending from the input gear mount case 2, and the opposite side of the connecting boss portion 18c 'is open to form an open end, and the open end portion and Connection boss 18
The ring gear mount case 16 is rotatably supported by the ring gear mount case 16 with needle bearings 23 and 23 interposed therebetween. Further, the differential gear 18c has a pinion shaft supporting the pinion 18p.
18d is attached, the right side gear 18b is directly splined to the ring gear mount case 16,
Also, the left side gear 18a is attached to the Tefky carrier connecting boss 1
Linked to the differential case 3c of the front differential 3 through 8c 'in a fitting inserted and sleeve portion 3c which is fitted on the right front axle shafts 8r _1'.

The differential control device 10 is disposed in the input gear mount case 2 provided so as to cover the front differential device 3 and coaxially with the device 3. The differential control device 10 includes a wet friction multi-plate clutch 26 and a hydraulic actuator thereof. Consists of 27. The clutch 26 has its outer friction plate connected to the mount case 2 and its inner friction plate connected to the differential case 3c, and these friction plates are pressed and controlled by the hydraulic actuator 27. Further, the hydraulic actuator 27 is arranged in an oil-tight manner between the first piston 28 and the second piston 29, which are housed in a cylinder formed in the mount case 2 in an oil-tight manner, and between both pistons. Reaction plate 30
These pistons constitute a double piston with the first piston 28 abutting on the outer peripheral flange of the second piston 29 and the reaction force plate 30 abutting on the cylinder end face.
The transfer case 13 is provided with a valve unit 31 for the differential control device 10. The control oil pressure from the unit 31 is supplied to the first piston 28 of the hydraulic actuator 27 through a pipe 32 and oil passages 33 and 35. And the second piston 29.

A lubricating oil supply hole 39 is formed in the support case 9, and the lubricating oil supplied from the supply hole 39 is the sleeve portion 2b.
Needle bearings 11a, 23, 2 through holes 40 formed in
The lubricating oil that lubricates 3 and the like and is discharged from the discharge hole 41 formed in the case 13 and guided to the front differential device 3 direction through the needle bearing 11a passes through the clearance a into the mount case 2. The oil accumulates, lubricates the friction plate of the clutch 26, and is discharged from the discharge hole 42 formed in the mount case 2. Furthermore, the sleeve part 3
From the hole 43 formed in c ₁ ′, the axle shaft 8r and the sleeve portion 3c
_The lubricating oil guided to b between 1'and 3'is supplied to the front differential case 3c3c through the thrust washer.
After the lubricating oil that collects in the chamber C formed inside and overflows lubricates the thrust washer between the mount case 2 and the differential case 3c, part of it is needle bearing
Lubricate 11b.

Oil seals 50, 51 are provided at both end portions of the gear mount case 16, that is, outside the tapered roller bearings 19, 19, so that these oil seals 5 are provided.
1,51, gear mount case 16, transfer case 1
3, an extension case 24 and a sealed chamber D defined by the oil seal 54 at the tip of the case are formed. A pump drive gear 52 is fixedly provided on the outer peripheral surface of the gear mount case 16, and an oil pump 53 and an eccentric rotor of the pump are provided in the chamber D between the extension case 24 and the transfer case 13. A gear 55 that drives the gear and meshes with the gear 52 is provided. Further, a strainer 56 is disposed adjacent to the oil pump 53, and the lubricating oil containing the extreme pressure additive enclosed in the closed chamber D is sucked from the strainer 56, and each component in the closed chamber D is sucked. Is lubricated by a system different from the above-mentioned lubrication system.

On the other hand, in the upper rear part of the transfer case 13,
As shown in FIGS. 1 to 3, for example, by utilizing the mating surfaces 13c and 13d of the left and right divided pieces 13a and 13b that form the case 13,
By combining the left and right divided pieces 13a and 13b, an opening portion 13e that vertically communicates with the inside of the closed chamber D is formed, and the left and right divided pieces 13a and 13b are formed in the opening portion 13e. When they are aligned, the end portion of the guide tube 57 guided from the left side (see FIG. 3) of the power transmission device U arranged at the lower part of the vehicle is firmly clamped and fixed. . Then, a guide member 59 is fixedly provided to the right divided piece 13b, for example, on the right side divided piece 13b by a fixing means, and is located below the opening 13e. The guide portion 59a corrects the deflection of the oil level gauge 60, which is inserted by being deflected rightward as viewed in FIG. 3 via the guide tube 57, and at the same time, the first guide portion 59a of the first guide portion 59a is corrected. It is deflected toward the gear 17 side through the guide tube 57 by a wide plate-shaped second guide portion 59b which rises from the side end and is adjacent to the transfer drive gear 17 side and curved along the outer periphery of the gear. The deflection of the oil level gauge 60 that has been inserted is corrected, and the lubricating oil splashed by the transfer drive gear 17 is not directly applied to the opening 13e during operation. Further, the third guide part 59c is formed on the side opposite to the second guide part 59b of the first guide part 59a so as to rise, and the transfer of the oil level gauge 60 inserted by the third guide part 59c is formed. The deflection toward the inner wall surface of the case 13 is corrected. Further, below the guide member 59, a guide body 61 composed of a pair of guide pieces 61a and 61b fixed to the left and right divided pieces 13a and 13b, for example, is provided.
1, the first and third guide portions 59a and 59c of the guide member 59 are
Thus, the oil level gauge 60 whose deflection has been corrected in the front-rear direction of the transfer case 13 can be positioned more reliably in the left-right direction of the transfer case 13. When the oil level gauge 60 can be guided downward in the substantially vertical direction of the closed chamber D only by the first and second guide portions 59a and 59b of the guide member 59, the third guide portion 59c and the guide The body 61 can be omitted.

 Next, the operation based on the above structure will be described.

The rotation of the engine is appropriately shifted by the automatic transmission and transmitted to the input gear mount case 2 via the input gear 1. During normal driving, the valve unit
31 is in a connected state, and the line pressure is the pipe 32 and the oil passage 3
Both pistons 28,29 of the hydraulic actuator 27 via 3,35
The wet multi-plate clutch 26 is in the connected state at a predetermined pressure. Therefore, in the center differential device 18, the differential carrier 18c and the left side gear 18a are coupled with each other with a predetermined coupling force, and the differential is limited by the predetermined regulation force. Accordingly, when the frictional force between the road surface and the tire is smaller than the above-mentioned regulation force, for example, on a road surface having a small friction coefficient such as a snow road or a dirt road, the center differential device 18 is directly connected based on the pressure force of the clutch 26. In a close state, the rotation of the input gear mount case 2 is transmitted to the differential case 3c of the front differential device 3 through the friction clutch 26 and the center differential device 18 that rotates integrally, and is further transmitted through the pinion 3p to the left and right side gears 3a, The torque is distributed to 3b to drive the left and right front wheels, and the torque is distributed to the pinion shaft 20 via the ring gear 17 and the gear 21 fixed to the center differential device 18, and the rear differential device distributes the torque to the left and right rear wheels. To drive. Further, when the frictional force between the road surface and the tire is substantially balanced with the regulating force by the clutch 26, for example, when traveling on a paved road at a relatively high speed, the tire slip is reduced in relation to the road surface friction coefficient. The clutch 26 is pressed while sliding so as not to occur. That is, the center differential device 18 distributes the torque to the front and rear wheels while absorbing the difference in rotation between the front and rear wheels in a state in which the torque is distributed to the front wheels so that the torque distribution to the front wheels approaches 50:50.

Further, when the steering angle is turned to a large extent at a low speed, such as when entering a garage, a difference in rotation occurs between the front wheels and the rear wheels. The engaging force of the friction clutch 26 of the differential control device 10 is also weak. Therefore, the center differential device 18 based on the rotation difference between the front wheels and the rear wheels is used.
In order to allow the relative rotation of the left and right side gears 18a and 18b, the friction clutch 26 slips to allow the differential of the center differential device 2 to transmit the torque to the front and rear wheels while preventing the occurrence of the tight corner braking phenomenon. To do.

Also, based on the rotation of the gear mount case 16, the gear 5
The oil pump 53 is driven through 2,55, the lubricating oil in the closed chamber D is sucked in through the strainer 56, and is appropriately discharged to the outside of the bearing 24b through the oil passage.
It is discharged toward the meshing portion of the transfer drive and the driven gears 17 and 21. The lubricating oil discharged near the bearing 24b lubricates the bearing 24b, lubricates the sliding spline 20a between the drive gear 20 and the universal joint 25, and lubricates the bearing 24a when returning to the pump direction.

On the other hand, when measuring the level of the lubricating oil in the closed chamber D, the oil level gauge 60 is inserted from the end of the guide tube 57. Then, the long bar-shaped gauge 60 made of a flexible body is used.
Is guided along the inner surface of the guide tube 57 and introduced into the sealed chamber D through the opening 13e formed in the upper portion of the transfer case 13, and as shown in FIG.
The right guide portion 59a prevents the deflection to the right, and as shown in FIG. 1, the second guide portion 59b of the guide member 59 prevents the deflection toward the transfer drive gear 17 side and sequentially seals. It is introduced to the lower side of D and reaches a predetermined position on the bottom of the sealed chamber D without colliding with the gear 17 or the like in the introduction process. When the power transmission device U operates, the transfer drive gear 17
The lubricating oil is splashed up by the rotating member inside the uniform closed chamber D, but the lubricating oil splashed up toward the opening 13e is returned to the closed chamber D by the shielding action of the second guide portion 59b of the guide member 59, Lubricant oil is prevented from blowing out from the opening 13e.

In the above-described embodiment, the differential control device 10 is used in the differential state at all times, but it may be used as a so-called diff lock mechanism that is normally inactive and operates only when necessary. Is. Further, the full-time four-wheel drive device having the center differential device has been described, but the present invention is also applicable to a part-time four-wheel drive device in which a clutch is interposed in the power transmission system at the rear wheels.
It can also be applied to a four-wheel drive device having a viscous coupling.

(G) Effect of the Invention As described above, according to the present invention, the transfer chamber (13) is provided in the closed chamber (D) below the opening (13e) for inserting the oil level gauge (60). A first guide portion (59a) for correcting lateral deflection of the oil level gauge (60) inserted through the opening portion (13e), and a transfer drive gear of the first guide portion (59a). It is located on the side adjacent to the (17) side, corrects the deflection of the oil level gauge (60) toward the gear (17) side, and prevents the lubricating oil from splashing the opening (13e) during operation. Since the guide member (59) having the second guide portion (59b) for preventing is arranged, the oil level gauge (60) can be used by any skill when measuring the lubricating oil level in the seal (D). Very easily and accurately without the need for a closed chamber (D) bottom It is possible to reach a predetermined part, the measurement is quick, and the second guide part (59b) is used to prevent the lubricating oil from blowing out from the opening (13e) without providing any special device. To treat
The configuration of the device is extremely simple and inexpensive.

[Brief description of drawings]

FIG. 1 is a view showing a main part of a lubricating oil amount measuring device according to the present invention, and is a view taken along the arrow I-I in FIG. 4, and FIG.
FIG. 3 is a sectional view showing a front view of a power transmission device for a four-wheel drive vehicle to which the present invention is applied, and FIG. 13 …… Transfer case, 13e …… Opening, 15 ……
Transfer gear part, 17 ... Transfer drive gear, 59 ... Guide member, 59a ... First guide part, 59
…… Second guide part, 60 …… Oil level gauge, D…
… Sealed chamber, U… Power transmission device for four-wheel drive vehicle.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Fumitomo Yokoyama 10 Takane, Fujii-cho, Anjo-shi, Aichi Aisin Warner Co., Ltd. (72) Inventor Masaharu Tanaka 1-cho, Toyota-cho, Aichi Prefecture Toyota Motor Corporation In-house (72) Inventor Kojiro Kuramochi 1 Toyota-cho, Toyota-shi, Aichi Toyota Motor Co., Ltd.

Claims (1)

(57) [Claims] 1. A power transmission device for a four-wheel drive vehicle in which an opening for inserting an oil level gauge is provided in an upper portion of a transfer case in which a transfer drive gear and the like are housed in a hermetically sealed chamber formed inside. A first guide part for correcting lateral deflection of the oil level gauge inserted from the opening in the closed chamber, and a side of the first guide part adjacent to the gear side, and the oil A guide member having a second guide portion for correcting the deflection of the level gauge toward the gear side and preventing splashing of the lubricating oil to the opening portion during operation is provided. Lubricating oil amount measuring device for transfer gear in power transmission device for four-wheel drive vehicle.