JPH0729354U - Lubrication structure of extension housing - Google Patents

Abstract

(57) [Summary] [Purpose] Lubrication is performed even when the distance between the oil reservoir of the mission case and the extension housing is long, and when the output shaft from the mission case is not rotating or is rotating in the reverse direction. (EN) Provided is a lubrication structure which can always secure the required amount of oil and can avoid layout problems. [Structure] In a spline fitting portion B between an output shaft 4 and a sleeve yoke 5 in an extension housing 3 which is made a closed space by sealing means 12 and 14, a space volume in the housing 3 is caused by relative movement of both in an axial direction. Is provided with a volume varying means 16 for changing the above, and the communication portion 7x on one side for communicating the inside of the mission case 1 and the inside of the housing 3 with each other.
Is provided with a first one-way valve 9 that allows a fluid flow into the housing 3, and a second one-way valve 10 that allows a fluid flow into the mission case 1 is provided at the communication portion 8x on the other side. To arrange.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a lubrication structure for an extension housing, and more particularly, to an improvement in a lubrication structure for lubricating the inside of an extension housing by utilizing lubricating oil in a mission case.

[0002]

[Prior art]

 Generally, an extension housing is installed on the output end side of the mission case for the purpose of holding a sleeve yoke connected to the base end of the propeller shaft.

It is usual that the opposite ends of the sleeve yoke and the output shaft of the transmission are connected by spline fitting so as to be relatively movable in the axial direction and not relatively rotatable.

The bearing portion of the output shaft and the spline fitting portion between the output shaft and the sleeve yoke need to be lubricated to prevent wear and seizure. Examples include an oil guide type and a screw pump type.

As shown in FIG. 4, the outline of the oil guide type lubrication structure includes a passage forming member 22 such as a gutter having one end located inside the mission case 20 and the other end located inside the extension housing 21. The partition walls 23 of both are penetrated and arranged in an inclined shape. According to this, the lubricating oil in the oil sump 20A at the bottom of the mission case 20 is splashed up by the gear 24 and the like, then flows down through the passage forming member 22 and falls into the extension housing 21. The lubricating oil lubricates the bearing 26 of the output shaft 25 and the spline fitting portion 28 of the output shaft 25 and the sleeve yoke 27.

On the other hand, the outline of the screw pump type lubrication structure is as shown in FIG. 5, in which a communication portion 29 formed in a partition wall 23 between the transmission case 20 and the extension housing 21 is integrated with the output shaft 25. The screw pump 30 that rotates is provided. According to this, when the output shaft 25 is rotated, the lubricating oil in the oil sump portion 20A of the transmission case 20 is fed into the extension housing 21 along the screw groove of the screw pump 30, whereby the inside of the extension housing 21 is fed. Lubrication is performed.

Further, Japanese Patent Laid-Open No. 63-176871 discloses a lubricating structure in which both the oil guide type and the screw pump type are combined. In this lubrication structure, the interior of the extension housing is partitioned into two spaces, and the lubricating oil in the mission case is first introduced into one of the spaces in the extension housing by flowing down the passage forming member. The lubricating oil is sent from one space to the other space by the rotation of the screw pump. A bearing for the output shaft exists in the one space, and a fitting portion between the output shaft and the sleeve yoke exists in the other space.

[0008]

[Problems to be solved by the device]

 By the way, the above-mentioned oil guide type lubrication structure has the advantage that the structure is simple and inexpensive, but on the other hand, since it utilizes the natural flow of lubricating oil, it is not necessary to arrange the passage forming member. There is a problem of being restricted in layout.

Particularly, when the distance from the oil sump in the transmission case to the extension housing is long, it becomes extremely difficult to dispose the passage forming body, and this oil guide type lubrication structure can be applied. It may run out.

On the other hand, in the above-mentioned screw pump type lubrication structure, since the output shaft drives the screw pump to rotate, there is a possibility that drive loss may increase, and when the output shaft is not rotating, the lubricating oil May not be able to be fed, which may lead to lubrication failure. Further, if the output shaft rotates in the reverse direction when the vehicle moves backward, the lubricating oil may flow back from the extension housing into the transmission case, and the amount of oil required for lubrication cannot be secured.

Further, the lubrication structure disclosed in the above publication not only has the drawbacks of both types, but also has the problem that the structure is complicated and the cost is increased.

The invention of the present application has been devised under the above-mentioned circumstances, and there is a layout problem even if the distance between the oil sump in the mission case and the extension housing is long. An extension housing that can reliably supply the lubricating oil without causing it and that can always secure the amount of oil required for lubrication even when the output shaft is not rotating or is rotating in the reverse direction from the transmission case. The problem is to provide the lubrication structure of the.

[0013]

[Means for Solving the Problems]

 In order to solve the above problems, the present invention takes the following technical means.

That is, in an extension housing lubrication structure in which an extension housing is installed on the output end side of the mission case and the lubricating oil in the mission case is introduced into the extension housing, the extension housing extends from the mission case. In the extension housing, the opposite end portions of the inserted output shaft and the sleeve yoke that transmits the rotation of the output shaft to the propeller shaft are connected so as to be relatively movable in the axial direction and non-rotatable relative to each other. Is provided with a volume varying means for changing the space volume in the extension housing in accordance with the relative movement of the two in the axial direction, and at least two communicating portions for communicating the inside of the mission case and the inside of the extension housing are formed. On the side communication part, The first one valve that allows the flow of fluid into the housing is provided, and the second one valve that allows the flow of fluid into the transmission case is provided at the communication part on the other side. It is characterized in that the shaft and the sleeve yoke are provided with sealing means at their respective extending portions into the extension housing.

[0015]

[Function and effect of device]

 According to the lubrication structure of the extension housing according to the present invention, since the sealing means is attached to each extending portion of the output shaft and the sleeve yoke into the extension housing, the internal space of the extension housing is reliably exposed to the outside. It becomes a closed state.

Then, as the propeller shaft reciprocates in the axial direction due to rocking of the vehicle body or the like, the opposing ends of the sleeve yoke and the output shaft relatively move in the axial direction within the closed extension housing. Then, the volume varying means that operates by this relative movement increases or decreases the space volume in the extension housing.

In this case, when the space volume in the extension housing increases, the pressure in this space decreases, and one side on which the first one valve that allows the flow of the fluid into the extension housing is provided Lubricating oil is sucked into the extension housing from the inside of the transmission case through the communication part of. On the other hand, when the space volume in the extension housing decreases, the pressure in this space rises, but the lubricating oil sucked in as described above does not flow out from the communication part on the one side. Only the compressed air flows out through the communication portion on the other side where the second one valve that allows the flow of the fluid into the mission case is arranged. As a result, the liquid level of the lubricating oil in the extension housing rises, and the output shaft and sleeve yoke are immersed in the lubricating oil.

The axial reciprocating motion of the sleeve yoke is carried out at an appropriate frequency as the propeller shaft moves back and forth in the axial direction due to rocking of the vehicle body and the like. The change in volume inside the extension housing is also performed at an appropriate frequency. Therefore, the suction of the lubricating oil is performed to such an extent that the amount of the lubricating oil in the extension housing can be maintained at an appropriate amount.

In this way, according to the present invention, the spatial volume in the closed extension housing is increased or decreased by the axial relative movement of the output shaft from the inside of the mission case and the sleeve yoke of the propeller shaft, and thereby, Lubricating oil is introduced from the transmission case into the extension housing. Therefore, even if the output shaft does not rotate, lubricating oil can be supplied to the extension housing, and even if the extension housing is arranged with a long distance from the mission case, Since the two can be communicated with each other by using a flexible pipe or the like, it becomes possible to satisfactorily lubricate the extension housing while avoiding a problem in layout.

[0020]

[Explanation of Examples]

 An embodiment of a lubrication structure for an extension housing according to the present invention will be specifically described below with reference to the drawings.

First, a first embodiment of the present invention will be described with reference to FIGS. 1 and 2.

In the first embodiment, as shown in FIG. 1, the present invention is applied to a configuration in which an extension housing 3 is directly attached to a partition wall 2 on the output end side of a mission case 1.

In the internal space X of the extension housing 3, the opposite ends of the output shaft 4 extending from the mission case 1 and the sleeve yoke 5 extending from the propeller shaft side (not shown) are connected. ing.

The output shaft 4 is rotatably supported by the partition wall 2 via a bearing 6, and the output shaft 4 of the partition wall 2 is sandwiched between the output shaft 4 and the inner space Y of the mission case 1 on both upper and lower sides. Communication holes 7 and 8 that communicate with the internal space X of the tension housing 3 are formed.

In the lower communication hole 7 of the above two communication holes, a first one-way valve 9 that allows the flow of fluid into the extension housing 3 is provided, and in the upper communication hole 8, A second one-way valve 10 that allows a fluid flow into the mission case 1 is provided. The lower communication hole 7 communicates with an oil reservoir A in the mission case 1.

A seal means 12 that is in sliding contact with the outer peripheral surface of the output shaft 4 is mounted in the shaft hole 11 of the partition wall 2 that is an extension portion of the output shaft 4 into the extension housing 3, and the sleeve yoke. A seal means 14 with which the outer peripheral surface of the sleeve yoke 5 is slidably contacted is mounted in the shaft hole 13 of the housing end wall 3a which is an extension portion of the sleeve yoke 5 into the extension housing 3.

The connecting portion B between the output shaft 4 and the sleeve yoke 5 is spline-fitted so that they can move relative to each other in the axial direction but cannot rotate relative to each other.

As shown in FIG. 2, a working space S is formed between the inner hole 5 a of the sleeve yoke 5 and the tip of the output shaft 4, and the working space S forms a spline. It communicates with the internal space X of the extension housing 3 via a communication groove 15 formed by cutting off part of the constituent teeth. The structure shown in FIG. 2 is the volume changing means 16 in this embodiment.

Next, the operation of the lubrication structure of the extension housing 3 having the above structure will be described.

During operation of the engine, the propeller shaft reciprocates in the axial direction due to rocking of the vehicle body, etc., and accordingly, the output shaft 4 and the sleeve yoke 5 relatively move in the axial direction. Become. As a result, the volume of the working space S shown in FIG. 2 increases or decreases, and the pressure of the internal space X of the extension housing 3 changes.

When the pressure in the internal space X of the extension housing 3 is reduced, the lubricating oil in the oil reservoir A in the mission case 1 passes from the communication hole 7 below the partition wall 2 to the first one-way valve 9 Through the inner space X of the extension housing 3. Further, even if the pressure in the internal space X rises, the lubricating oil in the extension housing 3 does not flow back through the first one-way valve 9, and the communication hole 8 above the partition wall 2 causes the second one-way valve to flow. Only compressed air flows out through 10.

Along with this, the lubricating oil is appropriately supplied to the internal space X of the extension housing 3, and the liquid level of the lubricating oil in the internal space X rises. Therefore, the bearing 6 of the output shaft 4 and the periphery of the connecting portion between the output shaft 4 and the sleeve yoke 5 are always filled with the lubricating oil, and the lubrication of each of these portions is favorably performed.

In particular, since the lubricating oil is supplied from the inside of the transmission case 1 to the inside of the extension housing 3 by utilizing the relative movement of the output shaft 4 and the sleeve yoke 5 in the axial direction as described above, Even if the output shaft 4 is reversely rotated or non-rotated, the lubricating action is performed without any trouble. As a result, even if the output shaft does not rotate as in the case of a part-time 4WD transfer, for example, a good lubrication action is performed.

FIG. 3 shows a second embodiment of the present invention. The difference between the second embodiment and the first embodiment is that the internal space X of the extension housing 3 and the mission case 1 are different from each other. That is, the oil sump portion A and the oil sump portion A are arranged so as to be separated from each other in the longitudinal dimension.

Therefore, in the second embodiment, two communication paths 7x and 8x communicating with the inside of the mission case 1 from the partition wall 2 defining the internal space X of the extension housing 3 are provided. The first one-way valve 9 and the second one-way valve 10 having the same directionality as described above are arranged on the paths 7x and 8x. The lower communication path 7x is composed of, for example, a flexible hose.

In the lubrication structure of the extension housing 3 shown in FIG. 3, the same components as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

According to the second embodiment, not only the same operational effects as those of the first embodiment can be obtained, but also the configuration, which is impossible with the conventional oil guide type or screw pump type, that is, It can be applied to a configuration in which the extension housing 3 is separated from the oil sump A of the mission case 1. This also avoids layout problems with the engine.

In the above embodiment, the volume varying means 16 has a structure as shown in FIG. 2. However, even if the structure shown in FIG. 2 is not adopted, the sleeve yoke having a diameter larger than that of the output shaft 4 is used. The volume of the internal space X of the extension housing 3 is changed by the axial movement of the extension housing 5, and therefore the volume varying means may have only this configuration. Further, the volume varying means can be configured by attaching a diaphragm or the like to the sleeve yoke 5.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing a first embodiment of a lubrication structure for an extension housing according to the present invention.

FIG. 2 is a vertical cross-sectional side view of a main portion showing the configuration of the volume varying means of the first embodiment.

FIG. 3 is a vertical sectional side view showing a second embodiment of a lubrication structure for an extension housing according to the present invention.

FIG. 4 is a vertical sectional side view showing a conventional example.

FIG. 5 is a vertical sectional side view showing a conventional example.

[Explanation of symbols]

 1 mission case 3 extension housing 4 output shaft 5 sleeve yoke 7 communication part (communication hole) 8 communication part (communication hole) 7x communication part (communication path) 8x communication part (communication path) 9 first one valve 10 second One-way valve 12 Sealing means 14 Sealing means 19 Volume changing means

Claims (1)

[Scope of utility model registration request] 1. A lubrication structure for an extension housing, wherein an extension housing is installed on the output end side of the mission case, and lubricating oil in the mission case is introduced into the extension housing, the extension structure extending from the mission case. The output shaft and the opposed end portion of the sleeve yoke that transmits the rotation of the output shaft to the propeller shaft are connected in the extension housing so as to be relatively movable in the axial direction and non-rotatable.
The connecting portion is provided with a volume changing means for changing the space volume in the extension housing in accordance with the relative movement of the two in the axial direction. A first one valve that allows the flow of fluid into the extension housing is provided in the communication portion on one side, and a second one that allows the flow of fluid into the transmission case is provided in the communication portion on the other side. A lubrication structure for an extension housing, characterized in that a one-way valve is provided, and sealing means is attached to respective extending portions of the output shaft and the sleeve yoke into the extension housing.