JPH0312582Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to an improvement of a hub lock used in four-wheel drive vehicles and the like.

[Conventional technology]

Here, the hub lock refers to a freewheel hub clutch, and the hub lock disconnects the wheels and the drive shaft as necessary in a four-wheel drive vehicle that can switch between two-wheel and four-wheel drive modes at any time. It is a device for joining or joining. The hub lock cuts off the rotation of the drive shaft when two wheels are running, solving problems in terms of noise and fuel consumption.

As a hub lock of this kind, JP-A-56-
There are those disclosed in Japanese Patent Application Laid-open No. 10828 and Japanese Patent Application Laid-Open No. 56-31530.

These have a clutch member rotationally integrated with the drive shaft side, and a clutch portion that engages with the clutch portion of the member when the drive shaft rotates and the clutch member is displaced in the axial or circumferential direction. The vehicle has a housing fixed to the wheel-side hub with bolts, and a cover that closes an opening at one end of the housing.

[Problem that the invention attempts to solve]

However, in the conventional case, the housing having the clutch portion is responsible for the engagement and disengagement of the clutch, and therefore needs to be constructed of a strong member such as steel. This results in an increase in the weight of the unit and an increase in cost. Further, since the conventional cover is fixed to the outer periphery of the end portion of the housing with bolts or the like, it is necessary to provide seal portions at two locations: the hub and the housing, and the housing and the cover, and it is not easy to retain the seal portions.

[Means and actions for solving problems]

The present invention has been developed in view of the above, and it is possible to reduce the weight of the unit by rotatably engaging the housing and the cover, and by allowing the cover to surround the housing and be directly fixed to the hub. This provides a hub lock with improved sealing performance.

〔Example〕

The hub lock of the present invention will be explained below.

FIG. 1 shows a first embodiment of the present invention, in which a drive gear 2 is spline-engaged with the tip of a drive shaft 1 that receives rotational driving force from an engine (not shown). A spline and a radial pawl are provided on the outer periphery of the drive gear 2, and an axially movable slite gear 3 is engaged with the spline. A spline and a clutch portion are formed on the outer periphery of the slide gear 3, and a cam 5 that is movable in the axial direction and has a cam portion that projects inward in the axial direction is engaged with the spline. Slide gear 3 and drive gear 2
Retainers 6a and 6b, whose inner peripheries are supported by the drive gear 2 and are rotatable relative to the drive gear 2, are disposed between the retainers 6a and 6b. The retainer 6b is formed with a grooved cam portion that engages with the cam portion of the cam 5 and an axial protrusion that engages with a first brake member 7, which will be described later. The first brake member 7 is disposed axially inward of the retainer 6b, and has a first protrusion that engages with a protrusion of the retainer 6b on the inner circumferential side, and a second protrusion that engages with a claw of the drive gear. It also has a conical friction surface on its outer periphery. A second brake member 11 having a friction surface that contacts the friction surface of the first brake member 7 is fixed to the fixed spindle 9, and the first brake member 7 and the second brake member 11
and form a brake mechanism. A shift spring 14 is mounted between the clutch portion of the slide gear 3 and the cam 5, and a return spring 13 is mounted between the retainer 6a and the cam 5. A clutch portion 4a is provided on the outer periphery of the retainer 6a so as to be relatively rotatable.
A housing 4 made of steel is provided, in which a cylindrical portion 4b and a cylindrical portion 4b are integrally formed. On the outer periphery of the cylindrical portion 4b, a concavo-convex shape made of, for example, a spline portion 23 is formed. A cover 15 made of a light metal such as aluminum, which is integrally formed with a cup-shaped body 15a that surrounds the housing 4 and has one end closed, and a flange portion 15b that extends to the body 15a. is provided. The inner peripheral surface of the cover 15 is provided with a spline portion 2 having an uneven shape that meshes with a spline portion 23 having an uneven shape formed on the outer peripheral surface of the cylindrical portion 4b.
4 is formed, the spline portion 24 and the spline portion 23 are spline-coupled, and the housing 4 is connected to the circlip 25 and the main body 15a of the cover 15.
The axial position is regulated between the inner surface of the
The cover 15 is fastened to the wheel hub 20 with bolts 19.

The operation of the hub lock constructed in this way will be explained.

Figure 1 shows two-wheel drive condition (hereinafter referred to as "2WD")
When switching to four-wheel drive mode, the driver operates the shift lever provided on the driver's seat to switch from 2WD to 4WD, and when the vehicle is moved, the drive shaft 1 begins to rotate. Then, the drive gear 2 and the slide gear 3 rotate together with the cam 5. Here, the cam 5 is connected to the retainer 6 by the cam portion.
Because the retainer 6 is fitted into the groove-shaped cam part b.
b also rotates, and due to this rotation, the protrusion of the retainer 6b and the first protrusion of the first brake member 7 engage and try to rotate the first brake member 7, but the friction surface of the first brake member 7 The first brake member 7 and the retainer 6b are braked, and there is a relative gap between the cam 5 and the retainer 6b, as the cam 5 and the retainer 6b are braked. Rotation occurs. This relative rotation generates an axial thrust force between the cam 5 and the retainer 6b, and the cam 5 moves to the right in FIG. 1 while compressing the shift spring 14 and the return spring 13. Therefore, the slide gear 3 also moves to the right due to the elastic force of the shift spring 14,
The clutch portion of the slide gear 3 and the clutch portion 4a of the housing 4 are coupled together. As a result, the drive shaft 1 and the housing 4 are combined to provide 4WD.

Next, when changing from 4WD to 2WD, switch the shift lever from 4WD to 2WD and move the vehicle slightly in the opposite direction to the direction in which it has been traveling. Slide gear 3 and cam 5 will rotate from the housing 4 side. The cam portion of the cam 5 falls into the groove-shaped cam portion of the retainer 6b due to the elastic force of the return spring 13, and the slide gear 3 accordingly moves to the left to release the clutch engagement state and obtain 2WD. .

In the above configuration, by constructing the housing 4 (consisting of the clutch part 4a and the cylindrical part 4b) from steel, durability is ensured at the sliding part with the retainer 6a and during clutch on/off with the slide gear 3. can. In addition, the part that does not require great strength, such as the flange part of the conventional housing, forms part of the cover as the flange part 15b of the cover, and is directly fixed to the hub with bolts so as to surround the housing 4.
It can be constructed from light metal such as aluminum, and can be molded and
In addition to being easier to process and lighter in weight, it is also possible to improve sealing performance since the hub and cover flange are sealed only. In addition, if it becomes necessary to change the design or color of the externally exposed part (only the cover 15 in this invention) in order to match the shape of the hub, etc., the part that needs to be replaced is the cover 15.
Therefore, the other parts (housing, that is, the necessary minimum strength parts including the clutch part 4a and the cylindrical part 4b) can be used as they are as common parts (interchangeable parts). At this time, since the cover 15 made of light metal such as aluminum is easy to mold and process, it is easy to manufacture a new one that matches the shape of the hub.
There is an advantage that there is no need to newly form or process steel parts that are difficult to form or process, such as the cylindrical portion 4a or the cylindrical portion 4b. Note that the spline portion 24 of the case 15 is similar to the spline portion 2 of the housing 4b.
3 and does not slide or rotate relative to each other, so even if it is made of light metal such as aluminum, there will be no strength problem.

Next, FIGS. 2 and 3 A, B, and C show other embodiments of the present invention, and parts similar to those in FIG. 1 are designated by the same reference numerals and detailed explanations are omitted. The bolt 19 connects the wheel hub 20 and the flange portion 15b of the cover.
This shows a type of hub lock that is fastened together with the road wheel (rim) 26. In this hub lock, the contact area between the road wheel 26 and the cover 15 (made of light metal such as aluminum) is dented by the tightening force of the bolts 19, so there is a risk that the tightening force of the bolts will decrease and loosening may occur. be. Looseness of this portion causes misalignment and wobbling of the internal parts (particularly the clutch portion 4a and the slide gear 3), resulting in malfunctions and malfunctions. In order to prevent the tightening portion from loosening due to a dent in the flange portion 15b due to the load wheel 26 being excessively pressed against the flange portion 15b, a gap between the flange portion 15b and the road wheel 26 is provided. The embodiment shown in FIGS. 2 and 3A has a reinforcing washer 27 interposed therebetween. 3B and 3C are explanatory views of the structure of the washer 27, which is made of steel and has an outer shape that matches the washer seating recess 15c formed in the flange portion 15b of the cover. The curved part of the road wheel 26 is the washers 2.
By configuring it so that it abuts on 7, it is possible to prevent the occurrence of loosening due to the occurrence of the dent. Furthermore, since the flange portions 15b of the cover have a petal shape that protrudes toward the outer diameter at intervals, the portions between the respective protruding portions are punched out, and the weight can be reduced accordingly. In addition, whether the flange part is petal-shaped as in this example or disc-shaped, manufacturing is easy because it can be manufactured only by casting (no heat treatment required), and unlike steel, it does not require heat treatment after molding. There is no risk of deformation (waviness) occurring due to heat treatment in cases where it is required. Further, in order to prevent the bolt holes 21 of the flange portion 15b from being worn out, a reinforcing member 28 as shown in FIG. 4 may be used.

[Effect of idea]

As explained above, according to the hub lock of the present invention, the housing and the cover are rotationally engaged, and the cover surrounds the housing and is directly fixed to the hub with bolts, so the housing part is downsized. The weight of the unit can be reduced and the sealing performance can be improved. Furthermore, since the internal unit can be made common, there is a degree of freedom in that it can be applied to various things by simply changing the cover, which has the effect of reducing costs and improving versatility.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram of the configuration of one embodiment of the present invention;
Figures 4 to 4 show the configuration of other embodiments of the present invention, and Figure 2 is a vertical cross-sectional view of the entire hub lock, and Figure 3 is a longitudinal sectional view of the entire hub lock.
Figure A is a front view of the cover, Figures 3B and 3C are front and side views of the washers, and Figure 4 is an explanatory diagram of the bolt hole reinforcing member. Explanation of symbols, 1...Driveshaft, 2...
Drive gear, 3...Slide gear, 4...Housing, 4a...Clutch part, 4b...Cylindrical part,
5...cam, 6a, b...retainer, 7...first
Brake member, 8... Elastic member, 9... Spindle, 10... Nut, 11... Second brake member, 13, 14... Spring, 15... Cover, 15a... Cylindrical body, 15b... Flange Part, 19...Bolt, 20...Wheel hub.

Claims (1)

[Claims for Utility Model Registration] A cylindrical housing having a clutch portion on the inner periphery, a cover that closes an opening at one end of the housing, and a clutch portion capable of being engaged with the clutch portion of the housing, a slide gear that is disposed non-rotatably but movable in the axial direction on the drive shaft side and moves in the axial direction against a spring mechanism to engage the housing in a clutch; A cam that compresses the spring mechanism as it moves; a retainer having a cam portion that engages with the cam to move the cam in the axial direction; and a brake mechanism that applies braking force to the retainer. In the hub lock, the housing has an uneven portion on the outer periphery, and the cover includes a cup-shaped portion with one end closed, a flange extending from the cup-shaped portion, and an uneven portion on the inner periphery. , has a concavo-convex shaped part that engages with the concave-convex shaped part of the housing, the cup-shaped part of the cover surrounds one end opening of the housing, and the concave-convex shaped part of the housing and the concave-convex part of the cover the outer circumference of the housing and the inner circumference of the cover are locked in a non-rotatable manner, and the housing is positioned on the cover in the axial direction, so that the housing and the cover are engaged with each other; A hub lock, characterized in that the flange portion of the cover and the hub body are fixed to each other via a fastening member.