JP3507835B2 - Mounting device for driving force transmission device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for mounting a driving force transmitting device which is disposed between two relatively rotatable members and transmits driving force between the two members. Things. [0002] Generally, in a four-wheel drive driving force transmitting device for transmitting torque between front and rear wheels, a front propeller shaft or a front propeller shaft is provided between a front propeller shaft and a rear propeller shaft. A driving force transmission device is arranged between the front wheel and the rear wheel differential device, and transmits the power of the engine from the front wheel side to the rear wheel side according to the differential rotation speed between the front wheel and the rear wheel. [0003] This type of driving force transmission device includes an outer case and an inner shaft that can rotate relative to each other. One of the outer case and the inner shaft is connected to a front propeller shaft, and the other is connected to a rear propeller shaft. Is done. By the way, in this type of driving force transmission device, an inner shaft is rotatably supported so as to penetrate the outer case, and the connection between the inner shaft and the propeller shaft or the differential device is generally performed by spline engagement. The connection between the case and the propeller shaft is made using a screw member. As the screw member in this case, a stud bolt is preferable in terms of space. As is well known, such a stud bolt has a stud-side screw portion and a nut-side screw portion at both ends of a round bar, and when two members are connected to each other, First, in a state where the implantation side screw portion is implanted in the screw hole of one member, the nut side thread portion is inserted into the hole of the other member, and then the nut is screwed into the nut side thread portion and the nut is tightened. . By tightening the nut, an axial shear load acts on the screw hole of one member, and an axial tensile load acts on the stud bolt. In some cases, the outer case is made of a material such as aluminum in order to reduce the weight of the driving force transmitting device. In such a case, it is assumed that the outer case is plastically deformed by the shear load in the axial direction due to the tightening of the stud bolt, so that the thread portion on the implantation side is loosened, and in the worst case, the stud bolt may fall off. Therefore, an object of the present invention is to provide a mounting device for a driving force transmission device that can reliably prevent the stud bolt from falling off even if the stud bolt is loosened. The present invention includes an outer case and an inner shaft that are relatively rotatable, and torque can be transmitted between the outer case and the inner shaft by differential rotation of the outer case and the inner shaft. An outer case of a driving force transmission device is attached to a flange portion connected to a propeller shaft by using stud bolts. The mounting device of the driving force transmission device has the stud bolts at both ends.
From the large-diameter male thread on the implantation side and this male thread on the implantation side
Also has a small-diameter nut-side male thread, and the large-diameter implant side
The male screw part is a screw hole engraved on the end face of the outer case.
Into the small-diameter nut-side male screw section.
The insertion hole formed in the flange portion is inserted, and the small
With a nut screwed into the male thread part on the nut side of the diameter.
Of the outer case by the nut
On the surface, formed on the flange
The inner diameter of the insertion hole thus set is the same as the outer diameter of the male thread on the implantation side.
It is set to be smaller than the outer diameter of the nut side male thread part . According to the above configuration, the stud bolt can be implanted in the outer case in advance, so that screw connection can be performed even when there is not enough space corresponding to the bolt length on the side of the flange portion. Also, even if the stud bolts implanted in the outer case are loosened, the stud-side male screw portion cannot pass through the insertion hole of the flange portion, so that the stud bolts can be reliably prevented from falling off. Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 4, the driving force transmission device 10 is disposed on a power transmission system path from the front wheel side to the rear wheel side in the FF vehicle, and the front wheel side is constantly driven, and the rear wheel side is driven when necessary. Things. The transaxle 12 mounted on one side of the engine 11 includes a transmission and a transformer, and outputs power from the engine 11 to the axle shaft 13 to drive the front wheels 14 and output to the first propeller shaft 15. The first propeller shaft 15 is connected to the second propeller shaft
When connected to the propeller shaft 16 and torque is transmitted to the second propeller shaft 16, power is output to the axle shaft 17 via the rear differential 27 and the rear wheel 18 is driven. FIG. 1 shows an example of the driving force transmitting device 10. The driving force transmitting device 10 includes an outer case 2.
1, an inner shaft 22 rotatably supported so as to pass through the inside of the outer case 21, pressure generating means 23 for generating a pressure corresponding to a differential rotation between the outer case 21 and the inner shaft 22, This pressure generating means 2
3 mainly includes a piston 24 to which the pressure generated at 3 is applied, and a multi-plate clutch 25 frictionally engaged by the pressing force of the piston 24. The inner shaft 22 has a sleeve shape, and has a spline portion 22A formed on the inner periphery thereof. The spline portion 22A is spline-fitted to the second propeller shaft 16. The outer case 21 is fixed to the rear end of the first propeller shaft 15 as described later. A cylindrical hollow hole 26 with a bottom is formed at one end of the outer case 21, and the open end of the hollow hole 26 is closed by an end cover 27 screwed into the open end so as to be position-adjustable. . Hollow hole 26
The piston 24 is slidably housed so as to define a space 28 between the end cover 27 and the end cover 27. The piston 24 engages with a spline formed on the inner periphery of the outer case 21 to rotate. Has been stopped. In the hollow chamber 26, a clutch chamber 29 is formed between the bottom surface of the outer case 21 and the piston 24, and a multi-plate clutch 25 is disposed in the clutch chamber 29. The multi-plate clutch 25 includes a plurality of outer plates 31 spline-engaged with the inner periphery of the outer case 21.
And a plurality of inner plates 32 spline-engaged with the outer periphery of the inner shaft 22, and the outer plates 31 and the inner plates 32 are arranged alternately. Thus, the clutch chamber 29 is filled with clutch lubricating oil. The end wall of the piston 24 and the end cover 2
The cylindrical space 28 formed between the end wall 7 and the end wall 7 has
A rotor 33 having a thickness slightly smaller than its width is housed so as to be able to slide. As shown in FIG. 2, the rotor 33 has a central portion spline-engaged with the outer periphery of the inner shaft 22 and a plurality of blades 3 extending in the radial direction.
3A. The space 28 is filled with a relatively high-viscosity viscous fluid made of silicon oil or the like. In the above configuration, when the rotor 33 rotates relative to the outer case 21, the viscous fluid filled in the space 28 is forcibly moved by the rotor 33 at a flow rate corresponding to the difference in rotation speed. However, at this time, an internal pressure proportional to the rotational speed difference of the rotor 33 is generated in the space 28 due to the viscous frictional action of the viscous fluid on both end walls of the piston 24 and the end cover 27. The principle of generation of such internal pressure is described in detail in, for example, JP-A-63-240429. By the internal pressure described above, the piston 24 is pressed by a pressure corresponding to the differential rotation, and acts on the multi-plate clutch 25. Therefore, the plurality of outer plates 31 and the inner plates 32 are frictionally engaged with each other with a pressing force corresponding to the pressure acting on the piston 24, and rotational torque is transmitted between the outer case 21 and the inner shaft 22. One end of the first propeller shaft 15 has a spigot portion 40 for centering.
A flange portion 40 having B is provided, and one end of the outer case 21 is attached to the flange portion 40 by a stud bolt 41 described later. Thereby, the engine 1
1 is transmitted to the outer case 21 via the first propeller shaft 15 at all times. [0015] The stud bolts 41
Book is arranged. As shown in detail in FIG. 3, both ends of these stud bolts 41 are provided with male threads 41 on the implantation side.
A and the nut-side external thread 41B are engraved, and the outer diameter d1 of the implant-side external thread 41A is larger than the outer diameter d2 of the nut-side external thread 41B. The stud bolt 41 has a stud-side male screw portion 41A which is screwed to the bottom of a screw hole 21A formed in the end surface of the outer case 21. On this occasion,
The implantation-side male screw portion 41A is set to have an axial length that completely fits in the screw hole 21A. The flange 40 has a plurality of circumferential through holes 40A through which the nut-side male threads 41B of the stud bolts 41 are inserted.
The hole diameter d3 of 0A is set larger than the outer diameter d2 of the nut-side male screw portion 41B and smaller than the outer diameter d1 of the implant-side male screw portion 41A (d1>d3> d2). That is, the insertion hole 40A of the flange portion 40 is set so that the nut-side male screw portion 41B can be inserted and the implant-side male screw portion 41A cannot pass through. Therefore, after the stud bolt 41 has the stud side male thread 41A implanted in the outer case 21, the nut side male thread 41B is inserted into the through hole 40A of the flange 40, and the centering is performed by the spigot 40B. The outer case 21 is joined to the first propeller shaft 15 by joining the flange portion 40 to the end surface of the outer case 21 and screwing the nut 42 into the nut-side male screw portion 41B in this state. As a result, the stud bolt 41
Even when the studs are loosened, the situation where the stud bolts 41 fall off can be reliably prevented. The driving force transmission device 10 constructed as described above
, The first and second propeller shafts 15, 16
If relative rotation occurs between them, torque is transmitted. That is, when relative rotation occurs between these two shafts 15 and 16, the outer case 21, the end cover 27 and the piston 14, which are integrally rotatably mounted on the first propeller shaft 15, and the second propeller shaft 16 integrally rotate. Relative rotation occurs between the inner shaft 22 and the rotor 15 which are mounted as possible. Therefore, in the pressure generating means 23, the viscous fluid is forced to flow at a speed proportional to the relative rotation by the action of the blades 33A, and gradually from the upstream end to the downstream end of each blade 33A. An increased pressure distribution occurs. The pressure increasing portion of this pressure distribution increases in proportion to the differential rotation speed, and presses the piston 14 in the axial direction.
As a result, the piston 14 presses the multi-plate clutch 25,
The outer plate 31 and the inner plate 32 are frictionally engaged. As a result, in the multi-plate clutch 25, torque proportional to the differential rotation speed is transmitted from the outer case 21 to the inner shaft 22, and the vehicle enters a four-wheel drive state. In the above-described embodiment, a driving force transmission device that transmits torque between outer case 21 and inner shaft 22 by frictionally engaging multiple disc clutch 25 by a pressure generating action due to the relative rotation of rotor 33 is described. As described above, the present invention is applicable to a driving force transmission device having any configuration such as a viscous coupling or a pump coupling. Further, in the above-described embodiment, the outer diameter d of the externally threaded portions 41A and 41B on the implantation side and the nut side is set.
1, d2 and the inner diameter d3 of the insertion hole 40A of the flange portion 40
Has been described with respect to the relationship d1>d3> d2, but the insertion hole 40A does not necessarily have to be a perfect circle, and the insertion hole 40A is essentially the nut-side male screw portion 41B.
Is only required to be configured so that it can be inserted and cannot pass through the implantation-side male screw portion 41A. As described above, in the present invention,
Large-diameter implant that is screwed into the outer case screw hole and fixed
Insert the male screw part on the side and the insertion hole formed in the flange part
Nut on the nut side
Stud bolts with flanges, through holes in flanges
The inner diameter of the stud bolt is
Smaller than outer diameter, larger than outer diameter of nut side male thread
Because it is Ku was set configuration, event implantable side male screw portion is A
Also loose to screw holes of Utakesu, by the flange portion
This has the effect of reliably preventing the stud bolt from falling off.

[Brief description of the drawings] FIG. 1 is a diagram showing an attached state of a driving force transmission device. FIG. 2 is a sectional view taken along line AA of FIG. FIG. 3 is an enlarged detail view showing a part of FIG. 1; FIG. 4 is a diagram showing a four-wheel drive system. [Explanation of symbols] 10 Driving force transmission device 15,16 Propeller shaft 21 Outer case 22 Inner shaft 40 Flange 40A insertion hole 41 stud bolt 41A Implanted Side Male Thread 41B Nut side male thread 42 nut

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B60K 17/34-17/35 F16H 57/02 F16B 5/00 F16B 39/00

Claims (1)

(57) [Claim 1] A driving force capable of transmitting a torque between the outer case and the inner shaft by a differential rotation of the outer case and the inner shaft, the outer case and the inner shaft being rotatable relative to each other. An outer case of the transmission device is a mounting device of a driving force transmission device that is coupled to a flange portion connected to a propeller shaft using a stud bolt, and the stud bolt has a large-diameter stud-side external thread portion at both ends ,
Use a male thread on the nut side smaller in diameter than the male thread on the implantation side.
The large-diameter implant-side external thread portion is provided in the outer case.
Screwed into the screw hole engraved on the end face of
Diameter nut side male screw part is formed on the flange part
The insertion hole is inserted and the small-diameter nut side male thread
A nut to be inserted into the flange.
Part is fixed to the end face of the outer case.
The inner diameter of the insertion hole formed in the flange portion,
Smaller than the outside diameter of the male thread on the implantation side,
A mounting device for a driving force transmission device set to be larger than the outer diameter of the part .