JPH02286924A - Rotation difference responding type joint - Google Patents

Abstract

PURPOSE:To miniaturize a device by forming at a rotor member inclination fluid passages which have fluid opening portions at positions where inclination fluid passages cross two surfaces A.B respectively which meet at right angles with a rotary shaft, within the range of the axial width of a fluid chamber provided with a cam body. CONSTITUTION:An inclination balance oil passage 60 is connected with cylinder chambers 50, 50 which make volume change in phase, and cylinder chamber opening portions 60a, 60b are provided at positions where the inclination balance oil passage 60 crosses two surfaces A, B which meet at right angles with a rotary shaft. A plurality of inclination balance oil passages 60 are housed so as not to interfere with each other, in the axial width of a rotor 30. As a result, the miniaturization of a device can be accomplished as the width of the inside portion where oil passages are formed, out of the rotor 30 becomes such a rotor axial width whose degree is that of an axial width which forms two parallel oil passages. Also, the enlargement of the rotor axial width by means of a regulator oil passage 80 is prevented as the regulator oil passage 80 has such a constitution that there is no rotary shaft direction overlap with the inclination balance oil passage 60.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention is applied to the engine drive system of a vehicle as a differential limiting device or a driving force distribution device, and the present invention is applied to a vehicle engine drive system as a differential limiting device or a driving force distribution device. The present invention relates to a rotation difference sensitive joint that changes the driving force distribution ratio by converting fluid pressure into differential limiting torque or driving force distribution torque.

(Prior art) Conventionally, as a rotation difference sensitive type joint, for example, JP-A-63
A device as described in Japanese Patent No.-62635 is known.

This conventional source includes a housing member having a cam surface on its inner surface, a rotor member having a radially arranged cam body that reciprocates in the radial direction while circumferentially contacting the cam surface by relative rotation, and a cam body formed on the rotor member. It includes a fluid path formed to communicate fluid chambers arranged opposite to each other whose volume changes in the same phase as the body reciprocates, and an orifice provided in the fluid path that converts the discharged fluid into fluid pressure by suppressing its flow. A differential rotation sensitive joint is shown.

(Problem to be Solved by the Invention) However, in such conventional rotation difference sensitive joints, the fluid passages that communicate the fluid chambers arranged opposite to each other are parallel fluid passages perpendicular to the rotation axis. As the number of fluid chambers increases, the axial width of the rotor member must increase due to the plurality of parallel fluid passages arranged at predetermined intervals to avoid interference with each other. However, there was a problem in that the rotor member became large and lacked compactness as a joint.

For example, if the number of cam bodies is increased to 6, 8, 10, 12, etc. in order to increase the transmission torque capacity or stabilize the characteristics, the number of parallel fluid paths will also be 3 or 4. , 5 pieces, 6 pieces・
..., and along with this increase, the axial width of the rotor member required for the parallel fluid path also increases.

The present invention was made in view of the above-mentioned problems, and an object of the present invention is to develop a rotation differential sensitive joint that can be made smaller and more compact despite an increase in the number of cam bodies.

(Means for Solving the Problems) In order to solve the above problems, in the rotation difference sensitive joint of the present invention, a first rotation shaft and a second rotation shaft that are coaxially arranged and rotate relative to each other, and the first rotation shaft a housing member provided at the shaft end of the shaft and having a cam surface on its inner surface; and a radial arrangement provided at the shaft end of the second rotating shaft, which reciprocates in the radial direction while circumferentially contacting the cam surface due to relative rotation. A fluid passage formed in the rotor member to communicate a rotor member having a cam body with a fluid chamber whose volume changes in the same phase as the cam body reciprocates, the fluid chamber having an axis in which the cam body is provided. An inclined fluid path is provided in the inclined fluid path, and the fluid chamber opening is at the intersection of two planes perpendicular to the rotation axis within the range of the direction width. The means is characterized by comprising an orifice member for conversion.

(Function) When manufacturing differential rotation sensitive joints, the rotor members are
An inclined fluid path is formed between two planes orthogonal to the rotating shaft within the axial width of the fluid chamber in which the cam body is provided, with the fluid chamber openings at the intersections of the two planes.

Therefore, even if there is an increase in the number of fluid passages communicating fluid chambers whose volume changes in the same phase as the cam bodies reciprocate as the number of cam bodies increases, the range of two planes perpendicular to the rotation axis Inside,
In other words, a plurality of inclined fluid passages are formed within a range approximately equal to the axial width of two parallel fluid passages, without interference with each other.

In addition, when using a rotation difference sensitive joint, when there is no relative rotation between the first rotation axis and the second rotation axis, there is no reciprocating movement of the cam body and no change in volume of the fluid chamber occurs, so in principle, the torque transmission effect is reduced. does not indicate.

However, when relative rotation occurs between the first rotation axis and the second rotation axis, the cam body that is in contact with the cam surface reciprocates in the radial direction due to this relative rotation. When the volume of the cam is reduced, the pressure inside the fluid chamber increases due to the flow resistance caused by the orifice member, and the fluid pressure obtained by multiplying this generated fluid pressure and the pressure-receiving area of the cam body becomes a force that presses the cam body against the cam surface, and this pressure The asterisk indicates a torque transmission effect in which the force becomes a transmitted torque.

This transmission torque characteristic is a characteristic that increases as the relative rotational speed difference increases, and the higher the degree of flow suppression by the orifice member, the higher the gain with respect to the relative rotational speed difference becomes.

(Example) Hereinafter, the present invention will be explained based on embodiments shown in the drawings.

First, the configuration of the embodiment will be explained.

The embodiment is an example in which the rotational difference sensitive joint of the present invention is applied as a differential limiting device, and as shown in FIG. A rotational difference-sensitive differential limiting device 2 is combined in a built-in state.

The differential device 1 includes a differential case 10 into which driving force is input via a drive pionion 3 and a ring gear 4, a binion 12 rotatably supported via a binion shaft 11, and a binion 12 that is rotatably supported via a binion shaft 11. A pair of side gears 13 and 14 that mesh with each other, and the side gear 1
3 and 14, two output shafts 15 and 16 (a first rotation shaft and a second rotation shaft) are provided.

The driving force is equally distributed to the output shafts 15 and 16 when no relative rotation occurs, and when relative rotation occurs, the driving force is transmitted by the differential limiting torque by the rotation difference sensitive differential limiting device 2. is transmitted from the high rotation side to the low rotation side.

As shown in FIGS. 1 and 2, the rotational difference sensitive differential limiting device 2 is connected to one of the output shafts 15 and 16.
The cam surface 21 formed on the inner surface of the cam housing 20 (housing member) spline-coupled to the rotor 30 (rotor member) spline-coupled to the other output shaft 16, and the cam surface 21 formed on the rotor 30 (rotor member) spline-coupled to the A radially arranged driving piston 40 (cam body) that reciprocates in the radial direction while surrounding the circumference, and a cylinder chamber 50 (fluid chamber) that changes in volume as the driving piston 40 reciprocates.
and a cylinder chamber 50.5 arranged oppositely and whose volume changes in the same phase.
an inclined balance oil passage 60 (inclined fluid passage) that communicates with
An orifice 90 ( orifice member).

The cam housing 20 is provided via a cam housing cover 22 spline-coupled to the output shaft 15, and has a cam surface 21 formed on its inner surface and a side gear 14 formed on its side surface. That is, output shaft 1
5, the cam housing cover 22, the cam housing 20, and the side gear 14 are integrally rotating members.

The rotor 30 is spline-coupled to the output shaft 16 and inserted into the cam surface 21 of the cam housing 20, and is arranged at six positions facing the cam surface 21 at equal intervals in the radial direction. A cylinder hole 31 is formed in.

The driving piston 40 is connected to the cylinder hole 31.
On the other hand, six cam members are provided in an oil-tight state by a seal ring 41, and the circumferential surface with the cam surface 21 is formed into a spherical surface to ensure smooth contact movement and high Hertzian contact stress.

The cylinder chamber 50 is formed between the cylinder hole 31 and the driving piston 40 so that the chamber volume changes depending on the stroke position of the piston 40.

The inclined balance oil passage 60 is connected to the driving piston 4.
0 is within the range of the diameter of the cylinder hole 31 in which the diameter of the rotor is provided, and is opposed to two surfaces A and B perpendicular to the rotary axis, which are set at an interval M in the rotor axial direction that is narrower than the diameter of this hole. The position where one chamber bottom surface of the cylinder chamber 50 intersects surface A is defined as a cylinder chamber opening 60a, and the position where the other chamber bottom surface and surface B intersect is defined as a cylinder chamber opening 60b, and one inclined balance oil passage 60 is formed. and the rotor axial width N
The three inclined balance oil passages 60 are formed so as to fit therein without interfering with each other.

The accumulator chamber 70 is a chamber that temporarily stores and releases hydraulic oil to absorb an increase or decrease in the amount of oil. 72
and a spring 73 interposed between.

Incidentally, the accumulator piston 71 is provided with a piston seal 74, and a relief hole 75 is opened in the radial direction in the rotor 30 at the position where the piston seal 74 is provided, so that the accumulator chamber 70 exceeds the set pressure. When the accumulator piston 71 moves rightward in the drawing, the relief hole 75 communicates with the accumulator chamber 70 and functions as a relief valve to release hydraulic oil.

The regulator oil passage 80 is an oil passage provided for adjusting the oil pressure of the cylinder chamber 50, and communicates the accumulator chamber 70 and each cylinder chamber 50 via one-way valves 81, so that the driving piston 40 can be moved out. Pressurized hydraulic oil is supplied from the accumulator chamber 70 to each cylinder chamber 50 when the cylinder chamber pressure becomes lower than the accumulator chamber pressure and the one-way valve 81 opens.

As shown in FIG. 3, the regulator oil passage 80 is formed with an offset amount ○ in the direction perpendicular to the rotation axis from the inclined balance oil passage 60.
By avoiding overlap in the rotation axis direction, the rotor axial width N is prevented from increasing due to the regulator oil passage 80.

The orifice 90 is formed in each of the three axially branched oil passages 61 extending from the inclined balance oil passage 60 to the accumulator chamber 70, and has a flow passage cross-sectional area larger than that of the cylinder chambers 50 and 50 of the two opposing cylinders. One orifice 90 provides flow resistance to the hydraulic oil.

Next, the operation of the embodiment will be explained.

(a) During non-relative rotation When running in parallel at low to medium speeds on a dry asphalt road, etc., and when there is no rotational speed difference between the left and right wheels connected to the output shaft 15, 16, the case cover 2 and rotor 3
0, and the driving piston 40 does not reciprocate in the radial direction, so the differential case 10
Is the engine driving force input from the output shaft? 5.18 will be equally distributed.

However, even when relative rotation does not occur between the left and right wheels, when driving straight on a highway at high speed, the driving piston installed in the rotor 30 rotates at high speed as the output shaft 15, 16 rotates. Centrifugal force acts on 4Q, and this centrifugal force causes the driving piston 40
is pressed against the cam surface 21, and a differential limiting torque is generated.

Therefore, when traveling straight at high speed, the differential limiting function is exerted to some extent, and the stability of straight traveling at high speed on expressways can be improved.

(b) When relative rotation occurs When a difference in rotational speed occurs between the left and right wheels connected to the output shaft 15° 16 when driving on a rough road or when one wheel is stuck, the case cover 20 and rotor 30 also rotate relative to each other. occurs, and due to this relative rotation, the driving piston 40 in circumferential contact with the cam surface 21 reciprocates in the radial direction, and when attempting to reduce the volume of the cylinder chamber 50 by moving toward the center of the rotation axis during this reciprocating movement, The pressure inside the cylinder chamber 50 increases due to the flow resistance caused by the flow restriction by the orifice 90, and the hydraulic pressure obtained by multiplying this generated hydraulic pressure and the pressure receiving area of the piston 40 becomes a force that presses the driving piston 40 against the cam surface 21, and this In pressing, the force acts as a differential limiting torque, and the differential is limited so that the distribution of driving force is smaller on the high-speed rotation side and larger on the low-speed rotation side.

The differential limiting torque characteristics of the embodiment device are as follows:
As shown in the solid line characteristic in the figure, the left and right wheel rotational speed difference ΔNRL
In contrast, the differential limiting torque TLSD exhibits a characteristic that increases in a quadratic function curve.

In addition, when the vehicle speed V is high, such as when driving at high speed, 96 transmission torques are added due to the centrifugal force applied to the driving piston 40, as shown by the dotted line characteristics in FIG. 4, corresponding to the magnitude of the vehicle speed V. It shows the characteristics that have been

As described above, the rotational difference sensitive differential limiting device 2 of the embodiment provides the following effects.

■ The fluid path that communicates the cylinder chambers 50 and 50 whose volume changes in the same phase is an inclined balance oil path 60, and the position that intersects two planes A and B perpendicular to the rotation axis is the cylinder chamber opening 6.
As 0a and 60b, the three inclined balance oil passages 60 are configured to fit within the rotor axial width N without interfering with each other, so the inner part of the rotor 30 where the oil passages are formed is 2.
The axial width N of the rotor is approximately the same as the axial width of a parallel oil passage, and the rotation difference sensitive differential limiting device 2 can be made smaller and more compact.

For example, the number of driving pistons 40 may be increased due to a design change, and along with this, the inclined balance oil passage 6 may be increased.
Even if there is an increase in the number of 0's, the width can be handled without increasing the axial width of the rotor.

■ Although the regulator oil passage 80 is formed at a position overlapping with surface B, it is formed with an offset amount ○ in the direction perpendicular to the rotation axis with respect to the inclined balance oil passage 60, so the inclined balance oil passage 60 overlap in the rotation axis direction is avoided, and the rotor axial width N due to the regulator oil passage 80 is reduced.
The expansion of can be prevented.

That is, due to the synergistic effect with the effect (2) above, the axial width N of the rotor can be set narrowly, and the rotation difference sensitive differential limiting device 2 can be made smaller and more compact.

■ Since one orifice 90 is provided for the inclined balance oil passage 60 that communicates the cylinder chambers 50 and 50 of two opposing cylinders, the differential limit is the same as when one orifice is provided for one cylinder chamber. The cross-sectional area of the orifice 90 can be made larger than the cross-sectional area of the orifice when obtaining torque characteristics, and as a result, the influence of contamination (dust, etc.) can be avoided.

Although the embodiment of the present invention has been described above in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and the present invention may be modified even if there are design changes within the scope of the gist of the present invention. included.

For example, in the embodiment, an example of application in which a rotation difference-sensitive joint is used as a rotation difference-sensitive differential limiting device is shown. It can also be used as a restriction device, and is also a driving force distribution system that changes the front and rear wheel drive force distribution according to the rotational speed difference △NFH between the front and rear wheels! It can be adapted as well.

Further, in the embodiment, an example is shown in which six driving pistons are provided as cam bodies, but the number is not limited to the embodiment, and may be eight or ten.

Of course, it is also possible to have 12 pieces, etc.

In addition, although a fixed orifice is shown in the embodiment, it is not limited to this fixed orifice. For example, when high relative rotation continues for a long time, the orifice opening degree may be fully closed by sensing the hydraulic oil temperature. Alternatively, it may be a variable orifice whose opening degree is gradually changed depending on the relative rotational speed, fluid chamber pressure, etc.

(Effects of the invention) As explained above, in the rotation difference sensitive joint of the invention, a fluid chamber is formed in the rotor member to accommodate a fluid chamber whose volume changes in the same phase as the cam body reciprocates. Since the fluid path is an inclined fluid path with the fluid chamber opening at the intersection of two planes perpendicular to the rotation axis within the axial width of the fluid chamber in which the cam body is installed, the cam The effect is that the rotation differential sensitive joint can be made smaller and more compact regardless of the increase in the number of bodies.

[Brief explanation of drawings]

1 is a longitudinal sectional plan view showing a rotational difference sensitive differential limiting device according to an embodiment of the present invention; FIG. 2 is a longitudinal sectional front view showing the rotational differential sensitive differential limiting device taken along line I-I in FIG. 1; FIG. 3 is a side view showing the rotor of the rotation difference sensitive differential limiting device, and FIG. 4 is a differential limiting torque characteristic diagram. 1...Differential device 2...-Rotation difference sensitive differential limiting device 10...Differential case 11...Pinion shaft 12...Pinion 13.14-...Side gear 15.16...Output Shaft (first rotating shaft, second rotating shaft) 20-・Cam housing (housing member) 21・-・
Cam surface 30... Rotor (rotor member) 40... Driving piston (cam body) 50...
Cylinder chamber (fluid chamber) 60... Inclined balance oil path (inclined fluid path) 70...
Accumulator chamber 80...regulator oil path

Claims (1)

[Claims] 1) A first rotating shaft and a second rotating shaft that are coaxially arranged and rotate relative to each other, and a housing member that is provided at the shaft end of the first rotating shaft and has a cam surface on its inner surface. , a rotor member having a radially arranged cam body that is provided at the shaft end of the second rotating shaft and reciprocates in the radial direction while circumferentially contacting the cam surface by relative rotation; A fluid path formed in a rotor member to communicate fluid chambers whose volume changes in the same phase, and which connects two surfaces perpendicular to the rotation axis within the axial width of the fluid chamber in which the cam body is installed. A rotation difference sensitive type characterized by comprising: an inclined fluid passage whose intersecting position is a fluid chamber opening; and an orifice member provided in the inclined fluid passage and which converts discharged fluid into fluid pressure by suppressing the flow of the fluid. Fittings.