JPS58163853A - Planet gearing with non-stage variable-speed control function - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention includes a housing, a drive shaft and a driven shaft extending through the housing, and a planetary wheel support mounted to the drive shaft for rotation by the drive shaft within the housing. , supported for rotation on said planetary wheel support by bearings and angularly spaced relative to each other about an axis of rotation of said planetary wheel support, a larger truncated portion; a smaller truncated body portion adjacent to the larger base of the body portion, the radially outer generatrix of the larger truncated body portion being aligned with the axis of rotation of the planet wheel support. a plurality of planetary wheels in the form of tapered rollers extending generally parallel to the housing; and a plurality of planetary wheels in the form of tapered rollers that are locked against rotation with the housing and whose inner surfaces overlap the surfaces of the larger truncated portions of the tapered planetary wheels. an adjusting annular member in contact and a device for adjusting axial movement of the adjusting annular member along a larger truncated portion of the tapered planet wheel; coaxially with the planet wheel support; a driven annular member rotatable and having a conical inner surface corresponding to a surface of the smaller truncated portion of the tapered planetary ring for rotating the driven shaft; The surface of the larger truncated part of the tapered planetary ring is brought into pressure contact with the corresponding conical surface of the driven annular member, and the inner surface of the adjusting annular member with the surface of the larger truncated part of the tapered planetary ring. The present invention relates to a planetary transmission device with a continuously variable speed control function including a device for pressing together.

Transmissions of the aforementioned type are described, for example, in U.S. Pat. No. 2,328
, No. 536, No. 2,343,840, No. 2,34
No. 2,071 and No. 3,667,109.

These transmissions are commonly referred to as "friction drives" and
It is based on the elastohydraulic theory of lubricants and takes advantage of the shear strength of the lubricant film between the surfaces of the transmission components that are in rolling contact. In fact, when high operating pressures are applied, the lubricant film undergoes a glass-like transformation, becoming solid-like, and the materials forming the parts in contact may yield elastically. It maintains a constant thickness and its shear strength transmits the driving force from the driving member to the driven member, while ensuring complete separation of irregularities in the surfaces of these members.

A major problem with these transmissions is that the transmission of high levels of power, such as those required for applications in the field of automotive traction, is difficult when the size and size of the transmission is reduced. . These difficulties arise primarily from the magnitude of the normal forces acting on the members in rolling contact.

In order to ensure the transmission of such high torques, these forces are assumed to be in the value of several tons, imposing significant loads on the support bearings of the tapered planet wheels, with the result that the service life of the transmission is completely unsatisfactory. becomes. These forces also roll and deform the members in contact, and, in combination with transmission dimensional and assembly tolerances, cause the tapered planetary wheels to kinematically operate at different contact radii, resulting in transmission ratios. This causes fluctuations in the planetary arrangement, overloads the contact surfaces, and impairs the concentricity of the planetary arrangement to the extent that slippage and wear occur.

Therefore, for a given high load, geometrical causes of wear should be eliminated as far as possible, while contact areas should be It is necessary to ensure accurate and constant lubrication of the

The general object of the present invention is to eliminate the drawbacks of the prior art and, in particular, to provide a device with reduced size and size, high power and torque transmission, long life and operational reliability. ,
The object of the present invention is to provide a transmission device having a continuously variable speed control function of the type mentioned at the beginning, which can be effectively applied to the field of automobile traction.

The present invention is a transmission device having a continuously variable speed control function of the type described above, but further comprising rolling contact with two corresponding bearing surfaces of each tapered planet wheel coaxially with the planet wheel support. This objective is achieved by a transmission whose main feature is that it includes a rotatable sun wheel in the form of a sleeve with two axially spaced bearing surfaces.

Because of this feature, each tapered planet wheel has two straight bearing surfaces, which significantly reduce the loads on the bearing as it supports a rotating tapered planet wheel. The bearings only bear the tilting torque resulting from the tangential forces in the drive contact portion of the planet wheels. These straight bearing surface sections ensure that the Hertzian contact pressure is kept within a range that guarantees an acceptable suspension life of the transmission.

According to the invention, two corresponding bearing surfaces between the sun ring sleeve and each tapered planet ring are located at the intersection between the axis of rotation of the tapered planet ring and the axis of rotation of the planet ring support. It is located on a common conical genera which generally converges towards.

In this way, the rolling contact between the tapered planet wheel and the sun wheel sleeve is kept kinematically correct and free of lubricant dissipation phenomena.

According to another aspect of the invention, a smaller truncated portion of a tapered planet wheel, a corresponding conical surface of a driven annular member, and a larger truncated portion of said tapered planet wheel. a device for pressing the adjustment ring together into pressure contact with the inner surface of the adjustment ring and regulating axial movement of the adjustment ring along the larger truncated portion of the tapered planetary ring; The device is formed by a hydraulically actuated device.

This feature allows the operating requirements to be adjusted as a function of the torque value to be transmitted and the rotational speed of the transmission, such as the transmission ratio between the drive shaft and the driven wheel, the tapered planetary wheel and the driven annular member and the adjustment, respectively. As far as fluctuations in the contact pressure with the annular member are concerned, automatic control of the transmission is simple and functional, since the transmission can be immediately adapted to the operating requirements, for example by means of an electronic control unit. Make it easier.

Another feature of the transmission according to the invention is that the components of the transmission can be self-centering in the loaded state, so that operational tolerances and any operational deviations arising from play in the assembly or that may occur in the loaded state are It is possible to eliminate the difficulty of
Continuous supply of liquid lubricant under pressure to the contact areas between the tapered planetary wheels and the respective adjustment ring, driven ring and sun wheel sleeve, as well as to the bearings supporting the rotating parts of the transmission during rotation. Possible lubricating device.

The invention will now be described with reference to the accompanying drawings. It should be understood that the drawings depict preferred embodiments of the invention by way of non-limiting illustration only.

Referring to FIGS. 1 and 2, a generally cylindrical housing 10 has a tubular projection 12 at one end and is closed at the other end by a plate 14. As shown in FIGS. A hollow support 16 is fixed to the inner surface of the plate 14 and has a tubular projection 18 coaxial with the tubular projection 12 at its inner end.

A hollow input shaft 20 extends through the housing 10 and is driven by the shaft of the motor vehicle engine.

The input shaft 20 is supported for rotation by a tubular projection on one side and by the tubular projection 18 on the other side by means of roller bearings indicated at 24 and 26, respectively.

A drive shaft 28 rotatably surrounds a central portion of the input shaft 20 in a coaxial relationship. An axially slidable disk 30 is connected to the end of the drive shaft 28 facing the tubular projection 12, which disk 30 displaces the drive shaft 28 during rotation.
is associated with a hydraulically actuated friction clutch 32 of known type for coupling and disengaging the input shaft 20 and the input shaft 20. The planetary wheel support 34 is formed from a rear disk 38 and a front disk 40, which are interconnected by partitions 42 which are equiangularly spaced relative to the drive shaft 28. In the area between the connecting bulkheads 42, the rear and front disks 38, 40 are provided with two sets of three mutually aligned radial notches 38a, 40a. The ends of the pins 44 are slightly engaged in each corresponding pair of notches 38a, 40a, and a rotatable planetary wheel 46 in the form of a tapered roller 46 is mounted on the pins.

As shown in detail in FIG.
, that is, they converge toward the rear of the housing 10 at a point C on the axis of rotation of the shafts 20, 28.

Each of the tapered planet wheels 46 is hollow to minimize centrifugal force effects during operation, and the large truncated portion 4
8, a smaller frusto-shaped portion 50 formed by an annular protrusion adjacent to the larger base of the frusto-shaped portion 48, and a cylindrical inner surface and a conical outer surface at the anterior 54 and posterior 52, respectively. and two tip portions. The larger truncated portion 48 converges toward the front of the housing, while the smaller truncated portion 50 and the conical surfaces of the tips 52, 54 converge toward the rear of the housing 10. match. More specifically, as shown in FIG. 3, the conical surfaces of the tips 52 and 54 converge in common toward the point C where the rotational axis of the tapered planetary wheel 40 is directed, as described above. match.

Each planetary ring 46 is rotatably mounted on each pin 44 by a pair of radial roller bearings between the inner surfaces of the tips 52, 54 and their corresponding portions of the pin 44.

The radially outer surfaces of the larger truncated portions 48 of the planetary wheels 46 are arranged in a common imaginary cylindrical surface that is concentric with the axis of rotation of the planetary wheel support 34.

The surfaces of these larger truncated portions 48 roll into contact with the inner surface of an adjustment ring 58 which is mounted for axial sliding but non-rotation relative to the housing 10. In fact, said adjusting annular member 58 is associated at its front face with diametrically opposed radial pins 60, on the outer ends of which are fitted two rollers 62, said rollers 62 engages an axial guide slot 64 formed in the side wall of the hollow cylindrical element 66. The cylindrical element 66 is connected with a radial gap to the side wall of the hollow body 16 by a pair of pins 68, the pins 68 being diametrically opposed to each other and the pins 60 It is angularly shifted by 90 degrees. In this way, the adjusting annular member 50 moves freely with respect to the three guiding stars 46, and is self-aligning.

For the reasons mentioned above, the axial movement of the adjusting annular member 58 is effected by a set of three hydro-hydraulic actuators 70 spaced an equal distance apart in the angular direction with respect to each other. The actuating devices 70 each include a cylinder 72 integrally formed with the hollow element 66, within which the rod 7 is inserted.
A piston 74 with 6 is slidable. Each rod 7
The outer end of 6 has a generally spherical surface, and this surface corresponds to the spherical surface 7 formed on the main rear surface of the adjustment annular member 58.
It abuts a shallow depression with 8. three axial return members 80 equally angularly spaced apart from each other but angularly offset relative to the hydraulic actuator 70;
acts on the opposite major surface of the annular member 58. Each of the return members 80 includes a socket element 82;
At the bottom of the socket element there is a projection with a generally spherical surface 86 which presses by means of a spiral spring 88 into a recess with a spherical surface 84 corresponding to said spherical surface of the annular member 58.

Small truncated portion 5 of three tapered planet wheels 46
0 abuts the corresponding conical inner surface 90 of the driven annular member 92. A ring 94 that rotates coaxially with the drive shaft 28 is integrally formed on the driven annular member S2. The two front wheels S4 are rotatably supported by the tubular protrusion 18 of the hollow support 16 by a tapered roller bearing 96, and a crown gear 98 of outer teeth is fitted therein. The crown gear 98 meshes with a cylindrical gear 100 provided on a driven wheel 102 parallel to the input shaft 20. The inner end of the driven shaft 102 is connected to a tubular projection 104 of a hollow support 16 in which a bearing 106 is located.
It is rotatably supported by. The outer end, on the other hand, passes through an opening in rear plate 14, which rotatably supports driven wheel 102 by means of a bearing 108 for transmitting drive power to other equipment on the vehicle.

Contact pressure between the smaller truncated portion 50 of the planetary wheel 46 and the driven annular member 92 and between the larger truncated portion 48 of the planetary wheel 46 and the inner surface of the adjustment annular member 58 is provided by a hydrodynamic actuator generally indicated at 112. This actuating device 112 is formed by an annular cup-shaped element 114 which is coaxial with the drive shaft 28 and whose cavity faces the front disk 40 of the planet wheel support 34 and which is supported in the housing 10. An annular piston 116 is mounted in the cavity of the element 114 for axial sealing sliding under the action of a spring wall 118 which urges the piston axially towards the planet wheel support 34. try to. The annular piston 116 has a hub 120 that partially surrounds the drive shaft 28 and has a sleeve 122 coaxial with the hub.
It is in contact with a rotatable solar ring in the form of . A radial ball bearing 124 and an axial bearing 126 are disposed between the hub 120 of the piston 116 and the sleeve 122 of the sun wheel. The axial bearing 126 is formed from two rings of straight rollers 128 located between an inner center plate 132, a first outer bearing block 132, and a second outer bearing block 134, respectively. . The blocks respectively include a hub 120 and a sun wheel sleeve 1.
It rests against the annular shoulder of 22. According to the modification shown in FIG. 4, bearings 96, 124, and 126 are preferably replaced by a pair of axially orientable roller bearings 150.

The sun wheel sleeve 122 has two outer bearing surfaces 136, 138 associated with its ends, which bearing surfaces are similar to the outer surfaces of the tips 52, 54 of the three tapered planet wheels 46. I fell into contact with him. The bearing surfaces 136 and 138 are conical surfaces, and the generatrix surfaces thereof coincide with the generatrix surfaces of the conical surfaces of the tips 52 and 54, so that they converge toward the aforementioned point C as shown in FIG. .

By making the solar wheel sleeve 122 into the above-described shape,
It significantly reduces the load on the bearings 56 of the tapered planet wheels 46, thereby significantly reducing the Hertzian pressure at the contact area with the planet wheels 46 and eliminating any dissipative phenomena.
e spin phenomena) can also be removed.

The operation of the transmission described above is epicyclic.

In fact, when the rotation of the input shaft 20 is transmitted via the friction clutch 32 to the drive shaft 28 and then to the planetary wheel support 34,
The rotation of the tapered planetary wheel 46 causes the larger truncated portion 48 to roll over the adjustment annular member 58;
The outer surfaces of the tip portions 52 , 54 roll over the sun wheel sleeve 122 and transfer motion to the driven annular member 92 and then to the driven wheel 102 .
Communicate to. The axial position of the adjusting annular member 58 determines whether the driven wheel 102 rotates in the same direction as the drive shaft 28, in the opposite direction, or not at all.

In fact, the planetary wheel support 34 is used as an input element and an annular adjustment member 9.
Considering 2 as the output element, the transmission described above provides a transmission ratio in the following range:

T=r/(r-1) r=RS1 RC2/RC1 RS2, RS1, RS
2, RC1, and RC2 are the radii shown in FIG.

When r is greater than 1, the driven shaft 102 rotates in the same direction as the drive shaft 28, and when r is less than 1, it rotates in the opposite direction. If r is equal to 1, the driven wheel is stationary.

The hydraulically actuated piston 116 operates such that the contact value between the tapered planetary ring 46 and the driven annular member 92 varies as a function of the torque value to be transmitted. The interference of the actuating device 112 can be controlled automatically, for example with the aid of an electronic control unit, so that overloads occurring at the contact points between the rotating parts of the transmission as a result of centrifugal forces can be compensated for.

In order to ensure that the transmission operates with kinematic precision and eliminates negative effects caused by operating tolerances, air gaps in the assembly and yields due to loads, the epicyclic motion according to the invention The transmission is completely self-centering. This self-aligning property is achieved by assembling the adjusting annular member 58 and the planetary ring 46 with the planetary ring support 34 as described above, and by assembling the adjusting annular member 58 and the driven annular member 92. This is made possible by making the mutual contact surfaces have a specific curvature. In fact, the bearing surfaces between the actuating devices 70 , 80 and the adjusting ring 58 and between the sun wheel sleeve 22 and the hub support bearing 120 and between the piston 116 of the hydrodynamic actuating device 112 and the cup-like element 1
The contact surfaces, such as the bearing surfaces, between 14 and 14 are slightly convex.

Furthermore, since the operation of the transmission is based on the elastohydraulic principle of the lubricant and takes advantage of the shear strength of the lubricant film between the rolling contact surfaces, it is entirely possible to achieve precise and constant lubrication. . The transmission according to the invention avoids even partial immersion of the rotating parts of the transmission in the lubricant, thereby eliminating increased losses due to dissipation of the lubricant, so that a large amount of the transmission is contained in the housing 10. To provide a special lubricating device that can always reliably supply lubricant to a contact part at an accurate pressure even under all operating conditions without having to keep lubricant in it. In particular, this lubricating device includes an inlet union 1 for lubricant connected to an annular pipe 144 by a telescoping pipe 142.
40, the pipe 144 is fixed to the front surface of the adjusting annular member 58, and has a plurality of holes in its wall through which lubricant is injected to the contact surface between the planetary ring 46 and the annular member 58. There is. The lubricant is supplied to the input shaft 2 by another inlet union 146.
0 into the cavity and then through a series of radial openings (not shown) in the wall of said input shaft 20.
6 and the driven annular member 92.

The same lubricant is used for both purposes to lubricate the bearings 124, 134 and as the working fluid for the hydraulic actuator 70 that moves the adjustment ring 58 and for the hydrodynamic actuator 112. In the latter case, the lubricant is introduced into the cavity of the cup-like element 114 by the inlet union 148.

[Brief explanation of the drawing]

FIG. 1 shows the transmission device according to the invention along the line I--I of FIG.
FIG. 2 is a cross-sectional view taken along line II-II of FIG. 1;
The figure is an illustrative view showing details of FIG. 1; and FIG. 4 is a detailed sectional view. In the figure, 10...Housing 14...Plate 28...
Drive shaft 34... Planet wheel supports 38a, 40a...
Slot 44... Pin 46... Planet wheel 48...
・Larger truncated portion 50...Small truncated portion 52, 54...Tip 56...Bearing 58.
... Annular member 62 ... Roller 64 ... Guide slot 66 ... Hollow element 68 ... Pin 70 ... Actuation device 76 ... Rod 90 ... Support surface 92 ... Driven annular member 102...driven wheel 112...
... Actuation device 116 ... Piston 120 ... Hub 122 ... Sun wheel sleeve 124, 126 ... Bearing 130 ... Central plate 132, 134 ... Bearing block 136, 13
8...Supporting surface 140...Inlet union 142...Pipe 144
...Plumbing agent Akira Asamura and 4 people

Claims (1)

[Claims] 1) A housing (10), a drive shaft (28) and a driven shaft (10) extending inside the housing.
2); a planetary wheel support (34) mounted within the housing to be rotated by the driveshaft; and a planetary wheel support (34) supported by the planetary wheel support for rotation by a bearing (56); angularly spaced relative to each other about the axis of rotation of the planetary ring support and adjacent the larger base of the larger frustum (46); ), the radially outer generatrix of said larger truncated portion extending generally parallel to the axis of rotation of said planetary wheel support. a planetary wheel (46); an adjusting annular member (58) that is locked against rotation with the housing and whose inner surface rolls into contact with the surface of the larger truncated portion of the tapered planetary wheel; a device for adjusting the axial movement of said adjusting annular member along a larger truncated portion of the planetary ring; a driven annular member (92) having a conical inner surface (90) corresponding to the surface of the smaller truncated portion and for rotating said driven wheel; and a smaller frustum of said tapered planetary wheel. a device for pressing the surface of the shaped portion, the corresponding conical surface of the driven annular member, the surface of the larger truncated portion of the tapered planetary ring, and the inner surface of the adjusting annular member together into pressure contact; A planetary transmission device equipped with a continuously variable speed control function. 2) A device according to claim 1, in which the two bearing surfaces (136, 138) of the solar sleeve (122)
) and the two corresponding bearing surfaces (52, 54) of each tapered planet wheel (46) at the axis of rotation of said planet wheel support (34). 1. A planetary transmission device characterized in that the rotational axes of the planetary transmission devices 1 and 2 are arranged on a common conical generatrix surface that substantially converges toward a point (C) where the rotational axes of the planetary gears 1 and 2 intersect. 3) In the device according to claim 1 or 2, the smaller truncated portion (50) of the tapered planetary ring (46) and the driven annular member (92) a corresponding conical surface (90), and said tapered planetary ring (
46), characterized in that the device for pressing the larger truncated portion (48) and the inner surface of the adjusting annular member (58) together into pressure contact includes a hydrodynamic actuator (112). Planetary transmission. 4) The device according to claim 3, wherein the planetary wheel support (34) and the sun wheel sleeve (122) are slidably mounted on the drive shaft (28), and the hydrodynamic actuation Planetary transmission, characterized in that a device (112) is operative to press said sun ring sleeve (122) axially towards a driven annular member (92). 5) A device according to claim 4, in which the hydrodynamic actuator (112) is arranged in coaxial relationship with the drive shaft (28) and at the larger truncated end of the tapered planetary wheel (46). an annular piston (116) facing the smaller base of the body portion (48), the piston (116) comprising:
Planetary transmission, characterized in that it has a central hub (120) in which a bearing is located and rotatably supports a sun wheel sleeve (122). 6) A device according to claim 5, wherein the bearing comprises a radial bearing (124) and an axial bearing (126), the axial bearing comprising a straight roller (126) with a central plate (130) in between.
128) and first and second bearing blocks (132, 134), the first bearing block being a hub (120) of a piston (116).
A planetary transmission, characterized in that the second bearing block abuts the sun ring sleeve (122). 7) In the device according to claim 5, the tapered planetary ring (46) is movable in the radial direction with respect to the planetary ring support (34), and the adjusting annular member (58) is tapered. It is supported by the housing (10) so as to be self-centering with respect to the planetary ring (46), and each of the tapered planetary ring (46), the adjusting annular member (58), and the driven annular member (92) and the contact portion between the solar wheel sleeve (122) and the sleeve (122).
) and the bearing between the piston (116) is a slightly convex surface. 8) In the device according to claim 7, each of the tapered planet wheels (46) has an axial cavity, through which the planet wheels are rotatably rotated by a pair of radial bearings (56). (46) is supported, and both ends are provided with corresponding notches (38a, 4) of the planetary wheel support (34).
0a) radially slidable to engage the pin (46
) is inserted into the planetary transmission device. 9) A device according to claim 7, fixed to the housing (10) by a pair of coaxial radial pins (68) and offset by 90 degrees with respect to said pins (68). diametrically opposed axial slots (
an inner tubular body (66) having an inner tubular body (64), in which two rollers (62) supported by a pair of corresponding radial pins (60) integral with the adjusting annular member (58) are guided; A planetary transmission device characterized by: 10) The device according to claim 1, in which the larger truncated portion (48) of the tapered planetary ring (46)
Planetary transmission, characterized in that the adjustment device for the axial movement of the adjustment annular member (58) along ) comprises a plurality of hydro-hydraulic actuation devices (70). 11) In the device according to claim 7 or 10, the hydrodynamic actuator (70) includes a rod (76) having a convex end surface that contacts the adjustment annular member (58).
) is provided. 12) In the device according to any one of claims 1 to 11, the tapered planetary ring (46)
and the adjustment annular member (58), the driven annular member (92), and the sun ring sleeve (122), as well as the tapered planet ring (46) and the planet ring support (3).
4) and to the bearings (56, 124, 126) between the sun wheel sleeve (122) and the piston (11G) of the hydrodynamic actuator (112), under pressure. A planetary transmission further comprising a lubricating device for supplying lubrication. 13) In the device according to claim 12,
The lubricating device is fitted into an inlet union (140) and a porous tubular pipe (1) fitted in a coaxial relationship with an annular adjusting member (58).
44) and a telescoping pipe (142) connecting the inlet union (140) to the porous tubular pipe. 14) In the device according to claim 12,
A planetary transmission device further comprising a supply device that supplies liquid lubricant to the hydrodynamic actuation device (70, 112) to operate it.