WO2019008122A1

WO2019008122A1 - Lubrication and/or cooling device for, and a continuously variable transmission system including such a lubrication and/or cooling device

Info

Publication number: WO2019008122A1
Application number: PCT/EP2018/068308
Authority: WO
Inventors: Kevin Ben VAN GAEVER
Original assignee: Punch Powertrain N.V.
Priority date: 2017-07-05
Filing date: 2018-07-05
Publication date: 2019-01-10
Also published as: BE1025361B1; BE1025361A9; CN111051740A; BE1025361B9; BE1025361A1; CN111051740B; DE112018003452T5

Abstract

A lubrication and/or cooling device (6) for and/or included in a belt or chain type continuously variable transmission system that includes a housing (11), a liquid supply source, and an endless transmission element (5) for transmitting power between a primary pulley (1) and a secondary pulley (2). The device (6) comprises an elongate fluid conducting pipe body (7) having a proximal end portion (8) having a fluid entry connectable to the liquid supply source and a distal end portion (9). The device also comprises at least a first and a second fluid discharge opening (21, 23), each located on the distal end portion of the fluid conducting pipe body (7). The elongate fluid conducting pipe body (7) includes a first fluid conducting channel (15) in fluid communication with the first fluid discharge opening (21), and second fluid conducting channel (17) separate from the first fluid conducting channel (15). The second fluid conducting channel (17) is in fluid communication with the second fluid discharge opening (23).

Description

Title: Lubrication and/or cooling device for, and a continuously variable transmission system including such a lubrication and/or cooling device

The invention relates to a lubrication and/or cooling device for a flexible member type continuously variable transmission (CVT) system that uses an endless metal belt for transmitting power between a primary pulley and a secondary pulley. Such a lubrication device can also be used for cooling of the flexible member or for lubrication and/or cooling of the flexible member.

As is usual in such flexible member type CVT's each of the primary and secondary pulleys includes an axially stationary conical sheave halve and an axially movable sheave halve. The flexible member can be a belt member or a chain member. The axially movable sheave halves of the primary and secondary pulleys are arranged to move in directions laterally opposite to one another. As a result the power transmitting belt or chain performs a lateral movement when the radius about the primary and secondary pulleys varies with the transmission ratio. For the efficiency of lubrication and/or cooling of the flexible transmission belt or chain and the pulley sheave halves, it is important that a liquid lubrication and/or cooling medium, such as oil, is distributed accurately to the critical locations and in a sufficient quantity. Several proposals have been used for spraying a hydraulic medium onto portions of an endless transmission element to achieve this objective, but none so far has been entirely satisfactory in the light of continuingly increasing power ranges and efficiency demands.

In known systems the hydraulic medium, such as oil, is sprayed by means of a liquid supply pipe that extends between the primary and secondary pulleys. Such systems are generally know from and described in patent documents EP 0 574 085 Bl; US 5,605,513, US 6,068,565; US

6,537,166 Bl; WO 98/20269; US 6,626,781 B2; and US 8,672,097 B2. A single liquid supply pipe can be used having two nozzles, or two separate pipes can be used each having a single nozzle resulting in more components in the transmission. The liquid supply pipe that extends between the primary and secondary pulleys is usually provided with at least two discharge openings formed as orifices or nozzles for spraying the pressurized fluid onto the area within which the laterally movable flexible member and sheave halves are bound to move. EP 0 894 535 discloses for example a single liquid supply having a single nozzle with two or more ejectors. Since one of the at least two discharge openings may be downstream of the other there is a loss of pressure in the fluid available at the downstream discharge opening with respect to the upstream discharge opening. This difference in pressure has a negative effect on the spray pattern of the downstream discharge opening, which can only be compensated by differentiating between the discharge opening sizes or nozzle configurations, in particular at a specific supply pressure. With the hitherto commonly used metal pipes this differentiation between the discharge openings would require

complicated manufacturing procedures and/or costly ancillaries.

Hence it is an object of the present invention to propose, and embodiments of the present invention seek to provide, an improved lubrication and/or cooling device for a flexible member type continuously variable transmission system. In a more general sense it is an object of the invention to overcome or reduce at least one of the disadvantages of the prior art. It is also an object of the present invention to provide alternative solutions which are less cumbersome in assembly and operation and which moreover can be made relatively inexpensively. Alternatively it is an object of the invention to at least offer a useful alternative.

To this end the invention provides a lubrication and/or cooling device for a flexible member type continuously variable transmission system, and a continuously variable transmission system, as defined by one or more of the appended claims. A lubrication and/or cooling device according to the invention is suitable for and can be included in a flexible member type continuously variable transmission system that includes a housing, a liquid supply source, and an endless transmission element for transmitting power between a primary pulley and a secondary pulley. The inventive device can comprise an elongate fluid conducting pipe body having a proximal end portion, a fluid entry connectable to the liquid supply source of a

continuously variable transmission system, and a distal end portion. The inventive device also comprises at least a first and a second fluid discharge opening, each of which is located on or adjacent to the distal end portion of the fluid conducting pipe body and are arranged to spray a lubrication and/or cooling liquid on said endless transmission element. The elongate fluid conducting pipe body can include a first fluid conducting channel in fluid communication with the first fluid discharge opening, and second fluid conducting channel separate from the first fluid conducting channel. The second fluid conducting channel can be in fluid communication with the second fluid discharge opening. The first and second fluid conducting channels preferably extend between the proximal end portion and the distal end portion of the pipe body. In the lubrication and/or cooling and/or cooling device according to the invention at least one of the first and second fluid discharge openings can be positioned to be directed transverse of the elongate fluid conducting pipe body. Alternatively or additionally the first fluid discharge opening can be positioned in-between the proximal and distal end portions, and the second fluid discharge opening is positioned adjacent the distal end portion. Both the first and second fluid discharge openings can also be positioned to be directed transverse of the elongate fluid conducting pipe body, and/or the second fluid discharge opening can be positioned in a transvers direction radially angled to the transverse direction of the first fluid discharge opening. The lubrication and/or cooling and/or cooling device is suitable for use with any type of flexible member that requires active lubrication and/or cooling.

Each of the first and second discharge openings of the device of the invention can be provided with a spray forming nozzle, and the spray forming nozzles of the first and second discharge openings may differ from one another.

In an embodiment of the device of the invention the fluid conducting pipe body can conveniently be formed as a casting. In the casing the first and second fluid conducting channels can be separated by a flat wall element that is incorporated in the casting forming the fluid conducting pipe body. The casting of the fluid conducting pipe body can further be made of a thermoplastic polymer. This thermoplastic polymer can be glass fiber reinforced, and/or can be a high temperature resistant grade of polymer. The fluid conducting pipe body of the device can appropriately be injection molded.

The lubrication and/or cooling and/or cooling device of the invention can also include one or more further fluid conducting channels and associated fluid discharge openings in addition to the first and second fluid conducting channels and fluid discharge openings. In this regard a cross- sectional area of one of the first and second discharge openings or of one of the first and second fluid conducting channels can be arranged to be different from the other. At least one of the first and second fluid conducting channels may also be associated with a flow regulating valve. Such a flow regulating valve can then be adapted to be actively controlled in dependency of the ratio of the continuously variable transmission system.

In a lubrication and/or cooling and/or cooling device of the invention the fluid conducting pipe body at its proximal end portion can have a fixation flange. A central longitudinal axis of the elongate fluid conducting pipe body can also be angled with respect to a mounting surface of the fixation flange. In a lubrication and/or cooling and/or cooling device of the invention the fluid entry can be positioned generally axially of the elongate fluid conducting pipe body.

A continuously variable transmission system according to the invention can include a primary pulley, a secondary pulley, an endless flexible member transmission element for transmitting power between the primary pulley and the secondary pulley, a housing, a liquid supply source, and the lubrication and/or cooling and/or cooling device having one or more of the above features. In this transmission system the lubrication and/or cooling and/or cooling device will be connected to the liquid supply source, while the liquid supply source will be arranged to supply a lubrication and/or cooling and/or cooling liquid to the first and second discharge openings of the fluid conducting pipe body. The proximal end portion of the lubrication and/or cooling device will be attached to the transmission housing, and the first and second fluid discharge openings will be arranged to spray the supplied lubrication and/or cooling liquid on the endless transmission element, in particular onto contacting surfaces of at least one of the endless transmission element and the primary and secondary pulleys. In such a continuously variable transmission system each of the primary and secondary pulleys can include an axially stationary conical sheave halve and an axially movable sheave halve. The axially movable sheave halves of the primary and secondary pulleys can then be arranged to move in directions laterally opposite to one another, and the power transmitting flexible member will thereby perform a lateral movement, when the radius about the primary and secondary pulleys varies with a transmission ratio resulting from controlled axial movement of the axially movable sheave halves of the primary and secondary pulleys. The transmission system can then further be arranged to have one of the first and second fluid discharge openings to spray a diverging jet of lubrication and/or cooling liquid in a flow direction towards a vicinity of the axially fixed primary sheave, and the other of the first and second fluid discharge openings to spray a diverging jet of lubrication and/or cooling liquid can be in a flow direction towards a vicinity of the axially fixed secondary sheave. The diverging jets can further be arranged to overlap in a central area coinciding with lateral belt or chain movement. The diverging jets of lubrication and/or cooling liquid can each also be directed in a direction of belt or chain movement, and/or the diverging jets can be differently angled.

The liquid supply source of the continuously variable transmission system of the invention can comprise at least one pump for supplying the lubrication and/or cooling liquid.

Further advantageous aspects of the invention will become clear from the appended description and in reference to the accompanying drawings, in which:

Figure 1 shows a detail of a detail of a continuously variable transmission system including the lubrication and/or cooling device of the invention;

Figure 2 is a front view of an embodiment of a lubrication and/or cooling device according to the invention;

Figure 3 is a cross section of the embodiment of Figure 2 along the line III - III;

Figure 4 is a transverse cross section of the embodiment of Figure 2 along the line IV - IV;

Figure 5 is a transverse cross section of the embodiment of Figure 2 along the line V - V;

Figures 6A to 6D schematically illustrate a selection of alternative transverse cross sections incorporating multiple channels;

Figure 7 is a variation with a four channel layout first valve member; and

Figure 8 is a second valve member for cooperation with the first valve member of Figure 7 to regulate the flow of lubrication fluid. A continuously variable transmission system of which a detail is shown in Figure 1 typically comprises a primary drive input pulley 1 driven by input shaft 2, and a secondary output pulley 3 driving an output shaft 4. Between the primary pulley 1 and the secondary pulley 3 extends a power transmitting endless flexible transmission element 5. In operation the endless transmission element 5 moves in the direction of arrow A. By altering the contact diameters of the primary and secondary pulleys the transmission ratio can be varied in a known manner. Because of the elevated contact pressure between opposite halves of the primary and secondary pulleys 1, 3 and the endless transmission element 5 it is necessary to continuously lubricate and cool these contact areas. To provide this lubrication and/or cooling a lubrication and/or cooling device 6 is located between the primary and secondary pulleys 1, 3. The lubrication and/or cooling device 6 sprays lubrication and/or cooling fluid in a direction B in- between the secondary pulley 3 and the endless transmission element 5. The lubrication and/or cooling device 6 also sprays lubrication and/or cooling fluid in a direction C in-between the primary pulley 1 and the endless transmission element 5.

The lubrication and/or cooling device 6 is shown in more detail in Figure 2 and comprises an elongate fluid conducting pipe body 7, which has a proximal end portion 8 and a distal end portion 9. The proximal end portion 8 is arranged for mounting to a transmission housing 11 (Figure 1) by means of a mounting or fixation flange 13. The mounting flange or fixation 13 as shown in Figure 3 is conveniently angled with respect to the elongate fluid conducting pipe body 9. The transmission housing 11 has an internal lubrication and/or cooling fluid supply, which can connect to each of a first fluid conducting channel 15 and a second fluid conducting channel 17, which channels 15, 17 extend between the proximal end portion 8 and the distal end portion 9. To assist in obtaining a fluid tight connection between the transmission housing 11 and the lubrication and/or cooling device 6 the proximate end portion 8 may also be provided with an O-ring receiving groove 19. Also positioned on the elongate fluid conducting pipe body 7 is a first fluid discharge opening 21, and a second fluid discharge opening 23. The first fluid discharge opening 21 is positioned in-between the proximal end portion 8 and the distal end portion 9 of the elongate fluid conducting pipe body 7. The second fluid discharge opening 23 is positioned directly adjacent to the distal end portion 9. The first and the second fluid discharge openings 21, 23 are arranged to spray a lubrication and/or cooling liquid on said endless transmission element. The first and second fluid conducting channels 15, 17, as shown in Figure 3 are separated by a wall element 25 that extends within a hollow interior of the fluid conducting pipe body 7 between the proximal end portion 8 and the distal end portion 9 in a longitudinal direction of the pipe body 7. As such, the pipe body 9 is a multichannel pipe body 9.

As shown in more detail in the cross sections of Figures 4 and 5 the mounting flange 13 is provided with an opening 27 for receiving a fastener, such as a bolt or screw. A reinforcing rib 29 may partially extend between the fluid conducting pipe body 7 and the mounting flange 13 for reinforcing the structural integrity of the lubrication and/or cooling device 6.

As is apparent from comparing the cross section of Figure 4 taken along the line IV - IV in Figure 2, and the cross section of Figure 5 taken along the line V - V in Figure 2, the first fluid discharge opening 21 extends in a direction that is substantially opposite to that of the second discharge opening 23. In the example of Figs. 2 to 5 the first and second fluid discharge openings 21, 23 are at an angle with respect to one another, but this arrangement may vary in accordance with the chosen mounting position on the transmission housing 11 and/or the required spray direction B, C between the first and second pulleys 1, 3 as the skilled person will understand. Also each of the first and second fluid discharge openings 21, 23 may be formed as a spray nozzle, or receive a separate spray nozzle, which may either be permanently or removably affixed to it. In order to easily and economically obtain the complex shape and the desired nozzle form or nozzle receiving structure of the lubrication and/or cooling device 6 the fluid conducting pipe body 7is best formed as a casting. Such a casting may be an injection moulding in either a zamac-alloy or of a thermoplastic polymer, such as a glass fibre reinforced high temperature resistant polymer grade.

While the above example has been described as providing separate first and second fluid conducting channels for discharging a lubrication and/or cooling fluid onto contacting surfaces of primary and secondary pulleys, it is conceivable that more than two a fluid conducting channels and fluid discharge openings are used. This may be useful to increase the coverage of the contact areas to be lubricated and cooled. As schematically shown in Figure 6 A the internal structure of the elongate fluid conducting pipe body 7 may in cross section be divided into first and second fluid conducting channels by a flat wall element 25, such as in the example of Figures 2 to 5. However as schematically shown in Figure 6B these first and second channels 15, 17 may also be formed with rounded contours to minimize flow resistance and/or to prevent deposits. As shown in Figures 6C and 6D in a similar schematic manner the cross section of the elongate fluid conducting pipe body 7 can also be subdivided in having additional third and fourth fluid conducting channels 29, 31, each extending between the proximal end portion 8 and the distal end portion 9.

Commensurate with the use of multiple fluid conducting channels in the lubrication and/or cooling device 6, the fluid supply from the transmission housing 11 may also be subdivided in separate supply channels having either the same or different supply sources within the transmission. In a further alternative arrangement schematically illustrated in Figures 7 and 8, the transmission housing 11 or the lubrication and/or cooling device 6 may additionally be provided with a fluid regulating valve. Such a fluid regulating valve may comprise a stationary first valve member 33 (Fig. 7), and a rotatable second valve member 35 (Fig. 8). The stationary first valve member 33 has a central pivot bearing 37 and apertures corresponding with the first, second, third and fourth fluid conducting channels 15, 17, 29, 31. The rotary second valve member 35 as shown in Figure 8 has opposite sectored wings 39, 41 opposite of a central pivot shaft 43. By rotating the second valve member 35 relative to the first valve member 33 in accordance with either arrow 45 or 47, the sectored wings 39, 41 will cover or uncover to a greater or lesser extend the apertures in the first valve member 33. Thereby the flow of lubricating and/or cooling fluid supplied from the transmission housing 11 to the lubrication and/or cooling device 6 may be varied in accordance with the transmission ratio and belt or chain position.

Accordingly there is described by way of example a lubrication and/or cooling device 6 for and/or included in a belt or chain type

continuously variable transmission system that includes a housing 11, a liquid supply source, and an endless flexible member transmission element 5, such as an endless metal belt or chain, for transmitting power between a primary pulley 1 and a secondary pulley 2. The device 6 comprises an elongate fluid conducting pipe body 7 having a proximal end portion 8 having a fluid entry connectable to the liquid supply source and a distal end portion 9. The device also comprises at least a first and a second fluid discharge opening 21, 23, each located on the distal end portion of the fluid conducting pipe body 7. The elongate fluid conducting pipe body 7 includes a first fluid conducting channel 15 in fluid communication with the first fluid discharge opening 21, and second fluid conducting channel 17 separate from the first fluid conducting channel 15. The second fluid conducting channel 17 is in fluid communication with the second fluid discharge opening 23.

It is thus believed that the operation and construction of the present invention will be apparent from the foregoing description and drawings appended thereto. Reference in this specification to any prior publication (or information derived from it), or to any matter which is known, is not, and should not be taken as, an acknowledgement or admission or any form of suggestion that that prior publication (or information derived from it) or known matter forms part of the common general knowledge in the field of endeavor to which this specification relates. For the purpose of clarity and a concise description features are described herein as part of the same or separate embodiments, however, it will be appreciated that the scope of the invention may include

embodiments having combinations of all or some of the features described. References to published material or sources of information contained in the text should not be construed as concession that this material or information was part of the common general knowledge in this country or abroad. Each document, reference or patent publication cited in this text should be read and considered by the reader as part of this text, and for reasons of conciseness the contents thereof is not repeated, duplicated or copied in this text. It will be clear to the skilled person that the invention is not limited to any embodiment herein described and that modifications are possible which may be considered within the scope of the appended claims. Also kinematic inversions are considered inherently disclosed and can be within the scope of the invention. In the claims, any reference signs shall not be construed as limiting the claim. The terms 'comprise', 'comprising' and 'including' when used in this description or the appended claims should not be construed in an exclusive or exhaustive sense but rather in an inclusive sense. Thus expression as 'including' or 'comprising' as used herein does not exclude the presence of other elements, integers, additional structure or additional acts or steps in addition to those listed. Furthermore, the words 'a' and 'an' shall not be construed as limited to Only one', but instead are used to mean 'at least one', and do not exclude a plurality. Features that are not specifically or explicitly described or claimed may additionally be included in the structure of the invention without departing from its scope. Expressions such as: "means for ..." should be read as: "component configured for ..." or "member constructed to ..." and should be construed to include equivalents for the structures disclosed. The use of expressions like: "critical",

"preferred", "especially preferred" etc. is not intended to limit the invention. To the extend that structure, material, or acts are considered to be essential they are inexpressively indicated as such. Additions, deletions, and modifications within the purview of the skilled person may generally be made without departing from the scope of the invention, as determined by the claims.

Claims

1. Lubrication and/or cooling device for a flexible member type continuously variable transmission system that includes an endless flexible member transmission element for transmitting power between a primary pulley and a secondary pulley, wherein the device comprises:

an elongated fluid conducting pipe body having a proximal end portion having a fluid entry connectable to a lubrication and/or cooling liquid supply source and a distal end portion; and at least a first and a second fluid discharge opening, each located on the distal end portion of the fluid conducting pipe body, arranged to spray a lubrication and/or cooling liquid on said endless transmission element; and

wherein the elongate fluid conducting pipe body includes a first fluid conducting channel in fluid communication with the first fluid discharge opening, and second fluid conducting channel separate from the first fluid conducting channel, which second fluid conducting channel is in fluid communication with the second fluid discharge opening.

2. Lubrication and/or cooling device as in claim 1, wherein at least one of the first and second fluid discharge openings is positioned to be directed transverse of the elongate fluid conducting pipe body.

3. Lubrication and/or cooling device as in claim 1 or 2, wherein the first fluid discharge opening is positioned in-between the proximal and distal end portions, and the second fluid discharge opening is positioned adjacent the distal end portion.

4. Lubrication and/or cooling device as in claim 2 or 3, wherein both the first and second fluid discharge openings are positioned to be directed transverse of the elongate fluid conducting pipe body.

5. Lubrication and/or cooling device as in claim 4, wherein the second fluid discharge opening is positioned in a transvers direction radially angled to the transverse direction of the first fluid discharge opening.

6. Lubrication and/or cooling device as in one of claims 1 to 5, wherein each of the first and second discharge openings is provided with a spray forming nozzle, and wherein the spray forming nozzles of the first and second discharge openings differ from one another.

7. Lubrication and/or cooling device as in one of claims 1 to 6, wherein the fluid conducting pipe body is formed as a casting.

8. Lubrication and/or cooling device as in one of claims 1 to 7, wherein the first and second fluid conducting channels are separated by a flat wall element that is incorporated in the casting forming the fluid conducting pipe body.

9. Lubrication and/or cooling device as in claim 7 or 8, further including one or more fluid conducting channels and associated fluid discharge openings in addition to the first and second fluid conducting channels and fluid discharge openings.

10. Lubrication and/or cooling device as in one of claims 7, 8 or 9, wherein a cross-sectional area of one of the first and second discharge openings or of one of the first and second fluid conducting channels is different from the other.

11. Lubrication and/or cooling device as in one of claims 7 to 10, wherein at least one of the first and second fluid conducting channels is associated with a flow regulating valve.

12. Lubrication and/or cooling device as in claim 11, wherein the flow regulating valve is adapted to be actively controlled in dependency of the ratio of the continuously variable transmission system.

13. Lubrication and/or cooling device as in one of claims 1 to 12, wherein the casting of the fluid conducting pipe body is made of a

thermoplastic polymer.

14. Lubrication and/or cooling device as in claim 13, wherein the thermoplastic polymer is glass fiber reinforced.

15. Lubrication and/or cooling device as in one of claims 13 or 14, wherein the thermoplastic polymer is a high temperature resistant grade of polymer.

16. Lubrication and/or cooling device as in one of claims 1 to 15, wherein the casting of the fluid conducting pipe body is injection molded.

17. Lubrication and/or cooling device as in one of claims 1 to 16, wherein the fluid conducting pipe body at its proximal end portion has a fixation flange.

18. Lubrication and/or cooling device as in claim 17, wherein a central longitudinal axis of the elongate fluid conducting pipe body is angled with respect to a mounting surface of the fixation flange.

19. Lubrication and/or cooling device as in one of claims 1 to 18, wherein the fluid entry is positioned axially of the elongate fluid conducting pipe body.

20. Continuously variable transmission system including a primary pulley, a secondary pulley, an endless transmission element for

transmitting power between the primary pulley and the secondary pulley, a housing, a liquid supply source, and the lubrication and/or cooling device of one of the preceding claims 1 to 19 connected to the liquid supply source, wherein the liquid supply source is arranged to supply a lubrication and/or cooling liquid to the first and second discharge openings of the fluid conducting pipe body, wherein the proximal end portion is attached to the housing, and wherein the first and second fluid discharge openings are arranged to spray the supplied lubrication and/or cooling liquid onto contacting surfaces of at least one of the endless transmission element and the primary and secondary pulleys.

21. Continuously variable transmission system as in claim 20, wherein each of the primary and secondary pulleys includes an axially stationary conical sheave halve and an axially movable sheave halve, wherein the axially movable sheave halves of the primary and secondary pulleys are arranged to move in directions laterally opposite to one another, and wherein the power transmitting belt or chain performs a lateral movement when the radius about the primary and secondary pulleys varies with a transmission ratio resulting from controlled axial movement of the axially movable sheave halves of the primary and secondary pulleys, further arranged to have one of the first and second fluid discharge openings to spray a diverging jet of lubrication and/or cooling liquid in a flow direction towards a vicinity of the axially fixed primary sheave, and the other of the first and second fluid discharge openings to spray a diverging jet of lubrication and/or cooling liquid in a flow direction towards a vicinity of the axially fixed secondary sheave, the diverging jets are further arranged to overlap in a central area coinciding with lateral belt or chain movement.

22. Continuously variable transmission system as in claim 21, wherein the diverging jets of lubrication and/or cooling liquid are each directed in a direction of belt or chain movement.

23. Continuously variable transmission system as in claim 21 or 22, wherein the diverging jets are differently angled.

24. Continuously variable transmission system as in one of claims 20 to 23, wherein the liquid supply source comprises at least one pump.