TW201923217A - Pneumatically adjustable CVT - Google Patents

Abstract

For a CVT, comprising a cone pulley pair (2) having at least one axially movable cone pulley (21), an actuating device (5) for adjusting a position of the axially movable cone pulley (21) and a control unit (6), which is designed to actuate the actuating device (5) in order to change the position of the axially movable cone pulley (21), wherein the actuating device (5) comprises a pneumatic chamber (50), which is arranged on a rear side (22) of the axially movable cone pulley (21), with the result that a change in a pressure in the pneumatic chamber (50) causes an axial movement of the axially movable cone pulley (21) in the axial direction (X-X), wherein the axially movable cone pulley (21) is arranged on an outer sleeve (54), wherein the outer sleeve (54) is arranged on a crankshaft (11) in such a way that it can be moved in the axial direction (X-X), the proposal is that at least one axial slot (62) extending in the axial direction (X-X) is formed in an inner wall (61) of the outer sleeve (54).

Description

   Pneumatic adjustable continuous transmission   

The present invention relates to a pneumatically adjustable continuously variable transmission (CVT) for small vehicles such as two-wheelers, tricycles, four-wheelers, or snowmobiles, and to an internal combustion engine and A vehicle. The invention relates to a pneumatically adjustable CVT, which has the characteristics of a pre-characterized clause as in independent claim 1.

In various embodiments, CVTs are known in the prior art. In a vehicle, a continuously variable transmission enables a suitable transmission ratio to be achieved in each case compared to a transmission with fixed gears. A specific area of application for such CVTs is in small vehicles such as two-wheeled vehicles, tricycles ("tuk-tuk", snowmobiles, four-wheeled vehicles or small locomotives). In this type of CVT, centrifugal type is often used The governor adjusts the position of the tapered pulley on the belt. Depending on the rotation speed, the centrifugal weight of the centrifugal governor is offset from its radial position, thereby changing the axial distance between the two tapered pulleys. And thereby change the transmission ratio. However, one disadvantage of these configurations is that there is no possibility to intervene in the transmission ratio of the CVT through open-loop or closed-loop control. In this context, it will be necessary to be able to The simple approach used on small vehicles intervenes in the CVT's transmission ratio through open-loop or closed-loop control.

DE 10 2015 214 153 A1 shows a CVT with a pneumatic actuating device which adjusts an axially movable conical pulley by means of aerodynamic forces. To this end, an actuating device is provided for the purpose of adjusting the position of the conical pulley that can be moved axially. The actuating device is a pneumatic actuating device, which adjusts a conical pulley that can be moved axially by means of aerodynamic force. The actuation device comprises a pneumatic chamber which is arranged on the rear side of an axially movable conical pulley. Here, the rear side of the tapered pulley that is axially movable is the side that is not in contact with the surrounding member of the CVT. Therefore, changing the pressure in the pneumatic chamber causes an axial movement of the tapered pulley. Here, the pressure is counteracted or increased by the force attributed to the centrifugal element.

The present invention proposes a CVT. The CVT includes: a pair of tapered pulleys having at least one tapered pulley that can be moved axially; an unifying device for adjusting a position of the tapered pulley that can be moved axially; and a control unit , Which is designed to actuate the actuating device so as to change the position of the axially movable conical pulley, wherein the actuating device includes a pneumatic chamber configured in the axially movable On a rear side of the tapered pulley, the result is that a change in pressure in the pneumatic chamber causes an axial movement of the axially movable tapered pulley in the axial direction, wherein the axially movable The moving conical pulley is disposed on an outer sleeve, wherein the outer sleeve is disposed on a crank shaft in a manner that allows the outer sleeve to move in the axial direction. According to the invention, at least one axial groove extending in the axial direction is formed in an inner wall of the outer sleeve.

Advantages of the invention

Compared with the prior art, the CVT according to the present invention having the features as claimed in claim 1 has the advantage that, with the axial groove extending axially, the outer sleeve not only acts as a spacer, but also serves for the axially A guide for the moving conical pulley and now enables the medium (more specifically the air) to be transferred in an axial direction into the pneumatic chamber via the slot in the inner wall of the outer sleeve. Thus, the pneumatic chambers can be connected pneumatically via the grooves in the inner wall of the outer sleeve in an advantageous good and simple manner. The air delivered to or from the pneumatic chamber can thus advantageously pass through a channel between the outer sleeve and the crankshaft, which channel is formed by the groove in the inner wall of the outer sleeve.

With the features indicated in the scope of the attached patent application, further advantageous embodiments and developments of the invention are possible.

In a particularly advantageous illustrative embodiment, the axially movable conical pulley is fixed to the outer sleeve, wherein the outer sleeve is arranged on an inner sleeve in such a way that the outer sleeve Can move in this axial direction. Thus, the outer sleeve can be moved on the inner sleeve in an advantageous and simple manner. At the same time, a medium (more specifically, air) for the pneumatic chamber can be provided in a favorable manner through a channel extending in the axial direction between the outer sleeve and the inner sleeve (the channel is borrowed Is formed by the axial groove in the inner wall of the outer sleeve), and can be advantageously connected to a pneumatic connection at the other end of the outer sleeve to regulate the pressure in the pneumatic chamber.

The inner wall of the outer sleeve is advantageously rested at least partly on the inner sleeve, wherein a channel extending in the axial direction is formed by the axial groove, wherein the channel is formed in the radial direction by The inner sleeve is delimited by the outer sleeve. The outer sleeve is thus guided on the inner sleeve in an advantageous good and stable manner and is movable in the axial direction. At the same time, a sealed channel is thus formed which extends in this axial direction. The channel may advantageously lead to the pneumatic chamber and is pneumatically connected to a rotary joint, for example at its other end.

In a particularly advantageous illustrative embodiment, the axial groove extends from a first end of the outer sleeve to a second end of the outer sleeve, wherein the first end of the outer sleeve faces the pneumatic chamber And the second end of the outer sleeve faces away from the pneumatic chamber. The medium (air in detail) is thus guided in the axial groove over the entire length of the outer sleeve in an advantageous manner. The first end of the outer sleeve is configured on the pneumatic chamber in a manner or connected to the pneumatic chamber in a manner such that the axial groove leads to the pneumatic chamber and therefore the pneumatic chamber The medium pressure can be adjusted by means of a medium (more specifically, air), and is supplied or discharged through the axial groove. The second end of the outer sleeve is arranged on a rotary joint, for example, in such a way that the axial groove leads to the rotary joint and is therefore pneumatically connected to the rotary joint. By changing the pressure at the rotary joint, it is therefore possible to change the pressure in the pneumatic chamber.

According to an advantageous illustrative embodiment, it is envisaged that at least one radial channel is arranged on the outer sleeve, wherein the radial channel extends at least partly in the radial direction and adjoins the axial groove. By means of such a radial channel, the medium (air in detail) in the axial groove (for example at the first end and / or the second end of the outer sleeve) can be in a radial direction Taken from the outer sleeve and in a component (e.g., a pneumatic chamber) configured around the outer sleeve (e.g., in the first end of the outer sleeve) and / or in a rotary joint (e.g., in the Into the second end of the outer sleeve).

According to an advantageous illustrative embodiment, it is envisaged that the radial channel is designed as a radial groove, wherein the radial groove is formed at the first end of the outer sleeve and / or the second end of the outer sleeve Office. A radial groove can adjoin the axial groove and be pneumatically connected to it in an advantageous simple manner and is advantageously easy to produce.

According to an advantageous illustrative embodiment, it is envisaged that the radial channel is designed as a radial opening, wherein the radial opening extends through the outer sleeve in the radial direction starting from the inner wall of the outer sleeve. A radial opening can adjoin the axial groove and be pneumatically connected to it in an advantageous good and simple manner and is advantageously easy to produce, such as, for example, drilling.

According to an advantageous illustrative embodiment, it is envisaged that the axial groove has a semi-circular, rectangular or triangular cross section.

Furthermore, the invention relates to an internal combustion engine comprising a CVT according to the invention. For example, an internal combustion engine includes, for example, at least one cylinder and an inlet pipe leading to the cylinder, wherein the inlet pipe is connected to the pneumatic actuating device of the CVT to provide aerodynamic power for adjusting the CVT. In this case, the inlet pipe can be connected to the pneumatic chamber. By using an inlet pipe, it is possible to use vacuum for pneumatically adjusting the CVT. This situation is particularly advantageous because the use of an internal combustion engine with an inlet pipe can obtain a vacuum in any case and the vacuum can additionally be used to adjust the transmission ratio of the CVT.

Furthermore, the invention relates to a vehicle comprising a CVT according to the invention and / or an internal combustion engine according to the invention.

The vehicle is preferably a small vehicle, specifically a two-wheeled vehicle or a three-wheeled vehicle or a four-wheeled vehicle or a snowmobile or a scooter or the like.

Illustrative embodiments of the invention are shown in the drawings and explained in more detail in the following description. In the drawings: FIG. 1 shows a schematic illustration of a CVT for a small vehicle according to a first illustrative embodiment of the present invention, and FIG. 2 shows a schematic section of a main drive through the CVT in FIG. 1, Fig. 3 shows an illustration of an illustrative embodiment of the outer sleeve of the CVT in Figs. 1 and 2; Fig. 4 shows an illustration of an illustrative embodiment of the outer sleeve of the CVT in Fig. 3; An illustration of an illustrative embodiment of an outer sleeve of a CVT and a crankshaft, FIG. 6 shows an illustration of an illustrative embodiment of an outer sleeve having the CVT from the inner sleeve of FIG. 5 and a crankshaft, and FIG. 7 shows an example of a CVT Description of an illustrative embodiment of an outer sleeve, FIG. 8 shows a schematic illustration of an actuation valve of a first illustrative embodiment, and FIG. 9 shows a schematic illustration of an actuation valve according to a second illustrative embodiment of the invention .

The CVT 1 according to a preferred illustrative embodiment of the present invention, that is, an adjustable continuous stepless transmission is described in detail below with reference to FIGS. 1 to 9.

As can be seen from FIG. 1, the CVT 1 includes a first driving tapered pulley pair 2 having a fixed tapered pulley 20 and an axially movable tapered pulley 21. A second tapered pulley pair is provided as the output element 13. The two tapered pulley pairs are connected to each other in a known manner by means of a surrounding member 12 (more specifically a drive belt).

The first tapered pulley pair 2 is disposed on a crank shaft 11 of the internal combustion engine 10. Here, the crank shaft 11 is connected to a fixed tapered pulley 20.

The CVT 1 further comprises a centrifugal element 3 which is arranged on a conical pulley 21 which can be moved axially. In this illustrative embodiment, the centrifugal element 3 is a ball. In this illustrative embodiment, for example, six centrifugal elements 3 are provided. However, of course, any number of centrifugal elements 3 may be provided. As an alternative, it is also possible to use a solid or air cylinder or the like. In this configuration, the centrifugal element 3 is disposed on the rear side 22 of the conical pulley 21 that is axially movable. The centrifugal weight 3 moves according to the rotation speed of the conical pulley, and therefore requires only fine adjustment of the transmission ratio by means of a pneumatic actuating device.

As can also be seen from FIG. 1, the inlet pipe 9 of the internal combustion engine 10 is connected to the vacuum reservoir 7 through a first line 16. Here, the check valve 18 is disposed in the first line 16. The second line 17 is provided as a line for feeding the main pressure in the vacuum reservoir 7 to the pneumatic chamber 50. The actuation valve 8 is arranged in the second line 17. The actuation valve 8 is shown in detail in FIGS. 8 and 9. The actuation valve 8 is actuated by means of a control unit 6 according to the desired transmission ratio of the CVT 1. The control unit 6 is designed to actuate the actuating device 5 in order to change the position of the conical pulley 21 which can be moved axially.

It is therefore possible to adopt the fact that the vacuum existing in the inlet pipe 9 of the internal combustion engine 10 is used as aerodynamic energy to adjust the transmission ratio of the CVT 1. Here, the pressure level in the inlet pipe 9 depends on the position of the throttle valve and the speed of the internal combustion engine. During operation of the internal combustion engine, a continuous vacuum supply to the vacuum reservoir 7 can thus be ensured. The axially movable conical pulley 21 is thereby achieved by means of a simple and reliable adjustment of the aerodynamic force. The return action can be achieved by means of environmental pressure. For example, the vacuum reservoir 7 may be disposed in a cavity in the carrier.

In the first illustrative embodiment described, the actuating device 5 is further arranged on the main side of the CVT, that is, on the input side. As an alternative, it is also possible for the actuation device to be arranged on the secondary side of the CVT, ie at the drive element 13. As a further alternative, the actuation means are arranged on the primary side and the secondary side.

In order to adjust the axial position of the conical pulley 21 that can be moved axially, a pneumatic actuating device 5 is now provided (Fig. 2). The actuating device 5 comprises a pneumatic chamber 50 which is arranged on the rear side 22 of a conical pulley which can be moved axially. The actuating device 5 is used to adjust the axial position of the conical pulley 21 that can be moved axially.

The actuation device 5 contains a pneumatic chamber 50. An illustrative embodiment of a pneumatic chamber 50 is shown in FIG. 2 in a schematic section of a conical pulley pair 2 passing through the CVT 1. The tapered pulley pair 2 includes a fixed tapered pulley 20 and an axially movable tapered pulley 21. The pneumatic chamber 50 is disposed on the rear side 22 of the tapered pulley 21 that is axially movable. The pneumatic chamber 50 is thus delimited by the rear side 22 of the conical pulley 21 that can be moved axially. The pneumatic chamber 50 is further delimited by the front side 31 of the pulley housing 30.

In this illustrative embodiment, a cylindrical housing wall 33 is formed on the pulley housing 30. In this illustrative embodiment, a cylindrical pulley wall 23 is formed on a tapered pulley 21 that is axially movable. The cylindrical pulley wall 23 is disposed in the overlap region 24 within the housing wall 33. The cylindrical pulley wall 23 of the tapered pulley 21 that is axially movable and the housing wall 33 of the pulley housing 30 are movable relative to each other in the axial direction X-X. When the axially movable conical pulley 21 is moved relative to the pulley housing 30 in the axial direction X-X, the size of the overlap region 24 changes. In this illustrative embodiment, the pulley wall 23 and the housing wall 33 delimit the aerodynamic chamber 50 in the radial direction R-R with respect to the outer zone. The sealing element 53 is arranged in an overlap region 24 between the pulley wall 23 and the housing wall 33. In this initial example, the sealing element 53 extends in a ring shape around the pulley wall 23, with the result that the pulley wall 23 is always closed in the radial direction with respect to the housing wall 33, and a sealed pneumatic chamber 50 is thus formed. The sealing element 53 is in constant contact with the pulley wall 23 and the pulley wall 23 is in constant contact with the housing wall 33. For example, the sealing element may be an O-ring, a shaft seal ring, a piston seal ring, or the like.

During CVT operation, the pulley housing 30 rotates along with the axially movable conical pulley 21. In this configuration, the axially movable conical pulley 21 is fixed to the outer sleeve 54 which is arranged on the inner sleeve 55 in such a way that the outer sleeve can be axially oriented Move up on XX. The crank shaft 11, the pulley housing 30, the axially movable conical pulley 21 and the fixed conical pulley 20 therefore rotate at the same speed.

The pulley housing 30 is, for example, indirectly or directly connected to the crank shaft 11, into which a sealing element (not shown in the figure) extending all the way around the crank shaft 11 is inserted. Here, the crank shaft 11 passes through a pulley housing 30 and a tapered pulley 21 that can be moved axially.

By changing the pressure in the pneumatic chamber 50, the position of the tapered pulley 21 with respect to the axial direction X-X can be changed. For example, when the actuating valve 8 connected the vacuum reservoir 7 to the pneumatic chamber 50 at that time, the pressure in the pneumatic chamber 50 was reduced, and as a result, the conical pulley 21 that could move axially was in the direction of arrow A Move axially. During this process, the axially movable conical pulley 21 moves within the pulley housing 30. Although the pulley housing is configured in a rotatable manner, it is still configured in a manner that prevents it from being axially oriented. Move up on XX.

Therefore, the distance between the axially movable conical pulley 21 and the fixed conical pulley 20 becomes larger, with the result that the transmission belt is further moved toward the crank shaft 11.

In order to change the pressure in the pneumatic chamber 50, a channel 63 extending in the axial direction X-X is formed between the outer sleeve 54 and the inner sleeve 55. The channel extends from the first end 56 of the outer sleeve 54 to the second end 57 of the outer sleeve. The first end 56 of the outer sleeve 54 faces the pneumatic chamber 50. The second end 57 of the outer sleeve 54 faces away from the pneumatic chamber 50. For example, the first end 56 of the outer sleeve 54 may be disposed in the pneumatic chamber 50. For example, the second end 57 of the outer sleeve 54 may be configured in a rotary joint. A channel 63 extending in the axial direction X-X leads to the pneumatic chamber 50 at the first end 56 of the outer sleeve 54 and to a rotary joint at the second end 57 of the outer sleeve 54. Thus, for example, air may be transferred from the rotary joint into the pneumatic chamber 50 via the passage 63. The swivel joint may be pneumatically connected to the pneumatic chamber 50 through a passage 63. The pressure in the pneumatic chamber 50 can be adjusted via the passage 63. The second line 17 can be arranged on the rotary joint, for example, in such a way that the second line 17 leads to the rotary joint. The second line 17 is therefore pneumatically connected to the pneumatic chamber 50 via a rotary joint and a passage 63 in the outer sleeve 54.

It is possible to provide one channel 63 or a plurality of channels 63. In this illustrative embodiment, four channels 63 are provided. The channels are formed by axial grooves 62 extending in the inner wall 61 of the outer sleeve 54 in the axial direction XX. This situation is illustrated in FIGS. 3 and 4. FIG. 3 shows a cross section through an illustrative embodiment of an outer sleeve 54 having four axial slots 64 formed in an inner wall 61 of the outer sleeve 54. FIG. 4 shows a side view of the outer sleeve 54. In this illustrative embodiment of the outer sleeve 54, a radial channel 64 is formed at the first end 56 and the second end 57 of the outer sleeve 54. In this illustrative embodiment, the radial channel 54 is designed as a radial groove 64.

5 and 6 show an illustrative embodiment of the outer sleeve 54 and the inner sleeve 55 and the crank shaft 11 from FIGS. 4 and 5. In this configuration, the inner wall 61 of the outer sleeve 54 rests partly on the inner sleeve 55. In a region in which the axial groove 62 is formed in the inner wall 61 of the outer sleeve 54, the inner wall 61 of the outer sleeve 64 does not rest on the inner sleeve 55. A passage 63 extending in the axial direction XX is formed by an axial groove 62. In this case, the channel 63 is delimited in the radial direction RR by the inner sleeve 55 and by the outer sleeve 54. In this configuration, the axial groove 62 extends from the first end 56 of the outer sleeve 54 to the second end 57 of the outer sleeve. Via the radial channel 54, the medium (more specifically, air) is taken away from the inner sleeve 55 by the channel 63 in the radial direction RR. In this illustrative embodiment, the radial channel 64 is designed as a radial groove 65, wherein the radial groove 65 is formed at the first end 56 of the outer sleeve 54 and the second end 57 of the outer sleeve 54. However, it is also possible that there are no radial channels 64 here, for example or alternatively, one or more radial channels 64 are provided, for example, only at one end of the outer sleeve 54. The radial channel can also be designed as a radial opening, for example as a bore through the outer sleeve 54 in the radial direction RR starting from the inner wall 61 of the outer sleeve 54.

The axial grooves 62 and the radial grooves 65 may have different cross sections, for example it is possible for the grooves to have a semi-circular, rectangular or triangular cross section. The axial grooves 62 and the radial grooves 65 may be produced, for example, in a sintering process or alternatively by machining.

FIG. 8 shows an illustrative embodiment of the actuation valve 8. In this illustrative embodiment, the actuating valve 8 is a 3 / 3-way valve, where the actuating valve 8 can establish a connection to the vacuum reservoir 7 on the one hand, and to the environment 19 (ambient pressure) on the other hand connection. The third position is the closed position of the actuation valve 8, which is shown in FIG. 5.

The distance between the axially movable conical pulley 21 and the fixed conical pulley 20 can then be reduced again by simply opening the actuation valve 8 to establish a connection to the environment 19.

FIG. 9 shows an alternative embodiment of the actuating valve 8, which in this illustrative embodiment comprises two 2 / 2-way valves 80, 81. In this configuration, one of the two 2 / 2-way valves is disposed between the vacuum reservoir 7 and the pneumatic chamber 50 and the other of the two 2 / 2-way valves is disposed between the pneumatic chamber 50 and Environment 19.

The invention is used in particular on small vehicles such as two-wheeled or three-wheeled vehicles or four-wheeled vehicles or snowmobiles or the like.

Of course, other illustrative embodiments and hybrid forms of the illustrated illustrative embodiments are also possible.

Claims (10)

A continuous variable speed transmission (CVT) includes a pair of conical pulleys (2) having at least one conical pulley (21) that can be moved axially; a concerted motion device (5) for adjusting the adjustable A position of the axially moving conical pulley (21), and a control unit (6) designed to actuate the actuating device (5) to change the axially movable conical pulley (21) In this position, wherein the actuating device (5) includes a pneumatic chamber (50), which is arranged on a rear side (22) of the axially movable conical pulley (21), as a result, the A change in pressure in one of the pneumatic chambers (50) causes an axial movement of the axially movable cone pulley (21) in the axial direction (XX), wherein the axially movable cone The pulley (21) is arranged on an outer sleeve (54), wherein the outer sleeve (54) is arranged on a crank shaft (11) in a way that makes the outer sleeve (54) accessible Moving in the axial direction (XX), characterized in that at least one axial groove (62) extending in the axial direction (XX) is formed in an inner wall (61) of the outer sleeve (54) .     The CVT according to item 1 of the patent application, wherein the axially movable conical pulley (21) is fixed to the outer sleeve (54), and the outer sleeve (54) is The mode is arranged on an inner sleeve (55), which allows the outer sleeve (54) to move in the axial direction (XX).         The CVT according to item 2 of the patent application, wherein the inner wall (61) of the outer sleeve (54) rests at least partly on the inner sleeve (55), and in the axial direction (XX A channel (63) extending above is formed by the axial groove (62), wherein the channel (63) passes through the inner sleeve (55) in the radial direction (RR) and through the outer The casing (54) is delimited.         The CVT according to any one of claims 1 to 3 of the patent application scope claim, wherein the axial groove (62) extends from a first end (56) of one of the outer sleeves (54) to the outer sleeve (54) a second end (57), wherein the first end (56) of the outer sleeve (54) faces the pneumatic chamber (50), and the second end of the outer sleeve (54) (57) Back to the pneumatic chamber (50).         The CVT according to any one of claims 1 to 4 of the scope of patent application, wherein at least one radial channel (64) is formed on the outer sleeve (54), wherein the radial channel (64) is at least partially Extending in the radial direction (RR) and adjoining the axial groove (62).         The CVT as described in claim 5 of the patent application scope, wherein the radial channel (64) is designed as a radial groove (65), wherein the radial groove (65) is formed in the outer sleeve (54). At the first end (56) and / or at the second end (57) of the outer sleeve (54).         The CVT as described in claim 5 of the patent application scope, wherein the radial channel (64) is designed as a radial opening, wherein the radial opening starts from the inner wall (61) of the outer sleeve (54) at The radial direction (RR) extends through the outer sleeve (54).         The CVT according to any one of claims 1 to 7 of the scope of patent application, wherein the axial groove (62) has a semi-circular, rectangular or triangular cross section.         An internal combustion engine comprising a CVT according to any one of claims 1 to 8 of the scope of patent application.         A vehicle includes a CVT as described in any one of claims 1 to 8 of the scope of patent application and / or an internal combustion engine as described in claim 9 of the scope of patent application.