JP5055324B2 - Belt type continuously variable transmission - Google Patents

Description

  The present invention relates to a belt-type continuously variable transmission, and more particularly to a lubricating structure for a belt.

  A belt-type continuously variable transmission (hereinafter referred to as “CVT”) has a continuously variable transmission ratio by changing the groove width of each pulley by winding a belt between a primary pulley and a secondary pulley having variable groove widths. Can be changed. In such a CVT, since the belt temperature rises due to friction between the belt and the pulley, it is necessary to supply lubricating oil to the belt and cool the belt so that the belt temperature does not rise excessively.

  Regarding cooling of the belt, Patent Document 1 provides nozzles for supplying lubricating oil to the belt on the primary pulley side and the secondary pulley side, respectively, and increases the supply amount of lubricating oil from the nozzle on the primary pulley side as the gear ratio increases. Is disclosed.

  Patent Document 2 discloses a configuration in which a nozzle that supplies lubricating oil to a belt application start position of a pulley and a nozzle that supplies lubricating oil to a belt application end position are provided.

JP-A-8-254260 JP 2003-214512 A

  When cooling the belt by supplying the lubricating oil to the belt, it is effective to supply the lubricating oil to a portion where the heat generation amount of the belt increases.

  According to the analysis on the heat generation amount of the belt conducted by the applicant (FIGS. 3A and 3B), it is found that the heat generation amount at the belt winding start position and the heat generation amount at the belt winding end position change according to the gear ratio. However, the techniques disclosed in Patent Documents 1 and 2 do not consider this point, and there is still room for improvement.

  The present invention has been made in view of such technical problems, and an object of the present invention is to optimize the supply of lubricating oil to the belt, reduce the amount of lubricating oil, and reduce the driving loss of the oil pump.

According to an aspect of the present invention, the transmission ratio is steplessly changed by hanging a belt between the primary pulley on the input side and the secondary pulley on the output side, and changing the groove width of the primary pulley and the secondary pulley. A belt type continuously variable transmission that includes a first oil supply nozzle that supplies lubricating oil to a belt winding start position of at least one of the primary pulley and the secondary pulley, and the belt winding end of the one pulley. includes a second oil supply nozzle for supplying a lubricating oil to the position, the oil supply allocation changing means for changing the quantity of oil from the second oil supply nozzles and the oil supply amount from the first fueling nozzle according to the gear ratio, the said One pulley is the secondary pulley, and the oil supply distribution changing means is configured such that the first oil supply amount with respect to the oil supply amount from the second oil supply nozzle decreases as the gear ratio decreases. The ratio of the quantity of oil from the oil nozzle is increased, the belt type continuously variable transmission is provided, characterized in that.
Further, according to another aspect of the present invention, a transmission ratio is reduced by wrapping a belt between the input-side primary pulley and the output-side secondary pulley and changing the groove width between the primary pulley and the secondary pulley. A belt type continuously variable transmission that changes in stages, a first oil supply nozzle that supplies lubricating oil to a belt winding start position of at least one of the primary pulley and the secondary pulley, and a belt of the one pulley A second oil supply nozzle for supplying lubricating oil to the winding end position, and an oil supply distribution changing means for changing an oil supply amount from the first oil supply nozzle and an oil supply amount from the second oil supply nozzle according to a gear ratio. The one pulley is the primary pulley, and the oil supply distribution changing means is configured to reduce the oil supply amount from the first oil supply nozzle as the gear ratio decreases. The ratio of the quantity of oil from the second oil supply nozzle is increased, the belt type continuously variable transmission is provided, characterized in that.

  According to the above aspect, since a portion with a large amount of heat generation can be efficiently cooled, the amount of lubricating oil can be reduced and the driving load of the oil pump can be reduced.

1 is a schematic configuration diagram of a belt type continuously variable transmission according to an embodiment of the present invention. It is AA sectional drawing of FIG. It is the figure which showed the analysis result of the emitted-heat amount of the belt in the highest High gear ratio. It is the figure which showed the analysis result of the emitted-heat amount of the belt in the lowest Low gear ratio.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows a schematic configuration of a belt type continuously variable transmission (hereinafter referred to as “CVT”) 10 according to an embodiment of the present invention. In the following description, “speed ratio” is a value obtained by dividing the input rotational speed of the CVT 10 by the output rotational speed of the CVT 10. The “lowest speed ratio” is the maximum speed ratio of the CVT 10, and the “highest speed ratio” is the minimum speed ratio of the CVT 10. The CVT 10 is the primary pulley 11 on the input side, the secondary pulley 12 on the output side, and the pulley 11 , 12 and a belt 13 wound around. Each of the pulleys 11 and 12 includes a fixed conical plate, a movable conical plate that is arranged with a sheave surface facing the fixed conical plate and forms a groove between the fixed conical plate, and the movable conical plate. And a hydraulic cylinder provided on the back surface for displacing the movable conical plate in the axial direction. When the hydraulic pressure supplied to the hydraulic cylinder is adjusted by the hydraulic circuit 21, the groove width of the pulleys 11 and 12 changes, the contact radius between the belt 13 and the pulleys 11 and 12 changes, and the gear ratio of the CVT 10 changes steplessly. To do. FIG. 1 shows the position Ph of the belt 13 at the highest gear ratio and the position Pl of the belt 13 at the lowest gear ratio. During the shift, the position of the belt 13 changes between the position Ph and the position Pl.

  The CVT 10 also includes a first oil supply nozzle 15 and a second oil supply nozzle 16 at a substantially intermediate position between the primary pulley 11 and the secondary pulley 12.

  The first oil supply nozzle 15 and the second oil supply nozzle 16 are located on both sides of the center line C passing through the center of the primary pulley 11 and the center of the secondary pulley 12 and at substantially equidistant positions from the center line C. It is arranged inside 13 trajectories (in the drawing, in the region inside the position Ph and inside the position Pl).

  The first oil supply nozzle 15 supplies lubricating oil toward the belt winding start position Ss of the secondary pulley 12, more specifically toward the inside of the belt 13 at the belt winding start position Ss. The belt winding start position Ss is a position at which the belt 13 starts to contact the secondary pulley 12 and moves in the pulley radial direction according to the gear ratio of the CVT 10. For this reason, the opening direction of the first oil supply nozzle 15 is adjusted so that the lubricating oil is supplied toward the approximate center of the locus of the belt winding start position Ss, and the lubricating oil is supplied to the belt winding start position Ss regardless of the gear ratio. To be supplied.

  On the other hand, the second oil supply nozzle 16 supplies the lubricating oil toward the belt winding end position Es of the secondary pulley 12, more specifically toward the inside of the belt 13 at the belt winding end position Es. The belt winding end position Es is a position where the belt 13 wound around the secondary pulley 12 starts to be separated from the secondary pulley 12 and moves in the pulley radial direction according to the gear ratio of the CVT 10. For this reason, the opening direction of the second oil supply nozzle 16 is adjusted so as to supply the lubricating oil toward the approximate center of the locus of the belt winding end position Es, and the lubricating oil is supplied to the belt winding end position Es regardless of the gear ratio. To be supplied.

  FIG. 2 is a cross-sectional view taken along line AA in FIG. The second oil supply nozzle 16 is arranged so that the lubricating oil supplied from the oil supply port hits the belt 13 regardless of the gear ratio of the CVT 10. The same applies to the first oil supply nozzle 15.

  Returning to FIG. 1, the hydraulic circuit 21 supplies oil pressure supplied from the oil pressure generated by the oil pump 22 to the hydraulic cylinders of the pulleys 11 and 12, oil pressure supplied to a clutch constituting a forward / reverse switching mechanism (not shown), and a torque converter (not shown). Is a hydraulic circuit that adjusts the hydraulic pressure supplied to the lockup clutch, and includes a plurality of control valves. The hydraulic oil that has passed through the plurality of control valves is cooled by the cooler 23, the foreign matter is removed by the filter 24, and then the first supply pipe 25 and the second supply pipe 26 branch from the downstream position of the filter 24. The oil is supplied to the first oil supply nozzle 15 and the second oil supply nozzle 16.

  The first supply pipe 25 and the second supply pipe 26 are respectively provided with a first flow rate adjustment valve 31 and a second flow rate adjustment valve 32. The first and second flow rate adjusting valves 31 and 32 are, for example, solenoid valves. By adjusting the opening degree (duty ratio) of the first and second flow rate adjusting valves 31, 32, the amount of oil supplied from the first and second oil supply nozzles 15, 16 to the first and second oil supply nozzles 15, 16 is reached. The distribution ratio of the lubricant can be changed.

  The transmission controller 40 includes a CPU, a storage device including a RAM / ROM, an input / output interface, and the like. The input / output interface includes a signal from the primary rotational speed sensor 41 that detects the rotational speed of the primary pulley 11, a signal from the secondary rotational speed sensor 42 that detects the rotational speed of the secondary pulley 12, and the opening degree of the accelerator pedal. Signals such as an accelerator opening sensor to detect, an oil temperature sensor to detect the oil temperature of the CVT 10, and an inhibitor switch to detect the position of the select lever are input.

  The transmission controller 40 performs various arithmetic processes on the input signal, generates a shift control signal, outputs the generated shift control signal to the hydraulic circuit 21 via the input / output interface, and shifts the CVT 10. .

  The transmission controller 40 divides the rotational speed of the primary pulley 11 by the rotational speed of the secondary pulley 12 to calculate the transmission ratio of the CVT 10, and based on the calculated transmission ratio, the first and second flow rate adjusting valves 31, 32. Adjust the opening.

  Specifically, as the gear ratio decreases, the opening degree of the first flow rate control valve 31 is increased and the opening degree of the second flow rate control valve 32 is decreased, so that the second oil supply nozzle 16 moves to the belt winding end position Es. The ratio of the amount of oil supplied from the first oil supply nozzle 15 to the belt winding start position Ss is increased. This is because, on the secondary pulley 12 side, as will be described later, the amount of heat generated at the belt winding start position Ss increases as the gear ratio decreases.

  Then, the effect of this embodiment is demonstrated.

  3A and 3B are diagrams showing the analysis results of the heat generation amount of the belt 13. 3A shows the amount of heat generated when the gear ratio of the CVT 10 is the highest gear ratio, and FIG. 3B shows the amount of heat generated when the gear ratio of the CVT 10 is the lowest gear ratio. In the figure, Sp and Ep indicate a belt winding start position and a belt winding end position in the primary pulley 11, and Ss and Es indicate a belt winding start position and a belt winding end position in the secondary pulley 12. .

  The amount of heat generated by the belt 13 varies depending on the position and the gear ratio of the CVT 10 and has the following tendency.

  Primary pulley 11 side: As the gear ratio becomes smaller, the heat generation at the belt winding end position Ep becomes more conspicuous than the belt winding start position Sp, and the heat generation amount at the belt winding end position Ep increases.

  Secondary pulley 12 side: The heat generation at the belt winding start position Ss becomes more conspicuous than the belt winding end position Es as the gear ratio decreases, and the heat generation amount at the belt winding start position Ss increases.

  In the above embodiment, the cooling efficiency of the belt 13 is improved by supplying lubricating oil to the belt 13 corresponding to such a tendency.

That is, according to the above embodiment, the amount of oil supplied from the first oil supply nozzle 15 and the amount of oil supplied from the second oil supply nozzle 16 are changed according to the gear ratio, and the oil supply from the second oil supply nozzle 16 becomes smaller as the gear ratio becomes smaller. The ratio of the amount of oil supplied from the first oil supply nozzle 15 to the amount is increased. As a result, it is possible to efficiently cool the portion with a large amount of heat generation (belt winding start position Ss of the secondary pulley 12), and the amount of lubricating oil can be reduced and the driving load of the oil pump 22 can be reduced ( Action and effect corresponding to claim 1 ).

In the above embodiment, the change in the distribution ratio of the lubricating oil to the first and second oil supply nozzles 15 and 16 is connected to the first supply pipe 25 and the second oil supply nozzle 16 connected to the first oil supply nozzle 15. The flow rate adjustment valves 31 and 32 provided in the second supply pipes 26 are used. According to this configuration, the distribution ratio of the lubricating oil to the first and second oil supply nozzles 15 and 16 can be changed with a simple configuration (operational effect corresponding to claim 3 ).

Further, according to the above embodiment, the first and second oil supply nozzles 15 and 16 are on the inner side of the trajectory of the belt 13 and the center line C connecting the center of the primary pulley 11 and the center of the secondary pulley 12 is defined. It is arranged on both sides across. According to this arrangement, it is possible to supply lubricating oil at a pinpoint to the belt winding start position Ss and the belt winding end position Es (effect corresponding to claim 4 ).

  The embodiment of the present invention has been described above, but the above embodiment is merely one example of application of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above embodiment. is not.

  For example, in the said embodiment, although the 1st and 2nd oil supply nozzles 15 and 16 supply lubricating oil to the secondary pulley 12 side, it supplies to the primary pulley 11 side, or the primary pulley 11 side and the secondary pulley 12 side You may make it supply to both.

On the primary pulley 11 side, as described above, the heat generation at the belt winding end position Ep becomes more significant than the belt winding start position Sp as the gear ratio decreases, and the heat generation amount at the belt winding end position Ep increases. Have Therefore, in the configuration of supplying to the primary pulley 11 side, the first and second flow control are performed so that the ratio of the amount of oil supplied from the second oil supply nozzle 16 to the amount of oil supplied from the first oil supply nozzle 15 increases as the gear ratio decreases. The opening degree of the valves 31 and 32 is adjusted. As a result, it is possible to efficiently cool the portion where the amount of heat generation is large (the belt winding end position Ep of the primary pulley 11), and it is possible to reduce the amount of lubricating oil and reduce the driving load of the oil pump 22 ( (Function and effect corresponding to claim 2 )

10 Belt type continuously variable transmission (CVT)
11 Primary pulley 12 Secondary pulley 15 First oil nozzle 16 Second oil nozzle 22 Oil pump 25 First supply pipe (first supply passage)
26 Second supply pipe (second supply passage)
31 1st flow regulating valve (fuel supply distribution changing means)
32 Second flow adjustment valve (fuel supply distribution changing means)
40 Transmission controller

Claims (4)

A belt type continuously variable transmission in which a belt is looped between an input-side primary pulley and an output-side secondary pulley, and the gear ratio is changed continuously by changing the groove width of the primary pulley and the secondary pulley. And
A first oil supply nozzle that supplies lubricating oil to a belt winding start position of at least one of the primary pulley and the secondary pulley;
A second oiling nozzle for supplying lubricating oil to a belt winding end position of the one pulley;
Oil distribution changing means for changing the amount of oil supplied from the first oil supply nozzle and the amount of oil supplied from the second oil supply nozzle according to the gear ratio;
With
The one pulley is the secondary pulley;
The oil distribution change means increases the ratio of the amount of oil supplied from the first oil supply nozzle to the amount of oil supplied from the second oil supply nozzle as the gear ratio decreases.
A belt type continuously variable transmission.   A belt type continuously variable transmission in which a belt is looped between an input-side primary pulley and an output-side secondary pulley, and the gear ratio is changed continuously by changing the groove width of the primary pulley and the secondary pulley. And
  A first oil supply nozzle that supplies lubricating oil to a belt winding start position of at least one of the primary pulley and the secondary pulley;
  A second oiling nozzle for supplying lubricating oil to a belt winding end position of the one pulley;
  Oil distribution changing means for changing the amount of oil supplied from the first oil supply nozzle and the amount of oil supplied from the second oil supply nozzle according to the gear ratio;
With
  The one pulley is the primary pulley;
  The oil distribution change means increases the ratio of the amount of oil supplied from the second oil supply nozzle to the amount of oil supplied from the first oil supply nozzle as the gear ratio decreases.
A belt type continuously variable transmission.   The belt-type continuously variable transmission according to claim 1 or 2,
  A first supply passage is connected to the first oil supply nozzle, and lubricating oil is supplied through the first supply passage,
  A second supply passage is connected to the second oil supply nozzle, and lubricating oil is supplied through the second supply passage,
  The oil distribution change means is constituted by a first flow rate adjustment valve provided in the first supply passage and a second flow rate adjustment valve provided in the second supply passage.
A belt type continuously variable transmission.   The belt-type continuously variable transmission according to any one of claims 1 to 3,
  The first and second oil supply nozzles are disposed on both sides of a line connecting the center of the primary pulley and the center of the secondary pulley inside the belt trajectory.
A belt type continuously variable transmission.

Images