JPH08254260A - Lubrication device of belt type continuously variable transmission - Google Patents

Abstract

PURPOSE: To optimize the supply amount of a lubricating oil between a belt and a pulley of a belt type continuously variable transmission and reduce drive loss of a hydraulic pump. CONSTITUTION: Oil supply nozzles 11, 12 for belt lubrication are provided in each of an input pulley 1 and an output pulley 2. On the halfway of a passage which connects a hydraulic pump 7 and each oil supply nozzle, a control valve 14 which supplies discharge oil of the hydraulic pump 7 to each oil supply nozzle 11, 12 reciprocally is provided so that an oil supply ratio to the input pulley 1 side is increased as gear change ratio increases.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricating device for a belt type continuously variable transmission.

[0002]

2. Description of the Related Art As a conventional lubricating device for a belt type continuously variable transmission, for example, the actual opening 63-75.
There is one disclosed in Japanese Patent No. 661.

In this lubrication system, the oil supply nozzle of the belt type continuously variable transmission has been attached only to either one of the input pulley and the output pulley, and both the input side and the output side are provided. In order to sufficiently lubricate the belt and pulley, an excessive amount of lubrication flow is required than the actually required lubrication flow rate, and it is necessary to solve the problem that the drive pump becomes large and drive loss increases. For this reason, oil supply nozzles are provided in the vicinity of each of the input pulley and the output pulley, and the two oil supply nozzles supply the lubricating oil to the belt and the pulley.

However, since this lubricating device is not provided with the means for adjusting the flow rate of the lubricating oil, the lubricating flow rate to each pulley is always constant. In this case, the frictional state on the input side and the output side is the highest. Inevitably, the lubrication flow rate must be set independently or identically according to the severe conditions of, and the total sum of the lubrication flow rate set becomes excessive with respect to the total lubrication flow rate required during actual belt operation. However, there is still a problem that the drive pump becomes larger and the drive loss increases.

On the other hand, Japanese Patent Laid-Open No. 60-95273 discloses that the lubricating flow rate is variably controlled according to at least one of the vehicle speed or the engine speed and the load.

However, in this apparatus, since only one lubrication nozzle is prepared for the belt, it is impossible to lubricate both the input side and output side belts and pulleys without excess or deficiency. Further, even if the lubricating flow rate is variable, if the drive pump is a fixed displacement pump, the volume of the pump is determined by the maximum required flow rate, so the drive loss of the pump cannot be reduced only by the variable flow rate control.

Even if an oil supply nozzle is provided near each of the input pulley and the output pulley and the lubricating flow rate is variably controlled according to the vehicle speed or the engine speed, the vehicle speed and the engine speed can be controlled. Since it is not possible to accurately detect the gear ratio of the belt from the information, it is not possible to set the required lubrication flow rate for each pulley, and therefore it is not possible to perform proper lubrication. Even if the lubrication flow rate can be varied according to the vehicle speed or engine speed, if the drive pump has a fixed capacity, the pump volume will be determined by the maximum required flow rate, so the drive loss of the pump can be reduced only by variable flow rate control. Can't do

SUMMARY OF THE INVENTION The present invention aims to solve the problems of the prior art, optimize the amount of lubricating oil supplied between the belt and pulley of a belt type continuously variable transmission, and reduce the drive loss of the hydraulic pump. There is.

[0009]

According to a first aspect of the invention, oil supply nozzles for supplying belt lubricating oil are provided on the input pulley side and the output pulley side respectively, and the oil discharged from a hydraulic pump is supplied to each of the oil supply nozzles. In a belt-type continuously variable transmission having a passage for supplying the oil to the oil supply nozzle, a control valve for reciprocally increasing or decreasing the lubricating flow rate to each oil supply nozzle is provided in the middle of the passage, and the transmission ratio of the continuously variable transmission becomes larger. A means for controlling the control valve is provided so that the lubricating oil supply ratio on the input pulley side increases.

According to a second aspect of the invention, the control means of the first aspect of the invention detects the position of the movable pulley of the input pulley or the output pulley, and moves the input pulley so that the movable pulley moves to a position where the gear ratio is high. The control valve shall be controlled so that the side lubricating oil supply rate increases.

According to a third aspect of the present invention, the control means of the second aspect is configured as a link mechanism for transmitting the movement of the movable pulley of the input pulley or the output pulley to the control valve.

According to a fourth aspect of the present invention, the control valve according to any of the first to third aspects is provided in a first port for supplying lubricating oil from a hydraulic pump to an oil supply nozzle on the input pulley side and an oil supply nozzle on the output pulley side. A second port for supplying and a valve body that reciprocally moves into and out of these two ports, and the port opening area is reduced as the amount of entry of the valve body into the port increases. To do.

[0013]

The frictional heat generated between the belt and the pulley of the continuously variable transmission will be relatively large on the side where the contact circumferential length between the belt and the pulley is small, that is, as the gear ratio becomes larger, as will be described later in detail. The heat load on the output pulley side tends to increase as the gear ratio on the input pulley side decreases.

In the first aspect of the present invention, the flow rate of the input pulley and the output pulley of the continuously variable transmission is increased according to the gear ratio of the continuously variable transmission as the gear ratio increases. Lubricating oil is supplied. At this time, a relatively small amount of lubricating oil is supplied to the oil supply nozzle on the output pulley side based on the reciprocal flow rate control via the control valve. On the other hand, as the gear ratio becomes smaller, the lubricating flow rate to the output pulley side increases and the lubricating flow rate to the input pulley side decreases.

In this way, the lubricating flow rate to the side where the thermal load becomes large is increased, and the lubricating flow rate to the side where the thermal load becomes small is reduced, so that the lubricating flow rate to each pulley becomes a thermal load. On the other hand, it is optimally controlled so that there is no excess or deficiency and the total lubrication flow rate supplied to each pulley is always suppressed to a constant value, so the load on the hydraulic pump that supplies lubricating oil to each oil supply nozzle is always the minimum required. Can be suppressed to.

According to the second aspect of the invention, the gear ratio is determined based on the position of the movable pulley that constitutes the input pulley or the output pulley of the continuously variable transmission, and the input pulley is increased as the movable pulley moves to a position where the gear ratio is high. Since the control valve is controlled so that the side lubricating oil supply rate increases, it is possible to accurately control the lubricating flow rate with respect to the change of the gear ratio by the continuously variable transmission. further,
In the third aspect, the change in the gear ratio is directly transmitted to the control valve via the link mechanism as the change in the position of the movable pulley, so that the change in the gear ratio can be reflected in the lubricating flow rate with a simple configuration.

In the fourth aspect of the invention, the lubricating flow rate to each oil supply nozzle is reciprocally controlled based on the reciprocating motion of the valve element between the two ports communicating with the input pulley side oil supply nozzle and the output pulley side oil supply nozzle. To be done. In this case, the desired flow rate control can be easily realized with the control valve having a simple structure.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1 (FIG. 4), reference numerals 1 to 3 respectively indicate an input pulley, an output pulley and a belt which constitute a belt type continuously variable transmission mechanism.

The input pulley 1 includes an input shaft 1a connected to an output shaft 6a of an engine 6 via a torque converter 4 and a clutch 5, a fixed pulley 1b fixed to the input shaft 1a, and an input shaft 1a. It comprises a movable pulley 1c which is hydraulically controlled so as to slide in the axial direction and to have a variable relative distance from the input fixed pulley 1b. The output pulley 2 includes an output shaft 2a connected to a drive shaft side of a vehicle (not shown) and a fixed pulley 2 fixed to the output shaft 2a.
b, and a movable pulley 2c that is hydraulically controlled so as to slide on the output shaft 2a in the axial direction so that the relative distance between the fixed pulley 2b and the fixed pulley 2b is variable.

As shown in FIGS. 2 and 3, the belt 3 has a structure in which a large number of elements 3b are supported on a ring 3a having a laminated structure.
The rotational force is transmitted based on the contact frictional force generated between the both side surfaces of the element 3b and the conical surface of the pulley while being wound between them.

The gear ratio (= input / output shaft rotation speed / output shaft rotation speed) of this continuously variable transmission mechanism is determined by setting the radius of the portion where the belt 3 contacts the input pulley 1 and the output pulley 2 as the movable pulleys 1c, 2c is controlled by reciprocally hydraulically controlling and changing the position, that is, the pulley 1 on the input side.
As the contact radius of the belt 3 is reduced by widening the distance between b and 1c, and the contact radius is increased by narrowing the distance between the output pulleys 2b and 2c, the gear ratio becomes larger, and conversely, the input pulley 1b. , 1c and the output side pulleys 2b and 2c are widened, the gear ratio becomes smaller.

The distance between the respective pulleys on the input and output sides, that is, the positions of the movable pulleys 1c and 2c is determined by the hydraulic pump 7.
Is controlled by the oil pressure supplied via the pressure adjusting means 8 so that the sizes of the pulleys 1c and 2c reciprocally change. Such hydraulic control is executed by a gear ratio control means (not shown) according to a predetermined gear shift pattern that is set in advance so that the gear ratio becomes a predetermined gear ratio according to the operating state of the vehicle.

The above points are similar to those of the known continuously variable automatic transmission, but in this embodiment, in order to supply the lubricating oil to the pulleys 1 and 2 on the input / output side, the oil supply nozzles 11 and 12 are respectively supplied. In addition, a control valve 14 for reciprocally controlling the lubricating flow rate of each nozzle 11, 12 is provided in the middle of a passage 13 for supplying the lubricating oil from the pressure adjusting means 8 to each nozzle 11, 12. The control valve 14 is controlled by the control means 15 such that the amount of lubricating oil to the input pulley 1 side increases as the gear ratio is detected by detecting the gear ratio of the continuously variable transmission, that is, the gear ratio becomes LOW. To be done.

4 and 5 show examples of the control means 15 and the control valve 14, respectively. The control means shown in FIG. 5 controls the opening degree of the control valve by the link mechanism so that the lubricating flow rate changes according to the position change of the movable pulley. More specifically, in this case, a concave groove 1d is formed on the entire outer peripheral surface of the input side movable pulley 1c, and the tip portion 15b of the pulley position detector 15a is slidably engaged with the concave groove 1d. are doing. The pulley position detector 15a is slidably supported in the pulley axial direction, and moves in the axial direction as the movable pulley 1c moves. The other end of the detector 15a is connected to the spool-shaped valve body 14a of the control valve 14 as shown in FIG. 5, and the valve body 14a is configured to open and close as the pulley moves. Has been done.

The control valve 14 comprises the valve body 14a and a housing 14b in which the valve body 14a is slidably accommodated, and the housing 14b is provided with a hydraulic pump 7 adjusted to a predetermined amount via a pressure adjusting means 8. Inlet port 1 into which the lubricating oil of
4c and first and second ports 14d and 14e for branching the inflowing lubricating oil to the oil supply nozzle 11 on the input pulley 1 side and the oil supply nozzle 12 on the output pulley 2 side, respectively. Each of the ports 14d and 14e forms an annular passage on the inner surface of the housing 14b so as to surround the valve body 14a, while the cylindrical surface of the valve body 14a is opposed to the inside so as to oppose the annular passage. A pair of inclined flat portions 14f,
14 g are formed.

FIG. 5 shows the control valve position when the movable pulley 1c is at the lowest LOW position. At this time, most of the port 14e on the output pulley side is blocked by the cylindrical surface of the valve body 14a, and the lubricating oil amount Ls on the output pulley side is extremely narrowed to a small flow rate. On the other hand, the port 14d on the input pulley side
Since the distance from the valve flat portion 14f, that is, the flow passage cross-sectional area, becomes maximum, the lubricating flow rate Lp on the input pulley side is controlled to a relatively large flow rate. Similarly, when the movable pulley 1c reaches the maximum HI position, the valve element 14a moves to the right in FIG. 5, and the flow rate setting state opposite to that described above is set.

FIG. 6 shows the amount of lubricating oil Lp to the pulleys 1 and 2 due to the change of the input pulley position, that is, the gear ratio.
It shows the flow rate control characteristic of Ls.
p and Ls are reciprocally controlled such that one increases and the other decreases, and when the gear ratio = 1, the flow rates are equal to each other. Further, the total flow rate of Lp and Ls is always constant regardless of the gear ratio.

In describing the operation of the above embodiment, first, the principle of frictional heat generation between the V-belt and the pulley of the continuously variable transmission will be described.

FIG. 2 shows an example of the structure of a metal V-belt used in a belt type continuously variable transmission. This V-belt 3 has a laminated ring 3a composed of a plurality of endless rings as described above. The ring 3a is composed of a large number of elements 3b arranged in the longitudinal direction without gaps. Each element 3b is allowed to be bent inward as an element row by the taper surface 3c formed in the lower half portion of the front surface, which allows the pulleys 1 and 2 to be wound.

By the way, the contact point A between the elements is
It is separated from the contact surface B between the ring 3a and the element 3b inward in the radial direction by r. This diameter difference r is about 1 mm, but because of this, the belt 3a moving outside at the bent portion wound around the pulley has a smaller angular velocity than the element 3b moving inside and slips. At this time, for example, as shown in FIG. 8A, when the gear ratio is large on the LOW side, the winding angle of the belt 3 or the contact circumference with the pulley is closer to the output pulley 2 side than the input pulley 1 side. Is larger, and the frictional force between the ring 3a and the element 3b is larger accordingly, so that the slip occurs on the side of the input pulley 1 where the frictional force is relatively small. On the contrary, as shown in FIG. 8B, when the gear ratio is small on the HI side, the ring 3a and the element 3b are substantially integrated on the input pulley 1 side where the belt winding angle is large. The relative slip between the ring 3a and the element 3b occurs mainly on the output pulley 2 side.

That is, in such a V-belt for a continuously variable transmission, the ring 3a and the element 3b are on the input pulley 1 side on the LOW side where the gear ratio is larger than 1, and the gear ratio is smaller than 1. On the HI side, relative slippage occurs on the output pulley 2 side. Friction heat is generated on the contact surface between the ring 3a and the element 3b due to this relative sliding.
In FIG. 9, the belt circumference is 700 mm and the distance between the pulley axes is 16
0 mm belt type continuously variable transmission, input shaft rotation speed =
It is the calculation result of the relative slip speed between the element and the ring that occurs when the gear ratio is changed by operating at 4000 rpm. It can be seen that the occurrence of slipping changes at the gear ratio = 1 and that the relative slip speed increases and the amount of heat generation also increases as the gear ratio becomes LOW or HI.

Here, assuming that the lubricating flow rate required at the maximum LOW is (input, output) = (2,1) and the lubricating flow rate required at the maximum HI ratio is (input / output) = (1,2). In the case of the conventional technology in which the lubricating oil is provided to the belt and the pulley at a constant flow rate by the oil supply nozzles provided near the input pulley and the output pulley, in order to achieve sufficient lubrication over the entire operating condition, As described above, it is necessary to set the lubrication flow rate independently or the same on the input side and the output side according to the most severe frictional condition. Maximum H on the output pulley side
The required 2 must always be supplied at the time of I, so the total required lubricating flow rate is 4. Considering the operating conditions of maximum LOW, the necessary and sufficient lubricating flow rate is 2 on the input pulley side, but the lubricating flow rate of 2 remains at the output pulley side even though the required lubricating flow rate is 2. It turns out that. Similarly, considering the maximum HI operating condition, the supply amount is 1 excessively on the input pulley side. That is, in the conventional device, the excessive supply of the lubricating oil is eventually generated by 1 under all the operating conditions, which is the driving loss of the hydraulic pump.

On the other hand, in the above embodiment, the lubricating flow rate is controlled with the characteristics shown in FIG. As the continuously variable transmission shifts from LOW to HI, the relative slip on the input pulley 1 side, that is, the calorific value decreases, and the shift value from HI to LOW decreases the calorific value on the output pulley 2 side. It can be seen from the characteristics that the required flow rates can be supplied to the pulleys 1 and 2 without excess or deficiency. The required total lubricating oil flow rate in this case is always 3. Therefore, it is possible to reduce the required lubricating flow rate by one as compared with the conventional technique, and by reducing the lubricating flow rate, the drive pump can be downsized or the drive loss can be reduced.

In the above embodiment, the gear ratio of the continuously variable transmission is represented by the position of the movable pulley, and the opening of the control valve 14 is adjusted by the link mechanism including the detector 15a so as to respond to the position. Although it is controlled mechanically,
The control means of the control valve 14 is not limited to this, and for example, the gear ratio of the continuously variable transmission is detected from the command value of the gear shift control circuit or the control oil pressure of the pulley ratio, and electromagnetically controlled based on this detection result. It is also possible to control the opening of the valve.

[0036]

As described above, according to the first aspect of the present invention, the flow rate to the oil supply nozzle on the input pulley side increases as the gear ratio of the input pulley and the output pulley of the continuously variable transmission increases. Since the lubrication oil is supplied reciprocally, the total lubrication flow rate supplied to each pulley is always kept constant while controlling the lubrication flow rate to each pulley to an appropriate flow rate that is sufficient for the thermal load. Therefore, it is possible to suppress the drive loss of the hydraulic pump to a necessary minimum and improve the efficiency of the drive system.

In the second invention, in the first invention, the gear ratio is determined based on the position of the movable pulley which constitutes the input pulley or the output pulley of the continuously variable transmission. The lubricating flow rate can be controlled more accurately with respect to the change in the gear ratio due to.

Further, in the third aspect of the invention, the change of the gear ratio of the first aspect of the invention is directly transmitted to the control valve via the link mechanism as the change of the position of the movable pulley, so that the structure is simple. It is possible to control the lubrication flow rate during the period.

In a fourth invention, the control valve of each of the above inventions is
The lubrication flow rate to each oil supply nozzle is controlled reciprocally based on the reciprocating motion of the valve element between the two ports communicating with the input pulley side oil supply nozzle and the output pulley side oil supply nozzle, respectively. The desired flow rate control can be easily realized with the control valve.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of the present invention.

FIG. 2 is a front sectional view of a belt.

FIG. 3 is a side view of a main part of the belt.

FIG. 4 is a schematic configuration diagram of a control unit of the above embodiment.

FIG. 5 is a schematic cross-sectional view of the control valve of the above embodiment.

FIG. 6 is a characteristic diagram showing a flow rate characteristic of the control valve.

FIG. 7 is a characteristic diagram showing a flow rate control characteristic of a conventional lubricating device.

FIG. 8 is an explanatory diagram showing the principle of relative slip between the element and the ring of the belt.

FIG. 9 is a characteristic diagram showing a change in relative sliding speed between the belt element and the ring in relation to the pulley ratio.

[Explanation of symbols]

 1 Input Side Pulley 1a Input Shaft 1b Fixed Pulley 1c Movable Pulley 2 Output Side Pulley 2a Output Shaft 2b Fixed Pulley 2c Movable Pulley 3 Belt 3a Ring 3b Element 6 Engine 7 Hydraulic Pump 8 Pressure Regulator 11 Oil Supply Nozzle on Input Pulley 12 Output pulley side oil supply nozzle 14 Control valve 14a Control valve body 14d Control valve first port 14e Control valve second port 15 Control means (link mechanism) 15a Pulley position detector

Claims (4)

[Claims] 1. A belt-type non-pressurizer having an oil supply nozzle for supplying a lubricating oil for a belt to each of an input pulley side and an output pulley side, and a passage for supplying oil discharged from a hydraulic pump to each of the oil supply nozzles. In a continuously variable transmission, a control valve that reciprocally increases and decreases the lubricating flow rate to each oil supply nozzle is provided in the middle of the passage, and the larger the gear ratio of the continuously variable transmission, the greater the proportion of lubricating oil supplied to the input pulley side. A lubricating device for a belt type continuously variable transmission, characterized in that means for controlling the control valve is provided. 2. The control means detects the position of the movable pulley of the input pulley or the output pulley, and the lubricating oil supply ratio on the input pulley side increases as the movable pulley moves to a position where the gear ratio is large. The lubrication device for a belt type continuously variable transmission according to claim 1, wherein the control valve is controlled by the control valve. 3. The lubrication for a belt type continuously variable transmission according to claim 2, wherein the control means is configured as a link mechanism for transmitting the movement of the movable pulley of the input pulley or the output pulley to the control valve. apparatus. 4. The control valve comprises: a first port for supplying lubricating oil from a hydraulic pump to an oil supply nozzle on the input pulley side; a second port for supplying the oil supply nozzle to an oil supply nozzle on the output pulley side; And a valve element that reciprocally moves forward and backward, and the port opening area decreases as the amount of entry of the valve element into the port increases. A belt type continuously variable transmission lubrication device according to any one of the preceding claims.