JP4429464B2 - Apparatus for detecting internal pressure of fluid-mechanical power conversion device and torque converter including the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention, as represented by the torque converter, the fluid outputs the force of the fluid flow is converted to mechanical power - the mechanical power converting apparatus, the inner pressure detector and pressure detection device for detecting the internal pressure The present invention relates to a provided torque converter.
[0002]
[Prior art]
As a technique for detecting the hydraulic pressure inside the torque converter as a variable for torque converter control, particularly lock-up hydraulic pressure control, there is a technique described in, for example, Japanese Patent Laid-Open No. 6-300127. The contents will be described below with reference to FIGS.
[0003]
FIG. 3 is a hydraulic circuit diagram of a clutch hydraulic control valve of the lockup clutch. In FIG. 3, the pump 1 is connected to the piston chamber 5 of the lockup clutch 3 of the torque converter 2 through a pipe line 4 provided with a main relief valve 10. An electronic clutch hydraulic control valve (hereinafter abbreviated as ECMV) 6 is provided in the pipeline 4. Pressure sensors 18 and 19 are provided on the inlet line 14 and the outlet line 15 for the pressure oil of the torque converter 2 for lock-up clutch control, respectively. For the same control, the torque converter 2 includes a rotation sensor 8 that measures the rotation speed of the input shaft and a rotation sensor 9 that measures the rotation speed of the output shaft. Signals from the rotation sensor 8 and the rotation sensor 9 are input to the controller 7, and further from the pressure sensor 18 that measures the inlet pressure P 1 of the torque converter 2 and from the pressure sensor 19 that measures the outlet pressure P 2. Each signal is input. Based on these measured values, the controller 7 calculates the oil pressure of the lockup clutch using a calculation formula described later, and outputs an electric signal corresponding to the calculated oil pressure to the ECMV 6.
[0004]
Next, the structure and operation of the ECMV 6 will be described. The ECMV 6 includes a pressure control valve 31 that controls the hydraulic pressure (hereinafter referred to as clutch pressure) of the piston chamber 5 of the torque converter 2, a flow rate detection valve 32, and a sensor for detecting filling (a state in which the piston chamber 5 is filled with pressure oil). Part 33. The pressure control valve 31 is controlled by the controller 7, and the detection signal of the sensor unit 33 is input to the controller 7.
[0005]
When the clutch is to be engaged, the controller 7 outputs a predetermined command current to the solenoid 46 of the pressure control valve 31, and the pressure control valve 31 opens for a stroke corresponding to the command current, and the oil from the pump 1 is flowed. The gas is fed into the piston chamber 5 through the detection valve 32. At this time, a differential pressure is generated before and after the flow rate detection valve 32, and the flow rate detection valve 32 moves to the left in FIG. After this, when the piston chamber 5 is filled with oil, the filling is completed and the oil no longer flows, so there is no differential pressure before and after the flow rate detection valve 32. At this time, the flow rate detection valve 32 moves to the right in FIG. 3 to operate the sensor unit 33, and outputs a filling end signal to the controller 7. When the controller 7 receives the filling end signal, the controller 7 corrects the command current and finely adjusts the opening of the pressure control valve 31 so that the clutch pressure becomes the target value.
[0006]
Thus, the clutch pressure is controlled based on the command current I from the controller 7 by the operation of the ECMV 6.
[0007]
FIG. 2 is a cross-sectional view of the lock-up clutch portion. The clutch pressure supplied to the piston chamber 5 urges the piston 71 rightward in the drawing as shown in FIG. As a result, a frictional force is generated between the two clutch disks 72, 72 and the clutch plate 73 sandwiched therebetween, and the clutch is engaged and the input shaft and the output shaft are directly connected. The internal pressure of the torque converter 2 is acting in a chamber opposite to the piston chamber 5 where the clutch pressure acts via the piston 71, and the piston 71 is urged to the left in the figure.
[0008]
Next, a method for determining the clutch pressure PL / C of the lockup clutch of the torque converter 2 will be described with reference to FIG.
[0009]
The pushing force FP of the piston 71 includes the static oil pressure obtained from the outer diameter D0 and the inner diameter Di of the piston 71 and the clutch pressure PL / C, the outer diameter D0 and the inner diameter Di of the piston 71, and the input shaft rotational speed of the torque converter 2. It is calculated as the sum of the dynamic oil pressure generated by the centrifugal force of the oil in the piston chamber 5 obtained based on NE.
[0010]
Further, the pushing back force FB of the piston 71 includes the outer diameter D0 of the piston 71, the inner diameter Di of the piston 71, the outer diameter d0 of the clutch disk 72, the inner diameter di of the clutch disk 72, the inlet pressure P1 of the torque converter 2 and the torque converter 2. Generated by the static oil pressure of the torque converter 2 determined by the outlet pressure P2, the centrifugal force of the oil in the torque converter 2 determined based on D0, Di, d0, di, NE and the output shaft rotational speed N1 of the torque converter 2. Calculated as the sum of dynamic oil pressure.
[0011]
When the lockup clutch pressure PL / C0 when the effective pushing force (= pushing force FP−pushback force FB) is zero is calculated, the following equation (1) is obtained.
[0012]
PL / C0 = (C1 x P1 + C2 x P2)
+ {(C3 × NE + C4 × N1) ² + (C5 × NE) ² } (1)
Here, C1, C2, C3, C4, and C5 are constants. Incidentally, since the first term on the right side of the above equation (1) is uniquely determined by the inlet pressure P1 and the outlet pressure P2, it is a static component of the torque converter internal pressure, and the second term on the right side is the input shaft rotational speed. Since it is uniquely determined by NE and the output shaft rotational speed N1, it can be said that it is a dynamic component of the torque converter internal pressure caused by the centrifugal force.
[0013]
That is, the pressure PL / C0 of the lock-up clutch when the effective pushing force is zero is the torque converter inlet pressure P1, the torque converter outlet pressure P2, the input shaft rotational speed NE, and the output shaft rotational speed N1. Is input to the controller 7 as a variable and calculated.
[0014]
If control is performed to add the oil pressure (PL / C0 + PL / Ci) with a value obtained by adding the constant oil pressure PL / Ci to the oil pressure PL / C0 obtained in the above procedure as the clutch oil pressure PL / C, then PL / C> PL / Since it is C0, the pushing force FP becomes larger than the pushing back force FB, the piston 71 moves in the clutch engagement direction, and the effective hydraulic pressure acting on the piston 71 (hydraulic pressure generating the effective pushing force) is PL / Ci (= PL / C-PL / C0).
[0015]
That is, even if PL / C0 changes due to changes in the inlet hydraulic pressure P1, the outlet hydraulic pressure P2, the input shaft rotational speed NE, and the output shaft rotational speed N1 of the torque converter 2, the controller 7 and the ECMV 6 change the PL / By making C follow, control is performed to keep PL / Ci at a constant target value and the effective pushing force constant.
[0016]
As described above, the above-described conventional technique measures the inlet pressure and outlet pressure of the torque converter, the input shaft speed of the torque converter, and the output shaft speed by the measuring means, and calculates these measured values. By inputting into the means and performing calculation, the internal pressure of the torque converter is indirectly detected and used for lockup control.
[0017]
[Problems to be solved by the invention]
However, in the above prior art, it is necessary to provide pressure sensors at two locations, the inlet and the outlet of the torque converter. Since two expensive pressure sensors are used, there is a problem that the cost increases in terms of both assembly and wiring man-hours and component costs. Further, since the pressure sensor is arranged at the pressure oil inlet / outlet of the torque converter, there is a problem that when the peak pressure is generated, the pressure sensor is directly subjected to the peak pressure, and the pressure sensor is damaged.
[0018]
The present invention has been made paying attention to the above-mentioned problems, and an object thereof is to provide an internal pressure detection device for a torque converter that is inexpensive and excellent in durability.
[0019]
[Means, actions and effects for solving the problems]
In order to achieve the above object, the present invention firstly provides a fluid-mechanical power conversion device that converts the force of fluid flow into mechanical power and outputs it, such as a torque converter, a fluid coupling, and a fluid retarder. in pressure detection device comprises a fluid bypass flow path, an inlet-side and outlet-side pressure loss means, a pressure detecting means. The fluid bypass channel is provided separately from the flow channel in which the fluid flowing in from the fluid inlet into the fluid-mechanical power conversion device performs work and flows out from the fluid outlet, and is bypassed from the fluid inlet to the fluid outlet. Connected . The inlet-side and outlet-side pressure loss means are respectively provided on the inlet downstream side of the bypass channel and on the outlet upstream side of the bypass channel . Pressure detection means, wherein was is generated between the inlet-side pressure loss means and said outlet-side pressure loss means detected an intermediate pressure between the input fluid pressure and output fluid pressure to the device, the intermediate pressure it is an internal pressure in the device with the detection value.
[0020]
According to the first configuration, only one pressure detection means is used for detecting the internal pressure in the fluid-mechanical power conversion device, and the internal pressure in the fluid-mechanical power conversion device can be detected by reducing assembly man-hours and component costs. The apparatus to be used can be configured at low cost.
[0021]
Second, in the internal pressure test DeSo location of the first configuration, the bypass passage is a bypass conduit, the pressure loss means provided in said two positions is a stop two pressure loss, the pressure detecting means the The pressure sensor is provided between both pressure loss restrictors.
[0022]
According to the second configuration, since the pressure loss means is provided by an inexpensive throttle, the manufacturing cost can be further reduced. In addition, since pressure loss restrictors are installed upstream and downstream of the pressure sensor used to detect the internal pressure in the fluid-mechanical power conversion device, the peak pressure generated at the inlet / outlet of the fluid-mechanical power conversion device can be reduced. The damage received is reduced and the life of the pressure sensor can be extended.
[0023]
Third, the fluid-mechanical power conversion device is a torque converter, bypassing the outside of the torque converter body between the pump blade side fluid inflow passage and the turbine blade side fluid outflow passage of the torque converter, The internal pressure detection device of the second configuration is provided.
[0024]
According to the third configuration, since the pressure sensor is disposed outside the torque converter, heat and vibration transmitted from the torque converter to the pressure sensor can be reduced, so that the pressure sensor is less damaged and the life of the pressure sensor is shortened. Can be extended.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a hydraulic circuit diagram of a clutch hydraulic control valve of a lockup clutch according to an embodiment of the present invention. Note that the difference in configuration between the embodiment of the present invention and the conventional embodiment is only the configuration of the portion related to the detection of the internal pressure of the torque converter. Therefore, the same components as those in FIG. 3 are denoted by the same reference numerals, and description thereof is omitted here.
[0026]
A branch point 14a is provided on the conduit 14 for supplying the pressure oil to the torque converter 2, a branch point 15a is provided on the conduit 15 for discharging the pressure oil from the torque converter 2, and the branch point is bypassed by the torque converter 2. A conduction pipe line 17 connecting the line 14a and the branch point 15a is provided by an external pipe. Two orifices 12 and 13 having a sufficiently smaller inner diameter than the pipe are provided in series on the conducting pipe 17, and the orifice 12 is arranged near the branch point 14a. The pressure sensor 11 is attached between the orifice 12 and the orifice 13. The pressure sensor 11 is connected to the controller 7 in a signal manner, and inputs the detected pressure P 3 to the controller 7.
[0027]
A part of the pressure oil supplied to the torque converter 2 passes through the conduction conduit 17. At this time, the pressure P3 detected by the pressure sensor 11 takes an intermediate value between the inlet pressure P1 and the outlet pressure P2 due to the partial pressure action caused by the resistance between the orifice 12 and the orifice 13. Specifically, according to the following equation (2).
[0028]
P3 = (Aα ² × P1 + Aβ ² × P2) / (Aα ² + Aβ ² ) (2)
Here, Aα is the opening area of the orifice 12, and Aβ is the opening area of the orifice 13. When the orifices 12 and 13 are selected so that Aα ² / Aβ ² = C1 / C2, the following equation (3) is established.
[0029]
PL / C0 = (C6 × P3)
+ {(C3 × NE + C4 × N1) ² + (C5 × NE) ² } (3)
here,
^{C6 = C1 × (Aα 2 +} Aβ 2) / Aα 2
= C2 × (Aα ² + Aβ ² ) / Aβ ² (4)
C1 and C2 are the constants C1 and C2 in the above (1). Substituting Equations (2) and (4) into Equation (3) results in the same as Equation (1).
[0030]
Therefore, the pressure P3 measured by the pressure sensor 11 is input to the controller 7, and the oil pressure PL / C0 can be obtained by the equation (3). Then, the clutch hydraulic pressure is controlled in the same procedure as described in the section of the prior art.
[0031]
That is, the controller 7 and the ECMV 6 add a hydraulic pressure (PL / C0 + PL / Ci) obtained by adding a predetermined hydraulic pressure PL / Ci to the hydraulic pressure PL / C0 as a clutch pressure PL / C, and use the hydraulic pressure PL / Ci as an effective hydraulic pressure. To act as. Then, control is performed to keep the effective oil pressure PL / Ci constant by making PL / C follow the change of PL / C0.
[0032]
Because of the configuration as described above, the conventional technique requires pressure sensors at two locations, the inlet and the outlet of the torque converter. However, according to the present embodiment, a conductive conduit that connects the inlet and the outlet of the torque converter. The pressure sensor may be disposed only at one position in the middle of the above. Therefore, the internal pressure detection device of the torque converter can be configured at low cost by reducing the man-hours and cost of assembly and wiring. In addition, since the throttles are arranged upstream and downstream of the pressure sensor used for detecting the internal pressure of the torque converter, the peak pressure generated at the entrance and exit of the torque converter can be reduced, and the pressure sensor can be provided by using an external pipe as the conduction line. Since it is disposed outside the housing of the torque converter, heat and vibration transmitted to the pressure sensor can be reduced, so that damage to the pressure sensor is reduced and the life of the pressure sensor can be extended.
[0033]
Here, in this embodiment, when C1 and C2 are substantially equal, or when there is no problem in accuracy even if the control is performed assuming that they are equal, Aα and Aβ may be set to be approximately equal. In such a case, the orifices 12 and 13 can be equivalent orifices or common parts. As a result, the number of items is reduced, the cost is reduced, and the possibility that the orifices 12 and 13 are mistakenly assembled is eliminated.
[0034]
Also, by substituting the mathematical expression “Aα = Aβ” into the above equation (4), the internal pressure PL / C0 of the torque converter is obtained by the following equation (3 ′), and the initial pressure PL / C of the torque converter is calculated. It will be easy.
[0035]
PL / C0 = (C1 × 2 × P3) + {(C3 × NE + C4 × N1) ² + (C5 × NE) ² }
= (C2 × 2 × P3) + {(C3 × NE + C4 × N1) ² + (C5 × NE) ² } (3 ′)
In addition, embodiment of this invention is not limited to the structure of the said embodiment. For example, the internal pressure detection device of the torque converter may be configured by providing a conductive passage in the housing of the torque converter instead of the conductive conduit of the external piping. This has the advantage that the internal pressure detecting device of the torque converter can be reduced in size and weight.
[0036]
A plurality of orifices may be provided on the upstream side and the downstream side of the pressure sensor. For example, two openings are connected in series, and the opening areas of the two upstream orifices are Aα1 and Aα2, and the opening areas of the two downstream orifices are Aβ1 and Aβ2. here,
1 / Aα ² = 1 / Aα1 ² + 1 / Aα2 ² (5)
1 / Aβ ² = 1 / Aβ1 ² + 1 / Aβ2 ² (6)
If Aα1, Aα2, Aβ1, and Aβ2 are set so as to satisfy the following, a circuit equivalent to the circuit shown in FIG. 1 can be obtained. In order to obtain a target opening area, a combination of a plurality of orifices has an advantage that the opening area can be adjusted more easily than a single orifice, so that the accuracy of the opening area can be further improved even if there are variations in parts. .
[0037]
In addition, as an embodiment of the present invention, a torque converter internal pressure detection method for use in torque converter lock-up clutch control has been described. However, the present invention is not limited to this mode, and other internal pressures are to be measured. It goes without saying that it can also be used as a method for detecting an internal pressure using only one pressure sensor for a pressure detection object such as a fluid coupling or a fluid retarder.
[Brief description of the drawings]
FIG. 1 is a hydraulic circuit diagram of a clutch hydraulic control valve of a lockup clutch according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of a lockup clutch portion.
FIG. 3 is a hydraulic circuit diagram of a clutch hydraulic control valve of a lockup clutch according to a conventional embodiment.
[Explanation of symbols]
2. Torque converter, 11 ... Pressure sensor, 12, 13 ... Orifice, 14, 15 ... Pipe line, 14a, 15a ... Branch point, 17 ... Conduction line.

Claims (3)

A device for detecting internal pressure in a fluid-mechanical power conversion device (2) that converts a fluid flow force into mechanical power and outputs it, such as a torque converter, a fluid coupling, and a fluid retarder,
A fluid flowing from the fluid inlet (14) into the fluid-mechanical power conversion device (2) is provided separately from the flow channel where the fluid works and flows out from the fluid outlet (15). connected fluid bypass passage to the bypass to the fluid outlet (15) and (17),
An inlet (14a) wherein the downstream bypass passage (17) outlet of (15a), respectively provided with inlet and outlet pressure loss means into an upstream side (12, 13) of said bypass passage (17),
Detecting an intermediate pressure between the input fluid pressure and the output fluid pressure generated between the inlet side pressure loss means (12) and the outlet side pressure loss means (13) to the device (2) , Pressure detection means (11) which uses the detected value of the intermediate pressure as an internal pressure in the device (2) ,
An internal pressure detecting device in a fluid-mechanical power conversion device (2) provided with The fluid bypass flow path (17) is bypassed from the flow path (14) on the fluid inlet side into the fluid-mechanical power conversion device (2), and is connected to the fluid outlet side in the fluid-mechanical power conversion device (2). A bypass conduction pipe (17) connected to the flow path of (15) ,
The inlet side pressure loss means (12) is a pressure loss throttle (12) provided on the downstream side of the bypass conducting pipe inlet (14a) ,
The outlet side pressure loss means (13) is a pressure loss throttle (13) provided on the upstream side of the bypass conduit outlet (15a) ,
Said pressure detecting means (11) is a pressure sensor disposed (11) between said diaphragm both pressure loss (12, 13),
The internal pressure detection device in the fluid-mechanical power conversion device (2) according to claim 1 .   The fluid according to claim 2, wherein a portion of the torque converter (2) bypasses the outside of the main body of the torque converter (2) from the pump blade side fluid inflow passage (14) and reaches the turbine blade side fluid outflow passage (15). -A torque converter comprising an internal pressure detecting device in the mechanical power conversion device (2).

Images