JP4048358B2 - Torque transmission system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a torque transmission system for transmitting a transmission torque corresponding to the torque command value to the torque transmitting device.
[0002]
[Prior art]
A recent four-wheel drive vehicle includes a torque transmission device in the middle of a propeller shaft that connects an engine and a rear wheel, for example, and is equipped with an ECU for driving and controlling the torque transmission device. The ECU determines a torque command value according to the situation, and generates an energization command value from the torque command value. Then, when the drive circuit energizes the torque transmission device with a current corresponding to the energization command value, the transmission torque according to the torque command value is transmitted to the rear wheels by the torque transmission device, and four-wheel drive traveling is performed.
[0003]
[Problems to be solved by the invention]
By the way, the above-described torque transmission device and ECU are usually manufactured separately and are electrically connected to each other after being mounted on an automobile. Here, the matching accuracy between the torque command value and the actually transmitted torque becomes a problem.
[0004]
However, conventionally, the torque transmission device and the ECU have been adjusted separately to satisfy the inspection standards. For this reason, in a state where the torque transmission device and the ECU are assembled, variations in individual accuracy are added, and it is difficult to improve the matching accuracy between the torque command value and the transmission torque.
[0005]
The present invention has been made in view of the above circumstances, as compared with the conventional, providing easy torque transmission system capable of improving the match accuracy between transmission torque actually transmitted torque command value Objective.
[0006]
[Means for Solving the Problems]
Torque transmission system according to the invention of claim 1 has been made in order to achieve the above object, is assembled in the middle of the four-wheel drive vehicle of the propeller shaft, and alterable torque transfer device torque propeller shaft is transmitted The torque command value is determined based on various information including the rotational speed difference between the front and rear wheels, and the energization command value is generated from the torque command value using the conversion data stored in advance, and the torque is determined according to the energization command value. A torque transmission system comprising an ECU for energizing a transmission device, wherein the torque transmission device transmits a transmission torque corresponding to a torque command value, and is a torque measuring device that can be attached to the torque transmission device before being assembled to the propeller shaft And a trimming device connectable to the ECU, wherein the trimming device replaces the torque command value determined based on various information. The torque command value determined in advance for adjustment is applied to the ECU, while the energization command value generated from the torque command value for adjustment is acquired from the ECU using the conversion data, and torque is transmitted according to the energization command value. A characteristic is that an actual measured value of torque transmitted by the apparatus is acquired from a torque measuring device, and conversion data is updated and stored in the ECU so that a deviation of the actual measured torque value from the torque command value becomes small .
[0007]
The invention of claim 2, Oite the torque transmission system of claim 1, the torque command value for adjusting the Ta, the current command value generated from the torque command value Ta by using the conversion data and I, When the measured value of torque that can be transmitted by the torque transmission device with respect to the torque command value Ta is defined as Tj, the trimming device determines that the energization command value I ′ obtained by I ′ = I · Ta / Tj is The conversion data is updated and stored in the ECU so as to be generated for the command value Ta.
[0009]
According to a third aspect of the present invention, in the torque transmission system according to the first or second aspect , the conversion data includes basic conversion data that cannot be updated and stored and correction conversion data that can be updated and stored, and the basic conversion data is used. A characteristic is that the energization command value is generated by adding the corrected energization command value generated from the torque command value using the correction conversion data to the basic energization command value generated from the torque command value.
[Action and effect of the invention]
<Invention of Claim 1>
According to the first aspect of the present invention, adjustment is performed while operating the entire torque transmission system including the ECU that generates an energization command value and energizes the torque transmission device according to the energization command value, and the torque transmission device. Therefore, as in the past, adjustments are made for each part of the torque transmission system, so that variations in accuracy are not added, and the torque command value matches the actual transmitted torque. Accuracy can be improved.
[0010]
<Invention of Claim 2>
In the invention of claim 2, the torque command value Ta, the energization command value I generated from the torque command value Ta using the conversion data, the actually measured transmission torque Tj, and the following equation:
I ′ = I · Ta / Tj
The conversion data is updated and stored so that the energization command value I ′ obtained from the above is generated for the torque command value Ta, and this update storage is repeated as necessary, whereby the torque command value and the actually measured transmission torque Can be converged to a predetermined value or less.
[0012]
<Invention of Claim 3 >
In the torque transmission system according to the third aspect, the correction conversion data among the conversion data can be updated and stored for adjustment, and the basic conversion data can be held as an initial value. Thereby, it can return to an initial state easily.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 shows a basic configuration of the torque transmission device 30.
The torque transmission device 30 includes a cylindrical outer case 33 with a bottom at one end, and an input portion 31 is configured by a shaft 33J extending from the center of the outer surface of the bottom wall 33T. A rear cover 35 is fitted and screwed inside the open end of the outer case 33, and an inner shaft 34 constituting the output portion 32 is liquid-tightly inserted into a through hole 35A formed at the center of the rear cover 35. Penetrates into the state.
[0014]
The inner shaft 34 is rotatably supported with respect to the outer case 33 in a state in which movement in the axial direction is restricted. One end of the inner shaft 34 extends to the inner back of the outer case 33 and the other end is Projecting outward from the outer case 33.
[0015]
A first cam disk 36 is rotatably fitted to the inner shaft 34 at a position near the rear cover 35 in the outer case 33, and a plurality of inner pilot clutches are provided on the outer peripheral surface of the first cam disk 36. The plate 37 is spline-fitted. Further, a plurality of outer pilot clutch plates 38 are spline-fitted near the rear cover 35 on the inner peripheral surface of the outer case 33, and the inner and outer pilot clutch plates 37, 38 are alternately arranged to be axial. Are facing each other. Further, a disk-shaped armature 49 is splined to the inner peripheral surface of the outer case 33 at a position where the group of pilot clutch plates 37 and 38 are sandwiched between the rear cover 35 and the rear cover 35. And, always, the inner and outer pilot clutch plates 37 and 38 can be separated from each other and freely rotate between the armature 49 and the rear cover 35.
[0016]
An electromagnetic coil 39 is arranged outside the outer case 33 so as to be adjacent to the rear cover 35. The electromagnetic coil 39 is accommodated in an annular groove formed in an annular yoke 39A, and the yoke 39A is rotatably supported on the rear cover 35 by a bearing (not shown). By exciting the electromagnetic coil 39, the pilot clutch plates 37 and 38 are drawn toward the rear cover 35 together with the armature 49, and the inner and outer pilot clutch plates 37 and 38 are frictionally engaged with each other. Further, as the magnetic force of the electromagnetic coil 39 is increased, the engagement of the pilot clutch plates 37 and 38 is deepened, and when the engagement is deepest, the pilot clutch plates 37 and 38 are integrally coupled so-called a directly connected state. . The first cam disk 36 receives the rotational torque from the outer case 33 and rotates by frictional engagement or direct coupling of the pilot clutch plates 37 and 38 described above.
[0017]
V-shaped recesses 40 are formed at a plurality of locations along the circumferential direction on the surface of the first cam disk 36 facing the back side (the left side in FIG. 1) of the outer case 33. 2A shows a cross-sectional view of the V-shaped recess 40 as seen from the radial direction of the first cam disk 36. As shown in FIG. 2A, the V-shaped recess 40 is formed in the width direction (FIG. 2). It is depressed into a V shape so as to gradually become deeper toward the center of (A) (vertical direction). A second cam disk 41 is spline-fitted to the outer surface of the inner shaft 34 on the back side (left side in FIGS. 1 and 2A) from the first cam disk 36, and the second cam. The disk 41 is formed with a V-shaped recess 42 symmetrically with the V-shaped recess 40 of the first cam disk 36. When the cam ball 43 is sandwiched and held between the V-shaped recesses 40 and 42 and the first cam disk 36 is rotated, the cam ball 43 is inserted into the V-shaped recess as shown in FIG. A force is generated in a direction to move the first and second cam disks 36 and 41 away from each other by moving to a shallow position at 40 and 42. Further, the first cam disk 36 is restricted from moving in the axial direction by an abutting portion (not shown), so that when the first cam disk 36 rotates, the second cam disk 41 is moved to the outer case. It is pushed to the back side of 33 and moves.
[0018]
As shown in FIG. 1, a plurality of inner main clutch plates 44 are spline-fitted to the outer peripheral surface of the inner shaft 34 on the back side of the outer case 33 from the second cam disc 41 and a plurality of outer main clutches. The plate 45 is spline fitted to the inner peripheral surface of the outer case 33. The inner and outer main clutch plates 44 and 45 are arranged alternately and face each other in the axial direction, and the inner and outer main clutch plates 44 and 45 are always separated from each other and freely rotatable. It is in a state. As described above, the inner and outer main clutch plates 44 and 45 are pushed to the bottom wall 33T side of the outer case 33 by the second cam disc 41 moved due to the magnetic force of the electromagnetic coil 39, and are mutually connected. Friction is engaged, and torque from the outer case 33 to the inner shaft 34 is transmitted through the main clutch plates 44 and 45. Further, due to the increase in the magnetic force of the electromagnetic coil 39, the pressing force of the second cam disk 41 is increased, and the frictional engagement between the main clutch plates 44 and 45 is deepened. When the engagement is deepest, the main clutch plates 44 and 45 are integrally connected to each other so-called directly connected state.
[0019]
In summary, in the torque transmission device 30, the input unit 31 and the output unit 32 are in a disconnected state in which the input unit 31 and the output unit 32 can freely rotate, and the input unit 31 and the output unit 32 while allowing a rotation difference. It is possible to change to a state in which a predetermined torque is transmitted from 31 to the output unit 32 and a direct connection state in which the input unit 31 and the output unit 32 are completely coupled.
[0020]
The torque transmission device 30 described above is assembled in the middle of a propeller shaft of an automobile, for example, as shown in FIG. A trans-axle 11 is provided adjacent to the engine 10 on the front side (left side in FIG. 3) of the automobile, and a transmission, a transfer, and a front differential 12 are assembled integrally with the trans-askle 11. The driving force of the engine 10 is transmitted to the front wheel driven shafts 13 and 13 through the transmission of the transaxle 11 and the front differential 12 to drive the front wheels 14 and 14.
[0021]
Further, the transmission and the front end portion of the front propeller shaft 20 are gear-connected by the transfer of the transaxle 11. The rear end portion of the front propeller shaft 20 is positioned at the middle portion in the front-rear direction of the automobile and is fixed to the input portion 31 (see FIG. 1) of the torque transmission device 30.
[0022]
A rear propeller shaft 21 extends on an extension line of the front propeller shaft 20 with the torque transmission device 30 interposed therebetween, and a front end portion of the rear propeller shaft 21 is an output portion 32 of the torque transmission device 30 (see FIG. 1). ). Further, the rear end portion of the rear propeller shaft 21 is connected to the rear differential 17, and the rear wheels 15, 15 are attached to the front ends of the rear wheel driven shafts 16, 16 extending from the rear differential 17 in both the left and right directions. It has been. Accordingly, the rear wheels 15 and 15 rotate in conjunction with the output unit 32 of the torque transmission device 30.
[0023]
The torque transmission device 30 is driven by the ECU 50, and the ECU 50 and the torque transmission device 30 constitute a torque transmission system 90 according to the present invention. As shown in FIG. 4, for example, a ROM 71, a RAM 72, an EEPROM 73, and a drive circuit 74 are connected to the CPU 70 provided in the ECU 50. Further, the ECU 50 can be switched between a normal mode and an adjustment mode by a trimming mode signal from a trimming device described later, for example. Further, the ECU 50 detects a throttle sensor 60 for detecting the throttle opening m, and the rotational speeds N1 and N2 of the front wheels 14 and 14 and the rotational speeds N3 and N4 of the rear wheels 15 and 15 as shown in FIG. Each output line of the rotational speed sensor 61 is connected.
[0024]
In the normal mode in which the trimming mode signal is not input to the ECU 50, the torque command value Ta is determined based on various information (detection signals) taken from the sensors 60 and 61. Specifically, in the normal mode, as shown in the block diagram of FIG. 5, the throttle opening degree m and the rotational speeds N1 to N4 of the front and rear wheels 14 and 15 are taken into the ECU 50, and the vehicle speed V and the front and rear wheels 14, A rotational speed difference ΔN of 15 is calculated. Here, the vehicle speed V is obtained as an average value of the rotational speeds N3 and N4 of the rear wheels 15 and 15, which are driven wheels with less slip, for example as shown in the following equation (1). On the other hand, the rotational speed difference ΔN is obtained by calculating the sum of the rotational speeds N3 and N4 of the two rear wheels 15 and 15 from the sum of the rotational speeds N1 and N2 of the two front wheels 14 and 14, as shown in the following equation (2). It is calculated by subtracting 2 minutes.
[0025]
V = (N3 + N4) / 2 (1)
[0026]
ΔN = (N1 + N2-N3-N4) / 2 (2)
[0027]
Then, the pre-torque Tp and the rotational difference torque Tn are determined from the vehicle speed V and the rotational speed difference ΔN and the throttle opening m. Specifically, the pre-torque Tp corresponding to the throttle opening m and the vehicle speed V is calculated using the data map D1 stored in the ROM 71. In addition, the rotational difference torque Tn corresponding to the rotational speed difference ΔN and the vehicle speed V is calculated using another data map D2.
The torque command value Ta according to the present invention is calculated as the sum of the pre-torque Tp and the rotation differential torque Tn.
[0028]
Here, the rewritable non-volatile memory (EEPROM 73) corresponds to the current command value I (the “energization command value” according to the present invention) flowing from the drive circuit 74 to the electromagnetic coil 39 in correspondence with the torque command value Ta. ) Is stored as a data map D3. Then, a current command value I is generated from the torque command value Ta using a data group (corresponding to “conversion data” according to the present invention) stored in the data map D3 and applied to the drive circuit 74. Then, the drive circuit 74 applies a pulse voltage to the electromagnetic coil 39 so that a current corresponding to the current command value I flows through the electromagnetic coil 39. As a result, the electromagnetic coil 39 is excited and the transmission torque Tj corresponding to the torque command value Ta is transmitted from the input unit 31 to the output unit 32 of the torque transmission device 30.
[0029]
The current flowing from the drive circuit 74 to the electromagnetic coil 39 is detected by the current sensor 62 and fed back to the CPU 70 via the A / D converter 75. Based on this feedback signal, PI control is performed so that currents corresponding to the current command value I flow through the electromagnetic coil 39.
[0030]
The above is the configuration related to data processing in the normal mode. When the ECU 50 is set to the adjustment mode by inputting the trimming mode signal, the torque command value Ta can be taken in from the outside. Specifically, as shown in FIG. 6, when the trimming device 80 is connected to the ECU 50 and a trimming mode signal is input to enter the adjustment mode, the adjustment program stored in the ROM 71 and the trimming device 80 are not shown. Together with the adjustment program stored in the ROM. Then, the torque command value Ta for adjustment stored in the ROM of the trimming device 80 is taken into the ECU 50 as shown in FIG. 7, and the current command value I is determined based on this torque command value Ta. Based on the current command value I, the drive circuit 74 drives the torque transmission device 30 as described above.
[0031]
Here, the trimming device 80 is connected to a torque measuring device 81 for measuring the transmission torque Tj transmitted by the torque transmission device 30 as shown in FIG. The trimming device 80 takes in the current command value I generated by the ECU 50, obtains a current command value I ′ for correction from the following equation (3) by calculation processing, and outputs it to the ECU 50.
[0032]
I ′ = I · Ta / Tj (3)
[0033]
When the ECU 50 receives the correction current command value I ′ in the adjustment mode, when the same torque command value Ta is determined next time, the ECU 50 determines the current command value I ′ with respect to the torque command value Ta. The contents of the data map D3 are updated and stored so as to be generated. As a result, the deviation between the determined torque command value Ta and the actually measured transmission torque Tj can be adjusted to be reduced.
[0034]
The adjustment program of the ECU 50 and the trimming device 80 repeats the update storage of the data map D3 until the deviation between the torque command value Ta and the actually measured transmission torque Tj becomes smaller than a predetermined value. Thereby, the deviation between the torque command value Ta and the transmission torque Tj can be converged to a predetermined value or less.
[0035]
When the deviation between the torque command value Ta and the transmission torque Tj becomes smaller than a predetermined value, the torque command value Ta is changed to another value and the same operation is repeated. Thereby, with respect to all the torque command values Ta which can be determined, it adjusts so that the deviation with the measured transmission torque Tj may become below a predetermined value.
[0036]
The configuration of the present embodiment is as described above. A predetermined torque transmission device 30 and the ECU 50 are connected to complete the torque transmission system 90, and the adjustment described above is performed on the torque transmission system 90.
[0037]
As described above, according to the present embodiment, the entire torque transmission system 90 including the part (CPU 70 or the like) that generates the current command value I (energization command value), the drive circuit 74, and the torque transmission device 30 is provided. Since adjustment is performed while operating, it is possible to prevent a situation in which variations in accuracy are added by adjusting each part of the torque transmission system as in the past, and the torque command value Ta is actually It is possible to improve the matching accuracy with the transmitted torque Tj.
[0038]
<Other embodiments>
The present invention is not limited to the above-described embodiment. For example, the embodiments described below are also included in the technical scope of the present invention, and various other than the following can be made without departing from the scope of the invention. It can be implemented by changing.
(1) The torque transmission system of the above embodiment is modified to use a data map having parameters relating to the temperature of the torque transmission device 30 as shown in FIG. The present invention may be applied to a torque transmission system that determines the current command value I from the above. In this case, the torque transmission system and the adjustment device may be housed in a temperature-controlled room, and the data map may be updated and stored for each temperature while changing the temperature of the torque transmission device 30.
[0039]
(2) As a data map for determining the current command value I from the torque command value Ta in the embodiment, a first data map storing a basic conversion data group, and a second data map storing a correction conversion data group The current command value I may be obtained by adding the basic data generated from the torque command value Ta using the first data map and the auxiliary data generated using the second data map. In addition, in a state before the adjustment, the energization command value I can be generated from the torque command value Ta using only the basic conversion data stored in the first data map, and the correction conversion data is stored in the second data map by the adjustment. It may be. Thereby, it can return to an initial state easily.
[0040]
(3) In the said embodiment, although the electricity supply command value which concerns on this invention was the current command value I, a voltage command value may be sufficient.
[Brief description of the drawings]
FIG. 1 is a side sectional view showing a basic configuration of a torque transmission device according to an embodiment of the present invention. FIG. 2 is a sectional view of a V-shaped recess. FIG. 3 is a concept showing a drive system of an automobile to which the torque transmission device is attached. FIG. 4 is a block diagram showing a configuration of an ECU. FIG. 5 is a block diagram showing a configuration of data processing in a normal mode. FIG. 6 is a block diagram showing a state in which a trimming device for adjustment is connected. FIG. 8 is a block diagram showing a data processing configuration according to the first modification.
DESCRIPTION OF SYMBOLS 30 ... Torque transmission apparatus 31 ... Input part 32 ... Output part 74 ... Drive circuit 90 ... Torque transmission system I ... Current command value (energization command value)
I '... Current command value (energization command value)
Ta ... Torque command value Tj ... Transmission torque Tp ... Pre-torque

Claims (3)

A torque transmission device assembled in the middle of a propeller shaft of a four-wheel drive vehicle and capable of changing a torque transmitted by the propeller shaft;
A torque command value is determined based on various information including the rotational speed difference between the front and rear wheels, and an energization command value is generated from the torque command value using conversion data stored in advance, and the energization command value is determined according to the energization command value. A torque transmission system comprising an ECU for energizing the torque transmission device, wherein the torque transmission device transmits a transmission torque according to the torque command value;
A torque measuring device that can be attached to the torque transmission device before assembly to the propeller shaft, and a trimming device that can be connected to the ECU;
The trimming device applies a torque command value determined in advance for adjustment to the ECU instead of a torque command value determined based on the various information, while the adjustment data uses the conversion data. An energization command value generated from the command value is obtained from the ECU, and an actual value of torque transmitted by the torque transmission device according to the energization command value is obtained from the torque measuring device, and the torque relative to the torque command value is obtained. A torque transmission system in which the ECU is updated and stored with the conversion data so that a deviation of an actual measurement value of the ECU is small . The torque command value for adjustment is Ta, the energization command value generated from the torque command value Ta using the conversion data is I, and the torque that can be transmitted by the torque transmission device to the torque command value Ta. When the measured value is Tj, the trimming device
I ′ = I · Ta / Tj
The torque transmission system is characterized in that the conversion data is updated and stored in the ECU so that the energization command value I ′ obtained in (1) is generated for the torque command value Ta . The conversion data includes basic conversion data that cannot be updated and stored and correction conversion data that can be updated and stored, and the correction conversion data is added to the basic energization command value generated from the torque command value using the basic conversion data. The torque transmission system according to claim 1 or 2 , wherein the energization command value is generated by adding a corrected energization command value generated from the torque command value .

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