JP2879710B2 - Torque converter for outputting fluid / machine power and control method therefor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is applied to a power transmission device, in particular, a torque converter vehicle with a lock-up mechanism of a construction vehicle. A fluid with a torque converter with a multi-speed lock-up mechanism that prevents temporary disconnection and automatically performs lock-up and torque converter range switching according to the work load, and automatically performs optimal speed shift. The present invention relates to a torque converter that outputs mechanical power and a control method thereof.

[Conventional technology]

Conventionally, there are two types of power transmission devices for construction vehicles: a direct drive type with a mechanical clutch and a fluid drive type with a torque converter.The direct drive type stops the engine when an overload is applied, and reduces the shifting operability. Although it has the drawback of being poor, it has the advantage that power transmission efficiency is good and power can be transmitted in an impact manner. Further, the fluid drive type does not stop the engine even when an overload is applied, and the gear shifting operation is easy, but on the other hand, the power transmission efficiency is poor, and the power cannot be transmitted in an impact.
Of course, a torque converter with a lock-up function that has solved the drawbacks by taking advantage of the direct drive type and the fluid drive type has emerged. In recent years, construction vehicles such as bulldozers often have such a torque converter with a lock-up. Has become.

FIG. 8 shows a power transmission system of a tracked vehicle provided with the above-described torque converter with lock-up. The power of the output shaft 2 of the engine 1 is input to the torque converter 3. The pump 4 of the torque converter 3 is directly connected to the output shaft 2 of the engine 1, the stator 5 is mounted on a stator shaft 6 rotatable with respect to the torque converter output shaft 12, and the turbine 7 passes through the torque converter output shaft 12. And, it is connected to the input shaft 9 of the transmission 8 via the joint 13. Reference numeral 10 denotes a lock-up mechanism of the torque converter 3, and a clutch 11 of the lock-up mechanism 10 is pressed in a direction of a release position by a plurality of springs.
When the hydraulic pressure acts and pushes the working piston to put the clutch 11 into the “on” state, the torque converter output shaft 12 is directly connected to the output shaft 2 of the engine 1. The transmission 8 is a planetary gear wet multi-plate clutch type transmission, which includes a reverse clutch 14, a forward clutch 15, a first-speed clutch 16, a second-speed clutch 17, and a third-speed clutch 18, and an output shaft 19 of which moves forward and backward.
It rotates at a step speed. The output shaft 19 is transmitted to a horizontal shaft 22 via a pinion 20 and a bell gear 21. The horizontal shaft 22 is a pair of left and right steering clutches and brakes.
Through 23R, 24R, 23L, 24L a pair of left and right final reduction mechanisms 25R, 2
After being transmitted to 5L, these output shafts 26R, 26L are connected to sprockets 27R, 27L for driving a pair of left and right crawler belts.

[Problems to be solved by the invention]

However, in a conventional torque converter with a lock-up mechanism, power transmission at the time of switching from the torque converter range to lock-up or at the time of switching from lock-up to the torque converter is not necessarily performed smoothly. There is a drawback that it is not a lock-up drive, power is cut off, and it is not possible to absorb the impact of shifting up or down of the transmission, and the bulldozer shifts to the appropriate speed stage for load fluctuation during dosing However, it is necessary for the operator to select and execute this shift shift at the same time as switching between the torque converter and lockup. Not work efficiency Say there is a problem, also had reduced the work performance per fuel consumption due power loss of switching of the torque converter and lock-up.

In order to solve the above-mentioned conventional problems, the present invention maintains the performance of the torque converter vehicle, sets the lock-up mechanism to multi-stage shifting, shifts the gear in the torque converter range, locks up, and disconnects the power. Another object of the present invention is to provide a torque converter for outputting fluid / mechanical power and a control method for the same, in which a shift shock is reduced by preventing the shift, and further, an optimum speed stage and a lock-up range for a load are selected by an automatic shift. is there.

[Means for solving the problem]

According to a first aspect of the present invention, there is provided a torque converter for outputting fluid / mechanical power, wherein an input member and a turbine are coupled between a turbine of the torque converter and an output shaft of the torque converter, and the output member and the output shaft are coupled. A planetary gear mechanism having an input member and an output member, and selectively rotating or fixedly rotating the stator of the torque converter, so that either the fluid power or the mechanical power is applied to the output shaft. By selectively fixing the rotation of the power selection clutch to be output and the sun gear of the planetary gear mechanism, the output shaft outputs either low-speed fluid power or low-speed mechanical power reduced via the planetary gear mechanism. By selectively directly connecting the low-speed output clutch and the input member and the output member, high-speed fluid power and high-speed A high-speed output clutch that outputs any of the power, and a mechanical power selection clutch that inputs mechanical power to the input member by selectively coupling the input shaft and the input member of the torque converter. I do.

According to a second aspect of the present invention, in the torque converter for outputting fluid / mechanical power according to the first aspect, the input member is a link gear of a planetary gear mechanism coupled to a turbine of the torque converter, and the output member is an output of the torque converter. It is a planetary carrier of a planetary gear mechanism coupled to a shaft.

According to a third aspect of the present invention, there is provided a torque converter for outputting fluid / mechanical power according to the first aspect, wherein the input member of the planetary gear mechanism is connected to the turbine of the torque converter. A planetary carrier of the gear mechanism, wherein the output member is a ring gear of a planetary gear mechanism coupled to an output shaft of the torque converter.

According to a fourth aspect of the present invention, in the torque converter for outputting fluid / mechanical power according to the first aspect, the input member comprises a planetary carrier of a first stage planetary gear mechanism constituting a planetary gear mechanism coupled to a turbine of the torque converter. A link gear of the second stage planetary gear mechanism coupled to the planetary carrier, the output member being a link gear of the first stage planetary gear mechanism coupled to the output shaft of the torque converter, and a second gear coupled to the link gear. The low-speed output clutch, which is a planetary carrier of the two-stage planetary gear mechanism and selectively fixes the rotation of the sun gear of the planetary gear mechanism, is a first low-speed output clutch that selectively fixes the rotation of the sun gear of the first-stage planetary gear mechanism. And a second low-speed output clutch for selectively fixing the rotation of the sun gear of the second-stage planetary gear mechanism.

The method for controlling a torque converter that outputs fluid / mechanical power according to a fifth aspect of the present invention is a method for controlling a torque converter that outputs fluid power and mechanical power to an output shaft of a torque converter at low speed and high speed, respectively. 1. A method of controlling a torque converter that outputs fluid / mechanical power according to claim 1, wherein the fluid power is low, the mechanical power is low, and the torque is low.
It is switched in the order of transmission of high-speed fluid power and high-speed mechanical power, and according to the increase in torque acting on the output shaft of the torque converter, high-speed mechanical power, high-speed fluid power, low-speed mechanical power, and low-speed fluid power are switched. The transmission is switched in the transmission order, the low-speed and high-speed mechanical power transmissions are switched via the high-speed fluid power transmission, and the high-speed fluid power transmission is temporarily overlapped with the low-speed and high-speed mechanical power transmissions, and each power is transmitted. It is characterized in that there is no interruption of power at the output shaft of the torque converter when the transmission is switched, and mechanical power is output as main power.

[Action]

According to the first aspect, when the power selection clutch and the low-speed output clutch are engaged and the other clutches are disengaged, low-speed fluid power is output to the output shaft of the torque converter. If the mechanical power selection clutch and the low-speed output clutch or are turned on and the other clutches are turned off,
Low-speed mechanical power is output to the output shaft of the torque converter. If the power selection clutch and the high-speed output clutch are engaged and the other clutches are disengaged, high-speed fluid power is output to the output shaft of the torque converter. If the mechanical power selection clutch and the high-speed output clutch are engaged and the other clutches are disengaged, high-speed mechanical power is output to the output shaft of the torque converter.

According to a second aspect, in the first aspect, the planetary gear mechanism is decelerated when input from the link gear and output from the planetary carrier. According to the third aspect, the planetary gear mechanism is input from the planetary carrier in the first aspect. When output from the link gear, the speed is increased.
In the invention of the above, the input is made from the planetary carrier of the first stage planetary gear mechanism and the link gear of the second stage planetary gear mechanism,
If output from the link gear of the first stage planetary gear mechanism, reduction or speed increase can be selected.

According to the fifth aspect, the torque converter is switched in the order of low-speed fluid power, low-speed mechanical power, high-speed fluid power, and high-speed mechanical power in accordance with the decrease in the torque acting on the output shaft of the torque converter. In response to an increase in the torque acting on the output shaft, the transmission order is switched between high-speed mechanical power, high-speed fluid power, low-speed mechanical power, and low-speed fluid power. The high-speed fluid power transmission is temporarily overlapped with each of the low-speed and high-speed mechanical power transmissions so that there is no power interruption at the output shaft of the torque converter when each power transmission is switched, It can output mechanical power as main power.

〔Example〕

FIG. 1 is a skeleton diagram showing a torque converter for outputting a fluid / mechanical power of a two-stage shift of LOW and Hi, particularly a deceleration type, as a first embodiment of the present invention.
Reference numeral 30 denotes a torque converter, which includes a pump 32 rotated by an input shaft 31 and a turbine 33 provided on an output shaft 45 side.
And a stator 34 provided between the pump 32 and the turbine 33. The stator 34 is mounted on a stator shaft 35 rotatable with respect to an output shaft 45. A stator clutch 37 is provided between the stator shaft 35 and the housing 36. The torque converter 30 is provided with a two-stage deceleration lock-up mechanism 38, 39 is a lock-up clutch, 40 is a LOW clutch, and 41 is a Hi clutch. An output from the torque converter 30 is provided to the transmission via an output shaft 45, provided with a sun gear 43 and a planet gear 44.

Next, the operation of the torque converter with the two-stage shift lock-up mechanism will be described with reference to FIGS. It should be noted that the bold line in the figure indicates the transmission of power. FIG. 2 (A) shows the torque converter drive, in which the stator clutch 37 is turned on, and the power from the input shaft 31 is transmitted to the pump 32, the turbine 33, the ring gear 42, and the planetary gear 44 to output the output shaft. Output from 45. During this time, the lock-up clutch 39 and the Hi lock-up clutch 41 are in the “off” state. FIG. 2B shows the LOW lock-up drive from the torque converter drive described above.
When the Hi clutch 41 is "off" and the lock-up clutch 39 and the LOW clutch 40 are "on", power is transmitted to the output shaft 45 via the input shaft 31, the lock-up clutch 39 and the planetary gear 44. FIG. 2 (C) shows torque converter driving with the Hi clutch 41 engaged, the lock-up clutch 39 and the LOW clutch 40 being "off" and the stator clutch 37 and the Hi clutch 41 being "on". From the input shaft 31 to the pump 32, turbine 33, ring gear 4
2, transmitted to the output shaft 45. FIG. 2 (D) shows the Hi lock-up drive. When the stator clutch 37 and the LOW clutch 40 are "off" and the lock-up clutch 39 and the Hi clutch 41 are "on", the power is locked from the input shaft 31. The power is transmitted to the output shaft 45 via the up clutch 39, the ring gear 42, and the Hi clutch 41. Therefore, from the torque converter drive to the LOW and Hi shift lock-up drive, (A) → (B) → (C) →
The operation is switched in the order of (D).

FIG. 3 shows the above-mentioned two-speed shift lock-up switching in a transmission having a third speed, in which solid lines indicate lock-up drive, dotted lines indicate torque converter drive, and A1 to A3 indicate lock-up drive. And the switching point of the torque converter drive. B1 to B3 are LOW and Hi.
2 shows the lock-up shift point. However, if the load fluctuates from a heavy load state to a light load state during work traveling, this performance curve changes from (1st, torque converter drive) → A1 → (1s
t, LOW lockup drive) → B1 → (1st, Hi lockup drive) → A2 → (2nd, LOW lockup drive) → B2 →
(2nd, Hi lockup drive) → A3 → (3rd, LOW lockup drive) → B3 → (3rd, Hi lockup drive). At point A1, the torque converter range is switched to the lock-up range, and the lock-up at this time is in the LOW state. At the point B1, the mode is switched from 1st (low lock-up drive) to 1st (torque converter drive), and then to 1st (Hi lock-up drive). The above is the case where the load changes from a heavy load to a light load. However, when the load changes from a light load to a heavy load, the direction of the arrow is reversed. Then, this pattern is repeated during the work traveling.

FIG. 4 is a skeleton diagram showing a two-stage speed increasing type torque converter for outputting fluid / mechanical power according to a second embodiment of the present invention, wherein 46 is an input shaft, 47 is a torque converter, 48
Is a stator clutch, 49 is a two-stage speedup lockup mechanism,
50 is lock-up clutch, 51 is LOW clutch, 52 is Hi
A clutch, and a stator shaft 53, a ring gear 54, a sun gear 55, and a planetary gear 56 operated by each of these clutches.
Are output to the output shaft 57 via each gear when the clutch is engaged or disengaged. The procedure for switching between the torque converter drive and the LOW / Hi lock-up drive is the same as in the first embodiment.

FIG. 5 is a skeleton diagram showing a three-stage transmission type torque converter for outputting fluid / mechanical power according to a third embodiment of the present invention, wherein 58 is an input shaft, 59 is a torque converter, and 60 is a stator. A clutch, 61 is a three-stage speed-up lock-up mechanism, 62 is a lock-up clutch, 63 is a second low-speed clutch, 64 is a Hi clutch, and 65 is a first low-speed clutch, and a stator shaft operated by each of these clutches
66, a first ring gear 67, a second ring gear 68, a first sun gear 69, a second sun gear 70, a first planetary gear 71, and a second planetary gear 72 are provided. Is output to the output shaft 73. These torque converter drive and shift lock-up drive are the same as in the first embodiment described above.

With reference to FIG. 6, an automatic shift of a construction vehicle equipped with a multi-speed lock-up torque converter will be described. A construction vehicle such as a bulldozer repeatedly moves forward and backward while excavating and pushing soil during work traveling, but each time the load fluctuates between a light load and a heavy load. In accordance with this load change, the switching between the torque converter drive and the multi-speed lock-up drive and the transmission shift shift are automatically switched to perform proper and efficient work traveling. In FIG.
100 is a bulldozer body, 101 is a lower traveling body, 102 is a blade mounted on a front part, and 103 is a ripper device mounted on a rear part. Further, the power is transmitted to the left and right sprockets 109 of the lower traveling body via the engine 104, the torque converter 105 with the multi-speed transmission lock-up, the transmission 106, the steering device 107, and the final reduction device 108. Strain gauges or hydraulic gauges 110 and 111 are provided on the blade 102 and the ripper device 103 in order to detect the fluctuation of the work load of the bulldozer as a tendon force. The stress or oil pressure detected by the strain gauge 110, the hydraulic gauge 111, or the like is input to the controller 112, and is determined according to a preset value. Switching command,
And a speed gear command for the transmission 106 is output.
In this way, the torque converter 105
And the speed stage of the transmission 106 are automatically controlled. FIG. 7 shows a schematic flow of the automatic transmission. In addition, there are various means such as shoe slip control in addition to the above-mentioned means at the time of automatic shifting, but this embodiment shows an example of automatic shifting and is not limited thereto.

〔The invention's effect〕

Since the present invention is configured as described above, the following effects can be obtained.

(1) As the traction output is increased by the fluid drive of the torque converter and the traction force is reduced,
Switch to mechanical drive of two or more stage transmission with narrow speed range,
The running output can be improved according to the traction force, the efficiency can be improved, the power loss of the torque converter can be reduced, and the work performance can be improved.

(2) When shifting between low-speed and high-speed mechanical power transmissions, switching is performed via high-speed fluid power transmission, and the high-speed fluid power transmission is temporarily switched to low-speed and high-speed mechanical power transmissions. When the power transmission is switched, the output shaft of the torque converter is not disconnected when the power transmission is switched, and the mechanical power can be output as the main power, so that the rotation of the output shaft of the torque converter is disconnected during the shift shift. Without stopping the machine and losing speed, the work efficiency is improved.

[Brief description of the drawings]

1 to 3 show a first embodiment of the present invention, FIG. 1 is a skeleton diagram of a torque converter with a two-stage deceleration lock-up, and FIG. 2 shows a shift operation of the torque converter shown in FIG. Skeleton diagram, FIG. 3 is an explanatory diagram of shifting at the third speed of the transmission, FIG. 4 is a skeleton diagram of a torque converter with a two-stage speed-up lockup showing a second embodiment, and FIG. 5 is a three-stage showing a third embodiment. FIG. 6 is a schematic view of an automatic transmission for a construction vehicle having a torque converter according to the present invention, FIG. 7 is a flowchart of the same automatic shift as FIG. 6, and FIG. The figure is a power transmission skeleton diagram of a bulldozer showing the prior art. 30, 47, 59 torque converter 31, 46, 58 input shaft 35, 53 stator shaft 37, 48, 60 stator clutch 38 two-stage deceleration lock-up mechanism 39, 50, 62 Lock-up clutch 40, 51 LOW clutch 41, 52 Hi clutch 42, 54, 67, 68 Ring gear 43, 55, 69, 70 Sun gear 44, 56, 71, 72 Planet gear 45 57, 73… Output shaft 100… Bulldozer 101… Undercarriage 102… Blade 103… Ripper device 104… Engine 105… Torque converter 106… Transmission 107… Steering device 108… Final deceleration Device 109 Sprocket 110 Strain gauge 111 Hydraulic gauge 42 Controller

Continuation of front page (72) Inventor Teruo Nakahara 3-1-1 Ueno, Hirakata-shi, Osaka Komatsu Ltd. Osaka Plant (56) References JP-A-51-22970 (JP, A) JP-B-46-41724 (JP, B1)

Claims (5)

(57) [Claims] A turbine (33) of a torque converter (30, 47, 59) and an output shaft (4) of the torque converter (30, 47, 59).
Between the input member and the turbine (33), and between the output member and the output shaft (45, 57, 73). The planetary gear mechanism (38,49,61) having the above and the stator (34) of the torque converter (30,47,59) are selectively fixed or free-rotated, so that the output shaft (45,57,61). 73) Power selection clutch (37,48,60) that outputs either fluid power or mechanical power
And the sun gear (43, 55, 69, 7) of the planetary gear mechanism (38, 49, 61)
0), the output shaft (45,
57, 73) through a planetary gear mechanism (38, 49, 61) to output either low-speed fluid power reduced or low-speed mechanical power (40, 52, 63, 65); By selectively connecting input members and output members directly, the output shaft (4
5,57,73) high-speed output clutch (41,51,64) that outputs either high-speed fluid power or high-speed mechanical power without deceleration by planetary gear mechanism (38,49,61), and torque converter By selectively coupling the input shaft (31, 46, 58) of the (30, 47, 59) and the input member, a mechanical power selection clutch (36, 50, 62) for inputting mechanical power to the input member is provided. A torque converter for outputting fluid / mechanical power, comprising: 2. A torque converter for outputting fluid / mechanical power according to claim 1, wherein the input member is a link gear (42) of a planetary gear mechanism (38) coupled to a turbine (33) of the torque converter (30). Wherein the output member is a planetary carrier of a planetary gear mechanism (38) coupled to an output shaft (45) of the torque converter (30). 3. The torque converter according to claim 1, wherein the input member is a planetary carrier of a planetary gear mechanism (49) coupled to a turbine (33) of the torque converter (47). 2. The torque converter according to claim 1, wherein the output member is a ring gear (54) of a planetary gear mechanism (49) coupled to an output shaft (57) of the torque converter (47). . 4. A torque converter for outputting fluid / mechanical power according to claim 1, wherein the input member comprises a planetary gear mechanism (61) coupled to a turbine (33) of the torque converter (59). A planetary carrier of a planetary gear mechanism and a link gear of a second stage planetary gear mechanism coupled to the planetary carrier, the output member being a first stage planetary gear mechanism coupled to an output shaft (73) of a torque converter (59). And a planetary carrier of a second stage planetary gear mechanism coupled to the link gear (68), and selectively fixes the rotation of sun gears (69, 70) of the planetary gear mechanism (61). Low-speed output clutch (63, 65)
A first low-speed output clutch (65) for selectively fixing the rotation of the sun gear (69) of the stage planetary gear mechanism, and a second low-speed output for selectively fixing the rotation of the sun gear (70) of the second stage planetary gear mechanism. A torque converter that outputs fluid / mechanical power, which is a clutch (63). 5. At least one of claims 1 to 4, wherein the fluid power and the mechanical power can be output to the output shaft (45, 57, 73) of the torque converter (30, 47, 59) at low speed and high speed, respectively. 13. A method for controlling a torque converter for outputting fluid / mechanical power according to
7,59), according to the decrease in the torque acting on the output shaft (45,57,73), the transmission order is switched to low-speed fluid power, low-speed mechanical power, high-speed fluid power, and high-speed mechanical power. As the torque acting on the output shaft (45,57,73) of the converter (30,47,59) increases, the transmission order of high-speed mechanical power, high-speed fluid power, low-speed mechanical power, and low-speed fluid power The low-speed and high-speed mechanical power transmissions are switched via the high-speed fluid power transmission, and the high-speed fluid power transmission is temporarily overlapped with the low-speed and high-speed mechanical power transmissions.
Fluids / machines characterized in that the output shafts (45, 57, 73) of the torque converters (30, 47, 59) are not disconnected when switching between power transmissions, and mechanical power is output as main power. A method of controlling a torque converter that outputs power.