JPH0127299B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a hydraulic control device for an electrically controlled automatic transmission for a vehicle, and more particularly to a hydraulic control device that prevents a shock when a shift lever is manually shifted from a high speed range to a low speed range. [Prior Art] Conventionally, there is a D (drive) range that provides high speeds higher than 3rd gear, and a 3rd (third) range that provides 2nd gear where engine braking is effective, or an L (low) range that provides 1st gear. For example, if the shift lever is changed to the L range for deceleration while driving in the 4th gear of the D range, the automatic transmission will shift from the 4th gear to the 3rd gear, which is an intermediate gear. It is configured so that a downshift is performed directly to the second gear. [Problems to be solved by the invention] In the conventional automatic transmission configured as described above,
If you change the shift lever to L gear to decelerate while driving in 4th gear in D range, the automatic transmission will shift to 4th gear.
Since the downshift is performed directly from 3rd gear to 2nd gear by skipping 3rd gear, which is an intermediate gear, there is a large amount of friction in the frictional engagement elements, especially when switching from D range to L range while driving at high speed. There was a problem in that the durability of the vehicle would be impaired due to the force exerted on it, and that the engine would overrun.Furthermore, due to rapid deceleration, the vehicle would receive a large deceleration shock, resulting in poor feeling. The present invention prohibits deceleration that skips the intermediate gear if the vehicle speed exceeds a set value when there is a manual gear shift input that skips the intermediate gear, and decelerates once to the intermediate gear. The object of the present invention is to provide a hydraulic control device for an automatic transmission that can reduce deceleration shock and improve the durability of the friction material of the friction engagement device by decelerating the gear to a low gear after a predetermined period of time has elapsed. do. [Means for solving the problem] The hydraulic control device for an automatic transmission of the present invention includes a hydraulic pressure source 100, a pressure regulating valve 102 that regulates the hydraulic pressure supplied from the hydraulic source and outputs it as line pressure,
At least a high speed range that allows shifting to the highest speed of the automatic transmission and a low speed range that selects a low speed that is two steps lower than the highest speed of the automatic transmission can be manually switched to multiple oil passages. A manual valve 210 that selectively outputs line pressure to switch gear ranges, solenoid valves 320 and 330 that are controlled by an electric control circuit according to vehicle operating conditions such as vehicle speed and throttle opening, and the manual valve. inputs the line pressure applied through the solenoid valve and the solenoid pressure controlled by the solenoid valve, and selectively supplies and discharges the line pressure to the friction engagement element of the automatic transmission to control gear shift of the automatic transmission. In a hydraulic control device for an automatic transmission including a plurality of shift valves 220, 230, 240, a first shift valve that switches between a highest gear and an intermediate gear that is one step lower than the highest gear; a second shift valve for changing gears between a middle speed that is one step lower than the highest speed and a low speed that is two steps lower than the highest speed; a first solenoid valve that controls the first shift valve; A second solenoid valve that controls the second shift and the manual valve when switching from a high speed range to a low speed range,
A downshift in which the second solenoid valve is de-energized for a predetermined period of time to maintain the second shift valve at the middle speed position, and after a predetermined period of time, the second solenoid valve is energized to switch the second shift valve to the low speed position. a control means and a line pressure output when the manual valve is in the low speed range is supplied to the first shift valve 240;
First oil passage 3 for setting the shift valve to the middle gear position
Then, the line pressure output when the manual valve is in the low speed range is supplied to the second shift valve 230, and the second shift valve 230
A second oil passage 4 for setting the shift valve to the low gear position
and a control means 500 which is provided in the second oil passage and communicates the oil pressure in the second oil passage to the exhaust passage at a vehicle speed higher than or equal to a set vehicle speed. When switching from the high speed range to the low speed range, when the vehicle speed is above the set vehicle speed, the second solenoid valve is activated to shift from the highest speed to the middle speed for a predetermined period of time, and then downshift to the low speed. The present invention is characterized in that it is configured to directly downshift from the highest gear to the lower gear regardless of the operation of the second solenoid valve. [Operations and Effects of the Invention] The hydraulic control device for an automatic transmission of the present invention provides that when the manual valve is changed from the D range 4th gear to the L range for deceleration, while the vehicle is running at a high speed higher than the set speed. , the vehicle is first downshifted from 4th gear to 3rd gear and then downshifted to 2nd gear after a predetermined period of time has elapsed, reducing deceleration shock and improving the durability of the friction material of the friction engagement device. In addition, when the vehicle is running at a low speed below the set speed, the fourth speed is directly downshifted to the second speed, so the engine brake is effective and drivability is improved. In addition, even if the solenoid valve does not operate due to a failure in the electric control circuit, even if the manual valve is changed from D range 4th gear to L range for deceleration while the vehicle is running at a high speed higher than the set speed, the vehicle will not operate in 4th gear. Since the gear is shifted from 3rd gear to 1st gear after a predetermined time has elapsed, a sudden downshift from 4th gear directly to 1st gear can be prevented, preventing seizure, burnout, etc. of brakes and clutches. In addition to preventing this from occurring, when the vehicle starts at a speed lower than the set speed, the first speed can be obtained in the L range of the manual valve.
This has the effect of allowing a smooth start. Furthermore, by controlling the oil pressure of the oil passage using a governor valve that has hysteresis in operation when oil pressure is acting on the oil passage, the governor valve is set to the L range when the computer fails. Hunting can be prevented when driving using the shift from 1st speed to 3rd speed due to the operation of . [Embodiment] FIG. 1 is a schematic diagram showing an example of a planetary gear unit of a hydraulic four-speed automatic transmission with an overdrive device. The planetary gear unit of this automatic transmission includes a torque converter 10, an overdrive mechanism 20,
It is equipped with a planetary gear transmission mechanism 30 with three forward speeds and one reverse speed, and is controlled by a hydraulic circuit device as shown in FIG. Torque converter 10 is of a well-known type and includes a pump 55, a turbine 56, and a stator 57. Pump 55 is connected to an engine crankshaft 58, and turbine 56 is connected to a turbine shaft 59. The turbine shaft 59 forms the output shaft of the torque converter 10, which also serves as the input shaft of the overdrive mechanism 20, and is connected to a carrier 60 of a planetary gear system in the overdrive mechanism. A planetary pinion 64 rotatably supported by a carrier 60 is connected to a sun gear 61 and a ring gear 65.
It's meshing with each other. A multi-disc clutch 12 and a one-way clutch 13 are provided between the sun gear 61 and the carrier 60, and a multi-disc brake 19 is provided between the sun gear 61 and a housing or overdrive case 66 containing the overdrive mechanism. It is provided. The ring gear 65 of the overdrive mechanism 20 is connected to the input shaft 23 of a planetary gear transmission mechanism 30 with three forward speeds and one reverse speed. Input shaft 23 and intermediate shaft 29
A multi-plate clutch 24 is provided between the input shaft 23 and the sun gear shaft 80, and a multi-disc clutch 25 is provided between the input shaft 23 and the sun gear shaft 80. A multi-disc brake 26, a multi-disc brake 40 and a one-way clutch 41 are provided between the sun gear shaft 80 and the transmission case 68. The sun gear 82 provided on the sun gear shaft 80 includes a carrier 83, a planetary pinion 84 supported by the carrier, a ring gear 85 meshing with the pinion, another carrier 86, and a planetary pinion 87 supported by the carrier. , constitutes a two-row planetary gear system together with a ring gear 88 that meshes with the pinion. The ring gear 85 is connected to the intermediate shaft 29. Further, the carrier 83 in this planetary gear device is connected to a ring gear 88 in the other planetary gear device, and these carrier and ring gear are connected to an output shaft 89. Further, a multi-disc brake 27 and a one-way clutch 28 are provided between the carrier 86 and the transmission case 68 in the other planetary gear set. The planetary gear unit of such a hydraulic automatic transmission with an overdrive device engages or releases each clutch and brake according to the engine output and vehicle speed by a hydraulic circuit device, which will be explained in detail below. It is designed to have four forward speeds including drive (O/D) or one reverse speed through manual switching. The table shows the position of the transmission gear and the operating status of the clutch and brake.

[Table] Here, ◯ indicates that each clutch and brake are in an engaged state, and × indicates that they are in a released state. The above clutch and brake 12, 19, 2
A hydraulic circuit of a control device according to the present invention which selectively acts on gears 4, 25, 26, 27, and 40 to perform an automatic or manual gear shifting operation will be described based on an embodiment shown in FIG. The hydraulic circuit includes an oil reservoir 100, an oil pump 101, a pressure regulating valve 102, a second pressure regulating valve 103, a cutback valve 104, a cooler bypass valve 105, a pressure relief valve 106, a reverse clutch sequence valve 110, and a direct clutch control valve 120. , throttle valve 200, manual valve 210, 1-2
Shift valve 220, 2-3 shift valve 230, 3-4
A shift valve 240, an intermediate coast modulator valve 245 that adjusts the hydraulic pressure supplied to the brake 26, a low coast modulator valve 250 that adjusts the hydraulic pressure supplied to the brake 27, and smooth engagement of the clutch 24. an accumulator 260 for smooth engagement of the clutch 25, an accumulator 280 for smooth engagement of the brake 40, clutches 12, 24, 25, and brakes 26, 40,
Check valves 301, 302, 303, 304, 305, 3 that control the flow rate of pressure oil supplied to 27
06. A first solenoid valve 320 that is opened and closed by the output of an electric control circuit (computer) to be described later and controls the 2-3 shift valve, and a second solenoid that controls both the 1-2 shift valve and the 3-4 shift valve. valve 33
0, and a third solenoid valve 340 that controls the direct coupling clutch control valve 120, an oil passage that communicates between each valve, the clutch, and the hydraulic cylinder of the brake, and the manual valves 210 and 2-, which are the gist of the present related invention. 3 Connect the shift valve 230, 2-
A governor valve 500 that discharges the line pressure of the oil passage 4S, which is supplied with the line pressure that operates the 3rd shift valve 230 to the 1st and 2nd speeds, during high-speed operation at a set speed or higher.
It consists of Hydraulic oil pumped up from an oil reservoir 100 by an oil pump 101 is adjusted to a predetermined oil pressure (line pressure) by a pressure regulating valve 102 and then supplied to the oil path 1 .
Oil passage 1 connected to oil passage 1 via orifice 51
The pressure oil supplied to the second pressure regulating valve 103 via A is regulated to predetermined torque converter pressure, lubricating oil pressure, and cooler pressure according to the throttle pressure output from the throttle valve 200. The manual valve 210, which is connected to the oil passage, is connected to a shift lever installed on the driver's seat, and is manually operated to switch to P (park), P (reverse), N (neutral), or N (neutral) depending on the range of the shift lever. Move to D (drive), 3 (third), and L (low) positions. The table shows the communication state between oil passage 1 and oil passages 2 to 5 in the shift range of each shift lever. The mark ○ indicates a state in which line pressure is supplied through communication, and the mark x indicates a state in which the pressure is exhausted.

[Table] When the first solenoid valve 320 that controls the 2-3 shift valve 230 is not energized, the valve port 321 is closed and high level solenoid pressure (line When energized, the valve port 321 is opened and the pressure oil in the oil passage 2G is discharged from the oil drain port 323 to generate a low level solenoid pressure. The second solenoid valve 330 that controls the 1-2 shift valve 220 and the 3-4 shift valve 240 is closed to the valve port 3 when not energized.
31 is closed to generate high-level solenoid pressure in the oil passage 2F that communicates with the oil passage 2 via the orifice 332, and when energized, the valve 331 is opened and the oil drain port 3
The pressure oil in the oil passage 2F is discharged from 33 to generate a low level solenoid pressure. The table shows the relationship between energization (◯) and non-energization (x) of the solenoid valves 320 and 330 controlled by the electric control circuit described later in the table and the gear state of the automatic transmission. In addition, the gear shift number ( )
In some cases, the electric control circuit (computer) described later has failed and no output occurs, and the solenoid valve is de-energized.

[Table] A third solenoid 340 that controls the lock-up control valve 120 is provided in the illustrated upper oil chamber 121 of the lock-up valve 120, which communicates with the oil passage 1H that communicates with the oil passage 1 via an orifice 342. This solenoid valve 340 generates high-level solenoid pressure in the oil chamber 121 when not energized, and works with the spring 123 disposed behind the spool 121.
is pressed downward in the figure to position the spool 122 in the downward direction in the figure, and when energized, the pressure in the oil chamber 121 is evacuated and the solenoid pressure is reversed to a low level. The 1-2 shift valve 220 has a spring 22 on the left side in the figure.
When the solenoid valve 330 is de-energized and a high-level solenoid oil pressure is generated in the oil passage 2F, the high-level solenoid pressure enters the oil chamber 224 at the right end in the figure, and the oil pressure increases. As a result of the application of , the spool 222 is set to the left in the figure as shown in the lower half of FIG. 2, and is in the first speed position, the solenoid valve 330 is energized, the pressure in the oil passage 2F is exhausted, and the solenoid pressure is at a low level. At this time, the spool 222 is set to the right in the figure as shown in the upper half to obtain the second speed position. 2-
When the spool 232 of the 3rd shift valve 230 is located on the 3rd and 4th speed side, that is, in the 3rd and 4th speeds, the manual valve 210, oil passage 2, and 2-3 shift valve 2
Line pressure enters the left end oil chamber 223 from 30 and oil passage 2C, and the spool 222 is fixed on the second speed side (right side in the figure) regardless of the solenoid pressure. The 2-3 shift valve 230 has a spring 23 on the left side in the figure.
1, and when the solenoid valve 320 is energized and the oil passage 2G is at a low level solenoid pressure, the spool 232
is set to the right side in the figure by the action of the spring 231 to reach the first and second speed positions, and when the solenoid valve 320 is de-energized, high-level solenoid pressure is generated in the oil passage 2G and applied to the oil chamber 234. Due to the action of this solenoid pressure, the spool 232 is set to the left in the figure, and becomes the third and fourth speed positions. When line pressure is supplied to the oil passage 4 and to the left end oil chamber 233 via the orifice 235, the spool 232 moves to the right side in the drawing, which is the first and second speed side, regardless of the solenoid pressure. Locked. The 3-4 shift valve 240 includes a spool 242 with a spring 241 on one side, and the spool 232 of the 2-3 shift valve 230 is set to the first and second speed side (right side in the figure) and the oil passage 2 When line pressure is being supplied to the left end oil chamber 243, that is, in the first and second speeds, the line pressure is applied to the left end oil chamber 243 via the manual valve 210, oil passages 2, 2-3 shift valve 230, and oil passage 2B. , the spool 242 is set to the third speed side (to the right in the figure) regardless of the solenoid pressure. Also, when the spool 232 of the 2-3 shift valve 230 is set to the 3rd and 4th speed side (left side in the figure) and line pressure is supplied to the oil passage 3, that is, when the spool 232 of the 2-3 shift valve 230 is set to the 3rd and 4th speed side (left side in the figure), Also, line pressure is applied to the left end oil chamber 243 via the manual valve 210, oil passage 3, 2-3 shift valve 230, and oil passage 2B, and the spool 242 is applied to the third speed side (not shown) regardless of the solenoid pressure. right side). In the 1st and 4th gears when the solenoid valve 330 is de-energized, the right end oil chamber 24 passes through the oil passage 2F.
4, the spool 242 is set to the fourth speed side (left side in the figure) in the fourth speed. When the solenoid valve 330 is energized, that is, in the second and third speeds,
The solenoid pressure supplied to the right end oil chamber 244 via the oil path 2F is reversed to a low level, and the spool 24
2 is set to the third speed side (on the right side in the figure) by the force of the spring 241. In the throttle valve 200, a throttle plunger 201 strokes in accordance with the amount of depression of the accelerator pedal, and a spool 202 is moved via a spring 203 between the plunger 201 and a spool 202 on which a spring 204 is disposed on the back. The line pressure supplied from the throttle valve is regulated to a throttle pressure according to the throttle opening and output to the oil passage 9. When manual valve 210 is shifted to N range. As shown in the table, oil passage 1 does not communicate with any of oil passages 2 to 5, and as shown in the table, both first and second solenoid valves 320 and 330 are de-energized. Therefore, the spools of the 1-2 shift valve 220, the 2-3 shift valve 230, and the 3-4 shift valve 240 are all positioned to the right in the figure by the action of the spring. 3-4 to oil path 1 without going through manual valve 210
Only the clutch 12, which is in direct communication with the shift valve 240 via the oil passage 1J, is engaged. When manual valve 210 is shifted to D range. As shown in the table, hydraulic pressure is supplied to the oil passage 2, and line pressure is thereby supplied via the check valve 302 and the oil passage 2E, and the clutch 24 is engaged. For running in 1st speed, the solenoid valve 320 is operated as shown in the table.
is energized, solenoid valve 330 is de-energized, and 1-2
The spool 222 of the shift valve 220 is located on the left side in the figure, and is connected to oil passages 3E and 2 that communicate with the brakes 26 and 40.
A is an oil path 4C that is depressurized and connects to the brake 27.
Since hydraulic pressure is not supplied to brake 26,
40 and 27 are open. When the vehicle speed reaches a preset value, the solenoid valve 330 is energized by the output of the computer and the solenoid pressure applied to the oil chamber 224 is reversed to a low level.
The spool 222 of the 1-2 shift valve 220 moves to the right in the figure, and hydraulic pressure is supplied through oil path 2, 1-2 shift valve 220, oil path 2A, check valve 306, and oil path 2H, and the brake 40 is engaged. A shift to second gear occurs. Upshifting to 3rd gear is vehicle speed,
When the throttle opening etc. reach a predetermined value, the solenoid valve 320 is de-energized by the output of the computer,
The spool 232 of the 2-3 shift valve 230 moves to the left in the figure, and the oil passage 2, the 2-3 shift valve 230, the oil passage 2C, the check valve 303, the oil passage 2C, and the oil passage 2D.
Hydraulic pressure is supplied through the clutch 25, and the clutch 25 is engaged.
At the same time, the spool 222 of the 1-2 shift valve 220 is fixed to the left (toward the 2nd speed) in the figure by the line pressure supplied from the oil passage 2C to the left end oil chamber 223. As for the upshift valve to 4th gear, the solenoid valve 330 is de-energized by the output of the computer as described above, line pressure is supplied from the oil passage 2F to the right end oil chamber 244, and the spool 242 of the 3-4 shift valve is moved to the left in the figure. The oil passage 1J is evacuated and hydraulic pressure is supplied to the oil passage 1L, and the clutch 12 is released and the brake 19 is engaged. When manual valve 210 is in range 3. As shown in the table, line pressure is supplied to oil passage 3 in addition to oil passage 2. 1st and 3rd speeds are shifted in the same way as in the D range, but in 2nd speed, the line pressure supplied to the oil passage 3 is reduced to the 2-3 shift valve 23.
0, oil path 3A, 1-2 shift valve 220, oil path 3
B. The brake 26 is engaged via the intermediate coast modulator valve 245 and the oil passage 3C, and engine braking is applied by the action of the clutch 12 and brake 26. Also, via oil path 3 and oil path 2B, the left end oil chamber 2 of the 3-4 shift valve
Since line pressure is applied to 43 and the spool 242 is fixed to the left in the drawing, no shift to the fourth speed occurs. Furthermore, if the manual valve 210 is in the D position and a manual shift to D-3 is performed while driving in 4th gear, a downshift to 3rd gear is immediately performed by introducing line pressure to the left end oil chamber 243 as described above. . When manual valve 210 is in L range. In addition to the oil passages 2 and 3, line pressure is also supplied to the oil passage 4. The 2nd and 3rd speeds are the same as when the manual valve is in the 3rd range, and in the 4th speed, the line pressure supplied to the oil path 4 is 4A, low coast modulator valve 250, oil path 4B, 1-2
The brake 27 is engaged via the shift valve 220 and the oil passage 4C, and engine braking is applied by the action of the clutch 12 and brake 27. In addition, when manually shifting to the 3rd range while driving in the 3rd gear state, the computer output energizes the solenoid valve 320 when the speed has decelerated to the planned speed.
-2 causes a downshift. The manual valve 210 is shifted to the D, 3, and L ranges, line pressure is generated in the oil passage 2, and the 1-
When the 2-shift valve 220 is set to the 2nd speed side (right side in the figure), line pressure is generated in the oil passage 2A, and the lower end oil chamber 124 of the lock-up control valve 120 is
supplied to When the third solenoid valve 340 is energized by this line pressure and the oil pressure in the upper end oil chamber 121 is at a low level, the spool 122 of the lock-up control valve 120 is moved upward in the figure, and the oil passage 1A and oil passage 1D are connected. A lock-up clutch 50 provided within the torque converter 10
are engaged, and the torque converter 10 is in a directly connected state. If line pressure is not generated in the oil passage 2A, or even if line pressure is generated in the oil passage 2A, the solenoid valve 340 is de-energized and high-level solenoid pressure is generated in the oil chamber 121, the spring 123 or the spring 1
23 and the high level solenoid pressure, the spool 122 is positioned at the lower position in the figure. Spool 122
is located at the lower side in the figure, oil passage 1A is oil passage 1.
C, and the torque converter direct coupling clutch 50 is released. The solenoid valve 340 is energized by a computer, which will be described later, when the vehicle speed and throttle opening are greater than set values. FIG. 3 shows a state in which the governor valve 500, which is the gist of the present related invention, is installed when line pressure is being supplied from the manual valve 210 to the oil path 4 and sent to the oil path 4S via the orifice 235. It is a graph showing the relationship between the governor pressure characteristics of the oil passage 4S and the output shaft rotation speed. FIG. 4 shows a manual valve 210, a 2-3 shift valve 230, a first solenoid valve 320, and a governor valve 5.
00 and a circuit diagram of an oil passage connecting each. In FIG. 4, the spool 211 of the manual valve 210 is set to the D range as shown in the lower half of the figure, and while driving in the 4th speed, the spool 211 of the manual valve 210 is set to the L range as shown in the upper half of the figure by manual shift, and the oil is supplied to the oil path 2. When the line pressure that had been
The forces acting from the left and right sides shown in Figure 1 and their operations are as follows. (Output shaft rotation speed at set speed = N, governor pressure in oil passage 4S = P _4S , valve cross-sectional area = A ₁ , solenoid pressure in oil passage 2G = P _2G , spring force = F _S , line pressure = P _L ) (A) Output shaft rotation speed N _RPM or more → P _4S governor pressure is low level ) P _4S・A ₁ +F _S <P _2G・A ₁ (When P _2G = P _L when the first solenoid is OFF) Spool 231 is on the 3rd and 4th gear side (left side in the diagram)
is set to ) P _4S・A ₁ +F _S > P _2G・A ₁ (When the first solenoid is ON and P _2G is low level) The spool 231 is on the 1st and 2nd speed side (right side in the figure)
is set to At N _RPM or higher, the first, second, third, and fourth speeds can be selected depending on the operating state of the first solenoid. (B) Output shaft rotation speed O~N At _RPM , the governor pressure of P _4S is high level P _4S・A ₁ +F _S > P _2G・A ₁ (P _L = P _4S , P _L ≧ P _2G ) The spool 231 is 1st and 2nd speed side (right side in the diagram)
is set regardless of whether the first solenoid valve 320 is ON or OFF. The first and second solenoid valves 320 and 33 were damaged due to a failure of the electric control circuit (computer) to be described later.
When 0 becomes OFF (de-energized), (A) Output shaft rotation speed N _RPM or more → P _4S governor pressure is low level P _4S・A ₁ +F _S <P _2G・A ₁ (P _L = P _2G ) The spool 231 is set to the third and fourth speed sides. (B) Output shaft rotation speed O~N _RPM → P _4S governor pressure is at high level P _4S・A ₁ +F _S <P _2G・A ₁ (P _L = P _4S , P _L
=P _2G ) The spool 231 is set to the first and second speed sides. The first and second speeds or the third and fourth speeds are determined by changes in governor pressure. A shift signal output from the electric control circuit (CPU) described later in the table and energization of the solenoid valves 320 and 330 controlled by the shift signal (○);
The relationship between de-energization (×) and the gear shift position of the automatic transmission is shown.

【table】

[Table] The governor valve 500, which is the gist of the present related invention, is shown in the fifth column.
This is particularly shown in Figures 6 to 6. Governor valve 500 of this embodiment
is composed of a valve body 501, a cylinder 502, a valve body 503, and a spring 504. The valve body 501 has a tubular portion 505 that fits onto the drive shaft 50.
A tubular portion 506 into which the cylinder 502 is fitted is provided protruding from the outside in the radial direction, and a balance weight 507 is provided on the opposite side. The governor valve 500 is
A cylinder 502 is fitted into the tubular portion 506 of the valve body 501, and a spring 504 is attached to the cylinder 502.
A valve body 503 with a valve mounted on its back is attached. The inner diameter of the cylinder 502 has a large diameter portion 508 on the inside and a small diameter portion 509 on the outside, and the valve body 503 has lands 508A that slide on the inside and outside corresponding to the large diameter portion 508 and the small diameter portion 509, respectively. and 509A, and has a sleeve shape with a spherical protrusion 510 on the inner end surface and a hole 511 on the outer side in which the spring 504 is placed behind. An oil chamber 512 is formed between the land 508A and the land 509A, a lower end oil chamber 513 is formed inside the land 508A, an exhaust pressure port 514 is formed at the inside end of the cylinder large diameter portion 508, and an input oil port 515 is formed at a predetermined position in the middle. An oil drain port 516 of the oil chamber 512 is provided at a predetermined position in the inner side of the small diameter portion 509, and
Reference numeral 15 denotes an oil passage 4 that communicates the hydraulic control device, the automatic transmission block, the drive shaft 50, and the valve body 501.
I am contacting S. In the governor valve 500, when the output shaft rotation speed exceeds the set rotation speed N, the centrifugal force acting on the valve body 503 becomes stronger than the spring force of the spring 504.
The valve body 503 slides outward inside the cylinder 502, the input oil port 515 opens to the lower end oil chamber 513, and the oil passage 4S is in a state of being exhausted, and when the rotation speed is less than the set rotation speed N, the valve is closed. The centrifugal force acting on the body 503 is weak, and the valve body 503 is set closer to the inside.
The input oil port 515 is closed to the lower end oil chamber 513, and the oil passage 4S is not depressurized. In addition, in the governor valve 500 of this embodiment, there is a difference in area between the lands 508A and 509A of the valve body on the oil chamber 512 side end surfaces, so when line pressure is acting on the oil chamber 512,
An inward force is generated on the valve body 503 due to the pressure difference applied to both end faces. As a result, hysteresis occurs in the increase/decrease of the output shaft rotational speed while the line pressure is acting on the oil passage 4S. Figure 7 shows the relationship between the governor pressure characteristics of the oil passage 4S and the output shaft rotation speed when line pressure is applied, with N = N ₁ during speed increase and N = N ₂ during deceleration. Shown in the graph. Due to the above hysteresis, the first and second solenoid valves 320 and 33 may be damaged due to computer failure.
0 is OFF (de-energized), the manual valve is set to the L range, and hunting is prevented when driving using the first and third gear shifts caused by the operation of the governor valve 500. can do. First, in the case of (A) above, when the manual valve 210 is changed to the L range while the vehicle is running at a high speed higher than the set speed in the 4th gear in the D range. When a D-L manual shift is performed, the second solenoid valve 330 is first turned from OFF (de-energized) to ON (energized) by the computer output at the same time as the shift.
After a set time T programmed in the computer in advance has elapsed, the first solenoid valve 320 is turned from OFF to ON. Manual valve 2 in the table
Line pressure is simultaneously supplied to oil passages 3 and 4 from a state in which line pressure was being supplied from oil passage 10 only to oil passage 2. The governor valve 500, which is the gist of the present invention, operates to exhaust pressure. Oil passage 4S from oil passage 4 via orifice 235
The line pressure supplied to the governor valve 50 is discharged during high-speed running above a set speed, which is the gist of the present invention.
Since the low level governor pressure is supplied to the left end oil chamber 233 of the 2-3 shift valve, the spool 232 of the 2-3 shift valve is
It remains locked in the speed side (left side in the figure) position, and the line pressure supplied to the oil path 3 is applied to the spool 2.
32 is applied to the left end oil chamber 243 of the 3-4 shift valve via the 2-3 shift valve 230 set to the 3rd and 4th gear side (left side in the figure) and the oil passage 2B,
3-4 that was set to 4th gear (left side in the diagram)
The spool 242 of the shift valve is moved to the third speed side (to the right in the figure), and the third speed is established. solenoid valve 3
20 remains in a de-energized state for a time T programmed in advance by the computer, and during this time the spool 232 of the 2-3 shift valve is in the position to the 3rd and 4th gears (to the left in the figure), and 3rd gear is maintained. Ru. When time T has elapsed and the solenoid valve 320 is energized by the output of the computer, 2
- The line pressure applied to the right end oil chamber 234 of the 3-shift valve is reversed to a low level, and the spool 232 is moved to the 1st and 2nd gears by the force of the spring 231 (right side in the figure).
When the second solenoid valve 330 is energized at the same time as the DL manual shift, the oil passage 2
The solenoid pressure applied from F to the right end oil chamber 224 of the 1-2 shift valve is reversed to low level, and the 1-2 shift valve
Since the spool 222 of the shift valve is set to the second speed side (to the right in the figure), the second speed is set. As described above, the downshift from the fourth speed in the D range to the L range, that is, the downshift from the fourth speed to the second speed, is always performed at an intermediate gear stage when the vehicle is traveling at a high speed equal to or higher than the set speed. This is done after the set time T has elapsed in the third speed. Next, in case (B) above, when the manual valve 210 is changed to the L range while the vehicle is running at a low speed below the set speed in the 4th gear in the D range. When the DL manual shift is performed, the second solenoid valve 330 is turned from OFF (de-energized) to ON (energized) by the output of the computer as in the case of the DL manual shift during high-speed driving, and the set time T After , the first solenoid valve 320 turns from OFF to ON.
In the table, line pressure is supplied to oil passages 3 and 4 at the same time from the state in which line pressure was supplied from manual valve 210 only to oil passage 2.
The governor valve 500, which is the gist of the present invention, operates in a state where no pressure is discharged. Oil passage 4S from oil passage 4 via orifice 235
Since the line pressure supplied to the 2-3 shift valve is not exhausted by the governor valve 500, it becomes a high-level governor pressure and is supplied to the left end oil chamber 233 of the 2-3 shift valve, which is related to the operation of the first solenoid valve 320. Instead, lock the spool 232 of the 2-3 shift valve to the 1st and 2nd gear side (right side in the figure), and then
When ON (energized), the solenoid pressure applied from the oil passage 2F to the right end oil chamber 244 of the 1-2 shift valve is reversed to a low level, and the spool 2 of the 1-2 shift valve is reversed to a low level.
22 is set to the second speed side (right side in the figure). At the same time, from the oil passage 2F to the right end oil chamber 2 of the 3-4 speed valve.
The solenoid pressure applied to the solenoid 44 is also reversed to a low level, and the spool 242 of the 3-4 shift valve is set toward the third speed (to the right in the figure). As a result of the above, when driving at a low speed below the above-mentioned set speed, a downshift from the D range 4th speed to the L range, that is, a downshift from 4th speed to 2nd speed, is performed as an intermediate shift, similar to the conventional electrically controlled automatic transmission. In other words, it skips third gear and is directly downshifted from fourth gear to second gear. Next, a description will be given of the operation in the cases (A) and (B) above, that is, when the manual valve 210 is changed to the L range while the vehicle is running in the fourth speed in the D range at the time of a computer failure. The computer malfunctions and the first solenoid valve 32
0, when the second solenoid valve 330 is OFF (de-energized), 2
High-level solenoid pressure is applied to the right-end oil chamber 234 of the -3 shift valve, the right-end oil chamber 224 of the 1-2 shift valve, and the right-end oil chamber 244 of the 3-4 shift valve. In the case of (A) above, that is, when a DL manual shift is performed while driving at a high speed higher than the set speed,
Line pressure is simultaneously supplied to oil passage 3 and oil passage 4 in addition to oil passage 2, and governor valve 500, which is the gist of the present invention, operates to discharge pressure. Oil passage 4S from oil passage 4 via orifice 235
The line pressure supplied to is exhausted by the governor valve 500, and low level governor pressure is supplied to the left end oil chamber 233 of the 2-3 shift valve, so that the line pressure is discharged from the oil passage 2G to the right end oil chamber 234. Due to the high level of solenoid pressure being applied, the spool 232 of the 2-3 shift valve remains locked in the 3rd and 4th gear positions (to the left in the figure). The line pressure supplied to the oil path 3 is transferred to the 2-3 shift valve 230 and the oil path 2B.
The left end oil chamber 243 of the 3-4 shift valve 240 via
, the spool 2 of the 3-4 speed shift valve 240
42 moves to the third gear side (to the right in the diagram) and
Becomes faster. In the case of (B) above, that is, if the DL manual shift is performed while driving at a low speed below the set speed,
In addition to oil passage 2, line pressure is simultaneously supplied to oil passage 3 and oil passage 4, and governor valve 500, which is the gist of the present invention, operates in a state in which no pressure is discharged. Oil passage 4S from oil passage 4 via orifice 235
Since the line pressure supplied to the 2-3 shift valve is not exhausted by the governor valve 500, it becomes a high-level governor pressure and is supplied to the left end oil chamber 233 of the 2-3 shift valve, and the spool 232 of the 2-3 shift valve 1st, 2nd
Move quickly (to the right in the diagram). The spool 23
2 is set beside the first and second gears,
A 2-3 shift valve 230 and an oil passage 2 in which a spool 232 is set between the oil passage 2 and the 3rd and 4th gears.
The line pressure that was being applied to the left end oil chamber 223 of the 1-2 shift valve through B is cut off and reversed to the low level, so that the spool 222 of the 1-2 shift valve
is moved toward the first speed (to the left in the figure) by the high level solenoid pressure applied from the oil passage 2F to the right end oil chamber 224, and becomes the first speed. As a result of the above, the first solenoid valve 320 and the second solenoid valve 330 are disabled due to a computer failure.
When DL manual shift is performed when OFF. When driving at high speeds higher than the set speed, the switch will shift from 4th gear to 3rd gear.
When the vehicle is traveling at a low speed below the set speed, the gear is shifted from fourth gear to first gear. While the vehicle is running at low speed in the L range, it is in first gear, but when it is running at high speed, it is shifted from first gear to third gear at a set speed. An electric circuit (computer) that opens and closes the first and second solenoid valves 320 and 330 as shown in the table in accordance with the vehicle running state will be described with reference to FIG. The electric circuit includes a power supply device 420, a vehicle speed and throttle opening detection device, and solenoid valves 320, 3.
30, and a computer circuit 400 that leads to the driving of 30. The power supply device 420 is connected to a battery via a switch 421, and a position switch 422 mounted on a manual lever is used to set the D, 3, and L positions through a connection 520, and a power supply (constant voltage power supply device) 423 is connected through the connection 521. Conducted and connected from the sour supply 423 to the wire 52
3 to supply a constant voltage to each component of the computer 400. The computer circuit 400 includes a vehicle speed detection device 401, a waveform amplification shaping circuit 402, and a D-
A (digital-to-analog) conversion circuit 403, throttle position switch 413, throttle opening voltage generation circuit 414, 1-2 shift discrimination circuit 4
04, 2-3 shift discrimination circuit 406, 3-4 shift discrimination circuit 408, hysteresis circuit 405, 4
07,409, Solenoid valve 320 opening/closing determination circuit 410, Solenoid valve 330 opening/closing determining circuit 41
2. Solenoid valve 340 open/close decision circuit 424, N
-D shift signal generator 415, timer 411,
DL shift signal generator 418, timer 41
9, consisting of amplifiers 416, 417, 425, and solenoid valves 320, 330, 340. The vehicle speed detected by the vehicle speed detection device 401 becomes a sinusoidal waveform signal, which is shaped and amplified into a positive rectangular wave signal by the waveform amplification shaping circuit 402, and converted into a DC voltage signal according to the vehicle speed by the DA conversion circuit 403. Throttle position switch 4 detects the engine load condition.
13 is constituted by a variable resistor according to the throttle opening degree, and the signal according to the throttle opening degree is converted into a DC voltage by the throttle opening voltage generation circuit 414, and the 1-2 shift discrimination circuit 44, 2-3 respectively.
Shift discrimination circuit 406, 3-4 shift discrimination circuit 4
Enter 08. Each discrimination circuit compares the magnitude of the vehicle speed voltage signal and throttle opening voltage signal using, for example, a differential amplifier circuit, and sets the condition for 1-2 shift, 2-3 shift, or 3-4 shift. do.
Hysteresis circuits 405, 407, and 409 are for providing downshift conditions for 2-1 shift, 3-2 shift, and 4-3 shift, respectively.
Downshifting is performed at a slightly lower vehicle speed than the shift point at the time of upshifting, thereby preventing hunting in the shift range. The solenoid valve 320 opening/closing determination circuit 410 is connected to the D-
0 by the output of the L shift signal generator 418.
(OFF) or 1 (ON) output, and amplifier 4
16 to open and close the solenoid valve 320. The solenoid valve 330 opening/closing determination circuit 412 generates an output of 0 or 1 based on the outputs of the 1-2 shift discrimination circuit 404, the 3-4 shift discrimination circuit 408, and the output of the N-D shift signal generator via the timer 411, The solenoid valve 330 is opened and closed via the amplifier 417. Solenoid valve 34
The 0 opening/closing determining circuit 424 inputs the outputs of the 1-2 shift determining circuit 404, 2-3 shift determining circuit 406, and 3-4 determining circuit 408, and selects each pre-programmed gear stage while driving at 2nd speed or higher. When the vehicle speed and throttle opening are reached, the solenoid valve 340 is opened and closed via the amplifier 425. Next, an explanation will be given based on the embodiment shown in FIGS. 9 to 11. FIG. 9 is a partial hydraulic circuit diagram, and the configuration other than the gist is the same as the hydraulic circuit device shown in FIG. 2, and equivalent parts are designated by the same reference numerals. In this embodiment, instead of the governor valve 500, two
-3 Shift control valve 360 installed in oil passage 4S to control shift valve 230
By applying governor pressure according to the vehicle speed to the oil chamber of the shift control valve 360, the oil passage 4 is
The shift control valve 360 is operated so that the hydraulic pressure of S is discharged when traveling at high speeds exceeding a set speed, that is, when the governor pressure is above a predetermined value, and is not discharged when traveling at low speeds below the set speed, that is, when the governor pressure is below a predetermined value. and a governor valve 370 to control. The shift control valve 360 has a spring 3 at one end.
The spool 362 has a land 363 and a land 364, and the governor pressure is applied to the oil chamber 365 at the other end (lower side in the figure) through the oil passage 11 from the governor valve 370, and the land 36
When the governor pressure applied to the oil drain port 367 which is always open to the oil chamber 366 between the spool 3 and the land 364 and the oil chamber 365 exceeds the predetermined value, the spool 362
As shown in the left half, it has an oil port 368 of an oil passage 4S that opens into an oil chamber 366 when set upward in the figure. FIG. 10 shows the characteristics of the shift control pressure in the oil passage 4S controlled by the shift control valve 360, and FIG. 11 is a graph showing the characteristics of the governor pressure in the oil passage 11 controlled by the governor valve 370. If the vehicle speed exceeds the set speed, the governor valve 370
When the governor pressure applied to the oil chamber 365 through the oil passage 11 exceeds a predetermined value, the force due to the governor pressure overcomes the spring load of the spring 361 and
2 is set upward in the figure as shown in the left half, both an oil drain port 367 and an oil port 368 are opened in the oil chamber 366, and the shift control pressure of the oil path 4S is
8. Pressure is exhausted from the oil drain port 367 via the oil chamber 366. When the vehicle speed is below the set speed and the governor pressure applied to the oil chamber 365 is below a predetermined level, the force due to the governor pressure becomes smaller than the spring load of the spring 361, so the spool 362 is moved downward or downward as shown in the right half. It is set at an intermediate position, the oil port 368 does not open into the oil chamber 366, and the shift control pressure in the oil passage 4S is not discharged. As described above, the shift control valve 360 operates, and the oil pressure in the oil passage 4S is controlled to a low level when the vehicle is running at a high speed higher than the set speed of the vehicle, and to a high level when the vehicle is running at a low speed lower than the set speed of the vehicle. Next, the embodiment shown in FIG. 12 will be described. FIG. 12 is a partial hydraulic circuit diagram, and the configuration other than the gist is the same as the hydraulic circuit device shown in FIG. 2, and equivalent parts are designated by the same symbols. In this embodiment, instead of the governor valve 500, 2-
A solenoid valve 380 installed in the oil passage 4S to control the 3-shift valve 230 and a solenoid valve 380 that outputs an output when the vehicle speed rises above the set speed and the output from the vehicle speed detection device 401 rises above the set value. is turned on (energized), and when the vehicle speed falls below the set speed and the output from the vehicle speed detection device falls below the set value, no output occurs and the solenoid valve 380 is closed.
It also includes an electric circuit 390 that is turned OFF (de-energized). FIG. 13 is a graph showing the characteristics of the solenoid pressure in the oil passage 4S controlled by the solenoid valve 380. The ON/OFF operation of the solenoid valve is controlled as described above, and as in the embodiment of the second invention,
The oil pressure in the oil passage 4S is controlled to a low level when the vehicle is running at a high speed higher than a set speed, and to a high level when the vehicle is running at a low speed lower than a set speed. The hydraulic control device for an automatic transmission according to the present invention has the configuration as described above, and when the 2-3 shift valve operates from the 3rd and 4th gear side to the 1st and 2nd gear side, the 2-3 shift valve changes from the manual valve to the 2-3 shift valve. By controlling the oil pressure of the oil passage to which the line pressure applied to the predetermined oil chamber of the 3-shift valve is supplied, it is at a low level when traveling at high speeds above the set speed, and at a high level when traveling at low speeds below the set speed. , while the vehicle is running at a high speed higher than the set speed, D
From the 4th gear on the range, turn the manual valve to L for deceleration.
When changing to range, that is, when downshifting from 4th gear to 2nd gear for deceleration while driving at high speed, the shift signal sent from the electric control circuit to the solenoid valve is changed from 4th gear to 3rd gear to 2nd gear. By controlling the gears to be in the second gear, the gears are shifted to the third gear, which is an intermediate gear, for a predetermined period of time, and then the gears are shifted to the fourth gear in accordance with the shift signal.
speed→3rd gear→2nd gear, and when driving at low speeds, the gears are changed from 4th gear to 2nd gear using the same shifting operation as when driving at high speeds, so the shifting shock is small. 4th gear with good feeling → 2nd gear
In addition, when the solenoid valve does not operate due to a failure in the electric control circuit, the manual valve is shifted from D range 4th gear to L range for deceleration while driving at a high speed higher than the set speed as described above. When changing to 4th gear → 3rd gear
This has the effect of preventing seizure, burnout, etc. of the brakes and clutches that are likely to occur due to a sudden downshift, such as directly from 4th gear to 1st gear. Furthermore, while driving at low speeds, the gear changes from 4th to 1st using the same gear shifting operation as during high speed driving, so the powerful engine brake ensures sufficient deceleration effect required during low speed driving. can. In addition, by controlling the oil pressure in the oil passage using a governor valve that has hysteresis in its operation when oil pressure is acting on the oil passage, it is possible to set the oil pressure in the L range in the event of a failure of the computer and activate the governor valve. Hunting can be prevented when the vehicle is traveling using the shift from the first speed to the third speed due to the operation.

[Brief explanation of drawings]

Fig. 1 is a skeletal diagram of a vehicle automatic transmission, Fig. 2 is a circuit diagram of a hydraulic control device for an automatic transmission showing an embodiment of the present invention, and Fig. 3 is a graph showing governor pressure characteristics of the oil passage 4S. , FIG. 4 is a schematic partial circuit diagram of FIG. 2,
FIG. 5 is a sectional view showing the governor valve, FIG. 6 is a diagram of its installed state, FIG. 7 is a graph of the relationship between the change in governor pressure in the oil passage 4S and the output shaft rotation speed due to the operation of the governor valve 500, and FIG. 8 9 is a partial circuit diagram showing the second embodiment of the present invention, FIG. 10 is a graph showing the shift control pressure characteristics of the oil passage 4S, and FIG. 11 is a graph showing the shift control pressure characteristics of the oil passage 11. A graph showing the governor pressure characteristics, FIG. 12 is a partial circuit diagram showing the third embodiment of the present invention, and FIG. 13 is a diagram showing the oil passage 4S.
2 is a graph showing the solenoid pressure characteristics of FIG. In the figure, 102...regulator valve, 210...manual valve, 320,330,...340,380...
Solenoid valve, 500, 370...Governor valve, 36
0...Shift control valve, 220...1-2 shift valve, 230...2-3 shift valve, 240...3-4
shift valve.

Claims (1)

[Scope of Claims] 1. A hydraulic source, a pressure regulating valve that regulates the hydraulic pressure supplied from the hydraulic source and outputs it as line pressure, and a high-speed range that enables at least shifting to the highest speed of an automatic transmission. A manual valve that selectively outputs line pressure to multiple oil passages and switches between gear ranges by manually switching between the low speed range and the low speed range that selects a low speed that is two steps lower than the highest speed of the automatic transmission. and a solenoid valve that is controlled by an electric control circuit according to vehicle operating conditions such as vehicle speed and throttle opening, line pressure that is applied via the manual valve, and solenoid pressure that is controlled by the solenoid valve. A hydraulic control device for an automatic transmission comprising a plurality of shift valves that selectively supply and discharge line pressure to frictional engagement elements of the automatic transmission to control shifting of gears of the automatic transmission. a first shift valve for changing gears between a middle speed gear that is one step lower than the highest speed gear; and a first shift valve that changes gears between a middle speed gear that is one step lower than the highest speed gear and a low speed gear that is two steps lower than the highest speed gear; a second shift valve that performs switching; a first solenoid valve that controls the first shift valve; a second solenoid valve that controls the second shift valve; , the second solenoid valve is de-energized for a predetermined period of time to maintain the second shift valve at the middle speed position, and after the predetermined period of time has elapsed, the second solenoid valve is energized to switch the second shift valve to the low speed position. a shift control means; a first oil passage for supplying line pressure output when the manual valve is in a low speed range to a first shift valve and setting the first shift valve to a middle speed position; a second oil passage that supplies line pressure output during range operation to a second shift valve and sets the second shift valve to a low gear position; control means for communicating the hydraulic pressure of the vehicle to the discharge passage at a vehicle speed higher than a set vehicle speed, and when the manual valve is switched from a high speed range to a low speed range while the vehicle is running at the highest speed, the second solenoid valve The vehicle is operated to downshift from the highest gear to a middle gear for a predetermined period of time and then to a lower gear, and when the vehicle speed is below the set speed, the gear directly shifts from the highest gear to the lower gear regardless of the operation of the second solenoid valve. A hydraulic control device for an automatic transmission, characterized in that it is configured to shift. 2. The control means includes a governor body attached to the output shaft of the automatic transmission, a valve body disposed in the governor body so as to be slidable by centrifugal force, and a valve body disposed in the governor body connected to the second oil passage. A governor valve comprising an input oil port provided in the governor body and a discharge pressure port provided in the governor body, and when the vehicle speed exceeds a set speed, the valve body slides due to centrifugal force to connect the input oil port to the exhaust pressure port. A hydraulic control device for an automatic transmission according to claim 1, characterized in that it is comprised of: 3. The control means includes a governor valve that is attached to the output shaft of the automatic transmission and generates a governor pressure according to the rotation speed of the output shaft, and a governor valve that inputs the governor pressure and controls the second valve when the governor pressure is equal to or higher than a set value. 2. The hydraulic control device for an automatic transmission according to claim 1, further comprising a shift control valve that connects the oil passage to the discharge port. 4. The control means comprises an electromagnetic solenoid valve that inputs a vehicle speed signal and connects the second oil path to the discharge port when the vehicle speed signal is equal to or higher than a set value. The hydraulic control device for an automatic transmission according to item 1. 5. Hydraulic control for an automatic transmission according to claim 2, wherein the valve body is configured to cause the line pressure of the second oil passage to act against centrifugal force below a set vehicle speed. Device.