JP2764190B2 - Shift control device for continuously variable transmission - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift control device for a continuously variable transmission, and in particular, converts a driving force of an internal combustion engine according to a traveling state of a vehicle by a required speed ratio and extracts the driving force. And a continuously variable transmission having a hydraulic clutch that is disengaged by supplying and discharging hydraulic pressure so as to maintain the output driving force, wherein the continuously variable transmission has a hydraulic supply stop mechanism for stopping supply of hydraulic pressure to the hydraulic clutch. A shift control device.

2. Description of the Related Art In a vehicle such as an automobile, a transmission is provided in order to appropriately extract a driving force generated by an internal combustion engine according to a traveling state. The transmission includes a manual transmission in which the driver manually converts the driving force of the internal combustion engine to a required gear ratio according to the traveling state and takes out the driving force of the internal combustion engine automatically according to the traveling state. In addition, there is an automatic, that is, a continuously variable transmission or the like that converts and takes out in a stepless manner.

As a continuously variable transmission, there is one disclosed in JP-A-61-109921. The synchronous meshing device for a transmission disclosed in this publication includes an axial end face of a hub that slidably holds a shift operation sleeve, and an opposing face of each of advancing side and retreating side synchro rings facing the hub. A semi-spherical projection that is positioned so that the chamfers of the splines of the sleeve and the synchro ring are always on the same line during constant elastic engagement, and a detent having an inclined surface in the synchronous engagement direction. Has formed.

Then, the shift operation is smoothly performed, and the operability and shift feeling at the time of starting or retreating are improved.

Another example is disclosed in JP-A-1-193416. The control device for a dry clutch for a vehicle disclosed in this publication includes a detecting means for detecting a clutch position, a rotational speed detecting means for detecting a rotational speed on a clutch output side, and a correction for inputting signals from these detecting means. A correction amount calculating unit that calculates a correction amount based on the previous and current positions of the clutch position when the rotational speed of the clutch output side rises from substantially zero, and controls the clutch for clutch disconnection control. The position and the target clutch position for half-clutch control are corrected by the correction amount.

The correction absorbs the wear and variation of the clutch at every start control, thereby improving the accuracy of the start control.

Further, a shift mechanism of the continuously variable transmission is disclosed in
JP-A-144338, JP-A-57-144339, JP-A-58-144339
156754, JP-A-60-159452, JP-A-60-15
Most of the publications such as 9453 employ a mechanical shift mechanism.

[Problems to be Solved by the Invention] By the way, in a conventional shift control device of a continuously variable transmission, a forward / backward switching mechanism for switching, for example, a forward / backward engagement state of the continuously variable transmission by a shift mechanism is mechanically switched. There is something to work. In the case of such a mechanical shift mechanism, there is a problem that a smooth shift operation cannot be obtained.

Therefore, a manual shift valve is switched by a shift mechanism to supply / discharge hydraulic pressure to a shift servo valve, and a forward / backward switching mechanism for switching, for example, a forward / reverse engagement state of the continuously variable transmission is operated by the shift servo valve. There is something. According to such a hydraulic servo type shift mechanism, the shift operation can be performed smoothly.

However, when the shift operation from the parking range P to the reverse range R or from the neutral range N to the drive range D is started, as shown by a broken line in FIG. However, there is a disadvantage that the clutch pressure at the time of shifting does not increase until the gear is switched by the switching member, and the responsiveness at the time of the shifting operation is poor.

[Object of the Invention] Accordingly, an object of the present invention is to switch the forward / reverse engagement state of a continuously variable transmission having a hydraulic clutch by a forward gear, a reverse gear, and a switching member between the two gears in order to eliminate the above-mentioned disadvantages. A forward / backward switching mechanism is provided, and a shift servo valve that supplies and discharges hydraulic pressure to switch the forward / backward switching mechanism is provided. A switching mechanism is used to supply and discharge hydraulic pressure to the hydraulic clutch and supply hydraulic pressure to the shift servo valve. A manual shift valve is provided, and a hydraulic supply stop mechanism for stopping the supply of hydraulic pressure to the hydraulic clutch is continuously variable. After a shift operation by the shift mechanism of the transmission, the bearing of one of the forward gear or the reverse gear is used. Until the meshing part formed on the outer periphery and the end of the switching member mesh with each other,
A continuously variable transmission that can impress the groove portion communicating with the hydraulic clutch to allow supply of hydraulic pressure to the hydraulic clutch, perform the shift operation more smoothly and reliably, and improve safety during shift operation. To realize the shift control device.

Means for Solving the Problems In order to achieve this object, the present invention relates to a driving force that converts and extracts a driving force of an internal combustion engine in a stepless manner according to a traveling state of a vehicle according to a required gear ratio and outputs the driving force. In a continuously variable transmission having a hydraulic clutch that is engaged and disengaged by supplying and discharging hydraulic pressure in order to continue the operation, the forward and backward engagement state of the continuously variable transmission is controlled by a forward gear, a reverse gear, and a switching member between the two gears. A forward / backward switching mechanism for switching, a shift servo valve for supplying / discharging hydraulic pressure for switching the forward / backward switching mechanism is provided, and a hydraulic pressure is supplied / discharged to / from the hydraulic clutch and a hydraulic pressure is supplied to the shift servo valve. The continuously variable transmission includes a manual shift valve that is switched by a shift mechanism of the continuously variable transmission, and a hydraulic supply stop mechanism that stops supplying hydraulic pressure to a hydraulic clutch. A groove communicating with the hydraulic clutch during a period from after the shift operation by the shift mechanism until the meshing portion formed on the outer periphery of the bearing of one of the forward gear and the reverse gear meshes with the end of the switching member. A gap is formed in the hydraulic clutch to allow supply of hydraulic pressure to the hydraulic clutch.

[Operation] With the configuration described above, from the time after the shift operation by the shift mechanism of the continuously variable transmission until the end of the switching member meshes with the meshing portion of either the forward gear or the reverse gear. A gap is formed in the groove communicating with the hydraulic clutch, the supply of hydraulic pressure to the hydraulic clutch is allowed by the hydraulic supply stop mechanism, and the shift operation is performed more smoothly and reliably, thereby improving safety during the shift operation. .

Embodiment An embodiment of the present invention will be described below in detail with reference to the drawings.

1 to 14 show an embodiment of the present invention. In FIG. 6, reference numeral 2 denotes a continuously variable transmission. The continuously variable transmission 2 continuously and steplessly changes the gear ratio by a belt 12 described later, and drives a driving force of an internal combustion engine (not shown) at a required gear ratio according to a running state of a vehicle (not shown). It is automatically converted and taken out.

The continuously variable transmission 2 includes a driving pulley 6 on an input shaft 4 communicating with an internal combustion engine (not shown), a driving pulley 10 on an output shaft 8, and a connection between the driving pulley 6 and the driven pulley 10. A belt 12 is wound around.

The drive-side pulley 6 has a drive-side fixed pulley portion 14 fixed to the input shaft 4 and a drive-side movable pulley portion 16 mounted on the input shaft 4 so as to be axially movable and non-rotatable. ing. The driven pulley 10 includes a driven fixed pulley piece 18 fixed to the output shaft 8, and a driven movable pulley piece 20 that is axially movable and non-rotatably mounted on the output shaft 8. have.

The drive side movable pulley piece 16 has a drive side hydraulic chamber 22. The driven-side movable pulley piece 20 has a driven-side hydraulic chamber 24. The hydraulic pressure receiving area of the driving side movable pulley portion piece 16 of the driving side hydraulic chamber 22 is set to be larger than the hydraulic pressure receiving area of the driven side movable pulley portion piece 20 of the driven side hydraulic chamber 24. As a result, the belt ratio as the gear ratio is changed by controlling the hydraulic pressure acting on the drive-side hydraulic chamber 22.

Further, in the specific drive side hydraulic chamber 24, the driven side movable pulley part 20 is moved in a direction of decreasing the groove width between the driven side fixed pulley part 18 and the driven side movable pulley part 20. An urging means 26 comprising an urging spring or the like is provided. This urging means 26
When the hydraulic pressure is low, such as at the time of starting, a large speed ratio on the full low side is maintained, and the holding force of the belt 12 is maintained to prevent slippage.

The input shaft 4 is provided with an oil pump 28. Oil pump 28 pumps oil stored in oil pan 30. The oil pump 28 is provided in communication with the drive side and driven side hydraulic chambers 22 and 24 through first and second oil passages 32 and 34, respectively. A primary pressure control valve 36 for controlling a primary pressure, which is an input shaft sheave pressure, is provided in the middle of the first oil passage 32. A constant pressure control valve 38 is provided in the first oil passage 32 closer to the oil pump 28 than the primary pressure control valve 36 to take out the line pressure by controlling the line pressure to a constant control oil pressure.
Are provided in communication. The primary pressure control valve 36 is provided with a first three-way solenoid valve 42 for primary pressure control in communication with a third oil passage 40.

A line pressure control valve 44 having a relief valve function for controlling a line pressure as a pump pressure is provided in the middle of a second oil passage 34 communicating the oil pump 28 and the driven side hydraulic chamber 24.
Are provided in communication. The line pressure control valve 44 is provided with a second three-way solenoid valve 48 for line pressure control in communication with a fourth oil passage 46.

Further, in the middle of the second oil passage 34 on the driven side hydraulic chamber 24 side of the portion where the line pressure control valve 44 communicates, a clutch pressure control valve for controlling a hydraulic pressure acting on a hydraulic clutch 60 described later. 50 are connected. The clutch pressure control valve 50 is provided with a third three-way solenoid valve 54 for clutch pressure control in communication with a fifth oil passage 52.

Further, the control oil pressure of a constant pressure taken out from the constant pressure control valve 38 is supplied to the primary pressure control valve 36 and the first three-way solenoid valve 42 for primary pressure control, the line pressure control valve 44 and the second three-way solenoid valve 48 for line pressure control, These valves 38, 36, 42, 44, 48, 50, 54 are connected to the clutch pressure control valve 50 and the clutch pressure control third three-way solenoid valve 54, respectively.
The oil channels 56 communicate with each other.

The clutch pressure control valve 50 is provided in communication with a clutch hydraulic chamber 62 of a hydraulic clutch 60 through a seventh oil passage 58. A pressure sensor 64 is provided in communication with the seventh oil passage 58.

The hydraulic clutch 60 includes an input-side casing 66 attached to the output shaft 8, the clutch hydraulic chamber 62 provided in the casing 66, and a piston 68 pushed by hydraulic pressure acting on the clutch hydraulic chamber 62. And this piston 68
An annular spring 70 for urging the piston in the retreating direction, a first pressure plate 72 provided to be able to advance and retreat by the pushing force of the piston 68 and the urging force of the annular spring 70, and a friction plate 74 on the output side. A second pressure plate 76 fixed to the casing 66.

The hydraulic clutch 60 is provided in communication with the output shaft 8 and a final output shaft 78 rotatably fitted to the output shaft 8.
When the hydraulic pressure acting on the clutch hydraulic chamber 62 is increased, the hydraulic clutch 60 pushes the piston 68 so that the first pressure plate 72 and the second pressure plate 76 are brought into close contact with the friction plate 74 and engaged. It operates, and it becomes a so-called clutch connection state. On the other hand, when the clutch pressure acting on the clutch hydraulic chamber 62 is reduced, the piston 68 retreats due to the urging force of the annular spring 70, and the first pressure plate 72 and the second pressure plate 76 are separated from each other by the friction plate.
It is separated from 74 to perform a disengagement operation, and a so-called clutch disengagement state is obtained. Due to the engagement / disengagement operation of the hydraulic clutch 60, the driving force output from the output shaft 8 of the continuously variable transmission 2 to the final output shaft 78 is continued.

The final output shaft 78 is connected to a drive wheel (not shown) via an intermediate shaft 80 as shown in FIG. Between the final output shaft 78 and the intermediate shaft 80, a forward / backward switching mechanism 82 for switching the forward / backward engagement state is provided. The forward / reverse switching mechanism 82 includes a forward gear 84 engaged with the intermediate shaft 80 by a bearing 84b, a reverse gear 86 engaged with the intermediate shaft 80 by a bearing 86b, and a switching sleeve 88 as a switching member. ing. The forward gear 84 is a forward output gear fixed to the final output shaft 78.
90, and a forward switching gear 92 rotatably supported by the intermediate shaft 80 so as to mesh with the forward output gear 90.

The reversing gear 86 includes a reversing output gear 94 fixed to the final output shaft 78, a reversing switching gear 96 rotatably supported on the intermediate shaft 80, a reversing output gear 94 and a reversing switching gear. gear
96 and an idler gear (not shown) meshed and connected.

The switching sleeve 88 is mounted on the intermediate shaft 80 so as to be movable in the axial direction and non-rotatable, and one of the forward switching gear 92 and the reverse switching gear 96 is moved by the axial movement.
, And switches between forward and backward engagement.

A drive-side rotation speed sensor 98 for detecting the rotation speed of the drive-side pulley 6 is provided, and a driven-side rotation speed sensor 100 for detecting the rotation speed of the driven-side pulley 10 is provided. A final output rotational speed sensor 102 to be detected is provided.
The pressure sensors 64 and their rotational speed sensors 98, 100, 1
The control unit 104 is a control unit that inputs and controls various signals such as a carburetor throttle opening, a carburetor idle position, an accelerator pedal signal, a brake signal, a power mode option signal, and a shift lever position in addition to the signal 02.
Is provided.

The control unit 104 controls the primary pressure control first control to control the belt ratio and the clutch continuation state of the continuously variable transmission 2 in various control modes according to various input signals.
The opening and closing operations of the three-way solenoid valve 42, the second three-way solenoid valve 48 for line pressure, and the third three-way solenoid valve 54 for clutch pressure control are controlled.

A shift servo valve 106 for supplying and discharging hydraulic pressure is provided to switch the forward / reverse switching mechanism 82. As shown in FIGS. 10 to 13, the shift servo valve 106 is provided with a piston 112 slidably in a cylinder 110 of a valve body 108, and is provided by connecting one end of a shift servo rod 114 to the piston 112. At the other end of the servo rod 114, a shift fork 116 engaged with the switching sleeve 88 of the forward / reverse switching mechanism 82 is fixed.

Shift servo valve 106 has a piston in cylinder 110
When the hydraulic pressure is supplied to the first chamber 118 partitioned by the second chamber 120 and the hydraulic pressure of the second chamber 120 is discharged, the piston 112
Moves the shift servo rod 114 in the direction of arrow A in FIG.
Is moved to the forward switching gear 92 side, the forward switching gear 92 is rotatably connected to the intermediate shaft 80, and is switched to the forward engagement state. On the other hand, when the hydraulic pressure is supplied to the second chamber 120 defined by the piston 112 in the cylinder 110 and the hydraulic pressure in the first chamber 118 is discharged, the shift servo valve 106 In FIG. 3, the shift sleeve 88 is moved in the direction of arrow B to move the switching sleeve 88 to the reversing switching gear 96 by the shift fork 116, and the reversing switching gear 96 is non-rotatably connected to the intermediate shaft 80, and is in the retreat engagement state. Switch to.

In order to supply / discharge hydraulic pressure to / from the hydraulic chamber 62 of the hydraulic clutch 60 and supply / discharge hydraulic pressure to / from the shift servo valve 106,
A manual shift valve 126 is provided which is switched by an operation rod 124 of a shift mechanism 122 of the continuously variable transmission 2.

As shown in FIGS. 10 to 13, the manual shift valve 126 has a spool valve body 132 in a sliding hole 130 of a valve body 128.
Is slidably mounted. The valve body 128 is provided with annular first to seventh groove portions 134 to 146 on the inner peripheral surface of the sliding hole 130. The spool valve 132 has one end connected to the operating rod 124 of the shift mechanism 122 and a first large diameter portion 148 to a fifth large diameter portion slidably in contact with the inner peripheral surface of the slide hole 130.
156, and the first to fifth large diameter portions 148 to 15
The first small diameter portion 158 to the fourth small diameter portion 164 are provided between the six.

The first groove portion 134 provided in the valve body 128 of the manual shift valve 126 communicates with the first passage 166.
The first passage 166 is provided in the first passage 166 of the shift servo valve 106.
It is in communication with room 118. The manual shift valve 1
The second groove 136 provided in the valve body 128 of the 26
A line pressure, which is a hydraulic pressure discharged from the oil pump 28, is supplied to the oil passage 34 and communicates therewith. The third groove 138 provided in the valve body 128 of the manual shift valve 126 communicates with the second passage 168. The second passage 168 communicates with the second chamber 120 of the shift servo valve 106. The fourth groove 140 provided in the valve body 128 of the manual shift valve 126 is connected to the oil pan 30.

Also, the valve body 128 of the manual shift valve 126
Is connected to the third passage 170. The sixth groove 144 of the manual shift valve 126 is
A hydraulic clutch pressure acting on the hydraulic clutch 60 is supplied to the seventh oil passage 58 and communicates with the seventh oil passage 58. The seventh groove 146 of the manual shift valve 126 communicates with the fourth passage 172. The hydraulic pressure in the hydraulic chamber 62 of the hydraulic clutch 60 is supplied and discharged through the third passage 170 and the fourth passage 172 through a fifth passage 174.

In order to prevent the engagement of the hydraulic clutch 60 when the shift servo valve 106 is not operated, a hydraulic supply stop mechanism 176 for stopping supply of a hydraulic pressure to the hydraulic chamber 62 of the hydraulic clutch 60 is provided.

The hydraulic supply stop mechanism 176 is connected to the shift servo valve 106
Are provided integrally. That is, the hydraulic supply stop mechanism 176 has the spool valve element 182 slidably mounted in the slide hole 180 of the valve body 178 provided integrally with the valve body 108 of the shift servo valve 106. The spool valve element 182 is formed integrally with the shift servo rod 114. On the inner peripheral surface of the sliding hole 180 of the valve body 178, annular first groove portions 184 to sixth groove portions 194 are provided.
The spool valve element 182 has a first large diameter portion 196 to a fourth large diameter portion 200 slidably contacting the inner peripheral surface of the sliding hole 180, and a first large diameter portion 196 to a fourth large diameter portion 196. 1 small diameter section 202, 2nd
A small diameter portion 204 is provided.

The first groove 184 provided in the valve body 178 of the hydraulic supply stop mechanism 176 is connected to the oil pan 30. The second groove 186 of the hydraulic pressure supply stop mechanism 176 is connected to the fifth passage 174 by a sixth passage 206. The third groove 188 of the hydraulic pressure supply stop mechanism 176 communicates with the fourth passage 172. The fourth groove 190 of the hydraulic supply stop mechanism 16
Is communicated with the third passage 170. The fifth groove 192 of the hydraulic pressure supply stop mechanism 176 is connected to the fifth passage 174 via a seventh passage 208. Hydraulic supply stop mechanism 1
The sixth groove 194 of 76 is connected to the oil pan 30.

The hydraulic control circuit of the continuously variable transmission 2 is disclosed in FIG. 7 having, for example, two line pressure control valves 44-1 and 44-2.

As shown in FIG. 6, a clutch pressure control valve is provided between the clutch pressure control valve 50 and the pressure sensor 64 in the seventh oil passage 58.
The manual shift valve 126 and the shift servo valve 106 are sequentially arranged from the 50 side, and the manual shift valve 1
26 and the second oil passage 34 are provided in communication with each other through an eighth oil passage 210.

A hydraulic supply stop mechanism 176 for stopping the supply of hydraulic pressure to the hydraulic clutch 60 is formed on the outer periphery of the bearings 84b and 86b of one of the forward gear 84 and the reverse gear 86 after the shift operation by the shift mechanism 122. A gap S is formed in a groove communicating with the hydraulic clutch 60 until the end of the switching sleeve 88, which is a switching member, meshes with the meshing portions 84a, 86a to allow supply of hydraulic pressure to the hydraulic clutch 60. I do.

More specifically, as shown in FIG. 5, after a shift operation in the forward direction by the shift mechanism 122, the gear is formed on one of the forward gear 84 and the reverse gear 86, for example, on the outer periphery of a bearing portion 84b of the forward gear 84. Until the end of the meshing portion 88a of the switching sleeve 88 meshes with the meshing portion 84a, for example, the meshing portion 84a of the forward gear 84 and the meshing portion 88a of the switching sleeve 88 included in the above range are positioned on the same line L. In this case, as shown in FIG. 1, a fourth groove communicating the third passage 170 and the fifth passage 174 is formed.
A gap S is formed in 190, and constitutes the hydraulic supply stop mechanism 176 so as to allow supply of hydraulic pressure to the hydraulic clutch 60.

Also, from after the shift operation in the retreating direction by the shift mechanism 122 until the end of the meshing portion 88a of the switching sleeve 88 meshes with the meshing portion 86a on the outer periphery of the bearing 86b of the reversing gear 86.
For example, when the meshing portion 86a of the reversing gear 86 and the meshing portion 88a of the switching sleeve 88 are located on the same line L, a third passage 172 and a fifth passage 174 communicate with each other as shown in FIG. Groove
A gap S is formed in 188, and the hydraulic supply stop mechanism 176 is configured to allow supply of hydraulic pressure to the hydraulic clutch 60.

 Next, the operation will be described.

The driving force of the internal combustion engine mounted on the vehicle is controlled by the continuously variable transmission 2
Is converted into the desired torque and rotation speed by
The drive wheels (not shown) are driven.

In such a continuously variable transmission 2, when the continuously variable transmission 2 is shifted to the parking range P by the shift mechanism 122, as shown in FIG.
The first small diameter portion 158 of the spool valve body 132
6 to the oil pan 30 side, and the second small diameter portion 160
The passage 168 communicates with the second oil passage 34, the seventh oil passage 58 is closed by the fourth large diameter portion 154 and the fifth large diameter portion 156, and the third passage 170 is moved by the third small diameter portion 162 to the oil pan 30 side. The fourth passage 172 communicates with the oil pan 30 through the outer end of the fifth large-diameter portion 156.

As a result, the shift servo valve 106 discharges the line pressure in the first chamber 118 and supplies the line pressure to the second chamber 120, and the piston 112 moves the shift servo rod 114 in the direction of arrow B to shift the fork 116 As a result, the switching sleeve 88 is moved to the reversing switching gear 96 side, the reversing switching gear 96 is non-rotatably connected to the intermediate shaft 80, and is switched to the retreat engagement state.

At this time, the hydraulic supply stop mechanism 176
The fourth passage 172 and the sixth passage 206 are communicated with each other by the first small diameter portion 202, but the manual shift valve 126 closes the seventh oil passage 58, and connects the third passage 170 and the fourth passage 172 to the oil pan. It communicates with the 30 side.

For this reason, since the clutch pressure is not supplied to the hydraulic chamber 62 of the hydraulic clutch 60, the hydraulic clutch 60 is not engaged, the driving force output from the continuously variable transmission 2 is cut off, and the vehicle cannot move backward.

When the continuously variable transmission 2 is shifted to the reverse range R by the shift mechanism 122, the manual shift valve 126 is moved to the first small diameter portion 158 of the spool valve body 132 as shown in FIG.
Thereby, the first passage 166 communicates with the oil pan 30 side, the second small diameter portion 160 communicates the second passage 168 with the second oil passage 34, and the third small diameter portion 162 connects the third passage 170 with the oil pan 30 side. The fourth passage 172 communicates with the seventh oil passage 58 through the fourth small-diameter portion 164 through the communication.

As a result, the shift servo valve 106 discharges the line pressure in the first chamber 118 and supplies the line pressure to the second chamber 120, and the piston 112 moves the shift servo rod 114 in the direction of arrow B to shift the fork 116 As a result, the switching sleeve 88 is moved to the reversing switching gear 96 side, the reversing switching gear 96 is non-rotatably connected to the intermediate shaft 80, and is switched to the retreat engagement state.

At this time, the hydraulic supply stop mechanism 176
The fourth passage 172 and the sixth passage 206 communicate with each other through the first small diameter portion 202.

For this reason, the clutch pressure as the hydraulic pressure in the seventh oil passage 58 is supplied to the hydraulic chamber 62 of the hydraulic clutch 60 via the fourth passage 172, the sixth passage 206, and the fifth passage 174, and the hydraulic clutch 60 is engaged. The driving force output from the continuously variable transmission 2 is connected, and the vehicle is in a state where the vehicle can retreat.

When the continuously variable transmission 2 is shifted to the drive range D by the shift mechanism 122, the manual shift valve 126 is moved to the first small diameter portion 158 of the spool valve body 132 as shown in FIG.
Communicates the first passage 166 with the second oil passage 34,
The second passage 168 communicates with the oil pan 30 side by the small diameter portion 160, and the third passage 170 is connected to the seventh oil passage by the third small diameter portion 162.
The fourth passage 172 communicates with the oil pan 30 through the fourth small diameter portion 164.

As a result, the shift servo valve 106 supplies the line pressure to the first chamber 118 and discharges the line pressure in the second chamber 120, and the piston 112 moves the shift servo rod 114 in the direction of the arrow A, so that the shift fork 116 To move the switching sleeve 88 to the forward switching gear 92 side, rotatably connect the forward switching gear 29 to the intermediate shaft 80, and switch to the forward engaged state.

At this time, the hydraulic supply stop mechanism 176
The third passage 170 and the seventh passage 208 communicate with each other through the second small diameter portion 204.

For this reason, the clutch pressure as the hydraulic pressure in the seventh oil passage 58 is supplied to the hydraulic chamber 62 of the hydraulic clutch 60 via the third passage 170, the seventh passage 207, and the fifth passage 174, and the hydraulic clutch 60 is engaged. The driving force output from the continuously variable transmission 2 is connected, and the vehicle is ready to move forward.

When the continuously variable transmission 2 is shifted to the low range L by the shift mechanism 122, as shown in FIG. 13, the manual shift valve 126 causes the first passage 166 to be connected to the second oil passage by the first small diameter portion 158 of the spool valve body 132. 34, the second passage 168 is communicated to the oil pan 30 side by the second small diameter portion 160, the third passage 170 is communicated to the seventh oil passage 58 by the third small diameter portion 162, and the fourth small diameter portion 164 is Fourth passage 172 through oil pan 30
Communicate with the side.

As a result, the shift servo valve 106 releases the line pressure to the first chamber 118 and the line pressure to the second chamber 120, and causes the piston 112 to move the shift servo rod 114 in the direction of arrow A so that the shift fork 116 To move the switching sleeve 88 to the forward switching gear 92 side, rotatably connect the forward switching gear 92 to the intermediate shaft 80, and switch to the forward engaged state.

At this time, the hydraulic supply stop mechanism 176
The third passage 170 and the seventh passage 208 communicate with each other through the second small diameter portion 204.

For this reason, the clutch pressure as the hydraulic pressure of the seventh oil passage 58 is supplied to the hydraulic chamber 62 of the hydraulic clutch 60 via the third passage 170, the seventh passage 208, and the fifth passage 174, and the hydraulic clutch 60 is engaged. The driving force output from the continuously variable transmission 2 is connected, and the vehicle is ready to move forward.

When the continuously variable transmission 2 is shifted to the drive range D by the above-described shift mechanism 122, as shown in FIG.
For example, if the respective ends of the meshing portion 84a of the forward gear 84 and the meshing portion 88a of the switching sleeve 88 are located on the same line L, as shown in FIG. A gap S is formed in the fourth groove portion 190 that communicates with the hydraulic fluid, and the supply of the hydraulic pressure to the hydraulic clutch 60 is allowed by the hydraulic pressure supply stop mechanism 176.

When shifting the continuously variable transmission 2 to the reverse range R, when the respective ends of the meshing portion 86a of the reverse gear 86 and the meshing portion 88a of the switching sleeve 88 are located on the same line L, As shown in FIG. 3, a gap S is formed in the third groove portion 188 communicating the fourth passage 172 and the fifth passage 174, and the supply of the hydraulic pressure to the hydraulic clutch 60 is permitted by the hydraulic supply stop mechanism 176. .

Thus, when the continuously variable transmission 2 is shifted to the drive range D or the reverse range R,
By permitting the supply of oil pressure to the hydraulic clutch 60 when the respective ends of the meshing portion 84a of 84 or the meshing portion 86a of the reversing gear 86 and the meshing portion 88a of the switching sleeve 88 are located on the same line L. As shown by the solid line in FIG. 14, the clutch pressure at the time of shifting can be filled a little earlier, and the shifting operation can be performed smoothly and reliably, which is practically advantageous.

In addition, the shift servo valve 106 and the manual shift valve 126 are provided in the hydraulic control circuit of the continuously variable transmission 2 so as to be used together with the clutch pressure operating program. The safety at the time of operation can be improved.

Further, the forward gear 84 and the reverse gear of the forward / reverse switching mechanism 82
Since there is no need to specially process the switching sleeve 86 and the switching sleeve 88, the structure can be kept simple, the manufacturing is easy, the cost can be reduced, and it is economically advantageous.

[Effects of the Invention] As described above in detail, according to the present invention, forward / reverse switching in which the forward / backward engagement state of the continuously variable transmission having the hydraulic clutch is switched by the forward gear, the reverse gear, and the switching member between the two gears. A shift servo valve that supplies and discharges hydraulic pressure to switch the forward / reverse switching mechanism is provided, and a manual switching operation is performed by the shift mechanism to supply and discharge hydraulic pressure to the hydraulic clutch and supply hydraulic pressure to the shift servo valve. A shift valve is provided, and a hydraulic supply stop mechanism for stopping the supply of hydraulic pressure to the hydraulic clutch is formed on the outer periphery of the bearing portion of either the forward gear or the reverse gear after the shift operation by the shift mechanism of the continuously variable transmission. A gap is formed in the groove communicating with the hydraulic clutch until the end of the switching member meshes with the engaged meshing portion to allow the supply of hydraulic pressure to the hydraulic clutch. When the continuously variable transmission is shifted, the gap communicating with the hydraulic clutch immediately before the end of the switching member meshes with the meshing portion formed on the outer periphery of the bearing portion of the forward gear or the reverse gear when shifting the continuously variable transmission. Thus, the supply of the hydraulic pressure to the hydraulic clutch can be permitted, and the clutch pressure at the time of shifting can be filled up as soon as possible, so that the shift operation can be performed smoothly and reliably. Further, by providing a shift servo valve and a manual shift valve in the hydraulic control circuit of the continuously variable transmission and using the program together with the clutch pressure operating program,
It is possible to prevent jumping out at the time of a shift error and improve safety at the time of a shift operation. Further, since there is no need to specially process the forward gear, the reverse gear, and the switching sleeve of the forward / reverse switching mechanism in terms of manufacturing, the configuration can be kept simple, the manufacturing is easy, and the cost is reduced. It is economically advantageous.

[Brief description of the drawings]

1 to 14 show an embodiment of the present invention, and FIG. 1 is an explanatory view of the operation of the shift servo valve when the forward gear and the switching member are located on the same line when the shift position shifts from R to D. FIG. 2 is a view for explaining the operation of the shift servo valve at the time of FWD (forward), and FIG. 3 is a shift servo when the reverse gear and the switching member when the shift position shifts from D to R are located on the same line. FIG. 4 is an explanatory view of the operation of the valve, FIG. 4 is an explanatory view of the operation of the shift servo valve at the time of REV (reverse), FIG. 5 is an enlarged view of a main part showing the same line, and FIG. FIG. 7 is a schematic diagram of a hydraulic control circuit of the transmission,
FIG. 8 is a plan view of the shift servo valve, FIG. 9 is a front view of the shift servo valve, FIG. 10 is a schematic view showing the operation of the shift servo valve in the P range, and FIG. Schematic diagram showing the operation of the shift servo valve, twelfth
Fig. 13 is a schematic diagram showing the operation of the shift servo valve in the case of the D range, Fig. 13 is a schematic diagram showing the operation of the shift servo valve in the case of the L range, and Fig. 14 is the clutch pressure and clutch solenoid duty in each range. FIG. In the figure, 2 is a continuously variable transmission, 4 is an input shaft, 6 is a driving pulley, 8 is an output shaft, 10 is a driven pulley, 12 is a belt, 22 is a driving hydraulic chamber, and 24 is a driven hydraulic pressure. Chamber, 28 is an oil pump, 32 is a first oil passage, 34 is a second oil passage,
36 is a primary pressure control valve, 38 is a constant pressure control valve, 40 is a third oil passage, 42 is a first three-way solenoid valve for primary pressure control,
44 is a line pressure control valve, 46 is a fourth oil passage, 48 is a second three-way solenoid valve for line pressure control, 50 is a clutch pressure control valve, 52
Is a fifth oil passage, 54 is a third three-way solenoid valve for controlling clutch pressure, 56 is a sixth oil passage, 58 is a seventh oil passage, 60 is a hydraulic clutch, 62 is a clutch hydraulic chamber, 78 is a final output shaft,
80 is an intermediate shaft, 82 is a forward / reverse switching mechanism, 84 is a forward gear, 84a
Is a meshing portion, 86 is a reverse gear, 86a is a meshing portion, 88 is a switching sleeve, 88a is a meshing portion, 90 is a forward output gear, 92 is a forward switching gear, 94 is a reverse output gear, and 96 is a reverse switching. gear,
104 is a control unit, 106 is a shift servo valve, 116 is a shift fork, 118 is a first chamber, 120 is a second chamber, 122 is a shift mechanism, 126 is a manual shift valve, 176 is a hydraulic supply stop mechanism, and 210 is an eighth It is an oil passage.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F16H 59/00-61/12 F16H 61/16-61/24 F16H 63/40-63/48 F16D 25 / 00-39/00 B60K 41/00-41/28

Claims (1)

(57) [Claims] 1. A hydraulic clutch which is engaged / disengaged by supplying / discharging hydraulic pressure so as to continuously convert and take out a driving force of an internal combustion engine according to a required gear ratio in accordance with a traveling state of a vehicle and to output a driving force. A continuously variable transmission having a forward / backward switching mechanism for switching the forward / backward engaged state of the continuously variable transmission by a forward gear, a reverse gear, and a switching member between the two gears, and performing a switching operation of the forward / backward switching mechanism. A shift servo valve for supplying and discharging hydraulic pressure is provided to supply and discharge hydraulic pressure to and from the hydraulic clutch, and a manual shift valve that is switched by a shift mechanism of the continuously variable transmission to supply hydraulic pressure to the shift servo valve is provided. A hydraulic supply stop mechanism for stopping supply of hydraulic pressure to a hydraulic clutch is provided after the shift operation by the shift mechanism of the continuously variable transmission from the forward gear or the rearward gear. A gap is formed in a groove portion communicating with the hydraulic clutch until the meshing portion formed on the outer periphery of the bearing portion of one of the gears and the end of the switching member mesh with each other, and the hydraulic pressure to the hydraulic clutch is changed. A shift control device for a continuously variable transmission, wherein the shift control device is configured to allow supply.