JPH0620866B2 - Parking mechanism for vehicles with automatic transmission - Google Patents

Description

TECHNICAL FIELD The present invention relates to a parking mechanism for a vehicle equipped with an automatic transmission.

[Prior Art] A parking mechanism is a parking arm with a claw that is displaced by a mechanical interlocking device such as a link mechanism by an operating device such as a speed control lever provided in a driver's seat, and an output shaft of an automatic transmission. And a return gear that urges the parking arm toward the parking release side.

In addition, in order to secure the minimum ground clearance of the automatic transmission, the parking mechanism is placed on the top or side of the transmission, and the manual valve of the valve body is placed on the top or side of the transmission case. There is.

[Problems to be Solved by the Invention] However, in the parking mechanism as described above, when the speed select lever is erroneously operated to the parking range while the vehicle is traveling, the parking arm is displaced in the parking gear direction to cause the pawl of the parking arm to move. The collision with the teeth of the parking gear causes abnormal noise and vibration, and also tends to cause unnecessary friction and the like. Further, when the speed selector lever is operated to the parking range by mistake while the vehicle is traveling, the parking arm is displaced in the parking gear direction and the claws of the parking arm collide with the teeth of the parking gear to release the parking arm. If the durability of the return spring biased to the side is impaired and it stops functioning, vibrations during running may occur even when the speed selection lever is set to a position other than the parking range, or the parking arm may be placed above the parking gear or When it is placed on the side, the parking arm is displaced in the parking gear direction by its own weight, the claws of the parking arm collide with the teeth of the parking gear, and abnormal noise and vibration are generated, and unnecessary friction is generated. The durability of the parking arm and the parking gear may be reduced.

The present invention, in the case where a driver mistakenly operates the operating means to the parking range or the return spring for urging the parking arm toward the parking release side does not function while the vehicle is traveling, the parking arm moves in the parking gear direction. To prevent the collision of the claws of the parking arm and the teeth of the parking gear and the generation of abnormal noise and vibration due to the collision, and to provide a parking mechanism for a vehicle with an automatic transmission having excellent durability. The purpose is to

[Means for Solving the Problem] A parking mechanism for a vehicle with an automatic transmission according to the present invention that achieves the above object is rotatably supported by a parking gear 2 connected to a drive shaft of the vehicle and a fixed member. A parking arm 3 provided with a pawl 3B that is displaced radially outside of the parking gear 2 by its own weight and meshes with the parking gear 2 and that has a pawl 3B that meshes with the parking gear 2; The operating means provided in the driver's seat has a return spring 31 for urging the pawl 3B toward the parking release side which is separated from the parking gear 2.
21 and the parking arm are mechanically connected to each other via elastic means 29, and when the driver operates the operating means 21 in the parking range, the parking arm 3 is displaced against the spring 31 to move the pawl. In a parking mechanism 20 of a vehicle with an automatic transmission having an interlocking means 30 for engaging 3B with the parking gear 2, a hydraulic cylinder 41 to which pressure oil is supplied from an oil pressure control device of the automatic transmission according to vehicle operating conditions. A piston 43 slidably fitted in the hydraulic cylinder 41 and urging the parking arm 3 toward the parking release side by the hydraulic pressure supplied to the hydraulic cylinder 41; and a piston 43 arranged on the piston 43. A parking arm lock mechanism 4 including a spring 44 that urges the piston 43 against hydraulic pressure is provided.

[Operation and Effect of the Invention] In the parking mechanism for a vehicle with an automatic transmission according to the present invention, when the vehicle is stopped and the vehicle driver operates the operating means to the parking range, the interlocking means causes the parking arm to move the pawl of the parking arm. The parking mechanism is disengaged to engage the teeth of the parking gear, and the parking mechanism is brought into the engaged state.

On the other hand, when the driving condition of the vehicle matches the preset driving condition of the vehicle such as the high-speed running condition, the parking arm lock mechanism responds to the driving condition of the vehicle from the hydraulic control device of the automatic transmission. Pressure oil is supplied to the hydraulic cylinder, the piston in the hydraulic cylinder slides by the pressure oil, and the piston urges the parking arm to be maintained on the parking release side. At this time, when the vehicle driver operates the operating means to the parking range, the interlocking means attempts to displace the parking arm to the engagement side where the pawl of the parking arm meshes with the teeth of the parking gear. Since the arm is fixed to the parking release side by the parking arm lock mechanism, even if the operating means is switched to the parking range, only the elastic means is displaced, the parking arm is kept on the release side and the engagement of the parking mechanism is avoided. To be

If the durability of the return spring that urges the parking arm to the release side is impaired and it stops functioning, when the operating condition of the vehicle matches the preset operating condition of the vehicle, the parking arm is similarly operated. Is maintained on the parking release side by the parking arm lock mechanism.

Therefore, it is possible to prevent the generation of abnormal noise and vibration due to the collision of the claws of the parking arm and the teeth of the parking gear, and the durability of the parking arm and the parking gear is improved.

[Embodiment] Next, the present invention will be described based on an embodiment shown in the drawings.

Reference numeral 1 denotes an automatic transmission mounted on a front engine front drive (FF) engine which is installed in a front portion of an automobile and drives front wheels. The transmission case 10 is a fluid connected to an output shaft of the engine. The first shaft 12 includes a transmission device 11, a first shaft 12 coaxial with an output shaft of the fluid transmission device 11, and a second shaft 13 arranged obliquely above the first shaft 12 in parallel. Further, one or both of the second shaft 13 and the second shaft 13 are provided with a transmission such as a planetary gear type, a constant mesh type, a continuously variable transmission, etc., in which a speed change is performed by a fluid pressure actuator, and a transmission mechanism such as a gear or a chain. It is connected. A parking gear 2 is provided on the second shaft 13 in a state that it is always connected to the front wheel drive shaft. Reference numeral 14 is a differential device connected to the second shaft, 15 is a front wheel drive shaft, 16 is a valve body of a hydraulic control device mounted on the upper portion of the transmission case 10 in this embodiment, and 17 is a valve body for covering the valve body. The oil pan fastened to the upper surface of the transmission case is shown.

The parking mechanism 20 of the present invention is provided in the driver's seat, and sets the selected speed positions of parking (stop) P, reverse (reverse) R, neutral (neutral) N, drive (forward) D, second S, and low L. Speed selector lever 21 which is an operating means
And one end 3A supported by the transmission case 10 so as to be rotatable in the same plane as the parking gear 2 and having a claw 3B projecting downward in the middle part thereof, and the parking provided above the parking gear. Arm 3 and the parking arm 3
A return spring 31 interposed between the parking arm 3 and the transmission case 10 so as to bias the pawl 3B in a direction (upward in the drawing) away from the parking gear 2, and a parking arm that locks the parking arm 3. It comprises a lock mechanism 4 and a link mechanism 30 which is an interlocking means for transmitting the operation of the speed selecting lever 21 to the parking arm 3. The link mechanism 30 has one end 22A in the direction perpendicular to the second shaft 13.
Of the manual shaft 22 rotatably attached to the transmission case 10 in a state of protruding outward, the link lever 23 fixed to one end 22A of the manual shaft, the lower end 21B of the speed-selecting lever and the link lever. A push-pull cable 24 connecting between the distal end 23B, a detent cam 25 attached to the manual shaft 22, and an end 26A pivotally attached to the detent cam 25, and having a slightly larger diameter conical shape. The end 26B has a conical surface 28A that slides with a taper portion 27A that is inserted into a guide cylinder 27 provided on the parking arm 3 of the transmission case and that has a spring retainer 26C in the middle, and one end of which is the spring. A coil spring 29, which is an elastic means locked to the retainer 26C, is installed on the back, and is fitted onto the conical tip of the parking rod 26 by the spring 29. Conical parking cam 28.

The parking arm lock mechanism 4 which is the gist of the present invention,
A hydraulic cylinder 41 provided below the tip 3C of the parking arm 3 of the transmission case 10, and the hydraulic cylinder 41
A piston 43 slidably fitted in the arm 42 and protruding upward is composed of a piston 43 in contact with the lower side of the front end portion 3C of the parking arm, and a spring 44 installed on the piston 43. . The lock mechanism 4 is configured such that when pressure oil is supplied from an oil passage 45 provided in the transmission case 10 so as to connect the hydraulic cylinder 41 and a hydraulic control device in the valve body 16, the piston 43 operates as follows. The spring 44 is compressed to fix the parking arm 3 to the upper side (parking release side) in the figure, and the parking arm 3 is locked so that the pawl 3B does not enter between the teeth of the parking gear 2. When the hydraulic cylinder 41 is exhausted, the piston 43 is set downward in the figure by the action of the spring 44, and the parking arm 3 is unlocked. While the parking arm 3 is locked by the lock mechanism 4, the driver selects the speed selecting lever 21 as shown in FIG.
Is set to the P range, the parking rod 26 moves to the parking position, but the parking arm 3 locks the locking mechanism 4.
Since it is locked by, the spring 29 only displaces, and the parking cam 28 does not move.

As shown in FIG. 5, the hydraulic oil supplied from the hydraulic cylinder 41 is adjusted by adjusting the projecting hydraulic pressure of the oil pump P with a hydraulic pressure adjusting device A such as a regulator valve in accordance with vehicle traveling conditions such as an engine throttle opening. The line pressure generated in L1 is converted to the hydraulic pressure (governor pressure) related to the vehicle speed by the governor valve G, and the oil passage 45
The governor pressure increasing according to the vehicle speed is supplied to the hydraulic cylinder 41 via. Reference numeral M denotes a manual valve that is interlocked with a speed selecting lever 21 provided in the valve body 16. Accordingly, it is possible to set the lock mechanism of the parking arm to be unlocked only under the condition of the set speed or less such as 5 km / h or less per hour.

FIG. 6 shows a second embodiment.

In the present embodiment, the parking arm 3 is extended in the direction of the one end 3A on the pivot side of the transmission case 10, and the parking arm lock mechanism 4 similar to that of the first embodiment is provided in the transmission case above the extension 3D. Is provided. In this embodiment, the piston 43 has a small-diameter land 47 for receiving the oil pressure of the upper-end oil chamber 46 and a large-diameter land 49 for receiving the oil pressure of the oil chamber 46 between the lands, as shown in FIG. Is directly supplied with the line pressure of the oil passage L1, and to the oil chamber 48 via the manual valve M.
Connected to oil passage L2 that connects to L1 or drain port m. In this way, by connecting the oil passage 48 to the oil passage L2 in the hydraulic control device that is discharged only when the speed selection lever 21 is set to the P range, the parking gear 2 is operated outside the P range. It can be set so as to prevent the parking arm 3 from engaging with the claw 3B.

Further, when the engine throttle opening is large due to the line pressure in the oil chamber 46 (when the line pressure is high), the engagement between the parking gear 2 and the claw 3B of the parking arm 3 can be prevented.

Although the hydraulic cylinder is used as the parking arm lock mechanism in the above embodiments, it is natural that other driving means such as electromagnetic force and air pressure may be used.

[Brief description of drawings]

FIG. 1 is a side view of an automatic transmission for a front engine front drive showing one embodiment of a parking mechanism for a vehicle with an automatic transmission according to the present invention, and FIG. 2 is a configuration of a parking mechanism for a vehicle with an automatic transmission according to the present invention. 3 is a perspective view showing the operation of the parking gear and the parking arm, FIG. 5 is a schematic view of the essential parts of the hydraulic control circuit, and FIG. 6 is a schematic view of a vehicle with an automatic transmission according to the present invention. FIG. 7 is a schematic view of the essential parts of the second embodiment of the parking mechanism, and FIG. 7 is a schematic view of the essential parts of the hydraulic control circuit. In the figure 2 ... Parking gear, 3 ... Parking arm, 4 ... Parking arm lock mechanism 31 ... Return spring, 21 ... Speed selection lever (operation means), 29 ... Spring (elastic means) 30 ... Link Mechanism (interlocking means), 41 ... hydraulic cylinder,
43 …… Piston, 44 …… Spring

Claims (3)

[Claims] 1. A parking gear connected to a drive shaft of a vehicle, and a parking gear rotatably supported by a fixed member. The parking gear is located at an upper position where it is displaced by its own weight radially outside of the parking gear and meshes with the parking gear. A parking arm provided with a pawl that meshes with the parking gear, and a return spring that biases the parking arm toward a parking release side where the pawl separates from the parking gear, and an operating means provided in a driver's seat. And the parking arm are mechanically connected to each other via elastic means, and when the driver operates the operating means to the parking range, the parking arm is displaced against the return spring and the pawl is moved to the parking gear. In a parking mechanism of a vehicle with an automatic transmission that has an interlocking device that meshes with the A hydraulic cylinder to which pressure oil is supplied from the control device according to the vehicle operating condition, and the parking arm is attached to the parking release side by the hydraulic pressure that is slidably fitted into the hydraulic cylinder and is supplied to the hydraulic cylinder. A parking mechanism for a vehicle with an automatic transmission, comprising a parking arm lock mechanism comprising a urging piston and a spring urging the piston against the hydraulic pressure. 2. A parking mechanism for a vehicle with an automatic transmission according to claim 1, wherein the hydraulic cylinder communicates with an oil passage to which a governor pressure varying according to a vehicle speed is supplied. . 3. The automatic transmission according to claim 1, wherein the hydraulic cylinder communicates with an oil passage in which hydraulic pressure is generated when the operating means is set to a traveling range. Vehicle parking mechanism.