JPH0463750A - Parking device of automatic transmission - Google Patents

Abstract

PURPOSE:To facilitate the assembly into a transmission by providing a dedicated driving means for driving a locking member on a parking mechanism having the locking member for mechanically locking a driving wheel, beside a driving means for a range switching valve. CONSTITUTION:A parking mechanism 3 is provided with a parking gear 15 of an output shell (for output to a driving wheel) in a transmission case 2, and with a locking member 16 that can be engaged with the parking gear 15. The driving force from a hydraulic driving device 7 can be worked on one end of the locking member 16, and the hydraulic driving device 7 is formed out of a hydraulic cylinder device 21 for which a piston rod 22 is connected with the working point of the locking member 16 through a pin, and of a spring offset electromagnetic type directional control valve 23 for actuating the hydralic cylinder device 21. A solenoid 26 of the directional control valve 23 is actuated and controlled based on the electric signal from a range change-over switch provided on a driver's seat of an automobile.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a parking device for an automatic transmission.

(Prior art) In automatic transmission systems for automobiles, parking range (
P range), reverse range (R range), neutral range (N range), and multiple forward ranges (D range, etc.)
A range switching valve (manual valve) is provided to switch the necessary line pressure circuit between
(See Japanese Patent Application Laid-Open No. 62-275850). This range switching valve is located on the select lever on the driver's seat (actual development 62-1
(see 20028 Publication), it is operated manually.

On the other hand, in an automatic transmission, when the range switching valve is switched to the parking range by the select lever,
A parking mechanism is provided that locks the rotation of the output shaft of the automatic transmission, that is, the drive wheels. This parking mechanism includes a parking gear and a parking ball that prevents rotation of the output shaft by engaging the teeth of the parking gear, and is mechanically linked to a range switching mechanism using a select lever. (See EC-AT Structure and Maintenance, page 7C-51, published by Mazda Motor Corporation, May 1985; N4A-EL Automatic Transmission Structure and Maintenance! Page 7C-70, published by Mazda Motor Corporation, September 1986). That is, when the select lever is operated to the parking range, the parking pole is mechanically interlocked and engaged with the parking gear, thereby locking the rotation of the drive wheels.

(Problems to be Solved by the Invention) The present invention attempts to solve the following technical problems in causing the range switching valve to be operated by a drive means using an electric signal from a driver's seat or the like. It is something.

In a structure in which the range switching mechanism and the parking mechanism are mechanically linked as in the conventional technology, when the range switching valve is driven by the drive means, a large-sized drive means must be used.

In other words, when parking on a slope, a large force is applied to the parking gear from the drive wheels, so a large driving force is required to operate the parking mechanism. Therefore, the driving means becomes large in size.

However, as the drive means becomes larger, it becomes difficult to incorporate it into the mission. Providing such a large drive means outside the transmission not only increases the size of the automatic transmission as a whole, but also complicates the structure because driving force is transmitted to both the range switching mechanism and the parking mechanism. .

(Means for Solving the Problems) The present invention solves these problems in that the range switching mechanism side only requires a small driving force to overcome the sliding resistance of the range switching valve, and the parking mechanism side Focusing on the fact that it can be easily driven by one-way on/off operation, the system eliminates the mechanical link between the range switching mechanism and parking mechanism and uses a system in which each is driven by a separate drive means. By doing this, the driving means on the range switching mechanism side can be made smaller and can be incorporated into the transmission, while the parking mechanism side can use a driving means that can obtain a relatively large driving force. In addition to improving the reliability of operation, we focused on the fact that this parking mechanism can be driven by simple movements, and tried to simplify or downsize the structure of the drive means.We also took advantage of the fact that it can be installed anywhere. This prevents the structure of the automatic transmission as a whole from becoming complicated. Specifically, in an automatic transmission equipped with a driving means that drives and positions a range switching valve, which switches the line pressure circuit between a parking range, a reverse range, a neutral range, and a forward range, to a predetermined range position using an electric signal. , a parking mechanism having a locking member for mechanically locking the driving wheels when the range switching valve is switched to the parking range, the locking member being driven separately from the driving means for the range switching valve. A parking device for an automatic transmission is constructed by providing a dedicated drive means for the automatic transmission.

In this case, the drive means dedicated to the locking member includes a spring that biases the locking member to the unlocked position, and a hydraulic drive device that drives the locking member to the locked position against the biasing force of the spring. be able to.

Further, the hydraulic pressure source of the hydraulic drive device can be constituted by a hydraulic pressure generating device that is driven during engine operation, and an accumulator that accumulates the hydraulic pressure generated by the hydraulic generating device for driving the lock member.

Further, the valve position detection means outputs a parking range detection signal when the range switching valve is positioned in the parking range, and the lock position detection means outputs a lock position detection signal when the lock member of the parking mechanism is driven to the lock position. and an alarm means that outputs an alarm signal when only one of the parking range detection signal and the lock position detection signal is continuously output for a predetermined period of time or more.

(Function) In the parking device for the automatic transmission described above, the driving means for the range switching valve and the driving means for the parking mechanism are separate, so the driving means for the range switching valve does not require a large driving force. Since it is not necessary, its size can be reduced, and therefore it can be easily integrated into the mission.

Further, since the driving means of the parking mechanism only needs to operate the parking mechanism itself or the locking member in one direction in an on/off manner, the structure can be simplified or miniaturized, and the above-mentioned advantages can be achieved. Since the power transmission system can be easily configured even when installed at a location away from the locking member, this drive means can be installed anywhere.

In addition, the drive means dedicated to the lock member is configured by a spring that biases the lock member to the unlock position and a hydraulic drive device that drives the lock member to the lock position against the bias of the spring. Since the hydraulic drive device only needs to be capable of generating a driving force in one direction, the required driving force can be reduced, and the structure can be simplified and downsized.

Furthermore, if the hydraulic power source of the hydraulic drive device is configured by a hydraulic pressure generating device that is driven during engine operation and an accumulator that accumulates the hydraulic pressure generated by this hydraulic generating device for driving the lock member, it is not possible to Even when the vehicle is stopped, the parking mechanism can be operated using the hydraulic pressure stored in the accumulator.

When the valve position detection means outputs the parking range detection signal, the lock position detection means outputs the lock position detection signal, and only one of the parking range detection signal and the lock position detection signal is continuously output for a predetermined period of time or more. With alarm means that outputs an alarm signal, when the parking mechanism is not locked even though the range switching valve is in the parking range, or when the range switching valve is in a range other than the parking range. However, by issuing an alarm when the parking mechanism is locked, it is possible to prevent the vehicle from coasting during parking or adversely affecting the automatic transmission itself. .

(Effects of the Invention) Therefore, according to the parking device for an automatic transmission, the driving means for the range switching valve and the driving means for the parking mechanism are separate, so that the driving means for the range switching valve is By reducing the size, it can be easily integrated into the transmission, and by simplifying or downsizing the structure of the driving means of the parking mechanism,
By utilizing the fact that the automatic transmission can be installed anywhere, the structure of the automatic transmission as a whole can be simplified.

Further, when the driving means of the parking mechanism is configured by a spring and a hydraulic drive device, the necessary driving force of the hydraulic drive device can be reduced, and the structure can be simplified and downsized.

Further, in the case where an accumulator is provided in the hydraulic pressure source of the hydraulic drive device, the parking mechanism can be operated by the hydraulic pressure accumulated in the accumulator even when the engine is stopped.

Further, the valve position detection means outputs the parking range detection signal, the lock position detection means outputs the lock position detection signal, and only one of the parking range detection signal and the lock position detection signal is continuously output for a predetermined period of time or more. In the case where the vehicle is equipped with an alarm means that outputs an alarm signal when the vehicle is parked, even if there is a failure in either the drive means on the range switching mechanism side or the drive means on the parking mechanism side, the vehicle may coast during parking. It is possible to prevent an adverse effect on the automatic transmission body.

(Example) Embodiments of the present invention will be described below based on the drawings.

<Example 1> This example is illustrated in FIGS. 1-5.

In an automatic transmission 1 for an automobile shown in FIG. 1, 2 is a transmission case, and a parking mechanism 3 shown in FIG. 2 is incorporated inside this transmission case. 4 is a valve unit equipped with a range switching valve 5 that switches the line pressure circuit between a parking range, a reverse range, a neutral range, and a plurality of forward ranges; 6 is a valve drive for driving the range switching valve 5; Means, 7 is a hydraulic drive device for driving the parking mechanism 3, 8
11 is a valve unit cover attached to the transmission case 2 via a gasket 9, and 11 is an oil pump attached to the transmission case 2 via a gasket 12.

The valve unit 4 is assembled into the transmission case 2 together with the valve driving means 6. The valve driving means 6 is hydraulic,
It is provided inside the transmission case 2 at a side surface of the valve unit 4 . A shaft 13 for valve position detection, which rotates in conjunction with the range switching valve 5, is attached to the valve driving means 6. This shaft 13 protrudes from the upper surface of the transmission case 2, and is connected to an inhibitor switch 14, which is attached to the upper surface and serves as a valve position detection means.

Further, a hydraulic drive device for the parking mechanism 3 is attached to the upper surface of the transmission case 2. The parking mechanism will be explained below.

Example 1 As shown in FIG. Paul) 16
It is equipped with The locking member 16 has a center portion pivotally supported by a pin 17 on the transmission case 2, and has a locked position in which the engaging portion 16a at one end engages with the teeth of the parking gear 15, and a locked position in which the engagement with the teeth is released. It can be rotated between the unlocked position and the unlocked position, and is urged to the unlocked position by an unlocking spring 18. The other end of the locking member 16 serves as a point of action on which the driving force from the hydraulic drive device 7 acts.

The hydraulic drive unit W7 of the parking mechanism 3 includes a hydraulic cylinder device 21 in which a piston rod 22 is connected with a pin to the point of action of the lock member 16, a spring for operating the hydraulic cylinder device 21, and an offset electromagnetic type. directional control valve 23.

The directional control valve 23 has an input port 23a connected to a hydraulic power source 24, and two output ports 23b connected to a locking port 21a and an unlocking port 21b of the hydraulic cylinder device 21, respectively.

23c. The spool 25 of the directional control valve 23 is provided to move forward and backward using a solenoid 26 and a spring 27, and applies hydraulic pressure to the locking boat 21a and the unlocking boat 21b of the hydraulic cylinder device 21. It is supplied selectively.

Then, the solenoid 26 of the hydraulic drive device 7
It is configured to operate based on an electric signal from a range selector switch (not shown) provided in the driver's seat of the automobile. That is, this range changeover switch outputs an electric signal for range changeover to the valve driving means 6 of the range changeover valve 5. In addition, the parking mechanism 3 receives an ON signal (lock signal) from the solenoid 26 when the vehicle speed is zero and when the parking range signal is output, and receives an ON signal (lock signal) from the solenoid 26 when the wheels are braked and when the range valve 5 is in a range other than parking. It is designed to receive an off signal.

Therefore, when the range switching valve 5 is driven and positioned to the parking range by the valve driving means 6, the solenoid 26 is energized, the hydraulic pressure supply path is switched by the directional control valve 23, and the piston rod 22 of the hydraulic cylinder device 21 moves forward. Then, the lock member 16 is in the lock position,
When the range switching valve 5 is switched to another range, the locking member 16 is driven to the unlock position by demagnetizing the solenoid 26.

- Example 2 This example is shown in FIG. 3, and is an example in which a spring is used to drive the lock member 16 to the lock position, and hydraulic pressure is used to drive the lock member 16 to the unlock position.

That is, in the figure, 31 is a locking spring that urges the locking member 16 to the locked position, and 32 is a hydraulic piston rod that moves forward with hydraulic pressure and drives the locking member 16 to the unlocked position. Further, reference numeral 33 is an electromagnetic stopper means, and the stopper pin 33a is linked to drive positioning of the range selection valve 5 to a range other than the parking range based on an electric signal from the range selection switch.
The locking member 16 is held in the unlocked position by protruding.

In this example, when the range switching valve 5 is driven to a range other than the parking range, the hydraulic piston rod 32 moves forward, the locking member 16 is driven to the unlock position, and the stopper means 33 is activated. Then, the stopper pin 33a will protrude. Further, when the range switching valve 5 is driven and positioned to the parking range, the hydraulic piston rod 32 is moved backward, and the locking member 16
is driven to the lock position by the bias of the locking spring 31.

Therefore, for some reason, the hydraulic piston rod 3
Even if the hydraulic pressure for actuating the lock member 16 decreases, the lock member 16 can be held in the unlocked position by the stopper means 33, and the drive wheels can be prevented from being locked while the vehicle is running. .

Note that a bush lock switch mechanism may be applied to drive the lock member 16. That is, lock member 1
In place of the hydraulic piston rod 32, a self-locking mechanism can be used in which the hydraulic piston rod 32 is locked when pressed once and unlocked when pressed again.

Example 3 - This example is shown in FIG. 4, and in contrast to Example 2, the lock member 16
This is an example in which hydraulic pressure is used to drive to the locked position, and a spring is used to drive to the unlocked position.

That is, in the figure, 35 is a hydraulic piston rod that moves forward by hydraulic pressure and drives the locking member 16 to the locking position. An unlocking spring 18 similar to that in the first embodiment is used to drive the locking member 16 to the unlocked position. Reference numeral 36 denotes an emergency drive means, which has a lever 38 connected to the locking member 16 with a wire 37.

In this example, when the range switching valve 5 is driven to the parking range, the hydraulic piston rod 35
moves forward, and the locking member 16 is driven to the locking position.

On the other hand, when the range switching valve 5 is driven and positioned to a range other than the parking range, the hydraulic piston rod 3
5 moves backward, and the locking member 16 is driven to the unlocked position by the force of the unlocking spring 18.

Therefore, the emergency drive means 36 is used when the lock member 16 is not driven to the unlock position only by the urging force of the lock spring 18 due to abnormal biting of the parking gear 15, or when the lock member 16 is not driven to the unlock position by the urging force of the lock spring 18 alone. It is activated in an emergency such as when the lever is broken, and the rotation of the lever 38 drives the locking member 16 to the unlocked position, making the vehicle ready to travel.

-Regarding the hydraulic power source- Fig. 5 shows the hydraulic power source 24 used in the hydraulic drive device for the parking mechanism on each side.

That is, in the figure, 40 is a pressure oil supply path extending from the oil pump 41, 42 is a return path, and 43 is a relief valve for pressure control. The pressure oil supply path 40 includes, in order from the upstream side, a check valve 44, an accumulator 45 that stores the oil pressure necessary to drive the lock member 16, and an on signal when the oil pressure of more than a predetermined value is accumulated in the accumulator 45. A pressure switch 46 is interposed to output . In this case, the capacity of the accumulator 45 is
should be able to be driven several times.

A timer 49, which operates simultaneously with the closing of the ignition switch 48- to energize the motor 47 for a predetermined time, and an ON signal from the pressure switch 46 are connected to the energizing circuit for the motor 47 that drives the oil pump 40. A switch means 50 is provided to cut off the power supply from the timer 49 to the motor 47.

Therefore, in the case of the hydraulic pressure source 24, when the engine starts operating, the motor 47 is energized via the timer 49 and the switch means 50, the oil pump 41 is operated for a predetermined period of time by the timer 49, and the hydraulic pressure is accumulated in the accumulator 45. Ru. In this case, when a predetermined oil pressure is accumulated in the accumulator 45, the pressure switch 46 is activated, the switch means 50 is turned off, and the operation of the motor 47 is stopped.

Therefore, unnecessary driving of the oil pump 41 or the motor 47 can be eliminated, and even if the engine is stopped, the parking mechanism 3 can be operated by the hydraulic pressure stored in the accumulator 45. .

<Embodiment 2> This example is shown in FIG. 6 and is an example in which an electromagnetic system is adopted as the driving means of the parking mechanism 3. Regarding the reference numerals in the drawings, the same reference numerals are used for elements corresponding to those in the first embodiment. This point also applies to other embodiments.

That is, in the figure, numeral 51 is an electromagnetic drive device that drives the locking member 16 to the locking position by protruding an operating rod 51a. Further, the locking member 16 is urged to the unlocked position by an unlocking spring 18.

<Embodiment 3> This example is shown in FIG. 7 and is an example in which a reversible motor 61 is used as the driving means of the parking mechanism 3.

That is, in the figure, reference numeral 62 denotes a cam member that is supported by the supporter 63 so as to be movable back and forth, contacts the other end of the locking member 16, and rotates the locking member 16 to the locking position against the bias of the unlocking spring 18. be. A pinion 64 is coupled to the output shaft of the motor 61, and a rack 66 is coupled to the cam member 62 via a rod 65.
are interlocking. Further, the cam member 62 is provided so as to be movable with respect to the rod 65 and urged toward the rack 66 by a spring 67.

Therefore, in the case of this embodiment, by moving the rod 65 forward and backward by the motor 61, the cam member 62 is brought into contact with the lock member 16, and the lock member 16 is driven to the lock position. When the cam member 62 and the lock member 16 are disengaged by reverse rotation,
The locking member 16 is returned to the unlocked position by the force of the unlocking spring 18.

<Embodiment 4> This example is shown in FIG. 8, and is an example in which the rack 66 is hydraulically driven.

That is, in the figure, 71 is a hydraulic cylinder device in which a piston rod 72 is connected to the rack 66, and 73 is a hydraulic pressure source. The hydraulic cylinder device 72 has a locking pressure receiving surface 74a that receives hydraulic pressure and drives the rack 36 to the locked position.
and an unlocking pressure receiving surface 74b that drives the rack 36 to the unlock position, and the locking pressure receiving surface 74a is formed to have a larger area than the unlocking pressure receiving surface 74b. On the other hand, the hydraulic power source 73 is also used to drive the power steering, and the motor 7
5, and an accumulator 77 for accumulating hydraulic pressure, and are connected to both ends of the hydraulic cylinder device 71 via valves 78 and 79.

In the case of this example, the hydraulic cylinder device 71 is the locking pressure receiving surface 7
4a is formed to have a larger area than the unlocking pressure receiving surface 74b, so that the locking member 16 can be reliably driven to the locking position.

The driving force for moving the locking member 16 to the unlocked position is supplemented by an unlocking spring 18.

<Regarding alarm means in case of abnormality> Next, a description will be given of what to do when the operations of the parking mechanism 3 and the range switching valve 5 are inconsistent.

That is, in FIG. 9, 81 is a lock position detection means that outputs a lock position detection signal when the lock member 16 of the parking mechanism 3 is driven to the lock position, and 82 is a means for detecting a parking range detection signal from the inhibitor switch 14 and the above lock position. An alarm means 83 is an alarm lamp that outputs an alarm signal when only one of the lock position detection signals from the detection means 81 is continuously output for a predetermined period of time or more.

Therefore, as shown in FIG. 10, after the range switching valve 5 is driven to the parking range and the parking range detection signal is output (ON), even if a predetermined time T has elapsed, the lock position detection means 81 will not lock the range switch valve 5. If the position detection signal is not output (OFF), the warning lamp 83 will light up to notify the driver of the abnormality. Also, on the other hand,
As shown in FIG. 11, even when the parking range detection signal is not output and the lock position detection signal is output, the alarm lamp 83 is turned on. Thereby, it is possible to prevent the driver from coasting the vehicle during parking and from adversely affecting the automatic transmission body.

Note that an alarm buzzer may be used instead of the alarm lamp 83.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention; FIG. 1 is an exploded perspective view of an automatic transmission according to embodiment 1, FIG. 2 is a configuration diagram showing an example of a parking device, and FIGS. FIG. 5 is a circuit diagram showing the hydraulic power source; FIG. 6 is a front view showing the parking device of the second embodiment; and FIG. 7 is the parking device of the third embodiment. A perspective view showing
FIG. 8 is a configuration diagram showing the parking device of Embodiment 4, and FIG.
The figure is a block diagram showing the alarm means, and FIGS. 10 and 11 are time charts showing the mode of alarm generation. 1... Automatic transmission 2... Transmission case 3...
Parking mechanism 4...Valve unit 5...Range switching valve 6...Valve drive means 7...Hydraulic drive device for parking mechanism 14.
...Inhibitor switch (valve position detection means) 15 ... Parking gear 16 ... Lock member 18 ... Unlocking spring 24 ...
... Hydraulic source 31 ... Locking spring 32 ... Hydraulic piston rod for unlocking 3
5...Hydraulic piston rod for lock 40...
...Oil pump (hydraulic generator) 45...
Accumulator 51... Electromagnetic drive device (parking mechanism drive means) 61... Reversible motor (parking mechanism drive means) 81... Lock position detection means 82... Alarm means 83... Alarm lamp fool 1 person] ・Automatic transmission 2-・Tra/Suminon iI case 3 Parking gear 4, Valve unit 5 Lenono switching valve 6-- Valve drive means 7 Parking a Lateral hydraulic drive device 14 - Inhibitor switch (valve position detection means) 15 Parking gear 16 - Locking member 18 - Unlocking spring 24 - Hydraulic source 31 - Locking spring 32 - Hydraulic piston for anorok /Rod 35...
Hydraulic biston rod for lock 40 - Oil pump (hydraulic generator W) 45 Accumulator 51 - ・Electromagnetic drive device! (Parking mechanism driving means) 61...- Reversible motor (parking mechanism driving means) 81-- Lock position detection means 82 Alarm means 83-- IF alarm lamp 1b

Claims (4)

[Claims] (1) In an automatic transmission equipped with a driving means for driving and positioning a range switching valve, which switches the line pressure circuit between a parking range, a reverse range, a neutral range, and a forward range, to a predetermined range position using an electric signal, the above-mentioned A parking mechanism having a locking member for mechanically locking the driving wheels when the range switching valve is switched to the parking range is provided with a parking mechanism that is dedicated to driving the locking member separately from the driving means for the range switching valve. A parking device for an automatic transmission, characterized in that it is provided with a driving means. (2) A claim in which the drive means dedicated to the lock member comprises a spring that biases the lock member to the unlock position, and a hydraulic drive device that drives the lock member to the lock position against the bias of the spring. The parking device for an automatic transmission according to (1). (3) According to claim (2), the hydraulic power source of the hydraulic drive device comprises a hydraulic pressure generating device that is driven during engine operation, and an accumulator that accumulates the hydraulic pressure generated by the hydraulic generating device for driving the lock member. Parking device for the automatic transmission described. (4) Valve position detection means that outputs a parking range detection signal when the range switching valve is positioned in the parking range, and lock position detection that outputs a lock position detection signal when the lock member of the parking mechanism is driven to the lock position. and an alarm means for outputting an alarm signal when only one of the parking range detection signal and the lock position detection signal is continuously output for a predetermined time or more. A parking device for an automatic transmission according to item 1.