Control system for electronic actuated shifter

A shifter mechanism for a motor vehicle includes a shifter lever, a park switch indicating when the shifter lever is out of a park position, and an electric actuator movable between a locking position and an unlocking position to lock and unlock the lever. An interlock switch indicates when the vehicle operator desires to move the lever. A controller moves the actuator when an ignition switch indicates an ignition is on, a brake switch indicates a brake pedal is pressed, and the interlock switch is actuated. The controller also moves the actuator when the lever is not in the park position and the interlock switch is actuated. The controller actuates a vehicle key lock actuator when the ignition switch indicates the vehicle ignition is on or when the park switch indicates that the lever is not in the park position.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not Applicable

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

Not Applicable

REFERENCE TO MICROFICHE APPENDIX

Not Applicable

FIELD OF THE INVENTION

The present invention generally relates to a shifter mechanism for controlling transmissions of motor vehicles and, more particularly, to a control system for a shifter mechanism having an electronic actuated solenoid assembly for holding a shifter lever in a desired gear position against inadvertent movement to other gear positions.

BACKGROUND OF THE INVENTION

In a motor vehicle, a shifter lever of a shifter mechanism is typically pivotable over a series of positions representative of desired transmission gears such as, for example, park (P), reverse (R), neutral (N), drive (D), and low gear (M). The shifter mechanism is connected to the motor vehicle automatic transmission by a suitable mechanical and/or electronic operating linkage to effect actuation of the transmission to the selected gear when the shifter lever is pivoted to the transmission gear's representative position. The shifter mechanism is typically provided with a detent assembly which releasably holds the shifter lever mechanism in a desired position to prevent inadvertent movement to other positions but permits desired movement to other positions. The detent assembly typically includes a mechanical actuator which is manually operated to release the detent assembly and permit manual pivoting of the shifter lever mechanism to a new position.

Attempts have been made to replace the mechanical actuator with an electronic actuator. For example, see U.S. Pat. No. 5,220,984, the disclosure of which is expressly incorporated herein in its entirety by reference. This shifter mechanism attempts to simplify construction by providing an electrically actuated detent assembly having a locking pawl moved by an electric solenoid.

While these prior electronic shifter mechanisms eliminate the need for mechanical actuators, they are relatively complex and expensive to implement. Vehicle electronics must be adapted to determine when shifting gears is permissible so that gears are not switched under inappropriate conditions. Additionally, the shifter mechanism requires cables to receive signals from the brake pedal and the key lock in order to determine vehicle conditions. Both of which drive up the cost and complexity of the vehicle. Accordingly, there is a need in the art for an improved electronic shifter mechanism.

SUMMARY OF THE INVENTION

The present invention provides an electronic shifter mechanism which overcomes at least some of the above-noted problems of the related art. According to the present invention, a shifter mechanism for a motor vehicle comprises, in combination, a shifter lever movable along a shift path between a plurality of gear positions including a park position, a park switch providing a signal indicating when the shifter lever is out of the park position, and a lock assembly including an electric actuator movable between a locking position wherein the shifter lever is locked in one of the plurality of gear positions and an unlocking position wherein the shifter lever is movable along the shift path between the plurality of gear positions. A manually-actuated interlock switch provides a signal indicating the vehicle operator desires to move the shifter lever between the plurality of gear positions. A controller is operably connected to the park switch to receive the signal from the park switch, operably connected to the interlock switch to receive the signal from the interlock switch, and operably connected to the electric actuator to selectively actuate the electric actuator. The controller is adapted to receive an input signal from a vehicle ignition switch indicating whether a vehicle ignition is on and an input signal from a vehicle brake switch indicating whether a vehicle brake pedal is pressed. The controller moves the actuator to the unlocking position when the input signal from the vehicle ignition switch indicates the vehicle ignition is on, the input signal from the vehicle brake switch indicates that the vehicle brake pedal is pressed, and the signal from the interlock switch indicates that the vehicle operator has actuated the interlock switch. The controller also moves the actuator to the unlocking position when the signal from the park switch indicates that the shifter lever is not in the park position and the input signal from the interlock switch indicates that the vehicle operator has actuated the interlock switch.

According to another aspect of the present invention, a shifter mechanism for a motor vehicle comprises, in combination, a shifter lever movable along a shift path between a plurality of gear positions including a park position, a park switch providing a signal indicating when the shifter lever is out of the park position, and a lock assembly including an electric actuator movable between a locking position wherein the shifter lever is locked in one of the plurality of gear positions and an unlocking position wherein the shifter lever is movable along the shift path between the plurality of gear positions. A manually-actuated interlock switch provides a signal indicating the vehicle operator desires to move the shifter lever between the plurality of gear positions. A controller is operably connected to the park switch to receive the signal from the park switch, operably connected to the interlock switch to receive the signal from the interlock switch, and operably connected to the electric actuator to selectively actuate the electric actuator. The controller is adapted to receive an input signal from a vehicle ignition switch indicating whether a vehicle ignition is on. The controller actuates a vehicle key lock actuator when the input signal from the vehicle ignition switch indicates the vehicle ignition is on. The controller also actuates the vehicle key lock actuator when the signal from the park switch indicates that the shifter lever is not in the park position.

According to yet another aspect of the present invention, a shifter mechanism for a motor vehicle comprises, in combination, a shifter lever movable along a shift path between a plurality of gear positions including a park position, a park switch providing a signal indicating when the shifter lever is out of the park position, and a lock assembly including an electric actuator movable between a locking position wherein the shifter lever is locked in one of the plurality of gear positions and an unlocking position wherein the shifter lever is movable along the shift path between the plurality of gear positions. A manually-actuated interlock switch provides a signal indicating the vehicle operator desires to move the shifter lever between the plurality of gear positions. A controller is operably connected to the park switch to receive the signal from the park switch, operably connected to the interlock switch to receive the signal from the interlock switch, and operably connected to the electric actuator to selectively actuate the electric actuator. The controller is adapted to receive an input signal from a vehicle ignition switch indicating whether a vehicle ignition is on and an input signal from a vehicle brake switch indicating whether a vehicle brake pedal is pressed. The controller moves the actuator to the unlocking position when the input signal from the vehicle ignition switch indicates the vehicle ignition is on, the input signal from the vehicle brake switch indicates that the vehicle brake pedal is pressed, and the signal from the interlock switch indicates that the vehicle operator has actuated the interlock switch. The controller also moves the actuator to the unlocking position when the signal from the park switch indicates that the shifter lever is not in the park position and the input signal from the interlock switch indicates that the vehicle operator has actuated the interlock switch. The controller actuates a vehicle key lock actuator when the input signal from the vehicle ignition switch indicates the vehicle ignition is on, and the controller actuates the vehicle key lock actuator when the signal from the park switch indicates that the shifter lever is not in the park position. The controller includes all control circuits used to control both the electric actuator and the vehicle key lock actuator.

From the foregoing disclosure and the following more detailed description of various preferred embodiments it will be apparent to those skilled in the art that the present invention provides a significant advance in the technology and art of motor vehicle shifter mechanisms. Particularly significant in this regard is the potential the invention affords for providing a high quality, reliable, low cost assembly. Additional features and advantages of various preferred embodiments will be better understood in view of the detailed description provided below.

It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various preferred features illustrative of the basic principles of the invention. The specific design features of an electronic shifter mechanism as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes of the various components, will be determined in part by the particular intended application and use environment. Certain features of the illustrated embodiments have been enlarged or distorted relative to others to facilitate visualization and clear understanding. In particular, thin features may be thickened, for example, for clarity or illustration. All references to direction and position, unless otherwise indicated, refer to the orientation of the shifter lever mechanism illustrated in the drawings. In general, up or upward generally refers to an upward direction inFIG. 1and down or downward generally refers to a downward direction inFIG. 1. Also in general, fore or forward refers to a direction toward the front of the vehicle, that is, generally toward the left inFIG. 1and aft or rearward refers to a direction toward the rear of the vehicle, that is, generally toward the right inFIG. 1.

DETAILED DESCRIPTION OF CERTAIN PREFERRED EMBODIMENTS

It will be apparent to those skilled in the art, that is, to those who have knowledge or experience in this area of technology, that many uses and design variations are possible for the improved shifter lever mechanism disclosed herein. The following detailed discussion of various alternative and preferred embodiments will illustrate the general principles of the invention with reference to a particular electronic shifter mechanism for an automatic transmission of a motor vehicle such as an automobile, sport utility vehicle (SUV), or truck. Other embodiments suitable for other applications will be apparent to those skilled in the art given the benefit of this disclosure.

Referring now to the drawings,FIGS. 1 to 3show an electronic shifter mechanism10according to a preferred embodiment of the present invention. The illustrated shifter mechanism10includes a frame or base12, a shifter lever assembly14pivotably mounted to the base12, and a lock or detent assembly16releasably holding the shifter lever assembly14in a desired one of a plurality of gear positions18against undesired or inadvertent movement to the other gear positions18. The illustrated shifter mechanism10includes the gear positions18of park (P), reverse (R), neutral (N), drive (D), and low gear (M) but an other suitable plurality of gear positions18can alternatively be utilized.

The base12is adapted to be attached to the motor vehicle in a fixed position such as a floor or console and can be formed of any suitable size and shape. The illustrated base12is generally planar and shaped to engage the motor vehicle in a desired manner. The forward end of the base12is provided with an opening or hole20for receiving a mechanical fastener such as bolts to secure the base12to the motor vehicle. The rearward end of the base12is provided with a pair of openings or holes22for receiving mechanical fasteners such as bolts to secure the base12to the motor vehicle. Other suitable shapes for the base12and the attachment means20,22will be apparent to those skilled in the art. A pair of upwardly extending pivot flanges24are provided near the rear of the base12at lateral sides of the base12. The pivot flanges24are laterally spaced apart and provided with coaxial openings for pivotably mounting the shifter lever assembly14. The flange openings define a horizontal and laterally extending pivot axis26for the shifter lever assembly14. A mounting block or bracket28is provided along the left side of the base12. The mounting bracket28supports an electric actuator or solenoid30of the lock assembly16. The illustrated shifter lock solenoid or actuator30is a linear actuator but any other suitable solenoid actuator can be utilized within the scope of the present invention.

The shifter lock solenoid30is configured to permit a spring to bias a lock pawl into engagement with the shifter lever assembly14to a locking position when the shifter lock solenoid30is unpowered and to selectively move a lock pawl out of engagement with the shifter lever assembly14to a nonlocking position when the shifter lock solenoid30is powered. The lock pawl is sized and shaped to block and limit pivotal movement of the shifter lever assembly14when the lock pawl in its locking position and to permit pivotal movement of the shifter lever assembly14between the gear positions18when the lock pawl is in its unlocking position. The shifter lever assembly14and the shifter lock assembly16can each be of any suitable configuration such as, for example, those disclosed in U S. patent application Ser. No. 10/812,664, the disclosure of which is expressly incorporated herein in its entirety.

The illustrated shifter lever assembly14includes a shifter post or lever32upwardly extending from a shifter yoke34for manually moving the shifter yoke34to change the gear of the transmission. The lower end of the shifter yoke34is sized and shaped to extend between the pivot flanges24of the base12. A horizontal, laterally extending pivot pin cooperates with the flange openings to provide a pivotable connection between the shifter yoke and the base12. Pivotably connected in this manner, the shifter yoke34is pivotable relative to the base12about the laterally extending pivot axis26. The illustrated shifter level mechanism10includes a park switch36indicates when the shifter lever32is in or out of the park position. The illustrated park switch36is open or off when the shifter lever32is in the park position and is closed or on when the shifter lever32is not in the park position.

The illustrated shifter lever32is generally an elongate tube having a central axis and forming a hollow central passage for the passage of wires therethrough. The shifter lever32can be rigidly secured to the shifter yoke34in any suitable manner such as, for example, snap-connectors, welding, adhesives, or mechanical fasteners or the shifter lever can be formed unitary, that is as one piece, with the shifter yoke. With the shifter lever32rigidly secured to shifter yoke34, the shifter yoke34can be selectively pivoted about the pivot axis26by manually applying a forward or rearward force to the shifter lever32. The upper end of the shifter lever32is provided with handle or knob38. The knob38is preferably provided with a shape to provide a suitable gripping surface for the hand of the operator. The illustrated knob38is provided with an operator input or knob interlock switch40which the user presses to selectively shift gear positions.

The illustrated shifter mechanism10includes a controller42that includes all of the shifter control logic that determines when shifting gears is permissible and when shifting gears is not permissible. The controller42is operably connected to the shifter lock solenoid30to power and unpower the shifter lock solenoid30as desired. The controller42is also operably connected to the knob interlock switch40to activate the shifter lock solenoid30under permissible conditions as described in more detail hereinafter. The controller42is further operably connected to the shifter park switch36to determine when the shifter lever32is in the park position.

The controller42is operatively connected to a power source such as the illustrated vehicle positive battery connection44(VB) and the vehicle negative battery connection46(GND). The controller42is also operatively connected to a vehicle brake switch48to receive an input signal which indicates when the vehicle brake pedal50is pressed or applied and when the vehicle brake pedal50is not pressed or unapplied. The illustrated input signal from the vehicle brake switch48is battery voltage when the vehicle brake pedal50is pressed and 0 volts when the vehicle brake pedal50is not pressed. The controller42is further operatively connected to a vehicle ignition switch52to receive an input signal which indicates when the vehicle ignition54is on and when the vehicle ignition54is off. The illustrated input signal from the vehicle ignition switch52is battery voltage when the vehicle ignition54is on and 0 volts when the vehicle ignition54is off.

The illustrated controller54also includes all of the control logic that determines when a vehicle key lock solenoid56should be activated to lock a key within the vehicle ignition key cylinder58so that the key cannot be removed from the vehicle ignition key cylinder58and should be deactivated so that the key can be removed from the vehicle ignition key cylinder58. The controller54is operably connected to the vehicle key lock solenoid56to power and unpower the vehicle key lock solenoid56as desired.

As best shown inFIGS. 3 to 5, the controller42is configured to activate the vehicle key lock solenoid56to lock the key in the vehicle ignition key cylinder58so that the vehicle operator cannot remove the key when the controller42receives an input signal from the vehicle ignition switch52indicating that the vehicle ignition54is on. The controller42is also configured to activate the key lock solenoid56to lock the key in the vehicle ignition key cylinder58so that the vehicle operator cannot remove the key when the controller42receives an input signal from the shifter park switch36indicating that the shifter lever32is not in the park position, that is, that the shifter park switch36is on. Thus, the vehicle key lock solenoid56is activated by the controller42whenever the vehicle ignition switch52is on and/or the shifter park switch36is on. It is noted that when neither of these conditions are present, the controller42deactivates the vehicle key lock solenoid56to unlock the key in the vehicle ignition key cylinder58so that the operator is free to remove the key.

The illustrated controller42is also configured to activate the shifter lock solenoid30and unlock the shifter lever32so that the vehicle operator can switch gear positions when the controller42receives: (1) an input signal from the vehicle ignition switch52indicating that the vehicle ignition54is on, that is, that the vehicle ignition switch52is on; (2) an input signal indication from the vehicle brake switch48indicating that the vehicle brake pedal50is pressed, that is, the vehicle brake switch48is on; and (3) an input signal from the shifter knob interlock switch40indicating that the vehicle operator has depressed the shifter knob interlock switch40, that is, that the shifter knob interlock switch40is on. In the illustrated embodiment, the shifter knob interlock switch40is enabled to trigger the shifter lock solenoid30upon activation when input signals from the vehicle ignition switch52and the vehicle brake switch48are both at battery voltage. When the knob interlock switch40is enabled, the transistor connected to the negative lead of the shifter lock solenoid30is turned on which activates the shifter lock solenoid30to unlock the shifter lever32.

The illustrated controller42is also configured to activate the shifter lock solenoid30and unlock the shifter lever32so that the vehicle operator can switch gear positions when the controller42receives: (1) an input signal from the shifter park switch36indicating that the shifter lever32is not in park, that is, that the shifter park switch36is on; and (2) an input signal from the shifter knob interlock switch40indicating that the vehicle operator has depressed the shifter knob interlock switch40, that is, that the shifter knob interlock switch40is on. In the illustrated embodiment, the shifter knob interlock switch40is enabled to trigger the shifter lock solenoid30upon activation when an input signal from the shifter park switch36is at battery voltage. When the knob interlock switch40is enabled, the transistor connected to the negative lead of the shifter lock solenoid30is turned on which activates the shifter lock solenoid30to unlock the shifter lever32. It is noted that under all other conditions, the controller42prevents the shifter lock solenoid30from activating to prevent the shifter lever32from moving to a different gear position18.

It is apparent from the above detailed description of the present invention, that the illustrated shifter mechanism10combines all shifter control circuits into one controller42which controls both the shifter lock solenoid30and the vehicle key lock solenoid56. Thus, the vehicle electronics or controller60do(es) not have to determine when shifting gears is permissible. With the shifter controller42controlling shifter lock solenoid30conditions, cables between the shifter mechanism10and the vehicle brake pedal50can be cost reduced and/or eliminated. With the shifter controller42controlling the vehicle ignition key lock solenoid56conditions, cables between the shifter mechanism10and the vehicle ignition54can be cost reduced and/or eliminated.

From the foregoing disclosure and detailed description of certain preferred embodiments, it is also apparent that various modifications, additions and other alternative embodiments are possible without departing from the true scope and spirit of the present invention. The embodiments discussed were chosen and described to provide the best illustration of the principles of the present invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the present invention as determined by the appended claims when interpreted in accordance with the benefit to which they are fairly, legally, and equitably entitled.