Patent Publication Number: US-2005126326-A1

Title: Gear shift apparatus

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to a gear shift apparatus, and more particularly, to a combined By-wire and Tiptronic type gear shift apparatus which is constructed to allow a shift lever to be operated along a drive lane and a Tiptronic lane defined in a shift lever guide.  
      2. Description of the Related Art  
      Conventionally, in a vehicle, as a gear shift apparatus for connecting a transmission and a shift lever with each other, a mechanical link mechanism has been commonly used. Recently, in order to save the manufacturing cost, reduce occupying space, decrease the size and improve the operability of a shift lever, and to raise the degree of freedom in locating component elements inside a vehicle, a By-wire type gear shift apparatus has been disclosed in the art, in which a transmission and a shift lever are connected to each other using an electric circuit. As another method for improving the operability of the shift lever, a Tiptronic type gear shift apparatus has been also disclosed in the art, in which a gear shift in a transmission is performed by manipulating a switch provided on, for example, a steering wheel (see Japanese Unexamined Patent Application Publication No. 2003-287112).  
       FIGS. 6 and 7  illustrate a conventional By-wire and Tiptronic type gear shift apparatus which is obtained by combining a By-wire type and a Tiptronic type gear shift apparatuses.  FIG. 6  is a perspective view illustrating a principle part inside a vehicle, and  FIG. 7  is an enlarged perspective view illustrating a shift lever guide section inside a vehicle.  
      In  FIG. 6 , the reference numeral  101  indicates a steering wheel,  102  indicates a driver&#39;s seat,  103  indicates a front passenger&#39;s seat,  104  indicates a console box provided between the driver&#39;s seat  102  and the front passenger&#39;s seat  103 ,  105  indicates a shift lever guide installed on the console box  104 ,  106  indicates a shift lever operated in the shift lever guide  105 ,  107  indicates a shift-up switch provided to a left side the steering wheel  101  on a rear side thereof,  108  indicates a shift-down switch provided to a right side of the steering wheel  101  on the rear side thereof, and  109  indicates a Tiptronic mode selection switch provided to a lower side of the steering wheel  101  on the rear side thereof.  
      As it can be readily seen from  FIG. 7 , the shift lever guide  105  is defined with a drive lane  105   a  in which desired shift positions P, R, D, D 1  and D 2  are appropriately arranged, a Tiptronic lane  105   b  which has a shift-up position T 1  and a shift-down position T 2 , and a conversion lane  105   c  which connects the drive lane  105   a  and the Tiptronic lane  105   b  with each other. The shift lever  106  can be operated only along these three lanes. The reference numeral P indicates a parking position, R indicates a reverse position, D indicates a drive position, D 1  indicates a third position, and D 2  indicates a second position.  
      In the gear shift apparatus constructed as mentioned above, by introducing the shift lever  106  into the drive lane  105   a  and placing the shift lever  106  at any desired shift position, it is possible to shift the transmission to the desired shift position. Also, by introducing the shift lever  106  into the Tiptronic lane  105   b  after passing through the conversion lane  105   c  and placing the shift lever  106  at the T 1  position or the T 2  position, it is possible to shift up or shift down the transmission. In a state in which the shift lever  106  is introduced into the Tiptronic lane  105   b,  since it is possible to manipulate the shift-up switch  107  and the shift-down switch  108 , shift-up or shift-down of the transmission can be performed with hands placed on the steering wheel  101 . Also, the switching of a drive mode to a Tiptronic mode or vice versa can be carried out by using the Tiptronic mode selection switch  109  which is provided on the steering wheel  101 .  
      In order to improve the operability of the shift lever  106  and thus the practicability of the gear shift apparatus, it is necessary to provide a predetermined operation feeling to the shift lever  106  so that a driver can perceive through blind touch to which position the shift lever  106  is operated.  
      However, the conventional combined By-wire and Tiptronic type gear shift apparatus, constructed as mentioned above, does not have operation feeling providing means for providing a predetermined operation feeling to the shift lever  106  when the shift lever  106  is introduced into the drive lane  105   a  or into the Tiptronic lane  105   b,  there are limitations in improving the practicability of the gear shift apparatus.  
     SUMMERY OF THE INVENTION  
      Accordingly, the present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a combined By-wire and Tiptronic type gear shift apparatus which is constructed to improve the operability of a shift lever, thereby improving practicability of the device.  
      In order to achieve the above object, according to an aspect of the present invention, there is provided a gear shift apparatus comprising a shift lever guide having a first and second lanes which are substantially parallel to each other and communicates with each other by a bridging lane, a shift lever operated along the lanes of the shift lever guide, an actuator for applying an external force to the shift lever, at least one position sensor for detecting a shift position of the shift lever, a power transmitting mechanism for transmitting the external force generated by the actuator to the shift lever, and a controller for controlling operation of the actuator based on a detection signal output from the position sensor.  
      By the feature of the present invention, the gear shift apparatus comprises a position sensor for detecting a shift position of a shift lever, an actuator for applying an external force to the shift lever and a controller for controlling operation of the actuator. The controller controls operation of the actuator based on a detection signal output from the position sensor. Therefore, since it is possible to provide a predetermined operation feeling to the shift lever depending upon a shift position of the shift lever, a driver can perceive through blind touch where a current shift position is or from which shift position to which shift position gear shift operation is performed, whereby the operability of the shift lever can be improved. Also, when the shift lever is in both a drive lane and a Tiptronic lane, it is possible to provide a predetermined operation feeling to the shift lever, whereby the operability of the shift lever can be further improved. As a result, the practicability and reliability of the combined By-wire and Tiptronic type gear shift apparatus can be significantly improved.  
      According to another aspect of the present invention, the power transmitting mechanism comprises a rack and pinion mechanism which has a rack secured to the shift lever and a pinion secured to a driving shaft of the actuator, and gear teeth of the rack and pinion are formed such that the rack and pinion can slide in a direction parallel to the bridging lane.  
      By the feature of the present invention, a power transmitting mechanism for connecting the shift lever and a driving shaft of the actuator comprises a rack pinion mechanism which is composed of a combination of a rack secured to the shift lever and a pinion secured to the driving shaft of the actuator. Gear teeth of the rack and pinion are formed such that the rack and pinion can slide in a direction parallel to a bridging lane. Therefore, when the shift lever is in both the drive lane and the Tiptronic lane, by using only the rack pinion mechanism, it is possible to provide a predetermined operation feeling to the shift lever, whereby the construction of the power transmitting mechanism, that is, of the gear shift apparatus, can be simplified.  
      According to still another aspect of the present invention, the gear shift apparatus further comprises a switching unit for switching the controller to a drive mode or a Tiptronic mode; and a Tiptronic switch which is manipulated when the controller is switched to the Tiptronic mode to perform gear shift in a transmission.  
      By the feature of the present invention, the gear shift apparatus comprises a switching unit and a Tiptronic switch. Therefore, because it is possible to perform the gear shift of a transmission through the manipulation of the switches, the gear shifting operation in the transmission can be performed in a convenient manner, and thereby the safe driving of a vehicle can be ensured.  
      According to yet still another aspect of the present invention, the switching unit and the Tiptronic switch are provided on a steering wheel of a vehicle.  
      By the feature of the present invention, the switching unit and the Tiptronic switch are provided on a steering wheel of a vehicle. Therefore, as it is possible to manipulate the switching unit and the Tiptronic switch with hands placed on the steering wheel, the safe driving of a vehicle can be ensured, and the operability of the gear shift apparatus can be improved.  
      The gear shift apparatus according to the present invention provides advantages as described below. Since the gear shift apparatus comprises a position sensor for detecting a shift position of a shift lever, an actuator for applying an external force to the shift lever and a controller for controlling operation of the actuator, the controller controls operation of the actuator based on a detection signal output from the position sensor, it is possible to provide a predetermined operation feeling to the shift lever depending upon a shift position of the shift lever. Therefore, a driver can perceive through blind touch where a current shift position is or from which shift position to which shift position gear shift operation is performed, whereby the operability of the shift lever can be improved. Also, when the shift lever is in both a drive lane and a Tiptronic lane, it is possible to provide a predetermined operation feeling to the shift lever, whereby the operability of the shift lever can be further improved. As a result, the practicability and reliability of the combined By-wire and Tiptronic type gear shift apparatus can be significantly improved. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a constructional view illustrating a gear shift apparatus in accordance with an embodiment of the present invention;  
       FIG. 2  is a plan view of a shift lever guide;  
       FIG. 3  is a cross-sectional view taken along a line III-III of  FIG. 1 ;  
       FIG. 4  is a cross-sectional view taken along a line IV-IV of  FIG. 1 ;  
       FIGS. 5A and 5B  are tables illustrating exemplary control table stored in a controller of the gear shift apparatus according to the present invention;  
       FIG. 6  is a perspective view illustrating a principle part inside a vehicle; and  
       FIG. 7  is an enlarged perspective view illustrating a shift lever guide section inside a vehicle. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
      Hereinafter, a gear shift apparatus in accordance with an embodiment of the present invention will be described with reference to  FIGS. 1 through 5 .  FIG. 1  is a constructional view illustrating a gear shift apparatus in accordance with an embodiment of the present invention;  FIG. 2  is a plan view of a shift lever guide;  FIG. 3  is a cross-sectional view taken along a line III-III of  FIG. 1 ;  FIG. 4  is a cross-sectional view taken along a line IV-IV of  FIG. 1 ; and  FIGS. 5A and 5B  are tables illustrating exemplary control table stored in a controller of the gear shift apparatus according to the present invention.  
      Referring to  FIG. 1 , a gear shift apparatus in accordance with an embodiment of the present invention mainly comprises a shift lever guide  1 , a fixed shaft  2  which is placed below the shift lever guide  1 , a rotary cylinder  3  which is rotatably fitted around the fixed shaft  2 , a bracket  4  which is secured to the rotary cylinder  3 , a shift lever  6  which is coupled to the bracket  4  by a pin  5  to be pivoted in a rotating direction of the rotary cylinder  3  and in a direction perpendicular to the rotating direction of the rotary cylinder  3 , a shift knob  7  which is mounted to an upper end of the shift lever  6 , a solenoid  8  which pivots the shift knob  7  about the pin  5  in the direction perpendicular to the rotating direction of the rotary cylinder  3 , a casing  9  for transmitting a driving force of the solenoid  8  to the shift lever  6 , a first position sensor  10  for detecting a driving position of the solenoid  8 , a rack  11  which is secured to the shift lever  6 , a pinion  12  which is meshed with the rack  11 , an actuator  13  for rotatably driving the pinion  12 , a second position sensor  14  for detecting an rpm of the actuator  13 , a shift-up switch  15 , a shift-down switch  16 , a Tiptronic mode selection switch  17 , and a controller  18  for controlling operation of the solenoid  8  and the actuator  13 .  
      As can be readily seen from  FIG. 2 , the shift lever guide  1  is defined with a drive lane  1   a  (a first lane), a Tiptronic lane  1   b  (a second lane), and a conversion lane  1   c  (bridging lane) which form an H-shaped configuration. Each of the lanes  1   a,    1   b  and  1   c  is formed to have a width which is slightly greater than a diameter of the shift lever  6 . The shift lever  6  can be operated only in a lengthwise direction of the respective lanes  1   a,    1   b  and  1   c.  Referring to  FIG. 2 , since the characters have the same meanings as in the conventional shift lever guide shown in  FIG. 7 , descriptions thereof will be omitted herein.  
      The shift knob  7  is provided with a proximity sensor  19  and a push switch  20 . When the hand of a driver approaches the shift knob  7 , the proximity sensor  19  senses the hand and converts the entire system into an operating state. The push switch  20  functions to hold the shift lever  6  at an operated position.  
      While a conventional solenoid can be used as the solenoid  8 , in order to save electric power, it is preferable to use a self-supporting type solenoid.  
      The casing  9  allows the shift lever  6  to be operated along the drive lane  1   a  and the Tiptronic lane  1   b.  The casing  9  functions to transmit a driving force of the solenoid  8  to the shift lever  6 . In this preferred embodiment of the present invention, as shown in  FIG. 3 , the casing  9  is formed to have a length which is slightly greater than an operating range of the shift lever  6  operated along the drive lane  1   a.  The casing  9  is located to extend in a direction where the drive lane  1   a  and the Tiptronic lane  1   b  are arranged.  
      While any conventional position sensor may be used as the first position sensor  10 , in order to easily detect a positional change of a driving shaft  8   a  of the solenoid  8  which is slidably operated, it is preferable to use a slide type rheostat or encoder. Also, while, any conventional position sensor may be used as the second position sensor  14 , in order to easily detect a positional change of a driving shaft  13   a  of the actuator  13  which is rotatably operated, it is preferable to use a rotary type variable resistor or encoder.  
      As shown in  FIG. 4 , the rack  11  is formed in the shape of a plate when viewed in its longitudinal cross-section. The rack  11  is formed, on a lower surface thereof, with rack gear teeth  11   a.  Pinion gear teeth  12   a  which are meshed with the rack gear teeth  11   a  are formed on a circumferential outer surface of the pinion gear  12 . The rack and pinion gear teeth  11   a  and  12   a  are formed to extend parallel to the conversion lane (bridging lane)  1   c.  The rack and pinion gear teeth  11   a  and  12   a  are meshed with each other such that the pinion  12  can be freely slid with respect to the rack  11  in a direction parallel to the conversion lane (bridging lane)  1   c.    
      While any conventional actuator which is employed as a driving source can be used as the actuator  13 , in consideration of easy controllability due to a small size, it is preferable to use a rotary motor.  
      The shift-up switch  15 , the shift-down switch  16 , and the Tiptronic mode selection switch  17  can be provided on a rear surface of steering wheel not shown.  
      Referring to  FIG. 1 , the controller  18  comprises an input section  21 , a memory  22 , a first driver circuit  23 , a second driver circuit  24 , an output unit  25 , and a CPU  26 . In the input section  21 , there are inputted a first position signal ‘a’ which is output from the first position sensor  10 , a second position signal ‘b’ which is output from the second position sensor  14 , a first switch signal ‘c’ which is output from the shift-up switch  15 , a second switch signal ‘d’ which is output from the shift-down switch  16 , a third switch signal ‘e’ which is output from the Tiptronic mode selection switch  17 , a fourth switch signal ‘f’ which is output from the proximity switch  19 , and a fifth switch signal ‘g’ which is output from the push switch  20 . In the memory  22 , control signals ‘h’ for the actuator  13 , which are associated with the first and second position signals ‘a’ and ‘b’, and control signals ‘i’ for the solenoid  8 , which are associated with the third and fifth switch signals ‘e’ and ‘g’, are stored in the form of tables. The first driver circuit  23  generates a drive signal ‘j’ for the actuator  13 , from the control signal ‘h’ read from the memory  22 . The second driver circuit  24  generates a drive signal ‘k’ for the solenoid  8 , from the control signal ‘i’ read from the memory  22 . The output unit  25  functions to output the drive signals ‘j’ and ‘k’ and the switch signals ‘c’ and ‘d’. The CPU  26  functions to control entire these component parts.  
      Referring to  FIG. 1 , the memory  22  includes a data and program storage part  22   a,  and first and second control signal storage parts  22   b  and  22   c.  Data and programs for analyzing the signals ‘a’ through ‘g’ inputted into the input section  21  and a program for operating the CPU  26  are stored in the data and program storage part  22   a.  As shown in  FIG. 5A , the control signals ‘h 1 ’ through ‘h 8 ’ for the actuator  13 , which are associated with the first switch signals ‘a 1 ’ and ‘a 2 ’ and the second switch signals ‘b 1 ’ through ‘b 8 ’, are stored in the first control signal storage part  22   b.  Also, as shown in  FIG. 5B , the control signal ‘i 1 ’ through ‘i 4 ’ for the solenoid  8 , which are associated with the third switch signals ‘e 1 ’ and ‘e 2 ’ and the fifth switch signals ‘g 1 ’ and ‘g 2 ’, are stored in the second control signal storage part  22   c.    
      The first position signal ‘a 1 ’ is a signal which is output from the first position sensor  10  when the shift lever  6  is positioned in the drive lane  1   a  of the shift lever guide  1 , and the first position signal ‘a 2 ’ is a signal which is output from the first position sensor  10  when the shift lever  6  is positioned in the Tiptronic lane  1   b  of the shift lever guide  1 . The second position signals ‘b 1 ’ through ‘b 8 ’ are signals output from the second position sensor  14  when the shift lever  6  is positioned in the respective shift positions P, R, D, D 1  and D 2  in the drive lane  1   a  and the shift lever  6  is positioned in the respective shift positions T 1  and T 2  in the Tiptronic lane  1   b.  The third switch signal ‘e 1 ’ is a signal which is output from the Tiptronic mode selection switch  17  when the Tiptronic mode selection switch  17  is turned on, and the third switch signal ‘e 2 ’ is a signal which is output from the Tiptronic mode selection switch  17  when the Tiptronic mode selection switch  17  is turned off. Also, the fifth switch signal ‘g 1 ’ is a signal which is output from the push switch  20  when the push switch  20  is turned on, and the fifth switch signal ‘g 2 ’ is a signal which is output from the push switch  20  when the push switch  20  is turned off.  
      The CPU  26  is operated based on the operating program stored in the data and program storage part  22   a  of the memory  22 . The CPU  26  analyzes the respective signals ‘a’ through ‘g’ which are inputted into the input section  21 , based on the data and programs which are stored in the data and program storage part  22   a,  and then, in conformity with the analyzed signals, outputs the drive signals ‘j’ and ‘k’ or the switch signals ‘c’ and ‘d’.  
      Each of the first and second driver circuits  23  and  24  comprises a D/A converter for D/A converting the control signal ‘h’ or ‘i’ output from the CPU  26  and a signal amplifier for amplifying the D/A converted signal. The first and second driver circuits  23  and  24  function to output the drive signals ‘j’ and ‘k’ through the output unit  25  to the actuator  13  and the solenoid  8 .  
      Hereinafter, operation of the gear shift apparatus according to the present invention, constructed as mentioned above, will be described.  
      First, as a driver grasps the shift knob  7 , the proximity switch  19  which is provided on the shift knob  7  senses this situation and converts the entire system into an operating state.  
      In a state in which the shift lever  6  is positioned in the drive lane  1   a  of the shift lever guide  1  when the driver grasps the shift knob  7  or the driver manipulates the shift knob  7  to introduce the shift lever  6  into the drive lane  1   a  of the shift lever guide  1 , if the driver operates the shift lever  6  from one shift position of the shift positions P, R, D, D 1  and D 2  assigned to the drive lane  1   a  to another shift position, the shift lever  6  is rotated about an axis of the fixed shaft  2 , and a rotating force of the shift lever  6  is transmitted to the second position sensor  14  through the rack  11  and the pinion  12 , whereby a second position signal ‘b 1 ’ to ‘b 6 ’ which is associated with the corresponding shift position is output from the second position sensor  14 . Also, the first position signal ‘a 1 ’, which indicates that the shift lever  6  is in the drive lane  1   a,  is output from the first position sensor  10 . The CPU  26  reads out a control signal ‘h 1 ’ to ‘h 6 ’ for the actuator  13 , which is associated with the signals ‘a 1 ’ and ‘b 1 ’ to ‘b 6 ’, from the first control signal storage part  22   b  of the memory  22 . The control signal ‘h 1 ’ to ‘h 6 ’ is converted into the drive signal ‘j’ for the actuator  13 , by the first driver circuit  23 , and then output through the output unit  25 . By this fact, the actuator  13  is driven, and a driving force of the actuator  13  is transmitted to the shift lever  6  through the pinion  12  and the rack  11 , whereby a predetermined operation feeling is provided on the shift knob  7 .  
      An operation feeling provided to the shift lever  6  is changed depending upon a shift position. For example, when gear shift is effected between the D position and the D 1  position and between the D 1  position and the D 2  position, predetermined click feelings which are different from each other are provided to the shift lever  6 , and, when gear shift is effected between the P position and the R position and between the R position and the D position, in order to ensure safe driving of the vehicle, resistant feelings for indicating that gear shift is prohibited are provided to the shift lever  6 . The gear shift between the P position and the R position and between the R position and the D position is enabled only when the push switch  20  provided on the shift knob  7  is pressed, and thereby, predetermined operation feelings which are different from each other can be provided to the shift lever  6 .  
      The first position signal ‘a 1 ’ output from the first position sensor  10  and the second position signal ‘b 1 ’ to ‘b 6 ’ output from the second position sensor  14  are transmitted to a transmission controller not shown. By the transmission controller, a shift position of the transmission is shifted to a position which corresponds to the shift position of the shift lever  6  after being shifted.  
      Meanwhile, if the driver moves the shift lever  6  from the drive lane  1   a  to the Tiptronic lane  1   b  of the shift lever guide  1 , the shift lever  6  is rotated about the pin  5 , and a rotating force of the shift lever  6  is transmitted to the driving shaft  8   a  of the solenoid  8  through the casing  9 , whereby the first position signal ‘a 2 ’ indicating that the shift lever  6  is introduced into the Tiptronic lane  1   b  is output from the first position sensor  10 . In this state, if the driver presses the push switch  20  provided on the shift knob  7 , the control signal ‘i 3 ’ for the solenoid  8 , which is associated with the fifth switch signal ‘g 1 ’, is read out from the second control signal storage part  22   c  of the memory  22 , and the drive signal ‘k’ for the solenoid  8  is output through the output unit  25 . By this fact, the driving shaft  8   a  of the solenoid  8  is extended out of the solenoid  8 , and the shift lever  6  can be stably maintained in the Tiptronic lane  1   b.  After the shift lever  6  is introduced into the Tiptronic lane  1   b,  if the driver operates the shift lever  6  to the position T 1  or T 2 , the shift lever  6  is rotated about the axis of the fixed shaft  2 , and a rotating force of the shift lever  6  is transmitted to the second position sensor  14  through the rack  11  and the pinion  12 , whereby the second position signal ‘b 7 ’ or ‘b 8 ’, which corresponds to the shift position T 1  or T 2 , is output from the second position sensor  14 . The CPU  26  reads out a control signal ‘h 7 ’ or ‘h 8 ’ for the actuator  13 , which is associated with the signals ‘a 2 ’ and ‘b 7 ’ or ‘b 8 ’, from the first control signal storage part  22   b  of the memory  22 . The control signal ‘h 7 ’ or ‘h 8 ’ is converted into the drive signal ‘j’ for the actuator  13 , by the first driver circuit  23 , and then output through the output unit  25 . By this fact, the actuator  13  is driven, and a driving force of the actuator  13  is transmitted to the shift lever  6  through the pinion  12  and the rack  11 , whereby a predetermined operation feeling is provided to the shift knob  7 . After the shift lever  6  is operated to the shift position T 1  or T 2 , if the driver removes the hand from the shift knob  7 , this situation is sensed by the proximity switch  19  provided on the shift knob  7 , and the actuator  13  is driven, whereby the shift lever  6  is returned to a center position in the Tiptronic lane  1   b.    
      As the shift lever  6  is operated to the shift position T 1  or T 2 , the first position signal ‘a 2 ’ output from the first position sensor  10  and the second position signal ‘b 7 ’ or ‘b 8 ’ output from the second position sensor  14  are transmitted to the transmission controller not shown. By the transmission controller, the transmission is shifted up or down.  
      If the shift lever  6  is introduced into the Tiptronic lane  1   b  of the shift lever guide  1  by the driver and the push switch  20  provided on the shift knob  7  is pressed, or the Tiptronic mode selection switch  17  provided on the steering wheel is pressed by the driver, it is possible to shift up and down the transmission using the shift-up switch  15  and the shift-down switch  16 . Also, introduction of the shift lever  6  from the drive lane  1   a  into the Tiptronic lane  1   b  is enabled only when the shift lever  6  is in the shift position D of the drive lane  1   a.  When the shift lever  6  is in the shift position D of the drive lane  1   a,  if the Tiptronic mode selection switch  17  is manipulated, the control signal ‘i 1 ’ for the solenoid  8 , which is associated with the third switch signal ‘e 1 ’, is read out from the second control signal storage part  22   c  of the memory  22 , and the drive signal k for the solenoid  8  is output through the output unit  25 . By this fact, the driving shaft  8   a  of the solenoid  8  is protruded, and the shift lever  6  is stably maintained in the Tiptronic lane  1   b.    
      After manipulating the Tiptronic mode selection switch  17 , if the driver manipulates the shift-up switch  15  or the shift-sown switch  16 , the first switch signal ‘c’ output from the shift-up switch  15  or the second switch signal ‘d’ output form the shift-down switch  16  is transmitted to the transmission controller not shown. By the transmission controller, the transmission is shifted up or down.  
      Conversion from a Tiptronic mode into a drive mode can be effected by turning off the Tiptronic mode selection switch  17  in a state in which the shift lever  6  is in the center position in the Tiptronic lane  1   b.  By turning off the Tiptronic mode selection switch  17 , the control signal ‘i 2 ’ for the solenoid  8 , which is associated with the third switch signal ‘e 2 ’, is read out from the second control signal storage part  22   c  of the memory  22 , and the drive signal ‘k’ for the solenoid  8 , which corresponds to the control signal ‘i 2 ’, is output through the output unit  25 . By this fact, the driving shaft  8   a  of the solenoid  8  is retracted, and the shift lever  6  is introduced from the Tiptronic lane  1   b  into the drive lane  1   a  by the casing  9 .  
      As apparent from the above description, the gear shift apparatus according to the present invention comprises first and second position sensors  10  and  14  for detecting shift positions of a shift lever  6 , an actuator  13  for applying an external force to the shift lever  6 , and a controller  18  for controlling operation of the actuator  13 . The controller  18  controls operation of the actuator  13  based on position signals ‘a’ and ‘b’ output from the first and second position sensors  10  and  14 . Therefore, since it is possible to provide a predetermined operation feeling to the shift lever  6  depending upon a shift position of the shift lever  6 , a driver can perceive through blind touch what a current shift position is or from what shift position to what shift position gear shift operation is performed, whereby operability of the shift lever  6  can be improved. Also, since the gear shift apparatus includes a rack  11  and a pinion  12  which transmits an external force generated by the actuator  13  to the shift lever  6  irrespective of a shift position of the shift lever  6 , when the shift lever  6  is not only in a drive lane  1   a  but also in a Tiptronic lane  1   b,  it is possible to provide a predetermined operation feeling to the shift lever  6 , whereby operability of the shift lever  6  can be further improved. As a result, practicability and reliability of the combined By-wire and Tiptronic type gear shift apparatus can be significantly improved.  
      Also, in the gear shift apparatus according to the present invention, a power transmitting mechanism for connecting the shift lever  6  and a driving shaft  13   a  of the actuator  13  comprises a rack pinion mechanism which is composed of a combination of the rack  11  secured to the shift lever  6  and the pinion  12  secured to the driving shaft  13   a  of the actuator  13 . Therefore, when the shift lever  6  is not only in the drive lane  1   a  but also in the Tiptronic lane  1   b,  only by using a pair of the rack pinion mechanism, it is possible to provide a predetermined operation feeling to the shift lever  6 , whereby a construction of the power transmitting mechanism, that is, of the gear shift apparatus, can be simplified.  
      Further, in the gear shift apparatus according to the present invention, a shift-up switch  15 , a shift-down switch  16 , and a Tiptronic mode selection switch  17  are provided. Therefore, because it is possible to perform gear shift of a transmission through manipulation of the switches, gear shifting operation in the transmission can be performed in a convenient manner, and thereby safe driving of a vehicle can be ensured.  
      Moreover, in the gear shift apparatus according to the present invention, the shift-up switch  15 , the shift-down switch  16  and the Tiptronic mode selection switch  17  are provided on a steering wheel of a vehicle. Therefore, it is possible to manipulate the switches  15 ,  16  and  17  with the hands placed on the steering wheel, safe driving of a vehicle can be ensured, and operability of the gear shift apparatus can be improved.  
      While it was described in the above embodiment that the solenoid  8  and the casing  9  are employed as means for moving the shift lever  6  into the drive lane  1   a  or the Tiptronic lane  1   b,  a person having ordinary skill in the art will readily recognize that at least one spring capable of stably supporting the shift lever  6  in the drive lane  1   a  and the Tiptronic lane  1   b  may be used instead of the above configuration, on the basis of a supporting point pass principle.