Abstract:
A shift control apparatus of a manual transmission is disclosed. To change the gear, the shift control apparatus of a manual transmission according to the embodiment of the present invention includes: a shift lever which is movable in a shift direction and in a select direction; a select lock unit which includes a shaft for limiting the select directional movement of the shift lever; and a controller which controls the select lock unit to limit the select directional movement of the shift lever on the basis of a speed of a vehicle. As a result, a driver can safely shift the gear by preventing unintended shifting to R gear and sense the state of a select lock. Also, the select lock unit is implemented by one solenoid, so that it is possible to reduce the cost thereof, to prevent the overheating of the solenoid, and thus, to extend the life span.

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATION 
     The present application claims the benefit of Republic of Korea Patent Application Serial No. 10-2015-0026445 filed on Feb. 25, 2015, the entirety of which are all incorporated herein by reference. 
     BACKGROUND 
     Field 
     The present disclosure relates to a shift control apparatus of a manual transmission, and more particularly to a shift control apparatus of a manual transmission, which is capable of limiting shifting to R gear when a gear is shifted while driving at a high speed. 
     Description of the Related Art 
     A transmission converts the power generated by an engine into a rotational force suitable for the speed of a vehicle, and transfers. The transmission is installed between a clutch and a propeller shaft. Since the driving condition of the vehicle varies widely, for example, stop, start, low-speed drive, high-speed drive, reverse drive, etc., the transmission must be able to maximize the performance of the engine in response to each of the driving conditions. 
     The transmission is divided into the most basic manual transmission, an automatic transmission, a continuously variable transmission (CVT), a double-clutch transmission (DCT), etc. Regarding the manual transmission, a driver should control the gear shift stage of the transmission himself/herself, and thus, he/she may feel inconvenient. However, the manual transmission has a simple structure and high efficiency. 
     In general, the gear shift of the vehicle is comprised of a forward gear shift from the first gear to fifth or more gear and a reverse gear shift of R (reverse) gear. In the first gear and the second gear which are low gears, a moderating ratio is set to be high in order to create a strong power. In the third gear and fourth gear which are medium gears, a shift ratio is set similar to the engine RPM so as to maintain the driving speed. Also, in the fifth or more gear which is high gear, the shift ratio is set lower than the engine RPM so as to drive at a high speed. 
     However, when a driver of a vehicle equipped with a conventional manual transmission moves a shift lever in the select direction excessively, reverse gear shift is performed many times instead of a high speed shift of the fifth or sixth gear, etc. In this case, an excessive force is added to the transmission, and thus, this is a cause of breakdown, for example, overload generation, etc. 
     SUMMARY 
     One embodiment relates to a shift control apparatus of a manual transmission that includes a shift lever which is movable in a shift direction and in a select direction; a select lock unit which includes a shaft for limiting the select directional movement of the shift lever; and a controller which controls the select lock unit to limit the select directional movement of the shift lever on the basis of a speed of a vehicle. 
     When the speed of the vehicle is in a predetermined speed range, the controller may control the select lock unit to limit the select directional movement of the shift lever. 
     Also, the predetermined speed range may correspond to a third gear or a fourth gear. 
     The select lock unit may include a solenoid which includes a permanent magnet fixed to the shaft, and a coil surrounding a circumference of the shaft in a cylindrical shape. The controller may control a current flowing through the coil and change a polarity of a magnetic field formed in the solenoid, so that the permanent magnet fixed to the shaft is moved. 
     The select lock unit may insert the shaft into a locking groove formed in a select lever, and thus, may limit the select directional movement of the shift lever. 
     Also, the shift control apparatus of a manual transmission may further include a magnetic field sensor which senses whether the select directional movement of the shift lever is limited or not. 
     The shaft  310  may include a position sensing magnet  350  provided on an end thereof. The magnetic field sensor  400  may sense a position of the shaft  310  on the basis of a magnetic field change depending on a distance change of the position sensing magnet  350 . 
     Also, the magnetic field sensor may be composed of a hall integrated circuit (IC). 
     The controller may receive information on the speed of the vehicle from an electronic control unit (ECU). 
     Another embodiment is a shift control apparatus of a manual transmission that includes: a shift lever which is movable in a shift direction and in a select direction; a select lock unit which includes a shaft for limiting the select directional movement of the shift lever; and a controller which controls the select lock unit to limit the select directional movement of the shift lever on the basis of a gear shift stage. 
     When the gear shift stage corresponds to a predetermined gear shift stage, the controller may control the select lock unit to limit the select directional movement of the shift lever. 
     The predetermined gear shift stage may be a third gear or a fourth gear. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a shift control apparatus of a manual transmission according to an embodiment of the present invention; 
         FIG. 2  is a view showing a shift pattern marked on a knob surrounding a shift lever in the shift control apparatus of a manual transmission according to the embodiment of the present invention; 
         FIG. 3  is a plan view of the shift control apparatus of a manual transmission according to the embodiment of the present invention; 
         FIG. 4  is an exploded perspective view of the shift control apparatus of a manual transmission according to the embodiment of the present invention; 
         FIG. 5  is a cross sectional view of the shift control apparatus of a manual transmission according to the embodiment of the present invention; 
         FIG. 6  is a view showing a state where a select lock has been made in the shift control apparatus of a manual transmission according to the embodiment of the present invention; 
         FIG. 7  is a view showing a state where the select lock has been released in the shift control apparatus of a manual transmission according to the embodiment of the present invention; 
         FIG. 8  is a configuration view for describing the operation of solenoid of the shift control apparatus of a manual transmission according to the embodiment of the present invention; 
         FIG. 9  is a configuration view for describing the operation of a solenoid of the shift control apparatus of a manual transmission according to the embodiment of the present invention; and 
         FIG. 10  is a partial schematic view showing a main configuration of the shift control apparatus of a manual transmission according to the embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     The following detailed description of the present invention shows a specified embodiment of the present invention and will be provided with reference to the accompanying drawings. The embodiment will be described in enough detail that those skilled in the art are able to embody the present invention. It should be understood that various embodiments of the present invention are different from each other and need not be mutually exclusive. Similar reference numerals in the drawings designate the same or similar functions in many aspects. 
     Also, in the components of the present invention, detailed descriptions of what can be clearly understood and easily carried into practice by those skilled in the art will be omitted to avoid making the subject matter of the present invention unclear. 
       FIGS. 1 to 3  are views for describing a basic operation of a shift control apparatus of a manual transmission according to an embodiment of the present invention.  FIG. 1  is a perspective view of the shift control apparatus of a manual transmission according to the embodiment of the present invention.  FIG. 2  is a view showing a shift pattern marked on a knob surrounding a shift lever in the shift control apparatus of a manual transmission according to the embodiment of the present invention.  FIG. 3  is a plan view of the shift control apparatus of a manual transmission according to the embodiment of the present invention. 
     As shown in  FIG. 1 , basically, the shift control apparatus of a manual transmission according to the embodiment of the present invention includes a base bracket  10 , a shift lever  100 , and a select lever  200 . 
     The shift lever  100  is moved in a select direction or in a shift direction by the operation of a driver. The shift pattern shown in  FIG. 2  may be formed in a knob of the shift lever  100 . The driver controls a clutch (not shown) and the shift lever  100  in accordance with the speed of a vehicle, and changes the gear shift stage in accordance with the shift pattern. 
     Here, the following description will be provided by assuming that the gear shift stages that can be controlled by the shift control apparatus of a manual transmission according to the embodiment of the present invention are a total of six forward gear shifts of the first to sixth gear and a reverse gear shift of R gear. Also, it is apparent to those skilled in the art that the number of gear shift stages is not limited to this and a larger or smaller number of gear shift stages can be provided. 
     Generally, the transmission is installed between the clutch and final reduction gears/differential gears. The transmission changes the rotational torque and rotational speed of an engine and transfers to the final reduction gears/differential gears. 
     Transmission grading is as follows. A maximum shift ratio and a minimum shift ratio are determined by considering the maximum speed and climbing angle of the vehicle, and then the shift ratios of the medium gears are determined. Here, the shift ratio refers to each ratio of the gears at a point of time when the output of the engine, which has been generated by a crank shaft, is converted into a driving force within the transmission. 
     The driver controls the shift lever  100  and the clutch depending on the speed of the vehicle and changes the gear shift stage into a gear shift stage suitable for the speed. Each of the gear shift stages has its appropriate speed range. 
     For example, the first gear and the second gear are applied when the speed of the vehicle is less than approximate 40 km/h. The third gear and the fourth gear are applied the speed of the vehicle is approximate 40 km/h to 80 km/h. The fifth gear and the sixth gear are applied the speed of the vehicle is greater than approximate 80 km/h. Furthermore, according to the specification of the vehicle, the appropriate speed corresponding to each of the gear shift stages may be set to be different from that described above. 
     The driver should move the shift lever  100  in up, down, right and left directions shown in the shift pattern of  FIG. 2  so as to change the gear shift stage. Here, the right and left direction of the shift pattern of  FIG. 2  is referred to as the select direction, and the up and down direction is referred to as the shift direction. 
     When the speed of the vehicle traveling at the second gear speed increases and reaches a speed corresponding to the third gear, the driver steps on the clutch pedal and moves the shift lever  100  to the position  3  in the shift pattern. 
     Furthermore, when the speed increases and reaches a speed corresponding to the fourth gear, the driver steps on the clutch pedal and moves the shift lever  100  to the position  4  in the shift pattern. 
     As such, the driver cannot change the gear shift stage from the first gear to the sixth gear or to R gear by moving the shift lever  100  in the select direction or in the shift direction. 
     When the driver moves the shift lever  100  in the select direction (in S R  and S L  directions shown in  FIG. 1 ), the select lever  200  performs a rotational motion about a rotational axis (in an R direction in  FIG. 1 ). 
     The operations of the shift lever  100  and the select lever  200  will be described in more detail with reference to  FIGS. 4 and 5 . 
       FIG. 4  is an exploded perspective view of the shift control apparatus of a manual transmission according to the embodiment of the present invention.  FIG. 5  is a cross sectional view of the shift control apparatus of a manual transmission according to the embodiment of the present invention. 
     As shown in  FIGS. 4 and 5 , the shift lever  100  includes a rod  110 , a knob  120 , a ball shaft  130 , and a connecting rod  140 . 
     The knob  120  is provided on one end of the rod  110  for controlling the transmission. The shift pattern is, as shown in  FIG. 2 , formed in the knob  120 . The knob  120  makes it more convenient to control the transmission and may be made of a variety of materials in various shapes. 
     The ball shaft  130  is connected to the other end of the rod  110 . Also, the connecting rod  140  is connected to the other end of the rod  110  perpendicularly to the longitudinal direction of the rod  110 . One end of the connecting rod  140  is connected to the ball shaft  130 . The other end of the connecting rod  140  is connected to the select lever  200 . 
     The driver holds the knob  120  and moves the shift lever  100  in the select direction (in S R  or S L  direction), the spherical ball shaft  130  connected to the rod  110  performs a rotational motion about the center thereof 
     In response to this, the connecting rod  140  connected to the ball shaft  130  performs a rotational motion on the circumference about the center of the ball shaft  130 . The select lever  200  connected to the other end of the connecting rod  140  performs a rotational motion about the rotational axis thereof (in the R direction). 
     That is, the rotational motion of the select lever  200  is accompanied by the select directional movement of the shift lever  100 . 
       FIGS. 6 and 7  are views for describing a select lock operation of the shift control apparatus of a manual transmission according to the embodiment of the present invention. Specifically,  FIG. 6  is a view showing a state where a select lock has been made in the shift control apparatus of a manual transmission according to the embodiment of the present invention.  FIG. 7  is a view showing a state where the select lock has been released in the shift control apparatus of a manual transmission according to the embodiment of the present invention. Here, the select lock operation refers to an operation to block or allow the movement of the shift lever  100  by blocking the movement of the select lever  200 . 
     The shift control apparatus of a manual transmission according to the embodiment of the present invention further includes a select lock unit  300  and a controller  500  as well as the above-described shift lever  100  and the select lever  200 . 
     The select lock unit  300  functions to prevent that the shift lever  100  is shifted to R gear by the mal-operation of the driver while the vehicle travels at a high speed. 
     As described above, the driver changes the gear shift stage by operating the shift lever  100 . Here, only when the shift lever  100  is appropriately moved in the select direction and in the shift direction, the driver can change the gear shift stage into his/her desired gear shift stage. 
     In the case where the driver moves the shift lever  100  from the third gear/fourth gear to the fifth gear/sixth gear, there occurs a problem when the shift lever  100  is moved to the R gear position beyond the fifth gear position/sixth gear position by the mal-operation of the driver. In this case, an excessive force is added and thus overload is generated in the transmission. 
     When the shift lever  100  is moved from the third gear/fourth gear to the fifth gear/sixth gear, the select lock unit  300  according to the embodiment of the present invention blocks the shift lever  100  from moving to the R gear position in the select direction, thereby preventing in advance the above problem. 
     The select lock unit  300  includes a solenoid composed of a permanent magnet and a coil, and a current supply unit for supplying current to the coil of the solenoid. Here, the permanent magnet is fixed to the shaft either directly or indirectly. 
     The controller  500  controls the current which is supplied to the select lock unit  300  and produce a magnetic field, and thus, moves the shaft provided within the solenoid. 
     Particularly, the controller  500  performs the above operation on the basis of the vehicle&#39;s speed or the gear shift stage. That is, on the basis of the vehicle&#39;s speed or the gear shift stage, the controller  500  controls the current which is supplied to the select lock unit  300  and moves the shaft provided within the solenoid, and thus, causes the select lock unit  300  to perform or release the select lock operation. 
     First, the select lock operation of the select lock unit  300  will be described based on the speed of the vehicle. The controller  500  controls the select lock unit  300  on the basis of the speed of the vehicle. 
     Specifically, when the speed of the vehicle is in a speed range corresponding to the third gear or the fourth gear (e.g., 40 km/h to 80 km/h), the controller  500  causes the select lock unit  300  to block the shift lever  100  from moving in the select direction, in order to prevent the shifting lever from being moved to R gear by the mal-operation of the driver. 
     The controller  500  may receive information on the speed of the vehicle from an electronic control unit (ECU)  600 . 
     The electronic control unit  600  receives information from various sensors and is configured to operate various circuits and systems. In order that the engine is operated with the optimal performance in response to all the operation states of the vehicle, the electronic control unit  600  receives input signals from the various sensors and calculates an optimal amount of fuel injection, fuel injection timing, ignition timing, air amount, etc., which are based on each of the driving conditions and have an important influence on the drivability of the vehicle, exhaust gas, fuel efficiency, etc. Through this, the controller  500  functions to control the engine through an actuator such as an injector, ignition coil, etc. The electronic control unit  600  can sense the speed of the vehicle through various sensors. 
     The select lock operation of the select lock unit  300  will be described based on the gear shift stage. When the gear shift stage is the third gear or the fourth gear, the controller  500  causes the select lock unit  300  to block the shift lever  100  from moving in the select direction, in order to prevent the shifting lever from being moved to R gear by the mal-operation of the driver. 
     Here, a separate device for detecting information on the gear shift stage may be further included. The gear shift detection device (not shown) can detect the change of the gear shift in real time by using a physical method and an electronic method. Since a variety of known methods can be used in this, a detailed description thereof will be omitted. 
       FIG. 6  is a view showing a state where the select lock has been made in the shift control apparatus of a manual transmission according to the embodiment of the present invention. 
     As the shift lever  100  moves in the select direction, the select lever  200  performs a rotational motion about the rotational axis thereof. However, when the select lock is made, a shaft  310  of the select lock unit  300  comes to protrude, and the protruding shaft  310  is inserted into a locking groove  210  formed in the select lever  200 . As a result, the rotation of the select lever  200  is blocked. 
     Therefore, the driver is not able to move the shift lever  100  to the R gear position. 
     In other situations other than the above situation, the controller  500  causes the select lock unit  300  to release the select lock. Referring to  FIG. 7  showing the state where the select lock has been released, the shaft  300  of the select lock unit  300  is restored to the original state, and thus, the select lever  200  can freely rotate again. 
     As a result, the driver is able to move the shift lever  100  to the R gear position in the select direction. 
     Hereafter, the structure and operation of the select lock unit  300  and the operation of the controller  500  controlling the operation of the select lock unit  300  will be described with reference to  FIGS. 8 and 9 . 
     The select lock unit  300  which is one component of the shift control apparatus of a manual transmission according to the embodiment of the present invention includes, as shown in  FIGS. 8 and 9 , the shaft  310 , a permanent magnet  320 , and a coil  330 . A current supply unit  340  is connected to the coil  330 . The current supply unit  340  supplies the current to the coil  330 . 
     The permanent magnet  320  is fixed to the shaft  310 . In the embodiment of the present invention, a first permanent magnet  320 - 1  and a second permanent magnet  320 - 2  are fixed in the longitudinal direction of the shaft  310  in such a manner as to generate a repulsive force to each other. 
     That is to say, as shown in  FIGS. 8 and 9 , a magnetization direction of the first permanent magnet  320 - 1  is opposite to a magnetization direction of the second permanent magnet  320 - 2 . Also, one permanent magnet may be used instead of the two permanent magnets. 
     When the current is applied to the coil  330 , a magnetic field is formed around the select lock unit  300 .  FIG. 8  shows that an area where the first permanent magnet  320 - 1  is located within the solenoid is magnetized to N pole and an area where the second permanent magnet  320 - 2  is located within the solenoid is magnetized to S pole. 
     Here, since a repulsive force acts between the area magnetized to N pole and the N pole of the first permanent magnet  320 - 1 , they push each other. Contrary to this, since an attractive force acts between the area magnetized to S pole and the N pole of the second permanent magnet  320 - 2 , they pull each other. 
     Therefore, the permanent magnets  320 - 1  and  320 - 2  move, and then the shaft  310  to which the permanent magnets  320 - 1  and  320 - 2  have been fixed move together. In  FIG. 8 , the shaft  310  moves in the S pole magnetized direction, that is, in a direction further away from the select lever  200 . 
     When the shaft  310  moves, as shown in  FIG. 8 , in a direction further away from the select lever  200 , the select lock is released. In other words, since the shaft  310  comes out of the locking groove  210  of the select lever  200 , the select lever  200  is able to freely rotate. This means that the driver is able to move the shift lever  100  to the R gear position in the select direction. 
     Regarding the select lock release state, when the controller  500  determines that the current speed of the vehicle is not a speed corresponding to the third gear or fourth gear or the gear shift stage does not correspond to the third gear or fourth gear, the controller  500  controls the select lock unit  300  to cause the shaft  310  not to protrude. 
     Contrary to this, when the controller  500  determines that the current speed of the vehicle is a speed corresponding to the third gear or fourth gear or the gear shift stage corresponds to the third gear or fourth gear, the controller  500  controls the select lock unit  300  to creates the select lock state where the shaft  310  protrudes. 
     The select lock state can be made by supplying the current to the coil  330  of the select lock unit  300  in a direction opposite to the direction in which the current has been applied. In other words, the controller  500  supplies the current in a direction opposite to that of  FIG. 8 , and thus, forming the magnetic field within the solenoid in the opposite direction. This operation is shown in  FIG. 9 . 
     The direction in which the current flows through the coil  330  in  FIG. 9  is opposite to the current direction shown in  FIG. 8 . Due to the opposite current direction, the opposite magnetic field is formed within the solenoid. Meanwhile, since the structure of the shaft  310  is the same as that of the permanent magnet  320 - 1  and  320 - 2 , the permanent magnets  320 - 1  and  320 - 2  move in a direction opposite to the shaft  310 , and thus, the shaft  310  also moves in a direction opposite to that of  FIG. 8 . 
     Specifically, an attractive force acts between the area of the solenoid, which has been magnetized to S pole, and the N pole of the first permanent magnet  320 - 1 . A repulsive force acts between the area of the solenoid, which has been magnetized to N pole, and the N pole of the second permanent magnet  320 - 2 . 
     Therefore, the permanent magnets  320 - 1  and  320 - 2  move upward in  FIG. 9  and the shaft  310  moves together and protrudes outward. 
     When the shaft  310  moves and protrudes in the outward direction of the select lock unit  300 , the shaft  310  is, as shown in  FIG. 6 , inserted into the locking groove  210  of the select lever  200 . 
     As a result, the rotation of the select lever  200  is blocked. This means that the driver is not able to move the shift lever  100  to the R gear position in the select direction. 
     As such, the controller  500  controls the select lock unit  300  on the basis of the vehicle&#39;s speed and the gear shift stage, thereby blocking or allowing the movement of the shift lever  100  to R gear. Accordingly, the driver cannot move the shift lever  100  to R gear while the vehicle travels at a high speed, so that it is possible to prevent failures or accidents in advance. 
       FIG. 10  is a partial schematic view showing an enlarged configuration of the shift control apparatus of a manual transmission according to the embodiment of the present invention. In  FIG. 10 , the functions and structures of the base bracket  10 , the shift lever  100 , the select lever  200 , the select lock unit  300 , and the shaft  310  are the same as the above description. Therefore, repetitive description thereof will be omitted. 
     However, the shift control apparatus of a manual transmission according to the embodiment of the present invention may further include a position sensing magnet  350  and a magnetic field sensor  400 . 
     The position sensing magnet  350  may be provided on the end of the shaft  310  which is one component of the select lock unit  300 . 
     By the operation of the select lock unit  300  according to the control of the controller  500 , the magnetic field sensor  400  functions to sense whether the select directional movement of the shift lever  100  is limited or not. 
     More specifically, on the basis of the magnetic field change depending on the distance change of the position sensing magnet  350  provided on the end of the shaft  310 , the magnetic field sensor  400  senses the position of the shaft  310 . As a result, it is possible to recognize whether the select lock is made or released. 
     The magnetic field sensor  400  may be composed of a hall integrated circuit (IC). The hall IC is a magnetic sensor which measures the direction or intensity of the magnetic field by using a hall effect. 
     The magnetic field sensor  400  is located apart from the position sensing magnet  350  by a certain distance on the same line. Through the intensity of the magnetic field, the magnetic field sensor  400  measures the distance change of the position sensing magnet  350  depending on the movement of the shaft  310 . 
     In accordance with the above-described principle, the magnetic field sensor  400  can determine whether the select lock has been made or not. 
     In the meantime, the controller  500  can efficiently control the select lock unit  300  by using information on the select lock sensed by the magnetic field sensor  400 . 
     Also, information on the select lock state sensed by the magnetic field sensor  400  (information on the position of the shaft  310 ) is transferred to the electronic control unit  600  and may be usefully used in driving the vehicle. 
     Although embodiments of the present invention were described above, these are just examples and do not limit the present invention. Further, the present invention may be changed and modified in various ways, without departing from the essential features of the present invention, by those skilled in the art. For example, the components described in detail in the embodiments of the present invention may be modified. Further, differences due to the modification and application should be construed as being included in the scope and spirit of the present invention, which is described in the accompanying claims.