Background Art Because there is limitation for the steering angle of the front wheel, in case of vehicle parking, additional space that is larger than minimum radius of rotation is needed. In order to solve such problem, several types of parking assistant systems have been developed. Most common technology lifting both front and rear wheel or one of them can be represented as below.

1. Lateral motion of the vehicle using left-and-right driving of the assistant wheel 2. Rotational motion of the vehicle around the central axis of the parking assistant Even though there are some differences in each system, basic fundamental of the parking assistant system is the lateral. and longitudinal motion applied separately to perform exact movement or rotational motion as driver's intention. This invention explains the reason that parking assistant system should be driven with separated motion so called exact left-and-right motion and exact up-and-down motion.

In case of conventional system, main focus have been concentrated on above two motion only. However there are still problems such as installation that can be reduced through the miniaturization, working efficiency absorbing weight of vehicle during lateral and longitudinal motion and driving safety regarding to the additional space between ground and vehicle. Also it doesn't have to effect to the power train.

Disclosure of Invention The purpose of this invention is to resolve main problems as described above so that it can be possible utilization of the parking assistant system commonly. The social problem that has being increased related to parking could be reduced using the system of parking assistant wheel with parallel motion links type.

Successful performance for the system can be carried out by means of manual control of a driver through the switch. Two reversing DC motors are in charge of exact left-and-right and up-and-down motion through the link mechanism.

Technical characteristics of the invention are as follow.

The system of parking assistant wheel with parllel motion links type comprising: The parallel motion links type that consists of the links (1~12), link blocks (13, 14), hollow rivets (15~30) are combined with shafts (31-39), warm gear (40), shaft of the screw gear type (41) and 2 reversing gear (72,73) ; The reversing DC motor (A) combined with the shaft (31) for system driving to make up-and-down motion; The reversing DC motor (B) combined with the shaft (39) for system driving to make left-and-right motion; The Assistant wheel (80) combined with shaft (35) for wheel driving; The revercing DC motor (A) and the parallel motion links type's combination that consists of The belt gear (50,51) combined with shaft (31) and warm type shaft (32) are connected with the belt (60); The reversing DC motor (B) and the assistant wheel (80)'s combination that consists of The 1 st belt gear (52,53) combined with the shaft (39) and shaft (38) are connected with the 1 S belt (61), the 2nd belt gear (54,55) combined with the shaft (37) and shaft (36) are connected with the 2nd belt (62), the 1"reversing gear (70,71) correspond with the shaft (38) and shaft (37); The driver's recognition device of system operating consist of the sound switch (90), nut (91) combined with the shaft (41) of screw gear type and speaker (92); The switch device (100) to impress the power to the reversing DC motor (A) and (B) respectively; the case device (110) functions bracket to install to the vehicle protecting from external disturbance; Brief Description of Drawings Fig. 1 Structural drawing of the system Fig. 2 Complete drawing of the system Fig. 3 Assembly drawing of the system for the case Fig. 4 Schematic diagram for the switch circuit Fig. 5 Operation diagram for the sound switch Fig. 6 Operation diagram Fig. 7 Installation diagram to the vehicle Fig. 8 Example diagram of the system for parking <Description of the main symbol on the drawings> A :. Reversing DC motor for an up-and-down motion B: Reversing DC motor for a left-and-right motion 1-12 : Links 13,14 : Link blocks 15~30 : Hollow rivet 31~39 : Shaft (31: For the A motor driving, 32: Warm type 35: For the wheel driving, 39: For the B motor driving) 40: Warm gear 41: Screw gear type shaft 5cl55 : Belt gear (50,51 : For the A driving, 52,53 : 1"gear for the B driving, 54,55 : 2nd gear for the B driving) 60~62 : Belt (60: For the A driving, 61: 1"be ! t for the B driving, 62: 2nd belt for the B driving) 70,71 : 15'reverse gear for the B driving 72,73 : 2nd reverse gear for the B driving 80 : Assistant wheel 90: Sound switch 91: Nut 92: Speaker 100 : Switch box 110: External case 120: Control relay Best Mode for Carring out the Invention System structure and its description are described with Fig. 1.

For easy understanding, each subcomponent is represented as below.

- Reversing DC motor for the longitudinal motion: A part - Reversing DC motor for the lateral motion: B part First, the links (1~12) are combined with the link blocks (13,14) through the hollow rivets (15~30) and shafts (31-39). Second, the shaft (41) of screw gear type joined with the warm gear (40) which correspond with warm type shaft (32) is combined between the link blocks (13, 14), and then the 2nd reversing gears (72,73) which correspond with the shafts (35,36) for the B driving is combined with links (4,10). Link block (14) is the nut corresponds with the shaft (41) of screw gear type.

Finally, parallel motion link's type that can convert rotational motion of the shaft (41) into parallel motion absorbing the vehicle weight similar with emergency jack for a vehicle is completed.

The A motor and B motor are combined with the shaft (31) for A motor driving and the shaft (39) for B motor driving respectively on the back side of the parallel motion links type. 1 S reversing gears (70,71) correspond with each other are combined with shafts (38,37), and then assistant wheel is combined with the shaft (35) for the wheel driving.

The Driving shaft (31) for the A motor and the warm type shaft (32) are combined with the driving belt gear (50,51), the driving shaft (39) for B motor and the shaft (38) are combined with the 1St gear (52,53) for B driving, the shaft (37) and (36) are combined with the 2nd gear (54,55) for B driving on front side of the parallel motion links type and then next sequence follows. The belt gear (50,51) for A driving, lut gear (52,53) for B driving, and 2nd gear (54,55) for B driving are put into the A driving belt (60), B driving belt (61) and 2 belt (62) for B driving respectively.

The sound switch (90) is installed outside of link block (14), this switch can perform by means of combining the screw gear shaft (41) and nut (91) as pull button.

The control relay (120) which energize the voltage and up-down button of the switch box (100) [This consist of two reversing switch circuit having parallel connection with battery voltage] are combined with the A motor terminal to protect from malfunction. As a result the system of parking assistant wheel with parallel motion links type is accomplished by means of combining the left-right button and speaker with the B motor terminal and sound switch respectively. Finally external case functions as a bracket is installed to the spare part of the vehicle underbody to protect from external disturbance. Fig. 2 shows the complete system.

Working process of the system follows - When a driver want to park, the A motor rotate counterclockwise driving the belt gear (50,51) and belt (60) with same direction by pushing'UP'button of the switch box.

- During counterclockwise rotation of the shaft (41) combined with the warm gear (40), the parallel motion makes contact of the assistant wheel and ground by screw motion with the link block (14) lifting front wheel of the vehicle.

- The speaker start to work as the nut (91) is separated from the sound switch installed external part of the link block (14), driver can recognize the start of the system operating.

- The driver should stop the'UP'button when the rising motion of the front wheel is finished with idle rotation of the shaft (41).

- For right movement of the vehicle, the 1 S belt gear (52,53) and B belt gear (61) for B driving are rotated counterclockwise by driving the shaft (39) for the B motor using'Right'button - The shaft (38) transmit clockwise rotation to 2""belt gear (54,55) and 2nd belt (62) for B driving through 1"reversing gear (70,71).

- Right movement of the vehicle can be performed with counterclockwise rotation of the assistant wheel through the 2nd reversing gear (72,73).

- For left movement of the vehicle, the lst belt gear (52,53) and B belt gear (61) for B driving are rotated clockwise by driving the shaft (39) for the B motor using'Left'button.

- Shaft (38) transmit counterclockwise rotation to the 2nd belt gear (54,55) and 2 belt (62) for B driving through 1"reversing gear (70,71).

- Left movement of the vehicle can be performed with clockwise rotation of the assistant wheel through the 2nd reversing gear (72,73).

- When the vehicle is located on the exact position, the belt gear (50,51) and belt (60) are rotated clockwise through the shaft (31) for A motor driving with the'DOWN'button, then the assistant wheel (80) is separated from the ground descending front wheel.

This movement can be achieved by means of screw motion with the shaft (41) of screw gear type.

- The sound switch (30) is pushed by the nut (91) combined with the shaft (41) of screw gear type, therefore the driver can recognize the end of the system operating.

- It is possible to control the parking assistant system with wide range of degree of freedom and safety compared with sequence control. This can be achieved by the control relay (120) in the switch box (100) and speaker (92) Therfore'The system of parking assistant wheel with parallel motion links type'can make a solution regarding to installation to the vehicle, working efficiency and driving safety. It is possible to utilize parking assistant system needed to resolve parking problem with an exact left-and-right and up-and-down motion.