Lifting jack for automotive

1. A lifting jack for an automotive, comprising:

a base;

a pair of lower arms of which a first end portion is pivotally engaged with a first side and a second side of the base;

a stand having a stand groove;

a pair of upper arms of which a first end portion is pivotally engaged with a first side and a second side of the stand and a second end portion is pivotally engaged with a second end portion of the pair of lower arms;

a fix bracket pivotally engaged with the second end portion of one of the pair of lower arms and the second end portion of one of the pair of upper arms;

a hollow screw rod penetrating and being inserted into the fix bracket wherein screw threads are provided on an external circumference thereof;

a connection shaft inserted into an internal circumference of the screw rod; and

a key inserted into the screw rod through the fix bracket wherein the connection shaft is inserted into and fixed at the internal circumference of the screw rod.

2. The lifting jack for the automotive of claim 1 , wherein

the second end portion of the pair of lower arms is pivotally engaged with an external side of the second end portion of the pair of upper arms.

3. The lifting jack for the automotive of claim 1 , wherein

the fix bracket is pivotally engaged with an internal side of one of the pair of upper arms.

4. The lifting jack for the automotive of claim 1 , wherein

screw grooves are provided at the internal circumference of the screw rod.

5. The lifting jack for the automotive of claim 4 , wherein

shaft protrusions engaged with the screw grooves are provided at an external circumference of the connection shaft.

6. The lifting jack for the automotive of claim 5 , wherein

the connection shaft rotates in a direction which is vertical to a lengthwise direction of the connection shaft wherein the screw grooves and the shaft protrusions are engaged with each other.

7. The lifting jack for the automotive of claim 6 , wherein

key protrusions are provided at an external circumference of the key, and

the key protrusions are inserted between and engaged with the shaft protrusions.

8. The lifting jack for the automotive of claim 7 , wherein

the key is inserted into the screw rod through the fix bracket in state that the key rotates in a direction vertical to a lengthwise direction of the connection shaft and the screw grooves and the shaft protrusions are engaged with each other.

9. The lifting jack for the automotive of claim 8 , wherein

the base and the stand are remote from each other by rotating the connection shaft in an opposite direction to rotation direction which the screw grooves and the shaft protrusions are engaged with each other.

10. The lifting jack for the automotive of claim 8 , wherein

the base and the stand are remote from each other by rotating the key in an opposite direction to a rotation direction which the screw grooves and the shaft protrusions are engaged with each other.

11. The lifting jack for the automotive of claim 8 , wherein

a key hole is provided at an end portion of the key in an opposite direction to a direction which the key is inserted into the screw rod.

12. The lifting jack for the automotive of claim 11 , wherein

the key rotates by inserting a wrench into the key hole and rotating the wrench.

13. The lifting jack for the automotive of claim 11 , wherein

the key hole and the fix bracket are connected to each other by a chain.

14. The lifting jack for the automotive of claim 6 , wherein

a connection shaft hole is provided at an end portion of the connection shaft in an opposite direction to a direction which the connection shaft is inserted into the internal surface of the screw rod.

15. The lifting jack for the automotive of claim 14 , wherein

the connection shaft rotates by inserting a wrench into the connection shaft hole and rotating the wrench.