The well-known lifting jacks consist of a mechanical or hydraulic lifting mechanism driven by a hand. They are an additional equipment of the car and are loosely transported in a car luggage boot.

It is an object of the present invention to provide a lifting jack which can be used more easily and it is safer to operate by a driver.

The lifting jack according to the present invention consists of a lifting mechanism fixedly attached to a car frame and driven by a driving unit.

The lifting mechanism can comprise an oil pressure cylinder located inside a side-post of the car frame. The oil pressure cylinder can have a cylinder sleeve bolted via a base element to the car frame by means of bolts and a piston being slidable within the cylinder sleeve and ended with a foot and protruding through an opening in a floor of the car frame. The driving unit can be a hydraulic driving unit.

The lifting mechanism can consist of an oil pressure cylinder having a cylinder sleeve being a part of a side-post of the car frame and a piston being slidable within the cylinder sleeve and ended with a foot and protruding through an opening in the car frame.

The lifting mechanism can be housed in a casing and can have a threaded rod, a worm-wheel provided with a central threaded opening engaged with the threaded rod and a motor driving a worm screw engaged with the worm-wheel. The worm-wheel can be rotatably mounted by means of bearings in the casing. The threaded rod can be furnished with a groove which engages with a protrusion to avoid rotation of the threaded rod. A foot can be pivotally mounted on a bottom end of the threaded rod.

The lifting mechanism can have a threaded rod, a worm-wheel provided with a central threaded opening engaged with the threaded rod and a motor driving a worm screw engaged with the worm-wheel. The worm-wheel can be rotatably mounted by means of bearings inside a side-post of the car frame.

The threaded rod can be furnished with a groove which engages with a protrusion to avoid rotation of the threaded rod. A foot can be pivotally mounted on an end of the threaded rod.

The lifting jack can have an oil pressure cylinder consisting of a cylinder sleeve pivotally attached to the car frame by means of brackets and pins located at both sides of a lower part of the cylinder sleeve and of a piston being slidable within the cylinder sleeve and protruding through an opening in the car frame and ended with a grip pivotally connected to an arm by means of a pin joint. The arm can be jointly attached to the car frame and can be ended with a support roll. The brackets can be attached to the car frame by means of bolts.

The lifting mechanism can have an oil pressure cylinder consisting of a cylinder sleeve jointly attached to the car frame and of a piston being slidable within the cylinder sleeve and extending through an opening in the car frame and ended with a grip pivotally connected to an arm by means of a pin joint.

The arm can be jointly attached to the car frame and can be ended with a support roll.

The lifting mechanism can consist of a worm-wheel, a rotary arm fixedly attached to the worm-wheel and a driving unit driven worm screw engaged with the worm-wheel. The rotary arm and the worm-wheel can be mounted in a casing which is attached to the car frame via bolts. The rotary arm can protrude outside the car frame through a slot.

The lifting mechanism can consist of a worm-wheel, a rotary arm fixedly attached to the worm-wheel and a worm screw engaged with the worm-wheel and driven by the driving unit formed by a motor or a crank handle. The rotary arm and the worm-wheel can be mounted inside a side-post. The rotary arm can extend outside the car frame through a slot.

The lifting mechanism can be housed in a casing supported on the car frame by means of bearings and can consist of a threaded rod extending through an opening in the car frame, a worm-wheel furnished with a central threaded opening engaged with the threaded rod, a worm screw engaged with the worm-wheel and driven by a motor. The worm-wheel can be rotatably mounted by means of bearings in the casing. The threaded rod can be furnished with a groove engaging with a protrusion and can be pivotally attached to a supporting arm by means of a grip and a shaft. The supporting arm can be pivotally connected at an upper end to the car frame and can have a support roll at a bottom end.

The lifting mechanism can consist of a threaded rod extending through an opening in the car frame, a worm-wheel furnished with a central threaded opening engaged with the threaded rod, a worm screw engaged with the worm-wheel and driven by a motor. The worm-wheel can be rotatably mounted by means of bearings inside a side-post. The threaded rod can be furnished with a groove engaging with a protrusion and is pivotally attached to a supporting arm by means of a grip and a shaft. The supporting arm can be jointly connected at an upper end to the car frame and can have a support roll at a bottom end.

The present invention is illustrated in preferable embodiments in the accompanying drawings in which fig. 1 schematically shows a car provided with a lifting jack and a driving unit, fig. 2 is a lifting jack with a hydraulic lifting mechanism bolted to a car frame shown schematically, fig. 3 is a lifting jack with a mechanical lifting mechanism bolted to a car frame, fig. 4 is a lifting jack with a moveable arm and a hydraulic lifting mechanism bolted to a car frame, fig. 5 is a lifting jack with a rotary arm and a mechanical lifting mechanism bolted to a car frame, fig. 6 is a lifting jack with a moveable arm and a me chanical lifting mechanism bolted to a car frame, fig. 7 is a lifting jack with a hydraulic lifting mechanism built into a car frame, fig. 8 is a lifting jack with a mechanical lifting mechanism built into a car frame, fig. 9 is a lifting jack with a moveable arm and a hydraulic lifting mechanism built into a car frame, fig. 10 is a lifting jack with a rotary arm and a mechanical lifting mechanism built into a car frame, fig. 11 is a lifting jack with a moveable arm and a mechanical lifting mechanism built into a car frame.

Fig. 1 shows a car frame 3 and a lifting mechanism 1 fixedly attached to the car frame 3 and located in a side-post 9. The lifting mechanism 1 is driven by a driving unit 2 and is shown schematically.

A lifting jack, as shown in Fig. 2, consists of a hydraulic lifting mechanism provided with an oil pressure cylinder 4 located in the side-post 9 of the car frame 3. The oil pressure cylinder 4 has a cylinder sleeve 81 and a piston 7 being slidable within the cylinder sleeve 81 and a base element 5 which is bolted to the car frame 3 by means of bolts 6. In one of the embodiments the cylinder oil pressure 4 can be furnished with a piston telescopically extendable out of the cylinder sleeve. The piston 7, which protrudes from the side-post 9 through an opening made in the floor of the car frame 3, is ended with a foot 8.

As illustrated in fig. 7, s sleeve cylinder 82 of the further embodiment is a part of a side-post 99. The piston 7 extends through an opening 85.

Fig. 3 shows a mechanical lifting mechanism 31 consisting of a threaded rod 10, a worm gear and a motor 32 housed in a casing 12. A worm- wheel 11 of the worm gear is provided with a central threaded opening 43 engaged with the threaded rod 10. The worm-wheel 11 is rotatably mounted by means of bearings 41 in the casing 12 and is driven by the motor 12 via a worm screw 44. Rotation of the worm-wheel 11 causes pushing the threaded rod 10 out of the side-post 9. The threaded rod 10 is furnished with a groove 14 which engages with a protrusion 54 to avoid its rotation. A foot 15 is pivotally mounted on the end of the threaded rod 10 thus the threaded rod 10 does not come in the ground.

As illustrated in fig. 8, the worm wheel 11 of the further embodiment is rotatably mounted by means of bearings 41 in the side-post 9.

Fig. 4 shows the further embodiment of the lifting jack. A cylinder sleeve 59 of an oil pressure cylinder 16 of this embodiment is pivotally attached to the floor of the car frame 3 by means of two brackets 18 and pins 19 located at both sides of a lower part of the oil pressure cylinder 16. The brackets 18 are attached to the floor by means of bolts 17. A piston 20, being slidable within the cylinder sleeve 59, is ended with a grip 51 and is pivotally connected to an arm 21 by means of a pin joint 25. The arm 21 is hinged to the car frame by means of an arm bracket 22 and an arm joint 26. The arm bracket 22 is fastened to the car frame 3 via bolts 23. After actuating the cylinder 16, its piston 20 forces the arm 21 downwards and lifts up the car. The arm 21 is ended with a support roll 24.

As illustrated in fig. 9, the cylinder sleeve 59 of the further embodiment is pivotally attached to a side-post 118 by means of a joint 119 and is actuated by a hydraulic driving unit 77.

As it is shown in fig. 5 the lifting jack consists of a rotary arm 30 which is fixedly attached to a worm-wheel 27. The worm-wheel 27 is engaged with a worm screw 61 driven by a motor 32. The rotary arm 30 and the worm-wheel 27 are rotatably mounted in a casing 28 which is attached to the car frame 3 via bolts 28. In the position shown, the arm 30 is in its downright position and extends through a slot 62 in a floor of the car frame 3. After actuating the motor 32, the arm 30 moves in the slot 62 and causes lowering the frame car 3. The arm 30 is ended with a support roll 31 to reduce the friction.

As illustrated in fig. 10, the rotary arm 30 of the further embodiment is pivotally attached to a side-post 9 by means of a joint 76.

Fig. 6 shows the lifting jack which is provided with a mechanical lifting mechanism housed in a casing 91 supported on casing bearings 43. The lifting mechanism consists of a threaded rod 37, a worm-wheel 71, a worm screw 33 and a motor 32. The worm-wheel 71 is furnished with a central threaded opening 72 engaged with the threaded rod 37. The worm-wheel 71 is rotatably mounted by means of bearings in the casing 34 and is driven by the motor 32 via the worm screw 33. When the worm-wheel 11 rotates, the threaded rod 37 is pushed out. To avoid rotation of the threaded rod 37 it is furnished with a groove 73 which engages with a protrusion 74. The threaded rod 37 is pivotally attached to a supporting arm 38 by means of a grip 75 and a shaft 42. The upper end of the supporting arm 38 is connected to the car frame 3 by means of a bracket 39 and a bracket bolt 40. The bracket 39 is fixed to the car frame 3 via bolts 36. A support roll 24 is mounted at the free end of the supporting arm 38.

As illustrated in fig. 11, a worm-wheel 71 of the further embodiment is rotatably mounted inside a side-post 9 by means of bearings 143.