Abstract:
Disclosed herein is an automatically operated antiskid apparatus for automobile tires. The automatically operated antiskid apparatus includes an operating signal generating unit for transmitting an operating signal generated by a bar operating switch to positions in the vicinity of automotive wheels. A signal transmitting unit receives the operating signal from the operating signal generating unit and transmits the operating signal from a stationary automobile body to rotating wheel rims. An antiskid bar and antiskid bar operating unit receives the operating signal from the signal transmitting unit and operates antiskid bars embedded in tread portions of the tires.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates generally to automatically operated antiskid apparatus for automobile tires, and more particularly to automatically operated antiskid apparatus for automobile tires, which is capable of projecting antiskid bars from the circumferential surfaces of automobile tires by manipulating a bar operating switch from the interior of an automobile so as to drive the automobile on a snowy or icy road.  
           [0003]    2. Description of the Prior Art  
           [0004]    In present-day life, automobiles are indispensably utilized for obtaining satisfactory mobility, and a demand for automobiles is continuously increasing. The safety of a driver greatly depends on weather conditions and external environments while he drives an automobile. In general, when an automobile is started, driven and braked on a snowy or icy road, antiskid apparatuses for automobile tires, such as tire chains, are utilized so as to prevent the automobile tires from skidding on such a road.  
           [0005]    That is, in the winter season, in order to provide for snowy weather and a snowy or icy road, drivers put tire chains made of steel around automobile tires, clamp them together, and tighten them using rubber strings before or while driving.  
           [0006]    In order to eliminate inconvenience caused by the conventional tire chains that should be put around tires, clamped together and tightened by drivers, there are developed and merchandised improved antiskid apparatuses that are easily operated and lightweight.  
           [0007]    However, the conventional improved antiskid apparatuses are problematic, in that the antiskid apparatuses should be mounted on automobile tires and demounted from the tires by drivers&#39; physical effort, it is difficult to mount antiskid apparatuses on automobile tires in advance so as to provide against snowy or icy areas that are occasionally met, and unskilled drivers should spend excessive time in mounting the antiskid apparatuses on the automobile tires and demounting the antiskid apparatuses from the automobile tires.  
         SUMMARY OF THE INVENTION  
         [0008]    Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide an automatically operated antiskid apparatus for automobile tires, which is capable of selectively projecting antiskid bars from the circumferential surfaces of the automobile tires and retracting the antiskid bars into the tires by manipulating a bar mounting switch at a driver&#39;s seat so as to drive the automobile on a snowy or icy road and a dry road.  
           [0009]    In order to accomplish the above object, the present invention provides an automatically operated antiskid apparatus for automobile tires, comprising: an operating signal generating unit for transmitting an operating signal generated by a bar operating switch to positions in the vicinity of automotive wheels; a signal transmitting unit for receiving the operating signal from the operating signal generating unit and transmitting the operating signal from a stationary automobile body to rotating wheel rims; and an antiskid bar and antiskid bar operating unit for receiving the operating signal from the signal transmitting unit and operating antiskid bars embedded in tread portions of the tires.  
           [0010]    In accordance with a first embodiment of the present invention, the signal generating unit consists of the bar operating switch, a booster connected to the bar operating switch for amplifying the operating signal, a hydraulic cylinder connected to the booster for transmitting an amplified operating signal, a hydraulic conduit connected to the hydraulic cylinder for transmitting the amplified operating signal, and a plurality of hydraulic pistons connected to the hydraulic conduit and mounted on knuckles situated in the middle of the tires; the signal transmitting unit consists of a plurality of divided bearings each attached to a plurality of guide portions formed on inside surfaces of wheel rims, each of the divided bearings being composed of left and right disks and bearing balls between right and left disks; the antiskid bar and antiskid bar operating unit consists of a plurality of steel wire pulling pieces each situated outside of each divided bearing, a plurality of steel wires first ends of which are connected to the steel wire pulling pieces, and a plurality of antiskid bar units connected to second ends of the steel wires and positioned in tread portions of the tires; and each of the antiskid bar units consists of a T-shaped, hollow casing part made of flexible, thin material and provided with a plurality of vertical guide slots, a guide part provided with a plurality of inclined guide slots and at its both sides with one or more springs, and a bar part provided with a plurality of projections and situated between two members of the guide part with the projections inserted into the inclined slots of the guide part.  
           [0011]    In accordance with a second embodiment of the present invention, the signal generating unit consists of the bar operating switch, and a plurality of electric wires first ends of which are connected to the bar operating switch and second ends of which are connected to the hubs, each of the electric wires being comprised of a pair of wire strands; the signal transmitting unit consists of a plurality of divided bearings, each of the divided bearings being comprised of inside and outside bearings and a plurality of balls, the inside bearing being mounted on a hub and provided with two contacts each surrounded with intercepting material, the outside bearing being mounted not to be rotated, first central terminals of the wire strands of each electric wire passing through the outside bearing and being brought into contact with the contacts formed on the inside bearing, second central terminals of the wire strands of each electric wire passing through the inside bearing and the intercepting material and being connected to the contacts formed on the inside bearing; the antiskid bar and antiskid bar operating unit in which second ends of the electric wires are connected to electromagnets positioned in the casing parts of a plurality of electromagnetic antiskid bar units so that guide parts are moved to project bar parts by moving permanent magnets attached to the side protrusions of the guide parts; and each of the electromagnetic type antiskid bar units consists of the T-shaped, hollow casing part made of flexible, thin material and provided in its interior with four fixed electromagnets and a plurality of vertical guide slots, the guide part provided with a plurality of inclined guide slots and at its both sides with two permanent magnets, and the bar part provided with a plurality of projections and situated between two members of the guide part with the projections inserted into the inclined slots of the guide part.  
           [0012]    In accordance with a third embodiment of the present invention, the signal generating unit consists of the block operating switch, and a plurality of electric wires first ends of each of which are connected to the block operating switch and second ends of each of which are connected to a hub, each of the electric wires being comprised of a pair of wire strands; the signal transmitting unit consists of a plurality of divided bearings, each of the divided bearings being comprised of inside and outside bearings and a plurality of balls, the inside bearing being mounted on a hub and provided with two contacts each surrounded with intercepting material, the outside bearing being mounted not to be rotated, first central terminals of the wire strands of each electric wire passing through the outside bearing and being brought into contact with the contacts formed on the inside bearing, second central terminals of the wire strands passing through the inside bearing and the intercepting material and being connected to the contacts formed on the inside bearing; the antiskid block and antiskid block operating unit in which the second ends of the electric wires are connected to coils positioned in the casing parts of electromagnetic type circular antiskid block units embedded in the tread portions of tires so that the guide parts are moved to project block parts by moving permanent magnets attached to side protrusions of the guide part: and each of the electromagnetic circular antiskid block units consists of the cylindrical casing part which is made of rubber and in which a coil, to which the wire is connected, is situated, the cylindrical guide part positioned inside of the casing part and provided with a plurality of inclined guide slots, and the block part positioned inside of the guide part and provided at its outside surface with a plurality of projections inserted into the guide slots. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]    The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:  
         [0014]    [0014]FIG. 1 is a perspective view showing an operating signal generating unit of an automatically operated antiskid apparatus for automobile tires in accordance with the present invention;  
         [0015]    [0015]FIG. 2 is a flowchart showing the operation of the automatically operated antiskid apparatus for automobile tires;  
         [0016]    [0016]FIG. 3 is a partial sectional view showing the operation of an automatically operated antiskid apparatus of a first embodiment in which a hydraulic piston pushes a divided bearing;  
         [0017]    [0017]FIG. 4 is a partial sectional view showing the operation of the automatically operated antiskid apparatus of the first embodiment in which the hydraulic piston is moved rearward and the divided bearing is returned to its original position by the action of spring bars;  
         [0018]    [0018]FIG. 5 is a partial sectional view showing the automatically operated antiskid apparatus of the first embodiment in which a plurality of hydraulic pistons and the divided bearing are arranged on a wheel rim;  
         [0019]    [0019]FIG. 6 is a sectional view showing the automatically operated antiskid apparatus of the first embodiment in which the antiskid bar unit embedded in the tread portion of a tire is connected to the steel wire;  
         [0020]    [0020]FIG. 7 is a perspective view showing the assembly of an antiskid bar unit of the first embodiment in which a divided guide part and a bar part are inserted into a hollow, T-shaped casing part;  
         [0021]    [0021]FIG. 8 is a perspective view showing the operation of the antiskid bar unit of the first embodiment in which projections formed on the bar part are moved along inclined guide slots formed through the guide part while the projections are inserted into the inclined guide slots;  
         [0022]    [0022]FIG. 9 is a partial sectional view showing an automatically operated antiskid apparatus of a second embodiment, in which electric wires are connected to a divided bearing;  
         [0023]    [0023]FIG. 10 is an exploded perspective view showing the electromagnetic type antiskid bar unit of the automatically operated antiskid apparatus of the second embodiment;  
         [0024]    [0024]FIG. 11 is a partial sectional view showing an automatically operated antiskid apparatus of a third embodiment in which electric wires are connected to a divided bearing;  
         [0025]    [0025]FIG. 12 is an exploded perspective view showing the construction of the electromagnetic type circular antiskid bar unit of the third embodiment;  
         [0026]    [0026]FIG. 13 is a vertical cross-section showing the assembly of the electromagnetic type circular antiskid bar unit of the third embodiment; and  
         [0027]    [0027]FIG. 14 is a plan view showing the assembly of the electromagnetic type circular antiskid bar unit of the third embodiment. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0028]    Reference now should be made to the drawings, in which the same reference numerals are used throughout the different drawings to designate the same or similar components.  
         [0029]    [0029]FIG. 1 is a perspective view showing an operating signal generating unit of an automatically operated antiskid apparatus for automobile tires in accordance with the present invention. In this drawing, when a driver manipulates a bar operating switch  7  situated in the vicinity of a driver&#39;s seat, an operating signal is transmitted to a booster so that a hydraulic cylinder supplies hydraulic oil through a hydraulic conduit  2 , thus supplying hydraulic oil toward the wheel rims.  
         [0030]    [0030]FIG. 2 is a flowchart showing the operation of the automatically operated antiskid apparatus for automobile tires. In this flowchart, the operation of the operating signal generating unit, a signal transmitting unit and an antiskid bar and antiskid bar operating unit are described in sequence.  
         [0031]    [0031]FIG. 3 is a partial sectional view showing the operation of an automatically operated antiskid apparatus of a first embodiment in which a hydraulic piston  5  pushes a divided bearing  10 . The divided bearing  10  and a steel wire pulling piece  27  are pushed to the right by the forward movement of the hydraulic piston  5 . In this drawing, a connection between the steel wire pulling piece  27  and the steel wire  28  is covered with a bellows tube  15  so as to prevent the connection from being polluted by pollutants, such as dust.  
         [0032]    [0032]FIG. 4 is a partial sectional view showing the operation of the automatically operated antiskid apparatus of the first embodiment in which the hydraulic piston is moved rearward and the divided bearing is returned to its original position by the action of spring bars  14 . In this drawing, if a driver manipulates the bar operating switch  7  when antiskid bars are not desired to be utilized, the hydraulic piston  5  is moved rearward and the divided bearing  10  is returned to its original position by the action of two spring bars  14 . In this case, the steel wire pulling piece  27  is returned to its original position by the action of the spring  24  of an antiskid bar unit  20 .  
         [0033]    [0033]FIG. 5 is a partial sectional view showing the automatically operated antiskid apparatus of the first embodiment in which a plurality of hydraulic pistons  5  and the divided bearing  10  are arranged on a wheel rim. In this drawing, the divided bearing  10  is fixedly held by a plurality of guide portions  4  formed on the inside surfaces of wheel rims and a plurality of hydraulic pistons  5  are arranged at regular intervals.  
         [0034]    [0034]FIG. 6 is a sectional view showing the automatically operated antiskid apparatus of the first embodiment in which the antiskid bar unit  20  embedded in the tread portion of a tire is connected to the steel wire  28 . In this drawing, the connection of the antiskid bar unit  20  and the steel wire  28  is illustrated in detail.  
         [0035]    [0035]FIG. 7 is a perspective view showing the assembly of the antiskid bar unit of the first embodiment in which a divided guide part  22  and a bar part  21  are inserted into a hollow, T-shaped casing part  23 .  
         [0036]    [0036]FIG. 8 is a perspective view showing the operation of the antiskid bar unit of the first embodiment in which projections  29  formed on the bar part  21  are moved along inclined guide slots  26  formed through the guide part  22  while the projections  29  are inserted into the inclined guide slots  26 .  
         [0037]    [0037]FIG. 9 is a partial sectional view showing an automatically operated antiskid apparatus of a second embodiment, in which electric wires are connected to a divided bearing. In this drawing, in order to connect electric wires from a stationary automobile body to rotated hubs, the first central terminals  31  and  32  of the wire strands of each wire pass through an outside bearing  61  and are brought into contact with contacts  64  formed on an inside bearing  61 , while the second central terminals  33  and  34  of the wire strands of each wire pass through the inside bearing  61  and intercepting material  65  and are connected to the contacts  64  formed on the inside bearing  61 .  
         [0038]    [0038]FIG. 10 is an exploded perspective view showing the electromagnetic type antiskid bar unit of the automatically operated antiskid apparatus of the second embodiment. In this drawing, electric wires  30  are connected to electromagnets  44  inserted into the casing part  43  of the electromagnet type bar supply unit  40  embedded in the tread portions  51  of the tires and permanent magnets  45  are formed on the side protrusions of a divided guide part  42 .  
         [0039]    [0039]FIG. 11 is a partial sectional view showing an automatically operated antiskid apparatus of a third embodiment, in which electric wires are connected to a divided bearing. The construction and operation of the electric wires and the bearing are identical to the construction and operation of the electric wires and the bearing of the FIG. 9.  
         [0040]    [0040]FIG. 12 is an exploded perspective view showing the electromagnetic type circular antiskid bar unit of the third embodiment, in which a bar part  71  provided at the outer surface thereof with a plurality of projections  75  is situated inside of a guide part  72  provided with a plurality of inclined guide slots  76  and the guide part  72  is situated inside of a casing part  73  through which a coil  74  connected to an electric wire  30  is positioned.  
         [0041]    [0041]FIG. 13 is a vertical cross-section showing the electromagnetic type circular antiskid bar unit of the third embodiment with the projections  75  formed on a bar part  71  inserted into the inclined guide slots  76  formed through the guide part  72 .  
         [0042]    [0042]FIG. 14 is a plan view showing the electromagnetic type circular antiskid bar unit of the third embodiment with the coil  74  contained in the casing part  73  connected to the electric wire  30 .  
         [0043]    Hereinafter, the automatically operated antiskid apparatus in accordance with embodiments of the present invention is described in detail.  
       Embodiment 1  
       [0044]    In this embodiment, there is disclosed an apparatus for operating antiskid bar units  20  embedded in the tread portions of automobile tires by manipulating a bar operating switch  7  in a hydraulic manner. The automatically operated antiskid apparatus of this embodiment is comprised of a operating signal generating unit, a signal transmitting unit and an antiskid bar and antiskid bar operating unit. The signal generating unit consists of the bar operating switch  7 , the booster, the hydraulic cylinder, the hydraulic conduit  2 , and a plurality of hydraulic pistons  5 . The signal transmitting unit consists of a divided bearing  10 . The antiskid bar and antiskid bar operating unit consists of a plurality of steel wire pulling pieces  27 , a plurality of steel wires  28  and a plurality of antiskid bar units  20 .  
         [0045]    The operation of the automatically operated antiskid apparatus in accordance with this embodiment is described hereinafter. As illustrated in FIG. 1, when a driver transmits an operating signal by manipulating the bar operating switch  7  because it is desired to be utilized to operate the antiskid bars for the automobile tires, the booster and the hydraulic cylinder are operated. Hydraulic pressure generated by the booster and the hydraulic cylinder is transmitted to the three pistons  5 , and the pistons  5  are moved by the hydraulic pressure. As the pistons  5  are moved, the divided bearing  10  is moved by the pistons  5 . The divided bearing  10  pushes the steel wire pulling pieces  27 , so the steel wires  28  connected at their first ends to the steel wire pulling piece  27  are pulled. Finally, the antiskid bar units  20  connected to the second ends of the steel wires  28  are operated, and the bar parts  21  are projected from the circumferential surfaces of the automobile tires.  
         [0046]    The antiskid bar unit  20  is made by inserting the divided guide part  22 , into which the bar part  21  is fitted, into the casing part  23 . The bar part  21  is fitted into the divided guide part  22  with the four crosswise projections  29  of the bar part  21  inserted into the four inclined guide slots  26  of the guide parts  22 . Two springs  24  are positioned on the side surfaces of the divided guide part  22  to return to their original position, and the two steel wires  28  are connected to the rear portion of the divided guide part  22 . The bar part  21  is fitted into the casing part  23  to be vertically moved along the vertical slots formed on the casing part  23 .  
         [0047]    When the antiskid bars are not desired to be utilized, the bar operating switch  7  is manipulated to retract the bar parts  21  into the tires. Accordingly, hydraulic pressure is reduced by the operation of the booster and the hydraulic cylinder, so the pistons  5  of cylinder-piston units mounted on the knuckle  6  are moved rearward to their original positions. The divided bearing  10  having been pushed by the pistons  5  is returned to its original position by the action of a plurality of spring bars  14 . The steel wire pulling pieces  27  having been pulled by the divided bearing  10  are released. As the guide parts  22  are returned to their original positions by the springs  24  positioned in the antiskid bar units  20 , the steel wires  28  connected to the guide parts  22  are pulled to return the steel wire pulling pieces  27  to their original positions. Therefore, the antiskid bar units  20  are restored to their original state, and stand by for the projection of antiskid bars.  
         [0048]    In addition, the hydraulic pistons  5  and the divided bearing  10  are separated from each other so as to prevent friction from occurring between the hydraulic pistons  5  and the divided bearing  10 . The divided bearing  10  is comprised of a left bearing  11 , a right bearing  12  and bearing balls  13 . When the antiskid bars are utilized, the right bearing  12  of the divided bearing  10  is horizontally movably attached to a plurality of guide portions  4  formed on the inside surface of a wheel rim  3 , and can be smoothly and horizontally moved while being rotated by force transmitted from the left bearing  11  in tight contact with the hydraulic piston  5  with the aid of bearing balls  13 .  
       Embodiment 2  
       [0049]    In this embodiment, there is disclosed an apparatus for operating electromagnetic type antiskid bar units  40  embedded in automobile tires by manipulating a bar operating switch  7  in an electromagnetic manner. The automatically operated antiskid apparatus of this embodiment is comprised of a operating signal generating unit, a signal transmitting unit and an antiskid bar and antiskid bar operating unit.  
         [0050]    The signal generating unit consists of the bar operating switch  7  and a plurality of electric wires  30 . The first ends of the electric wires  30  are connected to the bar operating switch  7 , while the second ends of the electric wires  30  are connected to the hubs. Each of the electric wires is comprised of a pair of wire strands.  
         [0051]    The signal transmitting unit consists of a plurality of divided bearings  60 . Each of the divided bearings  60  is comprised of inside and outside bearings  61  and  62  and a plurality of balls  63 . The inside bearing  61  is mounted on a hub and provided with two contacts  64  each surrounded with intercepting material  65 , while the outside bearing  62  is mounted not to be rotated. The first central terminals  31  and  32  of the wire strands of each electric wire  30  pass through the outside bearing  61  and are brought into contact with the contacts  64  formed on the inside bearing  61 , while the second central terminals  33  and  34  of the wire strands of each electric wire  30  pass through the inside bearing  61  and the intercepting material  65  and are connected to the contacts  64  formed on the inside bearing  61 . Accordingly, the second central terminals  33  and  34  passing through the inside bearing  61  are rotated together with the tire  50  and the first central terminals  31  and  32  passing through the outside bearing  62  are not rotated, so the wires  30  are not twisted and an operating signal is continuously transmitted by the contacts  64  formed on the inside bearing  61 .  
         [0052]    There is provided the antiskid bar and antiskid bar operating unit in which the second ends of the electric wires  30  are connected to electromagnets  45  positioned in the casing part  43  of an electromagnetic type antiskid bar unit  40  so that a guide part  42  is moved to project a bar part  41  by moving permanent magnets  45  attached to the side protrusions of the guide part  42 .  
         [0053]    The electromagnetic type antiskid bar unit  40  is comprised of the T-shaped, hollow casing part  43  made of flexible, thin material and provided in its interior with four fixed electromagnets  44  and two vertical guide slots, the guide part  42  provided with a plurality of inclined guide slots and at its both sides with two permanent magnets  45 , and the bar part  41  provided with a plurality of projections and situated between two members of the guide part  42  with the projections inserted into the inclined guide slots of the guide part  42 . The bar part  41  can be vertically moved along vertical guide slots formed in the casing part  42 .  
         [0054]    When bar parts  41  having been projected from the tread portions of the tires are not desired to be utilized, the bar operating switch  7  is manipulated to retract the bar parts  41  into the tread portions of the tires. Accordingly, an operating signal for retracting the antiskid bars is transmitted to the antiskid bar and antiskid bar operating units through the wires  30  and the signal transmitting unit. The magnetic poles of the four electromagnets  44  formed on the antiskid bar units  40  are changed, so the guide parts  42  and the bar part  41  are returned to their original states.  
         [0055]    Therefore, the electromagnetic antiskid bar units  40  are restored to their original state, and stand by for the projection of bar parts.  
       Embodiment 3  
       [0056]    In this embodiment, there is disclosed an apparatus for operating antiskid block units  70  embedded in automobile tires by manipulating a block operating switch  7  using coils. The automatically operated antiskid apparatus of this embodiment is comprised of a operating signal generating unit, a signal transmitting unit and an antiskid block and antiskid block operating unit. The signal generating unit consists of the block operating switch  7  and electric wires  30 . Each of the electric wires is comprised of a pair of wire strands.  
         [0057]    The signal transmitting unit consists of a plurality of divided bearings  60 . Each of the divided bearings  60  is comprised of inside and outside bearings  61  and  62  and a plurality of balls  63 . The inside bearing  61  is mounted on a hub and provided with two contacts  64  each surrounded with intercepting material  65 , while the outside bearing  62  is mounted not to be rotated. The first central terminals  31  and  32  of the wire strands of each electric wire pass through the outside bearing  61  and are brought into contact with the contacts  64  formed on the inside bearing  61 , while the second central terminals  33  and  34  of the wire strands of each electric wire pass through the inside bearing  61  and the intercepting material  65  and are connected to the contacts  64  formed on the inside bearing  61 . Accordingly, the second terminals  33  and  34  passing through the inside bearing  61  are rotated together with the tire  50  and the first terminals  31  and  32  passing through the outside bearing  62  are not rotated, so the wires  30  are not twisted and an operating signal is continuously transmitted by the contacts  64  formed on the inside bearing  61 .  
         [0058]    There is provided the antiskid block and antiskid block operating unit in which the second ends of the electric wires  30  are connected to coils  74  positioned in the casing parts  73  of electromagnetic type circular antiskid block units  70  embedded in the tread portions  51  of tires so that the block parts  71  of the electromagnetic type circular antiskid block units  70  are rotated by utilizing the principle of an electromagnet.  
         [0059]    Each of the electromagnetic circular antiskid block units  70  is comprised of the cylindrical casing part  73  which is made of rubber and in which a coil  74  is situated, the cylindrical guide part  72  positioned inside of the casing part  73  and provided with a plurality of inclined guide slots  76 , and the block part  71  positioned inside of the guide part  72  and provided at its outside surface with a plurality of projections  75  inserted into the guide slots  76 .  
         [0060]    When the block parts  71  having been projected from the tread portions of the automobile tires are not desired to be utilized, the block operating switch  7  is manipulated to retract the block parts  71  into the tread portions of the automobile tires. Accordingly, an operating signal for projecting the block parts  71  is transmitted to the antiskid block and antiskid block operating unit through the wire  30  and the signal transmitting unit. The block parts  71  are reversely rotated by the coils  74  contained in the casing parts  73 . Therefore, the electromagnetic type circular antiskid block units  20  are restored to their original state, and stand by for the projection of the block parts.  
         [0061]    A plurality of bolts  25  attached to the bar parts  21  and  41  and the block parts  71  are mounted to be easily replaced by new ones.  
         [0062]    As described above, the present invention provides an automatically operated antiskid apparatus for automobile tires, which allows a driver to project the antiskid bars from the tread portions of the automobile tires and retract the antiskid bars into the tires by manipulating a bar operating switch without getting out of the automobile, and which allows worn antiskid bars to be easily repaired by replacing bolts, thereby improving the convenience of a driver and contributing to safe driving.  
         [0063]    Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.