Vehicle step apparatus and extending and retracting device therefor

A vehicle step includes a step member and first and second extending and retracting devices connected to the step member for moving it between extended and retracted positions. Each of the extending and retracting devices includes a mounting bracket adapted to be fixed to a vehicle body, a step bracket connected to the step member, first and second arms each defining a lower end rotatably connected to the step bracket and an upper end, and a third arm defining an upper end rotatably connected to the mounting bracket and a lower end rotatably connected to the upper end of the first or second arm. The upper end of the other of the first or second arm is rotatably connected to the mounting bracket. The vehicle step includes also driving devices that drive respectively the extending and retracting devices to move the step member between the extended and retracted positions.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates, generally, to a vehicle body and, more particularly, to a step of the vehicle body and an extending and retracting device for the step.

2. Description of the Related Art

A step under a door of a vehicle is used for a passenger to get on or off the vehicle. In terms of ergonomics, the vehicle step is generally mounted at a level of 15 cm with respect to the ground so that it is convenient for the passenger to get on or off it, but this level does not provide sufficient ground clearance during operation of many vehicles. The level of the vehicle step should be higher than ground clearance of the vehicle. Therefore, it is difficult to meet ground-clearance and convenience requirements simultaneously with a conventional vehicle step.

U.S. Pat. No. 6,830,257 discloses a retractable vehicle step employing a four-link mechanism. When a door of a vehicle is opened, the vehicle step is automatically extended out downwardly from the chassis of the vehicle near the board of the body of the vehicle so that a passenger can step on the extended vehicle step. When the vehicle door is closed, the vehicle step is automatically retracted upwardly to its original position, thus not affecting disadvantageously ground clearance of the vehicle.

The retractable vehicle step disclosed in U.S. Pat. No. 6,830,257 employs one motor to drive a pair of four-link mechanisms used to deploy and retract a step member. Since the pair of four-link mechanisms is driven by one motor, a driving force applied to the retractable vehicle step is not balanced, and rotations of two four-link mechanisms of the retractable vehicle step are not synchronous so that operation of the retractable vehicle step is not reliable. If a conventional four-link retractable vehicle step employs two motors to drive the two four-link mechanisms simultaneously, rotations of the two motors and/or four-link mechanisms may not be synchronous so that the four-link mechanisms may interfere with each other. The retractable vehicle step may be destroyed due to the interference and fail to operate. Thus, there is a need in the related art for a retractable vehicle step that is stable and not subject to these deficiencies and operation of which is reliable.

SUMMARY OF THE INVENTION

The present invention overcomes the disadvantages in the related art in a vehicle step apparatus. The vehicle step apparatus includes a step member and first and second extending and retracting devices connected to the step member for moving the step member between an extended position and a retracted position. Each of the first and second extending and retracting devices includes a mounting bracket adapted to be fixed to a body of a vehicle, a step bracket connected to the step member, a first arm defining a lower end portion thereof rotatably connected to the step bracket and an upper end portion thereof, a second arm defining a lower end portion thereof rotatably connected to the step bracket and an upper end portion thereof, and a third arm defining an upper end portion thereof rotatably connected to the mounting bracket and a lower end portion thereof rotatably connected to the upper end portion of the first or second arm. The upper end portion of the other of the first or second arm is rotatably connected to the mounting bracket. The vehicle step apparatus includes also first and second driving devices that drive respectively the first and second extending and retracting devices to move the step member between the extended and retracted positions.

One advantage of the vehicle step apparatus of the present invention is that it employs a five-link mechanism, is reliable and stable with a long operational life, and eliminates interference occurring between the two extending and retracting devices.

Another advantage of the vehicle step apparatus of the present invention is that its freedom of movement is increased and it employs the two driving devices to drive respectively the two extending and retracting devices with increased driving force.

Another advantage of the vehicle step apparatus of the present invention is that even if rotations of the two driving devices and/or extending and retracting devices are not synchronous, asynchronization can be compensated by relative rotation between the third arm and first or second arm.

Other objects, features, and advantages of the present invention will be readily appreciated as the same becomes better understood while reading the subsequent description taken in conjunction with the accompanying drawings.

DETAILED DESCRIPTION OF THE INVENTION

An extending and retracting device for a vehicle step apparatus of the present invention is shown inFIGS. 1 through 12, and a vehicle step apparatus using the extending and retracting device is shown inFIGS. 13 through 18. In the figures, like numerals are used to designate like structure throughout various embodiments of each of the device and apparatus disclosed herein. Embodiments of the extending and retracting device and the vehicle step apparatus using the device of to the present invention are described hereinafter with reference to the figures. The embodiments are exemplary only and cannot be construed to limit the present invention. In the description of the present invention that follows, it should be noted that the terminologies “first,” “second,” “third,” “upper,” and “lower” are used only to describe the present invention conveniently and cannot be construed to limit the present invention. Although the extending and retracting device is designed to be used in connection with the vehicle step apparatus described below, those having ordinary skill in the related art should appreciate that the extending and retracting device can be used in connection with any suitable vehicle step.

With reference toFIGS. 1-3, a first embodiment of the extending and retracting device for a vehicle step apparatus of the present invention will now be described. The first embodiment generally includes a mounting bracket1adapted to be fixed to a body of a vehicle (not shown). A step bracket8is adapted to be connected to a step member9(as shown inFIG. 13) of the vehicle step apparatus. A first arm4defines a lower end portion rotatably connected to the step bracket8and an upper end portion. A second arm5defines a lower end portion rotatably connected to the step bracket8and an upper end portion. A third arm6defines an upper end portion rotatably connected to the mounting bracket1and a lower end portion rotatably connected to the upper end portion of the first arm4or second arm5. The upper end portion of the other of the first arm4or second arm5is rotatably connected to the mounting bracket1. The mounting bracket1can be mounted to the body of the vehicle so as to mount the extending and retracting device onto the vehicle.

More specifically and as shown inFIG. 1, the lower end portion of the first arm4is rotatably connected to the step bracket8. In particular, the lower end portion of the first arm4is formed with through-hole413, and each side wall of the step bracket8is formed with through-hole811. Pin13is received in through-holes413,811so that the first arm4is pivotably connected via pin13to the step bracket8.

The upper end portion of the first arm4is rotatably connected to the mounting bracket1. As shown inFIG. 1, groove410is formed in the upper end portion of the first arm4, and the mounting bracket1is inserted into groove410such that the mounting bracket1and first arm4can rotate with respect to each other. In particular, each side wall of the upper end portion of the first arm4defined by groove410is formed with through-hole412, and the mounting bracket1is formed with through-hole110. Pin10is received in through-holes412,110so that the upper end portion of the first arm4is pivotably connected via pin10to the mounting bracket1.

As shown inFIG. 1and similar to the first arm4, the lower end portion of the second arm5is rotatably connected to the step bracket8. In particular, the lower end portion of the second arm5is formed with through-hole512, and each side wall of the step bracket1is formed with through-hole812. Pin14is received in through-holes512,812so that the second arm5is pivotably connected via pin14to the step bracket8.

The step member9can be mounted on the step bracket8. In particular, the step bracket8is formed with an extension portion814at the lower end so that the step member9can be mounted on the extension portion814.

The lower end portion of the third arm6is rotatably connected to the upper end portion of the second arm5. As shown inFIG. 1, groove611is formed in the third arm6, and the upper end portion of the second arm5is rotatably inserted into groove611. In particular, each side wall of the lower end portion of the third arm6defined by groove611is formed with through-hole613, and a protrusion portion510(the width of which is decreased with respect to that of the remainder of the second arm5) is formed on the upper end portion of the second arm5and with through-hole511. Pin12is received in through-holes613,511so that the lower end portion of the third arm6is pivotably connected via pin12to the upper end portion of the second arm5.

The upper end portion of the third arm6is rotatably connected to the mounting bracket1. As shown inFIG. 1, groove610is formed in the upper end portion of the third arm6, and the mounting bracket1is inserted into groove610so that the third arm6can be rotated with respect to the mounting bracket1. In particular, each side wall of the upper end portion of the third arm defined by groove610is formed with through-hole612, and the mounting bracket1is formed with through-hole111. Pin11is received in through-holes612,111so that the upper end portion of the third arm6is pivotably connected via pin11to the mounting bracket1.

InFIG. 1, a driving device for driving the extending and retracting device is also shown. In one embodiment, the driving device may include a reversible motor3and a speed reducer2. In particular, an output shaft of the speed reducer2is connected to pin10so as to drive pin10and cause the first arm4to rotate so that the driving device drives the first arm4to move the extending and retracting device between an extended state and a retracted state. In this way, the step member9is moved between the extended and retracted positions.

FIG. 2shows the extending and retracting device disposed in the extended state in which the step member9is connected to the step bracket8in an extended position (as shown inFIG. 14).FIG. 3shows the extending and retracting device disposed in the retracted state in which the step member9is connected to the step bracket8in a retraced position (as shown inFIG. 15).

In operation of the first embodiment of the extending and retracting device and as shown inFIGS. 2 and 3, when it is required to move the extending and retracting device from the extended state (as shown inFIG. 2) to the retracted state (as shown inFIG. 3), the reversible motor3rotates the first arm4in counter-clockwise direction (as viewed inFIG. 2) with respect to the mounting bracket1via the speed reducer2, thus driving the second arm5and third arm6to rotate with respect to the mounting bracket1so that the step bracket8moves upwardly and rearwardly with respect to the mounting bracket1. In this way, the extending and retracting device moves to its retracted state (as shown inFIG. 3). Through reversed rotation of the motor3, the extending and retracting device can move from the retracted state (as shown inFIG. 3) to the extended state (as shown inFIG. 2).

It should be appreciated by those having ordinary skill in the related art that in the first embodiment of the extending and retracting device, each of the mounting bracket1, speed reducer2, reversible motor3, first arm4, second arm5, third arm6, step bracket8, pins10,11,12,13,14, protrusion portion510, and extension portion814can have any suitable shape, size, and structure. It should also be appreciated that each of the through-holes110,111,412,413,511,512,612,613,811,812and grooves410,610,611can have any suitable shape and size. It should also be appreciated also that each of the mounting bracket1, speed reducer2, reversible motor3, first arm4, second arm5, third arm6, step bracket8, step member9, pins10,11,12,13,14, protrusion portion510, extension portion814, through-holes110,111,412,413,511,512,612,613,811,812, and grooves410,610,611can have any suitable structural relationship with each other and the step member9and body of the vehicle.

With reference toFIG. 4, a second embodiment of the extending and retracting device for a vehicle step apparatus of the present invention will now be described. Those having ordinary skill in the related art should appreciate that structure and operation of the second embodiment is similar to those of the first embodiment. Accordingly, the description that follows focuses upon differences between the first and second embodiments.

In the second embodiment, groove411is formed in the lower end portion of the first arm4, and groove513formed in the lower end portion of the second arm5. The step bracket8is inserted into grooves411,513. In particular, the step bracket8is pivotably connected to the respective lower end portions of the first arm4and second arm5via corresponding pins13,14. Otherwise, the second embodiment illustrated inFIG. 4functions the same as the first embodiment illustrated inFIGS. 1-3.

With reference toFIG. 5, a third embodiment of the extending and retracting device for a vehicle step apparatus of the present invention will now be described. Those having ordinary skill in the related art should appreciate that structure and operation of the third embodiment is similar to those of the first or second embodiment. Accordingly, the description that follows focuses upon differences between the first or second and third embodiments.

In the third embodiment, the respective lower end portions of the first arm4and second arm5are juxtaposed with respect to each other and connected to the step bracket8. In other words, the respective lower end portions of the first arm4and second arm5are connected to the step bracket8side by side with respect to each other. A notch414is formed in the lower end portion of the first arm4such that the lower end portion of the first arm4is formed as a width-reduced protrusion portion, a notch514is formed in the lower end portion of the second arm5such that the lower end portion of the second arm5is formed as a width-reduced protrusion portion, and a notch813is formed in an upper portion of the step bracket8such that the upper portion of the step bracket8is formed as a width-reduced protrusion portion. In this way, the respective lower end portions of the first arm4and second arm5are connected via corresponding pins13,14to the step bracket8side by side with respect to each other.

However, those having ordinary skill in the related art should appreciate that the respective lower end portions of the first arm4and second arm5and the upper portion of the step bracket8can be formed with no notches. Alternatively, the respective lower end portions of the first arm4and second arm5may be juxtaposed to the upper portion of the step bracket8directly. The term “juxtaposed” as used herein means that the step bracket8is not inserted into the first arm4and second arm5(as compared to the step bracket8of the second embodiment). Namely, the respective lower end portions of the first arm4and second arm5are connected to the step bracket8side by side with respect to each other.

With reference toFIG. 6, a fourth embodiment of the extending and retracting device for a vehicle step apparatus of the present invention will now be described. Those having ordinary skill in the related art should appreciate that structure and operation of the fourth embodiment is similar to those of the first or second embodiment. Accordingly, the description that follows focuses upon differences between the first or second and fourth embodiments.

In the fourth embodiment, the mounting bracket1is formed with recess112, and the upper end portion of the third arm6is rotatably inserted into recess112. In particular, the upper end portion of the third arm6is pivotably connected to the mounting bracket1in recess112via pin11. The upper end portion of the first arm4is rotatably inserted into recess112. In particular, the upper end portion of the first arm4is pivotably connected to the mounting bracket1in recess112via pin10. Not by way of limitation, the width of the respective upper end portions of the third arm6and first arm4is reduced such that they adapt to recess112.

With reference toFIG. 7, a fifth embodiment of the extending and retracting device for a vehicle step apparatus of the present invention will now be described. Those having ordinary skill in the related art should appreciate that structure and operation of the fifth embodiment is similar to those of the fourth embodiment. Accordingly, the description that follows focuses upon differences between the fourth and fifth embodiments.

In the fifth embodiment, the respective upper end portions of the first arm4and third arm6are juxtaposed with respect to each other and connected to the mounting bracket1. In other words, the respective upper end portions of the first arm4and third arm6are connected to the mounting bracket1side by side with respect to each other. A notch415is formed in the upper end portion of the first arm4such that the upper end portion of the first arm4is formed as a width-reduced protrusion portion, a notch614is formed in the upper end portion of the third arm6such that the upper end portion of the third arm6is formed as a width-reduced protrusion portion, and a notch113is formed in a lower portion of the mounting bracket1such that the lower portion of the mounting bracket1is formed as a width-reduced protrusion portion. In this way, the respective upper end portions of the first arm4and third arm6are pivotably connected via corresponding pins10,11to the mounting bracket1side by side with respect to each other.

However, those having ordinary skill in the related art should appreciate that the respective upper end portions of the first arm4and third arm6and the lower portion of the mounting bracket1can be formed with no notches. Alternatively, the respective upper end portions of the first arm4and third arm6may be juxtaposed to the lower portion of the mounting bracket1directly. The term “juxtaposed” as used herein means that neither the first arm4nor third arm6is inserted into the mounting bracket1(as compared to the first arm4and third arm6of the fourth embodiment) and the mounting bracket1is not inserted into the first arm4and third arm6(as compared to the mounting bracket1of the first through third embodiments). Namely, the respective upper end portions of the first arm4and third arm6are connected to the mounting bracket1side by side with respect to each other.

With reference toFIGS. 8 through 10, a sixth embodiment of the extending and retracting device for a vehicle step apparatus of the present invention will now be described. Those having ordinary skill in the related art should appreciate that structure and operation of the sixth embodiment is similar to those of the first embodiment. Accordingly, the description that follows focuses upon differences between the first and sixth embodiments.

In the sixth embodiment, the lower end portion of the third arm6is rotatably connected to the upper end portion of the first arm4, the upper end portion of the third arm6is rotatably connected to the mounting bracket1, and the lower end portion of the first arm4is rotatably connected to the step bracket8. The upper end portion of the second arm5is rotatably connected directly to the mounting bracket1, and the lower end portion of the second arm5is rotatably connected to the step bracket8.

More specifically and as shown inFIG. 8, the lower end portion of the third arm6is formed as a protrusion portion615, groove410is formed in the upper end portion of the first arm4, and the protrusion portion615is inserted into groove410and pivotably connected via pin10to the first arm4. The respective lower end portions of the first arm4and second arm5are pivotably connected to the step bracket8via corresponding pins13,14.

FIG. 9shows the extending and retracting device of the sixth embodiment disposed in the extended state, andFIG. 10shows the extending and retracting device of the sixth embodiment disposed in the retracted state. In the sixth embodiment, the driving device drives the extending and retracting device by driving the third arm6.

With reference toFIG. 11, a seventh embodiment of the extending and retracting device for a vehicle step apparatus of the present invention will now be described. Those having ordinary skill in the related art should appreciate that structure and operation of the seventh embodiment is similar to those of the sixth embodiment. Accordingly, the description that follows focuses upon differences between the sixth and seventh embodiments.

In the seventh embodiment, the lower end portion of the first arm4is formed with groove411, and the lower end portion of the second arm5is formed with groove513. The step bracket8is inserted into grooves411,513and pivotably connected to the first arm4and second arm5via corresponding pins13,14.

With reference toFIG. 12, an eighth embodiment of the extending and retracting device for a vehicle step apparatus of the present invention will now be described. Those having ordinary skill in the related art should appreciate that structure and operation of the eighth embodiment is similar to those of the sixth embodiment. Accordingly, the description that follows focuses upon differences between the sixth and eighth embodiments.

In the eighth embodiment, the respective lower end portions of the first arm4and second arm5are juxtaposed to the step bracket8. In the sixth through eight embodiments, the upper end portion of the third arm6is formed with groove610, the upper end portion of the second arm5is formed with groove515, and the mounting bracket1is inserted into grooves610,515. The mounting bracket1can be formed with recess112(as shown inFIG. 6). In this case, the respective upper end portions of the third arm6and second arm5are inserted into the recess112. Those having ordinary skill in the related art should appreciate that the respective upper end portions of the third arm6and second arm5can be juxtaposed to the mounting bracket1.

It should be appreciated by those having ordinary skill in the related art that in each of the second through eighth embodiments of the extending and retracting device, each of the pins10,11,13,14and protrusion portion615can have any suitable shape, size, and structure. It should also be appreciated that each of the recess112, grooves410,411,513,515,610, and notches113,414,415,514,614,813can have any suitable shape and size. It should also be appreciated that each of the pins10,11,13,14, protrusion portion615, recess112, grooves410,411,513,515,610, and notches113,414,415,514,614,813can have any suitable structural relationship with each other.

With reference toFIGS. 13-15, a first embodiment of the vehicle step apparatus of the present invention will now be described. In general, this embodiment of the vehicle step apparatus includes a step member9and first and second extending and retracting devices connected to the step member9for moving the step member9between an extended position (as shown inFIG. 14) and a retracted position (as shown inFIG. 15). Each of the extending and retracting devices includes a mounting bracket1adapted to be fixed to a body of a vehicle. A step bracket8is connected to the step member9. A first arm4defines a lower end portion and an upper end portion. The lower end portion is rotatably connected to the step bracket8. A second arm5defines a lower end portion and an upper end portion. The lower end portion is rotatably connected to the step bracket8. A third arm6defines an upper end portion rotatably connected to the mounting bracket1and a lower end portion rotatably connected to the upper end portion of the first arm4or second arm5. The upper end portion of the other of the first arm4or second arm5is rotatably connected to the mounting bracket1. The vehicle step apparatus also includes first and second driving devices that drive respectively the extending and retracting devices to move the step member9between the extended and retracted positions.

More specifically, the mounting bracket1can be mounted to the body of the vehicle so as to mount the extending and retracting device to the vehicle. The step member9is mounted onto the step brackets8of the respective extending and retracting devices. The lower end portion of the first arm4is rotatably connected to the step bracket8. In particular, the lower end portion of the first arm4is pivotably connected to the step bracket8via pin13. The upper end portion of the first arm4is rotatably connected to the mounting bracket1. In particular, the upper end portion of the first arm4is pivotably connected to the mounting bracket1via pin10. The lower end portion of the second arm5is rotatably connected to the step bracket8. In particular, the lower end portion of the second arm5is pivotably connected to the step bracket8via pin14. The upper end portion of the third arm6is rotatably connected to the mounting bracket1. In particular, the upper end portion of the third arm6is pivotably connected to the mounting bracket1via pin11. The lower end portion of the third arm6is rotatably connected to the upper end portion of the second arm5. In particular, the lower end portion of the third arm6is pivotably connected to the upper end portion of the second arm5via pin12.

In one embodiment, each of the driving devices includes the reversible motor3and speed reducer2. In particular, the reversible motors3drive respectively the first arms4via the corresponding speed reducers2so as to move the extending and retracting devices between the extended and retracted states, thus moving the step member9between the extended and retracted positions. Each of the driving devices is not limited to drive the first arm4and can drive the second arm5or third arm6. As shown inFIG. 13and not by way of limitation, the driving devices drive respectively the first arms4of the corresponding extending and retracting devices.

In operation of the first embodiment of the vehicle step apparatus and as shown inFIG. 14, the vehicle step apparatus is in the extended state in which the step member is in the extended position. The reversible motors3drive respectively the first arms4of the extending and retracting devices via the corresponding speed reducers2to rotate the first arms4in counterclockwise direction relative to the mounting brackets1, thereby driving the second arms5and third arms6to rotate in counterclockwise direction relative to the mounting brackets1so that the step brackets8move upwardly and rearwardly relative to the mounting brackets1. In this way, the extending and retracting devices move from the extended state (as shown inFIG. 14) to the retracted state (as shown inFIG. 15) while the step member9moves from the extended position (as shown inFIG. 14) to the retracted position (as shown inFIG. 15). When the step member9is moved from the retracted to extended position so that a passenger may use the step member9, the reversible motors3drive respectively the first arms4via the corresponding speed reducers2to rotate the first arms4in the clockwise direction relative to the mounting brackets1so that the extending and retracting devices move from the retracted state (as shown inFIG. 15) to the extended state (as shown inFIG. 14), and the step member9moves from the retracted position (as shown inFIG. 15) to the extended position (as shown inFIG. 14) for a passenger stepping on the step member9.

If rotation of the reversible motor3of the first driving device is not synchronous with that of the second driving device and/or rotation of the first extending and retracting device is not synchronous with that of the second extending and retracting device, such asynchronization can be compensated for by relative rotation between the second arms5and third arms6, thus eliminating interference of the first extending and retracting device with the second extending and retracting device. In other words, the vehicle step apparatus employs a five-link mechanism, which increases freedom of movement of each extending and retracting device, and eliminates interference so that operation life and reliability of the vehicle step apparatus and extending and retracting device therefor are increased. Because two driving devices are used to drive respectively two extending and retracting devices, resulting driving forces are increased, and operation of the vehicle step apparatus is very stable.

With reference toFIGS. 16 through 18, a second embodiment of the vehicle step apparatus of the present invention will now be described. Those having ordinary skill in the related art should appreciate that structure and operation of the second embodiment is similar to those of the first embodiment. Accordingly, the description that follows focuses upon differences between the first and second embodiments.

With respect to each of the extending and retracting devices, the lower end portion of the third arm6is rotatably connected to the upper end portion of the first arm4. The upper end portion of the third arm6is rotatably connected to the mounting bracket1, and the lower end portion of the first arm4is rotatably connected to the step bracket8. The upper end potion of the second arm5is rotatably connected directly to the mounting bracket1, and the lower end portion of the second arm5is rotatably connected to the step bracket8. The reversible motor3drives the third arm6via the speed reducer2. Asynchronization between the extending and retracting devices and/or reversible motors3can be compensated for by relative rotation between the third arm6and first arm4, thus eliminating interference of the first extending and retracting device with the second extending and retracting device.

FIG. 17shows the second embodiment disposed in an extended state with the step member9being in an extended position, andFIG. 18shows the second embodiment disposed in a retracted state with the step member being in a retracted position.

As shown inFIG. 13, the vehicle step apparatus of the first embodiment employs two extending and retracting devices of the first embodiment of the present invention. That is, the extending and retracting devices are identical with each other. As shown inFIG. 16, the vehicle step apparatus of the second embodiment employs two extending and retracting devices of the sixth embodiment of the present invention. That is, the extending and retracting devices are identical with each other. However, those having ordinary skill in the related art should appreciate that the extending and retracting devices can be different from each other. For example, the first extending and retracting device can be any of the first through eighth embodiments of the extending and retracting device of the present invention, and the second extending and retracting device can be any of such embodiments as well.

It should be appreciated by those having ordinary skill in the related art that in each of the first and second embodiments of the vehicle step apparatus, each of the mounting brackets1, speed reducers2, reversible motors3, first arms4, second arms5, third arms6, step brackets8, step member9, pins10,11,12,13,14, and driving devices can have any suitable shape, size, and structure and structural relationship with each other and the body of the vehicle.

The vehicle step apparatus of the present invention employs a five-link mechanism, is reliable and stable with a long operational life, and eliminates interference occurring between the two extending and retracting devices. In addition, freedom of movement of the vehicle step apparatus is increased, when compared to conventional four-link mechanisms, and the vehicle step apparatus employs the two driving devices to drive respectively the two extending and retracting devices with increased driving force. Moreover, even if rotations of the two driving devices and/or extending and retracting devices are not synchronous, asynchronization can be compensated by relative rotation between the third arm and first or second arm.