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(11) | EP 1 972 232 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Driving device for a footrest pedestal |
| (57) A driving device for a footrest pedestal is mounted between a frame (3) and a footrest
(2) on the frame (3) and has a driver body (11) with two ends respectively equipped
with a retractable driving shaft (111) and the pivotal block (112), a motor (113)
mounted beside the driver body (11), and an auxiliary pivotal base mounted on the
frame (3) to combine with the pivotal block (112). The auxiliary pivotal base has
a movable connector (12) engaged with the pivotal block (112), an immovable connector
(14) mounted on the frame (3) and an extension rod (13) pivotally connected between
the movable and immovable connectors (12, 14) so that the extension rod (13) is liftable
to adjust the distance of a lower end of the driver body (11) and an end of the driving
shaft (111) to keep the driving shaft (111) retracting thus to avoid motor idle running.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
[0001] The present invention relates to a driving device for a footrest pedestal, and more particularly to a driving device that is adjustable in structure orientation to avoid idle running of a motor or inadvertent clamping to users when the footrest pedestal is folded.
2. Description of Related Art
[0002] A conventional driving device 9 for a footrest pedestal as shown in Figs. 1 and 2 comprises a driver body 91 and two pivotal bases 92, 93 combining the driver body 91 to a frame 7 and a footrest 8. Two ends of the driver body 91 respectively have a retractable driving shaft 911 and a pivotal block 912 to pivotally engage the two pivotal bases 92, 93. Wherein, the two pivotal bases 92, 93 are respectively mounted on a bottom rail 71 of the frame 7 and an inner section of the footrest 8. A motor 913 is installed beside the driver body 91 to extend or retract the driver body 91 so that the footrest 8 is liftable.
[0003] When the motor 913 on the driver body 91 makes the driving shaft 911 to retract to lower the footrest 8 but with an obstacle 6 in its moving path as shown in Fig. 3, the footrest 8 can not be lowered and stopped to move. Meanwhile, the motor 913 of the driver body 91 keeps running idly but the driving shaft 911 can not get closer anymore because distance of a lower end of the driver body 91 and an end of the driving shaft 911 is unchangeable. When the motor 913 of the driver body 91 can not move the driving shaft 911 but runs idly, the motor 913 will be malfunctioned soon in great possibility. Moreover, a user might get injury when the obstacle 6 is the user's limb when the footrest is pivotally lowered.
SUMMARY OF THE INVENTION
[0004] One main objective of the present invention is to provide a driving device for a footrest pedestal that is adjustable in structure to keep operation of the footrest smooth when obstacle exists.
[0005] To achieve the foregoing objective, the driving device for a footrest pedestal comprises:
a driver body with two ends respectively equipped with a retractable driving shaft and a pivotal block;
a motor attached to the driver body to drive the driving shaft that is adapted to pivotally attach to a footrest;
wherein, improvements of the driving device comprise:a movable connector pivotally engaged the pivotal block of the driver body;
an extension rod pivotally connected to the movable connector at one end; and
an immovable connector adapted to mount on a frame and pivotally received another end of the extension rod.
[0006] According to a particular embodiment of the present invention, the immovable connector further has a limiting bar mounted thereon.
[0007] By having the movable connector and the extension rod, the driving shaft can be lifted up with the driver body and then retracted into the driver body even when the footrest is obstructed.
[0008] Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009]
Fig. 1 is a perspective view of a conventional driving device for a footrest pedestal in accordance with the prior art;
Fig. 2 is a cross-sectional side view of the conventional driving device, wherein a footrest is raised;
Fig. 3 is a cross-sectional side view of the conventional driving device, wherein a footrest is lowered;
Fig. 4 is a perspective view of a driving device for a footrest pedestal in accordance with the present invention;
Fig. 5 is a cross-sectional side view of the driving device in Fig. 4;
Fig. 6 is an operational perspective view of the driving device, wherein a footrest is raised;
Fig. 7 is an operational cross-sectional side view of the driving device in Fig. 6;
Fig. 8 is an operational perspective view of the driving device, wherein a footrest is completely raised in horizontal;
Fig. 9 is an operational cross-sectional side view of the driving device in Fig. 8;
Fig. 10 is an operational perspective view of the driving device, wherein a footrest is blocked by an obstacle; and
Fig. 11 is an operational cross-sectional side view of the driving device in Fig. 10.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0010] A driving device for a footrest pedestal in accordance with the present invention is mounted between a frame and a footrest on the frame and comprises a driver body with two ends respectively equipped with a retractable driving shaft and the pivotal block, a motor mounted beside the driver body, and an auxiliary pivotal base mounted on the frame to combine with the pivotal block. Particularly, the auxiliary pivotal base comprises a movable connector engaged with the pivotal block, an immovable connector mounted on the frame and an extension rod pivotally combined between the movable and immovable connectors so that the extension rod is liftable to adjust the distance of a lower end of the driver body and an end of the driving shaft to keep the retraction of the driving shaft working thus to avoid a motor from idle running when the footrest is blocked or avoid inadvertent clamping to users.
[0011] With reference to Figs. 4 and 5, a preferred embodiment of the driving device is adapted to mount on a frame 3 with a footrest 2 pivotally attached to a top front of the frame 3. Wherein, the frame 3 is substantially a parallelepiped and has a bottom rail 31 in vertical orientation to the footrest 2. The driving device comprises a driver body 11, a movable connector 12, an extension rod 13 and an immovable connector 14, wherein the movable connector 12, the immovable connector 14 and the extension rod 13 are particularly integrated and named as the auxiliary pivotal base to make the driver body 11 liftable.
[0012] Two ends of the driver body 11 are equipped with a retractable driving shaft 111 and a pivotal block 112 respectively. A motor 113 is vertically attached to a side of the driver body 11. The driving shaft 111 and the pivotal block 112 are respectively attached to a pivotal base 21 at a middle on an inner edge of the footrest 2 and to a upper section of the movable connector 12.
[0013] The movable connector 12 has the upper section and a lower section respectively connecting to the pivotal block 112 on the driver body 11 and one end of the extension rod 13.
[0014] The extension rod 13 connects between the movable connector 12 and the immovable connector 14 and has another end pivotally attached to the immovable connector 14.
[0015] The immovable connector 14 is U-shaped pivotally to receive the extension rod 13, has a bottom adapted to attach to the bottom rail 31 of the frame 3 and further has a limiting bar 141 mounted thereon at an outer side crossing over the extension rod 13.
[0016] When the motor 113 on the driver body 11 drive the driving shaft 111 to extend outward as shown in Figs. 6 and 7, the footrest 2 is pivotally moved upward to rise. When the driving shaft 111 of the driver body 11 extends to an extreme point, the footrest 2 reaches a horizontal position parallel to a top face of the frame 3 as shown in Figs. 8 and 9. Therefore, a user enables to rest the shanks on the footrest 2 high.
[0017] When the motor 113 on the driver body 11 drives the driving shaft to retract as shown in Figs. 4 and 5, the footrest 2 is pivotally lowered. When the driving shaft 111 of the driver body 11 retracts to an extreme point, the footrest 2 reaches a horizontal position parallel to a front face of the frame 3 as shown in Figs. 8 and 9. Therefore, the footrest 2 is settled to attach close the frame 3 when the footrest in not in use.
[0018] When the motor 113 on the driver body 11 drives the driving shaft 111 retracts but with an obstacle 4 as shown in Figs. 1 and 11, the footrest 2 is stopped to lower. Meanwhile the motor 113 on the driver body 11 keep running to retract the driving shaft 111. Then, the driver body 11 moves close to the footrest 2 by the retraction of the driving shaft 111. The driver body 11 and the movable connector 12 take a pivotal end of the extension rod 13 as a pivot center to swing upward until the extension rod 13 is stopped by the limiting bar 141 on the immovable connector 14. Thereby, the upward movement of the driver body 11 and the movable connector 12 is limited to stop.
[0019] According to above description, the driving device for a footrest pedestal has the following advantages:
- 1. By pivotally connecting the driver body 11 to the extension rod 13 and pivotally connecting the extension rod 13 to the movable connector 12, a distance between a lower end of the driver body 11 and an end of the driving shaft 111 is shorten when the footrest 2 is blocked on the path of pulling close to the frame 3. In other words, the driving shaft 111 is still driven by the motor 113 to retract into the driver body when the footrest 2 is obstructed in the retraction operation. Therefore, the idle running of the motor in the conventional driving device caused by the obstruction is thus eliminated.
- 2. Moreover, user's limbs are not easily clamped by the footrest 2 because the driving shaft 111 has an additional structure deformation provided by the movable connector 12 and the extension rod 13. Therefore, the footrest 2 is safe in operation especially when retracting.
- 3. With the limiting bar 141 on the immovable connector 14, the extension rod 13 is blocked to provide a limiting and stopping function to the driver body 11 and the movable connector 12 during pivotally moving upward.
- 4. Structure of the driving device in the present invention is achieved by simply adding the movable connector 12 and the extension rod 13 to significantly prevent damages of the driver body 11 so that manufacturing process of the driving device is easy in comparison with a conventional one mentioned in the background.
a driver body (11) with two ends respectively equipped with a retractable driving shaft (111) and a pivotal block (112);
a motor (113) attached to the driver body (11) to drive the driving shaft (111) that is adapted to pivotally attach to the footrest (2);
wherein, improvements of the driving device comprise:a movable connector (12) pivotally engaged the pivotal block (112) of the driver body (11);
an extension rod (13) pivotally connected to the movable connector (12) at one end; and
an immovable connector (14) adapted to mount on the frame (3) and pivotally received another end of the extension rod (13).