Footrest of chair

Abstract

To provide a footrest of a chair.SOLUTION: A flexible footrest of a chair comprises: a basis 1, a seat part 2, a backrest 3, an operation unit 4 and a footrest 5. The seat part 2 is provided above the basis 1, has a first pivotal fitting part 23, a first shaft rod 24, a first junction 241, a second junction 242 and a third junction 251 on its rear part, and has fourth junctions 26 provided on both sides of the front of the seat part 2. The backrest 3 is connected to the rear part of the seat part 2. The operation unit 4 comprises a transmission belt 41, a spring 42 and a first motor 43. The footrest 5 is pivoted to the front of the seat part 2 and has a second shaft rod 56. The second shaft rod 56 is interlocked with the transmission belt 41, the spring 42 and the first motor 43 to rotate. As the result, this invention provides excellent operational stability.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an extendable footrest for a chair, and mainly to an extendable footrest. [Background technology]

[0002] A known chair mainly comprises components such as a base, a seat and a backrest, and currently, in order to improve the comfort of supporting the legs when sitting, the seat is provided with a footrest that can be extended forward. The footrest can be folded under the seat in normal times to reduce the volume of the chair, and when sitting, the user can extend the footrest forward, so that the legs can be supported by the footrest in a straight line.

[0003] In order to enable the footrest to respond to the extension and retraction movement of the seat, in Patent Documents 1 and 2, for example, a connecting rod is installed between the footrest and the seat, one end of which is pivotally connected to a group of connecting rods of the footrest, and the connecting rod can be moved manually or electrically, and can drive the movement of the footrest being pushed forward to unfold it or pulled backward to fold it.

[0004] However, the operating method in which the connecting rod directly drives the footrest to push it forward or pull it backward had the risk of the pivot point between the connecting rod and the footrest being subjected to force and becoming worn out, and could lead to the pivoting of the pivot point becoming unsmooth or getting stuck. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] U.S. Patent No. 9,351,574 [Patent Document 2] U.S. Patent No. 10,123,620 Summary of the Invention [Problem to be solved by the invention]

[0006] SUMMARY OF THE PRESENT EMBODIMENT The present invention aims to provide an extendable footrest that provides smooth operation. [Means for solving the problem]

[0007] The present invention includes a base, a seat, a backrest, an actuating unit, and a footrest, the seat being installed above the base and having a first pivotal part installed at the rear, a first rod pivoted to the first pivotal part, and a first joint part and a second joint part fixedly installed to the first rod. A third joint part is installed on the seat, and a fourth joint part is installed on each side of the front of the seat. The backrest is joined to the rear of the seat. The actuating unit includes a transmission belt, a spring, and a first motor, one end of the transmission belt is combined with the first joint part of the seat. The spring has one end combined with the other end of the transmission belt and the other end combined with the third joint part of the seat. The first motor is installed at the position of the seat, and one end is joined with the second joint part of the seat. Furthermore, the footrest is provided with a second rod that is pivotally connected to the front of the seat and is combined to work in conjunction with the transmission belt, and the operation of the first motor drives the pivoting of the first rod, and by driving and moving the transmission belt, the pivoting of the second rod is driven and the spring is pulled, causing the footrest to unfold; further, the first motor can be operated in the reverse direction, causing the first rod, the transmission belt and the second rod to operate in the reverse direction, and the footrest can be folded up by the restoring force of the spring.

[0008] In the present invention, the transmission belt is a chain, and further, a gear that interlocks with the transmission belt is provided on the second shaft.

[0009] In the present invention, the fourth joint of the seat is provided with a first pivot hole and a second pivot hole, and the first pivot hole is an elongated hole. The footrest further includes two symmetrical connecting rods. The connecting rods include a first vertical piece, a second vertical piece, a third vertical piece, a fourth vertical piece, and a support plate. Both ends of the second rod are fixedly connected to the first piece. Furthermore, a connecting knob pivotally attached to the first pivot hole is inserted into one end of the first piece, so that the connecting knob can pivot and move in the first pivot hole. Furthermore, one end of the second piece or one end of the third piece is pivotally attached to two pivot positions of the other end of the first piece, and the other end of the second piece or the third piece is pivotally attached to two pivot positions of the support plate, and the second piece is provided with a third pivot hole. Furthermore, one end of the fourth piece is pivotally attached to the second pivot hole and the other end is pivotally attached to the third pivot hole, the length of the fourth piece is such that the volume can be reduced by folding the connecting rod group, and when the connecting rod group is unfolded from the folded state, the connecting knob can move within the first pivot hole, and the length of the fourth piece is shorter than the length over which the connecting knob does not move when the connecting rod group is unfolded.

[0010] In the present invention, the first pivot hole is an oblong hole, and the major axis of the hole corresponds substantially to the up-down direction.

[0011] In the present invention, a rear fixed rod is provided behind the seat, a third joint and a rear assembly are provided on the rear fixed rod, a lower joint is provided below the backrest and is pivotally connected to the first pivot part of the seat, and a lower pivot piece is provided below the backrest. The operating unit further includes a second motor, one end of which is connected to the rear assembly of the seat and the other end of which is connected to the lower pivot piece of the backrest, and the second motor can drive the backrest to fold upright or unfold backward.

[0012] In the present invention, the base is provided with a support, a connection frame is installed on the top of the support, and a movable frame is joined to the connection frame, and the seat is pivotally connected to the movable frame so that the seat can move up and down relative to the base.

[0013] In the present invention, the movable frame includes a rear pivot part, a front pivot part and an operating pivot part, the rear pivot part is pivotally connected to the connection frame, a front assembly part is provided in front of the seat part, the front assembly part is pivotally connected to the front pivot part of the movable frame, and the other end of the first motor is pivotally connected to the operating pivot part of the movable frame. Effect of the Invention

[0014] According to the present invention, the length of the fourth body piece becomes shorter when the footrest is folded, so that the footrest can be folded further toward the seat, thereby reducing the volume in the folded state and improving the texture; and, when the footrest is unfolded, the height of the footrest from the ground can be increased, so that the footrest can be folded and unfolded smoothly even when the base height is low.

[0015] According to the present invention, the first motor can drive the operation of the first rod, the transmission belt, the second rod and the spring, and the rotation of the second rod can drive the operation of the first half of the connecting rod group to unfold or fold the connecting rod group. Since the footrest is driven by the rotation of the second rod, it can have good smoothness and avoid the situation in which the joint between the connecting rod and the footrest becomes unsmooth or easily gets stuck due to wear, as occurs in known methods. [Brief description of the drawings]

[0016] [Figure 1] 1 is an exploded perspective view of a chair according to an embodiment of the present invention; [Diagram 2] FIG. 1 is a partial assembled perspective view of a chair according to one embodiment of the present invention. [Diagram 3] 1 is a conceptual side view showing a state in which the footrest and backrest of a chair according to an embodiment of the present invention are folded down; [Figure 4] 1 is a conceptual side view of an operation of unfolding a footrest of a chair according to an embodiment of the present invention. FIG. [Diagram 5]1 is an assembled side view of a chair showing the footrest and backrest of the chair in an unfolded state according to one embodiment of the present invention; FIG. [Figure 6] FIG. 2 is a side view showing a raised state of a chair according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS EXAMPLES

[0017] In the following embodiments, components having similar functions in one embodiment of the present invention are denoted by the same reference numerals, and some pivot members are omitted in the drawings. Figs. 1 to 3 are an exploded perspective view, a partially assembled perspective view, and a conceptual side view of one embodiment of the present invention, respectively. The embodiment of the present invention includes a base 1, a seat 2, a backrest 3, an operating unit 4, and a footrest 5. The base 1 includes a support column 11, and a connection frame 12 is installed on the top of the support column 11, and a movable frame 13 is joined to the connection frame 12. The movable frame 13 includes a rear pivot part 131, a front pivot part 132, and an operating pivot part 133.

[0018] The seat 2 includes a first frame 21 and a second frame 22. A first pivot 23 is provided at the rear of the first frame 21. A first shaft rod 24 is pivoted to the first pivot 23. A first joint 241 and a second joint 242 are fixedly provided to the first shaft rod 24. A rear fixed rod 25 is provided at the rear of the first frame 21. A third joint 251 and a rear assembly part 252 are provided to the rear fixed rod 25. A hook rod 253 is provided to the third joint 251. Fourth joints 26 are provided on both sides of the front of the first frame 21. A first pivot hole 261 and a second pivot hole 262 are provided in the fourth joint 26. The first pivot hole 261 is an elongated elliptical hole, and its major radius corresponds approximately to the vertical direction. Furthermore, a front assembly part 27 is installed in front of the first frame 21, and the front assembly part 27 is pivotally mounted to the front pivot part 132 of the movable frame 13. Furthermore, the second frame 22 is installed above the first frame 21, and can provide a pad (not shown) for assembling and mounting.

[0019] A lower joint 31 is provided below the backrest 3 and is pivotally connected to the first pivot portion 23 at the rear of the seat 2 . Further below the backrest 3 , a lower pivot piece 32 is provided.

[0020] The operating unit 4 includes a transmission belt 41, a spring 42, a first motor 43, and a second motor 44. The transmission belt 41 may be a chain, but may be another type of belt body in other embodiments, and one end of the transmission belt 41 is combined with the first joint 241 of the seat 2. Furthermore, one end of the spring 42 is combined with the other end of the transmission belt 41, and the other end is combined with the hook rod 253 of the third joint 251 of the seat 2. Furthermore, one end of the first motor 43 is connected with the second joint 242 of the first shaft rod 24 of the seat 2, and the other end is connected with the operating pivot 133 of the movable frame 13, so that the first motor 43 can drive the pivot of the first shaft rod 24 and the operation of the transmission belt 41. Furthermore, one end of the second motor 44 is connected to the rear assembly portion 252 of the seat portion 2, and the other end is connected to the lower pivot piece 32 of the backrest 3, so that the second motor 44 can drive the backrest 3 to fold upright or unfold backward.

[0021] The footrest 5 includes two symmetrical connecting rods 50 and a second shaft rod 56. The connecting rods 50 include a first vertical piece 51, a second vertical piece 52, a third vertical piece 53, a fourth vertical piece 54, and a support plate 55. A joint knob 511 pivotally attached to the first pivot hole 261 is inserted into one end of the first piece 51, so that the joint knob 511 can pivot and move in the first pivot hole 261. Furthermore, one end of the second piece 52 and the third piece 53 are pivotally attached to two pivot positions on the other end of the first piece 51, and the other ends of the second piece 52 and the third piece 53 are pivotally attached to two pivot positions on the support plate 55, and the second piece 52 is provided with a third pivot hole 521. Furthermore, one end of the fourth piece 54 is pivotally attached to the second pivot hole 262 of the seat 2, and the other end is pivotally attached to the third pivot hole 521. Furthermore, both ends of the second shaft rod 56 are fixedly connected to the first piece 51 of the connecting rod group 50, and a gear 561 is provided on the surface of the second shaft rod 56 so as to be connected to the transmission belt 41. Furthermore, the length of the fourth piece 54 is such that the connecting rod group 50 can be folded toward the seat 2 to reduce its volume, and when the connecting rod group 50 is unfolded from the folded state, the connecting tab 511 can move upward within the first pivot hole 261, so that the connecting rod group 50 can be unfolded smoothly, and the fourth piece 54 can have a relatively short length, which is shorter than the length at which the connecting tab 511 does not move when the connecting rod group 50 is unfolded.

[0022] Please refer to Fig. 4. Fig. 4 is a conceptual diagram of the unfolding operation of the footrest according to one embodiment of the present invention. In the figure, the transmission belt is not shown. In one embodiment of the present invention, since the length of the fourth piece 54 is relatively short, when the footrest 5 of this embodiment is unfolded at about 20 to 45 degrees, the positions of the corresponding pivot axes of the fourth piece 54 and the first piece 51 differ as shown by the dotted line, and the footrest cannot be smoothly pivoted. Therefore, the positions of the joint knob 511 of the first piece 51 and the first pivot hole 261 can be moved correspondingly, and the positions of the pivot axes can be made to correspond to each other so that the connecting rod group 50 can be unfolded smoothly.

[0023] In one embodiment of the present invention, the length of the fourth piece 54 becomes shorter when the footrest 5 is folded, so that the footrest 5 can be folded further towards the seat 2, thereby reducing the volume of the folded state and improving the texture. In addition, the height of the footrest 5 from the ground can be increased when the footrest 5 is unfolded, so that the footrest 5 can be folded and unfolded smoothly even when the height of the base 1 is low.

[0024] Please refer to Figures 1, 2, 4 and 5. Figure 5 is a conceptual diagram of the footrest and backrest according to an embodiment of the present invention in an unfolded state. When the footrest 5 according to an embodiment of the present invention is unfolded from the folded state, the first motor 43 can be extended, and the first motor 43 drives the first rod 24 to rotate, and the first rod 24 drives the transmission belt 41 to move, and can also drive the rotation of the second rod 56 and the pulling action of the spring 42. Furthermore, the rotation of the second rod 56 drives the operation of the first piece 51 of the connecting rod group 50 to unfold the connecting rod group 50, so that it can abut against the legs of the human body.

[0025] The footrest 5 according to the embodiment of the present invention is driven by the rotation of the second shaft rod 56, and is not pushed by a connecting rod (not shown) as in the known method, so that the footrest 5 can be deployed smoothly and the situation where the joint between the connecting rod and the footrest becomes unsmooth or easily stuck due to wear as in the known method can be avoided. Furthermore, the embodiment of the present invention can operate the second motor 44 to drive the backrest 3 to tilt it backward, improving the sitting comfort.

[0026] 1 to 3. In one embodiment of the present invention, the second motor 44 is operated to fold the backrest 3 upright, and the first motor 43 is contracted to drive the first shaft 24 to rotate in the reverse direction, and the elastic restoring force of the spring 42 pulls the transmission belt 41 to move in the reverse direction, driving the second shaft 56 to rotate in the reverse direction, so that the footrest 5 is folded. When the footrest 5 is folded, the joint tab 511 moves in the first pivot hole 261, so that the folding operation can be smooth, and the footrest 5 is folded further toward the seat 2, so that the volume of the folded state can be reduced.

[0027] Please refer to Figure 6. It is a conceptual diagram of the seat in an embodiment of the present invention in a raised state. In the present invention, the first motor 43 can be contracted to drive the movable frame 13 to displace relative to the base 1, and the movable frame 13 can drive the seat 2 to rise and pull up the rear, making it easier for the seated person to stand up. Furthermore, the footrest 5 can be folded close to the seat 2, so that the footrest 5 does not protrude too far outside the seat 2, and excellent convenience can be provided when standing up.

[0028] As described above, the present invention can have good smoothness of operation and good consistency of the footrest, but the base of the present invention can be directly connected to the seat and does not necessarily have to be provided with a movable frame, and the other end of the first motor can be directly connected to the seat, and the angle of the backrest can also be manually changed relative to the seat and does not necessarily have to be provided with a second motor. As described above, the present invention is not limited to the above-described embodiment, and can be embodied in various forms without departing from the spirit and scope of the present invention. [Explanation of symbols]

[0029] 1 Base 11 Posts 12 Connection Frame 13 Movable Frame 131 Rear pivot joint 132 Front pivot joint 133 Actuation pivot joint 2 Seat part 21 1st Frame 22 2nd Frame 23 1st pivot joint 24 1st axis rod 241 1st joint 242 Second joint 25 Rear fixed rod 251 Third joint 252 Rear assembly section 253 Hook rod 26 4th joint 261 1st pivot hole 262 2nd pivot hole 27 Front assembly section 3. Backrest 31 Lower joint 32 Lower pivot piece 4. Operating unit 41 Transmission belt 42 Spring 43 First Motor 44 Second Motor 5 Footrest 50 consecutive rod group 51 First piece 511 Joining hole 52 Second piece 521 3rd pivot hole 53 Third piece 54 4th piece 55 Support plate 56 2nd axis rod 561 Gears

Claims

1. Base (1), a seat (2), the seat being disposed above the base, the seat having a first pivot part (23) disposed at the rear thereof, a first shaft rod (24) pivoted to the first pivot part, a first joint part (241) and a second joint part (242) fixedly disposed to the first shaft rod, a third joint part (251) disposed on the seat, and a fourth joint part (26) disposed on each of the front sides of the seat; A backrest (3) joined to the rear of the seat; an actuation unit (4) including a transmission belt (41), a spring (42) and a first motor (43), one end of the transmission belt being combined with a first joint of the seat, one end of the spring being combined with the other end of the transmission belt and the other end being combined with the third joint of the seat, the first motor being installed at the position of the seat and one end being connected to the second joint of the seat; A footrest (5) comprising a second rod (56) pivotally connected to the front of the seat and combined to link with the transmission belt, wherein the operation of the first motor drives the pivoting of the first rod, and the operation of the transmission belt drives the pivoting of the second rod, thereby pulling the spring and causing the footrest to unfold, and further, the operation of the first motor in the reverse direction can cause the first rod, the transmission belt and the second rod to operate in the reverse direction, and the footrest can be folded by the restoring force of the spring.

2. 2. The footrest of a chair according to claim 1, wherein the transmission belt is a chain, and a gear (561) interlocking with the transmission belt is provided on the second shaft.

3. The fourth joint of the seat is provided with a first pivot hole (261) and a second pivot hole (262), the first pivot hole being an elongated hole, the footrest further includes two symmetrical connecting rod groups (50), the connecting rod group including a first vertical piece (51), a second vertical piece (52), a third vertical piece (53), a fourth vertical piece (54) and a support plate (55), both ends of the second rod are fixedly connected to the first piece, one end of the first piece is inserted with a connecting knob (511) pivotally attached to the first pivot hole, the connecting knob can pivot and move in the first pivot hole, and one end of the second piece or one end of the third piece is fixed to the first piece. A footrest for a chair as described in claim 1, wherein each of the first and third pieces is pivotally attached to two pivot positions on the other end of the first piece, the other end of the second piece or the third piece is pivotally attached to two pivot positions on the support plate, the second piece is provided with a third pivot hole (521), one end of the fourth piece is pivotally attached to the second pivot hole and the other end is pivotally attached to the third pivot hole, the length of the fourth piece is such that the volume can be reduced by folding the connecting rod group, when the connecting rod group is unfolded from a folded state, the connecting knob can move within the first pivot hole, and the length of the fourth piece is shorter than the length over which the connecting knob does not move when the connecting rod group is unfolded.

4. 4. The footrest of a chair according to claim 3, wherein the first pivot hole is an elliptical hole, the major axis of which corresponds approximately to the up-down direction.

5. The footrest of the chair described in claim 1, wherein a rear fixed rod (25) is provided at the rear of the seat, the third joint and the rear assembly part (31) are provided on the rear fixed rod, a lower joint part (32) pivotally connected to the first pivot part of the seat is provided below the backrest, and a lower pivot piece is provided below the backrest, and the operating unit further includes a second motor (44), one end of which is connected to the rear assembly part (252) of the seat and the other end of which is connected to the lower pivot piece of the backrest, and the second motor can drive the backrest to fold upright or unfold backward.

6. 2. The footrest of a chair as described in claim 1, wherein the base has a support (11), a connecting frame (12) is installed on the top of the support, a movable frame (13) is joined to the connecting frame, and the seat is pivotally connected to the movable frame, so that the seat can be raised and lowered relative to the base.

7. The footrest of a chair as described in claim 6, wherein the movable frame has a rear pivot part (131), a front pivot part (132) and an operating pivot part (133), the rear pivot part is pivotally connected to the connection frame, a front assembly part (27) is installed in front of the seat part, the front assembly part is pivotally connected to the front pivot part of the movable frame, and the other end of the first motor is pivotally connected to the operating pivot part of the movable frame.

Images