BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a chair, more particularly to a composite chair.

2. Description of the Related Art

Modern people value the quality of life, which is reflected in their requirements for daily utilities. These utilities must not only provide better performance but also aid in health. Taking chairs for example, most modern chairs are designed with a backrest to support a user's back. Unfortunately, most backrests are plate-shaped and tend to cause discomfort and lead to posture problems.

In view of this, vendors began developing ergonomic chairs similar to the conventional chair 1 shown in FIG. 1. The conventional chair 1 includes a support frame 11, a backrest unit 12 connected to the support frame 11, and a seat unit 13 connected to the support frame 11. The backrest unit 12 includes an arcuate rod 121, two coupling members 122 respectively sleeved on opposite ends of the arcuate rod 121, and two backrest pads 123 respectively connected to the coupling members 122. The backrest pads 123 are rotatable in upward, downward, left and right directions relative to the support frame 11, and the distance between the backrest pads 123 is adjustable by moving the coupling members 122 to different positions along the arcuate rod 121. Through this configuration, the user's back and waist muscles are comfortably supported by the backrest pads 123.

However, even though the conventional chair 1 provides more comfort, it fails to provide support to the user's remaining body parts. In addition, most users such as office workers remain seated for an extended period of time without exercise, causing posture problems that affect health. Therefore, there is room for improvement regarding the functionality of the conventional chair 1.

SUMMARY OF THE INVENTION

Therefore, the object of the present invention is to provide a composite chair that can eliminate the aforesaid drawbacks of the prior art.

According to the present invention, there is provided a composite chair adapted for permitting a user to seat thereon. The composite chair includes a base unit and a seat unit. The seat unit includes a seat body and a pushing member. The seat body is mounted on the base unit and is adapted for supporting the user's buttocks. The pushing member is fixedly mounted on a rear end of the seat body. The seat body is pivotable relative to the base unit for inclining the pushing member to push the user's waist forward.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiment with reference to the accompanying drawings, of which:

FIG. 1 is a perspective view of a conventional chair;

FIG. 2 is a perspective view of the preferred embodiment of a composite chair according to the present invention;

FIG. 3 is a side schematic view of the preferred embodiment for illustrating a user permitted to sit thereon;

FIG. 4 is a side schematic view of the preferred embodiment for illustrating a seat body inclined forward;

FIG. 5 is a side schematic view of the preferred embodiment for illustrating the seat body inclined backward;

FIG. 6 is a top schematic view of the preferred embodiment for illustrating support units and armrest members in a retracted position;

FIG. 7 is a top schematic view of the preferred embodiment for illustrating the support units and armrest members in an expanded position;

FIG. 8 is a side schematic view of the preferred embodiment for illustrating the seat body and a backrest unit inclined forward; and

FIG. 9 is a side schematic view of the preferred embodiment for illustrating the backrest unit inclined backward.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 2 and 3, the preferred embodiment of a composite chair according to the present invention is adapted for permitting a user 9 to sit thereon, and includes a base unit 2, a seat unit 3, a shifting device 4, a backrest unit 5, an inflatable unit 6 and an armrest unit 7.

The base unit 2 includes two front legs 21 spacedly disposed, two rear legs 22 (only one can be seen) spacedly disposed, a connecting plate 23 interconnecting the front and rear legs 21, 22, and a top board 24 interconnecting the front legs 21 and disposed below the shifting device 4.

The seat unit 3 includes a seat body 31 and a pushing member 32. The seat body 31 is mounted on the base unit 2 and is adapted for supporting the buttocks of the user 9. The pushing member 32 is fixedly mounted on a rear end of the seat body 31. The seat body 31 is pivotable relative to the base unit 2 for inclining the pushing member 32 to push the waist of the user 9 forward. The seat unit 3 further includes a first power source 33 and a first driving member 34 that are mounted on the connecting plate 23. The first driving member 34 drives a pivoting motion of the seat body 31 while the first power source 33 provides power to the first driving member 34. In this embodiment, the first driving member 34 is a cam; by controlling the rotation of the cam, the seat body 31 can be disposed horizontally (see FIG. 3), inclined forward (see FIG. 4) and inclined backward (see FIG. 5) relative to the base unit 2. The first driving member 34 may also be a pneumatic cylinder or a hydraulic cylinder and is not limited to what is disclosed herein.

Referring to FIGS. 3 and 6, the shifting device 4 is pivotally mounted on the base unit 2, is disposed in front of the seat unit 3, and includes two support units 41 adapted for respectively supporting the thighs of the user 9. The support units 41 are movable relative to the base unit 2 between a retracted position (see FIG. 6), where the support units 41 are close to each other, and an expanded position (see FIG. 7), where the support units 41 are away from each other. The top board 24 of the base unit 2 is formed with two arcuate slide grooves 241 spaced apart from each other. Each of the support units 41 of the shifting device 4 includes a support plate 411, and a limiting member 412 that protrudes downward from the support plate 411 for engaging slidably a respective one of the slide grooves 241 so as to be limited therein, thus allowing the support plates 411 of the support units 41 to be movable between the retracted and expanded positions.

With reference to FIGS. 2 and 3, the backrest unit 5 is mounted on and pivotable relative to the base unit 2 in a front-rear direction for moving the back of the user 9. The backrest unit 5 includes a second driving member 51, a back board 52 and a second power source 53. The second driving member 51 is pivotally mounted between the rear legs 22 of the base unit 2. The back board 52 is mounted on the second driving member 51 and is formed with two concave receiving portions 521 facing the user 9. The second power source 53 is mounted on the base unit 2 for providing power to the second driving member 51. In this embodiment, the second driving member 51 is a motor, and the power source 53 is mounted on one of the rear legs 22; these configurations are not limited to what is disclosed herein.

Referring to FIGS. 3 and 7, the armrest unit 7 is mounted on and vertically movable relative to the backrest unit 5, and is adapted for supporting respectively the arms of the user 9. The armrest unit 7 includes a connecting member 71 and two armrest members 72. The connecting member 71 is mounted on the backrest unit 5 and is vertically movable relative to the backrest unit 5. The armrest members 72 are respectively and pivotally connected to left and right ends of the connecting member 71 and are horizontally pivotable relative to the connecting member 71. The armrest unit 7 further includes two third driving members 73 and a third power source 74. The third driving members 73 are spacedly mounted on the back board 52 of the backrest unit 5 for controlling movement of the connecting member 71 in a top-bottom direction while the third power source 74 provides power to the third driving members 73. Each of the third driving members 73 may be a pneumatic cylinder or a hydraulic cylinder and is not limited to what is disclosed herein.

Referring again to FIGS. 2 and 3, the inflatable unit 6 is mounted on a side of the backrest unit 5, faces the user 9 and is inflatable for supporting the back of the user 9. The inflatable unit 6 includes two inflatable members 61 and an inflating-deflating component 62. Each inflatable member 61 is received in a respective one of the receiving portions 521 of the backrest unit 5. The inflating-deflating component 62 is mounted on the back board 52 for inflating the inflatable members 61 to support the back of the user 9, and deflating the inflatable members 61 when necessary (e.g., when not in use). The inflating-deflating component 62 has a built-in power source (not shown). It should be noted that due to the viewing angle, only one of the inflatable members 61 is shown in the side schematic views.

With reference to FIG. 3, the composite chair of this invention is to be used as an ordinary chair that permits a user 9 to sit thereon, where the two third driving members 73 are operated to adjust the height of the connecting member 71 for positioning the armrest members 72 at the appropriate height. When the first power source 33 drives rotation of the first driving member 34 such that the seat body 31 is inclined forward as shown in FIG. 8, the seat body 31 will synchronously drive the pushing member 32 to tilt forward so as to push the waist and hips of the user 9. In the meantime, the second power source 53 of the backrest unit 5 drives the second driving member 51 to rotate and thereby tilt the back board 52 forward, thus pushing the upper body of the user 9 slightly forward. Simultaneously, the inflating-deflating component 62 of the inflatable unit 6 charges air into the inflatable members 61 and once inflated, the back of the user 9 is pushed forward and supported by the same. This coordinated motion raises the chest of the user 9 forward and upward so as to stretch the abdominal, waist and back muscles of the user 9; at this time, the arms and legs of the user 9 will naturally stretch outward to move the two armrest members 72 outwardly and not move the support plates 411 from the retracted position to the expanded position as shown in FIG. 7. It should be noted that the pushing member 32 of the seat unit 3 has an inverted trapezoid shape that corresponds to the pelvis of the user 9 for better pushing results.

When the first driving member 34 rotates back to the position shown in FIG. 3, the seat body 31 is disposed horizontally relative to the base unit 2, and the inflating-deflating component 62 discharges the air from the inflatable members 61 such that the body of the user 9 returns to its initial/original posture.

Referring to FIG. 9, since the back board 52 of the backrest unit 5 is independently pivotable relative to the base unit 2 as controlled by the second driving member 51, which is powered by the second power source 53, the user 9 can train his/her abdominal and back muscles if desired. For example, in FIG. 9, the back board 52 is inclined backward, allowing the upper body of the user 9 to face slightly upward, thus stretching the abdominal and thigh muscles (e.g. quadriceps). When the back board is inclined backward, the inflating-deflating component 62 charges air into the inflatable members 61 for supporting the back of the user 9. In practice, the seat body 31, the pushing member 32 and the back board 52 can simultaneously incline backward.

Referring back to FIGS. 2 and 3, each of the support plates 411 of the shifting device 4 and the armrest members 72 of the armrest unit 7 are moved by the user 9, allowing the user 9 to train his/her arm and leg muscles separately. Moreover, operations of the first, second and third power sources 33, 53, 74, and the inflating-deflating component 62 can be controlled by a single controller (not shown), which may independently activate these components or control them in a predetermined sequence, e. g., activating the first power source 33, the second power source 53 and the inflating-deflating component 62 in sequence. Since these controlling methods are well known to those skilled in the art, they will not be further detailed herein.

In sum, in the composite chair of this invention, through the pivoting of the seat body 31 of the seat unit 3 relative to the base unit 2, the pushing member 32 will push the waist and hips of the user 9 and the pushing effect is enhanced due to the inverted trapezoid shape (which corresponds to the shape of the pelvis) of the pushing member 32. The inflatable members 61 of the inflatable unit 6 can be inflated to push and support the back of the user 9 to raise the chest of the user 9 up and forward, thus stretching the back and abdominal muscles of the user 9 and strengthening the core of the user 9. Moreover, each of the seat unit 3, the shifting device 4, the backrest unit 5, the inflatable unit 6 and the armrest unit 7 can be operated independently, allowing the user 9 to train and/or rehabilitate the muscle group of a designated body portion according to the needs of the user 9. Therefore, the purpose of this invention is served.

While the present invention has been described in connection with what is considered the most practical and preferred embodiment, it is understood that this invention is not limited to the disclosed embodiment but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.