CN112568637B - Chair - Google Patents

Abstract

A chair includes a base unit, a cushion unit, and a back unit. The chair also includes an adjustment unit. The adjusting unit comprises a base module connected with the base column unit and a connecting module which can rotate around a first axis and is connected with the base module in a positioning way. The chair back unit can rotate around a second axis parallel to the first axis and is connected to one end of the connecting module opposite to the base module in a positioning way. The connecting module can rotate around the first axis relative to the base module to enable the chair back unit to move between an approaching position and a separating position relative to the base column unit along the first axis, so that the distance from the front edge of the chair cushion unit to the chair back unit can be adjusted, and the chair back unit can be adjusted to an angle suitable for leaning by rotating relative to the connecting module by adjusting, so that users with different shapes can sit.

Description

Chair

Technical field

The present invention relates to a chair, in particular to a chair that can adjust the distance from the front edge of the seat cushion to the back of the chair.

Background technique

The height and weight of developing children increase rapidly. The average height of six-year-old school children in Taiwan, China is 116.7 cm, and the average height of 12-year-old school children is 151.5 cm, a growth rate of 29.8%; the average weight of six-year-old school children is 116.7 cm. 21.8 kg, the average weight of twelve-year-old schoolchildren is 46.1 kg, and the growth rate is as high as 111.5%, showing that the body shape of developing children changes considerably.

Therefore, a six-year-old schoolchild and a 12-year-old schoolchild have different chair size requirements. As far as the distance from the front edge of the seat cushion of the chair to the back of the chair is concerned, a six-year-old schoolchild needs a smaller distance due to his smaller body size, while a 12-year-old schoolchild needs a larger distance due to his larger body size. However, a general chair can only adjust the height of the seat cushion relative to the ground, but cannot adjust the distance from the front edge of the seat cushion to the back of the chair, so it cannot be suitable for school children of different ages. In this regard, ordinary parents often purchase chairs of different sizes as their children grow up. However, used chairs usually have to be discarded because they are too small, which results in waste.

Contents of the invention

The object of the present invention is to provide a chair that can accommodate users of different body shapes.

The chair of the present invention includes a base unit, a chair cushion unit, and a chair back unit. The seat cushion unit is connected to the base column unit. The seat back unit is disposed above the seat cushion unit. The chair further includes an adjustment unit, which includes a base module connected to the base column unit, and a connection module capable of rotating around a first axis and being positioned and connected to the base module. The seat back unit can rotate around a second axis parallel to the first axis and is positionally connected to an end of the connection module opposite to the base module. The connection module can rotate about the first axis relative to the base module to move the seat back unit relative to the base column unit along the first axis between an approaching position and a far away position. In the approach position, the back unit is relatively adjacent to the base unit. In the remote position, the seat back unit is relatively far away from the base unit.

In the chair of the present invention, the connection module of the adjustment unit is formed with a first pivot portion pivoted to the base module along the first axis for the chair back unit to be pivoted along the second axis. a second pivot portion, and a first rotating portion and a second rotating portion that respectively connect the base module and the chair back unit and can rotate synchronously and respectively around the first axis and the second axis. department. When the connection module rotates around the first axis relative to the base module, the first rotating part will rotate around the first axis and synchronously drive the second rotating part around the second axis. Rotate to drive the seat back unit to rotate around the second axis relative to the connection module.

In the chair of the present invention, the first pivot part, the first rotation part, the second rotation part and the second pivot part of the adjustment unit together form a four-bar linkage mechanism, and the first rotation part and the second rotation part The distance between the parts is fixed.

In the chair of the present invention, the connection module of the adjustment unit has a base member, a first pivot shaft and a second pivot shaft that are respectively passed through the base member along the first axis and the second axis, and are formed on the base member. The base member has a first groove and a second groove respectively around the first axis and the second axis, respectively rotatable around the first axis and the second axis and slidably penetrated respectively. A first rotation axis and a second rotation axis in the first groove and the second groove, and a connecting rod pivotally connected between the first rotation axis and the second rotation axis. The first pivot part and the second pivot part are axis-disposed on the base member. The first pivot has the first pivot portion exposed outside the base member. The second pivot has a second pivot portion exposed outside the base member. The first rotating shaft has the first rotating part exposed outside the base member. The second pivot has the second rotating portion exposed outside the base member.

In the chair of the present invention, the first groove of the adjustment unit is arc-shaped and has a first approach end relatively adjacent to the base column unit, and is opposite to the first approach end and relatively far away from the base column. The first remote end of the unit. When the seat back unit is in the approach position, the first rotation axis is located at the first approach end. When the seat back unit is in the remote position, the first rotation axis is located at the first remote end.

In the chair of the present invention, the second groove of the adjustment unit is arc-shaped and has a second approach end relatively adjacent to the base column unit, and is opposite to the second approach end and relatively far away from the base column. The second remote end of the unit. When the seat back unit is in the approach position, the second rotation axis is located at the second approach end. When the seat back unit is in the remote position, the second rotation axis is located at the second remote end.

In the chair of the present invention, the base member of the adjustment unit has a first plate portion, a second plate portion spaced apart from the first plate portion along a second axial direction perpendicular to the first axial direction, and a second plate portion connected to the first plate portion. A surrounding plate portion between a plate portion and the second plate portion. The first plate portion, the second plate portion and the surrounding plate portion cooperate to define a chamber for the connecting rod to extend. The first groove and the second groove are formed on the first plate part and communicate with the chamber.

In the chair of the present invention, the connection module of the adjustment unit also has a first guide groove and a second guide groove. The first guide groove and the second guide groove are formed on the second plate part and correspond to the first groove and the second groove respectively, and are respectively used for the first rotation shaft and the The second rotation axis is slidably disposed.

In the chair of the present invention, the base module of the adjustment unit has a first joint plate and a second joint plate spaced apart along the first axis. The first plate portion has a first end face relative to the first joining plate. The chair also includes a positioning unit. The positioning unit includes an engaging portion provided on the first end surface and surrounding the first axis, and a locking portion provided on the first joint plate and being concave and convex complementary to the engaging portion. The locking part can be operated to move along the first axis relative to the embedding part between a positioning position and a disengagement position. In the positioning position, the clamping portion approaches the first end surface and contacts the inserting portion, so that the connection module is positioned non-rotatably relative to the first joint plate. In the disengaged position, the locking part is relatively far away from the embedding part, and the connection module can rotate around the first axis relative to the first joint plate.

In the chair of the present invention, the base column unit includes a column extending upward, and is connected between the column and the base module and can be operated to drive the base module to move up and down along the column and generate Positioning sliding seat.

The beneficial effect of the present invention is that by arranging the connection module, when the connection module rotates relative to the base module, it can drive the seat back unit relative to the base column unit along the third axis. An axis moves between the approaching position and the far away position, so the distance from the front edge of the chair cushion unit to the chair back unit can be adjusted, and then the chair back unit can be adjusted relative to the The connection module rotates to adjust the chair back unit to a suitable angle for leaning, so it can be used by users of different body shapes.

Description of the drawings

Figure 1 is a perspective assembly view of an embodiment of the chair of the present invention;

Figure 2 is an exploded perspective view of the embodiment;

Figure 3 is a three-dimensional exploded view of the embodiment viewed from another angle;

Figure 4 is a schematic right view of a connection module of the embodiment;

Figure 5 is a cross-sectional view taken along line V-V of Figure 1 , illustrating a locking portion in a disengaged position relative to an embedding portion;

Figure 6 is a view similar to Figure 5 , illustrating that the clamping part is in a positioning position relative to the embedding part;

Figure 7 is a right view of the embodiment, illustrating a seat back unit in a remote position relative to a base unit along a first axis;

FIG. 8 is a view similar to FIG. 7 , illustrating that the seat back unit is in an approaching position relative to the base column unit along the first axis.

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings and examples.

Referring to Figures 1, 2, and 3, an embodiment of the chair of the present invention includes a base unit 2, a seat cushion unit 3, a chair back unit 4, an adjustment unit 5, and a positioning unit 6.

Define a first axis X, a second axis Y perpendicular to the first axis X, and a third axis Z perpendicular to the first axis X and the second axis Y.

The base column unit 2 includes an upwardly extending column 21, and a sliding base 22 connected to the column 21 and operable to move up and down along the column 21 and position.

The seat cushion unit 3 is connected to the pillar 21 .

The seat back unit 4 is disposed above the seat cushion unit 3 .

The adjustment unit 5 includes a base module 51 connected to the sliding seat 22 and capable of being driven by the sliding seat 22 to move up and down along the pillar 21 and positioning, and a base module 51 capable of rotating around a first axis L1 The connection module 9 is rotated and positioned to be connected to the base module 51 .

Referring to Figures 2, 3, and 4, the seat back unit 4 can rotate around a second axis L2 parallel to the first axis L1 and is positionally connected to the connection module 9 opposite to the base module. 51 on one end.

The base module 51 has a first joint plate 7 and a second joint plate 8 spaced apart along the first axis L1. The connection module 9 is located between the first joint plate 7 and the second joint plate 8 .

The first joint plate 7 has a first base 71, a first through hole 72 penetrating the first base 71 along the first axis L1, and a first through hole 72 that can rotate around the first axis L1 and can rotate along the first axis L1. The first axis L1 movably extends from the adjusting portion 73 of the first through hole 72 , and one is exposed outside the first base portion 71 and is connected to the adjusting portion 73 and can drive the adjusting portion 73 around the first The holding portion 74 rotates along the axis L1, and a pivot groove 75 is recessed on the side of the adjusting portion 73 corresponding to the connection module 9 and extends along the first axis L1. In this embodiment, the first base 71 is made of plastic material.

Referring to Figures 2, 5, and 6, the first through hole 72 has a small aperture area 721 adjacent to the connection module 9, and a large aperture area opposite to the small aperture area 721 and having an aperture larger than the small aperture area 721. an aperture area 722, and a connection area 723 connecting the small aperture area 721 and the large aperture area 722.

The first base 71 has an abutment area 711 that defines the connection area 723, and a surrounding area 712 that surrounds the large aperture area 722. The surrounding area 712 is formed with an internal thread 713 .

An external thread 732 corresponding to the internal thread 713 is formed on the outer peripheral surface of the adjustment portion 73 .

Referring to Figures 2, 3, and 4, the connection module 9 has a base member 91, and a first pivot 92 that passes through the base member 91 along the first axis L1 and the second axis L2 respectively. With a second pivot 93, a first groove 94 and a second groove 95 formed on the base member 91 and respectively surrounding the first axis L1 and the second axis L2, they can respectively surround the first axis L1 and the second axis L2. The first axis L1 and the second axis L2 rotate and are slidably inserted through a first rotation shaft 96 and a second rotation shaft 97 respectively in the first groove 94 and the second groove 95 , a connecting rod 98 pivotally connected between the first rotation axis 96 and the second rotation axis 97, and is formed on the base member 91 and corresponds to the first groove 94 and the second rotation axis respectively. The groove 95 provides a first guide groove 99 and a second guide groove 90 for the first rotation shaft 96 and the second rotation shaft 97 to be slidably provided respectively.

The base member 91 has a first plate portion 911, a second plate portion 912 spaced apart from the first plate portion 911 along the second axis Y, and connects the first plate portion 911 and the first plate portion 911. The surrounding plate portion 913 is between the second plate portions 912. The first plate portion 911 , the second plate portion 912 and the surrounding plate portion 913 cooperate to define a receiving chamber 914 for the connecting rod 98 to extend. The first groove 94 and the second groove 95 are formed in the first plate portion 911 and communicate with the chamber 914 . The first guide groove 99 and the second guide groove 90 are formed on the second plate portion 912 and communicate with the accommodation chamber 914 .

The first plate portion 911 has a first end surface 915 relative to the first joint plate 7 .

The first pivot 92 passes through the first plate portion 911 and the second plate portion 912 of the base member 91 , and has two pivot shafts located at both ends and exposed outside the base member 91 and along the The first axis L1 is pivoted to the first pivot portion 921 of the base module 51 . One of the first pivot portions 921 adjacent to the first joint plate 7 extends from the pivot groove 75 .

The second pivot 93 passes through the first plate portion 911 and the second plate portion 912 of the base member 91 and has two pivot shafts located at both ends and exposed outside the base member 91 for the The second pivot portion 931 of the seat back unit 4 is pivoted along the second axis L2.

The first rotating shaft 96 passes through the first groove 94 and the first guide groove 99 of the base member 91 , and has two shafts located at both ends and exposed outside the base member 91 and capable of being wound around. The first axis L1 is rotatably connected to the first rotating part 961 of the base module 51 .

The second rotating shaft 97 passes through the second groove 95 and the second guide groove 90 of the base member 91 and has two shafts located at both ends and exposed outside the base member 91 and capable of being wound around. The second axis L2 is rotatably connected to the second rotating portion 971 of the base module 51 . In this embodiment, the first rotating part 961 and the second rotating part 971 can rotate synchronously around the first axis L1 and the second axis L2 respectively.

The first groove 94 is arc-shaped and has a first approach end 941 relatively adjacent to the base column unit 2, and a first approach end 941 opposite to the base column unit 2 and relatively far away from the base column unit. The first remote end 942 of 2.

The second groove 95 is arc-shaped and has a second approach end 951 relatively adjacent to the base column unit 2, and opposite to the second approach end 951 and relatively away from the base column unit 2. The second remote end 952.

The first pivot portion 921 and the second pivot portion 931 are axially provided on the base member 91 . Each first pivot part 921 and its corresponding first rotation part 961, corresponding second rotation part 971 and corresponding second pivot part 931 together form a four-bar linkage mechanism, and each first rotation part 961 and its respective The distance between the corresponding second rotating parts 971 is fixed.

Referring to Figures 4, 7, and 8, the connection module 9 can rotate around the first axis L1 relative to the base module 51 so that the seat back unit 4 can be positioned along any direction relative to the base column unit 2. The first axis X moves between an approach position (see Figure 7) and a away position (see Figure 8). In the approaching position, the seat back unit 4 is relatively adjacent to the base column unit 2, the first rotation axis 96 is located at the first approaching end 941 (see the solid line position in Figure 4), and the The second rotation axis 97 is located at the second approach end 951 (see the solid line position in Figure 4). In the far away position, the seat back unit 4 is relatively far away from the base column unit 2, the first rotation axis 96 is located at the first far away end 942 (see the imaginary line position in Figure 4), and the third The two rotation shafts 97 are located at the second remote end 952 (see the imaginary line position in Figure 4).

Referring to Figures 2, 5, and 6, the positioning unit 6 includes an inserting portion 61 disposed on the first end surface 915 of the base member 91 and surrounding the first axis L1, and an inserting portion 61 disposed on the first end surface 915 of the base member 91. The engaging plate 7 is formed into a concave and convex complementary engaging portion 62 with the engaging portion 61 . In this embodiment, the clamping portion 62 is made of plastic material.

The locking part 62 can be operated to move along the first axis L1 relative to the insertion part 61 between a positioning position (see Figure 5) and a disengagement position (see Figure 6). In the positioning position When in the disengaged position, the engaging portion 62 approaches the first end surface 915 and contacts the engaging portion 61 . When in the disengaged position, the engaging portion 62 is relatively far away from the engaging portion 61 .

The following is an overview of how to use the chair, and then a detailed description of the actions and principles of operation of each component during use.

When the user wants to adjust the position of the seat back unit 4 relative to the base column unit 2 along the first axis When the engaging portion 61 is in the disengaged position, the connection module 9 can rotate relative to the first joint plate 7 around the first axis L1, thereby driving the seat back unit 4 along the first axis L1. An axis direction X moves relative to the base column unit 2 . When the seat back unit 4 reaches a predetermined position, the clamping portion 62 is again operated to be in the positioning position relative to the inserting portion 61 along the first axis L1, so that the connecting mold can be The group 9 is positioned non-rotatably relative to the first joint plate 7 , thereby positioning the seat back unit 4 relative to the base column unit 2 along the first axis X.

Next, the following describes in detail the actions of each component when the locking portion 62 moves relative to the insertion portion 61 along the first axis L1 to further illustrate how the connection module 9 can move relative to the insertion portion 61 . The first joint plate 7 rotates around the first axis L1 or generates an action principle of positioning.

When the user wants to fix the connection module 9 to a non-rotatable position relative to the first joint plate 7 , he needs to first apply force on the holding part 74 to drive the adjusting part 73 around the first joint plate 7 . The axis L1 rotates, and the adjustment part 73 moves along the first axis L1 toward the direction of the connection module 9 through the engagement of the internal thread 713 and the external thread 732 . During the aforementioned movement, the adjusting portion 73 can be forced against the abutment area 711 and the clamping portion 62. Since the first base portion 71 and the clamping portion 62 are made of plastic material, Therefore, when pressed by the adjusting portion 73, it will elastically deform and move toward the connection module 9 to reach the positioning position (see Figure 6). In the positioning position, the clamping portion 62 contacts and presses the inserting portion 61 to generate frictional resistance so that the connection module 9 is positioned non-rotatably relative to the first joint plate 7 .

When the user wants to enable the connection module 9 to rotate relative to the first joint plate 7 around the first axis L1, he or she needs to first apply force on the holding portion 74 to drive the adjusting portion 73. Rotate around the first axis L1 to release the engagement between the internal thread 713 and the external thread 732 so that the adjustment portion 73 moves along the first axis L1 away from the connection module 9 direction movement. As the adjusting portion 73 gradually moves away from the abutment area 711 , the abutment area 711 and the clamping portion 62 will return to their original shape by utilizing the material properties of the first base portion 71 and the clamping portion 62 . The original shape gradually moves away from the engaging portion 61 and reaches the disengaged position (see Figure 5). Since in the disengaged position, the clamping portion 62 is relatively far away and no longer presses the clamping portion 61 , the connection module 9 can rotate around the first joint plate 7 relative to the first joint plate 7 . Axis L1 rotates.

Referring to Figures 4, 7, and 8, the following will continue to describe the actions and operating principles of each component when the connection module 9 rotates around the first axis L1 relative to the base module 51.

When the user wants to operate the seat back unit 4 to move from the approaching position shown in Figure 7 to the far away position shown in Figure 8, the user needs to operate the connection module 9 relative to the The base module 51 rotates around the first axis L1 in a counterclockwise direction, thereby driving the seat back unit 4 connected to the end of the connection module 9 opposite to the base module 51 to gradually move away from the The base column unit 2.

In addition, since the first rotating part 961 is connected to the base module 51, the relative position between the first rotating shaft 96 and the base module 51 is fixed during the aforementioned rotation. The rotation process of the base member 91 and the first groove 94 will cause the first rotation shaft 96 to slide from the first approaching end 941 (see the solid line position in Figure 4) to the first far away end. 942 (see the imaginary line position in Figure 4), and since the connecting rod 98 is pivotally connected between the first rotating shaft 96 and the second rotating shaft 97, it will synchronously drive the second rotating shaft 97 around The second axis L2 rotates and slides from the second approaching end 951 (see the solid line position in Figure 4) to the second far away end 952 (see the imaginary line position in Figure 4), plus the chair The back unit 4 is connected to the second rotating part 971 and pivoted to the second pivot part 931 , so the back unit 4 will be driven by the second rotating shaft 97 relative to the connection module 9 Rotate so that the chair back unit 4 can be maintained at a suitable angle for leaning.

During the above-mentioned rotation and movement, the height of the seat back unit 4 relative to the seat cushion unit 3 along the third axis Z will also change accordingly. To this end, the height of the seat back unit 4 can be changed by operating the sliding seat 22 The base module 51 is driven to move up and down along the pillar 21 and positioned, so as to adjust the seat back unit 4 to a suitable height.

In this way, when the connection module 9 rotates relative to the base module 51 , the seat back unit 4 is driven relative to the base column unit 2 along the first axis X in the By moving between the approaching position and the far away position, the distance between the front edge of the chair cushion unit 3 and the chair back unit 4 can be adjusted, and the chair back unit 4 can be maintained in a suitable position during the movement. angle to accommodate users of different body shapes.

It should be noted that in this embodiment, when the connection module 9 rotates relative to the base module 51 around the first axis L1, the first rotating part 961 will drive the The second rotating part 971 rotates around the second axis L2 to drive the seat back unit 4 to rotate around the second axis L2 relative to the connection module 9. However, in other implementations, the The first rotating part 961 may not drive the second rotating part 971 to rotate around the second axis L2, as long as the seat back unit 4 is pivotally connected to the connection module 9 and can be operated to adjust the The angle of the seat back unit 4 relative to the connection module 9 can also achieve the same effect.

It is worth mentioning that in this embodiment, through the base member 91 , the first groove 94 , the second groove 95 and the connecting rod 98 , each first pivot portion is 921 together with the corresponding first rotating part 961, the corresponding second rotating part 971 and the corresponding second pivoting part 931 constitute the four-bar linkage mechanism, and each first rotating part 961 is connected with the corresponding second rotating part 921. The distance between the parts 971 is fixed. However, in other embodiments, the connection module 9 can also use other components and other combinations to form the four-bar linkage mechanism to achieve the same effect. Purpose.

It should be noted that in this embodiment, the clamping part 62 is pressed against the inserting part 61 by operation, so that the connection module 9 can be non-rotatable relative to the first joint plate 7 However, in other embodiments, the locking part 62 and the clamping part 61 can also be designed to lock into each other. In this way, as long as the locking part 62 contacts the clamping part 61 The card portion 61 can also achieve the same purpose.

In addition, in this embodiment, the clamping part 62 of the positioning unit 6 is provided on the first base part 71, and the first base part 71 and the clamping part 62 are made of plastic material, so the third When a base part 71 and the clamping part 62 are pressed by the adjusting part 73, they will elastically deform and press the clamping part 61. However, in other embodiments, the clamping part 62 may also can be disposed on the adjusting portion 73, and the first base portion 71 and the clamping portion 62 can be made of non-plastic materials, as long as the adjusting portion 73 can be operated to move away from or away from the first axis L along the first axis L. The same purpose can also be achieved by moving toward the connection module 9 so that the engaging portion 62 is away from or contacts the engaging portion 61 .

To sum up, when the connection module 9 rotates relative to the base module 51 , the seat back unit 4 is driven relative to the base column unit 2 along the first axis X. By moving between the approaching position and the far away position, the distance from the front edge of the chair cushion unit 3 to the chair back unit 4 can be adjusted, and then the seat back unit 4 can be adjusted relative to the connection module 9. By rotating, the chair back unit 4 can be adjusted to a suitable angle for leaning, so that it can be used by users of different body shapes, thus achieving the purpose of the present invention.

Claims (7)

1. The utility model provides a chair, contains base column unit, seat cushion unit, and back of the chair unit, seat cushion unit connect in base column unit, back of the chair unit set up in the top of seat cushion unit, its characterized in that: the chair also comprises an adjusting unit, the adjusting unit comprises a base module connected with the base column unit, a connecting module capable of rotating around a first axis and generating a connecting module which is connected with the base module in a positioning way, the chair back unit can rotate around a second axis parallel to the first axis and generating a connecting module which is connected with one end of the connecting module opposite to the base module in a positioning way, the connecting module is provided with a base piece, a first pivot and a second pivot which are respectively penetrated through the base piece along the first axis and the second axis, a first groove and a second groove which are formed on the base piece and respectively rotate around the first axis and the second axis, a first rotating shaft and a second rotating shaft which are respectively penetrated through the first groove and the second groove in a positioning way, and a connecting rod which is pivoted between the first rotating shaft and the second rotating shaft, the first pivot is provided with a base module pivoted with the first axis and the base module, a second pivot which is respectively pivoted with the first base piece, a second pivot which is exposed with the second rotating shaft, a second pivot which is pivoted with the second connecting rod which is pivoted with the second pivot part which is pivoted with the base piece, a second pivot which is exposed with the second rotating shaft, a first pivot which is pivoted with the second pivot, the second pivot which is pivoted with the base piece, the second pivot which is pivoted with the second pivot which is exposed with the second pivot, the first pivot, the second pivot which is pivoted with the second pivot, the first rotating part and the second rotating part are respectively connected with the base module and the chair back unit and can synchronously and respectively rotate around the first axis and the second axis, the connecting module can rotate around the first axis relative to the base module to enable the chair back unit to move between a approaching position and a separating position along the first axis relative to the base column unit, when the connecting module rotates around the first axis relative to the base module, the first rotating part can rotate around the first axis and synchronously drive the second rotating part to rotate around the second axis so as to drive the chair back unit to rotate around the second axis relative to the connecting module, and when the connecting module approaches to the approaching position, the chair back unit is relatively adjacent to the base column unit, and when the connecting module moves away from the separating position, the chair back unit is relatively away from the base column unit.

2. A chair according to claim 1, wherein: the first groove of the adjusting unit is arc-shaped and is provided with a first approaching end relatively close to the base column unit and a first far-away end opposite to the first approaching end and relatively far away from the base column unit, the first rotating shaft is positioned at the first approaching end when the chair back unit is in the approaching position, and the first rotating shaft is positioned at the first far-away end when the chair back unit is in the far-away position.

3. A chair according to claim 1, wherein: the second groove of the adjusting unit is arc-shaped and is provided with a second approaching end relatively close to the base column unit and a second distant end opposite to the second approaching end and relatively far away from the base column unit, the second rotating shaft is positioned at the second approaching end when the chair back unit is in the approaching position, and the second rotating shaft is positioned at the second distant end when the chair back unit is in the distant position.

4. A chair according to claim 1, wherein: the base member of adjustment unit has first board portion, along perpendicular first axial second axial with the second board portion that first board portion interval set up, and connect first board portion with encircle board portion between the second board portion, first board portion second board portion with encircle board portion and cooperate together and prescribe a limit to supply the chamber that the connecting rod stretches to establish, first recess and second recess form in first board portion and intercommunication the chamber.

5. The chair according to claim 4, wherein: the connecting module of the adjusting unit is also provided with a first guide groove and a second guide groove, and the first guide groove and the second guide groove are formed on the second plate part and respectively correspond to the first groove and the second groove and are respectively provided for the first rotating shaft and the second rotating shaft to be slidably arranged.

6. The chair according to claim 4, wherein: the base module of the adjusting unit is provided with a first joint plate and a second joint plate which are arranged at intervals along the first axis, the first plate part is provided with a first end face opposite to the first joint plate, the chair further comprises a positioning unit, the positioning unit comprises a clamping part which is arranged on the first end face and surrounds the first axis, and a clamping part which is arranged on the first joint plate and is in concave-convex complementation with the clamping part, the clamping part can be operated to move along the first axis between a positioning position and a disengaging position relative to the clamping part, in the positioning position, the clamping part approaches the first end face and contacts the clamping part, the connecting module is positioned relative to the first joint plate in a non-rotatable mode, in the disengaging position, the clamping part is relatively far away from the clamping part, and the connecting module can rotate relative to the first plate around the first axis.

7. A chair according to claim 1, wherein: the base column unit comprises a column extending upwards and a sliding seat connected between the column and the base module and capable of being operated to drive the base module to move up and down along the column and generate positioning.