CHAIR FRAME AND MULTIFUNCTIONAL CHAIR

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Chinese patent application No. 202411259638.7, filed on Sep. 9, 2024, and titled “CHAIR FRAME AND MULTIFUNCTIONAL CHAIR” the content of which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

The present disclosure relates to the field of chair technology, in particular, to a chair frame and a multifunctional chair.

BACKGROUND

A multifunctional seat may be provided in at least three usage states including a sitting state, a leisure state, and a lying state, the sitting state, the leisure state, and the reclined state being for the user to sit down, to relax with the legs up, and to recline for rest, respectively. When the user intends to recline and rest, a leg assembly of the multifunctional chair is firstly extended to switch the multifunctional chair from the sitting state to the leisure state, and then tilts back a backrest assembly of the multifunctional chair to switch the multifunctional chair from the leisure state to the lying state. At the end of the rest period, the backrest assembly of the multifunctional chair is first reset to an upright position to return the multifunctional chair to the leisure state, then the leg assembly is retracted to switch the multifunctional chair from the leisure state to the sitting state, so that the user can get up and leave the multifunctional chair.

However, some multifunctional chairs in related art suffer from a disorganized state change. When returning from the lying state to the sitting state, the leg assembly may retract before the backrest assembly resets to an upright position, and the multifunctional chair cannot switch from the lying state to the sitting state as intended in the design of the product.

SUMMARY

In view of above, a chair frame and a multifunctional chair capable of being properly and orderly switched from a lying state to a sitting state, so as to overcome a problem of a disorganized state change of the chair frame.

A chair frame of the present disclosure includes a frame body assembly, a hip assembly, a backrest assembly, a linkage assembly, a leg assembly, a retracting and extending assembly, a leg assisting assembly and a restoring elastic member. The frame body assembly is provided with a retracting and extending actuator; the backrest assembly is rotatably connected to the frame body assembly and the hip assembly; a first connecting rod mechanism is defined by the linkage assembly, the hip assembly and the backrest assembly, and a second connecting rod mechanism is defined by the linkage assembly, the frame body assembly and the backrest assembly; the leg assembly is rotatably disposed on the hip assembly and connected to the retracting and extending actuator; the retracting and extending assembly is disposed on the hip assembly and movable relative to the hip assembly, the retracting and extending assembly includes a retracting and extending end and a driven end, and the retracting and extending end is connected to the leg assembly; when the retracting and extending end is driven to move forward by the leg assembly, the driven end is correspondingly driven to move backward, and when the retracting and extending end is driven to move backward by the leg assembly, the driven end is correspondingly driven to move forward; the driven end is connected to the frame body assembly via the leg assisting assembly, the leg assisting assembly is capable of being extended while the driven end moves forward, and being shorten while the driven end moves backward; and the restoring elastic member includes an assembling end connected to the frame body assembly and a restoring end connected to the hip assembly and/or the backrest assembly.

Compared with the related art, the chair frame in the present disclosure can be properly and orderly switched from a lying state to a leisure state, then switched from the leisure state to the lying state. In addition, it is ensured that when the chair frame is switched from the lying state to the sitting state, the backrest assembly is firstly reset. After the chair frame is switched to the leisure state and the backrest assembly is in an upright position, the leg assembly is retracted. Switching of the states of the chair frame adapts to process that a human body switches from a lying state to a sitting state, and the human body first erects the upper body and then bends the leg joints in order to get up and out of the chair.

In some embodiments, when the leg assembly is extended and the backrest assembly is reclined backward, the leg assisting assembly is in a first extending state, the restoring elastic member having a potential energy is capable of driving the backrest assembly to move forward to an upright position; when the leg assembly is extended and the backrest assembly is in the upright position, the restoring elastic member is retracted, and the leg assisting assembly is in a retracting state; when the leg assisting is retracted and the backrest assembly is in the upright position, the restoring elastic member is retracted, and the leg assisting assembly is in a second extending state.

In some embodiments, the linkage assembly includes a sharing connecting rod, the sharing connecting rod is located between the hip assembly and the frame body assembly.

In some embodiments, the linkage further includes a second connecting rod and a third connecting rod, both ends of the second connecting rod are pivotally connected to the hip assembly and the sharing connecting rod, respectively, and both ends of the third connecting rod are pivotally connected to the frame body assembly and the sharing connecting rod, respectively.

In some embodiments, the frame body assembly includes a backrest pedestal, the backrest assembly includes a pivoting portion, a backrest portion and a connecting rod portion, the pivoting portion is disposed between the backrest portion and the connecting rod portion and is pivotally connected to the backrest pedestal, a middle part of the connecting rod portion is pivotally connected to the hip assembly, and a rear end of the rod portion is pivotally connected to the sharing connecting rod.

In some embodiments, the retracting and extending assembly includes a retracting and extending rocking rod and a retracting and extending connecting rod, a middle part of the retracting and extending rocking rod is pivotally connected to the hip assembly, one end of the retracting and extending rocking rod is pivotally connected to the retracting and extending connecting rod, the other end of the retracting and extending rocking rod is regarded as the driven end, and an end of the retracting and extending connecting rod away from the retracting and extending rocking rod is regarded as the retracting and extending end.

In some embodiments, the retracting and extending rocking rod includes a swinging pivoting portion, a linkage pivoting portion and a driven pivoting portion, the swinging pivoting portion is located between the linkage pivoting portion and the driven pivoting portion and is pivotally connected to the hip assembly, the retracting and extending connecting rod is pivotally connected to the linkage pivoting portion, and the leg assisting assembly is pivotally connected to the driven pivoting portion, a length of the retracting and extending connecting rod is greater than a distance between the linkage pivoting portion and the swinging pivoting portion; and/or, the distance between the linkage pivoting portion and the swinging pivoting portion is less than a distance between the driven pivoting portion and the swinging pivoting portion.

In some embodiments, the frame body assembly includes an assembling lateral plate extending along a forward and backward direction, the leg assisting assembly includes a leg assisting spring, one end of the leg assisting spring is connected to the driven end, and the other end of the leg assisting spring is connected to a rear end of the assembling lateral plate.

In some embodiments, the leg assembly includes a first rod, a second rod, a third rod, a fourth rod, a fifth rod, a sixth rod and a seventh rod; the first rod and the second rod are pivotally connected to the hip assembly; the third rod is pivotally connected to the first rod and the second rod; the fourth rod is pivotally connected to the second rod; the fifth rod is pivotally connected to the third rod and the fourth rod; the sixth rod is pivotally connected to the fifth rod; the seventh rod is pivotally connected to the third rod and the sixth rod; and the retracting and extending end is pivotally connected to the first rod or the second rod.

In some embodiments, the retracting and extending assembly includes a retracting and extending rocking rod and a retracting and extending connecting rod, a middle part of the retracting and extending rocking rod is pivotally connected to the hip assembly, one end of the retracting and extending rocking rod is pivotally connected to the retracting and extending connecting rod, the other end of the retracting and extending rocking rod is regarded as the driven end, an end of the retracting and extending connecting rod away from the retracting and extending rocking rod is regarded as the retracting and extending end and is pivotally connected to the second rod; and a distance from a hinge joint of the second rod and the hip join to the retracting and extending end is less than a length of the retracting and extending connecting rod.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a structural schematic diagram of a chair frame in a lying state in some embodiments of the present disclosure.

FIG. 2 is a side view of a part of structures of a chair frame in some embodiments of the present disclosure.

FIG. 3 is a side view of a chair frame in a sitting state in some embodiments of the present disclosure.

FIG. 4 is a side view of a chair frame in a leisure state in some embodiments of the present disclosure.

FIG. 5 is a side view of a chair frame in a lying state in some embodiments of the present disclosure.

FIG. 6 is a schematic diagram showing a connection relationship of a chair frame in some embodiments of the present disclosure.

In the figures,

• • 10 represents a frame body assembly; 11 represents an assembling lateral plate; 111 represents a third spring assembling point; 112 represents a connecting rod restricting portion; 12 represents a backrest pedestal; 121 represents a fourth spring assembling point; 122 represents a backrest restricting portion; 13 represents a first connecting pipe; 14 represents a spring assembling pedestal; 15 represents a motor assembling pedestal;
  • 20 represents a hip assembly; 21 represents a hip-leg supporting frame; 211 represents a first spring assembling point; 212 represents a second spring assembling point; 213 represents a leg restricting portion; 22 represents a rocking rod pedestal;
  • 30 represents a backrest assembly; 31 represents a pivoting portion; 32 represents a backrest portion; 33 represents a connecting rod portion; 34 represents a third connecting pipe;
  • 40 represents a linkage assembly; 41 represents a sharing connecting rod; 42 represents a second connecting rod; 43 represents a third connecting rod;
  • 50 represents a leg assembly; 501 represents a second connecting pipe; 51 represents a first rod; 52 represents a second rod; 53 represents a third rod; 54 represents a fourth rod; 55 represents a fifth rod; 56 represents a sixth rod; 57 represents a seventh rod;
  • 60 represents a retracting and extending assembly; 61 represents a retracting and extending rocking rod; 611 represents a swinging pivoting portion; 612 represents a driven end; 613 represents a linkage pivoting portion; 62 represents a retracting and extending connecting rod; 621 represents a retracting and extending end;
  • 70 represents a leg assisting assembly;
  • 80 represents a restoring elastic member; 81 represents a first restoring spring; 82 represents a second restoring spring;
  • 90 represents a retracting and extending actuator; and 91 represents a motor body; and 92 represents a retracting and extending rod of the motor.

DETAILED DESCRIPTION

The technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, but not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by a person of ordinary skill in the art without making creative labor fall within the scope of protection of the present disclosure.

Unless otherwise defined, all technical and scientific terms used in the specification of the present disclosure have the same meaning as commonly understood by those skilled in the art to which the present disclosure belongs. Terms used in the specification of the present disclosure are used only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. The term “and/or” as used in the specification of the present disclosure includes any and all combinations of one or more of the relevant listed items.

A chair frame and a multifunctional chair are provided in the present disclosure. The multifunctional chair includes a chair frame and a soft material coated on the chair frame. The soft material includes a seat cushion, a leg rest, back cushion, and the like. The chair frame has at least three using states including a sitting state, a leisure state and a lying state. The sitting state of the frame chair allows the user to sit with legs bent and feet on the ground and torso straight, the leisure state of the frame chair allows the user to sit with legs extended and feet off the ground and torso straight, and the lying state of the frame chair allows the user to lie down with legs extended and feet off the ground and torso lying down.

Referring to FIG. 1, FIG. 2 and FIG. 6, the chair frame of the present disclosure includes a frame body assembly 10, a hip assembly 20, a backrest assembly 30, a linkage assembly, a leg assembly 50, a restoring elastic member and a retracting and extending actuator 90. The frame body assembly 10 is used as an installation foundation of the hip assembly 20, the backrest assembly 30 and the retracting and extending actuator 90. The hip assembly 20 includes a hip-leg supporting frame 21 and a rocking rod pedestal 22 fixed to each other. The hip-leg supporting frame 21 is configured for supporting a hip and a thigh of the human body. The backrest assembly 30 is configured for supporting a waist and a back of the human body. A first connecting rod mechanism is defined by the linkage assembly, the hip assembly 20 and the backrest assembly 30, and a second connecting rod mechanism is defined by the linkage assembly, the frame body assembly 10 and the backrest assembly 30. The first connecting rod mechanism and the second connecting rod mechanism are connected in series, and the first connecting rod mechanism and the second connecting rod mechanism can move synergistically, so that when the chair frame is switched between the lying state and the leisure state, the hip assembly 20 and the backrest assembly 30 can simultaneously move relative to the frame body assembly 10, the leg assembly 50 can be rotatably connected to the hip-leg supporting frame 21 and connected to the retracting and extending actuator 90. The restoring elastic member includes an assembling end and a restoring end, the assembling end is connected to the frame body assembly 10, and the restoring end is connected to at least one of the hip assembly 20 or the backrest assembly 30. The retracting and extending actuator 90 is configured for providing a power for the chair frame to act and be switched between different states. The soft material includes a seat cushion disposed on the hip-leg supporting frame 21.

FIG. 3, FIG. 4, and FIG. 5 show structures of the chair frame in a sitting state, a leisure state and a lying state, respectively. When the chair frame is in the sitting state, the leg assembly 50 is retracted and accommodated at a side of the hip assembly 20 adjacent to the ground, and the backrest assembly 30 is in an upright position. When the chair frame is in the leisure state, the leg assembly 50 is rotated relative to the hip assembly 20 and switched to an extending state. At this time, the leg assembly 50 is suspended relative to the ground and the backrest assembly 30 is in the upright position. When the chair frame is in the lying state, the leg assembly 50 is kept in the extending state and suspended relative to the ground, the hip assembly 20 moves forward relative to the frame body assembly 10, a front end of the hip-leg supporting frame 21 away from the backrest assembly 30 is lifted relative to a rear end of the hip-leg supporting frame 21 adjacent to the backrest assembly 30, and the backrest assembly 30 is rotated relative to the hip assembly 20 to a reclining state. When the chair frame is switched from the sitting state to the leisure state and further to the lying state, a power of the retracting and extending actuator 90 firstly acts on the leg assembly 50 to switch the chair frame to the leisure state, and then acts on the first connecting rod mechanism and the second connecting rod mechanism. When the chair frame is switched from the lying state to the leisure state and further to the sitting state, the power of the retracting and extending actuator 90 firstly acts on the first connecting rod mechanism and the second connecting rod mechanism to switch the chair frame to the leisure state, and the acts on the leg assembly 50.

In order to ensure that the chair frame is smoothly switched from the lying state shown in FIG. 5 to the leisure state shown in FIG. 4, and then switched from the leisure state shown in FIG. 4 to the sitting state shown in FIG. 3, the chair frame of the present disclosure further includes a retracting and extending assembly 60 and a leg assisting assembly 70. The retracting and extending assembly 60is disposed on the hip assembly 20 and movable relative to the hip assembly 20. The retracting and extending assembly 60 includes a retracting and extending end 621 and a driven end 612, and the retracting and extending end 621 is connected to the leg assembly 50. The driven end 612 is connected to one end of the leg assisting assembly 70, the other end of the leg assisting assembly 70 is connected to the frame body assembly 10. The leg assisting assembly 70 includes a leg assisting spring. Both ends of the leg assisting spring are regarded as both ends of the leg assisting assembly 70. When the leg assembly 50 is switched from the retracting and accommodating state to the extending state under the action of the retracting and extending actuator 90, the retracting and extending end 621 is driven to move forward by the leg assembly 50, during which the driven end 612 is correspondingly driven to move backward and make leg assisting assembly 70 be shortened. When the leg assembly 50 is switched from the extending state to the retracting and accommodating state under the action of the retracting and extending actuator 90, the retracting and extending end 621 is driven to move backward by the leg assembly 50, and the driven end 612 is correspondingly driven to move forward and stretches the leg assisting assembly 70.

It should be noted that the orientation terms of “front” and “rear” in the present embodiment are based on the user's perception of orientation when sitting in the chair frame/functional chair. The leg assembly 50 in the extending state is in front of the user, the backrest assembly 30 is located behind the user. That the retracting and extending end 621 moves forward indicates that the retracting and extending end 621 moves to a front direction as the user perceives when the user seats on the chair frame. In other words, in FIG. 2 to FIG. 6, when the retracting and extending end 621 moves forward, the retracting and extending end 621 moves towards the left side of the figure. That the retracting and extending end 621 moves backward indicates that the retracting and extending end 621 moves to a rear direction as the user perceives when the user seats on the chair frame. In other words, in FIG. 2 to FIG. 6, when the retracting and extending end 621 moves backward, the retracting and extending end 621 moves towards the right side of the figure. Detail descriptions of orientations and moving directions of other components are not repeated herein.

Referring to FIG. 1, FIG. 5 and FIG. 6, the linkage assembly includes a sharing connecting rod 41, a second connecting rod 42 and a third connecting rod 43. The sharing connecting rod 41 is located between hip assembly 20 and frame body assembly 10. Both ends of the second connecting rod 42 are pivotally connected to the hip assembly 20 and the sharing connecting rod 41. Both ends of the third connecting rod 43 are pivotally connected to the frame body assembly 10 and the sharing connecting rod 41. The frame body assembly 10 includes an assembling lateral plate 11 and a backrest pedestal 12. The backrest pedestal 12 is fixed to a rear end of the assembling lateral plate 11. The backrest assembly 30 includes a pivoting portion 31, a backrest portion 32 and a connecting rod portion 33. The pivoting portion 31 is located between backrest portion 32 and connecting rod portion 33 and is pivotally connected to the backrest pedestal 12. One end of the connecting rod portion 33 is connected to the pivoting portion 31, the other end of the connecting rod portion 33 is pivotally connected to the sharing connecting rod 41. A middle part of the connecting rod portion 33 located between both ends of the connecting rod portion 33 is pivotally connected to a rear end of the hip-leg supporting frame 21. A four rod mechanism defined by the hip assembly 20, the second connecting rod 42, the sharing connecting rod 41 and the backrest assembly 30 is regarded as the first connecting rod mechanism. A four rod mechanism defined by the third connecting rod 43, the sharing connecting rod 41, the backrest assembly 30 and the frame body assembly 10 is regarded as the second connecting rod mechanism. The soft material includes a back cushion disposed on the backrest portion 32.

Referring to FIG. 6, a hinge joint of the second connecting rod 42 and the hip-leg supporting frame 21 is defined as point N, a hinge joint of the second connecting rod 42 and the sharing connecting rod 41 is defined as point O, a hinge joint of the third connecting rod 43 and the sharing connecting rod 41 is defined as point P, a hinge joint of the third connecting rod 43 and the assembling lateral plate 11 is defined as point Q, a hinge joint of the sharing connecting rod 41 and the rear end of the connecting rod portion 33 is defined as point R, a hinge joint of the middle part of the connecting rod portion 33 and the hip-leg supporting frame 21 is defined as point S, and a hinge joint of the pivoting portion 31 and the backrest pedestal 12 is defined as point T. Four hinge joints of the first connecting rod mechanism are point N, point O, point R and point S, respectively; and four hinge joints of the second connecting rod mechanism are point P, point Q, point T and point R, respectively. Both the first connecting rod mechanism and the second connecting rod mechanism include the connecting rod portion 33 of the backrest assembly 30 and the sharing connecting rod 41. In this way, both the first connecting rod mechanism and the second connecting rod mechanism can simultaneously act or deform. When the chair frame is in the leisure state, the leg assembly 50 is sufficiently extended. If the retracting and extending actuator 90 continue to generate a driving force, the leg assembly 50 will remain fixed relative to the hip assembly 20. Then, the hip assembly 20 moves forward relative to the frame body assembly 10, while the front end of the hip assembly 20 being lifted up. The backrest assembly 30 is driven by the sharing connecting rod 41 to recline relative to the backrest pedestal 12, the backrest portion 32 is swinged and reclined, and the chair frame is finally switched to the lying state.

Referring to FIG. 1, FIG. 4 and FIG. 5, the restoring elastic member includes a first restoring spring 81 and a second restoring spring 82. The hip-leg supporting frame 21includes a first spring assembling point 211 and a second spring assembling point 212. The assembling lateral plate 11 includes a third spring assembling point 111. The backrest pedestal 12includes a fourth spring assembling point 121. Both ends of the first restoring spring 81 are connected to the first spring assembling point 211 and the third spring assembling point 111, respectively. Both ends of the second restoring spring 82 are connected to the second spring assembling point 212 and the fourth spring assembling point 121, respectively. The first restoring spring 81 and the second restoring spring 82 play the same role. Both the first restoring spring 81 and the second restoring spring 82 are configured to apply a tensile force to the hip assembly 20, so that the hip assembly 20 has a tendency to move backward relative to the frame body assembly 10. When the chair frame is switched from the lying state in FIG. 5 to the leisure state in FIG. 4, in one aspect, the hip assembly 20 move backward relative to the frame body assembly 10, in the other aspect, the front end of the hip-leg supporting frame 21 is lowered. In addition, the sharing connecting rod 41 moves backward relative to the frame body assembly 10, so as to drive the backrest assembly 30 to recover to the upright position. In this way, the tensile force of the first restoring spring 81 and the second restoring spring 82 applied on the hip assembly 20 can facilitate the hip assembly 20 to move backward relative to the frame body assembly 10, so as to facilitate switching of the chair frame from the lying state to the leisure state and ensure that the backrest assembly 30 is firstly restored.

In some embodiments, the restoring elastic member can be provided with the second restoring spring 82 without the first restoring spring 81; optionally, the restoring elastic member can be provided with the first restoring spring 81 without the second restoring spring 82.

Referring to FIG. 1, FIG. 2, FIG. 4 and FIG. 5, in some embodiments, the leg assembly 50 includes a first rod 51, a second rod 52, a third rod 53, a fourth rod 54, a fifth rod 55, a sixth rod 56 and a seventh rod 57. The first rod 51 and the second rod 52 are pivotally connected to the front end of the hip-leg supporting frame 21, the third rod 53 is pivotally connected to the first rod 51 and the second rod 52, the fourth rod 54 is pivotally connected to the second rod 52, the fifth rod 55 is pivotally connected to the third rod 53 and the fourth rod 54, the sixth rod 56 is pivotally connected to the fifth rod 55, the seventh rod 57 is pivotally connected to the third rod 53 the sixth rod 56, and the retracting and extending end 621 of the retracting and extending assembly 60 is pivotally connected to the first rod 51 or the second rod 52. A four-connecting rod mechanism is defined by the hip-leg supporting frame 21, the first rod 51, the second rod 52 and the third rod 53, and a shape defined by connecting lines of four hinge joints of the four-connecting rod mechanism is similar to a parallelogram. Referring to FIG. 6, a hinge joint of the first rod 51 and the hip-leg supporting frame 21 is defined as point A, a hinge joint of the second rod 52 and the hip-leg supporting frame 21 is defined as point B, a hinge joint of the second rod 52 and the fourth rod 54 is defined as point C, a hinge joint of the fourth rod 54 and the fifth rod 55 is defined as point D, a hinge joint of the first rod 51 and the third rod 53 is defined as point E, a hinge joint (not shown) of the third rod 53 and the second rod 52 is adjacent to point C but not overlap with point C, a hinge joint of the fifth rod 55 and the third rod 53 is defined as point F, a hinge joint of the sixth rod 56 and the fifth rod 55 is defined as point G, a hinge joint of the seventh rod 57 and the sixth rod 56 is defined as point H, and a hinge joint of the seventh rod 57 and the third rod 53 is defined as point I. The soft material includes a leg rest disposed on the seventh rod 57.

Referring to FIG. 1 to FIG. 6, in some embodiments, the retracting and extending end 621 is pivotally connected to the second rod 52, and a hinge joint of the retracting and extending end 621 and the second rod 52 is defined as point J.

Referring to FIG. 1, frame body assembly 10 further includes a first connecting pipe 13, which is located a rear end of the assembling lateral plate 11 and fixed to the backrest pedestal 12. The first connecting pipe 13 is provided with a spring assembling pedestal 14 and a motor assembling pedestal 15. An end of the leg assisting spring away from the driven end 612 is pivotally connected to the spring assembling pedestal 14. The leg assembly 50 further includes a second connecting pipe 501 fixed to the first rod 51. The backrest assembly 30 further includes a third connecting pipe 34 fixed to the backrest portion 32. The retracting and extending actuator 90 is a linear actuator, which includes a motor body 91 and a retracting and extending rod of the motor 92. The motor body 91 is rotatably connected to the motor assembling pedestal 15. One end of the retracting and extending rod of the motor 92 is located in the motor body 91, and the other end of the retracting and extending rod of the motor 92 extends out of the motor body 91 and is pivotally connected to the second connecting pipe 501. The linear actuator can control a length of the retracting and extending rod of the motor 92 extending out of the motor body 91. When the user switches the chair frame from the sitting state to the lying state, the length of the retracting and extending rod of the motor 92 extending out of the motor body 91 increases, the retracting and extending rod of the motor 92 applies a pushing force to the first rod 51 via the second connecting pipe 501, so that the leg assembly 50 is driven to gradually extend from the retracting and accommodating state. After the leg assembly 50 is sufficiently extended to the leisure state, the length of the retracting and extending rod of the motor 92 extending out of the motor body 91 continuously increases, the retracting and extending rod of the motor 92 applies the pushing force to the leg assembly 50 and the hip assembly 20 via the second connecting pipe 501, so that the leg assembly 50 is driven to move forward together with the hip assembly 20. When the user tries to switch the chair frame from the lying state to the sitting state, the length of the retracting and extending rod of the motor 92 extending out of the motor body 91 is shortened, the retracting and extending rod of the motor 92 applies a pulling force to the leg assembly 50 and the hip assembly 20 via the second connecting pipe 501, so as to drive the leg assembly 50 and the hip assembly 20 to move together and switch the chair frame to the leisure state. In a process of switching the chair frame from the lying state to the leisure state, the leg assembly 50 is kept extended, the leg assembly 50 is fixed to relative to the hip assembly 20, then the length of the retracting and extending rod of the motor 92 extending out of the motor body 91 is continuously shortened, the retracting and extending rod of the motor 92 applies the pulling force to the leg assembly 50 via the second connecting pipe 501. Then the hip assembly 20 is fixed relative to the frame body assembly 10, the leg assembly 50 is gradually retracted and accommodated from the extending state, and the chair frame is finally switched to the sitting state.

In some embodiments, the retracting and extending assembly 60 includes a retracting and extending rocking rod 61 and a retracting and extending connecting rod 62. One end of the retracting and extending rocking rod 61 is pivotally connected to retracting and extending connecting rod 62, the other end of the retracting and extending rocking rod 61 is regarded as the driven end 612 and connected to one end of the leg assisting assembly 70. A middle part of the retracting and extending rocking rod 61 located between both ends of the retracting and extending rocking rod 61 is pivotally connected to the rocking rod pedestal 22, an end of the retracting and extending connecting rod 62 away from the retracting and extending rocking rod 61 is regarded as the retracting and extending end 621 and is pivotally connected to the leg assembly 50. Referring to FIG. 1, FIG. 2, FIG. 5 and FIG. 6, the retracting and extending rocking rod 61 includes a linkage pivoting portion 613 disposed at one end of the retracting and extending rocking rod 61, a driven pivoting portion disposed at the other end of the retracting and extending rocking rod 61, and a swinging pivoting portion 611 located at the middle part of the retracting and extending rocking rod 61. A hinge joint of the swinging pivoting portion 611 and the rocking rod pedestal 22 is defined as point L, and a hinge joint of the linkage pivoting portion 613 and the retracting and extending connecting rod 62 is defined as point K. The driven pivoting portion is located at the driven end 612, a hinge joint of the end of the leg assisting assembly 70 and the driven pivoting portion is defined as point M, and a hinge joint of the retracting and extending end 621and the leg assembly 50 is regarded as point J. A length of the retracting and extending connecting rod 62 is greater than a distance between point K to point L, and the length of the retracting and extending connecting rod 62 is greater than a distance between point B to point J, the distance between point K to point L is less than a distance between point M to point L.

In this way, when the leg assembly 50 is rotated relative to the hip assembly 20, the retracting and extending connecting rod 62 basically moves along a length direction of the hip-leg supporting frame 21, the retracting and extending connecting rod 62 is approximately parallel to the hip-leg supporting frame 21. When the leg assembly 50 is switched from the retracting and accommodating state to the extending state to allow the chair frame be switched from the sitting state to the leisure state, the retracting and extending connecting rod 62 is driven by the leg assembly 50 to move forward relative to the hip-leg supporting frame 21. Thus, the retracting and extending end 621 moves forward, the retracting and extending rocking rod 61 is driven by the retracting and extending connecting rod 62 to rotate relative to the rocking rod pedestal 22, the driven end 612 is driven by the retracting and extending connecting rod 62 to move backward. In this way, in a process that the chair frame is switched from the lying state to the leisure state, the leg assisting spring is shortened along with moving backward of the driven end 612, a part of elastic potential energy of the leg assisting spring is released to assist extending of the leg assembly 50. When the user tries to continuously switch the chair frame to the lying state, the leg assembly 50 is kept fixed relative to the hip assembly 20 and sufficiently extended, the leg assembly 50 and the hip assembly 20 moves forward as a whole relative to the frame body assembly 10, and the leg assembly 50 is lifted up. In this period, both the retracting and extending connecting rod 62 and the retracting and extending rocking rod 61 are fixed relative to the hip assembly 20, the leg assisting spring is further stretched along with moving forward of the retracting and extending assembly 60. In this way, when the chair frame is switched from the sitting state to the leisure state, and switched from the leisure state to the lying state, a length of the leg assisting spring is firstly shortened and then elongated by the driven end 612, the retracting and extending connecting rod 62 is firstly moved forward relative to the hip assembly 20 and then fixed relative to the hip assembly 20, and the retracting and extending rocking rod 61 is firstly rotated relative to the hip assembly 20 and then fixed relative to the hip assembly 20.

For the chair frame in related art, when the user tries to switch the chair frame from the lying state to the sitting state, the frame will suffer from a problem of a disorganized state change of the chair frame. The state change of the chair frame includes two situations: 1) the backrest assembly 30 is firstly restored to an upright position, and then the leg assembly 50 is restored to the retracting and accommodating state from the extending state; and 2) the leg assembly 50 is firstly restored to the retracting and accommodating state from the extending state, and then the backrest assembly 30 is restored to the upright position. In most of the conditions, the chair frame in related art does not have a certain order of state change, and both of the two situations may occur.

In the present disclosure, the chair frame has a certain order of state change. When the user switch the chair frame of the present disclosure from the lying state to the sitting state, the chair frame of the present disclosure can strictly follow the first situation of state change described above. That is, the backrest assembly 30 is firstly restored to an upright position and the chair frame is switched to the leisure state, and then the leg assembly 50 is restored to the retracting and accommodating state from the extending state, and finally the chair frame is switched to the sitting state. Principles of the present invention having a defined sequence of state change is described below in conjunction with FIG. 3, FIG. 4 and FIG. 5.

On account of the structure of the chair frame of the present disclosure, referring to FIG. 3 and FIG. 5, in a hypothetic situation A: in a process that the chair frame in the lying state is switched to the sitting state, the leg assembly 50 is firstly retracted and accommodated, the retracting and extending assembly 60 is firstly deformed under the action of a pulling force of the retracting and extending actuator 90 applied on the leg assembly 50. Deformation of the retracting and extending assembly 60 includes: moving backward of the retracting and extending connecting rod 62 relative to the hip-leg supporting frame 21, and rotation of the retracting and extending rocking rod 61relative to the rocking rod pedestal 22. If the retracting and extending connecting rod 62 moves backward relative to the hip-leg supporting frame 21, the driven end 612 is driven to move forward relative to the hip-leg supporting frame 21, so as to make the leg assisting spring be elongated. It is obvious that elongation of the leg assisting spring will cost a part of the power of the retracting and extending actuator 90.

In a hypothetic situation B: in a process that the chair frame in the lying state is switched to the sitting state, the backrest assembly 30 is firstly switched to an upright direction, the hip assembly 20 is driven to move backward relative to the frame body assembly 10 under a pulling force of the retracting and extending actuator 90 applied on the leg assembly 50. At this time, the elastic potential of the first restoring spring 81 and the second restoring spring 82 can be rightly released to help the hip assembly 20 to move backward relative to the frame body assembly 10. In this period, the leg assisting spring will not be elongated. In other words, the retracting and extending actuator 90 does not need extra power to overcome an elastic force of the elongated leg assisting spring.

It can be concluded that in comparison to the hypothetic situation A, the hypothetic situation B is more consistent with the principle of minimum energy consumption than the hypothetic situation A, as described above. That is, an energy consumption of restoring the backrest assembly 30 before the leg assembly 50 is smaller than an energy consumption of restoring the leg assembly 50 before the backrest assembly 30. For the chair frame of the present disclosure, if the leg assembly 50 is forced to restore before the backrest assembly 30, the leg assisting spring should be elongated by the driven end 612, while the first restoring spring 81 and the second restoring spring 82 being controlled not to retract, so as to ensure that the hip assembly 20 will not move backward, thereby ensuring that the sharing connecting rod 41 will not drive the backrest assembly 30 to the upright position before the leg assembly 50 is retracted and accommodated. In this way, an extra power take-off is required by the retracting and extending actuator 90 to maintain shapes of the first restoring spring 81 and the second restoring spring 82. In this way, for the chair frame of the present disclosure, it is inevitable that the backrest assembly 30 restores before the leg assembly 50. After the chair frame is switched to the leisure state, it is only necessary for the retracting and extending actuator 90 to continuously apply the puling force to the leg assembly 50 and apply the pulling force on the retracting and extending assembly 60 via the leg assembly, so as to make the driven end 612 move forward and elongate the leg assisting spring. The retracting and extending end 621 will move backward along with the driven end 612 moving forward, so that the leg assembly 50 is retracted and accommodated.

Referring to FIG. 2 and FIG. 6, in order to ensure that the retracting and extending connecting rod 62 moves along a forward and backward direction being similarly parallel to the hip-leg supporting frame 21, the rocking rod pedestal 22 protrudes out from a side of the hip-leg supporting frame 21 adjacent to the ground, a hinge joint point L of the rocking rod pedestal 22 and the retracting and extending rocking rod 61is located below the hip-leg supporting frame 21, and a four connecting rod mechanism defined by the retracting and extending connecting rod 62, the second rod 52, the hip assembly 20 and the retracting and extending rocking rod 61 is a concave quadrilateral from beginning to end. Four hinge joints of the four connecting rod mechanism defined by the retracting and extending connecting rod 62, the second rod 52, the hip assembly 20 and the retracting and extending rocking rod 61 are defined as point B, point J, point K and point L, respectively.

When the chair frame is switched from the leisure state to the lying state, the leg assisting spring is elongated by the driven end 612, elongation of the leg assisting spring is related to a structure of the retracting and extending rocking rod 61. Referring to FIG. 6, the greater a length ratio of a length of a connecting line from point L to point M to a length of a connecting line from point L to point K is, the greater the elongation of the leg assisting spring is. That is, it is only necessary for retracting and extending connecting rod 62 to move slightly along a length direction of the hip-leg supporting frame 21, the driven end 612 can be driven to move forward or backward by a large margin. The greater a length ratio of a length of a connecting line from point L to point M to a length of a connecting line from point L to point K is, it is more conductive to ensure that the backrest assembly 30 restored to the upright position before the leg assembly 50 is retracted and accommodated in the process that the chair frame is switched from the lying state to the sitting state.

Referring to FIG. 1, and FIG. 3 to FIG. 6, the hip assembly 20 further includes a leg restricting portion 213 fixed on the hip-leg supporting frame 21. The leg restricting portion 213 is located between point A and point B. The frame body assembly 10 further includes a connecting rod restricting portion 112 fixed on the assembling lateral plate 11, and a backrest restricting portion 122 fixed on the backrest pedestal 12. The leg restricting portion 213 is configured for abutting against the first rod 51 after the leg assembly 50 is retracted and accommodated, and abutting the second rod after the leg assembly 50 is extended. The connecting rod restricting portion 112 is configured for abutting against the third connecting rod 43 to limit deformation of the first connecting rod mechanism and deformation of the second connecting rod mechanism. The backrest restricting portion 122 is configured for abutting against the connecting rod portion 33 to limit the deformation of the first connecting rod mechanism and the deformation of the second connecting rod mechanism. When the chair frame is switched from the sitting state to the leisure state, the connecting rod restricting portion 112 abuts against the third connecting rod 43, backrest restricting portion 122 abuts against the connecting rod portion 33. The retracting and extending actuator 90 firstly drives the leg assembly 50 to gradually extend, the first rod 51 separates from the leg restricting portion 213 until the second rod 52 abuts against the leg restricting portion 213, so that the chair frame is switched to the leisure state. Then the leg assembly 50 is fixed relative to the hip assembly 20, the hip assembly 20 is driven by the retracting and extending actuator 90 to move forward and rise, so as to drive the first connecting rod mechanism and the second connecting rod mechanism to deform. Thus, the third connecting rod 43 is separated from the connecting rod restricting portion 112, and the connecting rod portion 33 is separated from the backrest restricting portion 122. In the process that the chair frame is switched from the lying state to the leisure state, the leg assembly 50 is fixed relative to the hip assembly 20, the hip assembly 20 is driven by the retracting and extending actuator 90 to move backward and decline, so as to drive the first connecting rod mechanism and the second connecting rod mechanism to deform until the third connecting rod 43 abuts against the connecting rod restricting portion 112 and the connecting rod portion 33 abuts against the backrest restricting portion 122. Then, the backrest assembly 30 and the hip assembly 20 are fixed relative to the frame body assembly 10, and the leg assembly 50 is driven by the retracting and extending actuator 90 to retract and accommodate to make the second rod 52 separate from the leg restricting portion 213 until the first rod 51 abuts against the leg restricting portion 213, so that the chair frame is switched to the sitting state.

In some embodiments, when the chair frame is in the lying state, the leg assisting assembly 70 is in the first extending state, the restoring elastic member has an elastic potential energy capable of driving the backrest assembly 30 to restore to the upright position, and the elastic potential energy of the restoring elastic member is the maximum at this time. When the chair frame is in the leisure state, the restoring elastic member is retracted relative to the lying state, and the leg assisting assembly 70 is in the retracting state. When the chair frame is in the sitting state, the restoring elastic member basically does not change relative to the restoring elastic member in the leisure state, and the leg assisting assembly 70 is in the second extending state. Referring to FIG. 3 to FIG. 5, the leg assisting assembly 70 includes a leg assisting spring. In the chair frame of FIG. 3, the leg assisting spring is in the second extending state. In the chair frame of FIG. 4, the leg assisting spring is in the retracting state. In the chair frame of FIG. 5, the leg assisting spring is in the first extending state. A length of the leg assisting spring in the second extending state is greater than a length of the leg assisting spring in the first extending state, and the length of the leg assisting spring in the first extending state is greater than a length of the leg assisting spring in the retracting state. In this way, in the sitting state, the leg assisting spring can accumulate more elastic potential energy, the leg assisting spring can apply a pulling force to the driven end 612, the driven end 612 has a tendency to move backward, so that the retracting and extending connecting rod 62 has a tendency to move forward. Under this tendency, the retracting and extending end 621 has a thrusting effect on the second rod 52, which facilitates extending of the leg assembly 50.

The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features are described in the embodiments. However, as long as there is no contradiction in the combination of these technical features, the combinations should be considered as in the scope of the present disclosure.

The above-described embodiments are only several implementations of the present disclosure, and the descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present disclosure. It should be understood by those of ordinary skill in the art that various modifications and improvements can be made without departing from the concept of the present disclosure, and all fall within the protection scope of the present disclosure. Therefore, the patent protection of the present disclosure shall be defined by the appended claims.