CN110123032B

CN110123032B - Liftable folding dining table and working method thereof

Info

Publication number: CN110123032B
Application number: CN201910524437.8A
Authority: CN
Inventors: 张丽萍; 何金理; 罗力维
Original assignee: Fuzhou University
Current assignee: Fuzhou University
Priority date: 2019-06-18
Filing date: 2019-06-18
Publication date: 2023-07-07
Anticipated expiration: 2039-06-18
Also published as: CN110123032A

Abstract

The invention relates to a liftable folding dining table and a working method thereof, wherein the liftable folding dining table comprises table legs and a table top plate, the table legs comprise lower table legs and upper table legs which are sleeved at the upper ends of the lower table legs along a sliding way, the lower table legs are connected with vertically arranged lifting screws in a threaded manner, and a power mechanism A for driving the lifting screws to rotate is arranged on the upper table legs; the desktop board comprises a fixed desktop board fixedly connected to the top of the upper desk leg and folding desktop boards arranged on two sides of the fixed desktop board, the folding desktop board comprises a primary folding desktop board and a secondary folding desktop board, the primary folding desktop board is positioned between the fixed desktop board and the secondary folding desktop board, the primary folding desktop board is hinged with the fixed desktop board through a hinge, and a folding telescopic lever mechanism driven by a power mechanism B is arranged between the secondary folding desktop board and the upper desk leg. The folding and lifting integrated desk has reasonable structural design and convenient operation, integrates folding and lifting, has the automatic telescopic function of a common telescopic desk, realizes folding and unfolding of the desk top twice, and has larger desk top area.

Description

Liftable folding dining table and working method thereof

Technical field:

the invention relates to a liftable folding dining table and a working method thereof.

The background technology is as follows:

with the improvement of modern living standard, people have great demands on functions and tastes of furniture. The use of furniture is not limited to the practical function, but more and higher requirements are put on the furniture, such as richness of furniture function use, convenience of use, attractive appearance and the like. The use requirements of people on furniture are mainly divided into the following aspects: the multifunctional portable multifunctional desk has the advantages of richer and more integrated use functions, simpler and more automatic use modes, more attractive and more humanized appearance design.

The main forms of the current folding dining table are as follows:

1. the folding type desk body parts are mutually independent and are assembled manually mainly through hinges, suckers and the like serving as connecting pieces. When the folding mode is folded, the occupied space is minimized through disassembly and assembly, however, the manual folding process is complicated, automatic control cannot be realized, and the folding mode is not suitable for the requirements of modern living furniture. Moreover, the existing folding table is only folded at one stage, cannot be adjusted at multiple stages, and cannot meet the use requirements of different table surface areas.

2. The lifting table is mainly realized by screw lifting, worm lifting and lever lifting. The screw type lifting mainly utilizes the relative movement of the screw and the sliding block to realize the lifting of the table body, so that the table body has larger bearing capacity and wider application; the worm type lifting mainly utilizes the relative movement of two worm pairs to realize the lifting of the table body, the bearing capacity is the largest in three modes, but is far greater than the common stress of a table top in daily life, and the processing difficulty and the manufacturing cost of the worm and the worm pairs are high, so that the table body is not suitable for use in real life; the lever type lifting is mainly realized by matching the lever and the hinge, the structural design is simple, and the manufacturing cost is also lowest, but when the lever is used as a table leg, the table top is unstable, and the lever type lifting is not suitable for lifting of medium-sized dining tables, and is only suitable for small-sized desks on beds. In conclusion, the three lifting modes are driven by manpower, so that the lifting and unfolding of the table are realized, and the operation is complex.

The invention comprises the following steps:

the invention aims at improving the problems in the prior art, namely the technical problem to be solved by the invention is to provide a liftable folding dining table and a working method thereof, which are reasonable in structural design, integrate folding and lifting, and are convenient to operate.

In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: the foldable dining table comprises table legs and a table top plate, wherein the table legs comprise lower table legs and upper table legs vertically sleeved outside the upper ends of the lower table legs in a sliding mode, the lower table legs are connected with vertically arranged lifting screws in a threaded mode, and a power mechanism A used for driving the lifting screws to rotate is arranged on the upper table legs; the desktop board comprises a fixed desktop board fixedly connected to the top of an upper desk leg and folding desktop boards symmetrically arranged on two sides of the fixed desktop board, the folding desktop board comprises a first-stage folding desktop board and a second-stage folding desktop board, the first-stage folding desktop board is located between the fixed desktop board and the second-stage folding desktop board, the first-stage folding desktop board is hinged to the fixed desktop board through a hinge, and a folding telescopic lever mechanism driven by a power mechanism B is arranged between the second-stage folding desktop board and the upper desk leg.

Further, the upper table leg comprises a horizontal supporting plate, the front end face and the rear end face of the horizontal supporting plate are respectively and fixedly connected with an upper bracket, the top of the upper bracket is fixedly connected with the bottom of the fixed table plate, and the bottom surface of the horizontal supporting plate is fixedly connected with two sleeves which are symmetrical in front-back; the lower table leg comprises two lower brackets which are arranged in a front-back symmetrical mode, the upper ends of the lower brackets extend into the sleeve on the same side and are in sliding connection with the sleeve, lifting screws are connected with the middle of the top surface of the lower brackets in a threaded mode, and the lifting screws upwards penetrate through the horizontal supporting plate.

Further, the power mechanism A comprises a driving motor A, a rotating shaft, driving bevel gears, driven bevel gears and a 90-degree bevel gear box, wherein the rotating shaft is longitudinally fixed on the upper side of the horizontal support plate through a gear steering bracket, the driving bevel gears are fixedly connected to the front end and the rear end of the rotating shaft respectively, and the driven bevel gears are fixedly connected to the upper end of the lifting screw and meshed with the driving bevel gears; the driving motor A is horizontally arranged, a motor shaft of the driving motor A is connected with the input end of the 90-degree bevel gear transmission box, and the output end of the 90-degree bevel gear transmission box is connected to the middle of the rotating shaft so as to drive the rotating shaft to rotate.

Further, the folding telescopic lever mechanism comprises a four-side connecting rod hinge assembly, an upper swing rod, a lower swing rod, a push rod, a swing connecting rod A, a swing connecting rod B and a sliding block, wherein the upper end of the four-side connecting rod hinge assembly is fixedly connected with the bottom surface of the secondary folding table plate, and the lower end of the four-side connecting rod hinge assembly forms a V-shaped extension part; the upper end of the upper swing rod is hinged with the upper end of the upper bracket, and the lower end of the upper swing rod is hinged with the lower end of the V-shaped extension part; the lower extreme of lower pendulum rod is articulated with the lower extreme of upper bracket, and the upper end of lower pendulum rod, the upper end of V-arrangement extension and swing connecting rod A keep away from the one end of fixed table mutually articulated, swing connecting rod A is close to the one end of fixed table, swing connecting rod B's upper end, go up the well upper portion of pendulum rod and the upper end of push rod mutually articulated, swing connecting rod B's lower extreme is articulated with the slider mutually, slider and lower pendulum rod sliding connection, the lower extreme of push rod is connected with power unit B, and power unit B drives the push rod and goes up and down.

Further, the four-side connecting rod hinging assembly comprises a horizontal connecting rod A, a horizontal connecting rod B, a middle connecting rod A and a middle connecting rod B, wherein the horizontal connecting rod A is fixedly connected to the bottom surface of the secondary folding table plate, one end of the horizontal connecting rod A, which is far away from the fixed table plate, is hinged with the upper end of the middle connecting rod A, and one end, which is close to the fixed table plate, is hinged with the upper end of the middle connecting rod B; the lower side of horizontal connecting rod A is located to horizontal connecting rod B, and horizontal connecting rod B is close to the one end of fixed table and forms V-arrangement extension with middle connecting rod B's lower extreme, middle upper portion and the horizontal connecting rod B of middle connecting rod B are articulated, and middle connecting rod B's lower extreme is articulated with the lower extreme of last pendulum rod, middle connecting rod A's lower extreme is articulated with the one end that horizontal connecting rod B kept away from fixed table.

Further, a supporting frame is fixedly connected between the lower ends of the two sleeves; the power mechanism B comprises a lifting screw rod and a guide rod, wherein the lifting screw rod and the guide rod are vertically arranged between the support frame and the horizontal support plate, the lifting screw rod is driven to rotate by a driving motor B arranged on the support frame, a lifting sliding block is connected to the lifting screw rod in a threaded manner, the lifting sliding block is vertically and slidably connected with the guide rod, and the left end and the right end of the lifting sliding block are respectively hinged with the lower ends of push rods of the folding telescopic lever mechanisms on the two sides.

Furthermore, the lower brackets are in an inverted T shape, and a reinforcing rod is fixedly connected between the two lower brackets.

Further, the motor control device also comprises a control unit, wherein the control unit comprises a singlechip and a power supply module, the singlechip is respectively and electrically connected with the driving motor A and the driving motor B through a motor driving module, and the power supply module is used for supplying power to the driving motor A and the driving motor B.

Further, the control unit further comprises a human body infrared sensor for detecting whether a person exists around the tabletop plate and a pressure sensor for detecting the gravity of the tabletop plate, the human body infrared sensor and the pressure sensor are electrically connected with the singlechip, and the singlechip receives signals detected by the human body infrared sensor and the pressure sensor and controls the driving motor A and the driving motor B to start and stop according to the received signals.

The invention adopts another technical scheme that: a working method of a liftable folding dining table comprises the following steps of:

(1) Lifting: the power output by the driving motor A drives the lifting screw rod to rotate through the rotating shaft, the driving bevel gear and the driven bevel gear, and the rotating motion of the lifting screw rod is converted into the vertical linear motion of the lower bracket in the sleeve barrel, so that the table top plate is lifted or lowered;

(2) Unfolding the table top plate: manually expanding the first-stage folding table plates at two sides of the fixed table plate upwards to be flush with the fixed table plate, then driving the lifting screw rod to rotate by the driving motor B, converting the rotation motion of the lifting screw rod into upward linear motion of the lifting slide block along the guide rod, and driving the folding telescopic lever mechanism to be upwards expanded while the lifting slide block moves upwards in a linear manner, so that the second-stage folding table plate is upwards expanded to be flush with the first-stage folding table plate and the fixed table plate;

(3) Folding a tabletop plate: the driving motor B drives the lifting screw rod to reversely rotate, the lifting screw rod drives the lifting sliding block to move linearly downwards along the guide rod, the lifting sliding block drives the folding telescopic lever mechanism to fold downwards while moving linearly downwards, the secondary folding table plate is folded downwards to the lower side of the primary folding table plate, and then the primary folding table plate is folded downwards manually.

Compared with the prior art, the invention has the following effects: the folding and unfolding table has the advantages of reasonable structural design, convenience in operation, integration of folding and lifting, automatic folding and unfolding of a common telescopic table, realization of folding and unfolding of the table top twice, capability of adjusting the size of the table top twice according to the number of people, and larger table top area.

Description of the drawings:

FIG. 1 is a schematic view of a front cross-sectional configuration of an embodiment of the present invention;

FIG. 2 is a schematic view of section A-A of FIG. 1;

FIG. 3 is a schematic top view of the power mechanism A;

FIG. 4 is a schematic perspective view of an embodiment of the present invention;

FIG. 5 is a schematic diagram of a front view configuration of an embodiment of the present invention;

figure 6 is a schematic perspective view of the secondary folding table as folded down;

figure 7 is a schematic front view of the primary folding table and the secondary folding table both folded downwardly;

fig. 8 is a control flow diagram of an embodiment of the present invention.

In the figure:

1-table legs; 2-a table top; 3-lower legs; 4-upper legs; 5-lifting screw rods; 6-a power mechanism A; 7-fixing the table plate; 8-a first-stage folding table plate; 9-a secondary folding table plate; 10-folding a telescopic lever mechanism; 11-a power mechanism B; 12-a horizontal support plate; 13-upper support; 14-a sleeve; 15-a lower bracket; 16-a drive motor a; 17-rotating shaft; 18-active bevel teeth; 19-driven bevel teeth; 20-90 degrees bevel gear box; 21-a gear steering rack; 22-four-sided link hinge assembly; 23-upper swing rod; 24-lower swing rod; 25-pushing rod; 26-swinging link a; 27-swinging a connecting rod B; 28-a slider; 29-V-shaped extension; 30-a horizontal connecting rod A; 31-a horizontal connecting rod B; 32-an intermediate link a; 33-intermediate link B; 34-supporting frames; 35-lifting screw rods; 36-a guide rod; 37-drive motor B; 38-lifting slide blocks; 39-reinforcing bars.

The specific embodiment is as follows:

the invention will be further described with reference to the drawings and examples for the purpose of more clearly explaining the invention, it being apparent that the drawings are only some of the embodiments of the invention.

As shown in fig. 1 to 7, the liftable folding dining table comprises a table leg 1 and a table top plate 2, wherein the table leg 1 comprises a lower table leg 3 and an upper table leg 4 vertically sleeved outside the upper end of the lower table leg 3 in a sliding manner, the lower table leg 3 is in threaded connection with a vertically arranged lifting screw 5, the upper table leg 4 is provided with a power mechanism A6 for driving the lifting screw 5 to rotate, and the lifting screw 5 is in threaded connection with the lower table leg 3, and the lower table leg 3 is in vertical sliding connection with the upper table leg 4, so that when the lifting screw 5 rotates, the rotary motion of the lifting screw 5 is converted into the vertical motion of the lower table leg 3 to realize lifting; the desktop board 2 includes the fixed table 7 that links firmly at upper portion table leg 4 top and the folding table of fixed table 7 both sides are located to the symmetry, folding table includes that one-level folding table 8 and second grade folding table 9, one-level folding table 8 is located between fixed table 7 and the second grade folding table 9, articulates mutually through the butterfly hinge between one-level folding table 8 and the fixed table 7, be equipped with between second grade folding table 9 and the upper portion table leg 4 by power unit B11 driven folding telescopic lever mechanism 10.

In this embodiment, the upper leg 4 includes a horizontal support plate 12, the front and rear end surfaces of the horizontal support plate 12 are respectively and fixedly connected with an upper bracket 13, the top of the upper bracket 13 is fixedly connected with the bottom of the fixed table 7, and the bottom surface of the horizontal support plate 12 is fixedly connected with two sleeves 14 which are symmetrical in front and back; the lower table leg 3 comprises two lower brackets 15 which are symmetrically arranged front and back, the upper ends of the lower brackets 15 extend into the sleeve 14 positioned on the same side and are in sliding connection with the sleeve 14, the middle part of the top surface of the lower brackets 15 is in threaded connection with a lifting screw 5, and the lifting screw 5 upwards penetrates through the horizontal supporting plate 12.

In this embodiment, the power mechanism A6 includes a driving motor a16, a rotating shaft 17, a driving bevel gear 18, a driven bevel gear 19, and a 90-degree bevel gear box 20, where the rotating shaft 17 is fixed on the upper side of the horizontal support plate 12 in the longitudinal direction by an L-shaped gear steering bracket 21, and the front and rear ends of the rotating shaft 17 are respectively and fixedly connected with the driving bevel gear 18, and the driven bevel gear 19 is fixedly connected with the upper end of the lifting screw 5 and meshed with the driving bevel gear 18; the driving motor A16 is horizontally arranged, a motor shaft of the driving motor A16 is connected with the input end of the 90-degree bevel gear transmission box 20, and the output end of the 90-degree bevel gear transmission box 20 is connected to the middle part of the rotating shaft 17 so as to drive the rotating shaft to rotate; the power output by the driving motor A drives the lifting screw rod to rotate through the rotating shaft, the driving bevel gear and the driven bevel gear, and the rotating motion of the lifting screw rod is converted into the vertical linear motion of the lower bracket in the sleeve barrel, so that the lifting or descending is realized.

In this embodiment, the folding telescopic lever mechanism 10 includes a four-side link hinge assembly 22, an upper swing link 23, a lower swing link 24, a push rod 25, a swing link a26, a swing link B27, and a slider 28, wherein the upper end of the four-side link hinge assembly 22 is fixedly connected with the bottom surface of the secondary folding table 9, and the lower end of the four-side link hinge assembly 22 forms a V-shaped extension 29; the upper end of the upper swing rod 23 is hinged with the upper end of the upper bracket 15, and the lower end of the upper swing rod 23 is hinged with the lower end of the V-shaped extension part 29; the lower extreme of lower pendulum rod 24 articulates with the lower extreme of upper bracket 13, and the upper end of lower pendulum rod 24, the upper end of V-arrangement extension 29 and the one end that swing connecting rod A26 kept away from fixed table 7 articulate, swing connecting rod A26 is close to the one end of fixed table 7, the upper end of swing connecting rod B27, the well upper portion of upper pendulum rod 23 and the upper end of push rod 25 articulate, the lower extreme of swing connecting rod B27 articulates with slider 28, slider 28 and lower pendulum rod 24 sliding connection, the lower extreme of push rod 25 is connected with power unit B11, and power unit B11 drives push rod 25 and goes up and down.

In this embodiment, the four-side link hinge assembly 22 includes a horizontal link a30, a horizontal link B31, a middle link a32, and a middle link B33, where the horizontal link a30 is fixedly connected to the bottom surface of the secondary folding table 9, one end of the horizontal link a30, far from the fixed table 7, is hinged to the upper end of the middle link a32, and one end, near the fixed table 7, is hinged to the upper end of the middle link B33; the horizontal connecting rod B31 is arranged on the lower side of the horizontal connecting rod A30, one end of the horizontal connecting rod B31, which is close to the fixed table plate 7, and the lower end of the middle connecting rod B33 form a V-shaped extension part 29, the middle upper part of the middle connecting rod B33 is hinged with the horizontal connecting rod B31, the lower end of the middle connecting rod B33 is hinged with the lower end of the upper swing rod 23, and the lower end of the middle connecting rod A32 is hinged with one end, which is far away from the fixed table plate 7, of the horizontal connecting rod B31.

In this embodiment, a supporting frame 34 is fixedly connected between the lower ends of the two sleeves 14; the power mechanism B11 comprises a lifting screw rod 35 and a guide rod 36 which are vertically arranged between the support frame 34 and the horizontal support plate 12, the lifting screw rod 35 is driven to rotate by a driving motor B37 arranged on the support frame 34, a lifting sliding block 38 is connected to the lifting screw rod 35 in a threaded manner, the lifting sliding block 38 is connected with the guide rod 36 in a sliding manner along the vertical direction, and the left end and the right end of the lifting sliding block 38 are hinged to the lower ends of push rods 25 of the folding telescopic lever mechanisms 10 on the two sides respectively.

In the embodiment, two folding telescopic lever mechanisms are arranged between each two-stage folding table plate and the upper table leg, the two folding telescopic lever mechanisms are symmetrically distributed in front-back mode and share one push plate, and the push plate is Y-shaped.

When the table top is to be folded in the unfolded state: the driving motor B37 drives the lifting screw rod 35 to rotate, the lifting screw rod 35 drives the lifting slide block 38 to move linearly downwards along the guide rod 36, the lifting slide block 38 drives the push rod 25 of the folding telescopic lever mechanism 10 to move downwards while moving linearly downwards, the push rod 5 drives the upper swing rod 23 and the lower swing rod 24 to swing in opposite directions while moving downwards, and the upper swing rod 23 and the lower swing rod 24 drive the four-side connecting rod hinge assembly 22 to fold downwards and shrink while swinging, so that the secondary folding table 9 is driven to move to the lower side of the primary folding plate 8 and close to the table leg 1; and then manually folding the primary folding table top 8 downwards to be close to the secondary folding table top 9, thereby completing the folding of the whole table top.

When the table top is to be unfolded from the collapsed position: the first-stage folding table plate 8 is manually turned upwards to be flush with the fixed table plate 7, then the driving motor B37 drives the lifting screw rod 35 to rotate, the rotary motion of the lifting screw rod 35 is converted into the upward linear motion of the lifting sliding block 38 along the guide rod, the lifting sliding block 38 drives the push rod 25 of the folding telescopic lever mechanism 10 to move upwards while moving upwards, the push rod 25 drives the upper swing rod 23 and the lower swing rod 24 to swing in opposite directions while moving upwards, the upper swing rod 23 and the lower swing rod 24 drive the four-side connecting rod hinge assembly 22 to be unfolded upwards while swinging, and then the second-stage folding table plate 9 is driven to be unfolded upwards to be flush with the first-stage folding table plate 8 and the fixed table plate 7, so that the unfolding of the table plate is completed.

In this embodiment, the lower brackets 15 are inverted T-shaped, and a reinforcing rod 39 is fixedly connected between the two lower brackets 15, so as to improve the structural strength of the entire lower leg.

In this embodiment, the control unit further includes a control unit, where the control unit includes a single chip microcomputer and a power module, the single chip microcomputer is electrically connected to the driving motor a and the driving motor B through the motor driving module, and the power module is used to supply power to the driving motor a and the driving motor B; preferably, the driving motor a and the driving motor B are both stepper motors. The singlechip determines the lifting speed and the lifting distance of the whole dining table through controlling the rotation direction, the movement speed and the rotation angle of the driving motor A and the driving motor B.

For control convenience, be provided with three adjusting button that is used for controlling driving motor A on the singlechip, three adjusting button corresponds the desktop board respectively and is apart from the height on ground: 800mm, 1000mm and 1200mm,800mm being the height suitable for children, 1000mm being the height suitable for adults, 1200mm being the height suitable for standing use; by setting the three adjusting buttons, free adjustment of three heights is realized.

In this embodiment, the control unit still includes the human infrared sensor that is used for detecting whether someone has around the desktop board and the pressure sensor that is used for detecting the gravity of desktop board, and human infrared sensor installs on the table leg, and pressure sensor installs, human infrared sensor and pressure sensor all are connected with the singlechip electricity, singlechip receives the signal that human infrared sensor and pressure sensor detected to start and stop according to received signal control driving motor A and driving motor B. When a person approaches the dining table, the human body infrared sensor sends high level to the singlechip, and under the condition that the primary folding table board is unfolded in advance, the singlechip controls the driving motor B to start, and the driving motor B drives the sliding block to drive the push rod to move upwards, so that the secondary folding table board is unfolded upwards automatically, and the unfolding of the table board is completed; when no person exists around the desktop and the desktop does not exist, the human body infrared sensor sends low level to the singlechip and the pressure sensor is low level, and the secondary folding table board is automatically folded downwards and contracted to the lower side of the primary folding table board.

In this embodiment, when the first stage folding table top is unfolded upward, the size of the table top is 800mm (width) x 1100mm (length); when the secondary folding table top is also unfolded upward, the size of the table top is 800mm (width) by 1700mm (length).

In the embodiment, the singlechip is an 80C52 singlechip; the driving motor A and the driving motor B are 86HYGH3 stepping motors, and the model of a motor driving module is TB6600.

(1) Lifting: the lifting screw 5 is driven to rotate by the power output by the driving motor A16 through the rotating shaft 17, the driving bevel gear 18 and the driven bevel gear 19, the rotation motion of the lifting screw 5 is converted into the vertical linear motion of the lower bracket 15 in the sleeve 14, the extension and retraction of the lower table leg 3 are completed, and then the lifting or the lowering of the table top 2 is realized;

(2) Unfolding the table top plate: manually expanding the first-stage folding table plates 8 on two sides of the fixed table plate 7 upwards to be flush with the fixed table plate 7, then driving the lifting screw rod 35 to rotate by the driving motor B37, converting the rotation motion of the lifting screw rod 35 into upward linear motion of the lifting sliding block 38 along the guide rod 36, and driving the folding telescopic lever mechanism 10 to be expanded upwards while the lifting sliding block 38 moves upwards in a linear manner, so that the second-stage folding table plate 9 is expanded upwards to be flush with the first-stage folding table plate 8 and the fixed table plate 7;

(3) Folding a tabletop plate: the driving motor B37 drives the lifting screw rod 35 to reversely rotate, the lifting screw rod 35 drives the lifting slide block to linearly move downwards along the guide rod 36, the lifting slide block 38 drives the folding telescopic lever mechanism 10 to fold downwards and shrink when linearly moving downwards, so that the secondary folding table plate 9 is folded downwards to the lower side of the primary folding table plate 8 and is close to the table legs, and then the primary folding table plate 8 is folded downwards to be close to the secondary folding table plate 9 manually.

The foregoing description is only of the preferred embodiments of the invention, and all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims

1. The utility model provides a liftable folding dining table, includes table leg and desktop board, its characterized in that: the table legs comprise lower table legs and upper table legs vertically sleeved outside the upper ends of the lower table legs in a sliding mode, the lower table legs are connected with vertically arranged lifting screws in a threaded mode, and a power mechanism A used for driving the lifting screws to rotate is arranged on the upper table legs; the desktop plate comprises a fixed desktop plate fixedly connected to the top of the upper desktop leg and folding desktop plates symmetrically arranged on two sides of the fixed desktop plate, the folding desktop plate comprises a first-stage folding desktop plate and a second-stage folding desktop plate, the first-stage folding desktop plate is positioned between the fixed desktop plate and the second-stage folding desktop plate, the first-stage folding desktop plate is hinged with the fixed desktop plate through a hinge, and a folding telescopic lever mechanism driven by a power mechanism B is arranged between the second-stage folding desktop plate and the upper desktop leg;

the upper table leg comprises a horizontal supporting plate, the front end surface and the rear end surface of the horizontal supporting plate are respectively fixedly connected with an upper bracket, the top of the upper bracket is fixedly connected with the bottom of the fixed table plate, and the bottom surface of the horizontal supporting plate is fixedly connected with two sleeves which are symmetrical in front-back; the lower table leg comprises two lower brackets which are symmetrically arranged front and back, the upper ends of the lower brackets extend into the sleeves positioned on the same side and are in sliding connection with the sleeves, the middle part of the top surface of the lower bracket is in threaded connection with a lifting screw rod, and the lifting screw rod upwards penetrates through the horizontal supporting plate;

the folding telescopic lever mechanism comprises a four-side connecting rod hinge assembly, an upper swing rod, a lower swing rod, a push rod, a swing connecting rod A, a swing connecting rod B and a sliding block, wherein the upper end of the four-side connecting rod hinge assembly is fixedly connected with the bottom surface of the secondary folding table plate, and the lower end of the four-side connecting rod hinge assembly forms a V-shaped extension part; the upper end of the upper swing rod is hinged with the upper end of the upper bracket, and the lower end of the upper swing rod is hinged with the lower end of the V-shaped extension part; the lower end of the lower swing rod is hinged with the lower end of the upper bracket, the upper end of the lower swing rod, the upper end of the V-shaped extension part and one end of the swing connecting rod A, which is far away from the fixed table plate, are hinged with one end of the swing connecting rod A, which is close to the fixed table plate, the upper end of the swing connecting rod B, the upper middle part of the upper swing rod and the upper end of the push rod, the lower end of the swing connecting rod B is hinged with the sliding block, the sliding block is in sliding connection with the lower swing rod, the lower end of the push rod is connected with the power mechanism B, and the power mechanism B drives the push rod to lift;

two folding telescopic lever mechanisms are arranged between each two-stage folding table plate and the upper table leg, and the two folding telescopic lever mechanisms are symmetrically distributed front and back.

2. The liftable folding dining table of claim 1, wherein: the power mechanism A comprises a driving motor A, a rotating shaft, driving bevel gears, driven bevel gears and a 90-degree bevel gear box, wherein the rotating shaft is longitudinally fixed on the upper side of a horizontal support plate through a gear steering bracket, the driving bevel gears are fixedly connected with the front end and the rear end of the rotating shaft respectively, and the driven bevel gears are fixedly connected with the upper end of a lifting screw and meshed with the driving bevel gears; the driving motor A is horizontally arranged, a motor shaft of the driving motor A is connected with the input end of the 90-degree bevel gear transmission box, and the output end of the 90-degree bevel gear transmission box is connected to the middle of the rotating shaft so as to drive the rotating shaft to rotate.

3. The liftable folding dining table of claim 1, wherein: the four-side connecting rod hinging assembly comprises a horizontal connecting rod A, a horizontal connecting rod B, a middle connecting rod A and a middle connecting rod B, wherein the horizontal connecting rod A is fixedly connected to the bottom surface of the secondary folding table plate, one end of the horizontal connecting rod A, which is far away from the fixed table plate, is hinged with the upper end of the middle connecting rod A, and one end of the horizontal connecting rod A, which is close to the fixed table plate, is hinged with the upper end of the middle connecting rod B; the lower side of horizontal connecting rod A is located to horizontal connecting rod B, and horizontal connecting rod B is close to the one end of fixed table and forms V-arrangement extension with middle connecting rod B's lower extreme, middle upper portion and the horizontal connecting rod B of middle connecting rod B are articulated, and middle connecting rod B's lower extreme is articulated with the lower extreme of last pendulum rod, middle connecting rod A's lower extreme is articulated with the one end that horizontal connecting rod B kept away from fixed table.

4. The liftable folding dining table of claim 1, wherein: a supporting frame is fixedly connected between the lower ends of the two sleeves; the power mechanism B comprises a lifting screw rod and a guide rod, wherein the lifting screw rod and the guide rod are vertically arranged between the support frame and the horizontal support plate, the lifting screw rod is driven to rotate by a driving motor B arranged on the support frame, a lifting sliding block is connected to the lifting screw rod in a threaded manner, the lifting sliding block is vertically and slidably connected with the guide rod, and the left end and the right end of the lifting sliding block are respectively hinged with the lower ends of push rods of the folding telescopic lever mechanisms on the two sides.

5. The liftable folding dining table of claim 1, wherein: the lower support is of an inverted T shape, and a reinforcing rod is fixedly connected between the two lower supports.

6. The liftable folding table of claim 2 or 4, wherein: the control unit comprises a singlechip and a power supply module, wherein the singlechip is respectively and electrically connected with the driving motor A and the driving motor B through a motor driving module, and the power supply module is used for supplying power to the driving motor A and the driving motor B.

7. The liftable folding table of claim 6, wherein: the control unit also comprises a human body infrared sensor for detecting whether a person exists around the tabletop plate and a pressure sensor for detecting the gravity of the tabletop plate, wherein the human body infrared sensor and the pressure sensor are electrically connected with the singlechip, and the singlechip receives signals detected by the human body infrared sensor and the pressure sensor and controls the driving motor A and the driving motor B to start and stop according to the received signals.

8. A working method of a liftable folding dining table is characterized in that: comprising a foldable table according to any one of claims 1 to 7, which is liftable, in operation: