TW202037826A - Lifting platform - Google Patents

Abstract

Provided by the present invention is a lifting platform. The lifting platform comprises a table, an energy conversion device (30) connected below the table and a leg assembly. The energy conversion device (30) is used to convert elastic potential energy into auxiliary energy for lifting the table, and comprises a torsion spring (31), a middle shaft (33) and a transmission (32); a first end of the torsion spring (31) is connected to an input part of the transmission (32); and the middle shaft (33) is connected to an output part of the transmission (32). The rotation speed of the input part is less than that of the output part. The leg assembly is connected to the middle shaft (33). During a process of forward rotation or reverse rotation of the middle shaft (33), the leg assembly is shortened or elongated to cause the table to descend or rise. According to the lifting table of the present invention, elastic potential energy stored by the torsion spring is not completely released during the entire rising process of the table, so that the external force required by the table from an operator is small.

Description

Lifts

The present invention relates to the field of furniture or the field of production equipment, in particular to a lifting platform that can be changed in height. The lifting platform can be expressed as a table, chair, console or display table, etc., and is suitable for home furniture, office furniture, teaching tables and chairs, and Workbench for production, etc.

The lifting platform in the prior art is usually manually operated by an operator to change the height of the platform. In order to reduce the difficulty of the operator's work, the lifting platform may include an energy storage device (hereinafter also referred to as an energy storage device). For example, in a lifting platform that uses a torsion spring as an energy storage device, you can accumulate the elastic potential energy by turning the torsion spring to make the torsion spring rotate several times around its axis, and then release the elastic potential energy when the platform needs to rise. To provide auxiliary energy to help the table rise. As the table rises and falls, the elastic potential energy of the torsion spring and the gravity potential energy of the table are mutually converted.

Assuming that the table top of the lifting platform rises from the lowest position (for example, 700mm from the ground) to the highest position (for example, 1200mm from the ground), the maximum stroke is 500mm. During the entire ascent of the table, the torsion spring needs to rotate 5 times, that is, every time the torsion spring rotates. Circle, the table rises 100mm.

Assuming that the length of the torsion arm of the torsion spring is 0.025m, the torque required for each turn of the torsion spring is 0.75N∙m, which means that the elastic potential energy is 0.75N∙m. When the torsion spring rotates one circle, the torque generated by it is 0.75N∙m/0.025m=30N; when the torsion spring rotates two times, the torque generated by it is 60N.

Assuming that the total load of the table is 150N, I want to raise the table from the lowest position to the highest position. Turn the torsion spring 5 times in advance, the stored elastic potential energy of the torsion spring is 5×0.75N∙m=3.75N∙m, and the torsion spring generates a torsion force of 150N, which is balanced with the total load of the table. At this time, give the table an upward initial momentum, and the table can rise.

When the table is raised by 100mm, the torsion spring rotates (turns in the opposite direction to the preset direction) once, releasing the potential energy of 0.75N∙m. At this time, the stored potential energy of the torsion spring is reduced to 3.75N∙m- 0.75N∙m=3N∙m, the corresponding external torque is 3N∙m/0.025m=120N. At this time, to keep the table top rising at a constant speed, the operator needs to apply an additional 30N upward force to the table top.

By analogy, in order to ensure the stable rise of the table, the upward force (hereinafter referred to as the external force) exerted by the operator on the table must be continuously increased during the continuous rise of the table. When the table is raised by 200mm, the required external force is 60N; when the table is raised by 400mm, the required external force is 120N. The ever-increasing demand for external forces has brought a greater burden to operators.

Therefore, the purpose of the present invention is to overcome or at least alleviate the above-mentioned shortcomings of the prior art, and provide a lifting platform that can provide continuous and stable auxiliary force.

The present invention provides a lifting platform, which includes a platform, an energy conversion device and a leg assembly connected below the platform, wherein:

The energy conversion device is used to convert elastic potential energy into auxiliary energy for lifting the table, and includes a torsion spring, a bottom bracket, and a transmission. The first end of the torsion spring is connected to the input element of the transmission. The bottom bracket is connected to the output element of the transmission, the rotation speed of the input element is less than the rotation speed of the output element,

The leg assembly is connected with the central shaft, and during the forward or reverse rotation of the central shaft, the leg assembly is shortened or elongated to cause the table top to fall or rise.

In at least one embodiment, the transmission is a planetary gear transmission, which includes a ring gear, a sun gear, several planet gears and a planet carrier;

The ring gear is fixed, the planet carrier is connected to the torsion spring as the input element, and the sun gear is connected to the bottom shaft as the output element;

The torsion spring is sleeved on the outer circumference of the central shaft and arranged coaxially with the central shaft.

In at least one embodiment, the transmission includes a large gear as the input element and a small gear as the output element, and rotation axes of the large gear and the small gear are not collinear.

In at least one embodiment, the lifting platform further includes a beam fixed to the platform, and the energy conversion device further includes a clutch, a brake fork, and a transmission assembly;

The clutch is fixed to the beam, and the middle shaft passes through the clutch so as to rotate around its own axis;

The brake fork is fixed to the bottom shaft, and the brake fork can be selectively locked or released by the clutch; when the brake fork is locked by the clutch, the bottom shaft cannot rotate; when the brake When the fork is released by the clutch, the middle shaft can rotate around its own axis;

The transmission assembly is connected to the second end of the torsion spring, and the second end of the torsion spring can be rotated relative to the first end by operating the transmission assembly, so that the torsion spring can accumulate an elastic position. can.

In at least one embodiment, the leg assembly includes a first leg, a second leg, and a synchronous lifting device. The first leg can approach or move away from the second leg along the axial direction of the second leg. Legs,

The synchronous lifting device includes:

The support frame is a long strip;

Two transmission wheels are arranged at the two ends of the support frame;

An annular transmission member is tightly sleeved on the two transmission wheels by the two transmission wheels; and

The synchronization connector is fixed to the annular transmission member; wherein,

The bottom bracket is connected to the annular transmission member, the support frame is fixedly connected to the first leg, and the synchronization connector is fixedly connected to the second leg.

In at least one embodiment, the first leg is sleeved on the outer circumference of the second leg.

In at least one embodiment, the energy conversion device further includes an outer stub shaft, and the outer stub shaft is movably nested and arranged at the end of the center shaft and the center shaft along the axial direction of each other.

In at least one embodiment, a spring is provided at the connection between the outer stub shaft and the central shaft, and the outer stub shaft can be close to the central shaft by pressing the spring.

In at least one embodiment, the leg assembly further includes a pressure cylinder, the cylinder of the pressure cylinder is fixedly connected to the support frame, and the piston rod of the pressure cylinder is fixedly connected to the second leg.

In at least one embodiment, the piston of the pressure cylinder divides the cylinder into a first chamber and a second chamber, the first chamber and the second chamber are in fluid communication, and the piston rod Extend the cylinder from the second chamber,

The cylinder is divided into a first area and a second area in the axial direction, the second area is closer to the protruding end of the piston rod than the first area,

In the first area, the inner diameter of the cylinder gradually becomes larger in the direction from the first chamber to the second chamber, and in the second area, the inner diameter of the cylinder Keep constant in the direction from the first chamber to the second chamber.

According to the lifting platform of the present invention, the elastic potential energy stored by the torsion spring is not completely released during the whole process of the platform ascending, so that the external force from the operator required by the platform is relatively small.

The exemplary embodiments of the present invention are described below with reference to the drawings. It should be understood that these specific descriptions are only used to teach those skilled in the art how to implement the present invention, not to exhaust all possible ways of the present invention, nor to limit the scope of the present invention.

Hereinafter, referring to Figures 1 to 8, the specific structure and use method of the lifting platform according to the present invention will be introduced.

1, the lifting platform of this embodiment includes a platform (not shown in the figure), a hollow beam 10 fixed below the platform, an energy conversion device 30 accommodated in the cavity of the beam 10, and fixed on both sides of the beam 10 Two hollow legs 20, a synchronous lifting device 40 (see FIG. 6) and a pressure cylinder 50 (see FIG. 6) accommodated in the inner cavity of the leg 20.

The energy conversion device 30 is used to provide the first auxiliary energy (first auxiliary energy) during the lifting process of the lifting part of the lifting platform (the lifting part mainly includes the table top, the following description is simple, and when the lifting part is mentioned, only the table top is used instead). Power), the elastic potential energy accumulated by the energy storage device in the energy conversion device 30 can be converted into the gravity potential energy of the table, thereby reducing the burden on the operator.

1 and 2, the energy conversion device 30 includes a torsion spring 31, a transmission 32, a bottom shaft 33, an outer short shaft 34, a clutch 35, a brake fork 36 and a transmission assembly 37.

The clutch 35 is fixed to the cross beam 10, and the central shaft 33 passes through the clutch 35 and can rotate about its own axis relative to the clutch 35. The brake fork 36 is fixed to the bottom bracket 33, and the brake fork 36 can be selectively locked or released by the clutch 35 through the clutch switch 351. When the brake fork 36 is released by the clutch 35, the center shaft 33 can rotate in a forward or reverse direction; when the brake fork 36 is locked by the clutch 35, the center shaft 33 cannot rotate.

The torsion spring 31 is sleeved on the outer circumference of the central shaft 33, the first end of the torsion spring 31 is connected to the central shaft 33 through the transmission 32, and the second end of the torsion spring 31 is connected to the transmission assembly 37. The transmission assembly 37 is used for transmitting the external force to the second end of the torsion spring 31 to make the torsion spring 31 rotate around its own axis. In this embodiment, the transmission assembly 37 is a worm gear assembly. The transmission assembly 37 is connected to the handle 371. The rotation axis of the handle 371 is perpendicular to the rotation axis of the torsion spring 31. The operator can transmit the external force to the torsion spring 31 by turning the handle 371. An indicating device 372 is also provided on the wall of the beam 10, and the rotation range of the handle 371 can be displayed by the indicating device 372. The indicating device 372 may be a mechanical pointer, which is linked with the handle 371 through a transmission such as a gear and rack; or a digital dial, which measures the rotation amplitude of the handle 371 through a photoelectric sensor or the like. The operator can know the relative magnitude of the energy stored by the torsion spring 31 through the indicating device 372.

The way of accumulating elastic potential of the torsion spring 31 is to control the clutch switch 351 so that the brake fork 36 is locked by the clutch 35. At this time, when the handle 371 is rotated, the first end of the torsion spring 31 is fixed and the second end is rotated.

The realization of the release of the elastic potential energy of the torsion spring 31: the handle 371 is locked and the second end of the torsion spring 31 is fixed. At this time, the clutch switch 351 is controlled so that the brake fork 36 is released by the clutch 35, and the first end of the torsion spring 31 is opposite It rotates at the second end and drives the central shaft 33 to rotate.

The transmission 32 connects the torsion spring 31 and the central shaft 33 so that the rotation of the torsion spring 31 is amplified and transmitted to the central shaft 33. In conjunction with the following readers will understand that the table lifts a certain distance and the number of rotations of the center shaft 33 is fixed. If the center shaft 33 rotates several times, the torsion spring 31 only rotates a small angle, then in the process of rising the table, The elastic potential of the torsion spring 31 is not completely released. For the same rising distance, compared to the adjustment process in which the elastic position of the torsion spring 31 is completely released, the auxiliary force provided by the torsion spring 31 in this embodiment changes little, so the rise of the table is more stable and requires the operator's dynamic The external force to supplement the ground is smaller.

3 and 4, the specific structure and function of the transmission 32 according to this embodiment will be described below. In order to save the space in the inner cavity of the beam 10 (see FIG. 1) and facilitate the position setting of the bottom bracket 33 (see FIG. 2) and the torsion spring 31 (see FIG. 2), the transmission 32 used in this embodiment is a planetary gear transmission. The transmission 32 includes a planet carrier 321, a sun gear 322, three planet gears 323, a ring gear 324 and a housing 325. The planet carrier 321 is used for fixing to the first end of the torsion spring 31, and the planet wheel 323 is fixed to the planet carrier 321 so as to rotate around its own axis. The central shaft 33 axially passes through the sun gear 322 and is connected to the sun gear 322 in a relatively non-rotatable manner. The outer circumference of the ring gear 324 has a number of notches, and these notches can cooperate with the protrusions in the housing 325 so that the ring gear 324 is fixed by the housing 325.

The operation process of the transmission 32 corresponds to the process of releasing the elastic potential energy of the torsion spring 31. During this process, the ring gear 324 does not move, the planet carrier 321 is active, and the sun gear 322 is passive, and the transmission effect of acceleration from the planet carrier 321 to the sun gear 322 is realized.

Next, taking the transmission ratio (that is, the rotational speed (angular speed) ratio) between the planet carrier 321 and the sun gear 322 of 1:10 as an example, the advantages of installing the transmission 32 in the present invention are described. The auxiliary support for the table discussed here does not consider the impact of the cylinder assembly described below.

Assuming that the torsion arm length of the torsion spring 31 is 0.025m, the torque of 7.5N∙m is required for each revolution of the torsion spring 31, which means that the potential energy is 7.5N∙m. Therefore, for each revolution of the torsion spring 31, the force transmitted to the central shaft 33 through the transmission 32 is 7.5N∙m/0.025m/10=30N.

For a table with a load of 150N that needs to be raised by 500 mm, it is assumed that the table is raised by 100 mm for every rotation of the central shaft 33. When defining the initial state, the torsion spring 31 is preset to rotate 5 turns in the forward direction, so that the torsion spring 31 stores the elastic potential energy of 5×7.5N∙m=37.5N∙m, and the force transmitted to the central shaft 33 through the transmission 32 is 37.5N∙ m/0.025m/10=150N. At this time, the supporting force provided by the torsion spring 31 to the table is balanced with the load of the table, and the table can be raised by giving the table a slight upward initial momentum.

After the table is raised by 100mm, the central shaft 33 rotates one turn, the torsion spring 31 rotates 1/10 turns (36°) in the opposite direction to the preset rotation direction, and the torsion spring 31 releases the elastic potential energy of 7.5N∙m×1/10 =0.75N∙m. At this time, the stored elastic potential energy of the torsion spring 31 is reduced to 37.5N∙m-0.75N∙m=36.75N∙m, and the force transmitted by the torsion spring 31 to the central shaft 33 through the transmission 32 is reduced to 36.75N∙m/0.025m /10=147N. Compared with the initial state, the supporting force provided to the table by the torsion spring 31 is reduced by 3N. At this time, the operator only needs to provide an additional 3N upward external force to the table, and the table can still rise at a constant speed.

By analogy, when the table is raised by 200mm, the required external force is 6N; when the table is raised by 400mm, the required external force is 12N. When the table is raised by 500mm, the torsion spring 31 rotates 5/10 times (180°) in reverse, releasing the elastic potential energy of 3.75N∙m. At this time, the stored elastic potential energy of the torsion spring 31 is reduced to 37.5N∙m- 3.75N∙m=33.75N∙m, the force transmitted by the torsion spring 31 to the central shaft 33 through the transmission 32 is reduced to 33.75N∙m/0.025m/10=135N. Compared with the initial state, the supporting force provided to the table by the torsion spring 31 is only reduced by 15N.

Therefore, compared with the solution in the prior art that does not use the transmission 32, the external force provided by the operator is greatly reduced during the 500mm rise of the table.

Next, referring to FIGS. 5 to 7, it will be described how the rotation of the central shaft 33 (see FIG. 2) drives the table top to rise and fall.

The synchronous lifting device 40 connects the central shaft 33 and the legs 20 (see Figure 1). The synchronous lifting device 40 can not only realize the conversion between the rotation of the central shaft 33 and the telescopic movement of the legs 20, but also ensure that the two legs 20 can be synchronized. Retractable.

5, the synchronous lifting device 40 includes a supporting frame 41, a transmission chain 42, a synchronous connector 43 and a phase connector 44. The support frame 41 is in a long strip shape, and two ends of the support frame 41 are respectively connected with a phase connector 44, and each phase connector 44 includes a transmission wheel. The ring-shaped transmission chain 42 is sleeved on the transmission wheels of the two phase connectors 44 and is tensioned. The synchronization connector 43 is fixed to the transmission chain 42, and the forward and reverse rotation of the transmission chain 42 will drive the synchronization connector 43 to reciprocate between the two phase connectors 44. The rotation of the transmission chain 42 is synchronized with the rotation of the transmission wheel. The rotation of the transmission wheel drives the rotation of the connecting ring 441. The connecting ring 441 can be connected non-rotatably with the central shaft 33; therefore, the rotation of the central shaft 33 and the synchronization of the connector 43 The reciprocating movement restrains each other.

1, 5 and 6, the connection relationship between the synchronous lifting device 40 and the leg 20 will be described. The leg 20 includes a first leg 21 and a second leg 22 nested in each other, and the first leg 21 and the second leg 22 can be close to or far away from each other, so that the leg 20 can be shortened or extended. The support frame 41 of the synchronous lifting device 40 is fixedly connected to the first leg 21, and the synchronous connector 43 is fixedly connected to the second leg 22. Therefore, when the relative position of the first leg 21 and the second leg 22 changes, the position of the synchronization connector 43 on the support frame 41 also changes correspondingly, and the connecting ring 441 rotates at the same time. In this embodiment, since the first leg 21 and the second leg 22 are nested with each other, in order to make the first leg 21 and the second leg 22 move relative to each other, they will not interact with the synchronization connector 43. Position interference, the first leg 21 is sleeved on the outer periphery of the second leg 22.

Next, referring to FIGS. 1, 2 and 7, how the center shaft 33 is connected to the phase connector 44 will be described. The beam assembly (including the beam 10 and the energy conversion device 30) of this embodiment can be easily disassembled and assembled with the leg assembly (including the leg 20, the synchronous lifting device 40, and the pressure cylinder 50 (see FIG. 6) described further below), so that In the process of transporting the lifting platform from the manufacturer to the customer, it can be packaged and transported independently, saving logistics costs. The flexible disassembly and assembly of the beam assembly and the leg assembly is realized by the outer short shaft 34 and the spring 341. The two ends of the central shaft 33 are arranged in a hollow structure, and the outer short shaft 34 can be inserted into the inner cavity at the end of the central shaft 33 and connected to the central shaft 33 in a non-rotatable manner, such as the cross section of the inner cavity at the end of the central shaft 33 and the outer short shaft 34 The cross-sections are all hexagons. A spring 341 is provided where the outer short shaft 34 and the central shaft 33 are sleeved. In a natural state, the spring 341 maintains the original length, and the outer short shaft 34 is in an extended state. When the outer stub shaft 34 applies pressure toward the central shaft 33 in the axial direction, the outer stub shaft 34 can further extend into the inner cavity of the central shaft 33. The cross-sectional shape of the outer short shaft 34 is adapted to the cross-sectional shape of the annular hole of the connecting ring 441, so that the outer short shaft 34 can just extend into the connecting ring 441, and the outer short shaft 34 or one of the connecting ring 441 Rotation can drive the other to rotate in the same phase, and the phase of the rotation of the two is mutually restricted, that is, the two cannot be connected in relative rotation.

Preferably, the distance between the two legs 20 of the assembled lifting platform (approximately equal to the distance between the two connecting rings 441) is smaller than the extension ends of the two outer short shafts 34 of the energy conversion device 30 in a natural state the distance between. Therefore, when the beam assembly and the leg assembly are installed, the outer stub shaft 34 is at least partially pressed into the central shaft 33 until the two outer stub shafts 34 both extend into the corresponding connecting ring 441. Afterwards, the outer short shaft 34 is partially rebounded out of the central shaft 33 under the action of the elastic force of the spring 341, so that the assembly relationship between the beam assembly and the leg assembly is stronger.

It should be understood that the telescopic assembly of the outer stub shaft 34 and the central shaft 33 is not limited to the form in which the outer stub shaft 34 is nested inside the central shaft 33 as described above. For example, the end of the outer stub shaft 34 connected to the central shaft 33 can also be set to a hollow structure, so that the central shaft 33 can partially extend into the inside of the outer stub shaft 34.

1, 5 and 8, the pressure cylinder 50 in this embodiment (refer to FIG. 8) provides the second auxiliary energy (second auxiliary power) for the rise of the table. In this embodiment, the pressure cylinder 50 is a pneumatic cylinder, and the cylinder 51 is filled with high-pressure nitrogen. The cylinder 51 is fixedly connected to the support frame 41 or the first leg 21, and the piston rod 52 is fixedly connected to the second leg 22. During the rising of the table, the piston rod 52 continues to extend out of the cylinder 51 to provide auxiliary power.

Preferably, in order to keep the output force of the piston rod 52 stable during the extension process, the inner diameter of the pressure cylinder 50 has a special design. This is because, because the piston rod 52 occupies a certain space inside the cylinder 51, the gas volume inside the cylinder 51 gradually increases as the piston rod 52 extends outward, and the gas pressure inside the cylinder 51 slowing shrieking. If the surface areas of the upper and lower surfaces of the piston 53 remain unchanged, the outward output force of the piston rod 52 will continue to decrease during the entire process of the piston rod 52 extending outward. In the preferred solution introduced below, the inner diameter of the cylinder 51 changes in the axial direction, so that the surface area of the upper and lower surfaces of the piston 53 also changes correspondingly during the movement.

The structure of this preferred pressure cylinder 50 is described below with reference to FIG. 8.

The inside of the cylinder 51 is divided into a first chamber C1 and a second chamber C2 in the axial direction by the piston 53, and the first chamber C1 and the second chamber C2 are in fluid communication.

According to the difference of the inner diameter of the cylinder 51, the cylinder 51 is divided into two areas in the axial direction, defining the extension direction of the piston rod 52 as "up", and the second area is located above the first area. In the direction from the first area to the second area in the axial direction of the cylinder 51, the inner diameter of the cylinder 51 in the first area gradually increases, and the inner diameter of the cylinder 51 in the second area remains unchanged.

The piston 53 has a certain elasticity, can be in close contact with the inner wall of the cylinder 51 and deforms adaptively according to the change of the inner diameter of the cylinder 51. During the movement of the piston rod 52 out of the cylinder 51, when the piston 53 moves in the first area, the upper and lower surfaces of the piston 53 (the surface of the piston 53 facing the first chamber C1 is its lower surface, The surface area of the piston 53 facing the second chamber C2 is its upper surface). The surface area difference ΔS gradually decreases; and when the piston 53 moves in the second zone, the surface area difference ΔS' between the upper and lower surfaces of the piston 53 remains constant. The dotted lines in FIG. 8 are schematic diagrams of several positions in the movement track of the piston 53. Table 1 shows the difference in surface area between the upper and lower surfaces of the piston 53 at the above positions. It is worth noting that the design of the inner diameter of the cylinder body 51 in practical applications needs to be carried out in consideration of the external force received by the piston rod 52 and the physical state of the high-pressure nitrogen in the cylinder, the structure of the device, and the setting of the gas valve.

Table 1 Piston position Lower surface diameter/mm Top surface diameter/mm Surface area difference on both sides of the piston/mm² 1 30.0000 30.0784 15.9275 △S 2 30.6667 30.7451 15.8455 3 31.3333 31.4118 15.7585 4 32.0000 32.0000 19.6250 △S' 5 32.0000 32.0000 19.6250 6 32.0000 32.0000 19.6250 7 32.0000 32.0000 19.6250

The whole process of the extension of the piston rod 52 is: △S<△S', the surface area difference adaptively compensates the gas pressure difference in the cylinder 51 during this process, so that the output force of the piston rod 52 changes more Small, the auxiliary power provided by the pressure cylinder 50 is relatively stable.

The following describes the lifting operation process of the lifting platform according to this embodiment with reference to Figs. 1 and 2:

(1) Lifting platform rises

In the initial state, the clutch switch 351 is in the connected state, and the brake fork 36 is locked by the clutch 35.

Rotating the handle 371 causes the torsion spring 31 to rotate positively and accumulate energy, and combined with the reading of the indicating device 372, the torsion spring 31 can accumulate elastic potential energy suitable for the total load of the table.

The clutch switch 351 is turned off. The brake fork 36 is disengaged from the lock of the clutch 35, the torsion spring 31 rotates in the reverse direction to release the elastic potential energy, and drives the central shaft 33 and the outer short shafts 34 at both ends to rotate through the transmission 32 to transmit the first auxiliary power to the synchronous lifting device 40.

Supported by the second auxiliary power provided by the pressure cylinder 50 and the above-mentioned first auxiliary power, the table surface is close to a suspended state. At this time, the table can be slightly lifted to give the table an upward initial momentum, and the piston rod 52 of the pressure cylinder 50 extends. The legs 20 extend (the first leg 21 rises at a nearly uniform speed), and the rising of the first leg 21 on both sides is kept synchronized.

During the ascent of the table, the operator can give the table a certain artificial force according to the movement state of the table.

After the platform reaches the expected height, the clutch switch 351 is in the connected state, and the brake fork 36 is locked by the clutch 35. The elongation process of the leg 20 (that is, the ascending process of the table top) is terminated, the height of the lifting platform is determined, and the gravity potential of the table top is increased.

(2) The lifting platform descends

The clutch switch 351 is in the off state, the brake fork 36 is released from the lock of the clutch 35, and the central shaft 33 and the outer short shafts 34 at both ends are in a rotatable state.

Lightly pressing the table top gives the table a downward initial momentum, and the table tops down under its own gravity. During the lowering of the table, the central shaft 33 rotates in the forward direction (relative to the reverse rotation of the central shaft 33 and the torsion spring 31 during the ascending process of the lifting platform), which drives the brake fork 36 and the torsion spring 31 to rotate forward, and the torsion spring 31 stores energy.

After the platform reaches the expected height, the clutch switch 351 is connected, the brake fork 36 is locked by the clutch 35, the descending process is terminated, the height of the lifting platform is determined, and the gravity potential of the platform is converted into the elastic potential of the torsion spring 31.

The present invention has at least one of the following advantages:

(I) The present invention uses the torsion spring 31 to provide the first auxiliary power for the elevation of the lifting platform, and the auxiliary power is transmitted to the central shaft 33 via the transmission 32 and further to the synchronous lifting device 40. The transmission 32 acts like a lever in the process of transmitting force and motion. It enlarges the rotation angle of the torsion spring 31 and transmits it to the central shaft 33, so that the elasticity of the torsion spring 31 is accumulated during the whole process of rising of the table. Could it all be released.

(Ii) The transmission 32 adopts a planetary gear transmission structure. The torsion spring 31 is connected to the planet carrier 321 as the input element of the transmission 32, and the bottom shaft 33 is connected to the sun gear 322 as the output element of the transmission 32, which enables the torsion spring 31 to It is sleeved on the outer circumference of the central shaft 33 and arranged coaxially with the central shaft 33, and the central shaft 33 can axially pass through the transmission 32, which saves the space of the inner cavity of the beam 10.

(Iii) The synchronous lifting device 40 is connected with the energy conversion device 30, which not only realizes the transmission between the rotation of the central shaft 33 and the telescopic movement of the legs 20, but also ensures that the legs 20 arranged in pairs can be telescoped synchronously.

(Iv) The outer short shaft 34 and the central shaft 33 can move a certain distance relative to each other in the axial direction, which facilitates the assembly and disassembly between the synchronous lifting device 40 and the energy conversion device 30. For storage and logistics cost considerations, manufacturers can separately produce and package the leg components, beam components, and table tops of the lifting platform, and then leave the overall assembly process of the lifting platform to consumers to complete.

Of course, the present invention is not limited to the above-mentioned embodiments, and those skilled in the art can make various modifications to the above-mentioned embodiments of the present invention under the teaching of the present invention without departing from the scope of the present invention. E.g:

(I) According to the lifting platform of the present invention, the pressure cylinder 50 may not be used to provide the second auxiliary power, that is, the installation of the pressure cylinder 50 may be omitted. When the pressure cylinder 50 is used to provide the second auxiliary power, a common pressure cylinder whose inner diameter of the cylinder 51 is equal in the axial direction may also be used.

(Ii) The lifting platform according to the present invention may have only one (rather than two) legs 20. At this time, the synchronous lifting device 40 connected to the legs 20 functions to transmit the rotation of the central shaft 33.

(Iii) The transmission 32 can also use a common gear transmission structure instead of a planetary gear transmission structure. For example, the transmission 32 has a transmission form in which a large gear meshes with a small gear, and the rotation axes of the large gear and the small gear are not the same In this case, the torsion spring 31 is connected to the large gear as the input element, and the central shaft 33 is connected to the small gear as the output element. Although the ordinary transmission may take up more space than the planetary gear transmission, the ordinary transmission has low requirements for the accuracy of components, more flexible transmission ratio settings, and convenient maintenance.

(Iv) The transmission chain 42 may also be a transmission belt, a transmission rope and other forms of endless transmission components.

However, the above are only examples of the present invention. When the scope of implementation of the present invention cannot be limited by this, all simple equivalent changes and modifications made in accordance with the scope of the patent application of the present invention and the content of the patent specification still belong to This invention patent covers the scope.

10: beam 20: Legs 21: First leg 22: second leg 30: Energy conversion device 31: Torsion Spring 32: Transmission 321: Planet Carrier 322: Sun Wheel 323: Planetary Wheel 324: Gear Ring 325: Shell 33: bottom bracket 34: outer short shaft 341: Spring 35: Clutch 351: Clutch switch 36: brake fork 37: Transmission components 371: Handle 372: Indicating Device 40: Synchronous lifting device 41: Support frame 42: drive chain 43: Sync Connector 44: Phase connector 441: connecting ring 50: pressure cylinder 51: Cylinder 52: Piston rod 53: Piston C1: The first chamber C2: second chamber

Other features and effects of the present invention will be clearly presented in the embodiments with reference to the drawings, in which: Fig. 1 is a schematic structural view of a main part of a lifting platform according to an embodiment of the present invention; Fig. 2 is a schematic structural diagram of an energy conversion device according to an embodiment of the present invention; 3 and 4 are schematic structural diagrams of a transmission according to an embodiment of the present invention; Figure 5 is a schematic structural diagram of a synchronous lifting device according to an embodiment of the present invention; Fig. 6 is a schematic structural view of a leg assembly according to an embodiment of the present invention; FIG. 7 is a schematic diagram of a partial structure of the assembly of the leg assembly and the beam assembly according to an embodiment of the present invention; and Fig. 8 is a schematic structural diagram of a pressure cylinder according to an embodiment of the present invention.

31: Torsion Spring

32: Transmission

33: bottom bracket

34: outer short shaft

35: Clutch

36: brake fork

37: Transmission components

Claims (10)

A lifting platform, which includes a platform, an energy conversion device and a leg assembly connected below the platform, wherein: The energy conversion device is used to convert elastic potential energy into auxiliary energy for lifting the table, and includes a torsion spring, a bottom bracket, and a transmission. The first end of the torsion spring is connected to the input element of the transmission. The bottom bracket is connected to the output element of the transmission, the rotation speed of the input element is less than the rotation speed of the output element, The leg assembly is connected with the central shaft, and during the forward or reverse rotation of the central shaft, the leg assembly is shortened or elongated to cause the table top to fall or rise. The lifting platform according to claim 1, wherein the transmission is a planetary gear transmission, which includes a ring gear, a sun gear, a number of planet wheels and a planet carrier; The ring gear is fixed, the planet carrier is connected to the torsion spring as the input element, and the sun gear is connected to the bottom shaft as the output element; The torsion spring is sleeved on the outer circumference of the central shaft and arranged coaxially with the central shaft. The elevator platform according to claim 1, wherein the transmission includes a large gear as the input element and a small gear as the output element, and rotation axes of the large gear and the small gear are not collinear. The lifting platform according to claim 1, wherein the lifting platform further includes a beam fixed to the platform, and the energy conversion device further includes a clutch, a brake fork, and a transmission assembly; The clutch is fixed to the beam, and the middle shaft passes through the clutch so as to rotate around its own axis; The brake fork is fixed to the bottom shaft, and the brake fork can be selectively locked or released by the clutch; when the brake fork is locked by the clutch, the bottom shaft cannot rotate; when the brake When the fork is released by the clutch, the middle shaft can rotate around its own axis; The transmission assembly is connected to the second end of the torsion spring, and the second end of the torsion spring can be rotated relative to the first end by operating the transmission assembly, so that the torsion spring can accumulate an elastic position. can. The lifting platform according to claim 1, wherein the leg assembly includes a first leg, a second leg, and a synchronous lifting device, and the first leg can approach or approach along the axial direction of the second leg. Away from the second leg, The synchronous lifting device includes: The support frame is a long strip; Two transmission wheels are arranged at the two ends of the support frame; An annular transmission member is tightly sleeved on the two transmission wheels by the two transmission wheels; and The synchronization connector is fixed to the annular transmission member; wherein, The bottom bracket is connected to the annular transmission member, the support frame is fixedly connected to the first leg, and the synchronization connector is fixedly connected to the second leg. The lifting platform according to claim 5, wherein the first leg is sleeved on the outer circumference of the second leg. The lifting platform according to claim 1, wherein the energy conversion device further comprises an outer stub shaft, and the outer stub shaft is movably nested and arranged at the end of the middle shaft and the middle shaft along the axial direction of each other . The lifting platform according to claim 7, wherein a spring is provided at the connection between the outer stub shaft and the central shaft, and the outer stub shaft can be close to the central shaft by pressing the spring. The lifting platform according to claim 5, wherein the leg assembly further includes a pressure cylinder, the cylinder of the pressure cylinder is fixedly connected to the support frame, and the piston rod of the pressure cylinder is connected to the second leg Fixed connection. The lifting platform according to claim 9, wherein the piston of the pressure cylinder partitions the cylinder into a first chamber and a second chamber, and the first chamber and the second chamber are in fluid communication , The piston rod extends out of the cylinder from the second chamber, The cylinder is divided into a first area and a second area in the axial direction, the second area is closer to the protruding end of the piston rod than the first area, In the first area, the inner diameter of the cylinder gradually becomes larger in the direction from the first chamber to the second chamber, and in the second area, the inner diameter of the cylinder Keep constant in the direction from the first chamber to the second chamber.

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