Lifting mechanism

The invention relates to a lifting mechanism which uses fluid as a damping medium to form a driving force. It has an outer tube, an inner tube and a spring using fluid as a damping medium to achieve a lifting effect, one end of the inner tube being inserted in the outer tube from one end of the outer tube, and one end of the spring being positioned in the outer tube; the other end of the spring penetrating through the inner tube and being connected with the inner tube.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Chinese Patent Application No. 201721923263.5 with a filing date of Dec. 29, 2017. The content of the aforementioned application, including any intervening amendments thereto, is incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a lifting mechanism which uses fluid as a damping medium to form a driving force.

BACKGROUND ART

A table which serves as an article for daily life is common in life, work and school learning. Along with improvement of living quality of people, requirements for functions of the table are more and more, for example, a requirement for the lifting function of the table is one of the requirements.

At present, lifting of most of tables is realized by gas spring mechanisms mounted on table legs, for example, an invention patent with the publication number being CN106308039A discloses a lifting device, and the lifting device comprises a spring which provides a holding force after lifting and uses fluid as a damping medium, a first sleeve and a second sleeve; one end of the spring is positioned in the first sleeve and is fixedly connected with one end of the first sleeve; one end of the second sleeve is inserted in the first sleeve from the other end of the first sleeve, the other end of the spring penetrates through the second sleeve, the spring and the second sleeve are fixedly connected, and a guiding assembly used for the second sleeve to lift is arranged on the first sleeve and/or the second sleeve; and the guiding assembly is a rolling friction assembly or a sliding friction assembly.

In the lifting device, when the guiding assemblies are rolling friction assemblies, the rolling friction assemblies are fixedly arranged on the first sleeve and the second sleeve separately, and when the spring lifts to push the second sleeve to lift, for the rolling friction assembly fixedly arranged on the first sleeve, the rolling element in the rolling friction assembly rotates under a friction force between the rolling element of the rolling friction assembly and the outer wall surface of the second sleeve. For the rolling friction assembly fixedly arranged at an end of the second sleeve, when the rolling friction assembly moves along with the second sleeve, the rolling element rotates under a friction force between the rolling element and the inner wall surface of the first sleeve.

However, because a mode of connecting the rolling friction assembly mounted at an end of the first sleeve with the first sleeve and a mode of connecting the rolling friction assembly mounted at an end of the second sleeve with the second sleeve are fixed connection modes, the friction force between the first sleeve and the second sleeve is large, and the large friction force has a hindering effect on lifting of the spring.

SUMMARY OF THE UTILITY MODEL

The invention aims to provide a lifting mechanism for reducing frictional resistance of an inner tube in lifting.

The technical solution for solving the technical problem is as follows:

The lifting mechanism comprises an outer tube, an inner tube and a spring using fluid as a damping medium to achieve a lifting effect, one end of the inner tube is inserted in the outer tube from one end of the outer tube, and one end of the spring is positioned in the outer tube; the other end of the spring penetrates through the inner tube and is connected with the inner tube, the lifting mechanism further comprises a floating guiding assembly, the floating guiding assembly is sleeved over the inner tube and is positioned between the outer tube and the inner tube, the surface of the floating guiding assembly is in contact with the outer wall surface of the inner tube and the inner wall surface of the outer tube separately, and when the inner tube lifts along with the spring, the floating guiding assembly axially moves relative to the inner tube and the outer tube under a friction force.

The invention has the advantages that movement of the floating guiding assembly is implemented by the friction force, therefore, the movement speed of the floating guiding assembly is smaller than the movement speed of the inner tube, and thus, a speed difference exists between the floating guiding assembly and the inner tube; because the outer tube is fixedly arranged, the floating guiding assembly moves relative to the outer tube; the floating guiding assembly axially moves relative to the inner tube and the outer tube under the friction force, thus, the guiding assembly further has an effect of reducing the friction force while guiding the inner tube, and thus, the inner tube lifts more smoothly.

DETAILED DESCRIPTION OF THE UTILITY MODEL

As shown inFIG. 1andFIG. 2, a lifting mechanism of the present utility model comprises an outer tube1, an inner tube2, a spring3using fluid as a damping medium to achieve a lifting effect, and a floating guiding assembly A, the various portions and the relationship between the portions will be described in detail below:

As shown inFIG. 1, one end of the inner tube2is inserted in the outer tube1from the other end of the outer tube1, one end of the spring3is positioned in the outer tube1, one end of the spring3penetrates through the inner tube2and is connected with the inner tube2, the spring3penetrates through the floating guiding assembly and then penetrates through the inner tube2, and the spring3and the inner tube2can be directly connected (such as welding or threaded connection or hinging), and can also be indirectly connected by an added connector (not shown in the figures). The spring3is a gas spring preferably. In one or more embodiments, the outer tube1is fixedly connected with a base4, therefore, when the lifting mechanism lifts, the outer tube1keeps still, and the inner tube2moves relative to the outer tube1.

As shown inFIG. 1andFIG. 2, the floating guiding assembly A is sleeved over the inner tube2and is positioned between the outer tube1and the inner tube2, the surface of the floating guiding assembly A is in contact with the outer wall surface of the inner tube2and the inner wall surface of the outer tube1separately, and when the inner tube2lifts along with the spring3, the floating guiding assembly axially moves relative to the inner tube and the outer tube under a friction force. The floating guiding assembly A is a rolling friction assembly preferably. When the inner tube2lifts, a friction force is generated between the inner tube2and the floating guiding assembly A, and by the friction force, the floating guiding assembly moves. Movement of the floating guiding assembly A is implemented by the friction force, therefore, the movement speed of the floating guiding assembly A is smaller than the movement speed of the inner tube2, and a speed difference exists between the floating guiding assembly and the inner tube2; and because the outer tube1is fixedly arranged, the floating guiding assembly A moves relative to the outer tube1.

As shown inFIG. 1andFIG. 2, the floating guiding assembly A is a rolling friction assembly preferably, the rolling friction assembly comprises a first retainer5and first rolling elements6, through holes are formed in the peripheral surface of the first retainer5, the first rolling elements6are spherical rolling elements preferably, the spherical rolling elements are steel balls preferably, and after the first rolling elements6are assembled in the through holes of the first retainer6, the surfaces of the first rolling elements6are in contact with the outer wall surface of the inner tube2and the inner wall surface of the outer tube1separately. The outer tube1and the inner tube2can be cylinders, and can also be prisms, in this embodiment, the outer tube1is a cylinder preferably, the inner tube2is a prism preferably, therefore, the cross section of the outer peripheral surface of the first retainer5is circular, the cross section of the inner peripheral surface of the first retainer5is polygonal, for example, the cross section of the inner peripheral surface of the first retainer5is rectangular, and thus, the shape of the first retainer5is separately matched with the shape of the outer tube1and the shape of the inner tube2.

As shown inFIG. 1andFIG. 2, a second guiding assembly B used for the inner tube2to lift is fixedly arranged at the end, which allows the inner tube to be inserted, of the outer tube1, the second guiding assembly B can be a rolling friction assembly, and can also be a sliding friction assembly, in this embodiment, the second guiding assembly B is the rolling friction assembly preferably, the second guiding assembly B consists of second rolling elements and a second retainer with through holes, a groove is formed in the inner peripheral surface of the second retainer, and the second rolling elements are positioned in the groove, and are in contact with the outer peripheral surface of the inner tube2. By the floating guiding assembly A and the second guiding assembly B, the inner tube2cannot shake in the lifting process, namely, the lifting process is more stable.

As shown inFIG. 3toFIG. 5, the cross section of the inner tube2is polygonal, preferably, the cross sections of the outer peripheral surface and the inner peripheral surface of the inner tube2are both orthohexagonal, for the floating guiding assembly A, the first retainer5is formed by splicing a plurality of splicing components5a, each splicing component5ais provided with a through hole for assembling the corresponding first rolling element6, in this embodiment, each first rolling element6is a cylindrical rolling element preferably, each cylindrical rolling element is a plastic or iron rolling element, one end of each splicing component5ais bent to form a first bent portion5bwhich is matched with the two adjacent surfaces on the inner tube2, the other end of each splicing component5ais bent to form a second bent portion5cwhich is matched with the two adjacent surfaces on the inner tube2, after the splicing components Sa are matched with the inner tube, the first bent portion5bof an optional splicing component5ais spliced with the second bent portion5cof the other adjacent splicing component5a.

As shown inFIG. 4andFIG. 5, according to a preferable structure mode for splicing between each first bent portion5band the corresponding second bent portion Sc, a notch5dis formed in each first bent portion5b, a protrusion5eis arranged at one end of each second bent portion5c, and the protrusion Se on each second bent portion5cis embedded in the corresponding notch5dto implement splicing.

As shown inFIG. 3toFIG. 5, for the second guiding assembly B, the second guiding assembly B is a plastic sleeve preferably, and the shape of the inner peripheral surface of the sleeve is matched with that of the outer peripheral surface of the inner tube2.

The rest structures are the same as the structures in embodiment 1, and the description thereof will not be repeated herein.

As shown inFIG. 6toFIG. 8, the floating guiding assembly A in this embodiment is a variant of the floating guiding assembly A in embodiment 2, a notch5dis formed in each first bent portion5b, a protrusion Se is arranged at one end of each second bent portion5c, and the protrusion5eon each second bent portion5cis fastened in the corresponding notch5dto implement splicing.

In addition, for the three foregoing embodiments, when the floating guiding assembly is a rolling friction assembly, the rolling friction assembly further comprises a sleeve7, as shown inFIG. 6toFIG. 8, the sleeve7is sleeved over the inner tube2, one end of the sleeve7extends towards the rising direction of the inner tube2, the other end of the sleeve7is fixedly connected with the first retainer5, and the sleeve7moves along with movement of the first retainer. After an end of the first retainer5is connected with the sleeve7, part of the sleeve7may be exposed to the outside of the outer tube1in the rising process of the sleeve7, when the part of the sleeve7is exposed to the outside of the outer tube1, three tubes including the outer tube1, the sleeve7and the inner tube2can be seen when the lifting mechanism of the present utility model is observed from the outside, and the inner tube2and the sleeve7lift. The structure is more attractive when seen from the outside, meanwhile, the sleeve7surrounds part of the inner tube2, some lubricating oil may be added in the outer tube1generally, the lubricating oil may be attached to the surface of the inner tube2, when the inner tube2lifts, the lubricating oil which is attached to the surface of the inner tube2lifts along with the inner tube2, and when the inner tube2extends to the outside of the outer tube1, the lubricating oil is prevented from being exposed in air owing to the surrounding effect of the inner tube2.

Moreover, a first guiding assembly8used for the sleeve to lift is fixedly arranged at the end, which extends towards the rising direction of the inner tube2, of the sleeve7, thus, the two ends of the sleeve7are guided and supported, and the sleeve7is more stable during lifting.

Moreover, a limiting component9which limits the floating guiding assembly against slipping off from the inner tube under the effect of gravity is arranged at the end, which is positioned in the outer tube, of the inner tube. The limiting component9can be fixedly arranged at the end of the inner tube2through a screw, and can also be integrally formed at the end of the inner tube2; and the limiting component9can be further arranged on the outer peripheral surface of the inner tube2, and when arranged on the outer peripheral surface, the limiting component9can be integrally formed with the inner tube, and can also be fastened by a screw.