Desk frame for a desk and such a desk
Patent Information
- Authority / Receiving Office
- US · United States
- Patent Type
- Applications(United States)
- Current Assignee / Owner
- ZHEJIANG JIECHANG LINEAR MOTION TECH
- Filing Date
- 2024-04-03
- Publication Date
- 2026-08-06
Smart Images
Figure US20260224021A1-D00000_ABST
Abstract
Description
FIELD
[0001] The subject matter described herein relates to furniture, and more particularly relates to a desk frame for a desk and such a desk.BACKGROUND
[0002] A conventional standing desk generally comprises a desktop and a desk frame, the desk frame comprising two leg assemblies and a telescopic crossbar connected therebetween. The telescopic crossbar extends and retracts to fit desktops of different lengths. However, with extension of the telescopic crossbar, the desk frame's support to a central portion of the desktop is likely diminished, causing a larger desk wobble.SUMMARY
[0003] To overcome a drawback of a conventional technology in which a supporting strength of a desk frame against a central portion of a desktop is diminished with extension of a telescopic crossbar, this disclosure describes a desk frame for a desk, according to which when the telescopic crossbar is in an extended state, a partial structure of the telescopic crossbar is lifted to press against the desktop, thereby providing an enhanced support to the desktop.
[0004] The present disclosure adopts a technical solution set forth below:
[0005] A desk frame for a desk, comprising two leg assemblies and a telescopic crossbar connected therebetween, an upper portion of each of the two leg assemblies being provided with a support portion configured to support a desktop, the support portions of the two leg assemblies being located in a same horizontal plane, the telescopic crossbar comprising a first crossbar and a second crossbar which are fitted one inside the other and are extendable / retractable relative to each other so that the telescopic crossbar is switchable between a retracted state and an extended state with a length greater than the retracted state; a partition groove is provided on the first crossbar along an extension / retraction direction of the first crossbar, the partition groove being configured to divide the first crossbar into an upper crossbar and a lower crossbar; when the telescopic crossbar is in the retracted state, an upper end surface of the upper crossbar and an upper end surface of the second crossbar are lower than or flush with the support portions; when the telescopic crossbar is in the extended state, a fitted section of the second crossbar is lifted by the lower crossbar so that the upper end surface of the second crossbar is higher than the support portions, and a fitted section of the upper crossbar is lifted by the second crossbar so that the upper end surface of the upper crossbar is higher than the support portions, whereby the desk frame, when being connected to the desktop, presses against the desktop to provide a support.
[0006] In the technical solution noted supra, when the telescopic crossbar is in the extended state, the fitted portion of the second crossbar is lifted by the first crossbar so that the upper end of the second crossbar is higher than the support portions; and the fitted section of the upper crossbar is lifted by the second crossbar so that the upper end surface of the upper crossbar is higher than the support portions; as such, the upper end surface of the second crossbar and the upper end surface of the upper crossbar, which are higher than the support portions, press against the lower end surface of the desktop to thereby provide a support to the desktop; in addition, the pressing force drives the lower crossbar to create a micro downward deformation, while the lower crossbar having a micro deformation further creates a corresponding counterforce against the desktop so that the supported section of the desktop and the first crossbar are not easily further deformed; in this way, the fitted position of the telescopic crossbar provides an enhanced support to the desktop. In the technical solution noted supra, since the upper end surface of the upper crossbar and the upper end surface of the second crossbar are lifted synchronously, the upper crossbar and the second crossbar support the desktop simultaneously from both sides of the desktop; in this way, the telescopic crossbar can offer a balanced support to the desktop in the length direction, which may enhance the support effect. When the telescopic crossbar is in the extended state, the fitted positions of the telescopic crossbar and the two support portions may create a four-point support to the desktop; with the additional two support points compared with the conventional two-point support created by the two support portions, the desk frame provides an enhanced support to the desktop; since the fitted positions of the telescopic crossbar are located between the two support portions while the support offered by the two support portions to the desktop is the weakest at the intermediate position between the two support portions, the fitted positions of the telescopic crossbar can provide an enhanced support to the desktop at the intermediate position, whereby the issue of insufficient support against the desktop at the intermediate position between the two support portions is overcome. Since the fitted positions of the telescopic crossbar are closer to the central portion of the desktop than the two support portions, this solution can provide an enhanced support to the central portion of the desktop. In the technical solution noted supra, with extension of the telescopic crossbar, the supporting strength offered by the desk frame against the central portion of the desktop is also enhanced, which may overcome the issues of conventional desks such as diminished support to the central portion of the desktop causing increased wobble of the desk with extension of the telescopic desk frame. Moreover, this technical solution offers a lower implementation cost and a simpler and stabler structure without increasing the difficulty in assembling the desk.
[0007] In some implementations, one end of the partition groove proximal to a free end of the first crossbar is open, and one end of the partition groove distal from the free end of the first crossbar is closed; a sliding shaft slidable along the partition groove is fixedly provided on the second crossbar, an upper side surface of the partition groove engages the sliding shaft; and while the fitted section of the second crossbar is lifted by the lower crossbar, the sliding shaft lifts the upper crossbar.
[0008] In some implementations, a width of the partition groove is progressively diminished from a closed end towards an open end thereof, and an upper end surface of the lower crossbar is inclined; a height of the upper end surface of the lower crossbar is progressively increased from one side proximal to a fixed end of the first crossbar towards opposite side thereof; the sliding shaft engaging the upper end surface of the lower crossbar; and when the telescopic crossbar switches from the retracted state to the extended state, the sliding shaft slides along the partition groove and is lifted by the upper end surface of the lower crossbar, so that the second crossbar is lifted, and the upper crossbar is lifted while the sliding shaft is lifted.
[0009] In the technical solutions noted supra, when the telescopic crossbar switches from the retracted state to the extended state, the sliding shaft slides along the partition groove; while the sliding shaft is sliding, it is lifted by the upper end surface of the lower crossbar, and the upper end surface of the second crossbar is synchronously lifted to thereby support the desktop; furthermore, since the width of the partition groove is progressively diminished from the closed end of the partition groove to the open end thereof, the lifted sliding shaft can further lift the upper crossbar via the lower end surface of the upper crossbar, whereby the upper end surface of the upper crossbar is higher than the support portions, which can impose a pressure against the desktop to thereby provide support thereto. The partition groove plays a plurality of roles: firstly, the upper end surface of the upper crossbar (i.e., the lower end surface of the partition groove) plays a role of guiding and supporting; when the telescopic crossbar switches from the retracted state to the extended state, the upper end surface of the second crossbar is lifted to press against the lower end surface of the desktop to thereby enhance support to the desktop; secondly, the partition groove divides the first crossbar into an upper crossbar which may be driven by the sliding shaft to be deformed upward to press against the desktop to thereby offer a support and a lower crossbar which may offer a support during the extension / retraction process; when the telescopic crossbar is in the extended state, the desktop at the side of the first crossbar can also be supported by the upper crossbar to thereby enhance the support effect at that side; thirdly, the telescopic crossbar may stop at any length position during extension so that the telescopic crossbar can be adapted to the length of the desktop; fourthly, since a plurality of purposes can be fulfilled by only providing one partition groove, no much difficulty is increased in manufacturing the first crossbar, so that the manufacturing cost can be reduced as much as possible. While the sliding shaft is sliding along the partition groove, the longer the telescopic crossbar extends, the higher the second crossbar and the upper crossbar are lifted, the greater the heights of the lifted second crossbar and upper crossbar over the support portions are, and the stronger the support offered by the second crossbar and the upper crossbar against the desktop is; in this way, with lengthwise extension of the telescopic crossbar, the support of the desk frame against the central portion of the desktop is also enhanced, thereby overcoming an issue of a conventional desk that with extension of the telescopic desk frame, the support against the central portion of the desktop is diminished causing an increased desk wobble.
[0010] In some implementations, the upper end surface of the upper crossbar is a first arcuate surface, a height of the first arcuate surface proximal to a side of the free end of the first crossbar being lower than a height of the first arcuate surface proximal to a side of the fixed end of the first crossbar; the upper side surface of the partition groove is a second arcuate surface adapted to the first arcuate surface, so that the upper crossbar has a consistent thickness at respective positions along its length direction.
[0011] In the technical solution noted supra, when the middle position of the upper crossbar is lifted by the sliding shaft, the upper crossbar and the sliding shaft form a simple lever construction, and the free end of the upper crossbar is also lifted, with a lifted height higher than that of the middle position of the upper crossbar; the first arcuate surface may offset the lifted height of the free end, which may prevent the free end of the upper crossbar from engaging the desktop, so that the supported position of the upper crossbar and the section from the supported position to the fixed end of the upper crossbar may press against the desktop to thereby form a support thereto, while the desktop near the free end of the upper crossbar is supported by the upper end surface of the second crossbar. The upper crossbar has a consistent thickness at respective positions in its length direction; the height of the upper end surface of the upper crossbar over the support portion and the height of the upper end surface of the second crossbar over the support portion are both determined by the inclination amount of the upper end surface of the lower crossbar; since their raised heights are equal, approximately identical support forces to the desktop may be created, unlikely causing mutual interference.
[0012] In some implementations, the first crossbar is provided thereon with a lifting bevel inclined along a length direction of the first crossbar, and the second crossbar is provided thereon with an engaging bevel inclined along a length direction of the second crossbar, the engaging bevel being adapted to and engaging the lifting bevel; when the telescopic crossbar is in the retracted state, a higher end of the lifting bevel engages a higher end of the engaging bevel, and a lower end of the lifting bevel engages a lower end of the engaging bevel; and when the telescopic crossbar switches from the retracted state to the extended state, the engaging bevel slides along the lifting bevel, driving the lower end of the second crossbar to move towards the higher end of the first crossbar, whereby the second crossbar is lifted.
[0013] In the technical solution noted supra, when the telescopic crossbar is in the retracted state, the higher end of the first crossbar engages the higher end of the second crossbar, while the lower end of the first crossbar engages the lower end of the second crossbar, whereby an avoidance role can be fulfilled, preventing the upper end surface of the second crossbar from being higher than the support portion; in the retracted state, the upper end of the first crossbar and the upper end surface of the second crossbar both engage the desktop to play a role of supporting. When the telescopic crossbar switches from the retracted state to the extended state, the engaging bevel slides along the lifting bevel; the longer the telescopic crossbar extends, the higher the second crossbar is lifted, the greater the height of the lifted second crossbar over the support portion is, and the stronger the support provided by the second crossbar to the desktop is; in this way, with extension of the telescopic crossbar, the support of the desk frame to the central portion of the desktop is also enhanced, thereby overcoming the issues of a conventional desk such as diminished supporting strength to the central portion of the desktop causing increased desk wobble with extension of the telescopic desk frame. In addition, during extension of the telescopic crossbar, when the telescopic crossbar extends to any length position, the second crossbar will be lifted to a corresponding height to thereby enhance support to the desktop. Therefore, within the adaptation capacity of the desk frame, the desk frame offers an adaptability to fit the length of the desktop while ensuring an enhanced support to the desktop.
[0014] In some implementations, the first crossbar is provided thereon with a lifting bevel inclined along a length direction of the first crossbar, and an engaging block is provided at a free end of the second crossbar, the engaging block engaging the lifting bevel so that when the telescopic crossbar switches from the retracted state to the extended state, the engaging block slides along the lifting bevel, whereby the second crossbar is lifted.
[0015] In the technical solution noted supra, when the telescopic crossbar is in the retracted state, the upper end surface of the first crossbar and the upper end surface of the second crossbar both engage the desktop to play a role of supporting. When the telescopic crossbar switches from the retracted state to the extended state, the engaging block slides along the lifting bevel; the longer the telescopic crossbar extends, the higher the engagement position between the lifting bevel and the engaging block is, the higher the engaging block and the second crossbar are lifted, and the stronger the support offered by the second crossbar against the desktop is; in this way, the support offered by the desk frame against the central portion of the desktop is also enhanced with extension of the telescopic crossbar, which may overcome the issues of a conventional desk such as diminished supporting strength against the central portion of the desktop causing increased desk wobble with extension of the telescopic desk frame. Moreover, during extension of the telescopic crossbar, when the telescopic crossbar extends to any length position, the second crossbar will be lifted to a corresponding height to thereby enhance support to the desktop. Therefore, within the adaptation capacity of the desk frame, the desk frame offers an adaptability to fit the length of the desktop while ensuring an enhanced support to the desktop.
[0016] In some implementations, the second crossbar is provided thereon with a lifting bevel inclined along a length direction of the second crossbar, and an engaging block is provided at the free end of the first crossbar, the engaging block engaging the lifting bevel, so that when the telescopic crossbar switches from the retracted state to the extended state, the engaging block slides along the lifting bevel, whereby the second crossbar is lifted.
[0017] In the technical solution noted supra, when the telescopic crossbar is in the retracted state, the upper end surface of the first crossbar and the upper end surface of the second crossbar both engage the desktop to play a role of supporting. When the telescopic crossbar switches from the retracted state to the extended state, the engaging block slides along the lifting bevel; the longer the telescopic crossbar extends, the lower the engagement position between the lifting bevel and the engaging block is, the higher the second crossbar is lifted, and the stronger the desktop is supported by the second crossbar; in this way, with extension of the telescopic crossbar, the supporting strength of the desk frame against the central portion of the desktop is also enhanced, which can solve issues of a conventional desk such as diminished supporting strength against the central portion of the desktop causing increased desk wobble with extension of the telescopic desk frame. Moreover, during extension of the telescopic crossbar, when the telescopic crossbar extends to any length position, the second crossbar is lifted to a corresponding height to provide an enhanced support to the desktop; therefore, within the adaptation capacity of the desk frame, the desk frame can be adapted to the length of the desktop while ensuring an enhanced support of the desk frame against the desktop.
[0018] In some implementations, the first crossbar is provided thereon with a plurality of bosses distributed in a stepwise profile along a length direction of the first crossbar, and the second crossbar is provided thereon with an engaging surface engaging upper end surfaces of the bosses and a plurality of avoidance slots configured to avoid the bosses, so that when the telescopic crossbar switches from the retracted state to the extended state, the engaging surface switches from engaging a lower boss to engaging a higher boss to thereby lift the second crossbar; when the telescopic crossbar is in the retracted state, the plurality of bosses are inserted into the plurality of avoidance slots, respectively; and when the telescopic crossbar is in the extended state, the engaging surface is supported on one of the bosses to thereby lift the second crossbar.
[0019] In the technical solution noted supra, when the telescopic crossbar is in the retracted state, the plurality of bosses are inserted into the plurality of avoidance slots, respectively, none of the plurality of bosses engaging the engaging surface; the upper end surface of the first crossbar and the upper end surface of the second crossbar both engaging the desktop to play a role of supporting. When the telescopic crossbar switches from a retracted state to a specific extended state, the engaging surface is supported on the corresponding boss to thereby lift the second crossbar; the remaining bosses are either rested in the avoidance slots or disposed beyond the projection scope of the second crossbar without interfering with the second crossbar. The longer the telescopic crossbar extends, the higher the upper end surface of the boss engaging the engaging surface is, the higher the second crossbar is lifted, and the stronger the support offered by the second crossbar against the desktop is, so that with extension of the telescopic crossbar, the support offered by the desk frame against the central portion of the desktop is also enhanced, thereby overcoming issues of a conventional desk such as diminished supporting strength against the central portion of the desktop causing increased desk wobble with extension of the telescopic desk frame.
[0020] In some implementations, the second crossbar is provided thereon with a plurality of bosses distributed in a stepwise profile along a length direction of the second crossbar, and the first crossbar is provided thereon with an engaging surface engaging upper end surfaces of the bosses and a plurality of avoidance slots configured to avoid the bosses, so that when the telescopic crossbar switches from the retracted state to the extended state, the engaging surface switches from engaging a lower boss to engaging a higher boss to thereby lift the second crossbar; when the telescopic crossbar is in the retracted state, the plurality of bosses are inserted in the plurality of avoidance slots, respectively; and when the telescopic crossbar is in the extended state, one of the bosses is supported on the engaging surface to thereby lift the second crossbar.
[0021] In the technical solution noted supra, when the telescopic crossbar is in the retracted state, the plurality of bosses are inserted into the plurality of avoidance slots, respectively, none of the plurality of bosses engaging the engaging surface; the upper end surface of the first crossbar and the upper end surface of the second crossbar both engage the desktop to play a role of supporting. When the telescopic crossbar switches from the retracted state to a specific extended state, the engaging surface is supported on the corresponding boss, whereby the second crossbar is lifted; the remaining bosses are either rested in the avoidance slots or disposed beyond the projection scope of the first crossbar, without interfering with the first crossbar. The longer the telescopic crossbar extends, the lower the height of the lower end surface of the boss engaging the engaging surface is, the higher the second crossbar is lifted, and the stronger the support offered by the second crossbar against the desktop is; in this way, with extension of the telescopic crossbar, the support of the desk frame against the central portion of the desktop is also enhanced, which may overcome issues of a conventional desk such as diminished supporting strength against the central portion of the desktop causing increased desk wobble with extension of the telescopic desk frame.
[0022] In some implementations, two telescopic crossbars are provided and connected between the two leg assemblies in a side-by-side manner, with one end of each of the two first crossbars being fixed to one of the leg assemblies, one end of each of the two second crossbars being fixed to the other one of the leg assemblies; or, one end of each of the two first crossbars is fixed to the two leg assemblies, respectively; one end of each of the two second crossbars is fixed to the two leg assemblies, respectively.
[0023] In the first option noted supra, by arranging the two telescopic crossbars in a side-by-side manner, an enhanced support effect can be achieved. In the second option noted supra, the lifted second crossbars can support the desktop; by arranging the two second crossbars in a diagonal manner, a more uniform support to the desktop is achieved, which may prevent occurrence of a circumstance in which if the two second crossbars support the desktop only from one side, the other side of the desktop not supported by the second crossbars receives an insufficient supporting strength.
[0024] A desk comprises a desktop, wherein the desk further comprises a desk frame for a desk noted supra, leg assemblies are disposed under the desktop, each of the leg assemblies comprising a leg and a support frame fixed to an upper end of the leg, the support portion being disposed at the support frame, the support frame supporting the desktop via the support portion.BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 is a structural schematic diagram of a desk frame according to some implementations of this disclosure;
[0026] FIG. 2 is a first structural schematic diagram of a telescopic crossbar according to some implementations of this disclosure;
[0027] FIG. 3 is a second structural schematic diagram of a telescopic crossbar according to some implementations of this disclosure;
[0028] FIG. 4 is a structural schematic diagram of a desk according to some implementations of this disclosure;
[0029] FIG. 5 is a first local structural schematic diagram of a telescopic crossbar according to some implementations of this disclosure;
[0030] FIG. 6 is a second local structural schematic diagram of a telescopic crossbar according to some implementations of this disclosure;
[0031] FIG. 7 is a third local structural schematic diagram of a telescopic crossbar according to some implementations of this disclosure;
[0032] FIG. 8 is a first sectional view of a telescopic crossbar according to some implementations of this disclosure;
[0033] FIG. 9 is a local enlarged view of part A in FIG. 8;
[0034] FIG. 10 is a second sectional view of a telescopic crossbar according to some implementations of this disclosure;
[0035] FIG. 11 is a Local Enlarged View of Part B in FIG. 10;
[0036] FIG. 12 is a third structural schematic diagram of a telescopic crossbar according to some implementations of this disclosure;
[0037] FIG. 13 is a fourth local structural schematic diagram of a telescopic crossbar according to some implementations of this disclosure;
[0038] FIG. 14 is a fifth local structural schematic diagram of a telescopic crossbar according to some implementations of this disclosure.
[0039] In the drawings: 1—first crossbar; 1.1—recess; 1.2—first flange; 1.3—partition groove; 1.4—upper crossbar; 1.5—lower crossbar; 1.6—first arcuate surface; 1.7—second arcuate surface; 2—second crossbar; 2.1—second flange; 2.2—sliding shaft; 3—lifting bevel; 4—engaging bevel; 5—engaging block; 6—boss; 7—engaging surface; 8—avoidance slot; 100—telescopic crossbar; 200—leg assembly; 210—leg; 220—support frame; 221—support portion; 300—desktop.DETAILED DESCRIPTION OF EMBODIMENTS
[0040] Hereinafter, this disclosure will be further described through specific implementations with reference to the accompanying drawings.First Implementation
[0041] As illustrated in FIGS. 1-4 , a desk frame for a desk comprises two leg assemblies 200 and a telescopic crossbar 100 connected therebetween, a support portion 221 configured to support the desktop being provided at an upper portion of each of the two leg assemblies 200, the support portions 221 of the two leg assemblies 200 being disposed in a same horizontal plane, the telescopic crossbar 100 comprising a first crossbar 1 and a second crossbar 2 which are fitted one inside the other and extendable / retractable relative to each other so that the telescopic crossbar 100 is switchable between a retracted state and an extended state with a length greater than the retracted state; when the telescopic crossbar 100 is in the retracted state, an upper end surface of the first crossbar 1 and an upper end surface of the second crossbar 2 are lower than or flush with the support portions 221, and when the telescopic crossbar 100 is in the extended state, a fitted section of the second crossbar 2 is lifted by the first crossbar 1 so that the upper end surface of the second crossbar 2 is higher than the support portions 221, which imposes a pressure against the desktop to thereby provide support when connecting the desk frame to the desktop.
[0042] In the technical solution described supra, one end of the first crossbar 1 is fixed to one of the leg assemblies 200, one end of the second crossbar 2 is fixed to the other one of the leg assemblies 200, and the telescopic crossbar 100 is disposed relatively close to a central portion of the desktop 300. When the telescopic crossbar 100 is in the extended state, the fitted portion of the second crossbar 2 is lifted by the first crossbar 1 so that the upper end of the second crossbar 2 is higher than the support portion 221; as such, the upper end surface of the second crossbar 2 higher than the support portion 221 presses against the lower end surface of the desktop 300 to thereby offer a support to the desktop 300; in addition, the pressing force drives the first crossbar 1 to create a micro downward deformation, while the first crossbar 1 having a micro deformation further creates a corresponding counterforce against the desktop 300 so that the supported section of the desktop 300 and the first crossbar 1 are not easily further deformed; in this way, the fitted position of the telescopic crossbar 100 provides an enhanced support to the desktop 300. When the telescopic crossbar 100 is in the extended state, the fitted position of the telescopic crossbar 100 and the two support portions 221 may create a three-point support to the desktop 300, which provides an additional support point compared with the conventional two-point support created by the two support portions 221, whereby the desk frame offers an enhanced support to the desktop 300; in addition, since the fitted position of the telescopic crossbar 100 is disposed between the two support portions 221 while the support offered by the two support portions 221 against the desktop 300 is the weakest at the intermediate position between the two support portions 221, the fitted position of the telescopic crossbar 100 may provide an enhanced support to the desktop 300 at that position, thereby overcoming the issue of insufficient support to the desktop at the intermediate position between the two support portions 221. Since the fitted position of the telescopic crossbar 100 is closer to the central portion of the desktop 300 than the two support portions 221, this solution can contribute an increased support to the central portion of the desktop 300. In the technical solution described supra, with extension of the telescopic crossbar 100, the supporting strength offered by the desk frame against the central portion of the desktop 300 is also enhanced, which may overcome the issues of conventional desks such as diminished support to the central portion of the desktop causing increased desk wobble with extension of the telescopic desk frame. Moreover, this technical solution offers a lower implementation cost and a simpler and stabler structure without increasing the difficulty in assembling the desk.
[0043] As illustrated in FIGS. 12 and 13, a partition groove 1.3 is provided on the first crossbar 1 along a telescoping direction thereof, the partition groove 1.3 being configured to partition the first crossbar 1 into an upper crossbar 1.4 and a lower crossbar 1.5, one end of the partition groove 1.3 proximal to a free end of the first crossbar 1 being open, one end of the partition groove 1.3 distal from the free end of the first crossbar 1 being closed; a sliding shaft 2.2 slidable along the partition groove 1.3 is fixedly provided on the second crossbar 2, an upper side surface of the partition groove 1.3 engaging the sliding shaft 2.2; the fitted section of the second crossbar 2 is lifted by the lower crossbar 1.5, and the sliding shaft 2.2 slides along the partition groove 1.3 while lifting the upper crossbar 1.4, whereby the upper end surface of the upper crossbar 1.4 is higher than the support portion 221.
[0044] In the technical solution noted supra, when the telescopic crossbar is in the extended state, the fitted section of the second crossbar is lifted by the first crossbar so that the upper end of the second crossbar is higher than the support portions, and the fitted section of the upper crossbar is lifted by the second crossbar so that the upper end surface of the upper crossbar is higher than the support portions; the upper end surface of the second crossbar and the upper end surface of the upper crossbar, which are higher than the support portions, press against the lower end surface of the desktop to thereby provide a support to the desktop; since the upper end surface of the upper crossbar and the upper end surface of the second crossbar are lifted synchronously, the upper crossbar and the second crossbar support the desktop simultaneously from both sides of the desktop; in this way, the telescopic crossbar can offer a balanced support to the desktop in the length direction, which may enhance the support effect. When the telescopic crossbar is in the extended state, the fitted positions of the telescopic crossbar and the two support portions may create a four-point support to the desktop; with the additional two support points compared with the conventional two-point support created by the two support portions, the desk frame provides an enhanced support to the desktop; since the fitted positions of the telescopic crossbar are located between the two support portions while the support offered by the two support portions to the desktop is the weakest at the intermediate position between the two support portions, the fitted positions of the telescopic crossbar can provide an enhanced support to the desktop at the intermediate position, whereby the issue of insufficient support against the desktop at the intermediate position between the two support portions is overcome. Since the fitted positions of the telescopic crossbar are closer to the central portion of the desktop than the two support portions, this solution can provide an enhanced support to the central portion of the desktop.
[0045] In some examples, a recess 1.1 with an open upper portion is provided on the first crossbar 1 along its length direction so that the second crossbar 2 can be accommodated in the recess 1.1. This structure enables the first crossbar 1 and the second crossbar 2 to partially overlap in the height direction, thereby shrinking the height dimension of the telescopic crossbar 100; moreover, since the second crossbar 2 can be accommodated in the recess 1.1, the first crossbar 1 can provide an enhanced support to the second crossbar 2.
[0046] In one implementation, an upper end of the first crossbar 1 extends horizontally to form a first flange 1.2, and an upper end of the second crossbar 2 extends horizontally to form a second flange 2.1; when the telescopic crossbar 100 is in the retracted state, an upper surface of the first flange 1.2 and an upper surface of the second flange 2.1 are flush with the support portions 221; when the telescopic crossbar 100 is in the extended state, the second flange 2.1 is lifted by the first crossbar 1 so that the upper end of the second flange 2.1 is higher than the first flange 1.2.
[0047] In the technical solution noted supra, the first flange 1.2 and the second flange 2.1 may increase an engagement area between the telescopic crossbar 100 and the desktop 300, which reduces damages to the lower end surface of the desktop 300 due to the support action, reduces deformation of the lower end surface of the desktop 300, and increases the support effect; in addition, this structure may contribute an enhanced strength to the first crossbar 1 and the second crossbar 2, further enhancing the support effect.
[0048] In some examples, the first flange 1.2 and the second flange 2.1 are disposed at both sides of the telescopic crossbar 100 in the width direction, respectively. This structure may enhance support stability; in addition, since the two flanges are located at both sides of the telescopic crossbar 100, they do not interfere with each other.
[0049] In some examples, the first flange 1.2 and the second flange 2.1 both extend towards the outer sides of the recess 1.1, respectively.
[0050] In some examples, scales are set on the first crossbar 1 and the second crossbar 2, so that the length dimension of the desk frame can be rendered more intuitive.
[0051] It may be understood that, in one implementation, the telescopic crossbar 100 is connected between the leg assemblies in an ipsilateral, single-sided manner, which facilitates connecting the telescopic crossbar 100 to the leg assemblies 200.
[0052] It may be understood that, in another implementation, the telescopic crossbar is connected between the leg assemblies in a diagonal, single-sided manner. By connecting the telescopic crossbar diagonally between the leg assemblies, the telescopic crossbar is disposed as close to the central position of the desktop as possible, thereby enhancing the support effect.
[0053] It may be understood that, in a further implementation, two telescopic crossbars are provided and connected between the two leg assemblies in a side-by-side manner, with one end of each of the two first crossbars being fixed to one of the leg assemblies, one end of each of the two second crossbars being fixed to the other one of the leg assemblies. By connecting the two telescopic crossbars in a side-by-side manner, an enhanced support is achieved.
[0054] It may be understood that, in a still further implementation, one end of each of the two first crossbars is fixed to the two leg assemblies, respectively; one end of each of the two second crossbars is fixed to the two leg assemblies, respectively. In this technical solution, the lifted second crossbars can support the desktop; by arranging the two second crossbars in a diagonal manner, a more uniform support to the desktop is achieved, which may prevent occurrence of a circumstance that if the two second crossbars support the desktop only from one side, the other side of the desktop not supported by the second crossbars would receive an insufficient supporting strength.
[0055] It may be understood that, in one implementation, the telescopic crossbar comprises one first crossbar and one second crossbar.
[0056] It may be understood that, in another implementation, the telescopic crossbar comprises two first crossbars and one second crossbar, the two first crossbars being connected to the two leg assemblies, respectively, while two ends of the second crossbar are connected to the two first crossbars, respectively.Second Implementation
[0057] As illustrated in FIGS. 12 and 14, on the basis of the first implementation, a width of the partition groove 1.3 is progressively diminished from the closed end to the open end of the partition groove 1.3; the upper end surface of the lower crossbar 1.5 is inclined so that a height of the upper end surface of the lower crossbar 1.5 progressively increases from one side proximal to the fixed end of the first crossbar 1 towards the opposite side; and the sliding shaft 2.2 engages the upper end surface of the lower crossbar 1.5. When the telescopic crossbar 100 switches from the retracted state to the extended state, the sliding shaft 2.2 slides along the partition groove 1.3 and is lifted by the upper end surface of the lower crossbar 1.5, whereby the second crossbar 2 is lifted; while the sliding shaft 2.2 is lifted, the upper crossbar 1.4 is also lifted. In this implementation, the upper side surface of the partition groove 1.3 is equivalent to the upper end surface of the lower crossbar 1.5.
[0058] In the technical solution described supra, when the telescopic crossbar 100 switches from the retracted state to the extended state, the sliding shaft 2.2 slides along the partition groove 1.3; while the sliding shaft 2.2 is sliding, it is lifted by the upper end surface of the lower crossbar 1.5, and the upper end surface of the second crossbar 2 is synchronously lifted to thereby support the desktop 300; furthermore, since the width of the partition groove 1.3 is progressively diminished from the closed end of the partition groove 1.3 towards the open end thereof, the lifted sliding shaft 2.2 can further lift the upper crossbar 1.4 via the lower end surface of the upper crossbar 1.4, whereby the upper end surface of the upper crossbar 1.4 is higher than the support portions 221, which can impose a pressure against the desktop 300 to thereby provide a support thereto. The partition groove 1.3 plays a plurality of roles: firstly, the upper end surface of the upper crossbar 1.4 (i.e., the lower end surface of the partition groove 1.3) plays a role of guiding and supporting; when the telescopic crossbar 100 switches from the retracted state to the extended state, the upper end surface of the second crossbar 2 is lifted to press against the lower end surface of the desktop 300 to thereby enhance support to the desktop 300; secondly, the partition groove 1.3 divides the first crossbar 1 into an upper crossbar 1.4 which may be driven by the sliding shaft 2.2 to be deformed upward to press against the desktop 300 to thereby offer a support and a lower crossbar 1.5 which may offer a support during the extension / retraction process; when the telescopic crossbar 100 is in the extended state, the desktop 300 at the side of the first crossbar 1 can also be supported by the upper crossbar 1.4 to thereby enhance the support effect at that side; thirdly, the telescopic crossbar 100 may stop at any length position during extension so that the telescopic crossbar 100 can be adapted to the length of the desktop 300; fourthly, since a plurality of purposes can be fulfilled by only providing one partition groove 1.3, no much difficulty is increased in manufacturing the first crossbar 1, so that the manufacturing cost can be reduced as much as possible. While the sliding shaft 2.2 is sliding along the partition groove 1.3, the longer the telescopic crossbar 100 extends, the higher the second crossbar 2 and the upper crossbar 1.4 are lifted, the greater the heights of the lifted second crossbar 2 and the upper crossbar 1.4 over the support portion 221 are, and the stronger the support offered by the second crossbar 2 and the upper crossbar 1.4 against the desktop 300 is; in this way, with lengthwise extension of the telescopic crossbar 100, the support of the desk frame against the central portion of the desktop 300 is also enhanced, thereby overcoming an issue of a conventional desk such as diminished support against the central portion of the desktop causing an increased desk wobble with extension of the telescopic desk frame. Moreover, during extension of the telescopic crossbar 100, when the telescopic crossbar 100 extends to any length position, the second crossbar 2 will be lifted to a corresponding height, whereby the support to the desktop 300 is enhanced; as such, within the adaptation capacity of the desk frame, the desk frame is adaptable to fit the length of the desktop 300 while ensuring an enhanced support to the desktop 300.Third Implementation
[0059] As illustrated in FIGS. 13 and 14, on the basis of the first implementation or the second implementation, the upper surface of the upper crossbar 1.4 is a first arcuate surface 1.6, a height of the first arcuate surface 1.6 proximal to the side of the free end of the first crossbar 1 being lower than a height of the first arcuate surface 1.6 proximal to the side of the fixed end of the first crossbar 1; a lower end surface of the upper crossbar 1.4 is a second arcuate surface 1.7 adapted to the first arcuate surface 1.6 so that the upper crossbar 1.4 has a consistent thickness at respective positions in its length direction. An axis of the first arcuate surface 1.6 and an axis of the second arcuate surface 1.7 are located below the upper crossbar 1.4.
[0060] In the technical solution described supra, when the middle position of the upper crossbar 1.4 is lifted by the sliding shaft 2.2, the upper crossbar 1.4 and the sliding shaft 2.2 form a simple lever construction, and the free end of the upper crossbar 1.4 is also lifted, with a lifted height higher than that of the middle position of the upper crossbar 1.4; the first arcuate surface 1.6 may offset the lifted height of the free end, which may prevent the free end of the upper crossbar 1.4 from engaging the desktop 300, so that the supported position of the upper crossbar 1.4 and the section from the supported position to the fixed end of the upper crossbar 1.4 may press against the desktop 300 to thereby form a support thereto, while the desktop 300 near the free end of the upper crossbar 1.4 is supported by the upper end surface of the second crossbar 2. The upper crossbar has a consistent thickness at respective positions in its length direction; the height of the upper end surface of the upper crossbar over the support portion and the height of the upper end surface of the second crossbar over the support portion are both determined by the inclination amount of the upper end surface of the lower crossbar; since their raised heights are equal, approximately identical support forces may be formed to the desktop, unlikely causing mutual interference.Fourth Implementation
[0061] As illustrated in FIGS. 1, 2, 3, 4, and 5, on the basis of the first implementation, the lower crossbar 1.5 is provided thereon with a lifting bevel 3 inclined along the length direction of the lower crossbar 1.5, and the second crossbar 2 is provided thereon with an engaging bevel 4 inclined along a length direction of the second crossbar 2, the lifting bevel 3 and the engaging bevel 4 being inclined in a same direction; the lifting bevel 3 is disposed below the engaging bevel 4, the engaging bevel 4 being adapted to and engaging the lifting bevel 3; when the telescopic crossbar 100 is in the retracted state, a higher end of the lifting bevel 3 engages a higher end of the engaging bevel 4, while a lower end of the lifting bevel 3 engages a lower end of the engaging bevel 4; when the telescopic crossbar 100 switches from the retracted state to the extended state, the engaging bevel 4 slides along the lifting bevel 3 so that the lower end of the second crossbar 2 moves towards the higher end of the first crossbar 1 so that they press against each other to lift the second crossbar 2.
[0062] In the technical solution described supra, the lower end of the lifting bevel 3 refers to the end of the lifting bevel 3 which is relatively low in height, and the higher end of the lifting bevel 3 refers to the end of the lifting bevel 3 which is relatively high in height; and the lower end of the engaging bevel 4 refers to the end of the engaging bevel 4 which is relatively low in height, and the higher end of the engaging bevel 4 refers to the end of the engaging bevel 4 which is relatively high in height. When the telescopic crossbar 100 is in the retracted state, the higher end of the first crossbar 1 engages the higher end of the second crossbar 2, while the lower end of the first crossbar 1 engages the lower end of the second crossbar 2, whereby an avoidance role can be fulfilled, preventing the upper end surface of the second crossbar 2 from being higher than the support portion 221; in the retracted state, the upper end of the first crossbar 1 and the upper end surface of the second crossbar 2 both engage the desktop 300 to play a role of supporting. When the telescopic crossbar 100 switches from the retracted state to the extended state, the engaging bevel 4 slides along the lifting bevel 3; the longer the telescopic crossbar 100 extends, the higher the second crossbar 2 is lifted, the greater the height of the lifted second crossbar 2 over the support portion 221 is, and the stronger the support provided by the second crossbar 2 to the desktop 300 is; in this way, with extension of the telescopic crossbar 100, the support of the desk frame to the central portion of the desktop 300 is also enhanced, thereby overcoming the issues of a conventional desk such as diminished supporting strength to the central portion of the desktop causing increased desk wobble with extension of the telescopic desk frame. In addition, during extension of the telescopic crossbar 100, when the telescopic crossbar 100 extends to any length position, the second crossbar 2 will be lifted to a corresponding height to thereby enhance support to the desktop 300. Therefore, within the adaptation capacity of the desk frame, the desk frame offers an adaptability to fit the length of the desktop 300 while ensuring an enhanced support to the desktop 300.Fifth Implementation
[0063] As illustrated in FIGS. 1, 2, 3, 4, and 6, on the basis of the first implementation, the lower crossbar 1.5 is provided thereon with a lifting bevel 3 inclined along its length direction, and an engaging block 5 is provided at the free end of the second crossbar 2, the engaging block 5 engaging the lifting bevel 3 so that when the telescopic crossbar 100 switches from the retracted state to the extended state, the engaging block 5 slides along the lifting bevel 3 with the second crossbar 2 lifted.
[0064] In the technical solution described supra, the free end of the second crossbar 2 refers to the end of the second crossbar 2 not fixed to the leg assembly 200. The engaging block 5 is disposed above the lifting bevel 3; when the telescopic crossbar 100 is in the retracted state, the upper end surface of the first crossbar 1 and the upper end surface of the second crossbar 2 both engage the desktop 300 to play a role of supporting. When the telescopic crossbar 100 switches from the retracted state to the extended state, the engaging block 5 slides along the lifting bevel 3; the longer the telescopic crossbar 100 extends, the higher the engagement position between the lifting bevel 3 and the engaging block 5 is, the higher the engaging block 5 and the second crossbar 2 are lifted, and the stronger the support offered by the second crossbar 2 against the desktop 300 is; in this way, the support offered by the desk frame against the central portion of the desktop 300 is enhanced with extension of the telescopic crossbar 100, which may overcome the issues of a conventional desk such as diminished supporting strength against the central portion of the desktop causing increased desk wobble with extension of the telescopic desk frame. Moreover, during extension of the telescopic crossbar 100, the telescopic crossbar 100 may stop at any length position so as to be adapted to the length of the desktop 300.
[0065] In some examples, an avoidance recess is provided on the second crossbar 2 to prevent other components than the engaging block 5 from interfering with the first crossbar 1 when the second crossbar 2 slides relative to the first crossbar 1.Sixth Implementation
[0066] As illustrated in FIGS. 1, 2, 3, 4, and 7, on the basis of the first implementation, the second crossbar 2 is provided thereon with a lifting bevel 3 inclined along its length direction, and an engaging block 5 is provided at the free end of the lower crossbar 1.5, the engaging block 5 engaging the lifting bevel 3 so that when the telescopic crossbar 100 switches from the retracted state to the extended state, the engaging block 5 slides along the lifting bevel 3 with the second crossbar 2 being lifted.
[0067] In the technical solution described supra, the free end of the first crossbar 1 refers to the end of the first crossbar 1 not fixed to the leg assembly 200. When the telescopic crossbar 100 is in the retracted state, the upper end surface of the first crossbar 1 and the upper end surface of the second crossbar 2 both engage the desktop 300 to play a role of supporting. When the telescopic crossbar 100 switches from the retracted state to the extended state, the engaging block 5 slides along the lifting bevel 3; the longer the telescopic crossbar 100 extends, the lower the engagement position between the lifting bevel 3 and the engaging block 5 is, the higher the second crossbar 2 is lifted, and the stronger the desktop 300 is supported by the second crossbar 2; in this way, with extension of the telescopic crossbar 100, the supporting strength of the desk frame against the central portion of the desktop 300 is also enhanced, which can solve issues of a conventional desk such as diminished supporting strength against the central portion of the desktop causing increased desk wobble with extension of the telescopic desk frame. Moreover, during extension of the telescopic crossbar 100, when the telescopic crossbar 100 extends to any length position, the second crossbar 2 is lifted to a corresponding height to provide an enhanced support to the desktop 300; therefore, within the adaptation capacity of the desk frame, the desk frame can be adapted to the length of the desktop 300 while ensuring an enhanced support of the desk frame against the desktop 300.
[0068] In some examples, an avoidance recess is provided on the first crossbar 1, which may prevent other components than the engaging block 5 from interfering with the second crossbar 2 when the first crossbar 1 slides relative to the second crossbar 2.Seventh Implementation
[0069] As illustrated in FIGS. 1 to 4, and 8 to 11, on the basis of the first implementation, the lower crossbar 1.5 is provided thereon with a plurality of bosses 6 distributed in a stepwise profile along its length direction, and the second crossbar 2 is provided thereon with an engaging surface 7 engaging the upper end surfaces of the bosses 6 and a plurality of avoidance slots 8 configured to avoid the bosses 6, so that when the telescopic crossbar 100 switches from the retracted state to the extended state, the engaging surface 7 switches from engaging a lower boss 6 to engaging a higher boss 6 to thereby lift the second crossbar 2. When the telescopic crossbar 100 is in the retracted state, the plurality of bosses 6 are inserted into the plurality of corresponding avoidance slots 8, respectively; when the telescopic crossbar 100 is in the extended state, the engaging surface 7 is supported on one of the bosses 6 to lift the second crossbar 2.
[0070] In the technical solution described supra, the free end of the first crossbar 1 refers to the end of the first crossbar 1 not fixed to the leg assembly 200. When the telescopic crossbar 100 is in the retracted state, the plurality of bosses 6 are inserted into the plurality of avoidance slots 8, respectively, none of the plurality of bosses 6 engaging the engaging surface 7; the upper end surface of the first crossbar 1 and the upper end surface of the second crossbar 2 both engaging the desktop 300 to play a role of supporting. When the telescopic crossbar 100 switches from a retracted state to a specific extended state, the engaging surface 7 is supported on the corresponding boss 6 to thereby lift the second crossbar 2; the remaining bosses 6 are either rested in the avoidance slots 8 or disposed beyond the projection scope of the second crossbar 2 without interfering with the second crossbar 2. The longer the telescopic crossbar 100 extends, the higher the upper end surface of the boss 6 engaging the engaging surface 7 is, the higher the second crossbar 2 is lifted, and the stronger the support offered by the second crossbar 2 against the desktop 300 is, so that with extension of the telescopic crossbar 100, the support offered by the desk frame against the central portion of the desktop 300 is also enhanced, thereby overcoming issues of a conventional desk such as diminished supporting strength against the central portion of the desktop causing increased desk wobble with extension of the telescopic desk frame.
[0071] It may be understood that, in one implementation, every two neighboring bosses 6 are spaced uniformly to facilitate the bosses 6 to access the corresponding avoidance slots 8 to achieve avoidance.
[0072] It may be understood that, in another implementation, every two neighboring bosses 6 are non-uniformly spaced; however, when one of the bosses 6 engages the engaging surface 7, the avoidance slots 8 arranged at positions of the second crossbar 2 corresponding to the remaining bosses 6 under the second crossbar 2 serve to avoid the bosses 6.
[0073] It may be understood that, in another implementation, every two neighboring bosses 6 are non-uniformly spaced; however, the avoidance slots 8 are elongated slots arranged in the length direction of the second crossbar 2; when one of the bosses 6 engages the engaging surface 7, the remaining bosses 6 under the second crossbar 2 are all rested in the avoidance slots 8.Eighth Implementation
[0074] On the basis of the first implementation, the second crossbar is provided thereon with a plurality of bosses distributed in a stepwise profile along its length direction, and the lower crossbar is provided thereon with an engaging surface engaging the upper end surfaces of the bosses and a plurality of avoidance slots configured to avoid the bosses, so that when the telescopic crossbar switches from the retracted state to the extended state, the engaging surface switches from engaging a lower boss to engaging a higher boss to thereby lift the second crossbar. When the telescopic crossbar is in the retracted state, the plurality of bosses are inserted into the plurality of corresponding avoidance slots, respectively; and when the telescopic crossbar is in the extended state, one of the bosses is supported on the engaging surface to lift the second crossbar.
[0075] In the technical solution descried supra, when the telescopic crossbar is in the retracted state, the plurality of bosses are inserted into the plurality of avoidance slots, respectively, none of the plurality of bosses engaging the engaging surface; the upper end surface of the first crossbar and the upper end surface of the second crossbar both engage the desktop to play a role of supporting. When the telescopic crossbar switches from the retracted state to a specific extended state, the engaging surface is supported on the corresponding boss, whereby the second crossbar is lifted; the remaining bosses are either rested in the avoidance slots or disposed beyond the projection scope of the first crossbar, without interfering with the first crossbar. The longer the telescopic crossbar extends, the lower the height of the lower end surface of the boss engaging the engaging surface is, the higher the second crossbar is lifted, and the stronger the support offered by the second crossbar against the desktop is; in this way, with extension of the telescopic crossbar, the support of the desk frame against the central portion of the desktop is also enhanced, which may overcome issues of a conventional desk such as diminished supporting strength against the central portion of the desktop causing increased desk wobble with extension of the telescopic desk frame.Ninth Implementation
[0076] As illustrated in FIGS. 1 to 4, a desk comprises a desktop 300 and the desk frame for a desk as described in the aforementioned implementations, the leg assemblies 200 being arranged under the desktop 300, each of the leg assemblies 200 comprising a leg 210 and a support frame 220 fixed to an upper end of the leg 210, the support portion 221 being disposed at the support frame 220, the support frame 220 supporting the desktop 300 via the support portion 221.
[0077] This disclosure achieves the following benefits: simpler structure, lower manufacturing cost, easy and efficient assembly and disassembly, no damages caused to the outer surface of the spring, and adaptability to assembly and disassembly of energy-storage springs of different sizes.
Claims
1. A desk frame for a desk, comprising two leg assemblies and a telescopic crossbar connected therebetween, an upper portion of each of the two leg assemblies being provided with a support portion configured to support a desktop, the support portions of the two leg assemblies being located in a same horizontal plane, the telescopic crossbar comprising a first crossbar and a second crossbar which are fitted one inside the other and are extendable / retractable relative to each other so that the telescopic crossbar is switchable between a retracted state and an extended state with a length greater than the retracted state, wherein a partition groove is provided on the first crossbar along an extension / retraction direction of the first crossbar, the partition groove being configured to divide the first crossbar into an upper crossbar and a lower crossbar; when the telescopic crossbar is in the retracted state, an upper end surface of the upper crossbar and an upper end surface of the second crossbar are lower than or flush with the support portions; when the telescopic crossbar is in the extended state, a fitted section of the second crossbar is lifted by the lower crossbar so that the upper end surface of the second crossbar is higher than the support portions, and a fitted section of the upper crossbar is lifted by the second crossbar so that the upper end surface of the upper crossbar is higher than the support portions, whereby the desk frame, when being connected to the desktop, presses against the desktop to provide a support.
2. The desk frame for a desk according to claim 1, wherein one end of the partition groove proximal to a free end of the first crossbar is open, and one end of the partition groove distal from the free end of the first crossbar is closed; a sliding shaft slidable along the partition groove is fixedly provided on the second crossbar, an upper side surface of the partition groove engages the sliding shaft; and while the fitted section of the second crossbar is lifted by the lower crossbar, the sliding shaft lifts the upper crossbar.
3. The desk frame for a desk according to claim 2, wherein a width of the partition groove is progressively diminished from a closed end towards an open end thereof, and an upper end surface of the lower crossbar is inclined; a height of the upper end surface of the lower crossbar is progressively increased from one side proximal to a fixed end of the first crossbar towards opposite side thereof; the sliding shaft engaging the upper end surface of the lower crossbar; and when the telescopic crossbar switches from the retracted state to the extended state, the sliding shaft slides along the partition groove and is lifted by the upper end surface of the lower crossbar, so that the second crossbar is lifted, and the upper crossbar is lifted while the sliding shaft is lifted.
4. The desk frame for a desk according to claim 2, wherein the upper end surface of the upper crossbar is a first arcuate surface, a height of the first arcuate surface proximal to a side of the free end of the first crossbar being lower than a height of the first arcuate surface proximal to a side of the fixed end of the first crossbar; the upper side surface of the partition groove is a second arcuate surface adapted to the first arcuate surface, so that the upper crossbar has a consistent thickness at respective positions along its length direction.
5. The desk frame for a desk according to claim 1, wherein the first crossbar is provided thereon with a lifting bevel inclined along a length direction of the first crossbar, and the second crossbar is provided thereon with an engaging bevel inclined along a length direction of the second crossbar, the engaging bevel being adapted to and engaging the lifting bevel; when the telescopic crossbar is in the retracted state, a higher end of the lifting bevel engages a higher end of the engaging bevel, and a lower end of the lifting bevel engages a lower end of the engaging bevel; and when the telescopic crossbar switches from the retracted state to the extended state, the engaging bevel slides along the lifting bevel, driving the lower end of the second crossbar to move towards the higher end of the first crossbar, whereby the second crossbar is lifted.
6. The desk frame for a desk according to claim 1, wherein the first crossbar is provided thereon with a lifting bevel inclined along a length direction of the first crossbar, and an engaging block is provided at a free end of the second crossbar, the engaging block engaging the lifting bevel so that when the telescopic crossbar switches from the retracted state to the extended state, the engaging block slides along the lifting bevel, whereby the second crossbar is lifted.
7. The desk frame for a desk according to claim 1, wherein the second crossbar is provided thereon with a lifting bevel inclined along a length direction of the second crossbar, and an engaging block is provided at the free end of the first crossbar, the engaging block engaging the lifting bevel, so that when the telescopic crossbar switches from the retracted state to the extended state, the engaging block slides along the lifting bevel, whereby the second crossbar is lifted.
8. The desk frame for a desk according to claim 1, wherein the first crossbar is provided thereon with a plurality of bosses distributed in a stepwise profile along a length direction of the first crossbar, and the second crossbar is provided thereon with an engaging surface engaging upper end surfaces of the bosses and a plurality of avoidance slots configured to avoid the bosses, so that when the telescopic crossbar switches from the retracted state to the extended state, the engaging surface switches from engaging a lower boss to engaging a higher boss to thereby lift the second crossbar; when the telescopic crossbar is in the retracted state, the plurality of bosses are inserted into the plurality of avoidance slots, respectively; and when the telescopic crossbar is in the extended state, the engaging surface is supported on one of the bosses to thereby lift the second crossbar.
9. The desk frame for a desk according to claim 1, wherein the second crossbar is provided thereon with a plurality of bosses distributed in a stepwise profile along a length direction of the second crossbar, and the first crossbar is provided thereon with an engaging surface engaging upper end surfaces of the bosses and a plurality of avoidance slots configured to avoid the bosses, so that when the telescopic crossbar switches from the retracted state to the extended state, the engaging surface switches from engaging a lower boss to engaging a higher boss to thereby lift the second crossbar; when the telescopic crossbar is in the retracted state, the plurality of bosses are inserted in the plurality of avoidance slots, respectively; and when the telescopic crossbar is in the extended state, one of the bosses is supported on the engaging surface to thereby lift the second crossbar.
10. A desk, comprising a desktop, wherein the desk further comprises a desk frame for a desk according to claim 1, leg assemblies are disposed under the desktop, each of the leg assemblies comprising a leg and a support frame fixed to an upper end of the leg, the support portion being disposed at the support frame, the support frame supporting the desktop via the support portion.