Belt tensioning mechanism for 3D printer and 3D printer

Abstract

A belt tensioning mechanism for a 3D printer and a 3D printer, the belt tensioning mechanism comprising a base, a driving wheel, at least one synchronous pulley, a slider, a tensioning wheel, a spring, a tensioning wheel cover and a locking screw. The base is provided with a first slide groove. The driving wheel and at least one synchronous pulley are mounted on the base and connected in series with each other through a belt. The slider is mounted on the base and can slide along the first slide groove. The tensioning wheel is mounted on the slider and connected in series with the driving wheel and at least one synchronous pulley through a belt for tensioning the belt. The spring is used to apply elastic force to the slider. The tensioning wheel cover is fixedly mounted on the base and is provided with a second slide groove corresponding to the first slide groove. The locking screw passes through the second slide groove and is threadedly connected to a threaded hole in the slider, so that the slider is locked and fixed relative to the tensioning wheel cover.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This disclosure claims priority to Chinese Patent Application No. 2021225122569 filed on October 19, 2021, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0003] The present disclosure relates to 3D printing technology, and in particular to a belt tensioning mechanism for a 3D printer and a 3D printer. Background Art

[0004] A 3D printer, also known as a three-dimensional printer, is a machine that uses rapid prototyping technology. It can construct three-dimensional objects by printing layer by layer using adhesive materials such as powdered metal or plastic. In related technologies, when a 3D printer is printing, the printing platform that receives the printing material moves vertically through a screw and a synchronous pulley under the action of a belt.

[0005] In the related art, the user needs to manually tighten the bolts to tighten the synchronous belt. Different users set different tensioning positions, resulting in inconsistent belt tensioning forces for different machines, which can easily cause problems such as low lifting accuracy of the printing platform or high machine wear. Summary of the invention

[0006] It would be advantageous to provide a mechanism that alleviates, mitigates, or even eliminates one or more of the above-mentioned problems.

[0007] According to one aspect of the present disclosure, a belt tensioning mechanism for a 3D printer is provided, comprising: the 3D printer comprises at least one lead screw arranged in a vertical direction and a printing platform sleeved on the at least one lead screw. The belt tensioning mechanism comprises: a base, provided with a first slide groove; a driving wheel and at least one synchronous pulley mounted on the base and connected to each other through a belt, the at least one synchronous pulley being used to drive the at least one lead screw to rotate respectively under the drive of the driving wheel, so that the printing platform can be lifted and lowered relative to the base along the at least one lead screw; a slider mounted on the base and capable of sliding along the first slide groove; a tensioning wheel, the tensioning wheel being mounted on the slider and connected to the driving wheel and at least one synchronous pulley through a belt for tensioning the belt; a spring, used to apply elastic force to the slider so that the slider is in a working position in the first slide groove, in which the tensioning wheel tensions the belt; a tensioning wheel cover, the tensioning wheel cover being fixedly mounted on the base and provided with a second slide groove corresponding to the first slide groove; and a locking screw, the locking screw passing through the second slide groove and being screwed to the threaded hole in the slider, so that the slider is locked and fixed relative to the tensioning wheel cover.

[0008] According to another aspect of the present disclosure, a 3D printer is provided, comprising: at least one lead screw arranged in a vertical direction; a printing platform sleeved on the at least one lead screw; and the belt tensioning mechanism as described above.

[0009] These and other aspects of the disclosure will be apparent from and elucidated with reference to the embodiments described hereinafter. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Further details, features and advantages of the present disclosure are disclosed in the following description of example embodiments in conjunction with the accompanying drawings, in which:

[0011] Figure 1 A structural diagram of a belt tensioning mechanism for a 3D printer according to one embodiment of the present disclosure is shown;

[0012] Figure 2 for Figure 1 A zoomed-in view of a view near the middle slider; and

[0013] Figure 3 for Figure 1 A partial enlargement of another perspective near the middle slider. DETAILED DESCRIPTION

[0014] In the present disclosure, unless otherwise specified, the use of the terms "first", "second", etc. to describe various elements is not intended to limit the positional relationship, timing relationship, or importance relationship of these elements, and such terms are only used to distinguish one element from another element. In some examples, the first element and the second element may refer to the same instance of the element, and in some cases, based on the description of the context, they may also refer to different instances.

[0015] The terms used in the description of various examples in this disclosure are for the purpose of describing specific examples only and are not intended to be limiting. Unless the context clearly indicates otherwise, if the number of elements is not specifically limited, the element can be one or more. As used herein, the term "plurality" means two or more, and the term "based on" should be interpreted as "based at least in part on". In addition, the terms "and / or" and "at least one of" cover any one of the listed items and all possible combinations.

[0016] Exemplary embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

[0017] In the related art, the belt tensioning mechanism used in 3D printers usually includes a tensioning wheel, a sliding block, a belt and a bolt. The tensioning wheel is mounted on the sliding block, and the sliding block is provided with a screw thread, which is connected to the bolt. When the belt becomes loose after long-term use, the user is required to rotate the bolt by hand, and the bolt drives the idler slider to move along the axis of the bolt, thereby tensioning the synchronous belt. In such a scheme, the user needs to manually tighten the bolt to tension the synchronous belt, and the final tensioning force is completely controlled by the user's feel. Different users have different torques on the bolts, resulting in inconsistent belt tensioning forces for different machines. When the belt is too loose, it may cause the hidden danger of inconsistent lifting height of the hot bed platform when the machine is running. When the belt is too tight, it may increase the transmission resistance of the entire machine and aggravate the wear of the machine.

[0018] In view of this, an embodiment of the present disclosure provides a belt tensioning mechanism for a 3D printer, which uses a spring to provide a relatively constant tensioning force. The user does not need to judge the tensioning force by feel, thereby avoiding problems caused by inconsistent tensioning force.

[0019] Figure 1 A structural diagram of a belt tensioning mechanism 10 for a 3D printer according to one embodiment of the present disclosure is shown. Figure 2 for Figure 1 A partial zoomed view of a view near the middle slider. Figure 3 for Figure 1 A partial enlarged view of another angle of view near the middle slider. The 3D printer may include at least one screw (not shown) arranged in a vertical direction and a printing platform (not shown) sleeved on the at least one screw.

[0020] Please refer to Figures 1 to 3 The belt tensioning mechanism 10 includes: a base 110, a driving wheel 130, at least one synchronous pulley ( Figure 1 In the example, a first synchronous pulley 140A, a second synchronous pulley 140B and a third synchronous pulley 140C), a slider 150, a tensioning wheel 160, a spring 170, a tensioning wheel cover 180 and a locking screw 190. The driving wheel 130 drives at least one synchronous pulley to rotate, and at least one synchronous pulley drives the corresponding lead screw to rotate, so that the printing platform mounted on the lead screw moves up and down in the vertical direction. At least one lead screw can be installed on the corresponding synchronous pulley in any appropriate manner (for example, threaded connection, fastening connection, etc.), as long as at least one lead screw can move up and down in the vertical direction as the synchronous pulley rotates. Figure 1 In the example, for example, three lead screws (not shown) may be provided, which are coaxially fixed to the first synchronous pulley 140A, the second synchronous belt 140B, and the third synchronous pulley 140C, respectively.

[0021] The base 110 may be a frame structure or a plate structure. The horizontal plane of the base 110 may be in a square, rectangular or circular shape, for example. The base 110 is provided with a first slide groove 111 .

[0022] The driving wheel 130 and at least one synchronous pulley are mounted on the base 110. The positional relationship between the driving wheel 130 and at least one synchronous pulley is not particularly limited. Figure 1 In the example of , the driving wheel 130 is arranged to be closest to the third synchronous pulley 140C among the first synchronous pulley 140A, the second synchronous pulley 140B and the third synchronous pulley 140C, but the present disclosure is not limited thereto. The driving wheel 130, the first synchronous pulley 140A, the second synchronous pulley 140B and the third synchronous pulley 140C are connected in series with each other through the belt 120. The first synchronous pulley 140A, the second synchronous pulley 140B and the third synchronous pulley 140C are driven by the driving wheel 130 to respectively drive the corresponding screws to rotate, so that the printing platform can be raised and lowered relative to the base 110 along the screws.

[0023] Please refer to Figure 1 and Figure 2 The belt tensioning mechanism 10 includes a slider 150, a tensioning wheel 160 and a spring 170. The spring 170 applies elastic force to the slider 150, and the slider 150 drives the tensioning wheel 160 to move, so that the tensioning wheel 160 applies tensioning force to the belt 120. It should be noted that since the spring 170 is used to apply the elastic force, the user does not need to rely on feeling to judge the magnitude of the elastic force, ensuring that even different users can apply the same elastic force to the slider 150 as long as the spring 170 of the same specification is used, thereby ensuring that the magnitude of the tensioning force applied to the belt 120 via the slider 150 and the tensioning wheel 160 is relatively constant.

[0024] The slider 150 is mounted on the base 110 and can slide along the first slide groove 111 of the base 110. The slider 150 is provided with a threaded hole. The shape of the slider 150 can be a rectangular parallelepiped, but is not limited thereto. The slider 150 can be made of iron, copper or plastic. In one example, the slider 150 is engaged with the first slide groove 111 so that the slider 150 only moves along the first slide groove 111. In one example, the slider 150 will not slide away from the first slide groove 111 along the length direction of the first slide groove 111. For this purpose, a stop portion for stopping the slider 150 can be provided at both ends of the length direction of the first slide groove 111.

[0025] The tensioning wheel 160 is mounted on the slider 150 and is connected in series with the driving wheel 130 and at least one synchronous pulley 140 through the belt 120 to tension the belt 120. The tensioning wheel 160 can move integrally with the slider 150.

[0026] Please refer to Figures 1 to 3As a possible implementation, the spring 170 may be a torsion spring having a torsion spring body 173 , a first cantilever 171 and a second cantilever 172 , and the base 110 further includes a torsion spring fixing column 200 and a torsion spring limiting column 210 .

[0027] In this implementation, the torsion spring body 173 is sleeved on the torsion spring fixing column 200, the first cantilever 171 of the torsion spring abuts on the torsion spring limiting column 210, and the second cantilever 172 of the torsion spring abuts on the slider 150. When a tensioning force is applied to the belt 120, the torsion spring applies an elastic force to the slider 150 through the second cantilever 172 by torque, pushing the slider 150 so that the slider 150 is in a working position in the first slide groove 111, and at this working position, the tensioning wheel 160 tensions the belt 120.

[0028] By reasonably setting the position of the torsion spring fixing column 200 and the length of the torsion spring cantilever, a constant thrust can be maintained when the torsion spring pushes the slider 150 to slide within a small range. For example, when the torsion spring pushes the slider 150, on the one hand, the working angle of the torsion spring becomes larger, and the angle change will cause the torque of the torsion spring to decrease. On the other hand, by reasonably setting the position of the torsion spring fixing column 200 and the length of the torsion spring cantilever, the cantilever length from the contact point between the torsion spring and the slider 150 to the torsion spring fixing column 200 can be shortened year-on-year, thereby keeping the thrust fixed.

[0029] In some embodiments, the base 110 may not be provided with a torsion spring fixing column 200 but only with a torsion spring limiting column 210. In such an embodiment, the first cantilever 171 of the torsion spring may be fixed on the torsion spring limiting column 210, and the second cantilever 172 of the torsion spring still abuts against the slider 150. At this time, the torsion spring may also apply elastic force to the slider 150 through the second cantilever 172 by torsion.

[0030] Since a torsion spring is used as the spring 170 to apply elastic force to the slider 150, the user does not need to rely on feeling to judge the size of the elastic force, ensuring that even different users can apply the same elastic force to the slider 150 as long as the torsion spring of the same specification is used, thereby ensuring the size of the tensioning force applied by the tensioning wheel 160 to the belt 120.

[0031] As another possible implementation, the spring 170 of the belt tensioning mechanism 10 may be a compression spring or a tension spring. In the embodiment where the spring 170 is a compression spring, one end of the compression spring may be fixed to a compression spring fixing column (not shown), and the other end of the compression spring may be fixed to the slider 150. When the compression spring applies elastic force to the slider 150, the compression spring is compressed to generate elastic force, achieving an automatic tensioning effect similar to that of a torsion spring.

[0032] As another possible implementation, the spring 170 of the belt tensioning mechanism 10 may also be a tension spring. In the embodiment where the spring 170 is a tension spring, one end of the tension spring may be fixed to a tension spring fixing column (not shown), and the other end of the tension spring may be fixed to the slider 150. When the tension spring applies elastic force to the slider 150, the tension spring is stretched to generate elastic force, achieving an automatic tensioning effect similar to that of a torsion spring.

[0033] It can be understood that compared with the case of using a torsion spring, when a compression spring or a tension spring is used, when the slider 150 slides a small distance, the elastic force of the compression spring or the tension spring varies in a small range. Although a constant tensioning force cannot be achieved, a small range of tensioning force changes can still be achieved.

[0034] The belt tensioning mechanism 10 also includes a tensioning wheel cover 180 and a locking screw 190. The locking screw 190 fixes the slider 150 relative to the tensioning wheel cover 180, ensuring that the slider 150 can be located in the working position for a long time, thereby ensuring that the slider 150 can apply tension to the belt 120 for a long time, thereby improving the stability of the tension. After the locking screw 190 is tightened, the slider 150 is locked in a fixed position. After a long period of use, if the user finds that the belt tension becomes smaller, he only needs to loosen the locking screw 190 and then tighten the locking screw 190, and the belt 120 will be automatically tensioned, and the tension is maintained near the design value.

[0035] The tension wheel cover 180 is fixedly mounted on the base 110 and is provided with a second slide groove 181 corresponding to the first slide groove 111. The tension wheel cover 180 can be fixedly connected to the base 110 by screws 220, but is not limited thereto. The locking screw 190 is used in conjunction with the tension wheel cover 180. In order to lock and fix the slider 150 relative to the tension wheel cover 180, the locking screw 190 passes through the second slide groove 181 of the tension wheel cover 180 and is screwed to the threaded hole in the slider 150, so that the slider 150 is locked and fixed relative to the tension wheel cover 180. When the user uses it normally, the locking screw 190 is in a locked state, and the locking screw 190 will have a large friction force with the surface of the second slide groove 181, thereby locking the slider 150 and the tension wheel 160 in a fixed position. When the user needs to adjust the belt tension, the user loosens the locking screw 190, and the spring can push the slider 150 to slide, so that the tension reaches the designed value. After the user has finished adjusting, he can just tighten the locking screw 190. Of course, the fixing connection method of the locking screw 190 and the tensioning wheel cover 180 is not limited to threading. The fixing mechanism such as the tensioning wheel cover 180 and the locking screw 190 can keep the slider 150 in a fixed state, thereby ensuring that the slider 150 can be located in the same working position for a long time, and improving the stability of the tensioning force.

[0036] The embodiment of the present disclosure also provides a 3D printer. The 3D printer includes: at least one screw, a printing platform and a belt tensioning mechanism 10 for the 3D printer. The at least one screw is arranged in a vertical direction, and the printing platform is sleeved on the at least one screw. The structure and function of the belt tensioning mechanism 10 for the 3D printer are the same as those in the above embodiment, and the above embodiment can be referred to for details, and no further description is given here.

[0037] The printing platform is sleeved on the lead screw, and the driving wheel 130 can drive the synchronous pulley and the lead screw to rotate, so that the printing platform can move up and down in the vertical direction as the lead screw rotates. In this embodiment, the printing platform is sleeved on three lead screws, but it is not limited to this. The number of sleeved lead screws can be increased according to the user's requirements for printing accuracy and printing platform movement stability. For example, the printing platform can be sleeved on one, two, four or more lead screws.

[0038] By using the belt tensioning mechanism 10 for a 3D printer according to the above embodiment, the problem of low precision in the height of the printing platform caused by a loose belt or aggravated wear of the machine caused by a tight belt is solved.

[0039] In the present disclosure, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present disclosure can be understood according to specific circumstances.

[0040] In the present disclosure, unless otherwise expressly specified and limited, a first feature being “above” or “below” a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being “above”, “above”, and “above” a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0041] This specification provides many different embodiments or examples that can be used to implement the present disclosure. It should be understood that these different embodiments or examples are entirely illustrative. The scope of protection of the present disclosure shall be subject to the scope of protection defined by the attached claims.

[0042] Description of reference numerals:

[0043] 10: Belt tensioning mechanism;

[0044] 110: base;

[0045] 111: first chute;

[0046] 120: belt;

[0047] 130: driving wheel;

[0048] 140A: first synchronous pulley;

[0049] 140B: second synchronous pulley;

[0050] 140C: the third synchronous pulley;

[0051] 150: Slider;

[0052] 160: tension wheel;

[0053] 170: Spring;

[0054] 171: first cantilever;

[0055] 172: Second cantilever;

[0056] 173: Torsion spring body;

[0057] 180: tension wheel cover;

[0058] 181: second chute;

[0059] 190: Locking screw;

[0060] 200: torsion spring fixing column;

[0061] 210: torsion spring limiting column;

[0062] 220: Screws.

Claims

1. A belt tensioning mechanism for a 3D printer, wherein: The 3D printer includes at least one screw rod, and the belt tensioning mechanism includes: A base is provided with a first slide groove; A tension wheel cover, the tension wheel cover is fixed on the base; A driving wheel and at least one synchronous pulley mounted on the base and connected to each other via a belt, wherein the at least one synchronous pulley is used to drive the at least one screw rod to rotate under the drive of the driving wheel; A slider, mounted on the base and capable of sliding along the first slide groove; A tensioning wheel, which is mounted on the slider and is connected in series with the driving wheel and the at least one synchronous pulley through the belt to tension the belt; a spring, used for applying elastic force to the slider to make the slider in a working position in the first slide slot, in which the tensioning wheel tensions the belt; A locking screw passes through the slider to lock and fix the slider relative to the tensioning wheel cover.

2. The belt tensioning mechanism according to claim 1, wherein: The tension wheel cover is provided with a second slide groove corresponding to the first slide groove, and the locking screw passes through the second slide groove and is screwed into the threaded hole in the slider, so that the slider is locked and fixed relative to the tension wheel cover.

3. The belt tensioning mechanism according to claim 1, wherein: The tension wheel cover is fixedly connected to the base via screws.

4. The belt tensioning mechanism according to any one of claims 1 to 3, wherein: The spring is a torsion spring.

5. The belt tensioning mechanism according to claim 4, wherein: The base is also provided with a torsion spring limiting column, and the torsion spring is connected between the torsion spring limiting column and the sliding block.

6. The belt tensioning mechanism according to claim 5, wherein: The base is also provided with a torsion spring fixing column, and the torsion spring body of the torsion spring is sleeved on the torsion spring fixing column.

7. The belt tensioning mechanism according to claim 6, wherein: The torsion spring limiting column and the torsion spring fixing column are arranged on the same side of the first sliding slot.

8. The belt tensioning mechanism according to claim 7, wherein: The first cantilever of the torsion spring is fixed on the torsion spring limiting column, and the second cantilever of the torsion spring abuts against the slider, so that when the torsion spring pushes the slider to slide within a small range, the cantilever length from the contact point between the torsion spring and the slider to the torsion spring fixing column becomes shorter year on year.

9. The belt tensioning mechanism according to any one of claims 1 to 3, wherein: The spring is a compression spring or a tension spring.

10. The belt tensioning mechanism according to any one of claims 1 to 8, wherein: Along the length direction of the first sliding groove, two opposite ends of the first sliding groove are respectively provided with stop parts to limit the displacement of the sliding block relative to the first sliding groove.

11. A 3D printer, wherein: The 3D printer comprises: At least one screw; And the belt tensioning mechanism according to any one of claims 1 to 10.

12. The 3D printer according to claim 11, wherein: The 3D printer includes at least one lead screw arranged in a vertical direction and a printing platform sleeved on the at least one lead screw, and the at least one synchronous pulley is used to drive the at least one lead screw to rotate under the drive of the driving wheel, so that the printing platform can be lifted and lowered along the at least one lead screw.

13. The 3D printer according to claim 12, wherein: There are three screw rods and three synchronous pulleys. Each screw rod is mounted on one synchronous pulley. The three synchronous pulleys are connected in series with each other through belts and drive the corresponding screw rod to rotate under the drive of one driving wheel.

14. The 3D printer according to claim 13, wherein: The three screw rods are distributed in a triangle shape, and the printing platform is sleeved on the three screw rods.

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