Belt tensioning device and 3D printer

Abstract

The utility model relates to the field of 3D printer equipment, and provides a belt tensioning device and a 3D printer, the belt tensioning device comprises a mounting base, the mounting base is provided with a containing position, a receding opening and a first threaded hole, the receding opening and the first threaded hole are oppositely formed in the two sides of the containing position, and the receding opening communicates with the containing position; the first bearing and the second bearing are coaxially mounted on the mounting base and oppositely arranged on the two sides of the containing position; the connecting shaft is installed in the first bearing and the second bearing, and one end of the connecting shaft is suitable for being connected with an output shaft of a motor; the belt wheel is located in the containing position and installed on the connecting shaft, and the belt wheel and the connecting shaft rotate synchronously. The 3D printer comprises the belt tensioning device. The motor output shaft can be prevented from bearing radial force, the load of the motor is reduced, the occurrence risk of an out-of-step phenomenon is reduced, and the movement precision of the nozzle is ensured, so that the printing quality is ensured.

Description

Technical Field

[0001] This application relates to the field of 3D printer devices, and particularly to a belt tensioning device and a 3D printer. Background Art

[0002] Currently, in order to improve the movement accuracy and stability of the 3D printer nozzle to ensure printing quality, 3D printers generally have a belt tensioning function. The nozzle is connected to the belt, and the belt is driven to rotate by a pulley directly installed on the output shaft of the motor. The pulley has no other support points. As the belt rotates, the nozzle is thus moved along a preset direction. When the belt needs to be tensioned, the distance between the pulley and the driven pulley (idler pulley) is adjusted to make the belt tighter or looser. In the above belt tensioning adjustment scheme, since the pulley is directly installed on the output shaft of the motor and the pulley has no other support points, when the belt is tensioned, the output shaft of the motor will be subjected to a large radial force, increasing the load on the motor and easily causing a stepping-out phenomenon, affecting the movement accuracy of the nozzle and thus the printing quality.

[0003] Therefore, there is an urgent need in the market for a solution that can reduce or avoid the radial force borne by the output shaft of the motor. Utility Model Content

[0004] To solve the above problems, this application provides a belt tensioning device and a 3D printer, which are ingeniously designed and simple in structure. This application can avoid the output shaft of the motor from bearing radial force, reduce the load on the motor, reduce the risk of stepping-out phenomenon, ensure the movement accuracy of the nozzle, and thus ensure the printing quality. The technical solutions adopted in this application are as follows:

[0005] A belt tensioning device, comprising:

[0006] A mounting seat, which is provided with a receiving position, a relief opening and a first threaded hole. The relief opening and the first threaded hole are oppositely arranged on both sides of the receiving position. The relief opening communicates with the receiving position. The receiving position is used for placing the pulley. The relief opening is used for passing through the belt. The first threaded hole is used for screwing with an adjusting screw; a first bearing and a second bearing, the first bearing and the second bearing are coaxially installed on the mounting seat and are oppositely arranged on both sides of the receiving position; a connecting shaft, the connecting shaft is installed in the first bearing and the second bearing, and one end of the connecting shaft is adapted to connect to the output shaft of the motor; a pulley, the pulley is located in the receiving position and is installed on the connecting shaft, and the pulley rotates synchronously with the connecting shaft.

[0007] This belt tensioning device can be manufactured and produced as an independent product. It can be used to retrofit and upgrade 3D printers without belt tensioning function to make them have belt tensioning function, and can also be used to retrofit and upgrade 3D printers with traditional belt tensioning function (the motor output shaft is subject to radial force), so that the motor driving the belt rotation in the 3D printer no longer bears the radial force. In this application, the output shaft of the motor is connected to the connecting shaft, and the rotation of the motor is transmitted to the pulley through the connecting shaft, so as to realize the driving of the belt. The belt tension is transmitted to the connecting shaft through the pulley, and the connecting shaft transmits the radial force to the first bearing and the second bearing. Finally, the first bearing and the second bearing bear the belt tension, which protects the motor. Using this belt tensioning device can avoid the motor output shaft from bearing the radial force, reduce the load of the motor, reduce the risk of the occurrence of out-of-step phenomenon, ensure the movement accuracy of the nozzle, and thus ensure the printing quality.

[0008] In some embodiments, the mounting seat is provided with a first mounting hole and a second mounting hole. The first mounting hole and the second mounting hole are oppositely arranged on both sides of the accommodating position. The first bearing is installed in the first mounting hole, and the second bearing is installed in the second mounting hole.

[0009] By installing the first bearing and the second bearing in the first mounting hole and the second mounting hole respectively, the distance between the first bearing and the second bearing can be made as small as possible, so that the thickness of the whole belt tensioning device (the same as the axial direction of the connecting shaft) can be made as small as possible, reducing the space occupied by the belt tensioning device.

[0010] In some embodiments, the connecting shaft includes a large-diameter section and a small-diameter section. The large-diameter section is located at one end of the small-diameter section. The small-diameter section is installed in the first bearing and the second bearing. The large-diameter section is provided with a blind hole and a plurality of setscrew mounting holes. The blind hole is coaxial with the connecting shaft, and the plurality of setscrew mounting holes are circumferentially spaced around the blind hole. The setscrew mounting holes are used to install setscrews, and the blind hole is used to insert the output shaft of the motor.

[0011] By providing a blind hole and setscrew mounting holes, the output shaft of the motor is inserted into the blind hole and fixed with setscrews. Compared with using a coupling to connect the motor output shaft and the connecting shaft, using a coupling increases the cost on the one hand, and on the other hand, using a coupling will increase the overall height after the motor and the belt tensioning device are assembled. However, this design can effectively control the overall height after the motor and the belt tensioning device are assembled, saving space.

[0012] In some embodiments, the connecting shaft further includes a middle-diameter section, and the middle-diameter section is located between the large-diameter section and the small-diameter section.

[0013] By providing the middle diameter section, a good transition can be achieved between the large diameter section and the small diameter section, thereby reducing the risk of stress concentration on the connecting shaft and thus reducing the probability of the connecting shaft breaking.

[0014] In some embodiments, a side of the middle diameter section close to the small diameter section abuts against the first bearing or the second bearing.

[0015] By making one side of the middle diameter section abut against the bearing (the first bearing or the second bearing), the gravity of the connecting shaft is borne by the bearing, reducing the axial force on the motor output shaft and ensuring smooth operation of the motor.

[0016] In some embodiments, the outer rings of the first bearing and the second bearing are both provided with flanges, the flange of the first bearing abuts against the mounting seat on a side close to the second bearing, and the flange of the second bearing abuts against the mounting seat on a side close to the first bearing.

[0017] By adopting a bearing (first bearing or second bearing) with a flange portion and making the flange portion abut against the mounting seat, relative displacement between the bearing and the mounting seat over time can be avoided, thereby ensuring the stability of the bearing position.

[0018] In some embodiments, the bearing close to the motor is defined as the first bearing, and the bearing away from the motor is defined as the second bearing; a limit member is provided at one end of the connecting shaft away from the motor, and the limit member abuts against the side of the second bearing away from the first bearing.

[0019] By providing a limiting member, the limiting member abuts against the second bearing to limit the displacement of the second bearing, thereby preventing the second bearing from being disengaged from the installation position or even falling off the connecting shaft.

[0020] In some embodiments, a slot is provided at one end of the connecting shaft away from the motor, and the limiting member is a retaining spring that is retained in the slot.

[0021] In some embodiments, the belt tensioning device further includes a raised seat, which is fixed to the mounting seat and located on a side of the mounting seat close to the motor. The raised seat is used to support the motor and provide space for the connection between the connecting shaft and the motor.

[0022] On the other hand, the present application provides a 3D printer comprising the aforementioned belt tensioning device.

[0023] The belt tensioning device and 3D printer provided in this application have at least one of the following beneficial effects:

[0024] 1. A belt tensioning device provided by the present application can be manufactured and produced as an independent product. It can be used to transform and upgrade 3D printers without belt tensioning function to make them have belt tensioning function, and can also be used to transform and upgrade 3D printers with traditional belt tensioning function (the motor output shaft is subject to radial force), so that the motor driving the belt rotation in the 3D printer no longer bears the radial force. In the present application, the output shaft of the motor is connected to the connecting shaft, and the rotation of the motor is transmitted to the pulley through the connecting shaft, so as to drive the belt. The belt tension is transmitted to the connecting shaft through the pulley, and the connecting shaft transmits the radial force to the first bearing and the second bearing. Finally, the first bearing and the second bearing bear the belt tension, which protects the motor. Using this belt tensioning device can avoid the motor output shaft from bearing the radial force, reduce the load of the motor, reduce the risk of out-of-step phenomenon, ensure the movement accuracy of the nozzle, and thus ensure the printing quality.

[0025] 2. A belt tensioning device provided by the present application can make the distance between the first bearing and the second bearing as small as possible by respectively installing the first bearing and the second bearing in the first mounting hole and the second mounting hole, so that the thickness of the whole belt tensioning device (in the axial direction of the connecting shaft) is as small as possible, reducing the space occupied by the belt tensioning device.

[0026] 3. A belt tensioning device provided by the present application, by setting the blind hole and the setscrew mounting hole, the output shaft of the motor is inserted into the blind hole and fixed with a setscrew. Compared with connecting the motor output shaft and the connecting shaft by using a coupling, using a coupling increases the cost on the one hand, and on the other hand, using a coupling will increase the overall height after assembling the motor and the belt tensioning device. However, this design can effectively control the overall height after assembling the motor and the belt tensioning device and save space.

[0027] 4. A belt tensioning device provided by the present application, by setting the middle diameter section, enables a good transition between the large diameter section and the small diameter section, reduces the risk of stress concentration on the connecting shaft, and thus reduces the probability of the connecting shaft breaking.

[0028] 5. A belt tensioning device provided by the present application, by making one side of the middle diameter section abut against the bearing (the first bearing or the second bearing), enables the gravity of the connecting shaft to be borne by the bearing, reduces the axial force on the motor output shaft, and ensures the stable operation of the motor.

[0029] 6. A belt tensioning device provided by the present application, by using a bearing (the first bearing or the second bearing) provided with a flange portion and making the flange portion abut against the mounting seat, can avoid the relative displacement between the bearing and the mounting seat as the use time increases, and ensure the stability of the bearing position.

[0030] 7. A belt tensioning device provided by the present application limits the displacement of the second bearing by providing a limiting member and using the abutment between the limiting member and the second bearing, preventing the second bearing from disengaging from its installation position or even falling off the connecting shaft. Description of the Drawings

[0031] The following will further illustrate the above characteristics, technical features, advantages and their implementation manners of a belt tensioning device and a 3D printer in a clear and understandable manner in combination with the drawings:

[0032] Figure 1 is the overall structural schematic diagram of an embodiment of the belt tensioning device of the present application;

[0033] Figure 2 is Figure 1 the sectional view of the embodiment;

[0034] Figure 3 is Figure 1 the exploded view of the embodiment;

[0035] Figure 4 is the overall structural schematic diagram of an embodiment of the connecting shaft of the present application;

[0036] Figure 5 is Figure 1 the overall structural schematic diagram of the embodiment after hiding the mounting seat;

[0037] Figure 6 is the overall structural schematic diagram of an embodiment of the first bearing / second bearing of the present application;

[0038] Figure 7 is the overall structural schematic diagram of an embodiment of the mounting seat of the present application;

[0039] Figure 8 is the state of the belt tensioning device of the present application after being installed on a 3D printer;

[0040] Figure 9 is Figure 8 another perspective of the embodiment;

[0041] Figure 10 is Figure 8 yet another perspective of the embodiment;

[0042] Figure 11 is Figure 8 the sectional view of the embodiment.

[0043] Explanation of the Reference Numerals in the Drawings:

[0044] Mounting base 1, receiving position 2, relief opening 3, first threaded hole 4, belt 5, pulley 6, first bearing 7, second bearing 8, connecting shaft 9, motor 10, adjusting screw 11, first mounting hole 12, second mounting hole 13, large diameter section 14, small diameter section 15, blind hole 16, setscrew mounting hole 17, setscrew 18, middle diameter section 19, flange portion 20, card slot 21, snap ring 22, heightening seat 23, mounting frame body 24, fixing plate 25, waist-shaped hole 26. Detailed implementation manners

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will describe the specific implementation manners of the present application with reference to the accompanying drawings. Obviously, the accompanying drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained according to these drawings, and other implementation manners can be obtained.

[0046] To make the drawings concise, only the parts related to the present application are schematically shown in each drawing, and they do not represent the actual structure of the product. Additionally, to make the drawings concise and easy to understand, in some drawings, components with the same structure or function are only schematically shown for one of them, or only one of them is marked. In this document, "one" not only means "only this one", but also means "more than one" situation.

[0047] It should also be further understood that the term "and / or" used in the specification and appended claims of the present application refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0048] In this document, it should be noted that unless otherwise clearly specified and limited, the terms "mount", "connect", and "couple" 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 or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0049] In addition, in the description of the present application, the terms "first", "second", etc. are only used for distinguishing descriptions, and cannot be understood as indicating or implying relative importance.

[0050] Refer to Figures 1-3 、 Figures 7-11, this application provides a belt tensioning device, including: a mounting base 1, the mounting base 1 is provided with a receiving position 2, a relief opening 3 and a first threaded hole 4. The relief opening 3 and the first threaded hole 4 are oppositely arranged on both sides of the receiving position 2. The relief opening 3 communicates with the receiving position 2. The receiving position 2 is used for placing a pulley 6. The relief opening 3 is used for threading a belt 5. The first threaded hole 4 is used for screwing with an adjusting screw 11; a first bearing 7 and a second bearing 8, the first bearing 7 and the second bearing 8 are coaxially installed on the mounting base 1 and are oppositely arranged on both sides of the receiving position 2; a connecting shaft 9, the connecting shaft 9 is installed in the first bearing 7 and the second bearing 8, and one end of the connecting shaft 9 is adapted to connect to the output shaft of a motor 10; a pulley 6, the pulley 6 is located in the receiving position 2 and is installed on the connecting shaft 9, and the pulley 6 rotates synchronously with the connecting shaft 9.

[0051] Specifically, this belt tensioning device can be manufactured and produced as an independent product. It can be used to transform and upgrade a 3D printer without a belt tensioning function to make it have a belt tensioning function, and can also be used to transform and upgrade a 3D printer with a traditional belt tensioning function (the output shaft of the motor 10 is subject to radial force), so that the motor 10 that drives the belt 5 to rotate in the 3D printer no longer bears the radial force.

[0052] Specifically, after this belt tensioning device is installed on the 3D printer, the output shaft of the motor 10 is connected to the connecting shaft 9. The rotation of the motor 10 is transmitted to the pulley 6 through the connecting shaft 9, thereby realizing the drive of the belt 5. And the tension of the belt 5 is transmitted to the connecting shaft 9 through the pulley 6. The connecting shaft 9 transmits the radial force to the first bearing 7 and the second bearing 8. Finally, the first bearing 7 and the second bearing 8 bear the tension of the belt 5, which protects the motor 10. Using this belt tensioning device can avoid the output shaft of the motor 10 from bearing the radial force, reduce the load of the motor 10, reduce the risk of the occurrence of out-of-step phenomenon, ensure the movement accuracy of the nozzle, and thus ensure the printing quality.

[0053] It should be noted that referring to Figures 1-3 , Figure 7 , Figure 11 , in one embodiment, the mounting base 1 is provided with a first mounting hole 12 and a second mounting hole 13. The first mounting hole 12 and the second mounting hole 13 are oppositely arranged on both sides of the receiving position 2. The first bearing 7 is installed in the first mounting hole 12, and the second bearing 8 is installed in the second mounting hole 13.

[0054] It can be understood that by installing the first bearing 7 and the second bearing 8 in the first mounting hole 12 and the second mounting hole 13 respectively, the distance between the first bearing 7 and the second bearing 8 can be made as small as possible, so that the thickness of the entire belt tensioning device (in the axial direction of the connecting shaft 9) can be made as small as possible, reducing the space occupied by the belt tensioning device. In other embodiments, a bearing fixing seat can be provided on the mounting seat 1, and the first bearing 7 and the second bearing 8 can be fixed in the bearing fixing seat. Specifically, the bearing fixing seat can be integrally formed with the mounting seat 1 or detachably connected to the mounting seat 1.

[0055] Reference Figures 1-5 、 Figure 11 , in one embodiment, the connecting shaft 9 includes a large-diameter section 14 and a small-diameter section 15. The large-diameter section 14 is located at one end of the small-diameter section 15. The small-diameter section 15 is installed in the first bearing 7 and the second bearing 8. The large-diameter section 14 is provided with a blind hole 16 and a plurality of setscrew mounting holes 17. The blind hole 16 is coaxial with the connecting shaft 9. The plurality of setscrew mounting holes 17 are circumferentially spaced around the blind hole 16. The setscrew mounting holes 17 are used to install setscrews 18, and the blind hole 16 is used to insert the output shaft of the motor 10.

[0056] It is easy to understand that by providing the blind hole 16 and the setscrew mounting holes 17, the output shaft of the motor 10 is inserted into the blind hole 16 and fixed with the setscrew 18. Compared with connecting the output shaft of the motor 10 and the connecting shaft 9 by using a coupling, using a coupling increases the cost on the one hand, and on the other hand, using a coupling will increase the overall height after assembling the motor 10 and the belt tensioning device. However, this design can effectively control the overall height after assembling the motor 10 and the belt tensioning device, saving space. In other embodiments, the connection between the output shaft of the motor 10 and the connecting shaft 9 can be realized by using a coupling or by using the cooperation of a keyway and a key.

[0057] It should be noted that, reference Figures 1-5 、 Figure 11 , in one embodiment, the connecting shaft 9 further includes a middle-diameter section 19. The middle-diameter section 19 is located between the large-diameter section 14 and the small-diameter section 15. By providing the middle-diameter section 19, a good transition can be achieved between the large-diameter section 14 and the small-diameter section 15, reducing the risk of stress concentration on the connecting shaft 9, thereby reducing the probability of the connecting shaft 9 breaking. In other embodiments, the middle-diameter section 19 may not be provided, and a tapered section may be provided instead of the middle-diameter section 19.

[0058] It should be noted that, reference Figures 1-5 、 Figure 11, in one embodiment, one side of the middle diameter section 19 close to the small diameter section 15 abuts against the first bearing 7 or the second bearing 8. By making one side of the middle diameter section 19 abut against the bearing (the first bearing 7 or the second bearing 8), the gravity of the connecting shaft 9 is borne by the bearing, reducing the axial force on the output shaft of the motor 10 and ensuring the stable operation of the motor 10.

[0059] Reference Figure 2 , Figure 3 , Figure 5 , Figure 6 , Figure 11 , in one embodiment, flange portions 20 are provided on the outer rings of both the first bearing 7 and the second bearing 8. The flange portion 20 of the first bearing 7 abuts against the mounting seat 1 on the side close to the second bearing 8, and the flange portion 20 of the second bearing 8 abuts against the mounting seat 1 on the side close to the first bearing 7. By using the bearing (the first bearing 7 or the second bearing 8) provided with the flange portion 20 and making the flange portion 20 abut against the mounting seat 1, it is equivalent to the mounting seat 1 being clamped between the flange portion 20 of the first bearing 7 and the flange portion 20 of the second bearing 8, which can avoid the relative displacement between the bearing and the mounting seat 1 with the increase of the use time and ensure the stability of the bearing position.

[0060] In one embodiment, the bearing close to the motor 10 is defined as the first bearing 7, and the bearing far from the motor 10 is defined as the second bearing 8; a limiting member is provided at one end of the connecting shaft 9 far from the motor 10, and the limiting member abuts against the side of the second bearing 8 far from the first bearing 7. By providing the limiting member, the displacement of the second bearing 8 is restricted by the abutment of the limiting member against the second bearing 8, preventing the second bearing 8 from disengaging from the mounting position or even falling off the connecting shaft 9.

[0061] Specifically, referring to Figure 2 , Figure 4 , Figure 5 , the limiting member can be a snap ring 22. A clamping groove 21 is provided at one end of the connecting shaft 9 far from the motor 10, and the snap ring 22 is clamped in the clamping groove 21, and the snap ring 22 abuts against the side of the second bearing 8 far from the first bearing 7. The limiting member can also be a rod-shaped member. A perforation is provided at one end of the connecting shaft 9 far from the motor 10, and the perforation is arranged along the radial direction of the connecting shaft 9, and the rod-shaped member is inserted into the perforation.

[0062] Reference Figures 8-11 , in one embodiment, the belt tensioning device further includes a heightening seat 23. The heightening seat 23 is fixed to the mounting seat 1 and is located on the side of the mounting seat 1 close to the motor 10. The heightening seat 23 is used to support the motor 10 and provide space for the connection between the connecting shaft 9 and the motor 10.

[0063] Reference Figures 8-11, this application also provides a 3D printer, including the aforementioned belt tensioning device. For the specific structure of this belt tensioning device, refer to the foregoing embodiments. Since this 3D printer adopts the technical solutions of the foregoing embodiments, it at least has the beneficial effects brought by the technical solutions of the foregoing embodiments, which will not be elaborated here one by one.

[0064] Specifically, referring to Figures 8-11 , the 3D printer includes a mounting frame 24. The mounting seat 1 of the belt tensioning device is provided with a waist-shaped hole 26. The belt tensioning device is detachably mounted on the mounting frame 24 through the cooperation of the waist-shaped hole 26 and the bolt assembly. One end of the mounting frame 24 is connected with a fixing plate 25, and the fixing plate 25 is also located on one side of the belt tensioning device. The fixing plate 25 is provided with a through hole for passing through the adjusting screw 11, and the position of the through hole corresponds to the first threaded hole 4 on the mounting seat 1. The threaded rod of the adjusting screw 11 passes through the through hole and is screwed into the first threaded hole 4, and the head of the adjusting screw 11 is exposed outside the through hole.

[0065] The process of tensioning the belt 5 by using the belt tensioning device is as follows: Loosen the threaded assembly passing through the waist-shaped hole 26 so that the mounting seat 1 can move relative to the mounting frame 24, and then turn the adjusting screw 11. The head of the adjusting screw 11 abuts against the fixing plate 25. By turning the adjusting screw 11, the screwing depth of the adjusting screw 11 and the first threaded hole 4 gradually becomes deeper, so that the mounting seat 1 gradually approaches the fixing plate 25, thereby increasing the distance between the pulley 6 and the driven pulley (idler pulley), and further tensioning the belt 5. When the tension degree of the belt 5 meets the requirements, the rotation of the adjusting screw 11 can be stopped, and the threaded assembly passing through the waist-shaped hole 26 can be tightened to fix the mounting seat 1.

[0066] It should be noted that the above embodiments can be freely combined according to needs. The above is only the preferred embodiment of this application. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of this application, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of this application.

Claims

1. A belt tensioning device, characterized in that, Comprising: A mounting base, which is provided with a receiving position, a relief opening and a first threaded hole. The relief opening and the first threaded hole are oppositely arranged on both sides of the receiving position. The relief opening communicates with the receiving position. The receiving position is used for placing a pulley, the relief opening is used for passing a belt through, and the first threaded hole is used for screwing with an adjusting screw. A first bearing and a second bearing, which are coaxially installed on the mounting base and are oppositely arranged on both sides of the receiving position. A connecting shaft, which is installed in the first bearing and the second bearing. One end of the connecting shaft is adapted to connect to the output shaft of a motor. A pulley, which is located in the receiving position and is installed on the connecting shaft. The pulley rotates synchronously with the connecting shaft.

2. The belt tensioning device according to claim 1, wherein The mounting base is provided with a first mounting hole and a second mounting hole. The first mounting hole and the second mounting hole are oppositely arranged on both sides of the receiving position. The first bearing is installed in the first mounting hole, and the second bearing is installed in the second mounting hole.

3. A belt tensioning device according to claim 1, characterized in that, The connecting shaft includes a large-diameter section and a small-diameter section. The large-diameter section is located at one end of the small-diameter section. The small-diameter section is installed in the first bearing and the second bearing. The large-diameter section is provided with a blind hole and a plurality of setscrew mounting holes. The blind hole is coaxial with the connecting shaft. The plurality of setscrew mounting holes are circumferentially spaced around the blind hole. The setscrew mounting holes are used for installing setscrews, and the blind hole is used for plugging the output shaft of the motor.

4. A belt tensioning device according to claim 3, characterized in that, The connecting shaft further includes a middle-diameter section, which is located between the large-diameter section and the small-diameter section.

5. A belt tensioning device according to claim 4, characterized in that, One side of the middle-diameter section close to the small-diameter section abuts against the first bearing or the second bearing.

6. A belt tensioning device according to any one of claims 1-5, characterized in that Flange portions are provided on the outer rings of the first bearing and the second bearing. The flange portion of the first bearing abuts against the mounting base on the side close to the second bearing, and the flange portion of the second bearing abuts against the mounting base on the side close to the first bearing.

7. A belt tensioning device according to claim 6, characterized in that, Define the bearing close to the motor as the first bearing, and the bearing far from the motor as the second bearing; a limiting member is provided at the end of the connecting shaft far from the motor, and the limiting member abuts against the side of the second bearing far from the first bearing.

8. A belt tensioning device according to claim 7, characterized in that, A clamping groove is provided at the end of the connecting shaft far from the motor, and the limiting member is a circlip, which is clamped in the clamping groove.

9. A belt tensioning device according to any one of claims 1-5, 7, and 8, characterized in that, It further includes a heightening base, which is fixed to the mounting base and is located on the side of the mounting base close to the motor. The heightening base is used for supporting the motor and providing space for the connection between the connecting shaft and the motor.

10. A 3D printer, characterized in that, Comprising the belt tensioning device according to any one of claims 1-9.

Images