CN107091320B - Micro gearbox and its output shaft - Google Patents

Abstract

The invention relates to the technical field of gear boxes, and discloses a miniature gear box and an output shaft thereof. The micro gearbox includes a casing, a planet carrier arranged in the casing and close to the inner end surface of its output end, and an output shaft that penetrates the output end of the casing and is rotated and positioned with the planet carrier, wherein the output shaft includes a shaft body , and a positioning part coaxially arranged at the rear end of the shaft body, the positioning part and the planet carrier are limitedly matched along the central axis of the output shaft and toward the outer end of the shaft body, and the outer end of the shaft body and the outer end surface of the output end are spaced along the The central axis is positioned towards the rear end of the shaft body. The micro gearbox and its output shaft proposed by the present invention effectively prevent the axial movement of the output shaft, improve the overall operation stability of the micro gear box, and extend the service life. In addition, the micro gear box has a simple structure and is easy to process. It is easy to assemble, and its output shaft has good versatility and can be applied to both ordinary diameter gearboxes and micro-diameter gearboxes.

Description

Micro gearbox and its output shaft

Technical field

The present invention relates to the technical field of gear boxes, and in particular, to a micro gear box and its output shaft.

Background technique

At present, micro gearboxes with small size and high reduction ratio are used more and more widely, such as electronic door locks, communication equipment, precision instruments, medical equipment, smart homes, etc. As the final power output element of the gearbox, the output shaft is the part with the largest torque and force in the gearbox. The output shaft of the existing micro gearbox is designed with a cylindrical structure or a cylindrical structure with positioning trim. During installation, the output shaft is pressed into the last stage planet carrier of the gear box through axial pressure, and The interference fit prevents axial movement of the output shaft. However, when the gearbox operates for a long time, due to the action of alternating loads, the interference between the output shaft and the planet carrier gradually decreases. In this way, when the output shaft is subjected to axial force, axial force will easily occur. Movement affects the performance of the gearbox, and may even cause failures such as the output shaft coming out or the gearbox being axially stuck.

Contents of the invention

The object of the present invention is to overcome the above-mentioned deficiencies in the prior art and provide a micro gearbox and its output shaft, which avoids axial movement of the output shaft, improves the overall smoothness of the micro gear box operation, and thereby prolongs its service life. .

Embodiments of the present invention provide a micro gearbox, including a casing, a planet carrier disposed in the casing and abutting against the inner end surface of its output end, and a planet carrier extending through the output end of the casing and connected to the planet. The output shaft is rotated and positioned by the frame. The output shaft includes a shaft body and a positioning part coaxially provided at the rear end of the shaft body. The positioning part and the planet carrier are along the central axis of the output shaft and toward the The outer end of the shaft body is limited in the direction, and the outer end of the shaft body and the outer end surface of the output end are limited in the direction along the central axis and toward the tail end of the shaft body.

Further, both the shaft body and the positioning part are cylindrical, and the shaft diameter of the positioning part is larger than the shaft diameter of the shaft body.

Further, there is a mounting hole at the center of the planet carrier, a sinking groove is provided at the inner edge of the mounting hole, and a step adapted to the sinking groove is protruding from the outer periphery of the positioning part. The upper part is inserted into the mounting hole, and the step is received in the sinking groove and forms an axial movement limit toward the outer end of the shaft body.

Furthermore, the outer peripheral wall of the positioning portion has a mounting cut edge, and the inner wall of the mounting hole has a positioning cut edge. The mounting cut edge is parallel to the positioning cut edge to form a rotational positioning.

Furthermore, a bearing is provided in the opening of the output end, and the shaft body is rotatably installed in the bearing.

Further, the outer circumference of the outer end of the shaft body is provided with a snap ring groove, and the snap ring groove is provided with a snap ring. The snap ring resists the outer end surface of the output end of the housing and forms a snap ring facing the shaft. The axial movement limit of the tail end of the body.

Further, the outer end of the shaft body is covered with a gasket, and the gasket is sandwiched between the snap ring and the outer end surface of the output end of the housing.

Furthermore, the outer peripheral wall of the outer end of the shaft body has an output cut edge for transmission connection.

Further, the micro gearbox further includes a planet gear connected to the planet carrier, a motor gear meshing with the planet gear, and an end cover covering the rear end of the housing.

An embodiment of the present invention provides an output shaft for use in a micro gearbox. The micro gearbox includes a housing, and a planet carrier disposed in the housing and close to the inner end surface of its output end. The output shaft Penetrated in the output end of the housing and rotated with the planet carrier, the output shaft includes a shaft body and a positioning portion coaxially disposed at the rear end of the shaft body. The positioning portion is connected to the planet carrier. There is a limited fit between them along the central axis of the output shaft and toward the outer end of the shaft body, and between the outer end of the shaft body and the outer end surface of the output end along the central axis and toward the shaft body. The direction limit fit of the tail end.

Based on the above technical solution and compared with the existing technology, the embodiment of the present invention proposes a micro gearbox and its output shaft, in which the output shaft includes a shaft body and a positioning portion coaxially provided at the rear end of the shaft body. The output shaft Through the cooperation between its positioning part and the planet carrier limiter, a movement limiter is formed along its central axis toward its outer end. In this way, the problem of the output shaft moving to the outside of the gearbox and causing disengagement is avoided. At the same time, the output shaft passes through The outer end of the shaft body cooperates with the outer end face limit of the output end of the housing to form a movement limit along its central axis toward its tail end. This prevents the output shaft from moving into the gear box and causing the gear box to become axially stuck. This effectively improves the overall operation stability of the micro gearbox and extends its service life. Moreover, the micro gearbox has a simple structure, convenient processing and assembly, and at the same time, its output shaft has good versatility. It can be applied to both ordinary diameter gearboxes and micro-diameter gearboxes.

Description of the drawings

Figure 1 is a schematic three-dimensional structural diagram of a micro gearbox proposed in an embodiment of the present invention;

Figure 2 is a schematic cross-sectional structural diagram of the micro gearbox proposed by the embodiment of the present invention;

Figure 3 is a partial schematic diagram of the cross-sectional structure of the micro gearbox proposed by the embodiment of the present invention;

FIG. 4 is a schematic three-dimensional structural diagram of the output shaft proposed by the embodiment of the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention and are not intended to limit the present invention.

It should be noted that when an element is referred to as being "mounted" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is said to be "connected to" another element, it can be directly connected to the other element or intervening elements may also be present.

In addition, it should be noted that the terms left, right, up, and down in the embodiments of the present invention are only relative concepts or refer to the normal use state of the product, and should not be considered to be limiting. sexual. The implementation of the present invention is described in detail below with reference to specific embodiments.

As shown in Figures 1 to 4, an embodiment of the present invention proposes a micro gearbox. The micro gearbox may include a housing 1, a planet carrier 2 and an output shaft 3. The housing 1 has an opening at the front end and an opening at the rear end. A hollow shell, here, the front end of the shell 1 is the output end 11, the planet carrier 2 is arranged in the shell 1 and is close to the inner end surface of the output end 11, the output shaft 3 is passed through the output end 11 of the shell 1, and the The rear end of the output shaft 3 extends into the housing 1 and is rotated and positioned with the planet carrier 2. In this way, the axial rotation of the planet carrier 2 can drive the output shaft 3 to rotate axially. Specifically, the output shaft 3 may include a shaft body 31 and a positioning part 32, and the positioning part 32 is coaxially provided at the rear end of the shaft body 31. Inside the housing 1 of the micro gearbox, the positioning portion 32 of the output shaft 3 is limitedly engaged with the planet carrier 2, specifically along the central axis of the output shaft 3 and toward the outer end of its shaft body 31. At the same time, On the outside of the housing 1 of the micro gearbox, the outer end of the shaft body 31 of the output shaft 3 is limitedly matched with the outer end surface of the output end 11 of the housing 1, specifically along the central axis of the output shaft 3 and toward the end of the shaft body 31 End direction limit fit.

As mentioned above, the output shaft 3 of the micro gearbox proposed by the embodiment of the present invention includes a shaft body 31 and a positioning part 32 coaxially provided at the rear end of the shaft body 31. Here, the output shaft 3 communicates with the planet carrier through its positioning part 32. 2 limit fit, forming a movement limit along its central axis toward its outer end. In this way, the problem of the output shaft 3 moving to the outside of the gear box and coming out is avoided. At the same time, the output shaft 3 passes through the outside of its shaft body 31. end cooperates with the outer end face limit of the output end 11 of the housing 1 to form a movement limit along its central axis toward its tail end. In this way, the output shaft 3 is prevented from moving into the gear box and causing axial jamming of the gear box. This effectively improves the overall smooth operation of the micro gearbox and extends its service life. Moreover, the micro gearbox has a simple structure, convenient processing and assembly, and at the same time, its output shaft 3 is versatile. Well, it can be applied to both ordinary diameter gearboxes and micro-diameter gearboxes.

Furthermore, in the embodiment of the present invention, both the above-mentioned shaft body 31 and the above-mentioned positioning part 32 are preferably cylindrical, and the shaft diameter of the positioning part 32 is larger than the shaft diameter of the shaft body 31 . In this way, by designing the shaft body 31 and the positioning part 32 into a cylindrical shape and making the shaft diameter of the positioning part 32 larger than the shaft diameter of the shaft body 31 , the assembly and positioning of the output shaft 3 and the planet carrier 2 are more convenient. Of course, according to the actual situation and specific needs, in other embodiments of the present invention, the above-mentioned shaft body 31 and positioning portion 32 can also have other shapes, which are not uniquely limited here.

Further, in the embodiment of the present invention, there is a mounting hole 20 at the center of the planet carrier 2, and the mounting hole 20 is adapted to the positioning portion 32 at the rear end of the output shaft 3. Here, the positioning portion 32 is accommodated in the A rotation positioning is formed in the mounting hole 20, so that when the planet carrier 2 rotates axially, it can drive the output shaft 3 to rotate axially. Of course, according to the actual situation and specific needs, in other embodiments of the present invention, the above-mentioned planet carrier 2 can also be positioned, connected and matched with the output shaft 3 in other ways, which is not the only limitation here.

Further, in the embodiment of the present invention, a countersunk groove 200 is formed on the inner edge of the mounting hole 20 , and a step 321 adapted to the countersunk groove 200 is protruding from the outer periphery of the positioning portion 32 . The step 321 is accommodated in the sinking platform groove 200. At the same time, the bottom of the sinking platform groove 200 resists the movement of the step 321 toward the outer end of the mounting hole 20. In this way, an axial movement limiter toward the outer end of the shaft body 31 is formed. , that is to say, the step 321 cooperates with the countersunk groove 200 to prevent the output shaft 3 from moving outside the gear box. In addition, there is an avoidance gap between the inner wall of the countersunk groove 200 and the outer peripheral wall of the step 321 , and the end surface of the positioning portion 32 does not exceed the inner surface of the planet carrier 2 , that is, the rear end surface of the output shaft 3 does not exceed the inner surface of the planet carrier 2 . On the inner side, in this way, the assembly of the positioning part 32 and the planet carrier 2 is not only compact, but also simple and convenient to install. Of course, according to the actual situation and specific needs, in other embodiments of the present invention, the positioning portion 32 of the output shaft 3 and the planet carrier 2 can also be limited in other ways, which is not limited here.

In the embodiment of the present invention, the outer peripheral wall of the positioning portion 32 has a mounting cut edge 322. Here, the mounting cut edge 322 is a plane. Correspondingly, the inner wall of the mounting hole 20 of the planet carrier 2 has a positioning cut edge (not shown in the drawing) adapted to the mounting cut edge 322 . After assembly, the positioning part 32 is accommodated in the mounting hole 20 , and the mounting cut edge 322 on the outer peripheral wall of the positioning part 32 is parallel to the positioning cut edge on the inner wall of the mounting hole 20 , so that the positioning part 32 and the planet carrier 2 Create rotational positioning. Of course, according to the actual situation and specific needs, in other embodiments of the present invention, the positioning portion 32 of the output shaft 3 can also be rotated and positioned with the planet carrier 2 in other ways, such as key connection, etc., which is not limited here. .

In the embodiment of the present invention, a bearing 4 is provided in the opening of the output end 11 , and the shaft body 31 of the output shaft 3 is rotatably installed in the bearing 4 . By disposing the bearing 4 in the opening of the output end 11 and rotatably inserting the shaft body 31 of the output shaft 3 into the bearing 4, the rotational friction of the output shaft 3 is effectively reduced and the miniature gearbox is improved. overall performance.

In the embodiment of the present invention, a snap ring groove 310 is provided on the outer circumference of the outer end of the shaft body 31 , and a snap ring 5 is clamped in the snap ring groove 310 , and the snap ring 5 resists the output end of the housing 1 The outer end surface of 11 blocks the axial movement of the shaft body 31 toward its rear end. In this way, an axial movement limiter toward the rear end of the shaft body 31 is formed. That is to say, the blocking and limiting cooperation between the snap ring 5 and the outer end surface of the output end 11 prevents the output shaft 3 from moving into the gear box, thereby preventing the micro gear box from becoming axially stuck. Of course, depending on the actual situation and specific needs, in other embodiments of the present invention, the snap ring 5 can directly resist the outer end surface of the output end 11, or indirectly resist the outer end surface of the output end 11. In addition, the above-mentioned output shaft 3 The positioning fit between the shaft body 31 and the output end 11 can also be limited in other ways, which is not limited here.

Further, in the embodiment of the present invention, the outer end of the shaft body 31 is covered with a gasket 6, and the gasket 6 is sandwiched between the snap ring 5 and the outer end surface of the output end 11 of the housing 1 . That is to say, the snap ring 5 is installed in the snap ring groove 310, and the snap ring 5 is located outside the outer end surface of the output end 11 of the housing 1. In order to reduce friction, a pad is installed between the snap ring 5 and the outer end surface of the output end 11. In this way, the snap ring 5, the gasket 6 and the outer end surface of the output end 11 work together to prevent the output shaft 3 from moving into the gear box. Of course, according to the actual situation and specific needs, in other embodiments of the present invention, the friction between the gasket 6 and the outer end surface of the output end 11 can also be reduced in other ways, which is not the only limitation here.

In the embodiment of the present invention, the outer peripheral wall of the outer end of the shaft body 31 is provided with an output trimming edge 311, which is used for transmission connection with other external equipment to achieve power transmission. Here, the output trimming edge 311 and the above-mentioned mounting trimming edge 322 are both used to transmit torque when the output shaft 3 rotates. Of course, according to the actual situation and specific needs, in other embodiments of the present invention, the transmission connection between the outer end of the shaft body 31 and other external equipment can also be realized through other means, such as key connection, etc., which is not uniquely limited here.

Further, in the embodiment of the present invention, the above-mentioned micro gearbox also includes a planetary gear 7, a motor gear 8 and an end cover 9, wherein the end cover 9 covers the opening at the rear end of the above-mentioned housing 1, and the end cover 9 is connected with the outer casing 1. 1 is covered to form an inner cavity, in which the above-mentioned planet carrier 2, planet gear 7 and motor gear 8 are arranged, and the planet gear 7 is movably connected to the planet carrier 2, and the motor gear 8 meshes with the planet gear 7. In this way, the motor gear 8 rotates and drives the planetary gear 7 meshed with it to rotate. The planetary gear 7 drives the planet carrier 2 to rotate, and the planet carrier 2 drives the output shaft 3 to rotate. Of course, depending on the actual situation and specific needs, in other embodiments of the present invention, the micro gearbox may also include other components, which are not limited here.

In the embodiment of the present invention, when the above-mentioned micro gearbox is installed, first the positioning part 32 at the rear end of the output shaft 3 is installed in the mounting hole 20 of the planet carrier 2, and then the bearing 4 is installed at the output end 11 of the housing 1. In the output hole (that is, the opening), then pass the outer end of the shaft body 31 of the output shaft 3 through the bearing 4, then install other parts of the micro gearbox, and finally install a gasket on the outer end of the shaft body 31 of the output shaft 3 6 and snap ring 5 to complete the installation of output shaft 3.

As shown in Figures 1 to 4, an embodiment of the present invention also proposes an output shaft 3, which is used in the above-mentioned micro gearbox. The micro gearbox may include a housing 1, a planet carrier 2 and the output shaft 3, where , the housing 1 is a hollow housing with an opening at the front end and an opening at the rear end. Here, the front end of the housing 1 is the output end 11. The planet carrier 2 is arranged in the housing 1 and is close to the inner end surface of the output end 11. The output shaft 3 passes through It is located in the output end 11 of the housing 1, and the rear end of the output shaft 3 extends into the housing 1 and is rotated with the planet carrier 2. In this way, the axial rotation of the planet carrier 2 can drive the output shaft 3 to rotate axially. Specifically, the output shaft 3 may include a shaft body 31 and a positioning part 32. The positioning part 32 is coaxially disposed at the rear end of the shaft body 31. The positioning part 32 of the output shaft 3 is in limited fit with the planet carrier 2, specifically along the The central axis of the output shaft 3 is limited and matched in the direction of the outer end of its shaft body 31. At the same time, the outer end of the shaft body 31 of the output shaft 3 is limited and matched with the outer end surface of the output end 11 of the housing 1, specifically along the output shaft 3 The central axis is limited and fitted toward the direction of the tail end of its shaft body 31.

Based on the above technical solution, the output shaft proposed in the embodiment of the present invention, through its positioning portion 32 and the planet carrier 2, forms a movement limit along its central axis toward its outer end, thereby preventing the output shaft 3 from moving toward the gear. The problem of disengagement occurs due to external movement of the box, and the outer end of its shaft body 31 is matched with the outer end surface of the output end 11 of the housing 1 to form a movement limit along its central axis toward its tail end, thus avoiding the problem of output The problem of axial jamming of the gearbox occurs when the shaft 3 moves to the inside of the gearbox, which effectively improves the overall stability of the micro gearbox and extends its service life. Moreover, the output shaft 3 has good versatility and can be used It is suitable for ordinary diameter gearboxes and also for micro-diameter gearboxes.

The above-described embodiments are only specific implementations of the present invention, but the protection scope of the present invention is not limited thereto. Any person familiar with the technical field can easily think of various equivalents within the technical scope disclosed by the present invention. Modifications, replacements and improvements, etc., these modifications, replacements and improvements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims (8)

1. A micro gearbox, including a casing, a planet carrier disposed in the casing and abutting against the inner end surface of its output end, and an output shaft extending through the output end of the casing and positioned in rotation with the planet carrier. , characterized in that the output shaft includes a shaft body, and a positioning part coaxially provided at the rear end of the shaft body, and the positioning part and the planet carrier are along the central axis of the output shaft and toward the The outer end of the shaft body is limited in the direction, and the outer end of the shaft body and the outer end surface of the output end are limited in the direction along the central axis and toward the tail end of the shaft body; the shaft body and the The positioning parts are all cylindrical, and the shaft diameter of the positioning part is larger than the shaft diameter of the shaft body; there is a mounting hole at the center of the planet carrier, and a sinking groove is provided at the inner edge of the mounting hole. The outer periphery of the positioning part is convexly provided with a step adapted to the sinking platform groove. The positioning part is penetrated in the mounting hole, and the step is accommodated in the sinking platform groove and formed toward the axis. The axial movement of the outer end of the body is limited; there is an avoidance gap between the inner wall of the sinking groove and the outer peripheral wall of the step, and the end surface of the positioning part does not exceed the inner surface of the planet carrier. 2. The micro gearbox according to claim 1, wherein the outer peripheral wall of the positioning portion has a mounting trim, the inner wall of the mounting hole has a positioning trim, and the mounting trim is parallel to the mounting hole. A rotational positioning is formed on the positioning cut edge. 3. The micro gearbox according to claim 2, wherein a bearing is provided in the opening of the output end, and the shaft body is rotatably installed in the bearing. 4. The micro gearbox according to claim 1, characterized in that a snap ring groove is provided on the outer circumference of the outer end of the shaft body, and a snap ring is clamped on the snap ring groove, and the snap ring resists the The outer end surface of the output end of the housing also forms an axial movement limiter toward the rear end of the shaft body. 5. The micro gearbox according to claim 4, wherein a gasket is set on the outer end of the shaft body, and the gasket is sandwiched between the snap ring and the output end of the housing. between end faces. 6. The micro gearbox according to any one of claims 1 to 5, characterized in that the outer peripheral wall of the outer end of the shaft body has an output cut edge for transmission connection. 7. The micro gearbox according to any one of claims 1 to 5, wherein the micro gear box further includes a planet gear connected to the planet carrier, a motor gear meshing with the planet gear, and An end cap covering the rear end of the housing. 8. Output shaft, used in a micro gearbox. The micro gearbox includes a casing, and a planet carrier arranged in the casing and close to the inner end surface of the output end. The output shaft penetrates the casing. The output end of the shaft is rotated and positioned with the planet carrier. The characteristic is that the output shaft includes a shaft body and a positioning part coaxially provided at the rear end of the shaft body. There is a gap between the positioning part and the planet carrier. The space between the outer end of the shaft body and the outer end surface of the output end is along the central axis and toward the rear end of the shaft body. direction limit fit; both the shaft body and the positioning part are cylindrical, and the shaft diameter of the positioning part is larger than the shaft diameter of the shaft body; there is a mounting hole at the center of the planet carrier, and the mounting hole A sinking platform groove is provided on the inner edge of the positioning part, and a step adapted to the sinking platform groove is protruding from the outer periphery of the positioning part. The positioning part is penetrated in the mounting hole, and the step is accommodated in An axial movement limiter is formed in the sinking platform groove toward the outer end of the shaft body; there is a space avoidance gap between the inner wall of the sinking platform groove and the outer peripheral wall of the step, and the end surface of the positioning portion does not exceed the planet carrier the inner side of.