Motor shaft for gear motor

Abstract

The motor shaft comprises a shaft body, a rotor connecting part, a bearing connecting end, a spline connecting end and a connecting part are sequentially arranged on the shaft body, the axial width of the bearing connecting end is at least one half of the axial width of the spline connecting end, and a spline formed through cold extrusion is arranged on the outer surface of the spline connecting end. According to the utility model, the structural design is reasonable, the spline forming mode is changed from the original milling cutter forming mode to the cold extrusion forming mode, the axial width of the spline connecting end is controlled within the effective length of the spline, and the ineffective length is removed, so that the axial width of the bearing connecting end is increased; the inner surface of the bearing is completely matched and connected with the outer surface of the bearing connecting end, so that the stress area of the bearing is increased, the assembly strength of the bearing is improved, the stability is improved, and the service life of the bearing is prolonged.

Description

Technical Field

[0001] The utility model relates to the field of motors, in particular to a motor shaft for a reduction motor. Background Art

[0002] An electric motor, commonly known as a "motor", is an electromagnetic device that converts or transmits electrical energy according to the law of electromagnetic induction. Existing electric motors mainly include a stator, a rotor, and a reduction mechanism. Among them, the motor shaft is pressed into the rotor and connected to the silicon steel sheet in the center hole of the rotor. The rotation of the motor shaft drives the rotor to rotate, which is the core of the powertrain of the motor.

[0003] Existing motor shafts are all provided with a bearing connection end for installing bearings and a spline connection end for meshing with planetary gears. The bearing connection end and the spline connection end are usually arranged adjacent to each other. Since the length of the milling cutter for forming the spline is limited, the axial width of the spline connection end is usually larger, resulting in a smaller axial width of the bearing connection end. As a result, when the bearing is pressed onto the bearing connection end, a portion of the inner surface of the bearing conflicts with the outer surface of the spline connection end, thereby reducing the connection area between the inner surface of the bearing and the outer surface of the bearing connection end, reducing the force-bearing area of ​​the bearing, reducing the assembly strength, reducing the stability, and shortening the service life of the bearing. According to relevant specifications, the axial width of the spline connection end, that is, the effective length of the spline, does not need to be so large. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a motor shaft for a reduction motor in view of the current status of the prior art.

[0005] The technical solution adopted by the utility model to solve the above technical problems is: a motor shaft for a reduction motor, including a shaft body, on which a rotor connecting part, a bearing connecting end, a spline connecting end and a connecting part are sequentially arranged, characterized in that the axial width of the bearing connecting end is at least one half of the axial width of the spline connecting end, and the outer surface of the spline connecting end is provided with a spline formed by cold extrusion.

[0006] Preferably, a bearing is pressed onto the bearing connecting end, and the inner surface of the bearing is cooperatively connected with the outer surface of the bearing connecting end.

[0007] Preferably, the spline comprises a plurality of spline teeth that are evenly arranged and extend along the axis of the shaft body, and the cross section of the spline teeth is in the shape of an involute cylindrical gear.

[0008] Preferably, the bottom of the spline teeth and the upper surface of the bearing connecting end are integrally formed.

[0009] Preferably, the spline teeth are flush with or lower than the end face of the bearing connection end.

[0010] Preferably, the rotor connection part is arranged in the middle of the shaft body, the outer surface of the rotor connection part is provided with the rotor, and the outer surface of the rotor connection part is evenly arranged with a plurality of spline grooves that cooperate with the rotor and are connected to the rotor along the axis direction of the shaft body.

[0011] Preferably, a bearing stopper is provided between the rotor connecting portion and the bearing connecting end, and the bottom surface of the bearing is in contact with the upper surface of the bearing stopper.

[0012] Compared with the prior art, the utility model has the advantages that: by changing the spline forming method from the original milling cutter forming to cold extrusion forming, the axial width of the spline connecting end is controlled within the effective length of the spline, and the invalid length is removed, thereby increasing the axial width of the bearing connecting end, making the inner surface of the bearing and the outer surface of the bearing connecting end fully matched and connected, increasing the force area of ​​the bearing, improving the assembly strength of the bearing, improving the stability, and extending the service life of the bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural schematic diagram of the utility model;

[0014] Figure 2 It is a schematic diagram of the cross-sectional structure of the utility model;

[0015] Figure 3 It is a schematic diagram of the cross-sectional structure of the utility model after the bearing is press-fitted.

[0016] Figure numerals: 1, shaft body; 2, rotor connecting part; 21, spline groove; 3, bearing connecting end; 4, spline connecting end; 41, spline; 42, spline teeth; 5, connecting part; 6, bearing; 7, bearing stopper. DETAILED DESCRIPTION

[0017] The following will disclose multiple embodiments of the present invention with drawings. For the purpose of clear description, many practical details will be described together in the following description. However, it should be understood that these practical details should not be used to limit the present invention. In other words, in some embodiments of the present invention, these practical details are not necessary. In addition, in order to simplify the drawings, some conventional structures and components will be depicted in a simple schematic manner in the drawings.

[0018] It should be noted that all directional indications in the embodiments of the present invention, such as up, down, left, right, front, back... are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0019] Moreover, some of the above-mentioned terms may be used to express other meanings besides indicating orientation or positional relationships. For example, the term "on" may also be used to indicate a certain dependency or connection relationship in certain circumstances. A person skilled in the art may understand the specific meanings of these terms in the present utility model according to the specific circumstances.

[0020] In addition, the terms "install", "set", "provided with", "connect", "connected", and "socketed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. The connection methods involved in this article are prior arts, without any improvement, and are all common knowledge of those skilled in the art. For those skilled in the art, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.

[0021] In addition, in the present utility model, the descriptions of "first", "second", etc. are only used for descriptive purposes, and do not specifically refer to the order or sequence, nor are they used to limit the present utility model. They are only used to distinguish components or operations described with the same technical terms, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0022] like Figures 1 to 3 As shown, the utility model provides a motor shaft for a reduction motor, including a shaft body 1, on which a rotor connecting portion 52, a bearing connecting end 3, a spline connecting end 4 and a connecting portion 5 are sequentially provided; specifically, the axial width of the bearing connecting end 3 is at least one-half of the axial width of the spline connecting end 4, and the outer surface of the spline connecting end 4 is provided with a spline 41 formed by cold extrusion.

[0023] A bearing 6 is pressed onto the bearing connection end 3 , and the inner surface of the bearing 6 is matched and connected with the outer surface of the bearing connection end 3 .

[0024] By changing the forming method of the spline 41 from the original milling cutter forming to cold extrusion forming, the axial width of the spline connecting end 4 is controlled while ensuring the effective use length of the spline 41, and the invalid length is removed, so that the axial width of the spline connecting end 4 is shortened, thereby increasing the axial width of the bearing connecting end 3, so that the inner surface of the bearing 6 and the outer surface of the bearing connecting end 3 are fully matched and connected; compared with the axial width of the spline connecting end 4 formed by the milling cutter is too large, the axial width of the bearing connecting end 3 is reduced, and a part of the inner surface of the bearing 6 pressed on the bearing connecting end 3 will contact the outer surface of the spline connecting end 4. The design of the utility model increases the effective force-bearing area of ​​the bearing 6, improves the assembly strength of the bearing 6, improves the stability, and extends the service life of the bearing 6.

[0025] Furthermore, the cold extrusion molding method is adopted, so that the spline 41 has a higher flatness after molding, and the stress concentration is reduced.

[0026] The spline 41 includes a plurality of spline teeth 42 that are evenly arranged and extend along the axis direction of the shaft body 1; specifically, the cross section of the spline teeth 42 is in the shape of an involute cylindrical gear.

[0027] The bottom of the spline teeth 42 and the upper surface of the bearing connection end 3 are integrally formed.

[0028] The tooth height of the spline teeth 42 is flush with or lower than the end surface of the bearing connection end 3 .

[0029] The rotor connection part 52 is arranged in the middle of the shaft body 1, and the rotor is connected to the outer surface of the rotor connection part 52; specifically, a plurality of spline grooves 21 that are matched with the rotor and connected are evenly arranged on the outer surface of the rotor connection part 52 extending along the axial direction of the shaft body 1.

[0030] A bearing stopper 7 is provided between the rotor connection portion 52 and the bearing connection end 3 ; specifically, the bottom surface of the bearing 6 is in contact with the upper surface of the bearing stopper 7 .

[0031] The connecting portion 5 is sleeved with a planetary gear, and the outer edges of the gears are meshed and connected with the spline teeth 42 .

[0032] The shaft body 1 is also provided with a fixing portion which plays a fixing role. The fixing portion is arranged on a side of the rotor connecting portion 52 away from the bearing connecting end 3 .

[0033] The advantages of the utility model are as follows: by changing the forming method of the spline 41 from the original milling cutter forming to cold extrusion forming, the axial width of the spline connecting end 4 is controlled within the effective length of the spline 41, and the invalid length is removed, thereby making the axial width of the bearing connecting end 3 larger, so that the inner surface of the bearing 6 and the outer surface of the bearing connecting end 3 are fully matched and connected, increasing the force-bearing area of ​​the bearing 6, improving the assembly strength of the bearing 6, improving the stability, and extending the service life of the bearing 6.

[0034] In the description of this specification, reference is made to the terms "one embodiment", "some embodiments", "examples", "specific examples", etc.

[0035] The description of "example" or "some examples" means that the specific features, structures, materials or characteristics described in combination with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0036] The standard parts used in the present invention can all be purchased from the market, and special-shaped parts can be customized according to the description in the specification and drawings. The specific connection methods of each part adopt conventional means such as mature bolts, rivets, welding, and bonding in the prior art, which will not be described in detail here.

[0037] The above contents are only preferred embodiments of the present invention. For ordinary technicians in this field, various changes and variations can be made in the specific implementation methods and application scopes based on the ideas of the present invention. The content of this specification should not be understood as a limitation on the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A motor shaft for a reduction motor, comprising a shaft body, on which a rotor connection portion, a bearing connection end, a spline connection end and a connection portion are sequentially arranged, characterized in that: The axial width of the bearing connection end is at least one-half of the axial width of the spline connection end, and the outer surface of the spline connection end is provided with a spline formed by cold extrusion.

2. A motor shaft for a reduction motor according to claim 1, characterized in that: A bearing is pressed onto the bearing connection end, and the inner surface of the bearing is matched and connected with the outer surface of the bearing connection end.

3. The motor shaft for a reduction motor according to claim 1, characterized in that: The spline comprises a plurality of spline teeth which are evenly arranged and extend along the axis direction of the shaft body, and the cross section of the spline teeth is in the shape of an involute cylindrical gear.

4. The motor shaft for a reduction motor according to claim 3, characterized in that: The bottom of the spline teeth and the upper surface of the bearing connection end are integrally formed.

5. The motor shaft for a reduction motor according to claim 3, characterized in that: The spline teeth are flush with or lower than the end face of the bearing connection end.

6. The motor shaft for a reduction motor according to claim 1, characterized in that: The rotor connection part is arranged in the middle of the shaft body, the outer surface of the rotor connection part is connected with the rotor, and the outer surface of the rotor connection part is evenly arranged with a plurality of spline grooves matched with the rotor extending along the axis direction of the shaft body.

7. The motor shaft for a reduction motor according to claim 2, characterized in that: A bearing stopper is provided between the rotor connection portion and the bearing connection end, and the bottom surface of the bearing is in contact with the upper surface of the bearing stopper.

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