Low-noise motor

Abstract

The invention discloses a low-noise motor, which comprises a casing, a rotating shaft arranged in the casing, a stator sleeved outside the rotating shaft and connected with the casing, and two rotors positioned between the rotating shaft and the stator and used for driving the rotating shaft to rotate, and is characterized in that the number of the rotors is two, and the two rotors are sequentially arranged along the axial direction; and the relative positions of the two rotors in the circumferential direction are adjustable, a heat dissipation channel is arranged in the first rotor, two groups of heat dissipation channels are arranged in the second rotor, and the two groups of heat dissipation channels in the second rotor are alternately communicated with the heat dissipation channel in the first rotor along with the change of the circumferential positions of the two rotors. According to the low-noise motor provided by the invention, the heat dissipation effect of the position, close to the rear end, in the motor can be improved on the basis of not increasing noise, so that the overall heat dissipation effect of the motor is good.

Description

Technical Field

[0001] The invention relates to the technical field of motors, in particular to a low-noise motor. Background Art

[0002] Motor heat dissipation is a technical issue widely discussed in the motor industry. The use of air cooling in the motor to dissipate heat inside the motor is a relatively mature and widely used heat dissipation method. However, in some types of motors, due to the limitation of the installation space where the motor is located, only one end can be left for air inlet and outlet. For example, the pedal part of the existing treadmill design is increasingly tending to be flat, so after installation, this type of treadmill motor can only leave space for installing the air inlet and outlet at the front end part of the exposed shaft. For such motors with air inlet and outlet at one end, the internal heat dissipation problem is particularly obvious. The position of the rotor inside the motor close to the front air inlet has a good heat dissipation effect, and the rear end position away from the air inlet has a poor heat dissipation effect. For this reason, the prior art can only improve the overall heat dissipation effect by improving the air intake efficiency, so that the rear end position of the motor can also meet the heat dissipation requirements. However, this approach to improving the air intake efficiency is bound to increase the fan noise, which is a common technical problem in existing treadmill motors. The applicant has proposed a low-noise motor for a treadmill with a publication number of CN108880105A for reducing the noise of the treadmill motor, but the motor still has the problem of poor heat dissipation effect in the rear end of the motor in the prior art. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art to at least a certain extent: to provide a low-noise motor which can improve the heat dissipation effect near the rear end of the motor without increasing the noise, thereby improving the overall heat dissipation effect of the motor.

[0004] To this end, an object of the present invention is to provide a low-noise motor, which includes a casing, a rotating shaft is arranged in the casing, a stator is sleeved outside the rotating shaft and connected to the casing, and a rotor is located between the rotating shaft and the stator for driving the rotating shaft to rotate, characterized in that: there are two rotors, the two rotors are arranged in sequence along the axial direction, and the relative positions of the two rotors along the circumferential direction are adjustable, the first rotor has a heat dissipation channel, and the second rotor has two groups of heat dissipation channels, and the two groups of heat dissipation channels in the second rotor are alternately connected to the heat dissipation channels in the first rotor as the circumferential positions of the two rotors change.

[0005] The above technical solution has the following advantages or beneficial effects: First, the rotor adopts a dual-rotor structure design, so that the heat dissipation cold air sent from the heat dissipation channel of the first rotor can alternately pass through different groups of heat dissipation channels of the second rotor. Therefore, without changing the air intake efficiency in the heat dissipation channel of the first rotor, by reciprocating the second rotor, the two groups of heat dissipation channels in the second rotor alternately pass through the heat dissipation air, thereby improving the heat dissipation effect of the second rotor.

[0006] According to an example of the present invention, the two rotors are respectively provided with rotor windings, and the housing is provided with a controller for changing the current of each rotor winding. The controller can change the current passing through the rotor windings on the two rotors, thereby changing the driving force of the two rotors. With the change of the driving force, the relative position between the two rotors changes, thereby being able to well control the relative position of the two rotors without adding additional driving components, and is suitable for adjusting the relative position of the two rotors during the high-speed rotation of the rotor.

[0007] According to an example of the present invention, the end faces of the two rotors are in contact with each other, and a limiting member for limiting the rotational travel of any one rotor relative to the other rotor is provided between the two rotors.

[0008] According to an example of the present invention, the limiting member is a boss fixed on one of the two rotors, and a slide groove matching the boss is provided on the end surface of the other rotor. The boss and the slide groove are slidably matched. When the rotor drives the boss to rotate and abuts against the two ends of the slide groove, the heat dissipation channel in the first rotor is respectively connected with the two groups of heat dissipation channels in the other rotor.

[0009] According to an example of the present invention, the heat dissipation channel in the rotor axially penetrates both ends of the rotor and extends circumferentially in a spiral shape. By designing the heat dissipation channel in a spiral shape, noise can be well reduced.

[0010] According to an example of the present invention, a heat dissipation blade for supplying air into the heat dissipation channel is provided at an end of the first rotor facing away from the second rotor, and the heat dissipation blade is connected to the first rotor.

[0011] According to an example of the present invention, a plurality of return air channels are provided in the rotor, and the return air channels are arranged in the circumferential direction and are radially located outside the heat dissipation channel.

[0012] According to an example of the present invention, auxiliary blades are respectively provided at the positions of the air outlets of each return air channel on the first rotor, the auxiliary blades are connected to the first rotor, and the auxiliary blades are configured to drive the hot air at the air outlet to flow away from the rotor during the rotation of the first rotor.

[0013] According to an example of the present invention, an annular baffle is provided on the end surface of the first rotor facing away from the second rotor and located between the heat dissipation channel and the return air channel, and the baffle divides the cavity where the end surface of the first rotor is located into an air inlet cavity and an air outlet cavity, the heat dissipation channel is connected with the air inlet on the casing through the air inlet cavity, and the return air channel is connected with the air outlet on the casing through the air outlet cavity.

[0014] According to an example of the present invention, a rear cavity is provided in the casing at a position where the end of the second rotor is away from the first rotor, and a plurality of heat dissipation fins connected to the casing are provided in the rear cavity, the two groups of heat dissipation channels and the return air channel on the second rotor are respectively connected to the rear cavity, and the heat dissipation fins are arranged on the airflow path between the heat dissipation channel and the return air channel.

[0015] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the low-noise motor of the present invention.

[0017] Figure 2 for Figure 1 Schematic cross-sectional view along the “AA” direction.

[0018] Figure 3 for Figure 1 Schematic cross-sectional view in the "BB" direction.

[0019] Figure 4 for Figure 1 Schematic cross-sectional view in the “CC” direction.

[0020] Among them, 1. casing; 2. rotating shaft; 3. stator; 4. rotor; 5. boss; 6. slide slot; 7. heat dissipation blade; 8. auxiliary blade; 9. baffle; 10. air inlet chamber; 11. air outlet chamber; 12. rear chamber. DETAILED DESCRIPTION

[0021] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0022] A low noise motor according to an embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

[0023] In the heat dissipation of the motor, especially when only the front end of the motor can enter and exit the air, when the rotor in the motor is cooled by air cooling, the part of the rotor close to the front end of the motor contacts the cooling air first, so the cooling effect is good, while the part close to the rear end has a poor heat dissipation effect because the temperature of the cooling air continues to rise and the temperature difference between the rotor and the cooling air decreases. In addition, the part close to the channel where the cooling air is located has a good heat dissipation effect, while the part of the rotor far away from the channel has a poor heat dissipation effect. As a result, the closer the entire rotor is to the rear end and the farther it is from the cooling channel, the higher the temperature area is formed, and finally the temperature uniformity of different positions of the entire rotor is poor. With the long-term use of the motor, the fixed local high-temperature area is prone to damage, and the coils of the rotor winding on the rotor also break in this high-temperature area before other positions.

[0024] Therefore, for the air-cooled motor with air intake at one end, how to improve the overall temperature uniformity of the rotor without changing the air intake volume is an important direction for improving the heat dissipation effect without increasing noise. Figure 1 As shown, it includes a casing 1, the right end of the casing 1 is the front end of the motor, the left end is the rear end of the motor, a rotating shaft 2 is arranged inside the casing 1, a stator 3 is sleeved outside the rotating shaft 2 and connected to the casing 1, and a rotor 4 is located between the rotating shaft 2 and the stator 3 for driving the rotating shaft 2 to rotate, the front end of the rotating shaft 2 protrudes outside the front end of the casing 1, the rotor 4 is fixed to the rotating shaft 2, and the rotor 4 and the stator 3 are rotatably matched, and the characteristic is that: the rotor 4 is two, the two rotors 4 are arranged in sequence along the axial direction, and the relative positions of the two rotors 4 along the circumferential direction are adjustable, such as Figure 1As shown, the rotor 4 on the right is the first rotor, and the rotor 4 on the left is the second rotor, wherein the first rotor 4 has a heat dissipation channel 4.1, and the second rotor 4 has two groups of heat dissipation channels 4.2. The two groups of heat dissipation channels 4.2 in the second rotor 4 are alternately connected to the heat dissipation channel 4.1 in the first rotor 4 as the circumferential positions of the two rotors 4 change. Since the relative positions of the two rotors 4 can be adjusted along the circumferential direction, the two rotors 4 have at least two working positions. When the two rotors 4 are in the first working position, the heat dissipation channel 4.1 in the first rotor 4 is connected with the first group of heat dissipation channels 4.2a in the second rotor 4, so that the air in the cavity on the right side of the rotor 4 in the casing 1 can flow to the cavity on the left side of the rotor 4 in the casing 1 through the heat dissipation channels on the two rotors 4 in sequence, thereby completing the heat dissipation of the two rotors 4; when the two rotors 4 are switched from the first working position to the second working position, the heat dissipation channel 4.1 in the first rotor 4 is connected with the second group of heat dissipation channels 4.2b in the second rotor 4, so that the air in the cavity on the right side of the rotor 4 in the casing 1 can flow to the cavity on the left side of the rotor 4 in the casing 1 through the heat dissipation channel 4.1 of the first rotor 4 and the second group of heat dissipation channels 4.2b in the second rotor 4 in sequence, thereby completing the heat dissipation of the two rotors 4. In this embodiment, since the second rotor 4 has two groups of heat dissipation channels 4.2, and the two groups of heat dissipation channels 4.2 pass heat dissipation air alternately, when the rotor temperature at the position of any group of heat dissipation channels 4.2 is too high, the heat dissipation air can enter the heat dissipation channel 4.2 with higher temperature by rotating the second rotor, thereby finally making the overall temperature uniformity of the second rotor 4 better.

[0025] The air intake volume in the above embodiment refers to the total volume of heat dissipation air passing through all heat dissipation channels 4.1 in the first rotor per unit time.

[0026] like Figure 3 As shown, the two groups of heat dissipation channels 4.2 on the second rotor 4 are multiple heat dissipation channels 4.2 arranged alternately along the circumferential direction, and each heat dissipation channel in the first group of heat dissipation channels 4.2a and each heat dissipation channel in the second group 4.2b are arranged alternately along the circumferential direction. Specifically, there are six heat dissipation channels on the first rotor 4, and the six heat dissipation channels 4.1 are evenly arranged along the circumferential direction; there are two groups of heat dissipation channels 4.2 on the second rotor 4, and each group of heat dissipation channels 4.2 is composed of six heat dissipation channels, and each heat dissipation channel in the first group of heat dissipation channels 4.2a and each heat dissipation channel in the second group 4.2b are arranged alternately along the circumferential direction.

[0027] Preferably, the two rotors 4 are respectively provided with rotor windings (not shown in the figure), which are coils wound on the rotor 4. When the coils are energized, they can generate a driving force to drive the rotor 4 to rotate. The housing 1 is provided with a controller for changing the current of each rotor winding. The controller adjusts the current of the rotor windings on the two rotors, thereby changing the driving force for the two rotors to rotate in the same stator. When the current of the rotor winding on the first rotor 4 is greater than the current of the rotor winding on the second rotor 4, the first rotor has a faster movement trend than the second rotor, thereby making the two rotors in the first working position. Similarly, when the current of the rotor winding on the first rotor 4 is less than the current of the rotor winding on the second rotor 4, the second rotor has a faster movement trend than the first rotor, thereby making the two rotors in the second working position. Therefore, the relative circumferential positions of the two rotors can be changed during the normal operation of the rotors only by the controller, that is, the two rotors can switch freely between the two working positions, thereby realizing that the two groups of heat dissipation channels 4.2 on the second rotor are alternately connected with the heat dissipation channels 4.1 on the first rotor in different working positions. Compared with the adjustment of the circumferential position between the two rotors by an additional driving component, the structure of this embodiment is simpler, and the controller can be integrated in the original driving control board of the motor in a modular manner, thereby making the overall structure more reliable. It should be understood that the rotation speed of the rotor of the motor is generally high during normal operation. Under this high-speed rotation condition, the installation requirements for the driving components are high, and the probability of failure is also increased. For this reason, in this embodiment, the control of the relative position of the two rotors can be achieved only by adjusting the distribution of the current passing through the rotor windings on each rotor, which is more reliable and stable.

[0028] Based on the preference of the above embodiment, the end faces of the two rotors 4 are in contact with each other, and a limiter is provided between the end faces of the two rotors 4 that are in contact with each other, and the limiter is used to limit the rotation stroke of any rotor 4 relative to the other rotor 4. That is, when any rotor 4 rotates forward to the limit position and reversely to the limit position relative to the other rotor 4, it can be in the first working position and the second working position respectively.

[0029] Specifically, the limiting member is a boss 5 fixed on one of the two rotors 4, and a slide groove 6 matching the boss 5 is provided on the end surface of the other rotor 4. The boss 5 and the slide groove 6 are slidably matched. When the rotor 4 drives the boss 5 to rotate and abuts against the two ends of the slide groove 6, the heat dissipation channel in the first rotor 4 is respectively connected with the two groups of heat dissipation channels in the other rotor 4.

[0030] In the above embodiment, the cooling fan drives the cooling air to rotate as the rotor rotates, and enters each cooling channel driven by the blades. However, the cooling channel is vertical along the axial direction, and the cooling air driven by the circumferential rotation of the cooling fan is a spiral airflow. At this time, the airflow will form a large wind noise at the air inlet of the cooling channel, which is also an important part of the noise generated by the cooling fan in the existing motor. For this reason, the preferred embodiment of this embodiment is that the cooling channel in the rotor 4 axially penetrates both ends of the rotor 4 and extends circumferentially in a spiral shape. That is, the cooling channels in the two rotors both adopt a spiral structure, and the cooling channel extends along an axis parallel to the center line of the rotor and rotates circumferentially around the center line of the rotor to form a spiral cooling channel. The two ends of the cooling channel respectively penetrate the two end surfaces of the rotor 4. In this embodiment, since the entire cooling channel is spiral, and the rotation direction of the spiral cooling air channel matches the rotation direction of the rotor, the spiral airflow brought by the cooling fan can enter the cooling air channel more smoothly, thereby improving the noise of the airflow at the air inlet position of the cooling air channel.

[0031] For the specific example of the above-mentioned heat dissipation fan: the heat dissipation fan includes a plurality of heat dissipation blades 7, which are located at the end of the first rotor 4 away from the second rotor 4, and each heat dissipation blade 7 is evenly arranged along the circumference of the rotor 4, so that when each heat dissipation blade 7 rotates with the rotor 4, the heat dissipation air in the housing 1 is driven to enter from the corresponding heat dissipation channel, such as Figure 1 As shown, the heat dissipation blade 7 is connected to the right end of the first rotor 4 .

[0032] Based on the above preferred embodiment, the rotor 4 has a plurality of return air channels, which are arranged along the circumferential direction and radially outside the heat dissipation channel. Figure 2 As shown, the first rotor 4 has a return air channel 4.4, and the second rotor 4 has a return air channel 4.3, and the return air channels in the two rotors are connected to each other. Figure 3 As shown, the mating surfaces of the two rotors are concave to form an arc-shaped air cavity 4.5, and the return air channel 4.4 on the first rotor 4 and the return air channel 4.3 on the second rotor 4 are connected through the arc-shaped air cavity 4.5.

[0033] like Figure 2 As shown, auxiliary blades 8 are respectively provided at the positions of the air outlets of each return air channel 4.3 on the first rotor 4. The auxiliary blades 8 are connected to the first rotor 4, and the auxiliary blades 8 are arranged to drive the hot air at the air outlet to flow away from the rotor 4 during the rotation of the first rotor 4.

[0034] like Figure 1 and Figure 2As shown, an annular baffle 9 is provided on the end surface of the first rotor 4 facing away from the second rotor 4, between the heat dissipation channel and the return air channel, and the baffle 9 divides the cavity where the end surface of the first rotor 4 is located into an air inlet cavity 10 and an air outlet cavity 11, the heat dissipation channel is connected with the air inlet on the casing 1 through the air inlet cavity 10, and the return air channel is connected with the air outlet on the casing 1 through the air outlet cavity 11.

[0035] Based on the preference of the above embodiment, the housing 1 has a rear cavity 12 at the position where the end of the second rotor 4 is away from the first rotor 4, and the rear cavity 12 has a plurality of heat dissipation fins connected to the housing 1. The two groups of heat dissipation channels and the return air channel on the second rotor 4 are respectively connected to the rear cavity 12, and an airflow path is formed between the heat dissipation channel and the return air channel in the rear cavity 12, and the heat dissipation fins are arranged on the airflow path between the heat dissipation channel and the return air channel. The airflow path in this embodiment refers to a channel in the rear cavity 12 for the air flowing out of the heat dissipation channel to enter the return air channel, and the airflow flows in the channel to form an airflow path.

[0036] It should be noted here that in the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0037] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0038] In the present invention, 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 or an electrical connection; 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 invention can be understood according to specific circumstances.

[0039] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0040] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0041] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

[0042] For those skilled in the art, various changes and modifications will undoubtedly be obvious after reading the above description. Therefore, the attached claims should be regarded as covering all changes and modifications of the true intent and scope of the present invention. Any and all equivalent ranges and contents within the scope of the claims should be considered to still be within the intent and scope of the present invention.

Claims

1. A low-noise motor, comprising a housing (1), a rotating shaft (2) disposed in the housing (1), a stator (3) sleeved outside the rotating shaft (2) and connected to the housing (1), and a rotor (4) located between the rotating shaft (2) and the stator (3) for driving the rotating shaft (2) to rotate, characterized in that: There are two rotors (4), which are arranged in sequence along the axial direction, and the relative positions of the two rotors (4) along the circumferential direction are adjustable, wherein the first rotor (4) has a heat dissipation channel, and the second rotor (4) has two groups of heat dissipation channels, and the two groups of heat dissipation channels in the second rotor (4) are alternately connected to the heat dissipation channels in the first rotor (4) as the circumferential positions of the two rotors (4) change.

2. The low noise motor according to claim 1, characterized in that: The two rotors (4) are respectively provided with rotor windings, and the casing (1) is provided with a controller for changing the magnitude of the current of each rotor winding.

3. The low noise motor according to claim 2, characterized in that: The end surfaces of the two rotors (4) are in contact with each other, and a limiting member is provided between the two rotors (4) for limiting the rotational travel of any one rotor (4) relative to the other rotor (4).

4. The low noise motor according to claim 3, characterized in that: The stopper is a boss (5) fixed on one of the two rotors (4); a slide groove (6) matching the boss (5) is provided on the end surface of the other rotor (4); the boss (5) and the slide groove (6) are slidably matched; when the rotor (4) drives the boss (5) to rotate and abuts against two ends of the slide groove (6), the heat dissipation channel in the first rotor (4) is respectively connected with the two groups of heat dissipation channels in the other rotor (4).

5. The low noise motor according to claim 4, characterized in that: The heat dissipation channel in the rotor (4) axially penetrates both ends of the rotor (4) and extends circumferentially in a spiral shape.

6. The low noise motor according to claim 5, characterized in that: The end of the first rotor (4) facing away from the second rotor (4) is provided with a heat dissipation blade (7) for supplying air into the heat dissipation channel, and the heat dissipation blade (7) is connected to the first rotor (4).

7. The low noise motor according to claim 6, characterized in that: The rotor (4) has a plurality of return air channels therein, the return air channels being arranged in the circumferential direction and being located radially outside the heat dissipation channel.

8. The low noise motor according to claim 7, characterized in that: Auxiliary blades (8) are respectively provided at the positions of the air outlets of the converging channels on the first rotor (4); the auxiliary blades (8) are connected to the first rotor (4), and the auxiliary blades (8) are arranged to drive the hot air at the air outlet to flow in a direction away from the rotor (4) during the rotation of the first rotor (4).

9. The low noise motor according to claim 8, characterized in that: An annular baffle (9) is provided on the end surface of the first rotor (4) facing away from the second rotor (4) and located between the heat dissipation channel and the return air channel, the baffle (9) dividing the cavity where the end surface of the first rotor (4) is located into an air inlet cavity (10) and an air outlet cavity (11), the heat dissipation channel is connected to the air inlet on the casing (1) through the air inlet cavity (10), and the return air channel is connected to the air outlet on the casing (1) through the air outlet cavity (11).

10. The low noise motor according to claim 9, characterized in that: The casing (1) has a rear cavity (12) at a position where the end of the second rotor (4) is away from the first rotor (4), and the rear cavity (12) has a plurality of heat dissipation fins connected to the casing (1). The two groups of heat dissipation channels and the return air channel on the second rotor (4) are respectively connected to the rear cavity (12), and the heat dissipation fins are arranged on the airflow path between the heat dissipation channel and the return air channel.

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