Vibration motor with guide rail and rolling members and stopping magnet

Provided is a vibration motor, including: a housing having a receiving space; a vibrator received in the receiving space; and a coil configured to drive the vibrator to reciprocate; and a guide rail received in the receiving space and fixed to the housing. The vibrator includes a rolling friction portion corresponding to the guide rail, and the rolling friction portion comprises a mass block spaced apart from and opposite to the guide rail, and a plurality of rolling members connected between the mass block and the guide rail in a slidable way. Compared with the related art, the vibration motor provided by the present invention can effectively reduce a friction force and improve a performance thereof.

TECHNICAL FIELD

The present invention relates to the field of vibration motors, and particularly, to a vibration motor having a low friction coefficient and low noise.

BACKGROUND

A vibration motor is a component that converts electrical energy into mechanical energy by using a mechanism of generation of an electromagnetic force. The vibration motor is usually installed in a portable mobile device to generate a vibration feedback, such as a vibration feedback of a mobile phone or a game machine.

In the related art, the vibration motor includes a case having a receiving space, a vibrator received in the receiving space, and a coil configured to drive the vibrator to reciprocate.

However, the vibrator of the vibration motor known in the related art is in sliding contact with other components of the vibration motor during vibration, which may result in a great friction force between the vibrator and other components. In addition, during the friction process, friction noise will be generated, thereby greatly reducing the user experience of using the portable mobile device.

Therefore, it is necessary to provide an improved vibration motor to solve the problem described above.

SUMMARY

The problems in the related art are in that the vibrator of the vibration motor is in sliding contact with other components of the vibration motor during vibration, which may result in great friction force and friction noise to negatively affect the user experience. In view of the technical problems, the present invention provides a vibration motor having a low friction coefficient and low noise.

A vibration motor includes a housing having a receiving space; a vibrator received in the receiving space; a coil configured to drive the vibrator to reciprocate; and a guide rail received in the receiving space and fixed to the housing. The vibrator includes a rolling friction portion corresponding to the guide rail, and the rolling friction portion comprises a mass block spaced apart from and opposite to the guide rail, and a plurality of rolling members connected between the mass block and the guide rail in a slidable way.

As an improvement, the housing comprises a main body portion having a cylindrical shape and two end covers spaced apart from and opposite to each other, and the two end covers respectively cover openings at two ends of the main body portion to define the receiving space; the guide rail has a hollow structure and surrounds a sliding space, a cross-section of the guide rail along a direction perpendicular to a vibrating direction has the same shape as a cross-section of the main body portion along the direction perpendicular to the vibrating direction, and the mass block is located in the sliding space.

As an improvement, the mass block comprises a sliding surface spaced apart from and opposite to the guide rail and a plurality of recesses each formed by recessing from the sliding surface in a direction facing away from the guide rail; and each of the plurality of rolling members is at least partially received in a corresponding one of the plurality of recesses.

As an improvement, each of the plurality of rolling members is a ball, and the plurality of recesses is parallel to the vibrating direction.

As an improvement, the mass block further comprises a side surface connected to the sliding surface and perpendicular to the vibrating direction, the side surface faces towards one of the two end covers, the plurality of recesses extends to the side surface; the vibration motor further comprises a stopping sheet affixed to the side surface, and a projection of each of the plurality of recesses in the direction perpendicular to the vibrating direction at least partially overlaps a projection of the stopping sheet in the direction perpendicular to the vibrating direction.

As an improvement, a projection of the mass block in the direction perpendicular to the vibrating direction has a rectangular shape; the sliding surface comprises two first surfaces parallel to and spaced apart from each other, and two second surfaces connecting the first surfaces and parallel to and spaced apart from each other; and the plurality of recesses is formed by recessing from the two first surfaces and/or the two second surfaces.

As an improvement, the vibration motor further includes a stopper fixed to one of the two end covers, wherein the stopper comprises a first magnet fixed to the one end cover, and a magnetic conductive sheet fixed to a surface of the first magnet close to the mass block.

As an improvement, the vibrator further comprises an iron core located in a middle position thereof and second magnets fixed to two ends of the iron core; the iron core is located in a space surrounded by the coil and is spaced apart from the coil; and each of the second magnets is arranged between the rolling friction portion and the iron core.

As an improvement, each of the second magnets has a hollow structure, and comprises a magnet body portion and an accommodating space surrounded by the magnet body portion; the iron core comprises an iron core body portion and an iron core extending portion extending from the iron core body portion towards the rolling friction portion; and the iron core extending portion is received in the accommodating space.

As an improvement, the rolling friction portion further comprises a mass block extending portion extending from the mass block towards the iron core, and the mass block extending portion is received in the accommodating space.

As an improvement, the second magnets located at the two ends of the iron core have opposite magnetic poles.

As an improvement, each of the second magnets and the first magnet adjacent to the second magnet have a same magnetic pole.

As an improvement, a winding direction of the coil is parallel to a vibrating direction.

Compared with the related art, in the vibration motor according to the present invention, the rolling friction portion and the guide rail are provided, and the rolling friction portion includes the mass block spaced apart from the guide rail and a number of rolling members connected between the mass block and the guide rail in a slidable way, thereby providing the rolling friction between the vibrator and the case through the rolling members. The friction force between the vibrator and the guide rail is relatively low, and thus the noise is low, which effectively improves performance of the vibration motor.

DESCRIPTION OF EMBODIMENTS

The technical solutions in the embodiments of the present invention are described in detail with reference to the accompanying drawings. It should be noted that, the described embodiments are merely exemplary embodiments of the present invention, which shall not be interpreted as limitations to the present invention. Other embodiments, which are obtained by those skilled in the art without paying creative efforts according to the embodiments of the present invention, shall fall within the scope of the present invention.

With reference toFIG.1toFIG.3, the present invention provides a vibration motor100, which includes a housing10having a receiving space, a guide rail20and a stopper30that are received in the receiving space and fixed to the housing10, a vibrator40received in the receiving space, a coil50configured to drive the vibrator40to reciprocate, and a stopping sheet60fixed to the vibrator40.

The housing10includes a main body portion11having a cylindrical shape, and two end covers13opposite to and spaced apart from each other. The two end covers13respectively cover openings at two ends of the main body portion11to define the receiving space. The vibrator40is provided along an extending direction of the main body portion11, i.e., a direction from one end cover111to the other end cover111, and the vibrator50can vibrate along the extending direction of the main body portion11.

The guide rail20is formed as a hollow structure and encloses a sliding space21. A cross-section of the guide rail20along a direction perpendicular to a vibrating direction and a cross-section of the main body portion11along the direction perpendicular to the vibrating direction have the same shape. In this embodiment, for example, two guide rails20are provided, and the two guide rails20are respectively located at two ends of the main body portion11.

The stopper30is directly opposite to the vibrator40. The stopper30includes a first magnet31fixed to the end cover13, and a magnetic conductive sheet33fixed to a surface of the first magnet31close to the vibrator40. The stopper30is configured to supply a repulsive force to the vibrator40, so as to prevent the vibrator40from hitting the end cover13. In an example, two stoppers30are provided, and the two stoppers30are respectively provided at the two end covers13. By respectively providing the two stoppers30at the two end covers13, the repulsive force applied to the vibrator40can be increased, thereby improving a vibrating effect of the vibration motor100.

The vibrator40includes an iron core41located in the middle, a rolling friction portion43spaced apart from the iron core41, and a second magnet45located between the iron core41and the rolling friction portion43. Two rolling friction portions43and two second magnets45are provided. The two rolling friction portions43are symmetrical to each other with respect to the iron core41, and the two rolling friction portions43are respectively located at sides close the two end covers13. The two second magnets45are fixed to two ends of the iron core41, respectively.

The iron core41includes an iron core body portion411, and an iron core extending portion413extending from the iron core body portion411towards the rolling friction portion43. Two iron core extending portions413are provided, and the two iron core extending portions413respectively extends from the iron core body portion411towards the two rolling friction portions43.

The second magnet45has a hollow structure. The second magnet45includes a magnet body portion451and an accommodating space453surrounded by the magnet body portion451. Each of the two iron core extending portions413is received in the accommodating space453of a corresponding one of the two second magnets45, thereby improving a fixation and connection between the iron core41and the second magnet45.

The two rolling friction portions43are arranged corresponding to the two guide rails20, respectively. The rolling friction portion43includes a mass block431spaced apart from the guide rail20, a number of rolling members433connected between the mass block431and the guide rail20in a slidable way, and a mass block extending portion435extending from the mass block431towards the iron core41. The mass block extending portion435and the mass block431are formed into one piece. The rolling member433provided between the mass block431and the guide rail20results in formation of rolling friction between the vibrator40and the guide rail20, which reduces the friction force between the vibrator40and the guide rail20and the noise thereof when the vibrator40vibrates, thereby effectively improving a performance of the vibration motor100. Meanwhile, by providing the mass block431, a mass of the vibrator40is increased, thereby effectively improving the performance of the vibration motor100.

The mass block431is located in the sliding space21, and the mass block431includes a sliding surface4311spaced apart from the guide rail20, a recess4312formed by recessing from the sliding surface4311in a direction facing away from the guide rail, and a side surface4313connected to the sliding surface4311and perpendicular to the vibrating direction. The side surface4313faces towards the end cover13, and the recess4312extends to the side surface4313.

The rolling member433is at least partially received in the recess4312. The stopping sheet60is affixed to the side surface4313, and a projection of the recess4312in the direction perpendicular to the vibrating direction at least partially overlaps the stopping sheet60. By affixing the stopping sheet60to the side surface4313, a position of the rolling member433can be well restricted, thereby preventing the rolling member433from falling and improving stability of the vibration motor100.

A projection of the mass block431in the direction perpendicular to the vibrating direction has a rectangular shape. The sliding surface4311includes two first surfaces4314parallel to and spaced apart from each other, and two second surfaces4315that connect the two first surfaces4314and are parallel to and spaced apart from each other. The recess4312is formed by recessing from the first surface4314and/or from the second surface4315. For example, in this embodiment, the first surfaces4314and the second surfaces4315are each provided with the recess4312. That is, in this embodiment, each mass block431is provided with four recesses4312. Correspondingly, each of the rolling friction portions43is provided with four rolling members433, and the four rolling members433are received in the four recesses4312, respectively.

In this embodiment, the guide rail20has a hollow rectangular structure. The Four recesses4312correspond to four walls of the guide rail20, respectively, and the four rolling members433correspond to four walls of the guide rail20, respectively. In this way, the mass block431is completely spaced apart from the guide rail20, and the friction force can be effectively reduced through the rolling members433. It should be understood that, in other embodiments, the guide rail20may be formed in any other shape, and a number of the rolling member433may be different as needed, as long as the rolling member433is provided between the guide rail20and the mass block431to reduce the friction force and to separate the mass block431from the guide rail20.

In this embodiment, the rolling member433is a spherical ball, and the recess4312is parallel to the vibrating direction. It should be noted that, in other embodiments, the recess4312may also be perpendicular to the vibrating direction, the rolling member433may be a cylindrical rolling member, and the cylindrical rolling member includes two top surfaces spaced apart from each other and a side surface connecting the two top surfaces. The side surface abuts against the mass block431and the guide rail20, thereby forming the rolling friction.

The mass block extending portion435is received in the accommodating space453to improve the connection and fixation between the mass block431and the second magnet45.

The coil50has a hollow structure and is fixed into the main body portion11. The guide rail20and the coil50are sequentially arranged along an extending direction of the main body portion11. The coil50is located at a middle position of the main body portion11, and the two guide rails20are respectively located at two ends of the main body portion11and are arranged symmetrically to each other with respect to the coil50. For example, a winding direction of the coil50is parallel to the vibrating direction.

Two stopping sheets60are provided in one-to-one correspondence to the two mass blocks431.

With reference toFIG.4, the second magnets45located at two ends of the iron core41have opposite magnetic poles, and the second magnet45and the first magnet31have the same magnetic pole. For example, in this embodiment, a side of the first magnet31close to the second magnet45is S polarity, and a side of the second magnet45close to the first magnet31is S polarity, and the other side of the second magnet45facing away from the first magnet31is N polarity.

The magnetic induction lines of the two second magnets45are emitted outward through the iron core41and interact with the energized coil50to generate a driving force, with which the vibrator40is driven to reciprocate along an extending direction of the main body portion11. The magnetic pole of the first magnet31are opposite to the magnetic pole of the magnetic poles of the second magnet45, so as to form a repulsive force, which provides the required support stiffness of the vibrator40in the extending direction of the main body portion11. Since the first magnet31cannot provide support stiffness to the vibrator40in other directions, the vibrator40may be in contact with the guide rail20, and the rolling member433is arranged to provide the rolling friction between the vibrator40and the guide rail20, thereby effectively reducing the friction force and thus reducing the noise. In this way, the performance of the vibration motor100can be improved. The vibration motor100provided by the present invention fully utilizes the space of the vibrator40, without requiring a large space for installing the bearings. Moreover, the vibrator40has a greater mass, which also improves the performance. Meanwhile, the rolling friction portion43has a relatively simple structure, avoiding a complicated structure of the bearings.

Compared with the related art, in the vibration motor according to the present invention, the rolling friction portion and the guide rail are provided, and the rolling friction portion includes the mass block spaced apart from the guide rail and a number of rolling members connected between the mass block and the guide rail in a slidable way, thereby providing the rolling friction between the vibrator and the case through the rolling members. The friction force between the vibrator and the guide rail is relatively low, and thus the noise is low, which effectively improves performance of the vibration motor.

The above description merely illustrates some embodiments of the present invention. It should be noted that those skilled in the art may make modifications without departing from the concept of the present invention, and all these modifications shall fall into the protection scope of the present invention.