CN104779763A - Two-freedom-degree voice coil driving device - Google Patents

Abstract

The invention discloses a two-freedom-degree voice coil driving device. The two-freedom-degree voice coil driving device comprises a square-frame-shaped magnet upper cover assembly and a magnet lower cover assembly which are matched in a manner of covering up and down, wherein a permanent magnet is arranged on each side of each of the magnet upper cover assembly and the magnet lower cover assembly; a semi-closed cavity is formed between two adjacent permanent magnets at the upper part and the lower part on each of the magnet upper cover assembly and the magnet lower cover assembly; a coil assembly is arranged between the adjacent permanent magnets at the upper part and the lower part. By virtue of the two-freedom-degree voice coil driving device, a magnetic field is reinforced, the magnetic field with magnetic leakage of an electromotor is effectively shielded, and the motion of rotors in two-freedom-degree direction of the voice coil driving device is implemented.

Description

A two-degree-of-freedom voice coil drive device

technical field

The invention relates to the field of ultra-precise motion positioning equipment, in particular to a two-degree-of-freedom voice coil driving device.

Background technique

Voice coil motor (Voice Coil Actuator VCA) is a special form of direct drive motor, which has the characteristics of simple structure, small size, high speed, high acceleration and fast response. Its working principle is that the energized coil (conductor) is placed in the magnetic field A force will be generated inside, and the magnitude of the force is proportional to the current applied to the coil. The movement form of the voice coil motor manufactured based on this principle can be a straight line or a circular arc.

Since its inception, voice coil motors have been widely used in computer storage devices, aerospace instruments (such as aerospace refrigerators), precision ranging instruments (such as Hall displacement measuring devices), precision lathes and mobile phones, especially in high-end household appliances and computers. The voice coil motor is a linear motor with very advanced performance and has a wide range of application prospects.

In recent years, with the improvement of performance requirements for high-speed and high-precision positioning systems and the rapid development of voice coil motor technology, voice coil motor drives have also been widely used in many different forms of high acceleration and high frequency excitation. For example, the positioning of lenses in optical systems, the multi-coordinate positioning platform of mechanical tools, the control of precision electronic tubes and vacuum tubes in medical devices, and the drive of laser beam scanners. In flexible robots, in order to make the end effector fast and precise positioning, the voice coil motor drive can also be used to effectively suppress vibration.

In the design of the voice coil motor drive device with traditional structure, there are the following technical problems:

(1) The external magnetic flux leakage of the motor, and the mechanical structure size design of the magnetic circuit components are not suitable for the precise positioning platform with strict requirements;

(2) Due to the limitation of the structural volume, the traditional voice coil motor drive device can only achieve single-degree-of-freedom reciprocating motion, which leads to the voice coil motor drive device not meeting the requirements of small size, large output, high stroke, high frequency, and multi-degree-of-freedom motion. application requirements;

(3) Due to the unreasonable design of the magnetic circuit, the coil area of the coil mover in the magnetic circuit is not fully utilized, resulting in that the performance of the magnet cannot be fully utilized.

Contents of the invention

The technical problem to be solved by the present invention is to provide a two-way motor that can effectively shield the leakage magnetic field of the motor while strengthening the magnetic field, and the mechanical structure size design of the magnetic circuit element is suitable for the strict requirements of the precision positioning platform. Freedom Voice Coil Driver.

In order to solve the problems of the technologies described above, the present invention adopts the following technical solutions:

A two-degree-of-freedom voice coil driving device, comprising a square frame-shaped magnet upper cover assembly and a magnet lower cover assembly that are fitted up and down, and each side of the magnet upper cover assembly and the magnet lower cover assembly is provided with a For the permanent magnet, a semi-sealed chamber is formed at the position of two upper and lower adjacent permanent magnets on the magnet upper cover assembly and the magnet lower cover assembly, and a coil assembly is arranged between the upper and lower adjacent permanent magnets.

As a further improvement of the present invention: the magnet upper cover assembly and the magnet lower cover assembly both include a yoke cover and a permanent magnet installation part located on the yoke cover, the permanent magnet is embedded in the permanent magnet installation part, and the magnet The upper cover assembly and the permanent magnet mounting part on the magnet lower cover assembly cooperate to form a semi-sealed chamber.

As a further improvement of the present invention: the upper and lower permanent magnets in each semi-sealed chamber are bidirectionally magnetized in a horizontal direction, and the magnetization directions are opposite to form a closed-loop magnetic circuit perpendicular to the coil assembly.

As a further improvement of the present invention: the coil assembly includes a bobbin and coils wound on the bobbin, and the bobbins protrude from the semi-sealed chamber and are connected to each other.

As a further improvement of the present invention: the coil includes an enameled wire winding, and the coil frame includes a printed circuit board made of epoxy glass cloth laminated board FR-4.

As a further improvement of the present invention: the permanent magnet is made of NdFeB N50M material.

Compared with the prior art, the present invention has the advantages of:

(1) A two-degree-of-freedom voice coil driving device of the present invention adopts a soft iron yoke in the form of an upper and lower cover to form a semi-sealed cavity, and in the semi-sealed cavity, permanent magnets with opposite magnetic poles are used to form a closed-loop magnet. While strengthening the magnetic field, it effectively shields the magnetic field leakage of the motor, reduces the external magnetic flux leakage of the motor, and reduces the impact on the electromagnetic components that are closely arranged near the motor; at the same time, it effectively reduces the mechanical structure size of the magnetic circuit components, suitable for It is applied to the design of precision positioning platform with strict requirements on mechanical structure size.

(2) A two-degree-of-freedom voice coil driving device of the present invention can not only meet the movement requirements of the voice coil motor mover in the X-axis direction, but also the motor mover can move along the Y-axis direction, which increases the working space of the motor. The problem that the mover can only move in one direction in the existing voice coil motor structure is solved.

(3) A two-degree-of-freedom voice coil driving device of the present invention utilizes the effective coil area of the coil mover in the magnetic circuit to a greater extent, and can form a very uniform magnetic field, so that the output force of the motor can be reduced during the movement. The change is very small, especially suitable for the field of ultra-precise positioning.

Description of drawings

FIG. 1 is a schematic diagram of the three-dimensional structure of a two-degree-of-freedom voice coil driving device according to the present invention.

Fig. 2 is a three-dimensional exploded principle schematic diagram of a two-degree-of-freedom voice coil driving device of the present invention.

Fig. 3 is a schematic sectional view of A-A of Fig. 2 in an embodiment of the present invention.

Fig. 4 is a schematic diagram of the principle of the B-B section of Fig. 1 in an embodiment of the present invention.

illustration:

1. Magnet upper cover assembly; 11. Upper yoke cover; 12. Upper permanent magnet; 2. Magnet lower cover assembly; 21. Lower yoke cover; 22. Lower permanent magnet; 3. Coil assembly; 31. Coil Skeleton; 32, coil.

Detailed ways

The present invention will be described in further detail below in conjunction with specific embodiments and accompanying drawings.

As shown in Figures 1 to 4, the present invention provides a two-degree-of-freedom voice coil drive device, which includes a square frame-shaped magnet upper cover assembly 1 and a magnet lower cover assembly 2 that form an upper and lower cover fit, and the magnet upper cover A permanent magnet is arranged on each side of the assembly 1 and the magnet lower cover assembly 2, and a semi-sealed chamber is formed at the positions of two upper and lower adjacent permanent magnets on the magnet upper cover assembly 1 and the magnet lower cover assembly 2 , a coil assembly 3 is arranged between the upper and lower adjacent permanent magnets.

In this embodiment, the magnet upper cover assembly 1 and the magnet lower cover assembly 2 both include a yoke cover and a permanent magnet installation part located on the yoke cover, and the permanent magnet is embedded in the permanent magnet installation part. The permanent magnet installation parts on the magnet upper cover assembly 1 and the magnet lower cover assembly 2 cooperate to form a semi-sealed chamber.

In this embodiment, the upper and lower permanent magnets in each semi-sealed chamber are bidirectionally magnetized in a horizontal direction, and the magnetization directions are opposite to form a closed-loop magnetic circuit perpendicular to the coil assembly 3 .

As shown in Figure 4, in this embodiment, the left side of the upper permanent magnet 12 on the magnet upper cover assembly 1 is the S pole, the right side is the N pole, and the left side of the lower permanent magnet 22 on the magnet lower cover assembly 2 N pole and S pole on the right side, the S pole and N pole of the upper and lower permanent magnets face each other, so that the magnetic circuit on the left side of the permanent magnet is from bottom to top, and the magnetic circuit on the right side of the permanent magnet is from top to bottom; Since the magnet upper cover assembly 1 and the magnet lower cover assembly 2 form an upper and lower cover fit, the upper yoke cover body 11 of the magnet upper cover assembly 1 and the lower yoke cover body 21 of the magnet lower cover assembly 2 are on the outer sides of the four sides up and down. Correspondingly connected to form four semi-sealed chambers, a closed-loop magnetic field is formed through the magnetic conduction of the upper yoke cover 11 and the lower yoke cover 21, thereby effectively shielding the magnetic field leakage of the motor while strengthening the magnetic field, and reducing the external load of the motor. Flux leakage reduces the impact on the compactly arranged electromagnetic components adjacent to the motor; and the closed magnetic field passes through the effective surface of the coil assembly 3 vertically, and the current direction is perpendicular to the direction of the magnetic field, maximizing the effective area of each coil assembly 3, In this way, a greater thrust can be output and the space size of the motor can be reduced; at the same time, since the closed-loop magnetic circuit is formed by using permanent magnets with opposite magnetic poles in the semi-sealed cavity, the mechanical structure size of the magnetic circuit components is effectively reduced, and the motor capacity is reduced. The external magnetic flux leakage makes the present invention suitable for the design of precision positioning platforms with strict requirements on mechanical structure size.

As shown in Figures 1 and 2, when the two coil assemblies 3 in the X-axis direction are energized, the two coil assemblies 3 in the X-axis direction can move in the X-axis direction under the action of the Lorent magnetic force; when the Y-axis When the two coil assemblies 3 in the Y direction are energized, the two coil assemblies 3 in the Y-axis direction can realize the movement in the Y-axis direction under the action of the Loren magnetic force; when the four coil assemblies 3 are all energized, the coil assemblies 3 can realize X-axis Y-axis plane movement. This can not only meet the movement requirements of the voice coil motor mover in the X-axis direction, but also the motor mover can move along the Y-axis direction, which increases the working space of the motor and solves the problem that the mover can only be single-handed in the existing structure of the voice coil motor drive device. problem of movement.

In this embodiment, the coil assembly 3 includes a bobbin 31 and a coil 32 wound on the bobbin 31 , and the bobbins 31 protrude from the semi-sealed chamber and are connected to each other.

In this embodiment, the coil 32 includes an enameled wire winding, and the coil frame 31 includes a printed circuit board made of epoxy glass cloth laminated board FR-4.

In this embodiment, the permanent magnet is made of NdFeB N50M material. In actual use, the lateral and longitudinal dimensions of the magnet upper cover assembly 1 and the magnet lower cover assembly 2 can be slightly larger than the size of the coil assembly 3 as required, so that the coil assembly 3 can obtain a larger stroke in the X-axis and Y-axis directions.

The above are only preferred implementations of the present invention, and the protection scope of the present invention is not limited to the above-mentioned embodiments, and all technical solutions under the idea of the present invention belong to the protection scope of the present invention. It should be pointed out that for those skilled in the art, some improvements and modifications without departing from the principle of the present invention should be regarded as the protection scope of the present invention.

Claims (6)

1. a two-freedom voice coil type drive unit, it is characterized in that, comprise square frame shape magnet cover assembly (1) and magnet lower cover component (2) that formation covers cooperation up and down, every bar limit of described magnet cover assembly (1) and magnet lower cover component (2) is provided with a permanent magnet, the position on the magnet cap assemblies (1) and magnet lower cover component (2) being positioned at two neighbouring permanent magnets forms semitight chamber, is provided with a coil block (3) between neighbouring permanent magnet.

2. a kind of two-freedom voice coil type drive unit according to claim 1, it is characterized in that, described magnet cover assembly (1) and magnet lower cover component (2) include yoke lid and are positioned at the permanent magnet installation portion on yoke lid, permanent magnet is embedded at permanent magnet installation portion, and the permanent magnet installation portion in described magnet cover assembly (1) and magnet lower cover component (2) coordinates and forms semitight chamber.

3. a kind of two-freedom voice coil type drive unit according to claim 2, it is characterized in that, two the equal horizontal directions of permanent magnet up and down in described each semitight chamber are two-way magnetize and magnetizing direction on the contrary to form the magnetic loop perpendicular to coil block (3).

4. a kind of two-freedom voice coil type drive unit according to claims 1 to 3 any one, it is characterized in that, described coil block (3) comprises coil rack (31) and is wound on the coil (32) on coil rack (31), and described coil rack (31) all stretches out and is interconnected in semitight chamber.

5. a kind of two-freedom voice coil type drive unit according to claim 4, it is characterized in that, described coil (32) comprises enamelled wire winding, and described coil rack (31) comprises the printed circuit board be made up of epoxy glass cloth laminated board FR-4.

6. a kind of two-freedom voice coil type drive unit according to claim 5, it is characterized in that, described permanent magnet is made up of neodymium iron boron N50M material.