Linear motor actuator

Abstract

The present invention provides a linear motor actuator provided with a movable yoke facing a stator, the linear motor actuator being characterized by being provided with: magnets directly disposed on both surfaces of the yoke in the thickness direction; a width direction roller guide mechanism that supports both ends of the yoke in the width direction; and a thickness-direction roller guide mechanism that supports both ends of the yoke in the thickness direction, the width-direction roller guide mechanism supporting at least one side of the yoke in the width direction at a position fixed in the width direction, and supporting the other side of the yoke in the width direction at a position variable in the width direction.

Description

Technical Field

[0001] The present invention relates to a linear motor actuator for linearly vibrating a test component in a direction of extension and contraction in various tests of a vehicle or a vehicle component. Background Art

[0002] In the past, there was a need for durability evaluation and performance evaluation in various tests of various vehicles and vehicle parts. In such durability evaluation and performance evaluation tests, the test parts are linearly excited using an exciter, for example, a linear motor actuator is driven as an exciter. In addition, a temperature rise caused by heat may occur inside the linear motor actuator, and the yoke with a movable part may expand in the width direction. In contrast, Patent Document 1 describes a linear motor having a structure that absorbs the thermal expansion of the yoke caused by heat.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2003-324888 Summary of the invention

[0006] Problems to be solved by the invention

[0007] However, in Patent Document 1, the thickness and space of the movable part required to mount the sliding guide on the side surface increase the mass of the movable part, thereby reducing the output acceleration and responsiveness of the linear motor actuator. On the other hand, if the thickness of the movable part is reduced for weight reduction, the size of the mounted sliding guide becomes smaller, and the durability of the guide mechanism is reduced due to micro-movement during micro-excitation, etc., and the generation of vibration increases, and the noise of the guide movement increases.

[0008] Therefore, an object of the present invention is to provide a linear motor actuator that reduces the weight of a movable element to improve output acceleration and responsiveness, and at the same time increases the durability and life of a guide mechanism.

[0009] Solutions to Solve Problems

[0010] In order to achieve the above-mentioned purpose, the present invention provides a linear motor actuator having a yoke that is opposite to a stator and can move, characterized in that it comprises: magnets that are directly arranged on both sides of the yoke in the thickness direction; a width-direction roller guide mechanism that supports both ends of the yoke in the width direction; and a thickness-direction roller guide mechanism that supports both ends of the yoke in the thickness direction, the width-direction roller guide mechanism supports at least one side of the yoke in the width direction as a fixed position in the width direction, and supports the other side of the yoke in the width direction as a variable position in the width direction.

[0011] Effects of the Invention

[0012] According to the above configuration, the output acceleration and responsiveness of the linear motor actuator can be improved, and the durability of the guide mechanism can be prolonged. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic partially cutaway cross-sectional view of a linear motor actuator according to an embodiment of the present invention.

[0014] Figure 2 (a) is Figure 1 The enlarged view of the IIa frame, Figure 2 (b) is Figure 2 Enlarged view of box IIb in (a).

[0015] Figure 3 yes Figure 1 Schematic cross-sectional view of line III-III.

[0016] Figure 4 (a) is the yoke before it expands in the width direction due to thermal expansion. Figure 3 A partial cross-sectional view of Figure 4 (b) is the yoke after it expands in the width direction due to thermal expansion. Figure 3 In addition, the block 33 and the block 39 are arranged at positions where they do not contact each other.

[0017] Figure 5 It is a schematic cross-sectional view of a linear motor actuator according to another embodiment of the present invention.

[0018] Figure 6 yes Figure 5 A magnified view of the VI box.

[0019] Figure 7 This is a schematic cross-sectional view of a conventional linear motor actuator. DETAILED DESCRIPTION

[0020] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the embodiment.

[0021] (Structural example of a linear motor actuator)

[0022] Figure 1 It is a schematic cut-away cross-sectional view of a linear motor actuator according to an embodiment of the present invention. Figure 2 (a) is Figure 1 The enlarged view of the IIa frame, Figure 2 (b) is Figure 2 Enlarged view of box IIb in (a). Figure 3 yes Figure 1 The linear motor actuator 1 comprises: a pair of frames 10; a leg portion 12 (see Figure 3 ), which are respectively arranged on the two end parts of a pair of frames 10 in a manner of forming a U-shaped cross-sectional shape; a stator 11, which is arranged on the inner surface of the pair of frames 10 in a manner opposite to each other; a movable part 20, which has a yoke 21 that is opposite to the stator 11 and can move; width-direction roller guide mechanisms 31a, 31b, which fix the position of at least one side of the width direction of the yoke 21 in the width direction and make the position of the other side of the width direction of the yoke 21 variable; and a thickness-direction roller guide mechanism 37, which is arranged on the inner surface of the pair of frames 10 and supports the two ends of the yoke 21 in the thickness direction.

[0023] (stator)

[0024] The stator 11 includes a coil to generate a magnetic field, and is arranged in the length direction and fixed to the frame 10 by a plurality of bolts. The stator 11 is arranged in a manner that the stator 11 on one side is opposed to the stator 11 on the other side, and the movable member 20 moves between the stators 11. In the present embodiment, when the stator 11 is fixed, it is fixed by bolts, but the frame 10 and the stator 11 can be fixed as long as they can be fixed, and can also be fixed by a heat-resistant adhesive or the like. By passing a driving current from a power supply unit (not shown) through the coil, a moving magnetic field that moves linearly is generated, so that the movable member 20 moves linearly relative to the stator 11.

[0025] (Movable Parts)

[0026] The movable member 20 includes a yoke 21, a magnet 22, and baffles 23 disposed at both ends in the width direction and both ends in the thickness direction of the yoke 21. Figure 2 As shown in (b), the magnets 22 are alternately arranged in a manner in which the magnetic poles are different in the length direction of the yoke 21, and are arranged in a manner in which the magnetic poles are reversed on both sides in the thickness direction of the yoke 21. In this embodiment, the magnetic pole of the magnet 22a on the stator 11 side is the N pole, and the magnetic pole on the yoke 21 side is the S pole, and the magnetic pole of the magnet 22b on the stator 11 side is the S pole, and the magnetic pole on the yoke 21 side is the N pole. In addition, the baffle 23 is installed as a member with high hardness as a baffle of the roller 38 of the thickness direction roller guide mechanism 37 described later, and the contact portion between the baffle 23 and the roller 38 can withstand long-term repeated contact. The baffle 23 is the size of the range in which only the roller 38 contacts, and the mass of the movable part 20 is suppressed to a minimum. In this embodiment, the baffle 23 is arranged on the yoke 21, but it is not limited to this, and only the yoke 21 may be arranged. In this case, the yoke 21 itself needs to have a hardness that can withstand the contact of the roller 38, so the yoke can also be made of carbon steel with a ferromagnetic body.

[0027] Thus, in the movable part 20 of this embodiment, the magnet 22 can be arranged without considering the magnetic pole saturation caused by the magnet 22, and the thickness of the yoke 21 can be minimized. In addition, the weight of the movable part 20 can be reduced, and the output acceleration and responsiveness of the exciting action can be improved.

[0028] (Characteristics of the cross-sectional shape of the linear motor actuator)

[0029] In the present invention, the thickness direction roller guide mechanism 37 has two or three rollers 38 and a block 39 for supporting the rollers 38, and a plurality of rollers 38 are arranged in the length direction. In addition, the thickness direction roller guide mechanism 37 is fixed to the frame 10 by bolts, and is located on the inner surface of the frame 10, respectively, in the thickness direction of the movable member 20, that is, Figure 3 In the up-down direction on the paper, the block 39 of the movable part 20 abuts against the baffle 23. The thickness direction roller guide mechanism 37 abuts against the movable part 20, and the position in the thickness direction can be supported, and the movable part 20 is supported by the roller 38 so as to be movable. Thus, the position of the movable part 20 can be supported even during vibration in various tests of vehicles and vehicle parts. The roller 38 is not included in the mass of the movable part 20, so that a size with a large load capacity can be used without increasing the mass of the movable part, and the life of the guide mechanism can be extended. In addition, the block 39 of the thickness direction roller guide mechanism 37 is arranged at a position where it does not contact the blocks 33 of the width direction roller guide mechanisms 31a and 31b described later.

[0030] The width direction roller guide mechanisms 31a and 31b are provided between the leg portion 12 of one frame 10 and the leg portion 12 of the other frame 10 so as to face the width direction of the movable member 20. Figure 3 As shown, one width direction roller guide mechanism 31a includes: a roller 32 that supports the movable member 20; a block 33 that supports the roller 32; and a block 34 that fixes the block 33 to the inner surface by bolts 33a and to the side of the leg 12 of the frame 10 by bolts 34a. The roller 32 of the width direction roller guide mechanism 31a supports the side end of the movable member 20 and fixes the position in the width direction. Similar to the thickness direction roller guide mechanism 37, the roller 32 is not included in the mass of the movable member 20, so that a size with a large load capacity can be used without increasing the mass of the movable part, and the life of the guide mechanism can be extended.

[0031] The width direction roller guide mechanism 31b on the other side has: a roller 32 that supports the movable member 20; a block 33 that supports the roller 32; a block 35 that fixes the block 33 to the inner surface by a bolt 33a, and can be variably fixed to the side of the leg 12 of the frame 10 by a bolt 35a via a spring 35b as an elastic body; and a roller guide support body 36 that supports the yoke 21 of the block 35 in the thickness direction and the length direction, and is fixed to the side of the leg 12 of the frame 10 by a bolt 36a. As described in detail later, the roller 32 of the width direction roller guide mechanism 31b supports the side end of the movable member 20 and can variably support the position in the width direction. In this embodiment, a spring 35b as an elastic member is provided between the block 35 and the bolt 35a to cope with the thermal expansion of the yoke 21. Thus, even if the yoke 21 expands in the width direction of the yoke 21 due to heat, force acts from the roller 32 of the width direction roller guide mechanism 31 b in the direction of the block 35 , and the force generated by the expansion can be dealt with.

[0032] Figure 4 (a) is the linear motor actuator 1 before the yoke 21 is expanded Figure 3 Schematic cross-sectional view of . In this embodiment, the movable member 20 is excited by moving in the length direction. At this time, the roller 32 of the width direction roller guide mechanism 31b supports the position of the movable member 20 in the width direction, and the roller 38 of the pair of thickness direction roller guide mechanisms 37 supports the position of the movable member 20 in the thickness direction. Thus, the movable member 20 can be moved in the length direction by using the width direction roller guide mechanism 31b and the pair of thickness direction roller guide mechanisms 37.

[0033] On the other hand, when the yoke 21 expands in the width direction due to thermal expansion of the movable member 20, as shown in FIG. Figure 4 As shown in (b), a pair of thickness direction roller guide mechanisms 37 are used to support the thickness direction, and at the same time, the spring 35b is urged toward the outside in the width direction to absorb the thermal expansion of the block 33 and the block 35 via the roller 32 of the width direction roller guide mechanism 31b.

[0034] In addition, since a structure is adopted in which the baffle 23 in the width direction of the movable part 20 contacts the roller 32 of the width direction roller guide mechanism 31b and the baffle 23 in the thickness direction of the movable part 20 and a pair of rollers 38 of the thickness direction roller guide mechanism 37 are used for support, the position of the movable part 20 can be supported.

[0035] The block 35 provided on the outer side surface of the leg portion 12 of the frame 10 has the function of supporting the roller 32 via the block 33, but in order to further enhance the rigidity of the block 35, the block 35 is supported in the length direction and the thickness direction by a roller guide support body 36. The roller guide support body 36 supports the position of the block 35 to be variable. In the present embodiment, the roller guide support body 36 is in contact with the entire contact surface of the block 35, but as long as the block 35 can be supported, a part of the block 35 may be in contact with the roller guide support body 36.

[0036] Thus, by means of a structure such as the width direction roller guide mechanism 31b, even if the yoke 21 is thermally expanded in the width direction, the spring of the width direction roller guide mechanism 31b can be used to press the side surface of the yoke 21 in the width direction with an appropriate pressure, and the position of the movable member 20 in the width direction can be supported without separation to follow the expansion and contraction of the yoke 21, and the movable member 20 can be moved. Furthermore, by relieving the displacement caused by thermal expansion with the elastic member, it is possible to prevent a large load from being applied to the roller of the roller guide mechanism, and to achieve a longer service life.

[0037] In addition, by supporting the side end of the movable part 20 and moving it through the rollers 32 of the width-direction roller guide mechanisms 31a and 31b, it is possible to reduce the movement sound that may be generated by the sliding guide of Patent Document 1, and to reduce the impact on the sound evaluation of the test component during the test of the test component.

[0038] In the present embodiment, the elastic member is a spring, but the present invention is not limited thereto. For example, an elastic body such as elastomer may be interposed between the bolt 35 a and the block 35 .

[0039] (Characteristics of the load suppression roller guide mechanism of the linear motor actuator)

[0040] Figure 5 It is a schematic cross-sectional view of a linear motor actuator according to another embodiment of the present invention, which is a linear motor actuator including a lateral load guide mechanism. Figure 6 yes Figure 5Enlarged view in frame VI of . During various tests of vehicles and vehicle components, there are cases where a lateral load is applied in a direction orthogonal to the telescopic direction as a test condition of the test component, and cases where a load is generated in an orthogonal direction as a characteristic of the test component. The linear motor actuator 1 of the present invention is then subjected to a force in a lateral direction perpendicular to the longitudinal direction (hereinafter also referred to as a lateral load), and therefore is provided with a load suppression guide mechanism 40 (hereinafter also referred to as a lateral load suppression guide mechanism) that suppresses the lateral load in a manner that can be loaded and unloaded. The lateral load suppression guide mechanism 40 is fixed to the linear motor actuator 1 in a manner that can be loaded and unloaded by bolts not shown. In addition, in the present embodiment, the lateral load suppression guide mechanism 40 is loadable and removable, but may also be formed integrally with the linear motor actuator 1.

[0041] The lateral load suppression guide mechanism 40 includes a table 41 , a pair of guide shafts 42 disposed at both ends of the table 41 , and a lateral load roller guide 43 fixed to the test device frame 2 .

[0042] The table 41 is connected to the front end of the movable element 20 of the linear motor actuator 1 and moves in the longitudinal direction together with a pair of guide shafts 42. The table 41 is connected to the test component at the surface opposite to the surface connected to the front end of the movable element 20 to transmit the excitation action to the test component.

[0043] The lateral load roller guide 43 includes two pairs of rollers 44 that sandwich the guide shaft 42 in the lateral direction perpendicular to the longitudinal direction and in the longitudinal direction perpendicular to the longitudinal direction and the lateral direction. The lateral load roller guide 43 includes two pairs of rollers 44 at both ends in the longitudinal direction.

[0044] like Figure 6 As shown in the figure, when a lateral load F1 is applied, the lateral loads F2 and F3 are respectively transmitted to the roller 44 of the lateral load suppression guide mechanism 40 through the guide shaft 42 of the lateral load suppression guide mechanism 40 having rigidity. In addition, the lateral load roller guide 43 of the lateral load suppression guide mechanism 40 absorbs the reaction force F4 of the fixed test device frame 2. The roller 44 of the lateral load suppression guide mechanism 40 can rotate even if it is subjected to the lateral loads F2 and F3, so that the movement of the test component is not affected by the exciting action.

[0045] In this way, the lateral load roller guide 43 of the lateral load suppression guide mechanism 40 absorbs F4, and the yoke 21 of the movable part 20 of the linear motor actuator 1 is not affected by the lateral load, so that the strength for dealing with the lateral load is not required, and the thinnest can be achieved. In addition, even under the condition of inputting the lateral load, the movable part 20 can be used in the form of a lightweight linear motor actuator 1.

[0046] (Comparison example with conventional linear motor actuator)

[0047] Figure 7 The conventional linear motor actuator 100 includes a movable element 104 having a plurality of magnet plates on a commercially available yoke 102 and magnets 103 disposed thereon on the side surface of a structure 101 , and a stator 105 having a coil facing the movable element 104 .

[0048] The conventional linear motor actuator 100 has a structure 101 for mounting a magnet plate. However, the conventional linear motor actuator has a problem that the mass of the movable element 104 increases, and the output acceleration, responsiveness, etc. decrease.

[0049] However, in the present invention, as a solution to the above-mentioned problem, Figure 1 As shown in FIG. 1 , magnets 22 are alternately arranged in a manner that the magnetic poles are different in the length direction relative to the yoke 21 of the movable part 20, and are arranged on both sides of the yoke 21 in the thickness direction in a manner that the magnetic poles are reversed, thereby making it possible to minimize the thickness of the yoke 21 in the thickness direction without considering magnetic pole saturation. As a result, a structure is not required as in conventional linear motor actuators, and the movable part can be made lighter.

[0050] Explanation of symbols

[0051] 1—linear motor actuator; 11—stator; 21—yoke; 22—magnet; 31a, 31b—width direction roller guide mechanism; 37—thickness direction roller guide mechanism.

Claims

1. A linear motor actuator comprising a yoke which is opposed to a stator and is movable, The linear motor actuator is characterized by comprising: Magnets are directly disposed on both sides of the yoke in the thickness direction; a width-direction roller guide mechanism that supports both ends of the yoke in the width direction; and a thickness direction roller guide mechanism that supports both ends of the yoke in the thickness direction, The width direction roller guide mechanism supports at least one side of the yoke in the width direction so as to fix the position in the width direction, and supports the other side of the yoke in the width direction so as to change the position in the width direction.

2. The linear motor actuator according to claim 1, characterized in that The magnets are arranged on both surfaces in the thickness direction of the yoke so that the magnetic poles are reversed.

3. The linear motor actuator according to claim 2, characterized in that The width direction roller guide mechanism has one roller guide fixed to the main body of the linear motor actuator and the other roller guide pressed by an elastic body so as to be variable.

4. The linear motor actuator according to claim 3, characterized in that: The thickness direction roller guide mechanism includes two pairs of roller guides that respectively support both ends of the yoke in the width direction.

5. The linear motor actuator according to any one of claims 1 to 4, characterized in that: A load suppression roller guide mechanism for suppressing a load generated by movement of the yoke is further provided in a detachable manner.

6. The linear motor actuator according to claim 5, characterized in that The load suppression roller guide mechanism includes: a block that fixes the yoke; at least one guide shaft that is fixed to the block; and at least two pairs of roller guides that support the at least one guide shaft.

7. A linear motor actuator comprising a yoke which is opposed to a stator and is movable, The linear motor actuator is characterized by comprising: Magnets are directly disposed on both sides of the yoke in the thickness direction; A width direction roller guide mechanism, which supports both ends of the yoke in the width direction; a thickness-direction roller guide mechanism that supports both ends of the yoke in the thickness direction; and a load suppression roller guide mechanism that suppresses a load generated by movement of the yoke, The width direction roller guide mechanism supports at least one side of the yoke in the width direction so as to fix the position in the width direction, and supports the other side of the yoke in the width direction so as to change the position in the width direction.

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