JP4023099B2 - Eddy current reducer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an eddy current reduction device, and more particularly to an eddy current reduction device using an electromagnet.
[0002]
[Prior art]
An eddy current reduction device using an electromagnet includes, as main components, a braking drum coupled to a rotating shaft, a plurality of drums arranged at equal intervals in the circumferential direction facing the inner peripheral surface of the braking drum, and an iron core And a magnet support member (ring) which is disposed inside the brake drum and holds each electromagnet structure (Japanese Patent Application No. 2000-289219, Japanese Patent Application No. 2000-289219). 2000-286037).
[0003]
An eddy current reduction device using an electromagnet can switch between a non-braking state and a braking state only by controlling a current applied to an electromagnetic coil. For this reason, it is not necessary to move a magnet using an actuator etc. like the eddy current reduction device using a permanent magnet, and it has the feature that a state change is easy.
[0004]
When the polarities of the adjacent magnetic pole parts of the adjacent electromagnet structures are different, that is, when the adjacent magnetic pole parts of the adjacent electromagnet structure are the S pole and the N pole, do not form a magnetic circuit between the adjacent magnetic pole parts. Therefore, it is necessary to form the magnet support member from a non-magnetic material such as Al or an Al alloy or austenitic stainless steel.
[0005]
[Problems to be solved by the invention]
By the way, when an eddy current reduction device is mounted on an automobile or the like, there is a problem that strength may be insufficient in a magnet support member made of Al or Al alloy because it may receive strong vibration and impact. That is, in the eddy current reduction device using this magnet support member, there is a slight difficulty in reliability against vibration and shock.
[0006]
Further, the magnet support member made of austenitic stainless steel has a problem that the moldability is not so good and the manufacturing cost is high.
[0007]
An object of the present invention created in view of the above circumstances is to provide an inexpensive eddy current reduction device that is highly reliable with respect to vibration and shock.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, an eddy current reduction device according to the present invention is provided with a plurality of circumferentially equidistantly facing the inner peripheral surface of a braking drum coupled to a rotating shaft, and an iron core and a pair of magnetic poles. An electromagnet structure integrally including a portion, an electromagnetic coil wound around the iron core of the electromagnet structure, and a ring-shaped magnet support member disposed inside the brake drum and fixed to a non-rotating portion The eddy current reduction device provided, wherein the pair of magnetic pole portions of the plurality of electromagnet structural members are arranged to face the inner peripheral surface of the braking drum, and the magnet support member formed of steel or cast iron If, by clamping their magnets structure axially with another magnet support member, the steel or of the contact portion of the magnet support member formed of cast iron and each electromagnet structure fits Ri next to as least An interposition member made of non-magnetic material is installed at the part that contacts the magnetic pole. Those were.
[0009]
According to the above configuration, the magnet support member has high strength, good formability, high reliability with respect to vibration and impact, and an inexpensive eddy current reduction device can be obtained.
[0010]
Moreover, you may form the magnet support member which clamps the said electromagnet structure in an axial direction with steel or cast iron, respectively .
[0011]
Also, disposed adjacent the electromagnet structure different polarities so that each electromagnet arrangement of magnetic pole portions adjacent, of the contact portion between the magnet support member and the electromagnet structure made of the steel or cast iron, at least It is preferable to provide an intervening member made of a non-magnetic material at a portion in contact with the adjacent magnetic pole portion.
[0012]
In addition, each electromagnet structure is disposed so that the polarities of adjacent magnetic pole sections of the adjacent electromagnet structures are the same, and the contact between the magnet support member made of steel or cast iron and each electromagnet structure , the portion in contact with the magnetic pole portion adjacent at least above, it is preferable to provide a non-magnetic material or Ranaru intervening member.
[0013]
Moreover, it is preferable to form the radial inner peripheral side of the magnetic pole part of the electromagnet structure in a tapered shape.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a preferred embodiment of the invention will be described with reference to the accompanying drawings.
[0015]
FIG. 1 shows a partial cross-sectional view of the eddy current reduction device according to the first embodiment, and FIG.
[0016]
As shown in FIG. 1 and FIG. 2, the eddy current reduction device 10 according to the present embodiment includes a braking drum 12 coupled to a rotating shaft 11 and an equal circumferential interval facing the inner peripheral surface of the braking drum 12. 2 (only three are shown in FIG. 2), and an electromagnet structure 20 that is integrally provided with an iron core portion 21 and magnetic pole portions 22a and 22b, and a brake drum 12, and each electromagnet. Magnet support members 23a and 23b for holding the structure 20 are provided. Here, each electromagnet structure 20 is disposed so that the polarities of the adjacent magnetic pole portions 22a and 22b of the adjacent electromagnet structures 20a to 20c,... Are different, and at least one (left side in FIG. 1). The magnet support member 23a is formed of steel or cast iron. Further, the electromagnetic coil 32 is wound around the iron core portion 21 via the winding frame 31 to form the electromagnet 30.
[0017]
Also, as shown in FIG. 2, at least a portion of the magnet support member 23a made of steel or cast iron where the adjacent magnetic pole portions 22a and 22b are in contact with each other (enclosed portion z by a broken line in FIG. 2) is made of a nonmagnetic material. Intervening member 24 is interposed. As the interposed member 24, for example, a member made of an aggregate of discontinuous interposed pieces 24a, 24b,... In the circumferential direction, or a portion that is continuous in the circumferential direction and corresponds to the electromagnet 30 as shown in FIG. It may consist of an annular body 34 having an opening 34a.
[0018]
The clamping by the magnet support members 23a and 23b uses fastening means, for example, bolts 28 and nuts 29, and, as shown in FIG. 1, the electromagnet components 20 and the interposition members 24 are fastened together by the magnet support members 23a and 23b. Is. Here, as shown in FIG. 4, the magnet support member 23a and the interposition member 24 are fixed using bolts 48 and nuts 49, and the bolts 28 and nuts 29 are used to form each electromagnet structure by the interposition members 24 and magnet support members 23b. The body 20 may be fastened together.
[0019]
Each electromagnet structure 20 is formed by laminating a plurality of electromagnetic steel plates 25 (20 in FIG. 1) as shown in FIG. 1, forging a soft magnetic block material, or soft magnetic Various things, such as what formed combining the bar material, are mentioned, It does not specifically limit.
[0020]
A radially inner end (lower end in FIG. 1) of the magnet support member 23a is fixed to a non-rotating portion of the automobile, for example, a rear cover of a transmission, a differential cage of a rear axle, or the like. Further, the position of the radially outer end (the upper end in FIG. 1) of the magnet support member 23a may be located outside the brake drum 12.
[0021]
Next, the operation of the present invention will be described.
[0022]
Since the magnet support member 23a made of steel or cast iron has higher strength than the magnet support member made of Al or Al alloy, when the eddy current reduction device 10 using the magnet support member 23a is mounted on an automobile or the like, There is no risk of damage due to insufficient strength even when subjected to strong vibration or impact.
[0023]
In addition, the magnet support member 23a made of steel or cast iron has better formability and lower manufacturing costs than the magnet support member made of austenitic stainless steel. As a result, the magnet support member 23a The manufacturing cost of the eddy current reduction device 10 used can be reduced.
[0024]
Furthermore, in the eddy current reduction device 10 of the present embodiment shown in FIG. 1, the magnet support member made of steel or cast iron is only the magnet support member 23a, but as shown in FIG. Among them, the left and right magnet support members 23a and 23b may be formed of steel or cast iron. In this case, interposed members 24 and 24 are provided between the magnet support members 23 a and 23 b and the electromagnet structure 20. This further improves the reliability of the eddy current reduction device 10 against vibration and impact.
[0025]
Next, another embodiment of the present invention will be described with reference to the accompanying drawings.
[0026]
FIG. 6 shows a partial cross-sectional view of an eddy current reduction device according to the second embodiment, and FIG. 7 shows a view in the direction of arrow B in FIG. In addition, the same code | symbol is attached | subjected to the member similar to FIG.1 and FIG.2.
[0027]
As shown in FIGS. 6 and 7, the eddy current reduction device 60 according to the present embodiment includes a braking drum 12 coupled to the rotating shaft 11 and an equal interval in the circumferential direction facing the inner peripheral surface of the braking drum 12. A plurality of (only three are shown in FIG. 7) are disposed, and the electromagnet structure 20 integrally including the iron core portion 21 and the magnetic pole portions 22a and 22b, and the brake drum 12 are disposed. Magnet support members 23a and 23b for holding the structure 20 are provided. Here, each electromagnet structure 20 is disposed so that the polarities of adjacent magnetic pole portions 22a and 22b of the adjacent electromagnet structures 20a to 20c,... Are the same, and at least one (left side in FIG. 6). ) Is formed of steel or cast iron. Further, the electromagnetic coil 32 is wound around the iron core portion 21 via the winding frame 31 to form the electromagnet 30.
[0028]
Further, as shown in FIG. 7, at least a portion of the magnet support member 23a where the adjacent magnetic pole portions 22a and 22b are in contact (enclosed portion z by a broken line in FIG. 7) is made of a nonmagnetic material or a ferromagnetic material. A member 74 is provided. As the interposed member 74, for example, a member made of an aggregate of discontinuous interposed pieces 74a, 74b,... In the circumferential direction, or an annular body that is continuous in the circumferential direction and has an opening at a portion corresponding to the electromagnet 30. (See FIG. 3).
[0029]
In the present embodiment, adjacent magnetic pole portions 22a, 22b of adjacent electromagnet structural bodies 20a-20c,... Have the same polarity, that is, adjacent magnetic pole portions 22a, 22b of adjacent electromagnet structural bodies 20a-20c,. Since there are S poles or N poles, no magnetic circuit is formed between the adjacent magnetic pole portions 22a and 22b. For this reason, it is not necessary to magnetically block (insulate) adjacent magnetic pole portions 22a and 22b, and an interposition member 74 made of a ferromagnetic material can be used instead of the interposition member 74 made of a nonmagnetic material. At this time, if the magnet support member 23a is made of ferromagnetic steel or cast iron, the interposition member 74 itself made of a ferromagnetic material is not required, and the eddy current reduction device 80 shown in FIG. 8 is thereby obtained.
[0030]
Further, in the eddy current reduction device 80 shown in FIG. 8, instead of using the bolts 28 and nuts 29 and fastening the electromagnet components 20 together with the magnet support members 23a and 23b, as shown in FIG. The member 23a and the interposition member 74 made of a ferromagnetic material are fixed using a bolt 98 and a nut 99, and the electromagnet components 20 are fastened together by the interposition member 74 and the magnet support member 23b using the bolt 28 and the nut 29. It may be. At this time, the magnet support member 23a is not necessarily made of steel or cast iron, and may be a conventional magnet support member, that is, a magnet support member made of Al, Al alloy, or austenitic stainless steel. As a result, the existing / existing eddy current reduction device can be replaced with the eddy current reduction device according to the present embodiment.
[0031]
Furthermore, in the eddy current reduction devices 60 and 80 shown in FIGS. 6 and 8, the magnet support member made of steel or cast iron is only the magnet support member 23a, but as shown in FIG. Among them, the left and right magnet support members 23a and 23b may be formed of steel or cast iron.
[0032]
FIG. 11 shows a partial cross-sectional view of the electromagnet structure of the eddy current reduction device according to the third embodiment. The same members as those in FIGS. 2 and 7 are denoted by the same reference numerals.
[0033]
The electromagnet structure 20 of the eddy current reduction devices 10 and 60 according to the first and second embodiments described above uses only the electromagnet 30. On the other hand, as shown in FIG. 11, the electromagnet structure 110 of the eddy current reduction device according to the present embodiment includes an electromagnet 30 in which an electromagnetic coil 32 is wound around a core portion 21 via a winding frame 31. A permanent magnet 113 provided inside the iron core 21 is used.
[0034]
More specifically, the electromagnet structure 110 forms a hollow portion 111 inside the core portion 21 of the integrally formed iron core portion 21 and magnetic pole portions 22a and 22b, and one end inside the hollow portion 111 (FIG. 11). The permanent magnet 113 is inserted and fitted to the left end (in the left), and the magnetic body 114 is inserted and fitted to the other end (the right end in FIG. 11). Here, a cylindrical body 112 made of a nonmagnetic material such as synthetic resin may be appropriately disposed between the hollow portion 111 and the permanent magnet 113 and the magnetic body 114.
[0035]
The permanent magnet 113 is magnetized so that both ends in the circumferential direction of the electromagnet structure 110 form magnetic poles (the left end in FIG. 11 is the N pole), and when the electromagnetic coil 32 is not energized, the permanent magnet 113 The magnetic field from the N pole forms a magnetic circuit that passes through the magnetic pole part 22a → the iron core part 21 → the magnetic pole part 22b → the magnetic body 114, and does not exert a magnetic field on the braking drum. Further, when the electromagnetic coil 32 is energized, that is, during braking, the left end of the iron core portion 21 is the same N pole as the permanent magnet 113 and the right end is the S pole, and a magnetic circuit is formed between the brake drum and the brake drum.
[0036]
Also in the eddy current reduction device of the present embodiment, the same effects as those of the eddy current reduction devices 10 and 60 of the first and second embodiments described above can be obtained. In addition, since the eddy current reduction device according to the present embodiment uses both the electromagnet 30 and the permanent magnet 113, compared with the eddy current reduction devices 10 and 60 according to the first and second embodiments. There is a new effect that a large braking torque can be applied to the braking drum.
[0037]
FIG. 12 shows a partial cross-sectional view of the electromagnet structure of the eddy current reduction device according to the fourth embodiment. The same members as those in FIGS. 2 and 7 are denoted by the same reference numerals.
[0038]
As shown in FIG. 11, the electromagnet configuration body 120 of the eddy current reduction device according to the present embodiment has the same configuration as the electromagnet configuration body 20 of the eddy current reduction devices 10 and 60 according to the first and second embodiments. The radially inner circumferential side (lower side in FIG. 11) of the magnetic pole portions 22a and 22b is formed in a tapered shape.
[0039]
According to the eddy current reduction device of the present embodiment, the weight of the electromagnet structure 120 is reduced as compared with the electromagnet structure 20 of the eddy current reduction devices 10 and 60 according to the first and second embodiments. Therefore, it is possible to reduce the weight of the eddy current reduction device itself, and thus contribute to improving the fuel consumption of the automobile. Needless to say, the eddy current reduction device of the present embodiment can provide the same effects as those of the eddy current reduction devices 10 and 60 of the first and second embodiments described above.
[0040]
As mentioned above, it cannot be overemphasized that embodiment of this invention is not limited to embodiment mentioned above, and various things are assumed in addition.
[0041]
【The invention's effect】
In short, according to the present invention, at least one of the magnet support members is made of steel or cast iron, so that it is possible to obtain an inexpensive eddy current reduction device that is highly reliable with respect to vibration and impact. Demonstrate.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional view of an eddy current reduction device according to a first embodiment.
FIG. 2 is a view taken in the direction of arrow A in FIG.
FIG. 3 is a plan view showing a modified example of the interposition member in FIG. 2;
FIG. 4 is a partial cross-sectional view showing a first modification of the magnet support member and the interposition member in the first embodiment.
FIG. 5 is a partial cross-sectional view showing a second modification of the magnet support member and the interposition member in the first embodiment.
FIG. 6 is a partial cross-sectional view of an eddy current reduction device according to a second embodiment.
7 is a view in the direction of arrow B in FIG.
FIG. 8 is a partial cross-sectional view showing a first modification of the magnet support member and the interposition member in the second embodiment.
FIG. 9 is a partial cross-sectional view showing a second modification of the magnet support member and the interposition member in the second embodiment.
FIG. 10 is a partial cross-sectional view showing a third modification of the magnet support member and the interposition member in the second embodiment.
FIG. 11 is a partial cross-sectional view of an electromagnet structure of an eddy current reduction device according to a third embodiment.
FIG. 12 is a partial cross-sectional view of an electromagnet configuration body of an eddy current reduction device according to a fourth embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Eddy current reduction device 11 Rotating shaft 12 Braking drum 20, 20a, 20b, 20c Electromagnet structure 21 Iron core part 22a, 22b Magnetic pole part 23a, 23b Magnet support member 24, 74 Interposition member 24a, 24b Interposition piece (interposition member)
34 Ring body (intervening member)
110, 120 Electromagnet structure 111 Hollow part 113 Permanent magnet

Claims (5)

A plurality of electromagnet structures that are arranged at equal intervals in the circumferential direction so as to face the inner peripheral surface of the braking drum coupled to the rotating shaft, and an iron core of the electromagnet structure. An eddy current reduction device comprising: an electromagnetic coil wound around a portion; and a ring-shaped magnet support member disposed inside a brake drum and fixed to a non-rotating portion, wherein the plurality of electromagnet components The pair of magnetic pole portions are arranged to face the inner peripheral surface of the brake drum, and the electromagnet structure is pivoted by the magnet support member formed of steel or cast iron and another magnet support member. and clamped in the direction, of the contact portion between the magnet support member and the electromagnet structure formed in the steel or cast iron, provided the interposed member made of a non-magnetic material portion in contact with the least neighboring Ri suit pole section also An eddy current reduction device characterized by that.   2. The eddy current reduction device according to claim 1, wherein the magnet support members for holding the electromagnet structural body in the axial direction are each formed of steel or cast iron.   Each electromagnet structure is disposed so that the polarities of adjacent magnetic pole sections of the adjacent electromagnet structures are different, and at least the adjacent portion of the contact portion between the magnet support member made of steel or cast iron and each electromagnet structure. The eddy current reduction device according to claim 1 or 2, wherein an interposition member made of a non-magnetic material is provided at a portion in contact with the matching magnetic pole portion. Each electromagnet structure is disposed so that the polarities of the adjacent magnetic pole sections of the adjacent electromagnet structures are the same, and at least the contact portion between the magnet support member made of steel or cast iron and each electromagnet structure, a portion in contact with the magnetic pole portion adjacent said eddy current reduction apparatus according to claim 1 or 2 wherein is provided a non-magnetic material or Ranaru intervening member.   The eddy current reduction device according to any one of claims 1 to 4, wherein a radially inner peripheral side of the magnetic pole portion of the electromagnet structure is formed in a tapered shape.

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