CN203879931U

CN203879931U - Magnetic bearing

Info

Publication number: CN203879931U
Application number: CN201190001181.XU
Authority: CN
Inventors: 筒井幸雄; 大户基道
Original assignee: Yaskawa Electric Corp
Current assignee: Yaskawa Electric Corp
Priority date: 2011-12-09
Filing date: 2011-12-09
Publication date: 2014-10-15
Anticipated expiration: 2021-12-09
Also published as: WO2013084362A1

Abstract

The utility model discloses a magnetic bearing (10), which is provided with electromagnets (11) and permanent magnets (12), wherein each electromagnet (11) comprises an electromagnet magnetic core (13) and a coil (14); the permanent magnets (12) support a rotating shaft part (21) together with the electromagnets in a non-contact way by utilizing magnetic attraction force; each electromagnet magnetic core is provided with a magnetic reluctance changing part (40) which is arranged in a path through which a magnetic field generated by the coil of the corresponding electromagnet passes; and the permanent magnets are arranged on parts corresponding to the magnetic reluctance changing parts of the electromagnet magnetic cores, so that magnetic fields generated by the permanent magnets do not pass through the magnetic reluctance changing parts.

Description

Magnetic bearing

Technical field

The utility model relates to magnetic bearing, particularly relates to the magnetic bearing that possesses electromagnet and permanent magnet.

Background technique

In the past, the known magnetic bearing that possesses electromagnet and permanent magnet.For example, in Japanese kokai publication hei 11-101235 communique, disclose such magnetic bearing.

In above-mentioned Japanese kokai publication hei 11-101235 communique, a kind of magnetic bearing is disclosed, this magnetic bearing possesses: electromagnet, it consists of the electromagnetic steel plate duplexer (electromagnet magnetic core) that is wound with field coil; And permanent magnet, it is installed on electromagnetic steel plate duplexer.In this magnetic bearing, be configured to, generation magnetic field in the face that electromagnet and permanent magnet all extend at axial direction along running shaft (running shaft part), utilize thus magnetic attraction on radial direction with non-contacting mode supporting rotating shaft.In addition, in this magnetic bearing, the mode equipped with permanent magnetism body that the magnetic circuit forming with the magnetic field with by producing from electromagnet intersects.

Prior art document

Patent documentation

Patent documentation 1: Japanese kokai publication hei 11-101235 communique

Model utility content

The problem that model utility will solve

; in the disclosed magnetic bearing of above-mentioned Unexamined Patent 11-101235 communique; the mode equipped with permanent magnetism body that the magnetic circuit forming due to the magnetic field with by producing from electromagnet intersects; therefore, exist the magnetic field producing from electromagnet in the opposite direction of the direction of magnetization of permanent magnet, to put on the situation of permanent magnet.Therefore, there is the such problem of irreversible demagnetization that permanent magnet easily occurs.

The utility model completes in order to solve above-mentioned such problem, and an object of the present utility model is to provide a kind of magnetic bearing of generation of the irreversible demagnetization that can suppress permanent magnet.

For the means of dealing with problems

In order to reach above-mentioned purpose, the magnetic bearing of an aspect of the present utility model possesses: electromagnet, and it comprises electromagnet magnetic core and coil; And permanent magnet, it is installed on electromagnet magnetic core, utilize magnetic attraction with cordless supporting rotating shaft part together with electromagnet, electromagnet magnetic core has magnetic resistance change rate portion, described magnetic resistance change rate portion is configured in the path of the magnetic field that produces from the coil of electromagnet passing through, permanent magnet is configured in the part corresponding with the magnetic resistance change rate portion of electromagnet magnetic core, makes the magnetic field producing from permanent magnet not by magnetic resistance change rate portion.

Model utility effect

In magnetic bearing aspect one of the present utility model, as mentioned above, at electromagnet magnetic core, magnetic resistance change rate portion is set, this magnetic resistance change rate portion is configured in the path of passing through from the magnetic field of the coil generation of electromagnet, permanent magnet is configured in to the part corresponding with the magnetic resistance change rate portion of electromagnet magnetic core, makes the magnetic field producing from permanent magnet not by magnetic resistance change rate portion.Thus, the magnetic field producing from coil is not by permanent magnet, but by magnetic resistance change rate portion formation magnetic circuit, therefore, the magnetic circuit consisting of the magnetic field producing from coil can not intersect with permanent magnet.Consequently, the magnetic field producing from coil can not put on permanent magnet in the opposite direction of the direction of magnetization of permanent magnet, therefore, can suppress the generation of the irreversible demagnetization of permanent magnet.

Accompanying drawing explanation

Fig. 1 be the 1st mode of execution of the present utility model magnetic bearing along axial schematic sectional view.

Fig. 2 is the integrally-built figure that the magnetic bearing of the 1st mode of execution of the present utility model is shown.

Fig. 3 is for the electromagnet of magnetic bearing and the mobile partial enlarged drawing in the magnetic field that permanent magnet produces from the 1st mode of execution of the present utility model is described.

Fig. 4 is the integrally-built figure that the magnetic bearing of the 2nd mode of execution of the present utility model is shown.

Fig. 5 is the partial enlarged drawing that the structure of the magnetic bearing of the 1st variation of the 1st mode of execution of the present utility model is described.

Fig. 6 is the partial enlarged drawing that the structure of the magnetic bearing of the 2nd variation of the 1st mode of execution of the present utility model is described.

Fig. 7 is the partial enlarged drawing that the structure of the magnetic bearing of the 3rd variation of the 1st mode of execution of the present utility model is described.

Fig. 8 is the partial enlarged drawing that the structure of the magnetic bearing of the 4th variation of the 1st mode of execution of the present utility model is described.

Fig. 9 is the partial enlarged drawing that the structure of the magnetic bearing of the 5th variation of the 1st mode of execution of the present utility model is described.

Figure 10 is the partial enlarged drawing that the structure of the magnetic bearing of the 6th variation of the 1st mode of execution of the present utility model is described.

Figure 11 is the partial enlarged drawing that the structure of the magnetic bearing of the 7th variation of the 1st mode of execution of the present utility model is described.

Figure 12 be the 1st mode of execution of the present utility model the 8th variation magnetic bearing along axial schematic sectional view.

Embodiment

Below, based on accompanying drawing, mode of execution of the present utility model is described.

(the 1st mode of execution)

First, with reference to Fig. 1～Fig. 3, the structure of the magnetic bearing 10 of the 1st mode of execution of the present utility model is described.

As shown in Figure 1, magnetic bearing 10 has the axial direction of the motor 20 of running shaft 21 (axially: the both sides direction that running shaft 21 extends) are provided with a pair of.This pair of magnetic bearing 10 separates respectively space (space 30 with gap length L1 (with reference to Fig. 3)) configuration of regulation at radial direction (radially: along be the direction of the straight line of radiated entends from the rotating center O (with reference to Fig. 2) of running shaft 21 in the face vertical with running shaft 21) with respect to running shaft 21.And running shaft 21 is examples of " running shaft part " of the present utility model.

In addition, as shown in Figure 2, magnetic bearing 10 possesses electromagnet 11 and permanent magnet 12.Described electromagnet 11 and permanent magnet 12 are configured to, all in face vertical with running shaft 21 and that radially (radial direction) extends, produce magnetic field (with reference to single-point line and the double dot dash line of Fig. 3), utilize thus magnetic attraction diametrically with non-contacting mode supporting rotating shaft 21.And electromagnet 11 is configured to and comprises: electromagnet magnetic core 13, by vertically, (axial direction) stacked a plurality of electromagnetic steel plates (with reference to Fig. 1) form for it; With coil 14, it is wound in the section 1 16a described later of electromagnet magnetic core 13.In addition, permanent magnet 12 consists of rare earth element magnet or ferrite lattice etc.At this, permanent magnet 12 is different from electromagnet 11, and it is without the current flowing in order to produce magnetic field.Therefore, with electromagnet 11 and permanent magnet 12 both sides, coming in the 1st mode of execution of supporting rotating shaft 21, and only with electromagnet 11, coming the situation of supporting rotating shaft 21 different, can reduce power consumption.

As shown in Figure 2, electromagnet magnetic core 13 by 4 roughly the part 15 of U word shape form, these 4 roughly the part 15 of U word shape be configured to be the outer circumferential face that all shapes surround running shaft 21, and adjacent along circumferentially (sense of rotation of running shaft 21).These 4 roughly the part 15 of U word shape be configured to clip running shaft 21 from the both sides of above-below direction and left and right directions.That is, roughly the part 15 of U word shape is provided with a pair ofly in the both sides of the above-below direction of running shaft 21, and is also provided with a pair of in the both sides of the left and right directions of running shaft 21.

At this, in the 1st mode of execution, as shown in Figure 2, form 4 of electromagnet magnetic core 13 roughly the part 15 of U word shape be respectively arranged with space 40, described space 40 has the gap length L2 (with reference to Fig. 3) of hundreds of μ m left and right.And, with these 4 roughly the corresponding partial configuration in the space separately 40 of the part 15 of U word shape have permanent magnet 12.And space 40 is examples of " magnetic resistance change rate portion " of the present utility model.

As shown in Figures 2 and 3, space 40 so that roughly the part 15 of U word shape in the separated mode that makes progress in week, be located near the circumferential central part of the part 15 of U word shape roughly.Specifically, space 40 forms, near the circumferential central part of the part 15 of U word shape roughly, along the magnetic field with producing from coil 14 (with reference to the single-point line of Fig. 3) by the vertical direction (radially) of the direction in space 40, extend.Thus, roughly the part 15 of U word shape is separated into the part 16 across the opposed a pair of roughly L word shape in space 40 completely.At this, the part 16 of a pair of roughly L word shape across the opposed end face in space 40, form parallel to each other.That is, space 40Yi Qi gap length L 2 (with reference to Fig. 3) in the running shaft 21 sides mode equal with permanent magnet 12 sides along radially extending.And roughly the part 16 of L word shape is an example of " magnetic core part " of the present utility model.

As shown in Figures 2 and 3, the part 16 of a pair of roughly L word shape is configured to across space 40 mutually opposed.In addition, the part 16 of a pair of roughly L word shape has respectively: section 1 16a, and it is along radially extending; With part 2 16b, its end from a side contrary to running shaft 21 of section 1 16a is along the circumferentially 40 sides extensions to space.And, at the section 1 16a coil 14 of reeling.In addition, on the surface of a side contrary to running shaft 21 of part 2 16b, be provided with tabular surface 16c.And, on this tabular surface 16c, dispose the tabular permanent magnet 12 with thickness t 1 (with reference to Fig. 3).

As shown in Figure 3, permanent magnet 12 is configured on these 2 tabular surface 16c in the mode of 2 tabular surface 16c of the part 16 of a pair of roughly L word shape of the part 15 of the roughly U word shape of leap formation electromagnet magnetic core 13.In addition, near the surperficial 12a of part 16 sides that are positioned at a pair of roughly L word shape of permanent magnet 12, be magnetized in a side and opposite side and there is mutually different polarity (N polarity or S polarity).In addition, being positioned at of permanent magnet 12 is magnetized near the contrary polarity surperficial 12a having with part 16 sides of a pair of roughly L of being positioned at of permanent magnet 12 word shape near the surperficial 12b with the contrary side of part 16 of a pair of roughly L word shape.

Specifically, as shown in Figure 3, near the roughly region of the surperficial 12a of part 16 sides of L word shape that is positioned at of permanent magnet 12 is magnetized to: the region in left side has S polarity, and the region on right side has N polarity.In addition, near the region being positioned at the surperficial 12b with the contrary side of part 16 of L word shape roughly of permanent magnet 12 is magnetized to: the region in left side has N polarity, and the region on right side has S polarity.And being positioned at the surperficial 12b of the contrary side of part 16 of L word shape roughly of permanent magnet 12 covered by block or tabular yoke 17.This yoke 17 forms has the tabular of the thickness t 2 (with reference to Fig. 3) less than the thickness t of permanent magnet 12 1 (with reference to Fig. 3).In addition, yoke 17 and permanent magnet 12 bond together by binder etc.

At this, in the 1st mode of execution, as shown in Figure 3, the gap length L2 in space 40 is set to less than the thickness t of permanent magnet 12 1.Thus, the magnetic field producing from coil 14 (with reference to the single-point line of Fig. 3), not by permanent magnet 12, forms magnetic circuits but pass through space 40.; in general; the permeability of the permeability of the air in formation space 40 and the permanent magnet 12 consisting of rare earth element magnet or ferrite lattice etc. about equally; therefore; if the gap length L2 in space 40 is set as less than the thickness t of permanent magnet 12 1, the magnetic resistance in space 40 becomes less than the magnetic resistance of permanent magnet 12.Thus, in the situation that flow to part 2 16b side from being wound in the magnetic field that the coil 14 of the section 1 16a of the part 16 of L word shape roughly produces from section 1 16a, this magnetic field can be to permanent magnet 12 side flow, but to space 40 side flow.

In addition, in the 1st mode of execution, as shown in Figure 3, to be set to the summation (2 * L1) of gap length L1 in 2 spaces 30 passing through than the magnetic field producing from coil 14 (with reference to the single-point line of Fig. 3) and the magnetic field (with reference to the double dot dash line of Fig. 3) producing from permanent magnet 12 large for the gap length L2 in space 40.Thus, the magnetic field producing from permanent magnet 12 is not by space 40 but forms magnetic circuit by space 30.That is, 40He space, space 30 consists of the air mutually with equal permeability, therefore, the gap length L2 in space 40 is being set as when larger than 2 times of the gap length L1 in space 30, and it is larger than the magnetic resistance of the total in 2 spaces, place 30 that the magnetic resistance in space 40 becomes.Thus, in the situation that the magnetic field producing from permanent magnet 12 is to the part 2 16b side flow of the part 16 of L word shape roughly, Bu Huixiang space, this magnetic field 40 side flow, but flow to space 30 sides via section 1 16a.

And, in the 1st mode of execution, as shown in Figure 3, the magnetic field producing from coil 14 (with reference to the single-point line of Fig. 3) is mutually roughly consistent by the region of running shaft 21 with the magnetic field (with reference to the double dot dash line of Fig. 3) producing from permanent magnet 12 by the region of running shaft 21.

In the 1st mode of execution, as mentioned above, space 40 path that the magnetic field (with reference to the single-point line of Fig. 3) being configured in from coil 14 generations of electromagnet 11 is passed through is arranged at electromagnet magnetic core 13, permanent magnet 12 is configured in to the part corresponding with the space 40 of electromagnet magnetic core 13, makes the magnetic field (with reference to the double dot dash line of Fig. 3) producing from permanent magnet 12 by space 40.Thus, the magnetic field producing from coil 14 is not by permanent magnet 12, but by space 40 formation magnetic circuits, therefore, the magnetic circuit consisting of the magnetic field producing from coil 14 can not intersect with permanent magnet 12.Consequently, the magnetic field producing from coil 14 can not put on permanent magnet 12 in the opposite direction of the direction of magnetization of permanent magnet 12, therefore, can suppress the generation of the irreversible demagnetization of permanent magnet 12.

In addition, in the 1st mode of execution, as mentioned above, to there is the mode of the magnetic resistance less than the magnetic resistance of permanent magnet 12, form space 40.Thus, can easily make the magnetic field (with reference to the single-point line of Fig. 3) producing from the coil 14 of electromagnet 11 flow to space 40 sides, rather than flow to permanent magnet 12 sides.

In addition, in the 1st mode of execution, as mentioned above, to there is the mode of the gap length L1 (with reference to Fig. 3) less than the thickness t of permanent magnet 12 1 (with reference to Fig. 3), form space 40.Thus, can easily make the magnetic resistance in space 40 be less than the magnetic resistance of permanent magnet 12.

In addition, in the 1st mode of execution, as mentioned above, to there is the mode of the gap length L2 (with reference to Fig. 3) larger than the gap length L1 (with reference to Fig. 3) in the space 30 between electromagnet magnetic core 13 and running shaft 21 2 times (2 * L1), form space 40.Thus, can make the magnetic resistance in space 40 be greater than the magnetic resistance of total in the space 30 at 2 places, therefore, can easily make the magnetic field (with reference to the double dot dash line of Fig. 3) producing from permanent magnet 12 flow to space 30 sides, rather than flow to space 40 sides.

In addition, in the 1st mode of execution, as mentioned above, the direction (radially) that the magnetic field producing along the coil 14 with from electromagnet 11 (with reference to the single-point line of Fig. 3) intersects extends ground and forms space 40, thereby the part 15 of the roughly U word shape of electromagnet magnetic core 13 is separated into completely to the part 16 of a pair of roughly L word shape.At this, in the situation that link by part across the part 16 of the opposed a pair of roughly L word shape in space 40, meeting is via the leakage field of the part generation permanent magnet 12 of its link, and therefore, the amount from permanent magnet 12 by the magnetic flux in space 30 reduces.On the other hand, in the 1st mode of execution, utilize space 40 to make the part 15 of U word shape roughly be separated into the part 16 of a pair of roughly L word shape completely, the leakage field that can suppress thus permanent magnet 12 occurs, therefore, can suppress the amount by the magnetic flux in space 30 from permanent magnet 12 reduces.

In addition, in the 1st mode of execution, as mentioned above, cross over the part 16 configuration permanent magnets 12 of a pair of roughly L word shape.Thus, the part 16 of separated a pair of roughly L word shape, via permanent magnet 12 combinations, therefore, can improve the intensity of the electromagnet magnetic core 13 of the part 16 that comprises a pair of roughly L word shape completely.

In addition, in the 1st mode of execution, as mentioned above, the side and the opposite side that near the surperficial 12a of part 16 sides of a pair of roughly L of being positioned at of permanent magnet 12 word shape, are magnetized in the part 16 of a pair of roughly L word shape are had to mutually different polarity (N polarity or S polarity), and, being positioned at of permanent magnet 12 is magnetized near the contrary polarity surperficial 12a having with part 16 sides of a pair of roughly L of being positioned at of permanent magnet 12 word shape near the surperficial 12b with the contrary side of part 16 of a pair of roughly L word shape.Thus, can easily make via being positioned at of the surperficial 12a of part 16 sides of a pair of roughly L of being positioned at of permanent magnet 12 word shape and permanent magnet 12 different at a side and the opposite side of the part 16 of a pair of roughly L word shape from the turnover direction in the magnetic field of the surperficial 12b turnover of the contrary side of part 16 of a pair of roughly L word shape.Consequently, can make the magnetic field (with reference to the double dot dash line of Fig. 3) that produces from permanent magnet 12 from a side direction opposite side of the part 16 of a pair of roughly L word shape or flow swimmingly from another lateralization.

In addition, in the 1st mode of execution, as mentioned above, be provided with yoke 17, this yoke 17 covers the surface with the contrary side of part 16 of a pair of roughly L word shape that is positioned at of permanent magnets 12.Thus, can utilize leakage magnetic field that yoke 17 suppresses to produce with the surface of the contrary side of part 16 of a pair of roughly L word shape from being arranged in of permanent magnet 12 to air.

In addition, in the 1st mode of execution, as mentioned above, the mutual roughly consistent mode in the region of the magnetic field producing with the coil 14 from electromagnet 11 (with reference to the single-point line of Fig. 3) by running shaft 21 and the magnetic field (with reference to the double dot dash line of Fig. 3) producing from permanent magnet 12 region by running shaft 21 forms magnetic bearing 10.Thus, can make the roughly consistent with the region that permanent magnet 12 produces magnetic attraction based on electromagnet 11 of running shaft 21, therefore, can easily carry out for the control of the supporting force of supporting rotating shaft 21 (magnetic attraction) non-contactly.

In addition, in the 1st mode of execution, as mentioned above, on the surface of the part corresponding with space 40 of electromagnet magnetic core 13, tabular surface 16c is set, permanent magnet 12 is configured on tabular surface 16c.Thus, can permanent magnet 12 be installed on to electromagnet magnetic core 13 with stable state by means of tabular surface 16c.

In addition, in the 1st mode of execution, as mentioned above, be configured to, the electromagnet magnetic core 13 with space 40 is configured to surround to the outer circumferential face of running shaft 21, make electromagnet 11 and permanent magnet 12 intersecting with running shaft 21 and produce magnetic field (with reference to single-point line and the double dot dash line of Fig. 3) in the face radially extending of running shaft 21, utilize thus magnetic attraction diametrically with non-contacting mode supporting rotating shaft 21.At this, in general, in magnetic bearing, in order to suppress running shaft, be out of shape because of the magnetic attraction of electromagnet and permanent magnet, preferably, shorten the axial length (the axial length in the region of the running shaft that the magnetic field producing from electromagnet and permanent magnet is passed through) of the part being supported non-contactly by electromagnet and permanent magnet of running shaft.In this case, in the 1st mode of execution, the mode that produces magnetic field with (in axial vertical face) in the face intersecting with running shaft 21 has formed electromagnet 11 and permanent magnet 12, therefore, the mode that produces magnetic field with (in axial face) in face with along running shaft 21 forms electromagnet 11 to be compared with the situation of permanent magnet 12, can shorten the axial length (the axial length in the region of the running shaft 21 passing through from the magnetic field of electromagnet 11 and permanent magnet 12 generations) of part support non-contactly by electromagnet 11 and permanent magnet 12 of running shaft 21.Thus, can suppress running shaft 21 is out of shape because of the magnetic attraction of electromagnet 11 and permanent magnet 12.

In addition, in the 1st mode of execution, as mentioned above, the part 16 with a pair of roughly L word shape of the section 1 16a radially extending is configured to across space 40 opposed, form thus the roughly part 15 of U word shape, to comprise that roughly the mode of the part 15 of U word shape forms electromagnet magnetic core 13.Thus, flowing along the part of the part 15 of the roughly U word shape of electromagnet magnetic core 13 in the magnetic field (with reference to the single-point line of Fig. 3) producing from the coil 14 of electromagnet 11, thus, can easily form by the magnetic circuit of running shaft 21.Consequently, can easily produce the supporting force (magnetic attraction) for supporting rotating shaft 21.

In addition, in the 1st mode of execution, as mentioned above, the mode that clips running shaft 21 with the both sides from radially arranges the part 15 of a pair of roughly U word shape.Thus, the magnetic attraction of the part 15 of a pair of roughly U word shape only works in the direction that clips running shaft 21, therefore, can easily carry out clipping the control of magnetic attraction of the direction of running shaft 21.

(the 2nd mode of execution)

Next, with reference to Fig. 4, the magnetic bearing 110 of the 2nd mode of execution of the present utility model is described.In the 2nd mode of execution, different by 4 above-mentioned the 1st mode of executions that roughly part 15 of U word shape forms from electromagnet magnetic core 13, electromagnet magnetic core 113 is described by 4 examples that roughly part 115 of T word shape forms.

In the 2nd mode of execution, as shown in Figure 4, electromagnet magnetic core 113 configured by the mode of surrounding the outer circumferential face of running shaft 21 to be all shapes 4 the roughly part 115 of T word shape forms.These 4 roughly the part 115 of T word shape be configured to across space 40a along circumferentially adjacent.And, all the time, conventionally adopt by make such electromagnet magnetic core (the electromagnet magnetic core without space) that roughly a plurality of electromagnet magnetic cores of T word shape form along being circumferentially combined into one that has between the part of a plurality of roughly T word shapes along circumferentially adjacent.

At this, 4 roughly the part 115 of T word shape have respectively: section 1 115a, it radially extends; With part 2 115b, extend to circumferential both sides its end from a side contrary to running shaft 21 of section 1 115a.And, at section 1 115a, be wound with coil 14.In addition, on the surface of a side contrary to running shaft 21 of part 2 115b, be provided with tabular surface 115c.And permanent magnet 12 is configured to across 2 tabular surface 115c upper, these 2 tabular surface 115c are located at adjacent 2 part 2 115b of the part 115 of T word shape roughly.In addition, at permanent magnet 12, be bonded with yoke 17 with the surperficial 12b of the contrary side of part 115 of T word shape roughly.

Thus, in the 2nd mode of execution, permanent magnet 12 is not passed through in the magnetic field producing from coil 14 (with reference to the single-point line of Fig. 4), but forms magnetic circuit by the section 1 115a along circumferentially adjacent and part 2 115b, space 30a (space between part 2 115b and running shaft 21), space 40 and running shaft 21.In addition, the magnetic field (with reference to the double dot dash line of Fig. 4) producing from permanent magnet 12, not by space 40a, forms magnetic circuit but pass through the circumferential adjacent section 1 115a in edge and part 2 115b, space 30a and running shaft 21.

In the 2nd mode of execution, same with above-mentioned the 1st mode of execution, the gap length L2a that is arranged at the space 40a of electromagnet magnetic core 113 is set as less than the thickness t of permanent magnet 12 1 (with reference to Fig. 4), and larger than the summation (2 * L1a) of the gap length L1a (with reference to Fig. 4) of 2 space 30a between electromagnet magnetic core 113 and running shaft 21.

In the 2nd mode of execution, as mentioned above, electromagnet magnetic core 113 is configured to and comprises the roughly part 115 of T word shape, this roughly the part 115 of T word shape there is section 1 115a and part 2 115b, this section 1 115a radially extends, and this part 2 115b extends to circumferential both sides from the end of a side contrary to running shaft 21 of the section 1 115a that radially extends.And, to be provided with 4 roughly parts 115 of T word shape across space 40 along circumferential adjacent mode.Thus, only, by normally used electromagnet magnetic core all the time (by make to have the electromagnet magnetic core (the electromagnet magnetic core without space) that roughly a plurality of electromagnet magnetic cores of T word shape form along being circumferentially combined into one between the part of a plurality of roughly T word shapes along circumferentially adjacent), space 40 being set, just can easily form the electromagnet magnetic core 113 that can utilize space 40 to suppress the irreversible demagnetization generation of permanent magnets 12.

And this disclosed mode of execution is example in all respects, should not be considered limiting content.Scope of the present utility model is illustrated by claims, rather than is illustrated by the explanation of above-mentioned mode of execution, in addition, and the meaning that the scope with claim that is also included in is equal to and all changes in scope.

For example, in the above-mentioned the 1st and the 2nd mode of execution, show and use the space being formed by air as the such example of magnetic resistance change rate portion of the present utility model, but the utility model is not limited to this.In the utility model, also can use mold pressing resin as magnetic resistance change rate portion.That is, can in the space of above-mentioned the 1st and the 2nd mode of execution, fill the mold pressing resin with the magnetic resistance less than the magnetic resistance of permanent magnet.In this case, if make the length of magnetic path of mold pressing resin less and larger than the gap length in the space between electromagnet magnetic core and running shaft than the thickness of permanent magnet, can easily make the magnetic resistance of mold pressing resin be less than the magnetic resistance of permanent magnet.

In addition, in the above-mentioned the 1st and the 2nd mode of execution, show such example: on the surface of the side contrary to running shaft of the part corresponding with space of electromagnet magnetic core, be provided with tabular surface (radial end face), equipped with permanent magnetism body on this tabular surface, but the utility model is not limited to this.In the utility model, also can on the axial end vertical with radial end face of the part corresponding with space of electromagnet magnetic core, configure permanent magnet.

In addition, in above-mentioned the 1st mode of execution, as shown in Figure 3, show the gap length L2 in space 40 at the running shaft 21 sides example equal with permanent magnet 12 sides, but the utility model is not limited to this.In the utility model, can the 1st variation as shown in Figure 5 make like this gap length in space 41 different with permanent magnet 12 sides in running shaft 21 sides.And space 41 is examples of " magnetic resistance change rate portion " of the present utility model.

As shown in Figure 5, in the 1st variation, space 41 gradually becomes large mode from running shaft 21 sides towards permanent magnet 12 sides with its gap length and forms.That is, forming across the opposed end face in space 41 of the part 216 of a pair of roughly L word shape, separated gradually mutually towards permanent magnet 12 sides from running shaft 21 sides.At this, in the 1st variation, the mean gap length L 3 in space 41 (mean value of the gap length L5 of the end of the gap length L4 of the end of running shaft 21 sides and permanent magnet 12 sides) is set as less than the thickness t of permanent magnet 12 1 and larger than the summation (2 * L1) of the gap length L1 in 2 spaces 30 between electromagnet magnetic core 213 and running shaft 21.And roughly the part 216 of L word shape is an example of " magnetic core part " of the present utility model.

In the 1st variation, as mentioned above, the gap length L5 of the end of permanent magnet 12 sides in space 41 is greater than the gap length L4 of the end of running shaft 21 sides, therefore, can further suppress the magnetic field that produces from permanent magnet 12 not by space 30 part of permanent magnet 12 sides by space 41 leak.

In addition, in above-mentioned the 1st mode of execution, as shown in Figures 2 and 3, show and be provided with the example that makes electromagnet magnetic core 13 complete separated spaces 40, but the utility model is not limited to this.In the utility model, also can arrange and not make electromagnet magnetic core completely separated but make its separated in fact space.For example, as Fig. 6, Fig. 7 and Fig. 8 the 2nd, the 3rd and the 4th variation shown in respectively, space 42a, the 42b and the 42c that form following such state also can be set: state electromagnet magnetic core 313a, 313b and 313c being linked up by thinner part 18a, 18b and 18c.And space 42a～42c is an example of " magnetic resistance change rate portion " of the present utility model.

As shown in Figure 6, in the 2nd variation, across the opposed end face of the part 316a of the opposed a pair of roughly L word shape of space 42a, in the end of permanent magnet 12 sides, by thinner part 18a, interlink.In addition, as shown in Figure 7, in the 3rd variation, across the opposed end face of the part 316b of the opposed a pair of roughly L word shape of space 42b, in the end of running shaft 21 sides, by thinner part 18b, interlink.In addition, as shown in Figure 8, in the 4th variation, across the opposed end face of the part 316c of the opposed a pair of roughly L word shape of space 42c, in the end of permanent magnet 12 sides and these both sides of end of running shaft 21 sides, by thinner part 18c, interlink.At this, in the 2nd, the 3rd and the 4th variation, in order to suppress to occur via thinner part 18a, 18b and 18c the leakage field of permanent magnet 12, preferably make thickness t 3 (with reference to Fig. 6), t4 (with reference to Fig. 7) and the t5 (with reference to Fig. 8) of thinner part 18a, 18b and 18c be thinned to the manufacturing limit of steel plate.And roughly the part 316a～316c of L word shape is an example of " magnetic core part " of the present utility model.

In the 2nd～4th variation, as mentioned above, the space 42a～42c that forms following such state is set: state electromagnet magnetic core 313a～313c being linked up by thinner part 18a～18c.Thus, part 316a～the 316c that forms a pair of roughly L word shape of electromagnet magnetic core 313a～313c becomes the all-in-one-piece state that interlinks by thinner part 18a～18c, therefore, electromagnet magnetic core 313a～313c can be manufactured as the parts of the one that is easy to manufacture by the processing of steel plate, and can cut down number of components.

In addition, in above-mentioned the 1st mode of execution, as shown in Figure 3, show such example: near near this two side surperficial 12a of part 16 sides of a pair of roughly L word shape of permanent magnet 12 and the surperficial 12b of permanent magnet 12 and the contrary side of part 16 a pair of roughly L word shape is magnetized into and has N polarity or S polarity, but the utility model is not limited to this.In the utility model, also the 5th variation that can be as shown in Figure 9 like this, only has mutually different polarity (N polarity and S polarity) by the side and the opposite side that are magnetized near the surperficial 112a of part 16 sides of a pair of roughly L of being positioned at of permanent magnet 112 word shape in the part 16 of a pair of roughly L word shape.

As shown in Figure 9, in the 5th variation, permanent magnet 112 is configured to leap on the tabular surface 16c of part 16 settings of a pair of roughly L word shape.Near the surperficial 112a of part 16 sides that are arranged in a pair of roughly L word shape of this permanent magnet 112, in the region in the left side of Fig. 9, be magnetized to and there is S polarity, and be geomagnetic into and there is N polarity in the region on the right side of Fig. 9.

In the 5th variation, as mentioned above, only to magnetizing near the surperficial 112a of part 16 sides of a pair of roughly L of being positioned at of permanent magnet 112 word shape.Thus, from near the surperficial 12a of part 16 sides of a pair of roughly L of being positioned at of permanent magnet 12 word shape and permanent magnet 12 to be positioned near above-mentioned the 1st mode of execution (with reference to Fig. 3) that this two side is magnetized the surperficial 12b with the contrary side of part 16 of a pair of roughly L word shape different, due to the parts (parts corresponding with the yoke 17 of above-mentioned the 1st mode of execution) that are set to the path in the magnetic field that produces from permanent magnet 112 with the surperficial 112b of the contrary side of part 16 of a pair of roughly L word shape that are positioned at without at permanent magnet 112, therefore can cut down number of components.

In addition, in above-mentioned the 1st mode of execution, as shown in Figures 2 and 3, show the example that the part 16 of yoke 17 and a pair of roughly L word shape is set to different parts, but the utility model is not limited to this.In the utility model, the 6th variation that can be as shown in figure 10 like this, arranges all-in-one-piece parts by the part 416 of yoke 417 and a pair of roughly L word shape.

As shown in figure 10, in the 6th variation, the part 416 of a pair of roughly L word shape of the two end part of the left and right directions of the yoke 417 of electromagnet magnetic core 413 and electromagnet magnetic core 413 links mutually by the linking department 19 of thin wall shape.This linking department 19 is configured to cover the both ends of the surface of the left and right directions of permanent magnet 12.At this, in the 6th variation, in order to prevent from occurring via linking department 19 leakage field of permanent magnets 12, preferably make the thickness t 6 (Figure 10 with reference to) of linking department 19 be thinned to the manufacturing limit of steel plate.And roughly the part 416 of L word shape is an example of " magnetic core part " of the present utility model.

In the 6th variation, as mentioned above, utilize the linking department 19 of thin wall shape that the part 416 of the yoke of electromagnet magnetic core 413 417 and a pair of roughly L word shape is interlinked.Thus, the part 416 of yoke 417 and a pair of roughly L word shape can be manufactured as the parts that are easy to the one of the manufacturing by steel plate, and can be cut down number of components.

In addition, in above-mentioned the 1st mode of execution, as shown in Figures 2 and 3, the mode that shows to cross over the part 16 of a pair of roughly L word shape arranges the example of 1 permanent magnet 12, but the utility model is not limited to this.In the utility model, the 7th variation that can be as shown in figure 11 like this, arranges 2 permanent magnet 212a and 212b in corresponding with the part 16 of a pair of roughly L word shape respectively mode.

As shown in figure 11, in the 6th variation, permanent magnet 212a configuration is on the tabular surface 16c of part 16 of roughly L word shape of left side configuration of Figure 11.This permanent magnet 212a is magnetized to the roughly near surface of part 16 sides of L word shape and has S polarity, and the near surface that is magnetized to yoke 17 sides has N polarity.In addition, in the 6th variation, permanent magnet 212b configuration is on the tabular surface 16c of part 16 of roughly L word shape of right side configuration of Figure 11.This permanent magnet 212b is magnetized to the roughly near surface of part 16 sides of L word shape and has N polarity, and the near surface that is magnetized to yoke 17 sides has S polarity.

In addition, in above-mentioned the 1st mode of execution, as shown in Figure 1, show the utility model is applied to diametrically to the example with the magnetic bearing 10 of non-contacting mode supporting rotating shaft 21, but, like this, the utility model also can be applied in the axial direction the magnetic bearing 510 of supporting rotating shaft 21 non-contactly to the 8th variation as shown in figure 12.

As shown in figure 12, in the 8th variation, be provided with a pair of magnetic bearing 510 that comprises electromagnet 511 and permanent magnet 512 in the both sides radially of running shaft 21, this electromagnet 511 comprises electromagnet magnetic core 513 and coil 514.This pair of magnetic bearing 510 is arranged to respectively, clips the plate-shaped member 22 intersecting with running shaft 21 from axial both sides.In the 8th variation, be configured to, electromagnet 511 and permanent magnet 512 all produce magnetic field (with reference to single-point line and the double dot dash line of Figure 12) in the face along running shaft 21, utilize thus magnetic attraction supporting rotating shaft 21 non-contactly in the axial direction.And plate-shaped member 22 is examples of " running shaft part " of the present utility model.

At this, in the 8th variation, at the electromagnet magnetic core 513 of electromagnet 111, be provided with the space 40b that the magnetic field (with reference to the single-point line of Figure 12) that produces for the coil 514 from electromagnet 511 is passed through.And, at partial configuration corresponding to space 40b with electromagnet magnetic core 513, there is permanent magnet 512, make the magnetic field (with reference to the double dot dash line of Figure 12) producing from permanent magnet 512 not by space 40b.In addition, on the surface of the side contrary to electromagnet magnetic core 513 of permanent magnet 512, be provided with yoke 517.And space 40b is an example of " magnetic resistance change rate portion " of the present utility model.

In the 8th variation, also same with above-mentioned the 1st mode of execution, the gap length L2b that is arranged at the space 40b of electromagnet magnetic core 513 is set as less than the thickness t of permanent magnet 512 7 (with reference to Figure 12), and larger than the summation (2 * L1b) of the gap length L1b (with reference to Figure 12) of 2 space 30b between electromagnet magnetic core 513 and running shaft 21.

Claims

1. a magnetic bearing, is characterized in that,

Described magnetic bearing possesses:

Electromagnet (11,511), it comprises electromagnet magnetic core (13,113,213,313a, 313b, 313c, 413,513) and coil (14,514); With

Permanent magnet (12,112,212a, 212b), it is installed on described electromagnet magnetic core, utilizes magnetic attraction with non-contacting mode supporting rotating shaft part (21,22) together with described electromagnet,

Described electromagnet magnetic core has magnetic resistance change rate portion (40,40a, 40b, 41,42a, 42b, 42c), and described magnetic resistance change rate portion is configured in the path of the magnetic field that produces from the coil of described electromagnet passing through,

Described permanent magnet is configured in the part corresponding with the described magnetic resistance change rate portion of described electromagnet magnetic core, makes the magnetic field that produces from described permanent magnet not by described magnetic resistance change rate portion.

2. magnetic bearing according to claim 1, is characterized in that,

Described magnetic resistance change rate portion has the magnetic resistance less than the magnetic resistance of described permanent magnet.

3. magnetic bearing according to claim 1, is characterized in that,

Described magnetic resistance change rate portion has the length of magnetic path less than the thickness of described permanent magnet.

4. magnetic bearing according to claim 1, is characterized in that,

Described magnetic resistance change rate portion has the large length of magnetic path of gap length of part space between dividing than described electromagnet magnetic core and described rotary shaft, that pass through for the magnetic field producing from described coil and described permanent magnet (30,30a, 30b).

5. magnetic bearing according to claim 1, is characterized in that,

The direction that described magnetic resistance change rate portion intersects along the magnetic field with producing from described coil extends and forms, and makes described electromagnet magnetic core be separated into a pair of magnetic core partly (16,216,316a, 316b, 316c, 416).

6. magnetic bearing according to claim 5, is characterized in that,

Described permanent magnet configures to cross over the mode of described a pair of magnetic core part.

7. magnetic bearing according to claim 6, is characterized in that,

Described magnetic resistance change rate portion is the space (40,41,43) that makes described electromagnet magnetic core completely separated, or forms the space (42a, 42b, 42c) that utilizes the state that thin part links up described electromagnet magnetic core.

8. magnetic bearing according to claim 6, is characterized in that,

The near surface of at least described a pair of magnetic core part side of described permanent magnet is magnetized to, and at a described a pair of magnetic core side and opposite side partly, has mutually different polarity.

9. magnetic bearing according to claim 8, is characterized in that,

Near the surface (12a) of the described a pair of magnetic core part side of described permanent magnet, be magnetized to, at a described a pair of magnetic core side and opposite side partly, there is mutually different polarity,

Near described permanent magnet and surface (12b) the contrary side of described a pair of magnetic core part, be magnetized to, there is the polarity contrary with the near surface of the described a pair of magnetic core part side of described permanent magnet.

10. magnetic bearing according to claim 9, is characterized in that,

Described magnetic bearing also possesses yoke (17,417,517), and this yoke (17,417,517) covers described permanent magnet and the surface contrary side of described a pair of magnetic core part.

11. magnetic bearings according to claim 10, is characterized in that,

Described yoke and described a pair of magnetic core part link mutually by the linking department (19) of thin wall shape.

12. magnetic bearings according to claim 5, is characterized in that,

Described permanent magnet with described a pair of magnetic core part respectively corresponding mode be provided with a pair of.

13. magnetic bearings according to claim 1, is characterized in that,

Described magnetic bearing is configured to, and passes through the region of described running shaft part and pass through described running shaft region partly from the magnetic field of described permanent magnet generation consistent with each other from the magnetic field of described coil generation.

14. magnetic bearings according to claim 1, is characterized in that,

The surface of the part corresponding with described magnetic resistance change rate portion of described electromagnet magnetic core comprises tabular surface (16c, 115c),

On the described tabular surface of the part corresponding with described magnetic resistance change rate portion that described permanent magnet is configured in described electromagnet magnetic core.

15. magnetic bearings according to claim 1, is characterized in that,

The described electromagnet magnetic core with described magnetic resistance change rate portion is configured to, and surrounds the outer circumferential face of described running shaft part,

Described electromagnet and described permanent magnet are configured to, by producing magnetic field in the face partly intersecting with described running shaft and extending along described running shaft radial direction partly, thereby utilize magnetic attraction in non-contacting mode, to support described running shaft part on radial direction.

16. magnetic bearings according to claim 15, is characterized in that,

Described electromagnet magnetic core comprises the part (15) of U word shape, and the part of described U word shape (15) is across described magnetic resistance change rate portion, along circumferentially adjacent, to form by the part (16,216,316a, 316b, 316c, 416) with the pair of L word shape of the part (16a) of extending along radial direction is configured to.

17. magnetic bearings according to claim 16, is characterized in that,

The mode that the part of described U word shape clips described running shaft part with the both sides from radial direction is at least provided with a pair of.

18. magnetic bearings according to claim 15, is characterized in that,

Described electromagnet magnetic core comprises the part (115) of T word shape, and the part of described T word shape (115) has: the part (115a) of extending along radial direction; With the part (115b) of dividing the end of a contrary side to extend to circumferential both sides with described rotary shaft from described part of extending along radial direction,

The part of described T word shape is to be provided with a plurality of across the described magnetic resistance change rate portion circumferential adjacent mode in edge.

19. magnetic bearings according to claim 18, is characterized in that,

The part of described T word shape is to be provided with 4 across the described magnetic resistance change rate portion circumferential adjacent mode in edge.

20. magnetic bearings according to claim 1, is characterized in that,

Described rotary shaft divides the plate-shaped member that comprises running shaft (21) and intersect with described running shaft (22),

The described electromagnet magnetic core with described magnetic resistance change rate portion is configured to, and from the both sides of the axial direction of described running shaft, clips described plate-shaped member,

Described electromagnet and described permanent magnet are configured to, and utilize magnetic attraction in non-contacting mode, to support described plate-shaped member on the axial direction of described running shaft, thereby in non-contacting mode, support described running shaft part on the axial direction of described running shaft.