JP2022052069A - Rotary electric machine - Google Patents

Abstract

To prevent rattling in a diametrical direction of a stator of a sensor storage portion, and to improve durability and detection accuracy.SOLUTION: A sensor unit 40 is equipped with a first fixing portion that is fixed to a body portion of a stator 20, and a second fixing portion that is provided in a sensor storage portion 47 storing a sensor substrate SB, and is fixed to an attaching stay. A projecting portion 21d is disposed between a first abutting portion 47a and a second abutting portion 47b, and an insulator 22 is interposed between a projecting portion 21d of teeth 21b and the first abutting portion 47a of the sensor storage portion 47. Rattling in a diametrical direction of the stator 20 of the sensor storage portion 47 is prevented, and the damage and the like of respective sensors Su, Sv, Sw, and Sr is suppressed. Even if the sensor storage portion 47 rattles with respect to the stator 20, since the insulator 22 is interposed between the projecting portion 21d and the first abutting portion 47a, wear at a contact part with the stator 20 of the sensor storage portion 47 is suppressed.SELECTED DRAWING: Figure 6

Description

The present invention relates to a rotary electric machine including a stator, a rotor that rotates with respect to the stator, and a sensor unit that detects a rotational state of the rotor.

Conventionally, a starter or an ACG starter has been used to start an engine of a motorcycle or the like. "ACG" is an abbreviation for "Alternating Current Generator", and the ACG starter operates as a starter motor that rotates the crankshaft when the engine is started, and operates as a generator that charges the in-vehicle battery after the engine is started. .. In addition, the ACG starter detects the position of the crank and causes the in-vehicle controller to ignite the optimum plug and inject fuel.

For example, Patent Document 1 describes a rotary electric machine used for starting an engine. The rotary electric machine described in Patent Document 1 includes a rotor, a stator, and a sensor unit. The sensor unit is provided with a plurality of covers extending in the axial direction of the stator, and a sensor for detecting the rotational state of the rotor is housed inside these covers.

Then, each cover is inserted and fixed in the gap portion between the adjacent teeth from the axial direction of the stator. Specifically, a protrusion is provided at the tip of the tooth so as to project in the circumferential direction of the stator, and the cover is attached so as to sandwich the protrusion from the radial direction of the stator.

International Publication No. 2016/181655

However, in the rotary electric machine described in Patent Document 1 described above, the radial inside of the case forming the sensor unit is fixed to the stator by a fixing bolt, and the cover is inserted into the gap portion of the teeth on the radial outside of the case. Is placed. That is, the sensor unit described in Patent Document 1 is supported by the stator in a so-called "cantilever state", and the sensor is arranged at a portion on the free end side.

Further, a cover made of a resin material for accommodating the sensor is attached so as to be in direct contact with and slide with respect to the protruding portion of the stator formed by laminating a plurality of electromagnetic steel sheets.

As a result, the radial outer side (free end side) of the case forming the sensor unit rattles against the stator due to vibration or the like, and the resin cover rubs against the metal stator and comes into contact with the stator of the cover. There was a risk that the part would wear early. Therefore, the cover becomes loose in the radial direction of the stator, and the electrical connection between the sensor housed inside the cover and the electric circuit component is cut off (disconnection, etc.), or the sensor is moved in the radial direction of the stator. There was a risk that it would shift to.

An object of the present invention is to provide a rotary electric machine capable of preventing rattling in the radial direction of the stator of the sensor accommodating portion forming the sensor unit, improving the durability of the sensor unit and improving the detection accuracy. ..

In the rotary electric machine of the present invention, a stator, a rotor having a plurality of magnets that rotate with respect to the stator and are arranged so that N poles and S poles appear alternately in the rotation direction, and a rotor mounted on the stator are described. A rotary electric machine including a sensor unit for detecting the rotational state of the rotor, wherein the stator has an annular main body fixed to an object to be mounted and radially outwardly projected from the main body. The sensor unit has a plurality of teeth, an insulator mounted on the teeth, and a coil wound around the teeth via the insulator, and the sensor unit has a first fixing portion fixed to the main body portion. , A sensor accommodating portion provided between the sensor substrate to which the sensor element is electrically connected and the tip portions of adjacent teeth among the plurality of teeth, and accommodating the sensor substrate, and the sensor accommodating portion. The sensor accommodating portion is provided with a second fixing portion to be fixed to the mounting object, the tip portion having a protruding portion protruding in the circumferential direction of the main body portion, and the sensor accommodating portion of the main body portion. The first contact portion that comes into contact with the protrusion from the inside of the protrusion in the radial direction and the second contact portion that comes into contact with the protrusion from the outside of the protrusion in the radial direction of the main body. It is characterized in that the insulator is interposed between the protrusion and the first contact portion and at least one of the protrusion and the second contact portion. do.

According to the rotary electric machine of the present invention, the sensor unit is provided in the first fixing portion fixed to the main body portion of the stator and the second fixing portion provided in the sensor accommodating portion accommodating the sensor substrate and fixed to the object to be mounted. An insulator is provided between the protruding portion of the tooth and the first contact portion of the sensor accommodating portion, and between the protruding portion of the tooth and the second contact portion of the sensor accommodating portion, at least one of them. Is intervening.

As a result, the sensor housing is prevented from rattling in the radial direction of the stator, and problems such as damage to the sensor element, misalignment, and cracks in the solder of the sensor board are suppressed. Be done. Therefore, it is possible to improve the durability and the detection accuracy of the sensor unit.

Further, even if the sensor accommodating portion rattles with respect to the stator, the insulator is provided between at least one of the protrusion and the first contact portion and between the protrusion and the second contact portion. Since it is interposed, it is possible to suppress wear of the contact portion of the sensor accommodating portion with the stator.

It is a perspective view which shows the rotary electric machine which concerns on this invention. It is explanatory drawing explaining the number of slots and the number of poles. FIG. 3 is a partial cross-sectional view of the rotary electric machine of FIG. 1 as viewed from the side. It is explanatory drawing explaining the arrangement relation of a sensor element and a magnet. It is a perspective view which shows the housing of a sensor unit by itself. FIG. 3 is a partially enlarged cross-sectional view taken along the line AA of FIG. It is an enlarged view of the broken line circle B part of FIG. (A) and (b) are perspective views for explaining the procedure for mounting the sensor unit on the stator. It is sectional drawing corresponding to FIG. 7 which shows Embodiment 2. FIG.

Hereinafter, Embodiment 1 of the present invention will be described in detail with reference to the drawings.

1 is a perspective view showing a rotary electric machine according to the present invention, FIG. 2 is an explanatory view explaining the number of slots and the number of poles, and FIG. 3 is a partial cross-sectional view of the rotary electric machine of FIG. 1 as viewed from the side. 4 is an explanatory view explaining the arrangement relationship between the sensor element and the magnet, FIG. 5 is a perspective view showing the housing of the sensor unit as a single unit, and FIG. 6 is a partially enlarged cross-sectional view taken along the line AA of FIG. 7 is an enlarged view of the broken line circle B of FIG. 6, and FIGS. 8A and 8B are perspective views illustrating a procedure for mounting the sensor unit on the stator.

The rotary electric machine 10 shown in FIGS. 1 to 3 is a so-called ACG starter, which is used for a starter and a generator of a motorcycle or the like (not shown). Specifically, the rotary electric machine 10 adopts the same structure as the outer rotor type brushless motor. When the engine (not shown) is started, it operates as a starter motor by supplying a drive current from an in-vehicle battery (not shown), and after the engine is started, it operates as a generator by the driving force of the engine. do.

The rotary electric machine 10 is formed in a substantially flat disk shape as a whole, and is arranged at an axial end portion of a crankshaft (not shown) forming an engine. Specifically, the rotary electric machine 10 has a stator 20 fixed to a mounting stay ST (see the two-dot chain line in FIG. 3) provided inside a crankcase (not shown) and a stator fixed to a crankshaft. It includes a rotor 30 that rotates relative to 20. Further, the stator 20 is equipped with a sensor unit 40 that detects the rotational state of the rotor 30.

As a result, when operating as a starter, a drive current is supplied to the rotary electric machine 10 at a predetermined timing, and the crankshaft is rotated along with the rotation of the rotor 30. On the contrary, when operating as a generator, the engine is driven at predetermined ignition timing and fuel injection timing, and the rotor 30 is rotated with the rotation of the crankshaft.

The stator 20 includes a stator core 21 formed by laminating a plurality of steel plates (magnetic materials). The stator core 21 includes a main body portion 21a formed in an annular shape, and a plurality of teeth 21b protruding radially outward of the main body portion 21a. Specifically, a total of 18 teeth 21b are provided, and the base end portion of the teeth 21b is integrally connected to the main body portion 21a. In other words, the stator core 21 is provided with a total of 18 slots SL (see FIG. 2).

In the slot SL, a U-phase coil Cu corresponding to the U-phase, a V-phase coil Cv corresponding to the V-phase, and a W-phase coil Cw corresponding to the W-phase are arranged in order in the circumferential direction of the stator core 21, respectively. ing. Specifically, each coil Cu, Cv, Cw is like U-phase coil Cu, V-phase coil Cv, W-phase coil Cw, U-phase coil Cu, V-phase coil Cv, etc. with respect to the rotation direction of the rotor 30. The teeth 21b are wound in a concentrated winding so that they appear alternately one phase at a time (see FIG. 2). Therefore, the thickness dimension of the main body portion (the portion around which the coil is wound) of the teeth 21b along the circumferential direction of the stator 20 is relatively thin.

The tip portion 21c (see FIG. 2) of the teeth 21b is integrally provided with protruding portions 21d protruding from both sides of the stator 20 (main body portion 21a) in the circumferential direction. The thickness dimension (length dimension) of the protruding portion 21d along the circumferential direction of the stator 20 is thicker than the thickness dimension of the main body portion of the teeth 21b. As a result, the distance between the adjacent teeth 21b can be narrowed in the protruding portion 21d. As a result, the rotor 30 can rotate smoothly while the pulsation (cogging) is suppressed.

A total of 18 teeth 21b are each equipped with an insulator 22 made of an insulator such as plastic, as shown in FIG. The insulator 22 is thin and covers the periphery of the teeth 21b and the outer peripheral portion of the main body portion 21a (see FIG. 1). However, in the portion of the protruding portion 21d of the teeth 21b, as shown in FIG. 7, the insulator 22 is mounted only around the back surface BF of the protruding portion 21d. That is, the part of the first side surface SS1 and the part of the second side surface SS2 of the protrusion 21d along the circumferential direction of the stator 20 and the part of the counter surface AF of the magnet MG (see FIG. 2) of the protrusion 21d are Not covered by insulator 22.

The insulator 22 insulates between the teeth 21b and each coil Cu, Cv, Cw. That is, each coil Cu, Cv, Cw is wound around each tooth 21b via an insulator 22. Here, in FIG. 1, in order to make it easy to understand the wound state of each coil Cu, Cv, Cw, each coil Cu, Cv, Cw is shaded. Further, in FIG. 6, in order to make it easy to understand the arrangement relationship between the teeth 21b and the sensor accommodating portion 47, the illustrations of the coils Cu, Cv, and Cw are omitted.

As shown in FIGS. 1 to 3, the rotor 30 includes a rotor main body 31. The rotor main body 31 is formed into a substantially bowl shape by pressing a relatively thick steel plate (magnetic material), and has a substantially disk-shaped bottom wall portion 31a and an outer peripheral portion of the bottom wall portion 31a. It is provided with a tubular side wall portion 31b that rises vertically from the surface.

Further, at the center of rotation of the bottom wall portion 31a, a cylindrical boss portion 32 to which the axial end portion of the crankshaft is fixed is fixed. As a result, the crankshaft is rotated as the rotor body 31 rotates. Here, the wall thickness of the boss portion 32 is thicker than the wall thickness of the rotor main body 31, and the weight of the boss portion 32 is relatively large. As a result, the fixing strength between the rotary electric machine 10 and the crankshaft is sufficiently secured, the occurrence of rotation unevenness at the time of high-speed rotation or the like is suppressed, and the load applied to both the crankshaft and the rotary electric machine 10 is reduced.

A total of 12 magnets MG are mounted on the radial inside of the cylindrical side wall portion 31b, that is, on the stator core 21 side of the side wall portion 31b. These magnets MG employ ferrite magnets. In addition, other magnets such as neodymium magnets can also be used. As shown in the shaded portion of FIG. 2, the magnet MG is formed in a substantially arc shape following the shape of the cylindrical side wall portion 31b (see FIG. 1). These magnets MG are firmly fixed to the side wall portion 31b with an adhesive or the like (not shown).

Further, a total of 12 magnets MG are pressed from the radial inside of the rotor main body 31 toward the side wall portion 31b by the magnet holder HD formed in a substantially cylindrical shape. Therefore, each magnet MG is prevented from falling off from the side wall portion 31b. The magnet holder HD is formed of a flexible thin stainless steel plate, SP material (cold rolled steel plate), etc., and also has a function of positioning each magnet MG at equal intervals in the circumferential direction of the side wall portion 31b. I have. This facilitates the fixing work to the side wall portion 31b of each magnet MG and improves the assembling workability of the rotary electric machine 10.

Here, as shown in FIG. 4, 11 out of a total of 12 magnet MGs have only one magnetic pole at the facing portion SF facing the stator core 21 (each sensor Su, Sv, Sw, Sr). It is a standard magnet 33. On the other hand, the other one of the total of 12 magnets MG is a two-stage magnet 34 having two magnetic poles on the facing portion SF facing the stator core 21 (each sensor Su, Sv, Sw, Sr). ing.

The plurality of magnets MG (11 standard magnets 33 and one two-stage magnet 34) are arranged so that N poles and S poles appear alternately in the rotation direction of the rotor 30.

As shown in FIGS. 1 and 3, the sensor unit 40 is provided on one side in the axial direction of the stator core 21, that is, on the side opposite to the side of the bottom wall portion 31a along the axial direction of the stator core 21. The sensor unit 40 is provided so as to cover a part of the stator 20 along the circumferential direction.

The sensor unit 40 includes a housing 41 formed in a substantially T shape by an insulator such as plastic. As shown in FIGS. 1 and 5, the housing 41 includes a first fixing portion 42, a second fixing portion 43, a bridging portion 44, and a sensor holder portion 45.

The first fixing portion 42 is formed in a substantially fan shape, and is firmly fixed to the main body portion 21a of the stator core 21 by a fixing bolt BT (see FIG. 1). The fixing bolt BT is screwed from the other side (bottom wall portion 31a side) of the stator 20 in the axial direction by a fastening jig (not shown). In this way, the sensor unit 40 is fixed to the stator core 21, that is, the non-rotating portion of the rotary electric machine 10.

The second fixing portion 43 is formed in a substantially annular shape, and is provided so as to project radially outward from the side wall portion 31b (see FIG. 1). Then, the second fixing portion 43 is firmly fixed to the mounting stay ST (see the two-dot chain line in FIG. 3) provided inside the crankcase by a fixing bolt (not shown).

In this way, the portions on both sides of the sensor unit 40 that sandwich the bridging portion 44 and the sensor holder portion 45 are fixed to the mounting stay ST inside the crankcase, which is a non-rotating portion. That is, the sensor unit 40 according to the present embodiment is not supported in the so-called "cantilever state" as in the past, but is supported in the so-called "double-sided state". Here, the mounting stay ST provided inside the crankcase constitutes the mounting object in the present invention.

As shown in FIG. 5, a bridging portion 44 and a sensor holder portion 45 are arranged between the first fixing portion 42 and the second fixing portion 43. The bridging portion 44 is provided inside the stator core 21 in the radial direction, that is, a portion closer to the first fixing portion 42, and the sensor holder portion 45 is provided outside the radial direction of the stator core 21, that is, a portion closer to the second fixing portion 43. ing.

The bridging portion 44 is formed in a substantially plate shape, and is provided so as to cover the portions of the coils Cu, Cv, and Cw forming the stator 20. The bridging portion 44 supports the inside of the sensor holder portion 45 (on the side of the first fixing portion 42). Here, the bridging portion 44 is in a non-contact state with respect to each coil Cu, Cv, Cw, and may damage the insulating coating (not shown) on the surface of each coil Cu, Cv, Cw. There is no.

The sensor holder portion 45 is provided on the radially outer portion of the stator core 21, and the outer side of the sensor holder portion 45 (on the side of the second fixing portion 43) is supported by the second fixing portion 43. That is, the radial inner side and the radial outer side of the sensor holder portion 45 are supported by both the first fixing portion 42 and the second fixing portion 43. Therefore, the sensor holder portion 45 is prevented from rattling with respect to the stator 20 due to vibration or the like.

The sensor holder portion 45 includes a holder main body 46 formed in a substantially arc shape, and three sensor accommodating portions 47 extending in the axial direction of the stator 20 from the holder main body 46. That is, the second fixing portion 43 is integrally provided in the three sensor accommodating portions 47 via the holder main body 46, whereby rattling of the three sensor accommodating portions 47 with respect to the stator 20 is effectively suppressed. Specifically, the three sensor accommodating portions 47 extend from the holder main body 46 toward the bottom wall portion 31a of the rotor main body 31 (see FIG. 3).

The three sensor accommodating portions 47 are all formed in the same shape, and as shown in FIGS. 5 and 6, have a hollow rod shape extending in the axial direction of the stator 20. The base end portion of the sensor accommodating portion 47 is integrally connected to the holder main body 46, and the sensor accommodating portion 47 is formed in the same cross-sectional shape from the proximal end portion to the tip end portion. A sensor board SB on which each sensor Su, Sv, Sw, Sr (see FIGS. 3 and 4) as a sensor element is mounted is housed inside the sensor housing unit 47.

The sensor substrate SB on which the sensors Su, Sv, Sw, and Sr are mounted is accurately positioned at a predetermined position inside the sensor accommodating portion 47 by the cured mold resin MR. Further, each sensor Su, Sv, Sw, Sr side mounted on the sensor board SB faces the magnet MG of the rotor 30.

A first contact portion 47a and a second contact portion 47b are integrally provided on both sides (left and right sides in FIG. 6) of the sensor accommodating portion 47 along the longitudinal direction of the holder main body 46. These first and second contact portions 47a and 47b are projected from both sides of the sensor accommodating portion 47 at predetermined heights, respectively, and are the first contact portion 47a and the first contact portion 47a along the lateral direction of the holder main body 46. 2 The tip portion of the protruding portion 21d of the teeth 21b is inserted into the recessed portion between the contact portion 47b (see FIG. 6).

Here, both the first contact portion 47a and the second contact portion 47b are provided over the entire longitudinal direction of the sensor accommodating portion 47. This makes it possible to simplify the shape of the upper and lower molds (not shown) used when injection molding the sensor unit 40. Therefore, it is possible to reduce the manufacturing cost of the sensor unit 40.

Then, as shown in FIGS. 6 and 7, the first contact portion 47a of the sensor accommodating portion 47 is formed from the inside of the protruding portion 21d to the protruding portion 21d in the radial direction of the main body portion 21a forming the stator core 21. On the other hand, they are in contact with each other via the insulator 22. On the other hand, the second contact portion 47b of the sensor accommodating portion 47 is directly in contact with the protruding portion 21d from the outside of the protruding portion 21d in the radial direction of the main body portion 21a forming the stator core 21. There is.

Specifically, as shown in FIG. 7, the first contact portion 47a is substantially linearly contacted with the back surface BF of the protruding portion 21d at the contact portion CP1 via the insulator 22. Here, the cross-sectional shape of the first contact portion 47a is a substantially semicircular shape. As a result, the first contact portion 47a and the insulator 22 are in a state of being substantially in contact with each other.

Further, the second contact portion 47b is in direct contact with the second side surface SS2 of the protruding portion 21d at the portion of the contact portion CP2. Here, the cross-sectional shape of the second contact portion 47b is also a substantially semicircular shape. As a result, the second contact portion 47b and the second side surface SS2 are in a state of being substantially in contact with each other.

Therefore, it is possible to prevent the three sensor accommodating portions 47 of the sensor unit 40 mounted on the stator 20 from reciprocating in small steps in the direction of the arrow Mout and the direction of Min in FIG. That is, the three sensor accommodating portions 47 are prevented from rattling in the radial direction of the stator 20.

Then, the insulator 22 is interposed only between the protruding portion 21d and the first contact portion 47a, and the contact portion CP1 portion and the contact portion CP2 portion are brought into substantially linear contact with each other. Therefore, it is possible to reduce the mounting load when mounting the sensor accommodating portion 47 between the tip portions 21c of the adjacent teeth 21b, and it is possible to facilitate the mounting work of the sensor unit 40 on the stator 20. .. In particular, since the first contact portion 47a is slidably contacted with the insulator 22, the wear of the first contact portion 47a is effectively suppressed.

As shown in FIG. 3, the sensor substrate SB accommodated in each of the three sensor accommodating portions 47 provided in the holder main body 46 has a U-phase sensor Su, a V-phase sensor Sv, and a W-phase sensor Sw, respectively. Is implemented. Further, a rotation sensor Sr for detecting ignition timing and fuel injection timing (detecting the position of the crank) is also mounted on the sensor board SB (leftmost side in FIG. 3) corresponding to the W phase. That is, these four sensors Su, Sv, Sw, and Sr are each electrically connected to the sensor substrate SB.

Here, the U-phase, V-phase, and W-phase sensors Su, Sv, and Sw are provided on the tip end side of the sensor accommodating portion 47, and are arranged side by side in the rotation direction of the rotor 30. There is. Further, the rotation sensor Sr is arranged in a portion on the base end side of the sensor accommodating portion 47.

These four sensors Su, Sv, Sw, and Sr are Hall elements (sensor elements) having the same configuration, respectively. Specifically, an alternating detection type (bipolar) Hall element that is switched on / off by a magnetic pole (N pole / S pole) is adopted. For example, when the N pole is detected, an "on signal (1)" is generated, and when the S pole is detected, an "off signal (0)" is generated.

As a result, each sensor Su, Sv, Sw, Sr outputs a rectangular wave signal (not shown) as the rotor 30 having a total of 12 magnets MG (see FIG. 4) rotates. Therefore, the in-vehicle controller (not shown) grasps the rotational state of the rotor 30 based on the input of these square wave signals, and supplies the drive current to each coil Cu, Cv, Cw at the optimum timing. can do. In addition, the in-vehicle controller can control the igniter and the fuel pump (not shown) by grasping the ignition timing and the fuel injection timing.

As shown in FIGS. 3 and 6, the U-phase sensor Su, the V-phase sensor Sv, the W-phase sensor Sw, and the rotation sensor Sr are located at the tips 21c of the adjacent teeth 21b via the sensor substrate SB, respectively. It is in the space (the part of the slot SL). Here, the distance L between the W-phase sensor Sw and the rotation sensor Sr along the axial direction of the stator core 21 is set to about 5.0 mm.

In this way, each of the sensors Su, Sv, Sw, and Sr is fixed to the stator core 21, and only one of the rotation sensors Sr is a rotor for each of the driving sensors Su, Sv, Sw. It is arranged so as to be offset in the axial direction of 30. Here, each of the sensors Su, Sv, Sw, and Sr is adapted to face a total of 12 magnets MG (see FIG. 4) from the inside in the radial direction of the rotary electric machine 10. As a result, each of the sensors Su, Sv, Sw, and Sr outputs a rectangular wave signal due to a change in the magnetic poles (N pole / S pole) accompanying the rotation of the rotor 30.

As shown in FIG. 4, each sensor Su, Sv, Sw, Sr moves (relatively rotates) relative to a total of 12 magnets MG, and reaches the edge portions PN, PS of each magnet MG. Sometimes, each magnetic pole is detected. For example, each sensor Su, Sv, Sw, Sr generates an "on signal (1)" when it approaches the edge portion PN of the N pole, and an "off signal (0)" when it approaches the edge portion PS of the S pole. "Is generated.

The three U-phase sensors Su, the V-phase sensor Sv, and the W-phase sensor Sw are respectively opposed to the first facing portion 34a (S pole) of the two-stage magnet 34, and one rotation. The sensor Sr is adapted to face the second facing portion 34b (N pole) of the two-stage magnet 34.

The positional relationship between the total of 12 magnets MG and each sensor Su, Sv, Sw, Sr is the positional relationship shown in FIG. FIG. 4 is a schematic view of the cylindrical side wall portion 31b (see FIG. 3) of the rotor main body 31 developed in a plane.

The width dimension W of each magnet MG is set to about 30 mm, and the height dimension H of each magnet MG is set to about 25 mm. Further, the spacing dimension G of each magnet MG along the rotation direction of the rotor 30 is set to about 2 mm. The pitch P1 of the edge portions PN and PS of each magnet MG is set to 30 degrees. This pitch P1 (30 degrees) coincides with the arrangement interval of each magnet MG along the rotation direction of the rotor 30, and is obtained based on "360 degrees ÷ 12 poles".

On the other hand, the pitch P2 of each of the driving sensors Su, Sv, Sw is set to 20 degrees. This pitch P2 (20 degrees) coincides with the arrangement interval of each slot SL (see FIG. 2) along the rotation direction of the rotor 30, and is obtained based on “360 degrees ÷ 18 slots”. As described above, the rotary electric machine 10 in the present embodiment forms a brushless motor having [12 poles and 18 slots]. This enables smooth rotary drive in which the generation of cogging torque is suppressed.

As shown in FIG. 4, in the standard magnet 33 and the two-stage magnet 34, the thin shaded portion has an S pole and the dark shaded portion has an N pole. The facing portion SF of the standard magnet 33 is magnetized to one pole, and the facing portion SF of the two-stage magnet 34 is magnetized to two poles.

Specifically, the facing portion SF of the two-stage magnet 34 is provided with a first facing portion 34a that occupies a large surface area and a second facing portion 34b having a surface area smaller than the surface area of the first facing portion 34a. There is. The first facing portion 34a is magnetized to the S pole, the second facing portion 34b is magnetized to the N pole, and the magnetic poles of the first facing portion 34a and the magnetic poles of the second facing portion 34b are different from each other. ..

The second facing portion 34b of the two-stage magnet 34 is much smaller than the first facing portion 34a. In other words, the second facing portion 34b extends in a band shape in the rotation direction of the rotor 30. A boundary portion BL indicating the boundary of the magnetic poles is provided between the first facing portion 34a (large) and the second facing portion 34b (small). Here, the boundary portion BL provided on the facing portion SF of the two-stage magnet 34 is a boundary line between the first facing portion 34a magnetized on the S pole and the second facing portion 34b magnetized on the N pole. It has become.

Further, as shown in FIGS. 3 and 4, a detection boundary line LN is formed in the vicinity of the boundary portion BL as shown by a virtual line (dashed-dotted line). The detection boundary line LN is arranged exactly in the middle between the W phase sensor Sw and the rotation sensor Sr, and the first facing portion 34a side (lower side in the figure) of the detection boundary line LN is each sensor for driving. Su, Sv, and Sw are the first detection regions AR1 that can detect changes in the magnetic poles. On the other hand, the second facing portion 34b side (upper side in the figure) of the detection boundary line LN is the second detection region AR2 in which the rotation sensor Sr can detect the change of the magnetic pole. The detection boundary line LN is slightly offset (shifted) toward the first facing portion 34a with respect to the boundary portion BL.

Here, in order to improve the detection accuracy of each of the driving sensors Su, Sv, Sw and the detection accuracy of the rotation sensor Sr, the position of the detection boundary line LN and the position of the boundary portion BL with respect to the axial direction of the rotor 30 It is desirable to make a perfect match. By doing so, it is possible to accurately detect each magnetic pole without being affected by the other magnetic pole. However, in reality, it is difficult to completely match the position of the detection boundary line LN with the position of the boundary portion BL because the dimensional accuracy of the components varies and the rotor 30 is misaligned with respect to the stator 20. be.

Therefore, in design, the first sensor on the second facing portion 34b is centered on the detection boundary line LN so that each of the driving sensors Su, Sv, and Sw can detect the change of the magnetic pole with higher accuracy. The S pole of the facing portion 34a is slightly protruded. As a result, the detection accuracy of each of the driving sensors Su, Sv, and Sw is sufficiently ensured, and the rotary electric machine 10 can be reliably driven as a starter motor.

Here, as shown in FIG. 4, the pitch P2 of each of the driving sensors Su, Sv, and Sw is 20 degrees. Therefore, the driving sensors Su, Sv, and Sw do not face one magnet MG at the same time. Then, each of the driving sensors Su, Sv, and Sw outputs a square wave signal at different timings, so that the in-vehicle controller can grasp the rotation state (rotation direction, rotation speed, etc.) of the rotor 30. There is.

Here, the rotation sensor Sr faces the N pole three times in a row at the portion of the two-stage magnet 34 while the rotor 30 makes one rotation. That is, when the length of the rectangular wave signal output by each of the driving sensors Su, Sv, Sw is "1", the length of each of the driving sensors Su, Sv, Sw is always "1". Output a square wave signal. On the other hand, the rotation sensor Sr outputs a rectangular wave signal having a length of "3" when facing the N pole three times in a row. Therefore, the vehicle-mounted controller can grasp that the rotor 30 has made one rotation based on the input of the long rectangular wave signal from the rotation sensor Sr.

In this way, the rotary electric machine 10 according to the present embodiment can be efficiently rotationally driven as a starter motor, and can reliably detect the ignition timing and the fuel injection timing.

As shown in FIG. 4, the rotation sensor Sr is slightly opposite to the first facing portion 34a side from the second facing portion 34b magnetized at the N pole in the axial direction of the rotor 30. It is placed in a position that protrudes. As a result, the rotation sensor Sr is less likely to be affected by the S pole of the first facing portion 34a slightly protruding toward the second facing portion 34b with the detection boundary line LN as the center. Therefore, the decrease in the detection accuracy of the rotation sensor Sr is effectively suppressed.

Next, the procedure for assembling the rotary electric machine 10 formed as described above, particularly the procedure for mounting the sensor unit 40 on the stator 20, will be described in detail with reference to the drawings. In the sensor unit 40 in FIG. 8, the mold resin MR (see FIGS. 1 and 6) is not shown.

First, as shown in FIG. 8A, the stator 20 and the sensor unit 40, which are assembled through different manufacturing steps, are prepared. Next, the three sensor accommodating portions 47 provided in the sensor unit 40 are made to face the stator 20 from one side in the axial direction (upper side in the drawing). At this time, the tip of each sensor accommodating portion 47 is directed between the tip portions 21c of the adjacent teeth 21b. Then, as shown by the arrow M, the three sensor accommodating portions 47 are inserted between the tip portions 21c, respectively.

As a result, as shown in FIGS. 6 and 7, the protruding portion 21d of the teeth 21b is arranged so as to be sandwiched between the first contact portion 47a and the second contact portion 47b of the sensor accommodating portion 47. Will be done. At this time, the first contact portion 47a is slidably contacted with the insulator 22, and the second contact portion 47b is slidably contacted with the protruding portion 21d.

Here, the insertion portion of the sensor accommodating portion 47 into the stator 20 is a portion where the spacing dimension of the protruding portion 21d is larger than that of the other portion (spacing dimension L1). Specifically, the sensor accommodating portion 47 is inserted into a portion where the distance dimension of the protruding portion 21d is L2 (L2> L1). The size of the spacing dimension L2 is approximately twice the size of the spacing dimension L1, and three portions of the spacing dimension L2 are continuously provided in the circumferential direction of the stator 20. Therefore, the portion of the interval dimension L2 into which the sensor accommodating portion 47 is inserted is conspicuous in appearance of the stator 20, and the mounting workability is good.

After that, the sensor unit 40 is abutted against the stator 20, and the insertion operation between the tip portions 21c (between the protruding portions 21d) of the three sensor accommodating portions 47 is completed. Next, in the state where the insertion operation is completed, the sensor unit 40 is finally fixed to the stator 20 by using the fixing bolt BT. As a result, as shown in FIG. 8B, the mounting of the sensor unit 40 on the stator 20 is completed.

As described in detail above, according to the rotary electric machine 10 according to the present embodiment, the sensor unit 40 accommodates the first fixing portion 42 fixed to the main body portion 21a of the stator 20 and the sensor accommodating the sensor substrate SB. A second fixing portion 43 provided in the portion 47 and fixed to the mounting stay ST is provided, a protruding portion 21d is arranged between the first contact portion 47a and the second contact portion 47b, and the teeth 21b protrudes. An insulator 22 is interposed between the portion 21d and the first contact portion 47a of the sensor accommodating portion 47.

As a result, the sensor accommodating portion 47 is prevented from rattling in the radial direction of the stator 20, and the sensors Su, Sv, Sw, and Sr are prevented from being damaged or misaligned. Further, it is possible to suppress the occurrence of defects such as cracks in the solder (not shown) of the sensor board SB. Therefore, it is possible to improve the durability and the detection accuracy of the sensor unit 40.

Further, even if the sensor accommodating portion 47 rattles with respect to the stator 20, the insulator 22 is interposed between the protruding portion 21d and the first contact portion 47a, so that the sensor accommodating portion 47 and the stator 20 It is possible to suppress the wear of the contact portion of the.

Further, according to the rotary electric machine 10 according to the present embodiment, since the insulator 22 is interposed only between the protruding portion 21d and the first contact portion 47a, the insulator 22 is interposed, so that the sensor accommodating portion 47 comes into contact with the stator 20. It is possible to simplify the shape of the insulator 22 and reduce the size and weight of the insulator 22 while suppressing the wear of the portion.

Further, according to the rotary electric machine 10 according to the present embodiment, the sensor accommodating portion 47 extends in the axial direction of the stator 20, and the first abutting portion 47a and the second abutting portion 47b are the sensor accommodating portions, respectively. Since it is provided in the entire longitudinal direction of the 47, rattling in the radial direction of the stator 20 of the sensor accommodating portion 47 can be more effectively suppressed. Further, the shape of the upper and lower molds used for molding the sensor unit 40 can be simplified, and the manufacturing cost can be reduced.

Next, Embodiment 2 of the present invention will be described in detail with reference to the drawings. The parts having the same functions as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

FIG. 9 shows a cross-sectional view corresponding to FIG. 7 showing the second embodiment.

As shown in FIG. 9, in the second embodiment, the shape of the protrusion 50 provided on the teeth 21b and the shape of the insulator 51 are different. Specifically, the protruding height of the protruding portion 50 along the circumferential direction of the stator 20 is slightly smaller than the protruding height of the protruding portion 21d (see FIG. 7) of the first embodiment. The insulator 51 is also provided so as to cover the portion of the first side surface SS1 and the portion of the second side surface SS2 of the protrusion 50.

As a result, when the sensor unit 40 is mounted on the stator 20, both the first contact portion 47a and the second contact portion 47b of the sensor accommodating portion 47 have the contact portion CP1 and the contact portion CP2 with respect to the insulator 51. At each part, they are in contact with each other. That is, in the second embodiment, the insulator 51 is interposed between the protrusion 50 and the first contact portion 47a and between the protrusion 50 and the second contact portion 47b.

Also in the second embodiment formed as described above, substantially the same effect as that of the first embodiment described above can be obtained. In addition to this, in the second embodiment, when the sensor unit 40 is mounted on the stator 20, both the first and second contact portions 47a and 47b are slidably contacted with the insulator 51, so that the sensor accommodating portion 47 It is possible to more reliably suppress the wear of the contact portion with the stator 20.

Further, even if the sensor accommodating portion 47 rattles with respect to the stator 20, both the first and second contact portions 47a and 47b are in contact with the insulator 51, so that abnormal noise is generated due to vibration or the like. Can be reliably suppressed.

It goes without saying that the present invention is not limited to each of the above embodiments and can be variously modified without departing from the gist thereof. For example, in each of the above embodiments, the first and second contact portions 47a and 47b are provided in the entire longitudinal direction of the sensor accommodating portion 47, respectively, but the present invention is not limited to this. The first and second contact portions may be partially provided in the longitudinal direction of the sensor accommodating portion, respectively. Further, only one of the first and second contact portions may be partially provided in the longitudinal direction of the sensor accommodating portion. In this case, in order to suppress rattling of each sensor Su, Sv, Sw, Sr, it is desirable that the first and second contact portions are provided in the vicinity of each sensor Su, Sv, Sw, Sr.

Further, in each of the above embodiments, the sensors Su, Sv, Sw, and Sr are mounted directly on the sensor substrate SB, but the present invention is not limited to this, and the sensor element has a lead wire. It can also be applied to those that are electrically connected to the sensor substrate via.

Further, in each of the above embodiments, the rotary electric machine 10 has a brushless motor structure of "12 poles and 18 slots", but the present invention is not limited to this, and the number of other poles and the number of other slots are not limited to this. It doesn't matter.

Further, in each of the above embodiments, the rotary electric machine 10 is used as a starter for a motorcycle or the like and an ACG starter used for a generator, but the present invention is not limited to this, and for example, agricultural machinery such as a cultivator is shown. It can also be applied to an ACG starter used for starting an engine of an outboard motor of a small vessel or a small vessel.

In addition, the material, shape, dimensions, number, installation location, etc. of each component in each of the above embodiments are arbitrary as long as the present invention can be achieved, and are not limited to the above embodiments.

10: Rotating electric machine, 20: Stator, 21: Stator core, 21a: Main body, 21b: Teeth, 21c: Tip, 21d: Protruding, 22: Insulator, 30: Rotor, 31: Rotor body, 31a: Bottom wall , 31b: Side wall, 32: Boss, 33: Standard magnet (magnet), 34: Two-stage magnet (magnet), 34a: First facing part, 34b: Second facing part, 40: Sensor unit, 41: Housing , 42: 1st fixing part, 43: 2nd fixing part, 44: bridging part, 45: sensor holder part, 46: holder body, 47: sensor accommodating part, 47a: 1st contact part, 47b: 2nd hit Contact part, 50: Projection part, 51: Insulator, AF: Counter surface, AR1: First detection area, AR2: Second detection area, BF: Back surface, BL: Boundary part, BT: Fixing bolt, CP1, CP2: Contact Part, Cu: U-phase coil (coil), Cv: V-phase coil (coil), Cw: W-phase coil (coil), HD: magnet holder, LN: detection boundary line, MG: magnet, MR: mold resin, SB : Sensor board, SF: Opposite part, SL: Slot, Sr: Rotation sensor (sensor element), SS1: 1st side surface, SS2: 2nd side surface, ST: Mounting stay (mounting object), Su: U-phase sensor (Sensor element), Sv: V-phase sensor (sensor element), Sw: W-phase sensor (sensor element)

Claims (3)

With the stator,
A rotor having a plurality of magnets that rotate with respect to the stator and are arranged so that N poles and S poles appear alternately in the rotation direction.
A sensor unit mounted on the stator and detecting the rotational state of the rotor, and
It is a rotary electric machine equipped with
The stator is
An annular body that is fixed to the object to be mounted, and
A plurality of teeth radially protruding outward in the radial direction of the main body, and
The insulator attached to the teeth and
A coil wound around the tooth via the insulator,
Have,
The sensor unit is
The first fixing portion fixed to the main body portion and
With the sensor board to which the sensor element is electrically connected,
A sensor accommodating portion provided between the tips of adjacent teeth among the plurality of teeth and accommodating the sensor substrate, and a sensor accommodating portion.
A second fixing portion provided in the sensor accommodating portion and fixed to the mounting object, and a second fixing portion.
Equipped with
The tip portion has a protruding portion protruding in the circumferential direction of the main body portion.
The sensor accommodating portion includes a first contact portion that comes into contact with the protruding portion from the inside of the protruding portion in the radial direction of the main body portion, and the protruding portion from the outside of the protruding portion in the radial direction of the main body portion. It has a second contact portion to be abutted and has a second contact portion.
The insulator is interposed between the protrusion and the first contact portion and at least one of the protrusion and the second contact portion.
Rotating electric machine. The insulator is interposed only between the protrusion and the first contact portion.
The rotary electric machine according to claim 1. The sensor accommodating portion extends in the axial direction of the stator, and the sensor accommodating portion extends in the axial direction.
The first contact portion and the second contact portion are provided in the entire longitudinal direction of the sensor accommodating portion, respectively.
The rotary electric machine according to claim 1 or 2.

Images