motor

Abstract

To provide a brush motor in which sparks between a segment and a brush are less likely to be generated.SOLUTION: A brush motor comprises: a magnet 6; a plurality of slots T1 to T5; a coil 3 that is wound across two slots of the plurality of slots; a commutator 4 that has a plurality of segments C1 to C10; and a plurality of brushes 7 having contact parts A, B which are in contact with two adjacent segments. Of the two slots (e.g, T2 and T3) across which the coil 3 is wound, a winding direction of a one of the coils (e.g., 32) on one slot (e.g., T2) is a reverse direction to the winding direction of the coil (e.g., 32) on the other slot (e.g., T3). The coil (e.g., 32) wound on one of the one slots (e.g., T2) is connected one segment (e.g., C3) of the two adjacent segments, and the coil (e.g., 32) wound on the other slot (e.g., T3) is connected to the other segment (e.g, C4).SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a motor. [Background technology]

[0002] In a DC motor using a commutator with multiple segments and brushes (i.e., a so-called "brush motor"), the period of torque ripple becomes shorter as the number of poles increases, and this torque ripple can sometimes cause high-frequency noise.

[0003] In addition, if a brush motor is made with a simple concentrated winding coil without multi-polarization, when the brush moves from one segment to another, the brush and the segment may move. between If sparks occur frequently, this can accelerate brush wear and potentially shorten the brush life. In the case of a coil with concentrated winding connection, the potential difference between adjacent segments can become large, and this potential difference can easily cause sparks to occur between the segments and the brushes. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-41389 Summary of the Invention [Problem to be solved by the invention]

[0005] Therefore, the present invention has been made in view of the above background, and an example of an object of the present invention is to provide a brush motor in which sparks are less likely to occur between the segments and the brushes. [Means for solving the problem]

[0006] The above object can be achieved by the present invention as follows. That is, one aspect of the motor of the present invention is a motor including a magnet and a plurality of slots facing the magnet; a coil wound across two of the plurality of slots; a commutator having a plurality of segments; a plurality of brushes each having a contact portion that contacts the plurality of segments in a circumferential direction; Equipped with The winding direction of the coil in one of the two slots across which the coil is wound is opposite to the winding direction of the coil in the other slot, In the circumferential direction, the coil wound around one slot is connected to one of two adjacent segments, and the coil wound around the other slot is connected to the other of the two adjacent segments. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is an exploded perspective view of a motor according to an embodiment of the present invention; [Figure 2] 1 is a schematic diagram showing the mutual relationships (positional relationships, connection relationships) of the components of the armature arranged in the circumferential direction in a motor according to a first embodiment, which is an example of the present invention, with the components being expanded in the left-right direction. [Figure 3] FIG. 2 is a schematic cross-sectional view of a portion of FIG. 1 where the commutator and a plurality of brushes are in contact with each other, taken along a plane perpendicular to the axial direction of the shaft. [Figure 4] This is an explanatory diagram for explaining, in time series, the change in magnetic poles of the slots and the movement of the components of the armature when a predetermined current or voltage is applied to the motor of the first embodiment, and is the first half of the time series (1) to (2). [Figure 5]This is an explanatory diagram for explaining, in time series, the change in magnetic poles of the slots and the movement of the components of the armature when a predetermined current or voltage is applied to the motor of the first embodiment, and is the latter half of the time series (3) to (4). [Figure 6] 10 is a schematic diagram showing the mutual relationships (positional relationships, connection relationships) of the components of the armature arranged in the circumferential direction in a motor according to a second embodiment, which is one example of the present invention, with the components being expanded in the left-right direction. FIG. [Figure 7] This is an explanatory diagram for explaining, in time series, the change in magnetic poles of the slots and the movement of the components of the armature when a predetermined current or voltage is applied to the motor of the second embodiment, and is the first half of the time series (1) to (2). [Figure 8] This is an explanatory diagram for explaining, in time series, the change in magnetic poles of the slots and the movement of the components of the armature when a predetermined current or voltage is applied to the motor of the second embodiment, and is the latter half of the time series (3) to (4). [Figure 9] 10 is a schematic diagram showing the mutual relationships (positional relationships, connection relationships) of the components of the armature arranged in the circumferential direction in a motor according to a third embodiment, which is one example of the present invention, with the components being expanded in the left-right direction. FIG. [Figure 10] This is an explanatory diagram for explaining, in time series, the change in magnetic poles of the slots and the movement of the components of the armature when a predetermined current or voltage is applied to the motor of the third embodiment, and is the first half of the time series (1) to (3). [Figure 11] This is an explanatory diagram for explaining, in time series, the change in magnetic poles of the slots and the movement of the components of the armature when a predetermined current or voltage is applied to the motor of the third embodiment, and is the latter half of the time series (4) to (5). [Figure 12] 10 is a schematic diagram showing the mutual relationships (positional relationships, connection relationships) of the components of the armature arranged in the circumferential direction in a motor according to a fourth embodiment, which is one example of the present invention, with the components expanded in the left-right direction. FIG. [Figure 13]This is an explanatory diagram for explaining, in time series, the change in magnetic poles of the slots and the movement of the components of the armature when a predetermined current or voltage is applied to the motor of the fourth embodiment, and is the first half of the time series (1) to (2). [Figure 14] This is an explanatory diagram for explaining, in time series, the change in magnetic poles of the slots and the movement of the components of the armature when a predetermined current or voltage is applied to the motor of the fourth embodiment, and is the latter half of the time series (3) to (4). [Figure 15] 10 is a schematic diagram showing the mutual relationships (positional relationships, connection relationships) of the components of the armature arranged in the circumferential direction in a motor according to a fifth embodiment, which is one example of the present invention, with the components expanded in the left-right direction. FIG. [Figure 16] FIG. 10 is a schematic diagram showing only the state of current flow when a predetermined current or voltage is applied to a motor according to a fifth embodiment. [Figure 17] 10 is a schematic diagram showing the mutual relationships (positional relationships, connection relationships) of the components of the armature arranged in the circumferential direction in a motor according to a sixth embodiment, which is one example of the present invention, with the components expanded in the left-right direction. FIG. [Figure 18] 10 is a schematic cross-sectional view showing two coils wound around second teeth of a motor according to a sixth embodiment, taken along a plane perpendicular to the direction in which the second teeth extend (radial direction). FIG. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, first to fifth embodiments, which are illustrative aspects of the present invention, will be described with reference to the drawings.

[0009] (First embodiment) Fig. 1 is an exploded perspective view of a motor 1 according to a first embodiment of the present invention, and Fig. 2 is a schematic diagram showing the mutual relationships (positional relationships, connection relationships) of the components of the armature arranged circumferentially in the motor 1, with the components expanded left and right in the circumferential direction. In the following description, the left side (opposite the direction of arrow X) in Fig. 2 will be referred to as one side, and the right side (the side in the direction of arrow X) will be referred to as the other side. The schematic views (in this embodiment, Fig. 2, as well as Figs. 4 and 5 described later) in which the components of the armature are expanded left and right are the same, including in other embodiments.

[0010] As shown in Fig. 1, the motor 1 according to this embodiment is a four-pole, five-slot motor including a rotating armature 10 fixed to a shaft 8 and rotating with it, and a fixed stator 20. In the motor 1, the armature 10 includes a rotor core 2 having a plurality of slots (five in this embodiment) (magnetic pole portions), a coil 3 wound around each of the slots, and a commutator 4 having a plurality of segments (ten in this embodiment). Meanwhile, the stator 20 includes a housing 5, a magnet 6 having a plurality of magnetic poles (four in this embodiment), and a plurality of brushes 7 in contact with the segments of the commutator 4.

[0011] 2 and the subsequent schematic and explanatory diagrams (including other embodiments), the lower solid lines indicate the connecting wiring (also called "crossover wires") 9 between the segments. In addition, in these solid lines, a black dot superimposed on a cross or T-shaped intersection indicates a connected state, and a simple cross intersection without a black dot indicates a non-connected state.

[0012] 2, the rotor core 2 has a plurality of (five in this embodiment) circumferentially arranged slots, designated by first teeth T1 to fifth teeth T5. Coils 31 to 35 are wound around the first teeth T1 to fifth teeth T5, respectively. The winding directions (spiral directions) of the coils 31 to 35 will be described later.

[0013] The commutator 4 has segments C1 to C10 as a plurality of segments arranged in the circumferential direction. The segments C1 to C10 are adapted to come into contact with the contact portions A and B of the plurality of brushes 7 to conduct electricity. The housing 5 houses the armature 10 and also functions as a yoke by being made of a magnetic material such as iron (e.g., ferromagnetic material).

[0014] The magnet 6 is cylindrical and provided on the inner surface of the housing 5. In this embodiment, two different magnetic poles (N pole and S pole) in the circumferential direction are alternately magnetized, and it is a permanent magnet having four magnetic poles. In FIG. 1, the boundary line between the two different magnetized magnetic poles of the magnet 6 is indicated by a dotted line. The first teeth T1 to fifth teeth T5 as slots face the inner circumferential surface of the magnet 6.

[0015] FIG. 3 shows a schematic cross-sectional view of the portion where the commutator 4 and the plurality of brushes 7 are in contact in a plane perpendicular to the axial direction of the shaft 8. The plurality of brushes 7 have contact portions A and B that contact two adjacent segments among the plurality of segments (C1 to C10) in the circumferential direction. The contact portion A and the contact portion B are arranged at positions where the central angle θ centered on the axis of the shaft 8 is a predetermined angle (e.g., 90°) and are in contact with the commutator 4. The shaft 8 and the commutator 4 are adapted to rotate in the direction of arrow X.

[0016] As shown in FIGS. 2 and 3, in the circumferential direction (arrow X direction) of the commutator 4, when the width of the contact portions A and B of the plurality of brushes 7 with the commutator 4 is x, the width of the segments (C1 to C10) in the commutator 4 is y, and the gap between two adjacent segments is z, in this embodiment, the following relational expression (1) is satisfied. x < y + 2z ··· Relational expression (1)

[0017] By satisfying the above relational expression (1), the contact portions A and B of the brushes 7 will not come into contact with three or more segments at the same time, as shown in FIG. 3, and short circuits can be prevented.

[0018] In this embodiment, each of the coils 3 is wound across two of the multiple slots of the first tooth T1 to the fifth tooth T5. Furthermore, for each of the two slots (teeth) that the coil 3 straddles and is wound around, the winding direction of the coil 3 around one slot (teeth) is opposite to the winding direction of the coil 3 around the other slot (teeth).

[0019] Furthermore, in the circumferential direction, the coil 3 wound around one slot (tooth) is connected to one of the two adjacent segments, and the coil 3 wound around the other slot (tooth) is connected to the other of the two adjacent segments.

[0020] The winding direction of the coil 3 and the connection with the segments will be specifically described below using the coil 32 wound around two adjacent slots, the second tooth T2 and the third tooth T3, as a representative. In this embodiment, when indicating the winding direction of the coil 3 or the direction of current flow, the rotation direction on the drawing is conveniently used as "clockwise" or "counterclockwise." However, this merely indicates the rotation direction on the drawing and does not specify the actual winding direction of the coil or the direction of current flow. However, in the actual winding direction of the coil or the direction of current flow, "clockwise" and "counterclockwise" are opposite to each other. The same applies to the other embodiments below when indicating the winding direction of the coil 3 or the direction of current flow.

[0021] The coil 32 is wound across the adjacent second teeth T2 and third teeth T3. Furthermore, the winding direction of the coil 32 around the second tooth T2, which is one of the slots (in Figure 3, the winding of the coil 3 is "clockwise" when tracing the circumferential direction X between the contacting segments. Hereinafter, when the winding direction of the coil 3 is indicated as "clockwise" or "counterclockwise", this also applies to other embodiments that follow.) is opposite to the winding direction of the coil 32 around the third tooth T3, which is the other slot ("counterclockwise" in Figure 3).

[0022] Furthermore, in the circumferential direction, the coil 32 wound around the second tooth T2, which is the slot on one side, is connected to one of the two adjacent segments C3, C4, which is the segment C3 on one side, and the coil 32 wound around the third tooth T3, which is the slot on the other side, is connected to the other of the two adjacent segments C3, C4, which is the segment C4 on the other side.

[0023] In this embodiment, when focusing on each of the multiple slots (teeth), two coils 3 are wound around the slot (teeth), and the winding directions of the two wound coils 3 are opposite to each other. The winding direction of the coil 3 in each slot (tooth) will be specifically described below, taking the second tooth T2 as a representative example.

[0024] Two coils 3 are wound around the second tooth T2: a coil 32 connected to the segment C3 and a coil 31 connected to the segment C2. On the second tooth T2, the winding direction of the coil 32 (clockwise in FIG. 3) and the winding direction of the coil 31 (counterclockwise in FIG. 3) are opposite to each other.

[0025] 2, the coil 32 is wound clockwise around the second tooth T2 on the side connected to the segment C3, and then wound counterclockwise around the third tooth T3 and connected to the segment C4. On the other hand, the coil 31 is wound clockwise around the first tooth T1 on the side connected to the segment C1, and then wound counterclockwise around the second tooth T2 and connected to the segment C2.

[0026] The above explanation has been given using the second tooth T2 as a representative slot, but the state of the wound coil, the segment to which the coil is connected, and the relationship with the slots on one side and the other side are all the same for the other slots (first tooth T1, third to fifth teeth T3 to T5).

[0027] In this embodiment, the segments that are rotationally symmetrical in the circumferential direction (direction of arrow X) of the commutator 4 have the same potential. In Figure 2, taking segment C2 as an example, segments C2 and C7 are positioned in a rotationally symmetrical (more specifically, two-fold symmetrical) relationship in the circumferential direction (arrow X direction) of commutator 4, and are therefore at the same potential because they are connected by connecting wiring 9. The above-described relationship between the segments is also the same for other relationships between the segments C1 to C10 which are rotationally symmetric (two-fold symmetric) in the circumferential direction of the commutator 4 (direction of arrow X).

[0028] The operation of the motor 1 according to this embodiment will be described. 4 and 5 are explanatory diagrams for explaining, in time series, the change in magnetic poles of the slots and the movement of the components of the armature 10 when a predetermined current or voltage is applied to the motor 1 according to this embodiment. Similar to the schematic diagram of FIG. 2, (1) and (2) of FIG. 4 and (3) and (4) of FIG. 5 show the components of the armature 10 arranged in the circumferential direction, expanded in the left-right direction, and their relationships (positional relationships, connection relationships) with each other.

[0029] Figures 4 and 5 show how, over time, teeth T1 to T5, which are components of armature 10, move in the direction of arrow X, from (1) in Figure 4 to (4) in Figure 5, and the contact state (current-carrying state) between contact points A and B of multiple brushes 7 and segments C1 to C10 changes.

[0030] In order to make it easier to understand the positional relationship between the contact portions A and B of the brushes 7 and the teeth T1 to T5, etc., dashed lines are added as auxiliary lines to the right ends of the contact portions A and B across the time series in Figures 4 and 5. These auxiliary lines are also added in the explanatory diagrams for explaining the following embodiments in time series.

[0031] 4 and 5, coils 3 through which current flows are shown with solid lines and with arrows indicating the direction of the current flow. In contrast, coils 3 through which no current flows are shown with dashed lines. The selection of line types and arrows according to the state of current flow is the same in the explanatory diagrams of other embodiments below. Note that the connection wiring 9 is shown with solid lines in the wired state, regardless of the presence or absence or direction of current flow.

[0032] Figure 4 (1)~(2) and Fig. 5 ( 3 ) to (4), the magnet 6 and teeth T1 to T 5 The symbols between the and indicate the magnetic pole (north or south pole) of each tooth T1 to T5 in each state. In addition, areas where two N or S overlap (NN, SS) indicate a state where a stronger magnetic field is created compared to areas where there is only one (N, S). As will be described later, this indicates a slot where current flows in the same direction of rotation through two coils wound around one tooth. The areas marked with an x ​​indicate a state where no voltage is applied and no magnetic field is generated. The same symbols are used in the explanatory diagrams of the other embodiments below.

[0033] First, in the state of FIG. 2, a predetermined DC voltage is applied to the contact portions A and B of the plurality of brushes 7. FIG. 4(1) shows a state in which a predetermined DC voltage (in this embodiment, contact portion A is positive) is applied to contact portions A and B in the state of FIG. very , contact B is negative very 4(1), contact portions A of the brushes 7 are in contact with segment C3 of the commutator 4, and contact portions B are in contact with segments C5 and C6.

[0034] The applied voltage is applied to the first to fifth coils 31 to 35 via the respective connection wires 9 depending on the contact state between the multiple brushes 7 and the commutator 4, and a current flows with a selected positive or negative direction. Below, we will trace the flow of current starting from contact point A.

[0035] First, current flows from the positive contact A through the segment C3 to the coil 32. The current flows clockwise through the second tooth T2 and then through the third tooth T3. of The current flows counterclockwise and reaches segment C4. In this embodiment, when indicating the direction of rotation of the current flowing in each tooth, the direction of rotation of the current actually flowing in the coil is described, rather than tracing the coil in the direction of arrow X. This also applies to the following embodiments.

[0036] The current that flows into segment C4 travels along connecting wire 9 to segment C9, and then flows into coil 35. The current that flows into coil 35 again flows clockwise through fifth tooth T5, and then counterclockwise through first tooth T1, before reaching segment C10. The current flowing into the segment C10 travels through the connecting wire 9 to reach the segment C5, and then flows through the negative polarity contact wire 10, which is in contact with the segment C5. Department flows into B. As described above, the current flowing out from contact A, which is the positive pole, passes through various points and returns to contact B, which is the negative pole, thereby forming an electrical circuit.

[0037] Meanwhile, the current applied to contact A also flows into the lower connecting wire 9 in Fig. 4(1), travels along the connecting wire 9 to reach segment C8, and then flows into coil 34. The current that has flowed into coil 34 flows clockwise through fifth tooth T5, and then counterclockwise through fourth tooth T4, before reaching segment C7.

[0038] The current that flows into segment C7 travels along connecting wire 9 to reach segment C2, and then flows into coil 31. The current that flows into coil 31 again flows clockwise through second tooth T2, and then counterclockwise through first tooth T1, before reaching segment C1. The current flowing into the segment C1 then travels through the connecting wire 9 to reach the segment C6, and the negative polarity contact Department flows into B. As described above, the current flowing out from contact A, which is the positive pole, passes through various points and returns to contact B, which is the negative pole, thereby forming an electrical circuit.

[0039] However, since contact B is in contact with both segments C5 and C6, segments C5 and C6 are at the same potential. Therefore, no current flows through coil 33 connecting segments C5 and C6. In Figure 4(1), the coil 33 through which no current flows is shown by a dashed line.

[0040] Next, the magnetic poles of the magnetic fields generated in each of the teeth T1 to T5 in the state shown in Fig. 4(1) will be described. In this embodiment, when a current flows clockwise through the coil 3 wound around each of the teeth T1 to T5, the magnetic pole of the magnetic field generated becomes a north pole, and when a current flows counterclockwise, the magnetic pole of the magnetic field generated becomes a south pole.

[0041] In the first tooth T1, the currents flowing through the two wound coils 31, 35 are both counterclockwise. Therefore, when currents flow through the two coils 31, 35, the magnetic field generated has both S poles, and the S pole magnetic field is strengthened. Therefore, in Figure 4(1), a strong magnetic field SS is shown in the first tooth T1.

[0042] In the second tooth T2 and the fifth tooth T5, the currents flowing through the two wound coils 31, 32 and the two wound coils 34, 35 are both clockwise. Therefore, when currents flow through the two wound coils 31, 32 and the two wound coils 34, 35, the magnetic poles of the magnetic field generated are both north poles, and the north magnetic field is strengthened. Therefore, in FIG. 4(1), and 5th tooth T5 shows the NN of a strong magnetic field.

[0043] Of the two coils 32, 33 and two coils 33, 34 wound around the third tooth T3 and the fourth tooth T4, no current flows through the common coil 33, and the current that flows through the other coil 32, 34 is counterclockwise. Therefore, current flows through only one of the two coils 32, 33 and the two coils 33, 34, and the magnetic pole of the generated magnetic field is the S pole. Therefore, in Figure 4(1), a single S is shown for the third tooth T3 and the fourth tooth T4.

[0044] To summarize the above, as shown in Figure 4(1), the magnetic poles of teeth T1 to T5 are SS, NN, S, S, NN, in that order (hereinafter, this will be abbreviated as "the magnetic poles of teeth T1 to T5 are SS·NN·S·S·NN").

[0045] Due to the interaction of attractive or repulsive forces between the magnetic poles of these teeth T1 to T5 and the magnetic poles of the magnet 6, the teeth (slots) T1 to T5, the first to fifth coils 31 to 35, and the segments C1 to C10 (hereinafter sometimes referred to as "commutator 4, etc."), which are components of the armature 10, move in the direction of arrow X, causing the shaft 8 to rotate.

[0046] In addition, the state of current flow and the state of magnetic field generation in each tooth T1 to T5 can be easily understood in other states from Fig. 4(2) onwards by following the contact state between the segments C1 to C5 and the contact parts A and B of the brushes 7 and the connection state of the coil 3, connecting wiring 9, etc. in the drawings, just as in the state of Fig. 4(1). Therefore, detailed explanations of each figure in other states from Fig. 4(2) onwards will be omitted. This also applies to the explanatory diagrams of other embodiments that follow.

[0047] When the commutator 4 and other components move to the state shown in Figure 4(2), contact portion A of one brush 7 comes into contact with segments C2 and C3, while contact portion B of the other brush 7 remains in contact with segments C5 and C6.

[0048] The change in the contact state between the multiple brushes 7 and the commutator 4 also changes the state of the current in the first to fifth coils 31 to 35 (whether the current flows or not, and if it does flow, the direction of the current; hereinafter, this also applies to "current state"). As a result, as shown in Figure 4(2), the magnetic poles of teeth T1 to T3 and T5 are SS, NN, S, N, respectively, and tooth T4 is in a state where no current flows and no magnetic field is generated (marked x) (hereinafter, this will be abbreviated as "the magnetic poles of teeth T1 to T5 are SS NN S x N"). The magnetic poles of the teeth T1 to T5 and the magnetic poles of the magnet 6 interact with each other due to attractive or repulsive forces, causing the commutator 4 and other components to move in the direction of arrow X, thereby maintaining the rotation of the shaft 8.

[0049] Furthermore, the commutator 4 and other components move to the state shown in Figure 5(3), but the contact state between the contact portions A and B of the multiple brushes 7 and the commutator 4 is the same as in the state shown in Figure 4(2). That is, the magnetic poles of the teeth T1 to T5 are SS·NN·S·×·N. Therefore, in the state shown in Figure 5(3), as in the state shown in Figure 4(2), the commutator 4 and other components move in the direction of arrow X due to the interaction caused by the attractive or repulsive forces between the magnetic poles of the teeth T1 to T5 and the magnetic poles of the magnet 6, and the rotation of the shaft 8 is maintained.

[0050] Next, when the commutator 4 and other components move to the state shown in Figure 5(4), contact portion A of one brush 7 remains in contact with segments C2 and C3, while contact portion B of the other brush 7 is in contact only with segment C5. This change in contact state between the multiple brushes 7 and the commutator 4 also changes the state of the current flowing through the first to fifth coils 31-35, and the magnetic poles of the teeth T1-T5 become SS-NN-SS-N-N, as shown in Figure 5(4). The magnetic poles of the teeth T1 to T5 and the magnetic poles of the magnet 6 interact with each other due to attractive or repulsive forces, causing the commutator 4 and other components to move in the direction of arrow X, thereby maintaining the rotation of the shaft 8.

[0051] In the motor 1 of this embodiment, a predetermined current or voltage is applied to the plurality of brushes 7, and the above-mentioned (1)~(2) and Fig. 5 ( 3 As shown in the time series of (1) to (4), the rotation of the commutator 4 and the like in the direction of the arrow X is maintained, and by continuing this, the rotation of the motor continues.

[0052] In the motor 1 of this embodiment, the coil is wound around one of two slots (teeth) across which the coil straddles, and the direction in which the coil is wound around one slot (teeth) is opposite to the direction in which the coil is wound around the other slot (teeth). This reduces the potential difference between adjacent segments that switch between contact and separation with the brush contact surface.

[0053] For example, in the state shown in Figure 4(1), contact point A with the commutator 4 is in contact with segment C3, and when the commutator 4 and other components move to the state shown in Figure 4(2) due to the rotation of the motor 1, contact point A comes into contact with segment C2 while maintaining contact with segment C3. At this time, if the potential difference between segments C3 and C2 is relatively large, sparks are likely to occur.

[0054] However, in the state shown in FIG. 4(1), segment C2 before contact with contact portion A is in a state in which current flows toward the coils (32, 31), similar to segment C3 in contact with contact portion A. That is, since the direction of the current toward the coils (32, 31) (or the electrodes) is the same for segments C2 and C3, the potential difference between segments C2 and C3 is small. Therefore, even when transitioning to the state shown in FIG. 4(2) in which contact portion A maintains contact with segment C3 and also makes contact with segment C2, spark generation is suppressed.

[0055] On the other hand, if two coils are wound in overlapping fashion on each slot (tooth), and the currents flowing in the two coils are in opposite directions, the magnetic fields generated by each coil will be in opposite directions and will cancel each other out. If the magnetic fields cancel each other out in slot 1 (tooth), the magnetic flux will not act effectively, which can result in reduced motor efficiency or even a failure to rotate.

[0056] In the motor 1 of this embodiment, of the two slots across which the coil is wound, the winding direction of the coil around one slot (tooth) is opposite to the winding direction of the coil around the other slot (tooth). Also, the winding directions of the two coils wound around each slot (tooth) are opposite to each other.

[0057] Therefore, when current is applied from each segment, the current flows in the two coils lap-wound around each slot (tooth) in the same direction, or no current flows in one or two coils. In other words, with motor 1 of this embodiment, the current flows in the two coils lap-wound around each slot (tooth) in the opposite directions, preventing a decrease in motor efficiency.

[0058] Furthermore, because the motor 1 of this embodiment is a four-pole motor, high-frequency noise is reduced. In a brush motor, if the number of poles is too large (for example, eight or more poles), the period of the torque ripple becomes shorter, and high-frequency noise due to the torque ripple may occur. However, in this embodiment, by reducing the number of poles, high-frequency noise can be suppressed.

[0059] (Second embodiment) A motor according to a second embodiment of the present invention will be described. The motor according to the second embodiment differs from the motor 1 according to the first embodiment in the configuration of the brushes. Specifically, the brushes 7′ in this embodiment are wider than the brushes 7 in the first embodiment.

[0060] Although the shape of the brush is different, the other configurations are the same as those of the first embodiment, so for the overall configuration of the motor of this embodiment, please refer to Figures 1 and 3 which show the motor 1 of the first embodiment. However, the "brush 7" should be interpreted as being replaced with the wider "brush 7'."

[0061] 6 is a schematic diagram showing the mutual relationships (positional relationships, connection relationships) of the components of the armature arranged in the circumferential direction in a motor according to a second embodiment of the present invention, with the components expanded in the left-right direction. In this embodiment, the same reference numerals are used for the same components as in the first embodiment.

[0062] As shown in Figures 3 and 6, in the circumferential direction of the commutator 4 (direction of arrow X), when the width of contact portions A and B of the multiple brushes 7' with the commutator 4 is x, the width of the segments (C1 to C10) in the commutator 4 is y, and the gap between two adjacent segments is z, in this embodiment, the following relational expression (2) is satisfied. 2y+3z>x>y+2z ··· Relational expression (2)

[0063] By satisfying the above relational expression (2), the contact points A and B of the multiple brushes 7' always come into contact with two or more adjacent segments (x>y+2z), and never come into contact with four or more segments simultaneously (2y+3z>x), thereby preventing short circuits.

[0064] Regarding the operation of the motor according to this embodiment, the same explanatory diagrams as those in Figures 4 and 5 in the first embodiment are presented in Figures 7 and 8 in this embodiment, and detailed explanations thereof will be omitted. 7 and 8 are explanatory diagrams for explaining, in time series, the change in magnetic poles of the slots and the movement of the components of the armature 10 when a predetermined current or voltage is applied to the motor according to this embodiment. As with the schematic diagram of FIG. 6, (1) to (2) of FIG. 7 and (3) to (4) of FIG. 8 show the components of the armature 10 arranged in the circumferential direction, expanded in the left-right direction, and their relationships (positional relationships, connection relationships) with each other.

[0065] 7 and 8, the teeth T1 to T5, which are components of the armature 10, move in the direction of the arrow X from (1) in FIG. 7 to (4) in FIG. 8 over time, and a plurality of brushes 7′ 10 shows how the contact state (energized state) between contact portions A, B and segments C1 to C10 changes.

[0066] In the motor of this embodiment, as in the first embodiment, a plurality of brushes are used. 7′ 7(1)-(2) and 8(3)-(4), currents of selected positive or negative directions flow through the first to fifth coils 31-35 via the respective connecting wires in accordance with changes in the contact state between the commutator 4 and the teeth T1-T5. As a result, as shown in each of Figs. 7(1)-(2) and Fig. 8(3)-(4), the teeth T1-T5 each exhibit a magnetic pole, and due to the interaction of the magnetic poles of the teeth T1-T5 and the magnetic pole of the magnet 6 caused by attractive or repulsive forces, the commutator 4 and the like move in the direction of arrow X, and the rotation of the shaft 8 is maintained.

[0067] In the motor of this embodiment, a plurality of brushes7′ By applying a predetermined current or voltage to the (1)~(2) and Fig. 8 ( 3 As shown in the time series of (1) to (4), the rotation of the commutator 4 and the like in the direction of the arrow X is maintained, and by continuing this, the rotation of the motor continues.

[0068] In the motor of this embodiment, the coil is wound around one of two slots (teeth) across which the coil straddles, and the direction in which the coil is wound around one slot (teeth) is opposite to the direction in which the coil is wound around the other slot (teeth). This reduces the potential difference between adjacent segments that switch between contact and separation with the brush contact surface.

[0069] For example, in the state shown in FIG. 8(3), the contact portion B with the commutator 4 is in contact with the segments C5 and C6. Ta's When the commutator 4 and other components move to the state shown in Figure 8(4) due to rotation, contact B contacts segment C4 while maintaining contact with segments C5 and C6. At this time, if the potential difference between segments C5 and C4 is relatively large, sparks are likely to occur.

[0070] However, in the state of Fig. 8(3), contact B is in contact with both segments C5 and C6, so segments C5 and C6 are at the same potential and no current flows between them. Therefore, even if contact B maintains contact with segments C5 and C6 and transitions to the state of Fig. 8(4) where it contacts segment C4, no potential difference is generated that would cause the current to flow in the opposite direction, and sparks are suppressed.

[0071] On the other hand, in the motor of this embodiment, of the two slots across which the coil is wound, the winding direction of the coil around one slot (teeth) is opposite to the winding direction of the coil around the other slot (teeth).Furthermore, the winding directions of the two coils wound around each slot (teeth) are opposite to each other.

[0072] Therefore, when current is applied from each segment, the current flows in the two coils lap-wound around each slot (tooth) in the same direction, or no current flows in one or two coils. In other words, with the motor of this embodiment, the current flows in the two coils lap-wound around each slot (tooth) in the opposite directions, preventing a decrease in motor efficiency.

[0073] Furthermore, because the motor of this embodiment is a four-pole motor, high-frequency noise is reduced. In brush motors, if the number of poles is too high (for example, eight or more), the period of torque ripple becomes shorter, which can cause high-frequency noise due to the torque ripple. However, in this embodiment, by reducing the number of poles, high-frequency noise can be suppressed.

[0074] (Third embodiment) A motor according to a third embodiment of the present invention will be described. The motor according to the third embodiment differs from the motor 1 according to the first embodiment in the configuration of the armature. Specifically, in this embodiment, the rotor core 2 has seven slots and the commutator 4 has 14 segments.

[0075] Although the shape of the armature is slightly different, the magnet remains cylindrical in appearance and other configurations are the same as those of the first embodiment, so for the overall configuration of the motor of this embodiment, please refer to Figures 1 and 3 which show the motor 1 of the first embodiment. Note that the same reference numerals as in the first embodiment are used, and new reference numerals are assigned to the excess numbers for the teeth, coils, and segments that are present in greater numbers.

[0076] FIG. 9 is a schematic diagram showing the mutual relationships (positional relationships, connection relationships) of the components of the armature arranged in the circumferential direction in a motor according to a third embodiment, which is one example of the present invention, with the components being expanded in the left-right direction.

[0077] 9, the rotor core 2 has first teeth T1 to seventh teeth T7 as a plurality of (seven in this embodiment) slots arranged in the circumferential direction. Coils 31 to 37 are wound around the first teeth T1 to seventh teeth T7, respectively. The winding directions (spiral directions) of the coils 31 to 37 will be described later.

[0078] The commutator 4 has a plurality of segments C1 to C14 arranged in the circumferential direction. The segments C1 to C14 are in contact with contact portions A and B of the plurality of brushes 7 to conduct electricity.

[0079] In this embodiment, the contact portions A and B of the plurality of brushes 7 and the segments (C1 to C 14 The relationship between the magnitude of and satisfies the above-mentioned relational expression (1). By satisfying the relational expression (1), the contact portions A and B of the multiple brushes 7 do not come into contact with three or more segments at the same time, as shown in FIG. 9, thereby preventing short circuits.

[0080] In this embodiment, each of the coils 3 is wound across two of the multiple slots of the first tooth T1 to the seventh tooth T7. Furthermore, for each of the two slots (teeth) that the coil 3 straddles and is wound around, the winding direction of the coil 3 around one slot (teeth) is opposite to the winding direction of the coil 3 around the other slot (teeth).

[0081] Furthermore, in the circumferential direction, the coil 3 wound around one slot (tooth) is connected to one of the two adjacent segments, and the coil 3 wound around the other slot (tooth) is connected to the other of the two adjacent segments.

[0082] The winding direction of the coil 3 and the connection with the segments will be specifically described below using the coil 32 wound across two slots, the second tooth T2 and the fourth tooth T4, as a representative example. In this embodiment, between the second tooth T2 and the fourth tooth T4, which are two slots across which the coil 32 is wound, there is a third tooth T3, which is a slot different from the two slots.

[0083] The winding direction of the coil 32 around one slot, the second tooth T2 (clockwise in Figure 9) is opposite to the winding direction of the coil 32 around the other slot, the fourth tooth T4 (counterclockwise in Figure 9).

[0084] Furthermore, in the circumferential direction, the coil 32 wound around the second tooth T2, which is the slot on one side, is connected to one of the two adjacent segments C3, C4, which is the segment C3 on one side, and the coil 32 wound around the fourth tooth T4, which is the slot on the other side, is connected to the other of the two adjacent segments C3, C4, which is the segment C4 on the other side.

[0085] In this embodiment, when focusing on each of the multiple slots (teeth), two coils 3 are wound around the slot (teeth), and the winding directions of the two wound coils 3 are opposite to each other. The winding direction of the coil 3 in each slot (tooth) will be specifically described below, taking the fourth tooth T4 as a representative example.

[0086] Two coils 3 are wound around the fourth tooth T4: a coil 34 connected to the segment C7 and a coil 32 connected to the segment C4. On the fourth tooth T4, the winding direction of the coil 34 (clockwise in FIG. 9) and the winding direction of the coil 32 (counterclockwise in FIG. 9) are opposite to each other.

[0087] 9, the coil 34 is wound clockwise around the fourth tooth T4 on the side connected to the segment C7, and then wound counterclockwise around the sixth tooth T6 and connected to the segment C8. On the other hand, the coil 32 is wound clockwise around the second tooth T2 on the side connected to the segment C3, and then wound counterclockwise around the fourth tooth T4 and connected to the segment C4.

[0088] The above explanation has been given using the fourth tooth T4 as a representative slot, but the state of the wound coil, the segment to which the coil is connected, and the relationship with the slots on one side and the other side are all the same for the other slots (the first to third teeth T1 to T3, and the fifth to seventh teeth T5 to T7).

[0089] In this embodiment, the segments that are rotationally symmetrical in the circumferential direction (direction of arrow X) of the commutator 4 have the same potential. In Figure 9, taking segment C2 as an example, segment C2 and segment C9 are positioned in a rotationally symmetrical (more specifically, two-fold symmetrical) relationship in the circumferential direction (arrow X direction) of commutator 4, and are connected by connecting wiring 9, so they are at the same potential. The above-described relationship between the segments is also true for other relationships between the segments C1 to C14 which are rotationally symmetric (two-fold symmetric) in the circumferential direction of the commutator 4 (direction of arrow X).

[0090] Regarding the operation of the motor according to this embodiment, the same explanatory diagrams as those in Figures 4 and 5 in the first embodiment are presented in Figures 10 and 11 in this embodiment, and detailed explanations thereof will be omitted. 10 and 11 are explanatory diagrams for explaining, in time series, the change in magnetic poles of the slots and the movement of the components of the armature 10 when a predetermined current or voltage is applied to the motor according to this embodiment. As with the schematic diagram of FIG. 9, (1) to (3) of FIG. 10 and (4) to (5) of FIG. 11 show the components of the armature 10 arranged in the circumferential direction, expanded in the left-right direction, and show their mutual relationships (positional relationships, connection relationships).

[0091] Figures 10 and 11 show how, over time, teeth T1 to T7, which are components of armature 10, move in the direction of arrow X, from (1) in Figure 10 to (5) in Figure 11, and the contact state (current-carrying state) between contact points A and B of multiple brushes 7 and segments C1 to C14 changes.

[0092] In the motor of this embodiment, as in the first embodiment, currents of selected positive or negative directions flow through the first to seventh coils 31 to 37 via the respective connecting wires in response to changes in the contact state between the multiple brushes 7 and the commutator 4. As a result, as shown in each of Figs. 10(1) to (3) and Fig. 11(4) to (5), the teeth T1 to T7 each exhibit a magnetic pole, and due to the interaction of attractive or repulsive forces between the magnetic poles of the teeth T1 to T7 and the magnetic pole of the magnet 6, the commutator 4 and the like move in the direction of arrow X, thereby maintaining the rotation of the shaft 8.

[0093] In the motor of this embodiment, a predetermined current or voltage is applied to the plurality of brushes 7, and the above-mentioned (1) to (3) and Fig. 11 ( 4As shown in the time series of (1) to (5), the rotation of the commutator 4 and the like in the direction of the arrow X is maintained, and by continuing this, the rotation of the motor continues.

[0094] In the motor of this embodiment, the coil is wound around one of two slots (teeth) across which the coil straddles, and the direction in which the coil is wound around one slot (teeth) is opposite to the direction in which the coil is wound around the other slot (teeth). This reduces the potential difference between adjacent segments that switch between contact and separation with the brush contact surface.

[0095] For example, in the state shown in Figure 10(1), contact point A with the commutator 4 is in contact with segment C3, and when the motor rotates and the commutator 4 and other components move to the state shown in Figure 10(2), contact point A comes into contact with segment C2 while maintaining contact with segment C3. At this time, if the potential difference between segments C3 and C2 is relatively large, sparks are likely to occur.

[0096] However, in the state shown in Figure 10(1), segment C2 before contact with contact portion A is in a state in which current flows toward the coils (32, 31), just like segment C3 with which contact portion A is in contact. That is, since the direction of the current (or the electrode) toward the coils (32, 31) is the same for segments C2 and C3, the potential difference between segments C2 and C3 is small. Therefore, even when transitioning to the state shown in Figure 10(2) in which contact portion A maintains contact with segment C3 and also comes into contact with segment C2, spark generation is suppressed.

[0097] On the other hand, in the motor of this embodiment, of the two slots across which the coil is wound, the winding direction of the coil around one slot (teeth) is opposite to the winding direction of the coil around the other slot (teeth).Furthermore, the winding directions of the two coils wound around each slot (teeth) are opposite to each other.

[0098] Therefore, when current is applied from each segment, the current flows in the two coils lap-wound around each slot (tooth) in the same direction, or no current flows in one or two coils. In other words, with the motor of this embodiment, the current flows in the two coils lap-wound around each slot (tooth) in the opposite directions, preventing a decrease in motor efficiency.

[0099] Furthermore, because the motor of this embodiment is a four-pole motor, high-frequency noise is reduced. In brush motors, if the number of poles is too high (for example, eight or more), the period of torque ripple becomes shorter, which can cause high-frequency noise due to the torque ripple. However, in this embodiment, by reducing the number of poles, high-frequency noise can be suppressed.

[0100] (Fourth embodiment) A motor according to a fourth embodiment of the present invention will be described. The motor according to the fourth embodiment differs from the motor 1 according to the first embodiment in the configuration of the armature. Specifically, in this embodiment, the rotor core 2 has 9 slots and the commutator 4 has 18 segments.

[0101] Although the shape of the armature is slightly different, the magnet remains cylindrical in appearance and other configurations are the same as those of the first embodiment, so for the overall configuration of the motor of this embodiment, please refer to Figures 1 and 3 which show the motor 1 of the first embodiment. Note that the same reference numerals as in the first embodiment are used, and new reference numerals are assigned to the excess numbers for the teeth, coils, and segments that are present in greater numbers.

[0102] FIG. 12 is a schematic diagram showing the mutual relationships (positional relationships, connection relationships) of the components of the armature arranged in the circumferential direction in a motor according to a fourth embodiment, which is one example of the present invention, with the components expanded in the left-right direction.

[0103] 12, the rotor core 2 has first teeth T1 to ninth teeth T9 as a plurality of (nine in this embodiment) slots arranged in the circumferential direction. Coils 31 to 39 are wound around the first teeth T1 to ninth teeth T9, respectively. The winding directions (spiral directions) of the coils 31 to 39 will be described later.

[0104] The commutator 4 has a plurality of segments C1 to C18 arranged in the circumferential direction. The segments C1 to C18 come into contact with contact portions A and B of the plurality of brushes 7 to conduct electricity.

[0105] In this embodiment, the relationship between the size of the contact portions A and B of the brushes 7 and the size of the segments (C1 to C18) of the commutator 4 satisfies the above-mentioned relational expression (1). By satisfying the relational expression (1), the contact portions A and B of the brushes 7 are 12 As shown in Fig. 1, since three or more segments are not in contact at the same time, short circuits can be prevented.

[0106] In this embodiment, each of the coils 3 is wound across two of the multiple slots of the first tooth T1 to the ninth tooth T9. Furthermore, for each of the two slots (teeth) that the coil 3 straddles and is wound around, the winding direction of the coil 3 around one slot (teeth) is opposite to the winding direction of the coil 3 around the other slot (teeth).

[0107] Furthermore, in the circumferential direction, the coil 3 wound around one slot (tooth) is connected to one of the two adjacent segments, and the coil 3 wound around the other slot (tooth) is connected to the other of the two adjacent segments.

[0108] The winding direction of the coil 3 and the connection with the segments will be specifically described below using the coil 32 wound across two slots, the second tooth T2 and the fourth tooth T4, as a representative example. In this embodiment, between the second tooth T2 and the fourth tooth T4, which are two slots across which the coil 32 is wound, there is a third tooth T3, which is a slot different from the two slots.

[0109] The winding direction of the coil 32 around one slot, the second tooth T2 (clockwise in Figure 12) is opposite to the winding direction of the coil 32 around the other slot, the fourth tooth T4 (counterclockwise in Figure 12).

[0110] Furthermore, in the circumferential direction, the coil 32 wound around the second tooth T2, which is the slot on one side, is connected to one of the two adjacent segments C3, C4, which is the segment C3 on one side, and the coil 32 wound around the fourth tooth T4, which is the slot on the other side, is connected to the other of the two adjacent segments C3, C4, which is the segment C4 on the other side.

[0111] In this embodiment, when focusing on each of the multiple slots (teeth), two coils 3 are wound around the slot (teeth), and the winding directions of the two wound coils 3 are opposite to each other. The winding direction of the coil 3 in each slot (tooth) will be specifically described below, taking the fourth tooth T4 as a representative example.

[0112] Two coils 3 are wound around the fourth tooth T4: a coil 34 connected to the segment C7 and a coil 32 connected to the segment C4. On the fourth tooth T4, the winding direction of the coil 34 (clockwise in FIG. 12) and the winding direction of the coil 32 (counterclockwise in FIG. 12) are opposite to each other.

[0113] 12, the coil 34 is wound clockwise around the fourth tooth T4 on the side connected to the segment C7, and then wound counterclockwise around the sixth tooth T6 and connected to the segment C8. On the other hand, the coil 32 is wound clockwise around the second tooth T2 on the side connected to the segment C3, and then wound counterclockwise around the fourth tooth T4 and connected to the segment C4.

[0114] The above explanation has been given using the fourth tooth T4 as a representative slot, but the state of the wound coil, the segment to which the coil is connected, and the relationship with the slots on one side and the other side are all the same for the other slots (the first to third teeth T1 to T3, and the fifth to ninth teeth T5 to T9).

[0115] In this embodiment, the segments that are rotationally symmetrical in the circumferential direction (direction of arrow X) of the commutator 4 have the same potential. In Figure 12, taking segment C2 as an example, segment C2 and segment C11 are positioned in a rotationally symmetric (more specifically, two-fold symmetric) relationship in the circumferential direction (arrow X direction) of commutator 4, and are therefore at the same potential because they are connected by connecting wiring 9. The above-described relationship between the segments is also true for other relationships between the segments C1 to C18 which are rotationally symmetric (two-fold symmetric) in the circumferential direction of the commutator 4 (direction of arrow X).

[0116] Regarding the operation of the motor in this embodiment, detailed explanation will be omitted by presenting explanatory diagrams similar to those in Figures 4 and 5 in the first embodiment as Figures 13 and 14 in this embodiment as well. 13 and 14 are explanatory diagrams for explaining, in time series, the change in magnetic poles of the slots and the movement of the components of the armature 10 when a predetermined current or voltage is applied to the motor according to this embodiment. As with the schematic diagram of FIG. 12, (1) and (2) of FIG. 13 and (3) and (4) of FIG. 14 show the components of the armature 10 arranged in the circumferential direction, expanded in the left-right direction, and their relationships (positional relationships, connection relationships) with each other.

[0117] Figures 13 and 14 show how, over time, teeth T1 to T9, which are components of armature 10, move in the direction of arrow X, from (1) in Figure 13 to (4) in Figure 14, and the contact state (current-carrying state) between contact points A and B of multiple brushes 7 and segments C1 to C18 changes.

[0118] In the motor of this embodiment, as in the first embodiment, currents of selected positive or negative directions flow through the first to ninth coils 31 to 39 via the respective connecting wires in response to changes in the contact state between the multiple brushes 7 and the commutator 4. As a result, as shown in each of Figs. 13(1) and (2) and Fig. 14(3) and (4), the teeth T1 to T9 each exhibit a magnetic pole, and the magnetic poles of the teeth T1 to T9 interact with the magnetic pole of the magnet 6 due to attractive or repulsive forces, causing the commutator 4 and other components to move in the direction of arrow X, thereby maintaining the rotation of the shaft 8.

[0119] In the motor of this embodiment, a predetermined current or voltage is applied to the plurality of brushes 7, thereby achieving the above-described (1)~(2) and Fig. 14 ( 3 As shown in the time series of (1) to (4), the rotation of the commutator 4 and the like in the direction of the arrow X is maintained, and by continuing this, the rotation of the motor continues.

[0120] In the motor of this embodiment, the coil is wound around one of two slots (teeth) across which the coil straddles, and the direction in which the coil is wound around one slot (teeth) is opposite to the direction in which the coil is wound around the other slot (teeth). This reduces the potential difference between adjacent segments that switch between contact and separation with the brush contact surface.

[0121] For example, in the state shown in Figure 13(1), contact point A with the commutator 4 is in contact with segment C3, and when the motor rotates and the commutator 4 and other components move to the state shown in Figure 13(2), contact point A comes into contact with segment C2 while maintaining contact with segment C3. At this time, if the potential difference between segments C3 and C2 is relatively large, sparks are likely to occur.

[0122] However, in the state shown in Figure 13(1), segment C2 before contact with contact portion A is in a state in which current flows toward the coils (32, 31), just like segment C3 with which contact portion A is in contact. That is, since the direction of the current (or the electrode) toward the coils (32, 31) is the same for segments C2 and C3, the potential difference between segments C2 and C3 is small. Therefore, even when transitioning to the state shown in Figure 13(2) in which contact portion A maintains contact with segment C3 and also makes contact with segment C2, spark generation is suppressed.

[0123] On the other hand, in the motor of this embodiment, of the two slots across which the coil is wound, the winding direction of the coil around one slot (teeth) is opposite to the winding direction of the coil around the other slot (teeth).Furthermore, the winding directions of the two coils wound around each slot (teeth) are opposite to each other.

[0124] Therefore, when current is applied from each segment, the current flows in the two coils lap-wound around each slot (tooth) in the same direction, or no current flows in one or two coils. In other words, with the motor of this embodiment, the current flows in the two coils lap-wound around each slot (tooth) in the opposite directions, preventing a decrease in motor efficiency.

[0125] Furthermore, because the motor of this embodiment is a four-pole motor, high-frequency noise is reduced. In brush motors, if the number of poles is too high (for example, eight or more), the period of torque ripple becomes shorter, which can cause high-frequency noise due to the torque ripple. However, in this embodiment, by reducing the number of poles, high-frequency noise can be suppressed.

[0126] (Fifth embodiment) A motor according to a fifth embodiment of the present invention will be described below. The motor according to the fifth embodiment differs from the motor 1 according to the first embodiment in the configuration of the brushes and coils.

[0127] More specifically, the brush 7" in this embodiment is narrower than the brush 7 in the first embodiment, and the contact portion of the brush 7" is disposed at a different position in the circumferential direction. In addition, the connection of the coil 3 to the segments C1 to C10 is also shifted in the circumferential direction compared to the first embodiment.

[0128] Although the shape and arrangement of the brushes are different, the other configurations are the same as those of the first embodiment, so for the overall configuration of the motor of this embodiment, please refer to Figures 1 and 3 which show the motor 1 of the first embodiment. However, the "brush 7" will be interpreted as being replaced with a narrower "brush 7" and with a different arrangement.

[0129] FIG. 15 is a schematic diagram showing each component of the armature arranged in the circumferential direction developed in the left-right direction and their mutual relationships (positional relationship, connection relationship) in a motor according to a fifth embodiment which is an example of the present invention. In the present embodiment, the same reference numerals are used for the same components as in the first embodiment.

[0130] Replace "brush 7" in FIG. 3 with "brush 7″" in FIG. 15. When the widths of the contact portions A and B between the plurality of brushes 7″ and the commutator 4 in the circumferential direction (arrow X direction) of the commutator 4 are x, the width of the segments (C1 to C10) in the commutator 4 is y, and the gap between two adjacent segments is z, in the present embodiment, the brush 7″ satisfies the following relational expression (1) as in the first embodiment. x < y + 2z ··· Relational expression (1)

[0131] By satisfying the above relational expression (1), the contact portions A and B of the plurality of brushes 7″ 15 as shown in the figure, will not contact three or more segments simultaneously, so that short circuits can be suppressed.

[0132] In the present embodiment, similar to the first embodiment, the magnets 6 have two different magnetic poles (S pole and N pole) arranged alternately in the circumferential direction. In the circumferential direction, the contact surfaces of the commutator 4 that contact the contact portions A and B of the brush 7″ can be regarded as having regions corresponding to two different magnetic poles of the magnet 6 respectively.

[0133] That is, as shown in FIG. 15, the contact surface of the commutator 4 (the surface connecting the segments C1 to C10 and the gaps between each segment; in FIG. 15, it is a straight line including the undersides of the segments C1 to C10, but in reality it is the cylindrical outer surface of the commutator 4) can be seen as having regions N1, S1, N2, and S2 in the circumferential direction, which correspond to the two different magnetic poles of the magnet 6. Note that in FIG. 15, the contact surface of the commutator 4, including parts of the segments C1 and C2 protruding to the left from region N1, actually corresponds to region S2 on the right.

[0134] The contact portion A of the brush 7" is in contact with the commutator 4 across the area N1 and the area S1. The contact portion B of the brush 7" is in contact with the commutator 4 across the area S1 and the area N 2 In contrast to this, in the first embodiment, contact portion A of brush 7 contacts commutator 4 at the center of the region corresponding to region N1, and contact portion B contacts commutator 4 at the center of the region corresponding to region S1, which is different from the present embodiment.

[0135] In this embodiment, too, when focusing on each of the multiple slots (teeth), two coils 3 are wound around that slot (teeth), and the winding directions of the two wound coils 3 are opposite to each other. The winding direction of the coil 3 in each slot (tooth) will be specifically described below, taking the second tooth T2 as a representative example.

[0136] Two coils 3 are wound around the second tooth T2: a coil 33 connected to segment C4 and a coil 32 connected to segment C3. On the second tooth T2, the winding direction of the coil 33 (clockwise in FIG. 15) and the winding direction of the coil 32 (counterclockwise in FIG. 15) are opposite to each other.

[0137] 15, the coil 33 is wound clockwise around the second tooth T2 on the side connected to segment C4, and then wound counterclockwise around the third tooth T3 and connected to segment C5. On the other hand, the coil 32 is wound clockwise around the first tooth T1 on the side connected to segment C2, and then wound counterclockwise around the second tooth T2 and connected to segment C3.

[0138] The above explanation has been given using the second tooth T2 as a representative slot, but the state of the wound coil, the segment to which the coil is connected, and the relationship with the slots on one side and the other side are all the same for the other slots (first tooth T1, third to fifth teeth T3 to T5).

[0139] FIG. 16 is a schematic diagram showing only the state of current flow when a predetermined current or voltage is applied to the motor of this embodiment. In FIG. 16, the magnet 6 and multiple brushes 7" are fixed members, and the teeth T1 to T5 around which the coil 3 is wound, which serves as an armature, and the connecting wires 9 move in the direction of arrow X relative to these members.

[0140] In the state shown in FIG. 16, contact portions A of the multiple brushes 7" are in contact with segments C4 and C5 of the commutator 4, and contact portion B is in contact with segment C7. In this state, as shown in FIG. 16, current flows through each coil and connecting wiring 9 in the direction of the arrows, and no current flows in the areas indicated by the dashed lines. As a result, in the state shown in FIG. 16, the magnetic poles of the teeth T1 to T5 are SS·N·N·SS·NN. The magnetic poles of the teeth T1 to T5 and the magnetic poles of the magnet 6 interact with each other due to attractive or repulsive forces, causing the commutator 4 and other components to move in the direction of arrow X, and causing the shaft 8 to rotate.

[0141] In this embodiment, the brush 7" has a narrower width and the position of the contact portion of the brush 7" is different (shifted), and the configuration is the same as that of the first embodiment, and the wiring (connection) of the coil 3 and the connection wiring 9 is also the same. The motor of this embodiment isIt drives in the same way as the motor 1 of the first embodiment and has the same functions as the motor 1. Therefore, a detailed description of this embodiment will be omitted (please refer to the description of the first embodiment). However, the configuration of this embodiment is not the same as the first embodiment in terms of motor efficiency, functions, etc., and in some cases it may have higher motor efficiency or other superior functions.

[0142] (Sixth embodiment) A motor according to a sixth embodiment of the present invention will be described. The motor according to the sixth embodiment differs from the motor 1 according to the first embodiment in the configuration of the coil. More specifically, the present embodiment differs from the first embodiment in the manner in which the coil is wound.

[0143] Although the coil winding is slightly different in this way, the other configurations are the same as those of the fifth embodiment, and therefore the overall configuration of the motor of this embodiment can be considered as the same as that of the motor of the fifth embodiment. Ta 15 and 16. Note that the same reference numerals as those in the fifth embodiment are used.

[0144] In this embodiment, focusing on each of the multiple slots (teeth), two coils 3 are wound around the slot (teeth), and the winding directions of the two wound coils 3 are opposite to each other. Furthermore, the number of turns of one of the two wound coils 3 is different from the number of turns of the other coil. Specifically, one coil is wound on top of the other coil, and the number of turns of the other coil is greater than the number of turns of the first coil (FIGS. 17 and 18).

[0145] 17, the other coil, coil 33, is wound twice around the second tooth T2, and the one coil, coil 32, is wound once, but this is merely a schematic illustration of the difference in the number of turns of the one coil, coil 32, around the second tooth T2 compared to the other coil, coil 33, and does not reflect the actual number of turns. For example, the other coil, coil 33, may be wound 27 times around the second tooth T2, and the one coil, coil 32, may be wound 25 times, or may have other numbers of turns.

[0146] The above explanation has been given using the second tooth T2 as a representative slot, but the state of the wound coil, the segment to which the coil is connected, and the relationship with the slots on one side and the other side are all the same for the other slots (first tooth T1, third to fifth teeth T3 to T5).

[0147] In the motor of this embodiment, two coils are wound around each of the multiple slots (teeth), and the number of turns of one of the two wound coils is different from the number of turns of the other coil. Furthermore, one coil is wound on top of the other coil, and the number of turns of the other coil is greater than the number of turns of the first coil.

[0148] Therefore, it is possible to suppress variations in inductance or resistance values ​​between commutator segments that may occur due to a specific configuration in which the winding direction of the coil in one slot (teeth) of two slots across which the coil is wound is opposite to the winding direction of the coil in the other slot (teeth).

[0149] Although the motor of the present invention has been described above with reference to preferred embodiments, the motor of the present invention is not limited to the configuration of the above embodiments. For example, the number of magnetic poles of the magnet, the number of slots in the armature, and the number of segments of the commutator in the above embodiments are all examples and can be selected as appropriate, provided that they comply with the conditions of the present invention.

[0150] In the above embodiment, the magnet 6 is cylindrical and magnetized with two different magnetic poles (N and S poles) alternately arranged in the circumferential direction, but the present invention is not limited to this. For example, in the magnet 6 shown in Fig. 1, multiple magnetic members separated by dashed lines indicating the boundary between the S and N poles may be attached to the inner surface of the housing 5 so that the S and N poles are arranged alternately in the circumferential direction.

[0151] In addition, those skilled in the art can appropriately modify the motor of the present invention in accordance with conventionally known knowledge. As long as such modifications still comprise the configuration of the present invention, they are of course included in the scope of the present invention. [Explanation of symbols]

[0152] 1...motor, 2...rotor core, 3...coil, 4...commutator, 5...housing, 6...magnet, 7, 7', 7"...brush, 8...shaft, 9...connecting wiring, 10...armature, 20...stator, 31-39...1st to 9th coils, C1-C18...segments, T1-T9...teeth (slots)

Claims

1. A magnet and a plurality of slots facing the magnet; a coil wound across two of the plurality of slots; a commutator having a plurality of segments; a plurality of brushes each having a contact portion that contacts the plurality of segments in a circumferential direction; Equipped with a winding direction of the coil around one of the two slots across which the coil is wound is opposite to a winding direction of the coil around the other slot; A motor in which the coil wound around one slot in the circumferential direction is connected to one of two adjacent segments in the plurality of segments, and the coil wound around the other slot is connected to the other of the two adjacent segments.

2. Two coils are wound around each of the plurality of slots, 2. The motor according to claim 1, wherein the winding directions of the two coils wound in each slot are opposite to each other.

3. The motor according to claim 1 or 2, wherein two slots across which the coil is wound are adjacent to each other in the circumferential direction.

4. 3. The motor according to claim 1, wherein one or more slots different from the two slots across which the coil is wound are present in the circumferential direction between the two slots.

5. 5. The motor according to claim 1, wherein the one slot and the one segment are on one side in the circumferential direction, and the other slot and the other segment are on the other side.

6. a width of a contact portion of the brush with the commutator in the circumferential direction of the commutator is defined as x; The width of the segment in the circumferential direction of the commutator is defined as y, 6. The motor according to claim 1, wherein the following relational expression (1) is satisfied, where z is a gap between two adjacent segments in the circumferential direction of the commutator. x<y+2z ... Relational formula (1)

7. In the circumferential direction, the magnet has two different magnetic poles arranged alternately, a contact surface of a commutator that comes into contact with the contact portion of the brush in a circumferential direction includes areas corresponding to the two different magnetic poles, 7. The motor according to claim 1, wherein the contact portion of the brush is in contact with the commutator across two of the regions corresponding to the two different magnetic poles.

8. The magnet is composed of a plurality of magnetic members, The motor according to claim 1 , wherein the plurality of magnetic members are arranged in a circumferential direction.

9. Two coils are wound around each of the plurality of slots, 9. The motor according to claim 1, wherein the number of turns of one of the two coils is different from the number of turns of the other coil.

10. The other coil is wound around the one coil, 10. The motor according to claim 9, wherein the number of turns of the other coil is greater than the number of turns of the one coil.

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