JP2007053858A - Rotating electric device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the noise of an alternator 1a and improve the power generation efficiency by arranging the constitution such that the rotational speed of a cooling fan 21 does not get over a specified value even in case that the rotational speed of a rotating shaft 3 is over a specified value. <P>SOLUTION: The above cooling fan 21 is supported by the above rotating shaft 3 via a roller clutch 22. As this roller clutch 22, the one by which the connection is cut off in case that the rotational speed of the above cooling fan 21 gets over the above specified value is used. Therefore, the rotational speed of the above cooling fan 21 can be kept not to get over the above specified value. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention uses an alternator device (alternating current generator), a drive motor for an electric vehicle, and a regenerative brake, which are used to obtain electric power necessary for the vehicle by using rotation of a traveling engine of the vehicle (automobile). The present invention relates to improvements in rotating electrical machines such as power generators.

  For example, an alternator device has been conventionally used to obtain electric power used for charging a battery, including various electric devices mounted on a vehicle, by using rotation of a crankshaft connected to an engine. FIG. 10 shows a conventionally known basic configuration of such an alternator apparatus 1.

  An alternator device 1 having a conventional structure (see, for example, Patent Documents 1 and 2) is assembled adjacent to an engine (not shown), and a pair of rotating shafts 3 are disposed inside a housing 2 made of a lightweight metal such as an aluminum alloy. It is rotatably supported by rolling bearings 4a and 4b. A driven pulley 5 is fixed to a portion projecting out of the housing 2 at one axial end portion (left end portion in FIG. 10) of the rotating shaft 3. The rotation of the crankshaft of the engine can be transmitted to the rotary shaft 3 via an endless belt (not shown) that is stretched around the driven pulley 5.

  A rotor 6 is fixed at an intermediate portion in the axial direction of the rotating shaft 3 between the rolling bearings 4a and 4b. The rotor 6 is rotatable with the rotating shaft 3. The rotor 6 includes a pole core 7 that is externally fitted and fixed to the rotating shaft 3, and a rotor coil 8 that is wound around the pole core 7. Of these, on the outer diameter side portion of the pole core 7, trapezoidal claw-shaped magnetic pole pieces 9a and 9b that generate a magnetic field when an excitation current is supplied to the rotor coil 8 are arranged in the circumferential direction. They are provided alternately (see FIG. 11). In addition, a stator 10 is provided on the inner side of the housing 2 at a portion existing around the rotor 6. The stator 10 has a substantially cylindrical stator core 11 having an inner diameter dimension slightly larger than the outer diameter dimension of the rotor 6, and is wound around the stator core 11 in three phases. The stator coil 12 receives the generated magnetic field and induces an AC voltage. On the other hand, outside the housing 2, on the other axial end side (right end side in FIG. 10) of the rotating shaft 3, a rectifier 13 for converting the AC voltage induced in the stator coil 12 into a DC voltage. Alternatively, electrical components such as a voltage regulator 14 for controlling the obtained DC voltage to an appropriate value are arranged and covered with a cover 15.

  Further, a pair of cooling fans 16a and 16b are provided in a portion sandwiching the rotor 6 from both sides in the axial direction around the intermediate portion in the axial direction of the rotating shaft 3. Each of the cooling fans 16a and 16b is provided in a state where it is bent and raised in the axial direction (less than 90 degrees) at a plurality of locations in the circumferential direction near the outer diameter of the annular base 17 and the outer diameter of the base 17. The cooling blades 18 and 18 are provided. Each of the cooling fans 16a and 16b having such a configuration is configured such that, of the base portion 17, the axial one side portion opposite to the cooling blades 18 and 18 in the axial direction is connected to the rotor 6 (pole core 7). The rotor 6 is integrated with each other by being fixed to the side surfaces in the axial direction. The cooling fans 16a and 16b are driven to rotate together with the rotor 6 by the rotary shaft 3, and the rotor coil 8, the stator coil 12, the rectifying device 13, the voltage adjusting device 14 and the like that generate heat as the alternator device 1 generates power. Send cooling air to. Specifically, when the cooling fans 16a and 16b rotate, outside air in the engine room is taken in from a plurality of intake holes 19 and 19a formed in the axial side wall portions of the housing 2 and the cover 15, The outside air is allowed to flow while passing through each of the members 8, 12, 13, 14 and the like. And the air which took the heat of each of these members 8, 12, 13, 14, etc. and increased in temperature is discharged from the plurality of exhaust holes 20, 20 formed in the outer peripheral wall portion of the housing 2 (heat is released). I have to. In this way, by cooling the members 8, 12, 13, 14 and the like, the life of the members 8, 12, 13, 14 and the like is prevented from being reduced, and the power generation efficiency of the alternator device 1 is reduced. To prevent things.

By the way, in recent years, an alternator device has been required to have a high output, due to the widespread use of electronic control systems for automobiles. For this purpose, for example as described in Patent Document 2 or the like, it is rotated at a high speed rotary shaft (e.g., rotating at about maximum 17000min ^-1 ~20000min ^-1) has been performed. However, in the case of the conventional alternator apparatus 1 described above, if the rotating shaft 3 is rotated at a high speed in order to increase the output, the following problems may occur. That is, as described above, since both the cooling fans 16a and 16b are fixed to the rotor 6 that rotates together with the rotary shaft 3, both the cooling fans 16a and 16b and the rotary shaft 3 are always the same. It rotates at the rotation speed. For this reason, the rotational speed of the rotating shaft 3 is a certain value determined by the shape and outer diameter of each of the cooling fans 16a and 16b (hereinafter referred to as “first rotational speed”; the same applies throughout the present specification). If it exceeds the above, there is a possibility that an unpleasant noise of a high frequency is generated from each of the cooling fans 16a and 16b, thereby causing discomfort to the vehicle occupant. Therefore, even when the rotating shaft 3 rotates at a high speed, from the viewpoint of preventing the generation of such abnormal noise, each of the above rotating shafts 3 even when the rotating speed of the rotating shaft 3 exceeds the first rotating speed. It is desirable that the rotation speeds of the cooling fans 16a and 16b be maintained so as not to exceed the first rotation speed.

  On the other hand, the cooling efficiency of the alternator device 1 (the members 8, 12, 13, 14 and the like) is such that the rotational speeds of the cooling fans 16a and 16b are different values (hereinafter referred to as “second rotational speeds”). (The same throughout the present specification), the temperature increases with the rotational speed of the cooling fans 16a and 16b. However, if the second rotational speed is exceeded, after that, even if the rotational speed of each of the cooling fans 16a and 16b is increased, it becomes difficult to obtain a cooling efficiency commensurate with (in proportion to) the rotational speed. This is because the positions and sizes of the intake holes 19 and 19a and the exhaust holes 20 and 20, the installation positions of the members 8, 12, 13, and 14 and the temperature in the engine room, etc. This is because it is closely related to the improvement of cooling efficiency. For this reason, increasing the rotational speed of the cooling fans 16a and 16b beyond the second rotational speed causes the cooling fans 16a and 16b to be rotationally driven and the rotational shaft 3 to be rotated. This leads to an increase in energy loss related to the driving force for rotation, and as a result, the power generation efficiency of the alternator device 1 is reduced. Therefore, from the viewpoint of preventing the power generation efficiency of the alternator device 1 from being lowered, even when the rotational speed of the rotary shaft 3 exceeds the second rotational speed, the rotational speeds of the cooling fans 16a and 16b are the same. It is desirable to maintain a state that does not exceed two rotation speeds.

Japanese Patent Laid-Open No. 11-254953 JP 7-31854 A

  In view of the circumstances as described above, the present invention has a structure capable of keeping the rotation speed of the cooling fan not exceeding the predetermined rotation speed even when the rotation speed of the rotating shaft exceeds the predetermined rotation speed. Invented to realize the above. Specifically, the invention was invented to suppress an increase in the rotational speed of the cooling fan, to reduce the noise of a rotating electrical machine such as an alternator, and to improve the power generation efficiency.

The rotating electrical machine apparatus of the present invention includes a housing, a rotating shaft, a rotor, a stator, and a cooling fan, similarly to the rotating electrical apparatus such as the conventional alternator apparatus shown in FIGS.
Of these, the rotation shaft is rotatably supported in the housing and is driven to rotate by a drive source such as an engine.
Further, the rotor is fixed to an intermediate portion in the axial direction of the rotating shaft and rotates together with the rotating shaft.
The stator is disposed around the rotor inside the housing. The cooling fan is disposed around a portion of the rotating shaft that is axially separated from the rotor, and is driven to rotate by the rotating shaft.
In particular, in the rotating electrical machine apparatus of the present invention, a clutch device is provided between the inner peripheral surface of the cooling fan and the outer peripheral surface of the rotating shaft. And this clutch apparatus shall transmit a rotational force between the said rotating shaft and this cooling fan only when the rotational speed of the said cooling fan is below a predetermined value.

  In the case of the rotating electrical machine apparatus of the present invention configured as described above, when the rotation speed of the cooling fan exceeds a predetermined value, the clutch device is disconnected and the rotation between the rotating shaft and the cooling fan is performed. Cut off power transmission. For this reason, the rotational speed of the cooling fan can be kept in a state not exceeding the predetermined value. For example, if the present invention is applied to an alternator device and this predetermined value is set to the first rotational speed, even when the rotary shaft rotates at high speed, the generation of high-frequency noise from the cooling fan is prevented, The noise reduction of the alternator device can be realized. Further, if the predetermined value is set to the second rotational speed, energy loss related to the driving force for rotationally driving the rotating shaft can be suppressed, and the power generation efficiency of the alternator device can be improved. Furthermore, if the predetermined value is set to be lower than the lower rotation speed of the first rotation speed and the second rotation speed, the noise of the alternator device can be reduced and the power generation efficiency can be improved.

Preferably, when carrying out the present invention, as described in claim 2, between the inner peripheral surface of the cooling fan and the outer peripheral surface of the rotary shaft, the rotary shaft and the cooling fan are positioned adjacent to the clutch device. A support bearing is provided that can freely rotate relative to the shaft.
If comprised in this way, relative rotation with these rotating shafts and a cooling fan can be performed stably in the state from which transmission of the rotational force between the said rotating shaft and the said cooling fan was interrupted | blocked. Further, it is possible to prevent wear, abnormal heat generation, seizure and the like from occurring in the sliding contact portion and the contact portion inside the clutch device, thereby preventing the life of the clutch device from being reduced.

Further, when the present invention is implemented, preferably, as described in claim 3, the clutch device is cooled only when the rotation shaft tends to rotate relative to the cooling fan in a predetermined direction. A one-way clutch having a structure in which a rotational force can be freely transmitted to and from the fan and a centrifugal force acts in a direction in which the transmission of the rotational force is interrupted.
When carrying out the invention described in claim 3, for example, as described in claim 4 or claim 5, as a one-way clutch, a roller clutch in which a cam surface is formed on the inner peripheral surface of the outer ring ( In the case of claim 4, a disengagement type sprag clutch (in the case of claim 5) can be used.
According to the one-way clutch having such a structure, when the rotational speed of the cooling fan exceeds a predetermined value, transmission of rotational force between the rotating shaft and the cooling fan is cut off (the rotating shaft and the cooling fan). Can be realized with a simple configuration using centrifugal force.

  1 to 3 show a first embodiment of the present invention corresponding to claims 1, 3 and 4. A feature of the present invention is that a clutch device is provided between the cooling fan 21 and the rotating shaft 3 to reduce noise and improve power generation efficiency of the alternator device 1a that is a rotating electrical machine device. The structure and operation of other parts such as the entire structure of the alternator device are substantially the same as those of the conventional structure described in FIGS. For this reason, the same reference numerals are given to the equivalent parts, and the duplicated explanation is omitted or simplified, and the following description will focus on the characteristic parts of the present embodiment.

  As shown in FIG. 1, the alternator device 1 a of this embodiment is similar to the alternator device 1 of the conventional structure (see FIG. 10), on both side portions of the rotor 6 a fixed to the intermediate portion in the axial direction of the rotating shaft 3. A pair of cooling fans 16b and 21 are provided. Among these, the cooling fan 16b shown in the right part of FIG. 1 is provided in a state of being fixed to one axial side surface part (right side part in FIG. 1) of the rotor 6a, similarly to the alternator device 1 having the conventional structure. . On the other hand, the cooling fan 21 shown in the left part of FIG. 1 is supported on the rotating shaft 3 via a roller clutch 22 which is a one-way clutch. The cooling fan 21 includes a base portion 17 a having a substantially L-shaped cross section provided with a support cylinder portion 23 for fitting and fixing the roller clutch 22 on the inner diameter side thereof, and a plurality of cooling blades 18 and 18. Composed. Further, an accommodation recess 24 capable of accommodating a part of the support cylinder portion 23 and the roller clutch 22 is formed on the other axial side surface portion (the left side surface portion in FIGS. 1 and 2) of the rotor 6a, and the alternator device 1a. This prevents the axial dimension of the material from becoming too large.

  The roller clutch 22 of the present embodiment has a rotational force between the rotating shaft 3 and the cooling fan 21 only when the rotating shaft 3 tends to rotate relative to the cooling fan 21 in a predetermined direction. Enable transmission. In order to constitute the roller clutch 22 having such a configuration, an outer ring for clutch 25 is fitted and fixed to the inner peripheral surface of the support cylinder portion 23 of the cooling fan 21 by an interference fit. The inner peripheral surface of the clutch outer ring 25 is a cam surface 26. That is, on the inner peripheral surface of the outer ring for clutch 25, a plurality of concave portions 27 called ramp portions as shown in FIG. 3 are formed at equal intervals in the circumferential direction, so that the inner peripheral surface is the cam surface. 26. On the other hand, the clutch inner ring 28 is externally fixed by an interference fit on the outer peripheral surface of the axial direction intermediate portion of the rotary shaft 3 on the inner diameter side of the clutch outer ring 25. The inner ring for clutch 28 has an axially outer peripheral surface as a simple cylindrical surface 29, and both axial portions of the cylindrical surface 29 extend outward in the radial direction. I'm trying to stop.

  A plurality of rollers 30 and 30 constituting the roller clutch 22 together with the clutch outer ring 25 and the clutch inner ring 28 are provided in a clutch retainer 31 (see FIG. 3, omitted in FIGS. 1 and 2). It is supported so as to be slightly displaceable in the rolling and circumferential directions. The clutch retainer 31 is partially prevented from rotating relative to the clutch outer ring 25 by engaging a part of its outer peripheral surface with the recesses 27 formed in the cam surface 26. In addition, springs 33 are provided between the rollers 30 and 30 on one side in the circumferential direction (left side in FIG. 3) of the pillars 32 and 32 constituting the clutch retainer 31 as described above. ing. Each of these springs 33 directs each of these rollers 30 to a portion of the substantially cylindrical gap 34 formed between the cam surface 26 and the cylindrical surface 29 where the gap in the diametric direction is narrowed. It is elastically pressed in the same direction with respect to the circumferential direction. The direction in which the springs 33 press the rollers 30, 30 is rotationally driven via the driven pulley 5 fixed to one end of the axial direction (the left end in FIG. 1). In the same direction (the direction of arrow A in FIG. 3).

  In the case of the roller clutch 22 configured as described above, when the rotary shaft 3 rotates relative to the cooling fan 21 in the direction in which the springs 33 press the rollers 30, 30. The rollers 30 and 30 bite into the narrow portion of the cylindrical gap 34 in the diameter direction (becomes locked). Thereby, a rotational force can be transmitted between the rotating shaft 3 and the cooling fan 21 (the rotating shaft 3 and the cooling fan 21 are connected). As described above, the direction in which the springs 33 press the rollers 30 and 30 and the direction in which the rotary shaft 3 is rotationally driven are the same direction (the direction of arrow A in FIG. 3). Accordingly, the rotation of the rotating shaft 3 is transmitted to the cooling fan 21.

  Further, the roller clutch 22 of the present embodiment has a predetermined value when the rotational speed of the cooling fan 21 is transmitted from the rotary shaft 3 to the cooling fan 21 as described above. If it exceeds, the transmission of this rotational force is cut off (becomes an overrun state). That is, when the cooling fan 21 rotates, the rollers 30 and 30 revolve at the same speed as the cooling fan 21. Then, based on this revolving motion, centrifugal force acts on each of the rollers 30, 30, and the rollers 30, 30 are pressed against the bottom surfaces of the recesses 27. Since the bottom surfaces of the recesses 27 are inclined, the rollers 30, 30 tend to be displaced in the right direction in FIG. 3 against the pressing force of the springs 33. As the rotational speed of the cooling fan 21 increases, the centrifugal force increases (in proportion to the square of the rotational speed), and the magnitude of the circumferential component of the centrifugal force is greater than the elasticity of the springs 33. When it becomes larger, the rollers 30, 30 start moving to the deep portions of the recesses 27 while compressing the springs 33. In particular, in this embodiment, when the rotational speed of the cooling fan 21 exceeds the predetermined value, the rolling surfaces of the rollers 30 and 30 and the cylindrical surface 29 of the clutch inner ring 28 are separated from each other. Thus, the configuration of the roller clutch 22 is restricted. Specifically, the relationship between the mass of each of the rollers 30 and 30 constituting the roller clutch 22, the magnitude of the elasticity of each of the springs 33, the inclination angle of each of the concave portions (lamp portions) 27, etc. From the rotation speed set as the predetermined value, regulation is performed based on the result of experiment or calculation. Accordingly, when the rotation speed of the cooling fan 21 exceeds the predetermined value, the rolling surfaces of the rollers 30 and 30 and the cylindrical surface 29 of the clutch inner ring 28 are separated from each other, and the cooling shaft 3 is separated from the cooling shaft 3. Transmission of rotational force to the fan 21 is cut off. As long as the rotational speed of the rotating shaft 3 exceeds the predetermined value, the roller clutch 22 repeats fine connection / disconnection (or is in a semi-connected state). For this reason, the rotational speed of the cooling fan 21 can be kept in a state not exceeding the predetermined value. In the case of the present embodiment, the rolling surfaces and the cylinders are irrespective of whether the rolling surfaces of the rollers 30 and 30 and the cylindrical surface 29 of the clutch inner ring 28 are finely connected or disconnected. In order to suppress wear on the surface 29, the clutch inner ring 28 is made of a metal having self-lubricating properties, such as copper or a copper-based alloy.

  The rotation speed that can be set as the predetermined value can be arbitrarily selected within the range of the rotation speed of the rotary shaft 3 based on the configuration of the roller clutch 22. For this reason, for example, the following two rotational speeds can be adopted as the predetermined values. That is, the rotational speed at which the cooling fan 21 starts to generate high-frequency noise (the first rotational speed) and the rotational speed at which it becomes difficult to obtain a cooling efficiency (proportional to) the rotational speed of the cooling fan 21 (the above-described speed). Or the second rotation speed). In this case, the two rotation speeds can be obtained by experiments or calculations. If the predetermined value is set to the first rotation speed, it is possible to prevent high-frequency noise from the cooling fan 21 even when the rotating shaft 3 is rotated at a high speed. For this reason, the noise reduction of the alternator apparatus 1a can be realized. On the other hand, if the predetermined value is set to the second rotational speed, an optimum cooling efficiency corresponding to the rotational speed of the cooling fan 21 can be obtained, and energy loss related to the driving force for rotationally driving the rotary shaft 3 can be obtained. Can be suppressed. For this reason, the power generation efficiency of the alternator device 1a can be improved. Further, if a lower rotation speed is set as the predetermined value among the two rotation speeds, the noise of the alternator device 1a can be reduced and the power generation efficiency can be improved.

  In addition, the cooling fan 21 also has a slow rotation speed due to inertial force (inertia) even when transmission of the rotational force from the rotary shaft 3 is cut off (connection to the rotary shaft 3 is cut off). Continue rotating while lowering. When the centrifugal force acting on each of the rollers 30 and 30 decreases with the decrease in the rotation speed and the circumferential component force becomes smaller than the elastic force of each of the springs 33, these rollers 30 and 30. However, it bites into the narrow portion of the cylindrical gap 34 in the diameter direction again (becomes locked). In this way, the cooling fan 21 is rotationally driven by the rotary shaft 3 in a state where the predetermined value is not exceeded.

  On the other hand, when the rotating shaft 3 rotates relative to the cooling fan 21 in the direction opposite to the direction in which the springs 33 press the rollers 30 and 30 (in the direction of arrow B in FIG. 3), Each of the rollers 30, 30 retreats against the elastic force of each of the springs 33 in a wide portion of the cylindrical gap 34 in the diametrical gap (overrun state). That is, when the rotational speed of the rotary shaft 3 tends to be slower than the rotational speed of the cooling fan 21, the transmission of rotational force between the rotary shaft 3 and the cooling fan 21 is cut off. For this reason, when the rotational speed of the engine suddenly decreases, a braking force is applied to the rotary shaft 3, and the rotational speed of the rotary shaft 3 becomes relatively slower than the rotational speed of the cooling fan 21. Even in this case, the rotational speed of the cooling fan 21 does not decrease in synchronization with the rotational speed of the rotary shaft 3. As a result, the cooling fan 21 is rotated by inertial force (inertia), and the rotor coil 8, the stator coil 12, and the like that generate heat due to power generation can be effectively cooled.

  FIG. 4 shows a second embodiment of the present invention, which also corresponds to the first, third, and fourth aspects. Also in the case of the present embodiment, the cooling fan 21 shown in the left part of FIG. 4 is supported on the rotating shaft 3 via the roller clutch 22 as in the first embodiment. Further, in the case of the present embodiment, the cooling fan 21a shown in the right part of FIG. 4 is also supported on the rotary shaft 3 via the roller clutch 22a.

  With this configuration, in the case of the present embodiment, the cooling fans 21 and 21a can be rotated at different rotational speeds. That is, the configuration of each of the roller clutches 22 and 22a (the mass of the roller 30, the inclination angle of the recess 27, the magnitude of the elasticity of the spring 33 (see FIG. 3), etc.) is made different from each other. The rotational speed (predetermined value) at which the transmission of the rotational force between the cooling fans 21 and 21a is interrupted can be set separately for each of the cooling fans 21 and 21a. For this reason, if a predetermined value is set for each of the cooling fans 21 and 21a in accordance with the amount of heat generated by the members 8, 12, 13, and 14 that generate heat during power generation, the members 8, 12, 13, and It becomes possible to cool 14 etc. effectively. In this case as well, if the predetermined value is set to a speed equal to or lower than the lower rotational speed of the first rotational speed and the second rotational speed, the alternator device 1b can be reduced in noise and power generation efficiency. Improvement can be realized at a higher level. Further, if the predetermined values for both the cooling fans 21 and 21a are set to the same rotational speed and the roller clutches 22 and 22a are made common, the cost can be reduced by reducing the number of parts. In the case of the present embodiment, the support cylinder portions 23 of the cooling fans 21 and 21a are housed in the housing recesses 24 and 24 formed on both side surfaces in the axial direction of the rotor 6b, so that the alternator device 1b This prevents the axial dimension from becoming too large. Other configurations and operations are the same as those of the first embodiment.

  5 to 6 show a third embodiment of the present invention corresponding to claims 1 to 4. In the case of the present embodiment, of the pair of cooling fans 16b and 21b constituting the alternator device 1c, the space between the inner peripheral surface of the cooling fan 21b and the outer peripheral surface of the rotary shaft 3 shown in the left part of FIG. In addition, a roller clutch 22 and a support bearing 35 are provided. Of these, the support bearing 35 smoothly performs relative rotation between the rotary shaft 3 and the cooling fan 21b when transmission of the rotational force between the rotary shaft 3 and the cooling fan 21b is cut off. It is provided for this purpose. In the illustrated example, the support bearing 35 is a single row deep groove type ball bearing having a high moment rigidity, and more preferably a four-point contact type ball so as to support a moment or the like acting with the rotation of the cooling fan 21b. Rolling bearings such as bearings are used. Further, the cooling fan 21b is a support cylinder having a larger axial dimension than the first and second embodiments, so that the roller clutch 22 and the support bearing 35 are fitted and fixed to the inner diameter side thereof. A portion 23a is provided. In accordance with this, a housing recess 24a is provided on one axial side surface of the rotor 6c (the left side surface in FIGS. 5 and 6) to prevent the alternator device 1c from increasing in size in the axial direction. Yes.

  In order to constitute the support bearing 35 as described above, the support bearing outer ring 36 is fitted and fixed to the inner peripheral surface of the support cylinder portion 23a by interference fitting, and the axially intermediate portion outer peripheral surface of the rotary shaft 3 is fixed. The support bearing inner ring 37 is externally fixed by an interference fit. A plurality of balls 38 are rotatably provided between the inner peripheral surface of the support bearing outer ring 36 and the outer peripheral surface of the support bearing inner ring 37. With such a configuration, when the connection between the cooling fan 21b and the rotary shaft 3 is broken, a moment acting on the cooling fan 21b can be supported by the support bearing 35. For this reason, the behavior of the cooling fan 21b can be stabilized. In addition, excessive wear, abnormal heat generation, and further seizure may occur at the sliding contact portions of the rolling surfaces of the rollers 30 and 30 constituting the roller clutch 22 and the cylindrical surface 29 of the inner ring 28 for clutch. Can be prevented. For this reason, the lifetime reduction of the roller clutch 22 can be prevented. The support bearing inner ring 37 and the clutch inner ring 28 can be integrated to reduce the cost. Other configurations and operations are the same as those of the first embodiment.

  7 to 9 show a fourth embodiment of the present invention corresponding to the first, third, and fifth aspects. In the case of the alternator device 1d of this embodiment, the clutch device provided between the cooling fan 21c and the rotating shaft 3 is a disengagement type sprag clutch 39 that is a one-way clutch. Similarly to the roller clutch 22 of each of the first to third embodiments, the sprag clutch 39 is also used only when the rotary shaft 3 tends to rotate relative to the cooling fan 21c in a predetermined direction. It is possible to freely transmit the rotational force between the cooling fan 21c and the cooling fan 21c. Similarly, when the rotational speed of the cooling fan 21c exceeds a predetermined value, the sprag clutch 39 is disconnected from the rotational force between the rotary shaft 3 and the cooling fan 21c. It has a configuration.

  In order to constitute such a sprag clutch 39, an outer ring for clutch 25a is fitted and fixed to the inner peripheral surface of the support cylinder portion 23 provided in the cooling fan 21c. The outer ring for clutch 25 a is provided with an outer diameter side cylindrical surface 40 on the inner peripheral surface of the axially intermediate portion thereof, and is provided with flanges 41 a and 41 a having inward flange shapes on both side portions of the outer diameter side cylindrical surface 40. On the other hand, the inner ring for clutch 28a is fitted and fixed to the outer peripheral surface of the intermediate portion in the axial direction of the rotary shaft 3. The inner ring for clutch 28 a is provided with an inner diameter side cylindrical surface 42 on the outer peripheral surface of the axially intermediate portion thereof, and is provided with flanges 41 b and 41 b having outward flange shapes on both side portions of the inner diameter side cylindrical surface 42. A plurality of sprags 43, 43 each having a non-circular cross-sectional shape, each being a locking member, are provided between the outer diameter side cylindrical surface 40 and the inner diameter side cylindrical surface 42. It is provided in the state held in In the case of this embodiment, each of the sprags 43, 43 is composed of an outer diameter side cam portion 44 and an inner diameter side cam portion 45, each of which is formed in a partially arcuate convex shape. It is located on the inner diameter side cam portion 45 side. Further, the sprags 43, 43 are prevented from coming off in the axial direction by the two flange portions 41a, 41b.

  The sprags 43, 43 are given elastic force in the direction of pressing (stretching between both surfaces) against the outer diameter side cylindrical surface 40 and the inner diameter side cylindrical surface 42 by the elastic member 46. Further, the elastic member 46 used in this embodiment includes a spring 33 a that presses the outer diameter side cam portion 44 and a spring 33 b that presses the inner diameter side cam portion 45. Further, the elastic member 46 applies elasticity to each of the sprags 43, 43 through the driven pulley 5 in which the rotary shaft 3 is fixed to one axial end portion (left end portion in FIG. 7). 9 (A) and 9 (B), when they are driven to rotate in the direction of the arrow C, the friction between the outer and inner cylindrical surfaces 40, 42 and the sprags 43, 43 causes these The direction of the moment applied to each sprag 43, 43 (counterclockwise in FIG. 9) is made to coincide.

  In the sprag clutch 39 configured as described above, as shown by the arrow C in FIG. 9A, the rotary shaft 3 is in the cooling fan 21c, and the elastic member 46 is in the sprags 43, 43. When the sprags 43 and 43 tend to rotate in the opposite direction (clockwise) to the direction in which they are pressed (counterclockwise), the sprags 43 and 43 are connected to the outer diameter side cylindrical surface 40 and the inner diameter side cylindrical surface 42. Stretch between (becomes locked). Thereby, a rotational force can be transmitted between the rotating shaft 3 and the cooling fan 21c (the rotating shaft 3 and the cooling fan 21c are connected). That is, the rotation of the rotating shaft 3 is transmitted to the cooling fan 21c.

  Further, the sprag clutch 39 of the present embodiment has a predetermined rotational speed of the cooling fan 21c even when the rotational force is transmitted from the rotary shaft 3 to the cooling fan 21c as described above. If it exceeds, the operation is performed as shown in FIG. 9B, and the transmission of this rotational force is cut off (overrun state is entered). That is, when the rotating shaft 3 rotates, centrifugal force acts on the sprags 43 and 43. Further, the center of gravity of each of the sprags 43, 43 exists on the opposite side of the contact position with the outer-diameter side cylindrical surface 40 with respect to the circumferential direction with respect to the swing center of each of the sprags 43, 43. For this reason, the sprags 43 and 43 tend to be displaced from the standing state to the tilted state by the centrifugal force accompanying the revolution speed of the sprags 43 and 43. Specifically, each of the sprags 43 and 43 is configured such that the inner diameter side cam portion 45 of the spring 33b is in a state where the outer peripheral side cam portion 44 is in contact with the outer diameter side cylindrical surface 40. It tends to be displaced radially outward against the elasticity. In particular, in the case of the present embodiment, when the rotational speed of the rotary shaft 3 exceeds the predetermined value, the peripheral surface of the inner diameter side cam portion 45 is separated from the inner diameter side cylindrical surface 42. The configuration of the sprag clutch 39 is regulated. Specifically, the shape of the sprags 43, 43 (outer diameter side cam portion 44, inner diameter side cam portion 45) constituting the sprag clutch 39, the position of the center of gravity, the elastic member 46 (respective springs 33a, 33b). The degree of elasticity and the like are regulated based on the results of experiments or calculations from the rotational speed set in advance as the predetermined value. Therefore, when the rotational speed of the cooling fan 21c exceeds the predetermined value, the peripheral surface of the inner diameter side cam portion 45 and the inner diameter side cylindrical surface 42 are separated from each other, and the rotation shaft 3 is connected to the cooling fan 21c. Transmission of rotational force is cut off. Therefore, the rotation speed of the cooling fan 21c can be kept in a state not exceeding the predetermined value. Also in this embodiment, the clutch inner ring 28a is made of a metal having a self-lubricating property in order to suppress wear of the contact portion between the peripheral surface of the inner diameter side cam portion 45 and the inner diameter side cylindrical surface 42. The product has a so-called sliding bearing function. Similarly, the clutch outer ring 25a can be made of a metal having self-lubricating properties.

  On the other hand, the rotating shaft 3 matches the direction in which the elastic member 46 presses each of the sprags 43, 43 against the cooling fan 21c, in the counterclockwise direction of FIG. 9 (FIG. 9A). When the relative rotation is performed in the direction indicated by the arrow D in (B), each of the sprags 43 and 43 slides with respect to one or both of the outer diameter side cylindrical surface 40 and the inner diameter side cylindrical surface 42 (overrun state). Become). That is, when the rotational speed of the rotary shaft 3 tends to be slower than the rotational speed of the cooling fan 21c, the transmission of rotational force between the rotary shaft 3 and the cooling fan 21 is cut off.

In this embodiment, since the disengagement type sprag clutch is used as the one-way clutch, the torque capacity that can be transmitted is increased as compared with the cases of the first to third embodiments that use the roller clutch. Can do. For this reason, it can be preferably used for an alternator device incorporated in a large vehicle such as a large cooling fan can be used. Other configurations and operations are the same as those of the first embodiment.
In addition, this invention is not limited to the structure provided with two cooling fans around the rotating shaft, but can be applied to an alternator device provided with one or more cooling fans. Of course, the present invention can be applied to a structure provided with a cooling fan outside the housing constituting the alternator device. Further, the rotation speed set to the predetermined value is not limited to the first rotation speed or the second rotation speed, but is optimized in consideration of various conditions such as the shape of the cooling fan to be used and use conditions. You can set the speed. The present invention is naturally applicable not only to the alternator devices shown in the first to fourth embodiments, but also to various types of rotating electrical machines such as a drive motor for an electric vehicle and a power generator for a regenerative brake.

Sectional drawing which shows Example 1 of this invention. The A section enlarged view of FIG. FIG. 3 is an enlarged cross-sectional view taken along the line BB in FIG. 2. Sectional drawing which shows Example 2 of this invention. Sectional drawing which shows the same Example 3. FIG. The C section enlarged view of FIG. Sectional drawing which shows Example 4 of this invention. The D section enlarged view of FIG. (A) is a locked state, (B) is an overrun state, and each is an enlarged EE schematic cross-sectional view of FIG. Sectional drawing which shows an example of the alternator apparatus of a conventional structure. The perspective view which takes out similarly the rotor, the cooling fan integrally provided in this rotor, and the stator.

Explanation of symbols

1, 1a, 1b, 1c, 1d Alternator device 2 Housing 3 Rotating shaft 4a, 4b Rolling bearing 5 Driven pulley 6, 6a, 6b, 6c Rotor 7 Pole core 8 Rotor coil 9a, 9b Claw-shaped magnetic pole piece 10 Stator 11 Stator core 12 Stator Coil 13 Rectifier 14 Voltage regulator 15 Cover 16a, 16b Cooling fan 17, 17a Base 18 Cooling blade 19, 19a Intake hole 20 Exhaust hole 21, 21a, 21b, 21c Cooling fan 22, 22a Roller clutch 23, 23a Support cylinder 24, 24a Storage recess 25, 25a Clutch outer ring 26 Cam surface 27 Recess 28, 28a Clutch inner ring 29 Cylindrical surface 30 Roller 31 Clutch retainer 32 Column 33, 33a, 33b Spring 34 Cylindrical clearance 35 Support bearing 36 Support axis Yogairin 37 support bearing inner ring 38 ball 39 sprag clutch 40 the outer diameter side cylindrical surface 41a, 41b flange portion 42 the inner diameter side cylindrical surface 43 sprags 44 outer diameter side cam portion 45 the inner diameter side cam portion 46 elastic member

Claims (5)

  A housing, a rotary shaft rotatably supported in the housing and driven to rotate by a driving source, a rotor fixed to an intermediate portion in the axial direction of the rotary shaft and rotating together with the rotary shaft, and an inner side of the housing A stator disposed around the rotor, and a cooling fan disposed around a portion of the rotating shaft that is axially separated from the rotor and driven to rotate by the rotating shaft. In the rotating electrical machine apparatus, only when the rotational speed of the cooling fan is below a predetermined value between the inner peripheral surface of the cooling fan and the outer peripheral surface of the rotary shaft, A rotating electrical machine characterized by providing a clutch device for transmitting rotational force between the two.   The support bearing which makes free the relative rotation of these rotating shafts and a cooling fan is provided in the position adjacent to a clutch apparatus between the internal peripheral surface of a cooling fan, and the outer peripheral surface of a rotating shaft. The rotating electrical machine device described.   Only when the rotating shaft tends to rotate relative to the cooling fan in a predetermined direction, the clutch device can freely transmit the rotational force between the rotating shaft and the cooling fan, and the centrifugal force can be rotated. The rotating electrical machine apparatus according to claim 1 or 2, which is a one-way clutch having a structure that acts in a direction to cut off force transmission.   The rotating electrical machine apparatus according to claim 3, wherein the one-way clutch is a roller clutch in which a cam surface is formed on an inner peripheral surface of an outer ring.   The rotating electrical machine apparatus according to claim 3, wherein the one-way clutch is a disengagement type sprag clutch.

Images