JPH02266854A - Starter and generator for engine - Google Patents

Abstract

PURPOSE:To restrain the temperature rise of a semiconductor element for conducting a stator coil upon starting an engine by a method wherein a driving circuit is constituted of a substrate, consisting of a heat conductive material and provided with semiconductor elements so as to be capable of conducting heat, while the heat capacity of the substrate is designed so as to have a value to cope with the generating amount of heat of the semiconductor elements in a predetermined period of time. CONSTITUTION:A power module 47 is constituted of a casing 56 and eight pieces, for example, of semiconductor elements (FET) 57 provided in the casing 56. The casing 56 is constituted of a material, prominent in conductivity and heat conductivity such as aluminum and the like, and is provided with a heat capacity to cope with the generating amount of heat of the FET 57 during a predetermined period of time. Accordingly, heat is generated from the FET 57 during the period of conduction by the switching effect of the FET 57 upon starting an engine, however, heat, generated from the FET 57 may be absorbed by the casing 56. According to this method, the temperature rise of the FET 57 may be restrained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an engine starting/power generation device that integrates a starting motor and a charging generator.

(Prior art) Conventionally, an engine starting/power generation device was developed in Japanese Patent Application Laid-Open No.
As described in Japanese Patent No. 8370, a permanent magnet rotor assembly having permanent magnets on the rotor shaft and a stator assembly having multiphase (three-phase) stator windings in the housing are provided to operate as a starting motor. In this case, the stator winding is energized by a semiconductor device, and when operating as a charging generator, the three-phase current generated in the stator winding is rectified and extracted. Then, an annular recess is formed on the axial side surface of the rotor body, a cylindrical wall is formed in the housing corresponding to the recess, and semiconductor devices are attached to both the inside and outside of this cylindrical wall. Cool the device with cooling air drawn in by a fan.

(Problem to be Solved by the Invention) However, in the conventional starting/power generation device described above, the semiconductor device and the stator winding are arranged in the same space in the housing, so the semiconductor device is attached to the stator. There is a problem in that the temperature of the semiconductor device tends to rise when the engine is restarted immediately after being stopped because the influence of heat generated by the windings cannot be avoided.

In addition, in the above-mentioned starting/power generation device, in order to conduct a three-phase current to the three-phase stator winding of the stator assembly by a semiconductor device, each terminal of a plurality of semiconductor devices is interconnected, and However, since these devices must be connected to the three-phase stator winding, the wiring around the semiconductor devices becomes complicated, resulting in problems such as reduced assembly work efficiency.

The engine starting/power generation device of the present application has been made in view of the above-mentioned problems, and the first invention is aimed at suppressing the temperature rise of the semiconductor element for energizing the stator coil at the time of starting the engine, and The object of the second invention is to simplify wiring around a semiconductor element.

(Means for Solving the Problems) A first invention rotatably supports a shaft connected to a crankshaft of an engine in a manner capable of transmitting power to a housing,
A drive circuit that fixes a rotating field pole to the shaft and a stator coil wired in three phases to the housing, and supplies a three-phase current to the stator coil to generate engine starting torque in the shaft; In an engine starting/power generation device including a power generation circuit that extracts electric power generated in the stator coil by rotation of a crankshaft after startup, the drive circuit is fixed to a substrate made of a thermally conductive material and a semiconductor element is fixed to the substrate for heat conduction. The gist is that the heat capacity of the substrate is set to a value corresponding to the amount of heat generated by the semiconductor element over a predetermined period of time. rotatably supports a shaft connected to the shaft, a rotating field 5f one pole is fixed to the shaft, and a stator coil connected in three phases is fixed to the housing,
Starting an engine that is equipped with a drive circuit that applies a three-phase current to the stator coil to generate engine starting torque on the shaft, and a power generation circuit that extracts the electric power generated in the stator coil by rotation of the crankshaft after the engine is started.・
In the power generation device, a partition member made of an insulating material is provided between the drive circuit and the stator coil, and the drive circuit is fixed to a substrate made of a conductive material with one terminal electrically connected to the semiconductor element. However, the gist is that one terminal of the semiconductor element is connected to the battery or the stator coil via the substrate, and that the substrate of the drive circuit is supported by the partition member.

(Function) According to the engine starting/power generation device according to the first aspect of the invention, the semiconductor element is provided on the substrate so as to be able to conduct heat, and the substrate has a heat capacity corresponding to the amount of heat generated by the semiconductor element. Therefore, the heat generated by the semiconductor element that is energized when the engine is started is absorbed by the substrate, thereby suppressing the rise in temperature of the semiconductor element.

Furthermore, according to the engine starting/power generation device according to the second aspect of the invention, one terminal of the semiconductor element is connected through the substrate, so that the wiring around the semiconductor element can be simplified. Since the partition member is interposed between the stator coil and the drive circuit, mutual thermal interference between the stator coil and the drive circuit can also be prevented.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

1 to 6 show an engine starting/power generation device according to an embodiment of the present invention, in which FIG. 1 is an overall sectional view together with a power transmission mechanism from the engine, and FIG. 2 is an enlarged sectional view of main parts. , FIG. 3 is a sectional view taken along the lTl-l11 arrow in FIG. 2,
Figure 4 is a sectional view taken along the rV-rV arrow in Figure 2, and Figure 5 (a).
is a plan view of the main parts, and Fig. 5(b) is the V of Fig. 5(a).
-V arrow sectional view, FIG. 6 is a partial circuit diagram.

In FIG. 1, E is an engine, T is a planetary gear type transmission, and S is a starter generator (hereinafter referred to as stag) that integrates a starter motor and a charging generator. A flange joint 11a is provided at the end with a spline or the like, and the transmission T is connected via the flange joint 11a.
is connected to. The outer periphery of the flange joint 11a is supported by the crankcase of the engine E or the like with a ball bearing 12.

The transmission T includes a well-known sun gear 14, a planetary gear 15, and a housing 13 fixed to the outer wall of the engine E.
An electromagnetic clutch 18 houses a set of planetary gear mechanism P having a carrier 17 and a ring gear 16, and the ring gear 16 of this planetary gear mechanism P is provided in the housing 13.
When it is restrained, it is released and the gear shift is activated. The planetary gear mechanism P is
A sun gear 14 is integrally formed with the output shaft 19, and a carrier 17 is connected to the aforementioned flange joint 11a via a bushing 20 made of an elastic material such as rubber. A one-way clutch 21 that only allows power transmission to the output shaft 19 is interposed, and a plurality of locking holes (not shown) are formed in the ring gear 16 at regular intervals in the rotational direction.
The electromagnetic clutch 18 has a locking pawl in the housing 13 that is supported by a spring so as to be able to swing away from the locking hole of the ring gear 16, and the locking pawl is supported in response to the operation of the ignition key when the engine is started. Force it with a solenoid to lock it in the locking hole. The housing 13 is attached to the output shaft 19.
A crank pulley 22 is fixed to the end projecting outward, and a belt 25 is hung between the crank pulley 22 and a pulley 24 provided on the shaft 23 of the stag S so as to be able to transmit power. This transmission T locks the ring gear 16 with an electromagnetic clutch 18 when starting the engine, etc., and decelerates the power of the stag S and transmits it to the crankshaft 11.

In the Stag S, a housing 26 formed by joining two half-rests 27 and 28 is attached to the upper part of the engine E, and a shaft 23 is rotatably supported by the housing 26. Half holidays 27 and 28 are cylindrical walls 27a and 28, respectively.
a and the end wall 27b.

28b, and has a substantially bottomed cylindrical shape, and
．． 28 has an opening connected thereto to define a mechanism chamber 29.

The half body 28 has a bearing hole 32a and a ventilation hole 3 in the end wall 28b.
3a, an open hole 34a is formed in the cylindrical wall 28a adjacent to the left side of the stator coil, which will be described later, and the half body 27
A bearing hole 32b and an air hole 33b are formed in the end wall 27b, and an open hole 34b is formed in the cylindrical wall 27a adjacent to the right side of the stator coil, which will be described later. Half-day 28 ventilation hole 3
3a penetrates the end wall 28b and communicates the mechanism chamber 29 with a cooling air passage which will be described later.
A shaft 23 is rotatably supported on 2b via a ball bearing.

A permanent magnet 35 having a large number of poles in the rotational direction is fixed to the left end in the figure that protrudes from the end wall 28b of the half body 28, and the right end in the figure that protrudes from the end wall 27b of the half body 2F. The above-mentioned pulley 24 is fixedly installed in the mechanism chamber 29, and a rotor 36 is fixedly installed in the intermediate portion within the mechanism chamber 29. The rotor 36 is
Two yoke half-holes 36a, 36b are fixed to the shaft 23, and a field coil 37 is held between these yoke half-holes 36a, 36b. York half-day 36a,
36b has opposing ends interlaced with each other in a comb shape, and a large number of magnetic poles are generated alternately in the circumferential direction on the outer periphery by excitation of the field coil 37. These yoke halves 36a,
36b has cooling fans 38a on both sides in the axial direction.
, 38b are attached. field coil 37
is connected to a slip ring 39 provided on the shaft 23 on the right side of the figure, and is connected to a voltage regulator 40 disposed on the right side of the mechanism chamber 29 via a brush 41 that contacts this slip ring 39. As is well known, the voltage regulator 40 is connected to the field coil 3
Controls the field current flowing through 7.

A stator 42 is fixed to the inner wall of the mechanism chamber 29 of the housing 26 outside the rotor 36 .

The stator 42 includes a plurality of starting coils 44 arranged alternately in the circumferential direction on an annular yoke 43 fixed to the inner wall of the housing 26.
The starting coil 44 and the generating coil 44 (not shown in the figure and given the same number as the starting coil) are each wound in a distributed manner, and the starting coil 44 and the generating coil 44 are star-connected.

The starting coil 44 is connected to a drive circuit to be described later, and the power generation coil 44 is connected to a rectifier circuit 45 arranged on the right side of the mechanism chamber 29 in the figure. The rectifier circuit 45 is a known full-wave rectifier circuit made of diodes, etc., and is connected to a battery via a relay (not shown). This relay has a contactor that responds to the operation of the Ivnirasin key to the start position, etc., and disconnects the rectifier circuit 45 from the battery when the starting coil 44 is energized.

Further, a substantially cylindrical case 30 is fixed to the housing 26 and is formed by joining two members to the left side surface of the end wall 28b in the drawing. In the case 30, the left side in the figure on the side of the end wall 28b is entirely opened to define a circuit chamber 31 between the end wall 28b and the left side in the figure. A substantially cylindrical cylindrical member 46 is disposed coaxially with the case 30 in the zero circuit chamber 31 formed, and six power modules 471,
422, 473, 474.4711.476 (hereinafter represented by numbers without subscripts as necessary) are arranged. The cylindrical member 46 is made up of a large cylindrical portion 46a and a small cylindrical portion 46b separated by a partition wall 46c, and the right end opening of the small cylindrical portion 46b in the figure is joined to the outer edge of the bearing 32a of the half body 28, and the left end of the shaft 23 is connected to the outer edge of the bearing 32a of the half body 28. The left end opening of the large cylindrical portion 46a in the figure is open as the attachment hole 30a. In this cylinder member 46, a control circuit 48 is housed in a large cylinder part 46a, and a control circuit 48 is housed in a small cylinder part 46a.
A Hall element 49 is fixed on the inner wall of the magnet 6b in the vicinity of the permanent magnet 35 described above. The Hall element 49 is connected to the partition wall 46
It is connected to the control circuit 48 by a harness passing through c, and the permanent magnet 35 detects the rotational position of the shaft 23 and outputs a detection signal. The control circuit 48 includes a controller including a microcomputer, a drive circuit for driving the electromagnetic clutch 18 described above, a delay circuit for delaying the energization of the starting coil 44 than the energization of the electromagnetic clutch 18, and the like. This control circuit 48 is connected to each power module 47, an ignition key switch, etc., and determines the phase of the current flowing to the starting coil 44 based on the detection signal output by the wheel element 49 when the engine is started, and converts the drive signal into a power source. Output to module 47.

The power module 47 is arranged concentrically within the circuit chamber 31 outside the cylindrical member 46, and has both axial ends fixed to substantially annular holding members (partition members) 50 and 51, respectively.

As shown in detail in Figure yM2, the holding member 50 on the right side of the figure has annular plates 50a and 5 made of an insulating material such as Bakelite.
0b, and is fixed to the end wall 28b of the half body 28. Similarly, the holding member 51 on the left side of the figure is made of an insulating material and is made of annular plates 51a and 51b joined together.
It is fixed to the inner wall at the left end in the figure. A busper 52, which will be described later, is sandwiched between the annular plates 51a and 51b in the holding member 51, and three buspars 53, 54, and 55, which will be described later, are sandwiched between the annular plates 50a and 50b in the holding member 50. There is. The power module 47 is configured by providing eight PMOS-FET pair chips (hereinafter abbreviated as FET) 57 in a relatively thick, generally plate-shaped casing 56 . The casing 56 is made of a material with excellent conductivity and thermal conductivity, such as aluminum, and houses eight FETs 5.
It has a heat capacity corresponding to the amount of heat generated in a predetermined time period of 7. This casing 56 extends orthogonally in the radial direction and in the axial direction, and both ends in the axial direction are fixed to the aforementioned holding member 50.51, and the casings 56 of the six bag modules 47 are arranged in a hexagonal cylindrical shape as a whole. ing. In addition, 58a, 5
8b is a knock bottle for positioning. These casings 56 have a plurality of cooling fins 60 formed on their radially inner surfaces, and their inner surfaces define cooling air passages 59 extending in the axial direction between the casings 56 and the cylindrical member 46 described above. This cooling air passage 5
Cooling fins 60 protrude within 9. The left end of the cooling air passage 59 in the figure is open to the outside through the outside air hole 30b, and the right end in the figure is open to the mechanism chamber 29 through the ventilation hole 33a. As shown in FIG. 3, the cooling fins 60 protrude substantially in parallel toward the center in a stepped manner and extend in the axial direction.

Further, as shown in FIGS. 5(a) and 5(b), the casing 56 has the above-mentioned eight FETs 57 mounted on its radially outer surface.
A strip electrode 61 is fixed between these rows, and a strip electrode 82a having a built-in resistor is provided on the outside of each row.
62b are arranged in parallel with the 57 rows of FETs. FET
A drain electrode is formed on the joint surface of the fifth frame with the casing 56, and this drain electrode is plated with nickel or the like and fixed to the casing 56 with solder or the like so as to be electrically and thermally conductive. These FETs 57 each have a source electrode connected to a strip electrode 61 and a strip electrode 61 corresponding to the FET row.
2a and 62b, and are connected in parallel as a whole. The strip electrode 61 is provided with an insulating sheet 6 on the casing 56.
Similarly, the strip electrodes 62a, 62b
is also fixed on the casing 56 via insulating sheets 64a, 64b. The radially outer portion of the casing 56 is closed with a lid 65 made of synthetic resin such as epoxy, and silicone gel 66 is sealed inside.

The six power modules 47 described above are connected to the starting coil 44 of the stator 42, as shown in FIG. 6, and constitute a drive circuit 67 that supplies three-phase current to the starting coil 44. As seen in FIGS. 3, 4 and 6, three power modules 47. ．． 472.47s is an arc-shaped busper 5 in which the drain of the FET 57, that is, the right end of the casing 56 is held between the aforementioned holding members 51.
Buspars 53 .
Power modules 474, 475 .
476, that is, the left end of the casing 56, and the gate of the FET 57, that is, the strip electrode 62a,
62b is connected to the control circuit 48 by a harness or the like (not shown). In addition, three power modules 474°47
5.476 is a busper 6F3(
The source is connected to the three terminals of the starting coil 44 through a busper 69 (only one is shown in the figure).
(only one is shown explicitly) is connected to the left end of the half-circuit 28 and grounded via the half-circuit 28, and its gate is connected to the control circuit 48. As clearly shown in FIG. 2, the bus spar 69 extends in the axial direction outside the power module 47 in the radial direction, and has a bent portion 69a formed in an intermediate portion thereof.
9a is in contact with the lid 65 and holds the lid 65.

Next, the operation of the embodiment will be explained.

The Stag S can be used as a starting motor when the field coil 37 is connected to the battery via the voltage regulator 40 and energized, and when the starting coil 44 of the stator 42 is energized with three-phase current at the time of starting the engine.
When the rectifier circuit 45 of the stator 42 is connected to the battery via a relay after the engine is started, the stator 42 functions as a charging generator that generates electricity using the power generation coil 44.

When starting the engine, the electromagnetic clutch 18 of the transmission T is energized by operating the ignition key to the start position, and when a predetermined period of time has elapsed after the start of energizing the electromagnetic clutch 18, the starting coil 44 is energized. Start. Therefore, in the transmission T, the locking pawl of the electromagnetic clutch 18 enters the locking hole of the ring gear 16, and the ring gear 1
After this, the Stag S is driven as a starting motor, and the output of the Stag S is decelerated by the transmission T and transmitted to the crankshaft 11 of the engine E, and the engine E is started by the Stag S. Here, at the time of starting the engine, the drive circuit 67 passes a three-phase current to the starting coil 44 by the switching action of the FET 57, and the FET 57 generates heat during the energization period.
Since the heat generated by 57 is absorbed by the casing 56, F
The temperature rise of ET57 is suppressed.

Next, when Nishijin E is started, in the transmission T, the electromagnetic clutch 18 is de-energized and the ring gear 16 is released, and in the Stag S, the starting coil 44 is de-energized and the rectifier circuit 45 is de-energized. is connected to the battery. Therefore, the stag S is driven by the engine E via the transmission T to generate electricity, and the three-phase current generated in the power generation coil 44 is rectified by the rectifier circuit 45. During power generation, the cooling fans 38a and 38b of the stag S rotate integrally with the shaft 23, and the cooling fan 38a blows cooling air from the outside air hole 30b to the cooling air path as shown by the arrow in FIG. 59 and the ventilation hole 33a to the open hole 34a, each power module 47 and the left side of the coil 44 of the stator 42 in the figure are cooled, and the cooling fan 3
8b, the cooling air flows from the outside air hole 33b through the mechanism chamber 29 to the open hole 34b, thereby cooling the rectifier circuit 45, the voltage regulator 40, and the right side of the coil 44 of the stator 42 in the drawing. Therefore, the power module 47, the coil 44 of the stator 42, etc. can be effectively cooled. Furthermore, since the stator 42 and each power module 47 are isolated by the holding member 51 and the end wall 28b, there is no thermal influence on each other, and the power module 47 is FET
The temperature of the FET 57 can be prevented from rising, and the temperature of the FET 57 can be lowered when the engine is restarted immediately after being stopped.

On the other hand, in Stag S, each power module 47 is an FET.
57 is directly attached to the casing 56 in a conductive manner, and the power modules 47 are arranged concentrically, wiring for the power modules 47 can be simplified. A shortening of 53.54.55° and matching of resistance values can be achieved.

In addition, in the embodiment described above, the half body 28 has the end wall 28b, but it goes without saying that the present invention can be achieved without requiring the end wall 28a.

(Effects of the Invention) As explained above, according to the engine starting/power generation device according to the first invention, the drive circuit for supplying a three-phase current to the starting coil is provided with a semiconductor element on a substrate having a predetermined heat capacity. Since it is attached and configured to allow heat conduction, the heat generated by the semiconductor element when the engine is started can be absorbed into the substrate, and the temperature rise of the semiconductor element can be suppressed.

Further, according to the engine starting/power generation device according to the second invention, the drive circuit is configured by connecting the semiconductor element to the conductive substrate with one terminal conductively connected, and the substrate is connected to the drive circuit and the stator coil. Since it is fixed to a partition member interposed between the stator coils and supported through the partition member, the wiring attached to the drive circuit can be simplified, and mutual thermal interference between the drive circuit and the stator coil can be prevented.

[Brief explanation of drawings]

1 to 6 show an engine starting/power generation device according to an embodiment of the present invention, in which FIG. 1 is an overall view, FIG. 2 is an enlarged sectional view of main parts, and FIG. III-III arrow sectional view, Fig. 4 is the ■-rV arrow sectional view of Fig. 2, Fig. 5
Figure (a) is a plan view of the main parts, Figure 5 (b) is Figure 5 (
A sectional view taken along line V-V in a) and FIG. 6 are partial circuit diagrams. E...Engine S...Start generator (stag) 26...Housing 29...Mechanism room 30b.
・φ Outside air hole 31...Circuit chamber 33a...Vent hole 33b...Outside air hole 34a, 34b---Open hole 36...Rotor 38a, 38b---Fan 44...Starting coil ( Power generation coil) 48...Control circuit 50.51...Holding member 6...Cheering gear...FET (semiconductor element) 9...Cooling air path 6o...Cooling fin 7...
・Drive circuit patent

Claims (4)

[Claims] (1) A housing rotatably supports a shaft connected to the engine crankshaft for power transmission, a rotating field pole is fixed to the shaft, a stator coil wired in three phases is fixed to the housing, and An engine starting system equipped with a drive circuit that applies three-phase current to the stator coil to generate engine starting torque on the shaft, and a power generation circuit that extracts the electric power generated in the stator coil by rotation of the crankshaft after the engine is started. In the power generation device, the drive circuit is configured by fixing a semiconductor element to a substrate made of a thermally conductive material in a heat conductive manner, and the heat capacity of the substrate is set to a value corresponding to the amount of heat generated by the semiconductor element in a predetermined time. Starting the engine, which is characterized by the settings
Power generator. (2) A radiation fin is formed on one surface of the substrate to define a cooling air path on one surface of the substrate, and a cooling fan is provided that rotates integrally with the shaft and generates cooling air in the cooling air path. An engine starting/power generation device characterized by: (3) A shaft connected to the engine crankshaft for power transmission is rotatably supported in the housing, a rotating field pole is fixed to the shaft, a stator coil connected in three phases is fixed to the housing, and An engine starting system equipped with a drive circuit that applies three-phase current to the stator coil to generate engine starting torque on the shaft, and a power generation circuit that extracts the electric power generated in the stator coil by rotation of the crankshaft after the engine is started. In the power generation device, a partition member made of an insulating material is provided between the drive circuit and the stator coil, and the drive circuit is fixed to a substrate made of a conductive material with one terminal electrically connected to the semiconductor element. An engine starting/power generation device characterized in that one terminal of the semiconductor element is connected to a battery or the stator coil via the substrate, and a substrate of the drive circuit is supported by the partition member. (4) the partition member separates a circuit chamber in which the drive circuit is accommodated from a mechanism chamber in which the stator coil is accommodated;
4. The engine starting/power generation device according to claim 3, further comprising a power generation system electric circuit connected to said stator coil arranged in said mechanism chamber.