FR3062885A1 - STARTER - Google Patents

Abstract

An object of the present invention is to obtain a starter which allows the starting of an engine without causing a momentary interruption in electrical equipment or electronic equipment, with a simple structure, without considerable starter frame and without power reduction. starter output. A short circuit switch (5) which is connected in parallel with an inductor coil (1b) and bypasses the inductor coil (1b) has a short circuit switch contact (5a) connected in series between a switch an armature (5b) having an end connected between the inductor coil (1b) and the armature (1a) and the other end connected to the ground, and causing a movable contact of the short circuit switch contact (5a), and a piston (5c) fixed to the movable contact of the short circuit switch contact (5a).

Description

Field of the invention

The present invention relates to a starter which starts, for example, the engine of a vehicle.

Description of Related Art

To start an engine using a conventional starter of the electromagnetic thrust type, a coil of a start switch is energized and an internal contact of the start switch is closed, to supply power to a battery. to a motor and generate a torque in the armature of the motor. After that, the armature's rotational force is transmitted to an engine crankshaft via a pinion and an engine crown which are meshed with each other, as a result of which the engine is started.

When the start switch is closed, the armature is still stationary, and no counter-electromotive force is generated, as a result, an inrush current of several hundred to a thousand and several hundred amperes flows. because of the extremely small internal resistance of the starter. The internal specific resistance of the battery then gives rise to a decrease in the terminal voltage, and a voltage drop occurs.

A problem therefore arises because the voltage drop described above in the battery causes momentary interruptions when other electrical and electronic equipment of the

JCI-P vehicles, for example audio, navigation systems, electronic control units (ECUs) and the like are used during engine starting.

Such momentary interruptions are not particularly problematic during starting of the ordinary engine, but there is a problem of discomfort caused to the driver and passengers, for example in vehicles provided with an idling stop function, due the appearance of a momentary interruption during a restart after an idle stop. Therefore, steps are taken to prevent battery voltage drops by providing standby power or by installing a step-up DC / DC converter to prevent such momentary interruptions.

In order to avoid momentary interruptions, certain known starters are provided with an electromagnetic switch which opens and closes a main contact arranged in a motor circuit, with a current cancellation resistor connected in series with the main contact in the circuit. motor, a short-circuit relay arranged so as to be able to short-circuit the current-canceling resistor, and a timer circuit intended to delay the operation of the short-circuit relay (see for example the publication of Japanese patent application no. 2009-287,459).

When the main contact of this starter closes, current flows from the battery to the motor via the current cancellation resistor. A voltage lower than the total battery voltage is

JCI-P applied at this time to the motor, and as a result a starter current, that is to say a motor inrush current is reduced. After a predetermined time has elapsed, a short-circuit relay energizing coil is energized, the current canceling resistor is short-circuited, and the total battery voltage is applied to the motor. This allows the engine to be started without momentary interruptions.

In order to avoid momentary interruptions, starters are also known which are provided with: a start switch connected in series between a battery and a motor, a current canceling resistor connected in series with the start switch , a short circuit switch connected in parallel to the current canceling resistor, for short-circuiting the current canceling resistor, and a control circuit which controls the opening and closing of the short-circuit (see for example Japanese patent application publication No. 2011-94555).

When the start switch of this starter closes, current flows from the battery to the motor via the current cancellation resistor. A voltage lower than the total battery voltage is applied to the motor at this time, and as a result the starter current, i.e. the inrush current of the motor, is reduced. After a predetermined time has elapsed, the current canceling resistor is short-circuited by closing the short-circuit switch, and the total voltage

JCI-P from the battery is applied to the engine. This allows the engine to start without momentary interruptions.

In order to avoid momentary interruptions, starters are also known which are provided with both a permanent magnet and an induction coil in a portion of the induction system of the motor (see for example the publication of Japanese patent application no. ° 2016-46906). In this starter, when the contact closes, a current flows from the battery to the motor via the induction coil, as a result of which the starter current, i.e. the inrush current of the motor is reduced . The field coil is short-circuited after a predetermined time has passed. This allows the engine to start without momentary interruptions.

However, the starter disclosed in Japanese Patent Application Publication No. 2009-287459 requires a current cancellation resistor and a timer circuit, and therefore uses a complex structure and a substantial starter frame, all of which are problematic. In addition, the starter disclosed in Japanese Patent Application Publication No. 2009-287459 employs a timer circuit, and the problem therefore arises that when the engine friction torque is high, for example at low temperatures, the speed of motor rotation does not rise and a predefined counterelectromotive force is not exceeded even after a predetermined period and the inrush current after short-circuiting of the current cancellation resistor

JCI-P is important. The occurrence of a momentary interruption therefore becomes troublesome.

In the starter disclosed in Japanese patent application publication No. 2011-94555, the heat capacity of the current canceling resistor is small, and the shorting time of the current canceling resistor is restricted. Subsequently, there is the problem of an increased inrush current after short-circuiting of the current-canceling resistor, and the problem of the occurrence of a momentary interruption, when a predefined counter-electromotive force is not not exceeded after a predetermined time has passed. This is problematic because, consequently, the starter frame is made more considerable in order to ensure the heat capacity of the current suppression resistor.

Starters in both Japanese Patent Application Publication No. 2009-287459 and Japanese Patent Application Publication No. 2011-94555 use a current cancellation resistor, and are therefore problematic in terms of the increased internal resistance of the starter and reduced starter output power.

The starter disclosed in Japanese Patent Application Publication No. 2016-46906 requires a field coil current control unit which interrupts a short circuit of the field coil by controlling the current flowing in the field coil. The structure involved is therefore complex, which is problematic.

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Summary of the invention in equipment

An object of the present invention, achieved in order to solve the above problems, is therefore to obtain a starter which allows the starting of an engine without causing momentary interruption of electrical or electronic equipment, with a simple structure, without considerable starter frame and without reduction of the starter output power.

A starter according to the present invention is provided with: an armature of a motor; a battery which supplies power to the armature; a start switch connected in series between the battery and the armature; an induction coil which is connected in series to the armature and generates a magnetic flux in the armature; and a short circuit switch which is connected in parallel to the field coil and short circuits the field coil, wherein the short circuit switch has a short circuit switch contact connected in series between the start switch and armature, a drive coil which has one end connected between the field coil and the armature and the other end connected to ground, and which causes a movable contact of the short switch contact -circuit, and a piston fixed to the movable contact of the short-circuit switch contact, the short-circuit switch being configured so that the piston is driven and the short-circuit switch contact is closed when a voltage applied to the drive coil becomes higher than a fixed voltage

JCI-P beforehand due to a counterelectromotive force which is generated as a result of the rotation of the armature when the start switch is closed.

In the starter according to the present invention, the short-circuit switch which is connected in parallel to the field coil and short-circuits the field coil comprises: the short-circuit switch contact connected in series between the circuit breaker start-up and armature, the drive coil which has one end connected between the induction coil and the armature and the other end connected to ground, and which drives a movable contact of the short-circuit switch contact, and the piston fixed to the movable contact of the short circuit switch contact, the short circuit switch being configured so that the piston is driven and the short circuit switch contact is closed when a voltage applied to the coil due to a counter-electromotive force which is generated as a result of the rotation of the armature when the switch closes r starting.

As a result, it becomes impossible to start an engine without causing a momentary interruption in electrical or electronic equipment, with a simple structure without considerable starter frame and without reduction of the starter output power.

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Brief description of the drawings

Other characteristics and advantages of the invention will emerge more clearly on reading the description below, given with reference to the appended drawings, in which:

Figure 1 is a circuit diagram illustrating a starter according to an embodiment 1 of the present invention;

Fig. 2 is a graph illustrating current and voltage waveforms of the starter according to embodiment 1 of the present invention; and Figure 3 is a circuit diagram illustrating another starter according to embodiment 1 of the present invention.

Description of the preferred embodiments

Preferred embodiments of the starter according to the present invention will be explained below with reference to the accompanying drawings. Identical or corresponding portions in the figures will be designated by identical reference symbols.

Embodiment 1

FIG. 1 is a circuit diagram illustrating a starter according to embodiment 1 of the present invention. In FIG. 1, a starter 10 comprises an armature 1a of a motor 1, a battery 2 which supplies power to the armature 1a, a start switch 3 connected to the battery 2, a start switch 4 connected at series between the battery 2 and the armature la: an inductor lb being a

JCI-P portion of inductor system and connected in series to the armature la, and a short circuit switch 5 which is connected in parallel to the inductor lb and short-circuits the inductor lb.

The motor 1, which is a motor intended to start a heat engine not shown, has the armature 1a and the induction coil 1b described above, and also a portion of the induction system 1c which generates a magnetic flux as a result of a excitation by battery 2 or by another power source.

The start switch 4 consists of a start switch contact 4a which is a normally open contact which is connected in series between the battery 2 and the armature la, of a drive coil 4b intended to drive a movable contact of a start switch contact 4a, of a holding coil 4c which maintains the movable contact of the start switch contact 4a in a contact position with a fixed contact, and of a piston 4d which is fixed to the movable contact of the start switch contact 4a. One end of the holding coil 4c is connected to the start switch 3, and the other end is connected to ground.

The short-circuit switch 5 consists of a short-circuit switch contact 5a which is a normally open contact which is connected in series between the start switch contact 4a and the armature la, d ' a drive coil 5b intended to cause a movable contact of the short-circuit switch contact 5a, and of a piston 5c fixed to the contact

JCI-P mobileο mobile from short-circuit switch contact 5a. One end of the drive coil 5b is connected between the inductor lb and the armature la, and the other end is connected to ground.

The operation of the starter 10 having the above configuration will be explained below with reference to FIG. 2. FIG. 2 is a graph illustrating current and voltage waveforms of the starter according to embodiment 1 of the present invention. In FIG. 2, the vertical axis represents the electrical supply voltage of the battery 2 and the starter current flowing in the armature la, and the horizontal axis represents time.

In a first step of starting the engine, the start switch 3 is closed according to a request to start the engine, at time Tl, whereupon a current la begins to flow from the battery 2 to the armature la, via the start switch 3, the drive coil 4b and the field coil lb. A current also flows there from the battery 2 to the holding coil 4c via the start switch 3. Then, in a second step, the driving coil 4b is excited, as a result of which the piston 4d is driven and the start switch contact 4a is closed at time T2. The holding coil 4c is also excited and therefore the piston 4d is held in position, and the

short circuit in the contact switch of start-up 4a is preserved. By the closing of contact switch of start-up 4a, The induced receives a diet at

JCI-P direct current from battery 2, and generates a torque accordingly, whereupon a pinion coupled to an armature shaft via a freewheel clutch moves towards a crown formed on the engine crankshaft, and meshes with the crown.

When the start switch contact 4a is closed, the current flowing from the battery 2 to the drive coil 4b practically disappears, and a current lb flows from the battery 2 to the start switch contact 4a closed, at the inductor lb and to the armature la. As a result of this, the rotational force of the armature la is transmitted to the crankshaft of the engine, and starting of the engine is initiated.

In a third step, then, the short-circuit switch contact 5a is closed at time T3 after a preset time has elapsed since the moment when the start switch contact 4a was closed. Specifically, the piston 5c is driven and the short circuit switch contact 5a is closed when the voltage applied to the drive coil 5b becomes higher than a previously set voltage due to the action of a force against -electromotive which is generated as a result of the rotation of the armature la and which increases with increasing turns of the armature la.

By closing the short-circuit switch contact 5a, a current flows from the battery 2 to the armature la via the start switch contact 4a and the short-circuit switch contact 5a. Here the short switch contact 3062885

JCI-P circuit 5a is closed and the inductor lb is short-circuited, and therefore the starter current increases again, as illustrated in Figure 2.

By the short circuit of the induction coil 1b, moreover, the means for generating a magnetic flux in the armature 1a now includes the portion of the induction system only. After the engine start has been initiated, the engine start is completed at time T4.

The short-circuit switch 5 operates in accordance with the voltage which is applied to one end of the drive coil 5b, due to the action of the electromotive force, hence the absence of complex control involving the use of a rotation detection sensor, a timer circuit or the like in the motor 1, which contributes to simplifying the structure. The timing of the short circuit and the degree of voltage drop at the time of the short circuit can be adjusted by changing the voltage at which the short circuit switch contact 5a is closed, i.e. the voltage at which the piston 5c is driven.

Here, a starter current II designates the inrush current flowing in the armature la at time T2 at which the start switch contact 4a is closed. The starter current II is given by the expression (1) below, where V0 denotes the voltage of the battery 2, RB denotes the internal specific resistance of the battery 2, RF denotes the resistance of the induction coil lb, RM designates the internal resistance of the armature la, and RW designates the resistance of the wiring.

JCI-P = V0 / (RB + RF + RM + RW) ... (1)

In addition, a starter current 12 designates the current flowing in the armature at time T3 at which the short-circuit switch contact 5a is closed. A counter-electromotive force E is generated in the armature as a result of the armature rotation la, since a current flows in the armature la before time T3. The starter current 12 is given by expression (2) using the internal specific resistance RB of the battery 2, the internal resistance RM of the armature la, and the resistance of the wiring RW.

= (V0-E) / (RB + RW + RM) ... (2)

The counter-electromotive force E is given by expression (3) below, where k denotes a motor constant, Φ denotes an amount of magnetic flux, and n denotes the speed of rotation of the motor. The starter current 12 flowing in the armature can be adjusted by modifying engine specifications.

E = k x Φ x n ... (3)

When the voltage at which the short-circuit switch contact 5a becomes closed is set high, the field coil 1b is not short-circuited until the counterelectromotive force E generated in the armature is high. Given the high electromotive force E, specifically, the relation II> 12 is checked according to expression (2), and the short-circuit switch contact 5a becomes closed at a point where the speed of rotation of the motor is high, according to expression (3). As a result, starting the engine

JCI-P takes time because of the period of time until the inductor coil 1b is short-circuited, that is to say because of the lengthening of the period of time T2 to time T3.

Consequently, a voltage is fixed at which the short-circuit switch contact 5a is closed, so that the starter current II and the starter current 12 are equal, as illustrated in FIG. 2, consequently , the period of time until the short-circuit switch contact 5a is closed and the inductor coil 1b is short-circuited, and it becomes possible to start the engine quickly while eliminating a momentary interruption.

Consequently, the drive coil 4b of the start switch 4, the induction coil lb and the resistance of the wiring are present in the circuit during the first step, the induction coil lb and the resistance of the wiring are present during the second step, and the resistance of the wiring alone is present during the third step. Consequently, the electrical resistance decreases in three stages, from the first stage to the third stage.

By using the inductor lb here as a current cancellation resistor, there is no need to separately establish a current cancellation resistor, and it becomes possible to simplify the structure and reduce the scale of the framework of the starter, and achieve weight and cost reductions. The current is suppressed by the generation of the counterelectromotive force, because the armature turns it

JCI-P because of the current la and the current lb occurring before the third stage.

In addition, the motor can be started quickly and reliably also during a high load when the engine friction torque is high, for example at low temperatures, since it generates a greater torque than when a suppression resistor current is used.

The current flowing in the induction coil lb can be reduced, and the magnetic flux inductor can likewise be reduced, by a short-circuiting of the induction coil lb by the short-circuit switch 5. Consequently, the characteristic of the starter switches the torque type to rotation type, and the engine can be started quickly. This allows a reduction in the operating time of the starter 10 and increases comfort. In addition, the current consumption can be reduced and the efficiency increased since the loss in copper derived from the inductor 1b is small.

In the starter 10, the induction coil lb connected between the battery 2 and the armature la is first excited during the starting of the engine, and after a period of time which is fixed beforehand, the current flowing in the induction coil lb is reduced by the short circuit switch 5. As a result, an initial inrush current is reduced and a voltage drop is suppressed, and it becomes possible to start the engine efficiently without giving rise to momentary equipment interruptions electric or similar.

JCI-P

In embodiment 1, thus, a short-circuit switch which is connected in parallel to an inductor and short-circuits the latter has: a short-circuit switch contact connected in series between the start switch and the armature, a drive coil which has one end connected between the field coil and the armature and the other end connected to ground and which causes a movable contact of the short circuit switch contact, and a piston fixed to the movable contact of the short-circuit switch contact, the short-circuit switch being configured so that the piston is driven and the short-circuit switch contact is closed when a voltage is applied to the coil. drive becomes higher than a pre-set voltage due to a counter-electromotive force which is generated as a result of the rotation of the armature when the start switch is closed e.

Consequently, it becomes possible to start an engine without causing a momentary interruption in electrical or electronic equipment, with a simple structure, without considerable starter framework and without reduction of the starter output power.

Instead of the portion of the inductor system illustrated in FIG. 1 which generates a magnetic flux in the armature la in embodiment 1, a permanent magnet ld can be provided which generates a magnetic flux in a similar manner to the portion of inductor system, as shown in Figure 3.

JCI-P

In FIG. 3, for example the magnetic poles of the portion of the inductor system consist of a plurality of N poles and matched S poles, where first poles are configured by the inductor 1b and second poles are configured by the permanent magnet ld. A motor 1 comprising both the inductor lb and the permanent magnet ld also induces the effect of suppressing voltage drops, and allows the engine to start more efficiently without giving rise to a momentary interruption in electrical or similar equipment. .

Specifically, the mechanical resistance of the induction system during excitation of the induction coil lb is increased, and the motor torque is likewise increased, thanks to the particularity of having both the induction coil lb and the permanent magnet available. ld. Consequently, the engine can also be reliably started when the engine friction torque is high, for example at low temperatures.

In a low load region where the load is limited and the motor rotation speed is high, the magnetic flux of the inductor system decreases and a large rotation is caused by a stop or a limitation, by the short-circuit switch 5 , of the current with which the induction coil lb is excited. This allows for a quick start. As a result, the operating time of the starter 10 can be shortened and the comfort increased. It is also possible to suppress excessive increases in

S63317 EN JCI-P the engine speed at zero load, and extend the life of the starter 10.

JCI-P

Claims (5)

1. Starter, characterized in that it comprises: an armature (la) of a motor (1); a battery (2) which supplies power to the armature (la); a start switch connected in series between the battery (2) and the armature (la); an induction coil (lb) which is connected in series to the armature (la) and generates a magnetic flux in the armature (la); and a short circuit switch (5) which is connected in parallel to the field coil (lb) and short-circuits the field coil (lb), wherein the short circuit switch (5) has a contact short circuit switch (5a) connected in series between the start switch and the armature (la), a drive coil (5b) which has one end connected between the induction coil (lb) and the armature ( la) and the other end connected to ground, and which causes a movable contact of the short-circuit switch contact (5a), and a piston (5c) fixed to the movable contact of the short-circuit switch contact (5a), the short circuit switch (5) being configured so that the piston (5c) is driven and the short circuit switch contact (5a) is closed when a voltage applied to the coil d drive (5b) becomes higher than a pre-set voltage due to a counterelectromotive force which is generated due to rotation S63317 EN JCI-P of the armature (la) when the start switch is closed. 2. Starter according to claim 1, 5 characterized in that the voltage necessary for an operation of the short-circuit switch (5) is fixed in such a way that a starter current which flows in the armature (la) at the moment of the excitation of the induced by the coil 10 inductor (lb) is equal to the starter current flowing in the armature (la) at the time of excitation of the armature (la) by a short circuit of the inductor coil (lb) by the switch short circuit (5). 3. Starter according to claim 1 or 2, characterized in that it further comprises, in addition to the induction coil (lb), a permanent magnet which generates a magnetic flux in the armature (la). 1/3 S63317 FR JCI-P