JP2002054539A - Starter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a starter to be decreased in size and weight and a cost as a motor is pre-rotated and a pinion can be fitted in a ring gear. SOLUTION: In the starter, a stater 5 of a DC motor 1 has a series winding field coil 2 formed that main coils 21 wound around three single poles and subcoils wound around three single poles are interconnected in parallel with each other. When a key switch K is closed, the subcoils 22 are electrically energized through a relay 3 and the main coils 21 are also weakly electrically energized. Thereby, the DC motor 1 is weakly electrically energized before a pinion 9 makes contact with a ring gear R and pre-rotated before the pinion 9 makes contact with the ring gear and is smoothly engaged with the ring gear R. When a main contact 44 is closed, the main coils 21 are charged with a large current, the pinion 9 is driven by a full-power and an engine is brought into a starting state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention belongs to the technical field of an engine starter for starting an internal combustion engine such as a reciprocating engine.

[0002]

2. Description of the Related Art Usually, a starter cranks and starts an engine by inserting a pinion into a ring gear of an engine and driving the pinion to rotate. At this time, it is desirable that the pinion be rotated slowly to some extent before the pinion comes into contact with the ring gear so that the pinion can easily fit into the ring gear so that the teeth of the pinion can be smoothly fitted into the teeth of the ring gear. Therefore, there is a conventional starter in which when the key switch is closed, the starter motor slowly starts preliminary rotation first, and the starter motor rotates with full force after the pinion is fitted to the ring gear.

[0003] For example, as prior art 1, Japanese Utility Model Laid-Open No. 3-4
Japanese Patent No. 5074 discloses a starter motor having a starter motor in which some of the magnetic poles of the stator are permanent magnets and the other magnetic poles have a field coil, and a magnet switch that energizes the field coil only when the plunger is retracted. Is disclosed. According to this starter, when the key switch is closed, first, the starter motor slowly starts to rotate due to the weak magnetic field generated only by the permanent magnet. Then, when the pinion is fitted to the ring gear, the contacts of the magnet switch are closed, so that the field coil is energized and a strong field is obtained,
The starter motor rotates at full power.

[0004] However, in this starter, a permanent magnet and a field coil are used in combination for the field of the stator.
The field created by the permanent magnet is weak, and the output of the starter motor does not increase so much even at full power. Therefore, if a sufficient motor output is to be obtained, the size of the starter motor becomes large, the weight and volume of the starter increase, and the starter must be expensive.

On the other hand, Japanese Patent Laid-Open Publication No.
No. 344 has a starter motor in which the field of the stator is formed only by permanent magnets, and a relay that passes a relatively small current through the armature through the resistance element until the pinion is fitted to the ring gear. A starter is disclosed. According to this starter, when the key switch is closed,
First, the armature is slightly energized via the resistance element, and the starter motor starts to rotate slowly. Then, when the pinion is fitted to the ring gear, the contact point of the magnet switch closes, a large current flows through the armature, and the starter motor rotates at full power.

However, in this starter, since the field of the stator is formed by the permanent magnet, the field is weak, and the output of the starter motor does not increase so much even at full power. Therefore, in order to obtain sufficient motor output, the size of the starter motor becomes large, and the weight and volume of the starter increase.Because a strong permanent magnet is expensive, the price of the starter also increases. There is a disadvantage that it has to be done.

In any of the prior arts, when the power supply to the starter is stopped after the engine is started, the starter motor is short-circuited, the brake is applied by the back electromotive force, and the armature stops immediately. I have.

[0008]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a starter that is smaller, lighter and less expensive than any of the above-mentioned prior arts, while allowing the motor to rotate preliminarily and fitting the pinion to the ring gear. Is a problem to be solved.

Further, in the starter provided by the present invention, it is desirable that the preliminary rotation torque is high and the pinion engagement with the ring gear is improved. Further, it is desirable that after the engine is started, there is a braking action by the back electromotive force so that the inertial rotation of the armature can be stopped immediately.

[0010]

In order to solve the above problems, the inventor has invented the following means.

(First Means) A first means of the present invention is a starter according to claim 1. That is, the stator of the DC motor has a series wound field coil in which a plurality of main coils and a plurality of sub-coils are connected in parallel with each other. Here, the sub coil is an auxiliary field coil that is energized via a relay prior to the main coil when the key switch is closed. On the other hand, the main coil is a main field coil that is energized through a magnet switch that closes after the relay is closed.

[0012] Further, the manner of connecting the plurality of sub-coils to each other is not limited, and the manner of connecting the plurality of main coils to each other is not limited. For example, if the stator has eight salient poles, a main coil is wound around every other four poles and a sub coil is wound around the remaining four poles.
They may be connected in series.

According to the present invention, when the key switch K is closed, the relay is first closed to energize the sub-coil and the armature connected in series with each other, and the DC motor starts preliminary rotation. Then, while the pinion is protruded toward the ring gear by the magnet switch, the pinion is driven relatively slowly by the DC motor. Therefore, since the pinion comes into contact with the ring gear while being pre-rotated, the pinion can mesh with the ring gear without much impact.

Here, the field coil acting before the pinion meshes with the ring gear is a sub coil,
Subcoils are usually relatively resistant. Therefore, an electromagnetic torque sufficient for the preliminary rotation is generated between the sub-coil and the armature even if only a small current flows. That is, during the pre-rotation, a stronger rotation torque is generated and the pinion is pre-rotated sufficiently powerfully as compared with the conventional technique using a permanent magnet as the field magnet, so that the meshing property of the pinion with the ring gear is improved.

Next, the magnet switch is closed with an appropriate delay before the relay is closed, and a large current is normally supplied to the armature through the main coil having a relatively small resistance. Then, a large current is supplied to the main coil in addition to the sub-coil already supplied with electric power via the relay, so that a strong field is formed. Not only that, since the sub coil and the main coil are connected in parallel with each other,
The armature is energized not only with the large current of the main coil but also with the current of the sub coil, and the armature is driven with a large torque. Then, since the pinion has already meshed with the ring gear, the pinion drives the ring gear to rotate with full force without any meshing impact, and the engine is cranked and started.

Thereafter, when the key switch is opened, the relay follows and returns, and both ends of the sub coil are short-circuited via the armature. Then, the electromagnetic braking is applied to the DC motor by the back electromotive force, so that when the key switch is opened, the armature immediately stops its rotation.

In the above operation, the starter according to the present invention does not require a permanent magnet as a field magnet, so that the cost and the size and weight can be reduced by using no expensive and bulky permanent magnet.

Therefore, according to the starter of this means,
While the motor can be pre-rotated to fit the pinion into the ring gear, it is possible to provide a smaller, lighter and cheaper than any of the above-mentioned prior arts.

Further, according to the starter of this means, there is an effect that the preliminary rotation torque is high as described above, and the meshing property of the pinion with the ring gear is improved. Further, after the engine is started, a braking effect by the back electromotive force is obtained, and there is an effect that the inertial rotation of the armature can be stopped immediately. In addition, since the sub-coil naturally has a higher resistance than the main coil, a relatively small current flows through the relay that energizes the sub-coil, so that there is also an effect that the contacts of the relay are prevented from welding.

(Second Means) A second means of the present invention is a starter according to claim 2. That is, in the stator of the DC motor, the main coil and the sub coil forming the series-wound field coil form unit poles adjacent to each other.

In this means, a known starter motor (JP-A-5-141332 and Japanese Utility Model Publication No. 4-41741) is used.
Unlike the above-mentioned publication, a series-wound coil is not wound on each salient pole of the stator after a series-wound coil is wound on it. Rather, the main coil and the subcoil of the present means are both series-wound field coils connected in series to the armature.

In addition, in the starter of the present means, the main coil and the sub coil are wound around salient poles which are separate from each other, and form unit poles adjacent to each other. Therefore, the winding of the main coil and the winding of the sub-coil may be performed in any order, and the structure of the stator is simplified by not winding each salient pole doubly, thereby reducing cost. Also.

Therefore, according to the starter of this means,
In addition to the effect of the first means described above, a further cost reduction effect can be obtained.

(Third Means) A third means of the present invention is a starter according to claim 3. That is, the stator of the DC motor has a series-wound field coil in which a plurality of main coils and a plurality of sub-coils are connected in parallel with each other.

In this means, the main coil and the sub coil are connected in parallel to each other to form a series wound field coil (a field coil connected in series to the armature). Therefore, in the preliminary rotation state until the pinion meshes with the ring gear, the main coil is not energized,
The armature can be energized through only the subcoil (by a key switch or relay) to obtain a moderate amount of rotational torque. Then, when the magnet switch is closed and the main coil is energized, a large current flows to the armature through the main coil, so that the DC motor exerts a sufficiently large rotating torque.

In this means, for example, the main coil may be composed of a plurality of coils connected in parallel with each other, while the sub coil may be composed of a plurality of coils connected in series with each other. Then, even if the main coil and the sub-coil are each wound around a single pole with conductors of the same wire diameter, the resistance of the sub-coil naturally becomes larger than the resistance of the main coil, and only a relatively small current flows through the sub-coil. Absent. Therefore,
Key switches and relay contacts that energize the sub coil
Failures such as fusing due to excessive current are prevented.

In the above operation, since the starter of the present invention does not require a permanent magnet as a field magnet, the cost can be reduced and the size and weight can be reduced by using no expensive and bulky permanent magnet.

Therefore, according to the starter of this means,
While the motor can be pre-rotated to fit the pinion into the ring gear, it is possible to provide a smaller, lighter and cheaper than any of the above-mentioned prior arts.

[0029]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the starter of the present invention will be more clearly and fully described in the following examples so that those skilled in the art can understand the present invention.

Embodiment 1 (Structure of Embodiment 1) As shown in FIG. 1, a starter according to Embodiment 1 of the present invention includes a pinion 9, a DC motor 1, a relay 3, and a magnet as main components. It has a switch 4.

The pinion 9 is attached to the distal end of the DC motor 1 via a one-way clutch 8. When the magnet switch 4 is actuated, the pinion 9 is pushed out via the drive lever 7, protrudes and fits into the ring gear R of the engine. , And has a function of driving the ring gear R to rotate.

The DC motor 1 includes a stator 5 and an armature 6
And a starter motor for driving the pinion 9 to rotate. The configuration of the stator 5 of the DC motor 1 will be described later in detail.

The relay 3 has fixed contacts 33 and 34 that are closed following the key switch K, and has a function of supplying power to the DC motor 1 through the fixed contacts 33 and 34 in an auxiliary manner. The key switch K has normally closed contacts 31 and 32, and short-circuits a part of the field coil 2 (sub coil 22) and the armature 6 when the key switch K is open.

The magnet switch 4 has a solenoid coil 40, a plunger 43 attracted by the solenoid coil 40, and a main contact 44 closed by the plunger 43. The solenoid coil 40 includes a suction coil 41 and a holding coil 42. The holding coil 42 is directly grounded, but the suction coil 41 is connected to one end of a part of the field coil (the main coil 21). Therefore, the main contact 4 is still energized while the suction coil 41 is energized.
While the shutter 4 is not closed, the main coil 21 and the armature 6 are preliminarily energized via the suction coil 41. On the other hand, the main contact 44 is a pair of fixed contacts 4.
5 and 46 and a movable contact 47 held at the rear end of the plunger 43. And the magnet switch 4
When the plunger 43 is attracted and moved by the solenoid coil 40 and the main contact 44 is closed, a large current flows from the battery B to the main coil 21 and the armature 6 of the DC motor 1. That is, the magnet switch 4
Makes the pinion 9 protrude, and the pinion 9
, The main contact 44 is closed and has a function of supplying a large current to the DC motor 1.

The stator 5 of the DC motor 1 has a series winding field in which three main coils 21 connected in parallel with each other and three sub-coils 22 connected in series with each other are connected in parallel with each other. It has a coil 2. Here, the sub coil 22 is an auxiliary field coil that is energized via the relay 3 prior to the main coil 21 when the key switch K is closed. On the other hand, the main coil 21 is a main field coil that is energized via the magnet switch 4 that closes after the relay 3 closes.

That is, unlike a normal series-wound winding motor, a series-wound coil is not wound on each salient pole 51 of the stator 5 and then a winding coil is wound. Instead, the main coil 21 (three in parallel) and the sub coil 22 (three in series) are series wound field coils connected in series to the armature 6.

In the stator 5 of the DC motor 1, as shown in FIG.
And the sub-coil 22 form unit poles adjacent to each other. That is, the inner peripheral surface of the yoke 52
Six salient poles 51 are fixed every 0 °, and each salient pole 51 is fixed.
, A main coil 21 and a sub coil 22 are wound alternately. Here, in the main coil 21, a rectangular wire having a large cross-sectional area is wound so as to withstand a large current, while in the sub-coil 22, a conductor having a circular cross-section having a relatively small cross-sectional area is wound in a solenoid coil shape. Is equipped.

Therefore, the main coil 21 and the sub coil 22 are wound around the salient poles 51 which are separate from each other, and form the unit poles adjacent to each other. As a result, the winding step of the main coil 21 and the winding step of the sub coil 22 may be performed in any order, and the configuration of the stator 5 is reduced by the amount that each salient pole 51 is not wound twice. Simplification and cost reduction are achieved.

(Operation and Effect of First Embodiment) The starter of this embodiment is configured as described above, and thus exhibits the following operation and effect.

First, when the key switch K is closed, the solenoid coil 40 of the magnet switch 4 is energized, and the plunger 43 starts to be attracted.
Operates.

At this time, since the attraction coil 41 of the solenoid coil 40 is connected to one end of the main coil 21 as described above, the electric current applied to the attraction coil 41 is not applied to the main coil 21 which is parallel to the electric coil. It flows to the ground through the child 6. The current at this time is largely limited by the resistance of the suction coil 41, and flows only slightly. Therefore, the main coil 21 generates a weak field, and the armature 6
Obtains auxiliary rotational drive torque.

In parallel with this, the fixed contact 3 of the relay 3
3 and 34 are closed, and the three sub-coils 22 and the armature 6 connected in series are energized, and a relatively weak rotational torque is generated in the armature 6.

That is, since the main coil 21 is weakly excited via the attraction coil 41 and the sub-coil 22 is also excited via the relay 3, a rotational torque is generated in the armature 6 and the DC motor 1 Start. Then, the pinion 9 is relatively slowly driven by the DC motor 1 while being protruded toward the ring gear R by the magnet switch 4. Therefore, since the pinion 9 comes into contact with the ring gear R while rotating preliminarily, the pinion 9 and the ring gear R can mesh with each other without much impact.

Here, before the pinion 9 meshes with the ring gear R, both the main coil 21 and the sub coil 22 are excited as described above. However, since the main coil 21 passes through the attraction coil 41, a large current does not flow yet, and the main coil 21 is excited only weakly. On the other hand, the sub-coil 22 is energized through the relay 3 as described above. However, the sub-coil 22 has a larger number of turns of the conductor than the main coil 21 and has a longer conductor and a smaller cross-sectional area. , Three are connected in series with one another. Therefore, even if a relatively small current flows through the sub-coil 22, a sufficient electromagnetic torque for the preliminary rotation is generated between the sub-coil 22 and the armature 6.

That is, at the time of the preliminary rotation, the main coil 2 is compared with the prior art in which a permanent magnet is used for the field magnet 2.
Since both 1 and the sub-coil 22 are excited, a stronger rotating torque is generated. As a result, since the pinion 9 is preliminarily rotated with a sufficiently strong torque, the pinion 9 quickly meshes with the ring gear, and the meshing property of the pinion 9 with the ring gear R is improved.

Next, the magnet switch 4 is closed with an appropriate delay before the relay 3 is closed, and the armature 6 is connected directly to the armature 6 through the main coil 21 having a relatively small resistance without passing through the attraction coil 41 through the main contact 44. Is supplied with a large current.
Then, a large current is applied to the main coil 21 in addition to the sub-coil 22 already energized via the relay 3, so that a strong field is formed. Not only that, since the sub coil 22 and the main coil 21 are connected in parallel with each other, the armature 6 includes the main coil 21.
And the current of the sub-coil 22 is also supplied, and the armature 6 is driven with a large torque. Then, since the pinion 9 has already meshed with the ring gear R, the pinion 9 rotates the ring gear R with full force without any meshing impact, and the engine (not shown) is cranked and started.

Thereafter, when the key switch K is opened, the magnet switch 4 returns, the main contact 44 is opened, and the power supply to the main coil 21 is stopped. In parallel with this, the relay 3 is driven by the key switch K to return, the energization of the sub coil 22 is stopped, and the normally closed contacts 31, 32
Is closed, and both ends of the sub coil 22 are short-circuited via the armature 6. Then, the electromagnetic braking is applied to the DC motor 1 by the back electromotive force. Therefore, when the key switch K is opened, the rotation of the armature 6 is stopped immediately.

In the above operation, the starter of this embodiment does not require a permanent magnet as the field magnet 2, so that the cost and the size and weight can be reduced by using no expensive and bulky permanent magnet. Further, since the main coil 21 and the sub-coil 22 each form a single pole alternately as described above, the number of windings is reduced in the winding process as compared with a configuration in which the main coil 21 is superimposed on the sub-coil 22 and wound. , Resulting in cost reduction.

Therefore, according to the starter of this embodiment, the pinion 9 can be smoothly engaged with the ring gear R by pre-rotating the DC motor 1, but it is smaller, lighter and cheaper than any of the above-mentioned prior arts. There is an effect that can be.

According to the starter of this embodiment, as described above, both the main coil 2 and the sub coil 22 are energized before the main contact 44 of the magnet switch 4 is closed. There is an effect that the engagement of the pinion 9 with the ring gear R is improved. At the same time, even after the main contact 44 is closed, since not only the main coil 21 but also the sub coil 22 is energized, the driving torque of the DC motor 1 increases, and the engine can be started more easily. There is.

Further, after the engine is started, the key switch K
Is opened, a braking action by the back electromotive force is obtained, and there is also an effect that the inertial rotation of the armature can be stopped immediately.
Not only that, the resistance of the sub-coil 22 naturally becomes higher than that of the main coil 21.
Only a relatively small current flows through the relay 3 that energizes the relay 2, and there is an effect that welding of the contacts of the relay 3 is prevented.

(Modification 1 of Embodiment 1) As a modification 1 of this embodiment, it is possible to implement a starter that does not have the relay 3 and energizes the sub-coil 22 via the key switch K. In this modification, although the electromagnetic braking action cannot be obtained, there is an effect that the size and weight can be reduced and the cost can be reduced as compared with the first embodiment because the relay 3 is not provided.

(Modification 2 of Embodiment 1) As a modification 2 of this embodiment, it is possible to implement a starter in which the fixed contact 46 of the magnet switch 4 is grounded. In the present modification, the main coil 21 is not excited via the suction coil 41 before the main contact 44 is closed.
Although the preliminary driving torque is reduced, the operation and effect equivalent to the first embodiment can be obtained if a sufficient field can be obtained with the sub coil 22. If a relay 3 that can withstand a relatively large current is employed, a configuration in which three sub-coils 22 are connected in parallel with each other may be adopted, so that the preliminary driving torque can be increased to some extent.

(Modification 3 of Embodiment 1) As a modification 3 of the present embodiment, a starter in which the main coil 21 and the sub-coil 22 forming each single pole of the stator 5 are formed of the same standard winding. Is also possible. According to this modification, in addition to the effect similar to the effect of the above-described first embodiment, since the winding step of the main coil 21 and the sub coil 22 can be performed at one time, there is an effect that the cost can be further reduced.

[Brief description of the drawings]

FIG. 1 is a circuit diagram illustrating a configuration of a starter according to a first embodiment.

FIG. 2 is an end view showing a configuration of a field magnet according to the first embodiment.

[Explanation of symbols]

3: Relay 31, 32: normally closed contact 33, 34: fixed contact 4: magnet switch 40: solenoid coil 41: suction coil 42: holding coil 43: plunger 44: main contact 45, 46: fixed contact 47: movable contact 1 : DC motor 5: Stator 51: Salient pole 52: Yoke 2: Field coil 21: Main coil (Three single poles are in parallel with each other) 22: Subcoil (Three single poles are in series with each other) 6: Armature 7: Drive lever 8: One-way clutch
9: Pinion B: Battery K: Key switch R: Ring gear

Claims (3)

[Claims] A first protruding part which is fitted to a ring gear of an engine;
A pinion that rotationally drives the ring gear, a DC motor that has a stator and an armature and rotationally drives the pinion, a relay that supplementarily energizes the DC motor following a key switch, and protrudes the pinion. A magnet switch that energizes the DC motor when the pinion is fitted to the ring gear, wherein the stator has a series winding in which a plurality of main coils and a plurality of sub-coils are connected in parallel with each other. The sub coil is an auxiliary field coil that is energized through the relay when the key switch is closed, and the main coil is a magnet that closes late after the relay is closed. A main field coil energized through a switch, wherein the relay is a key switch. A starter, wherein the starter is driven to return when opened, and both ends of the sub coil are short-circuited via the armature. 2. The main coil and the sub coil,
The starter according to claim 1, wherein each of the unit poles adjacent to each other is formed. 3. The protruding portion is fitted to a ring gear of an engine,
A pinion that rotationally drives the ring gear, a DC motor that has a stator and an armature and rotationally drives the pinion, and a magnet switch that projects the pinion and energizes the DC motor when the pinion is fitted to the ring gear. And wherein the stator has a series-wound field coil in which a plurality of main coils and a plurality of sub-coils are connected in parallel with each other.