DE202007012098U1 - starter - Google Patents

Abstract

starter with an electrically operable starter motor (13), wherein the starter motor (13) a stator and a rotor, the stator having a pole housing (28) has, which is suitable for conducting magnetic flux and wherein the for the magnetic flux conductive Area of the pole housing (28) an outer diameter (D) and the stator is energized by permanent magnets (31) a radial height (h), wherein a ratio (k) a quotient of the outer diameter (D) and the height (h) is where the ratio (k) is less than ten.

Description

State of the art

To the Starting internal combustion engines are mainly mechanically commutated DC motors for use. These DC motors are usually with one Planetary gear equipped with the required torque to be able to form a small electric motor. For starters for cars or Starters for small commercial vehicles (internal combustion engines with petrol or diesel combustion process up to approx. 3 liters displacement) have permanent magnetically excited starter motors enforced. They are magnets in a magnetically conductive pole tube installed, which generate the field required for moment forming. The design of the starter is conventionally typically for the short term Operation and according to the normal requirements for 30 000 Up to 60,000 switching cycles, that is to say start-ups, are suitable. These normal requirements are a few starts per trip. First and foremost, these interpretations are required to the appropriate Number of switching cycles aligned, costs play the market role.

used such normal starters in so-called start-stop applications, so, as we have noted, this results in usage from next larger normal Starters (related to a specific engine displacement) problems. A increased acceleration capability at moderate current consumption using a starter of next larger series goes for start-stop applications with a higher one Power consumption accompanied, which is undesirable is. A vehicle with a start-stop mode usually starts up to 10 times more than a normal vehicle its internal combustion engine. this leads to in that the current consumption of the starting device takes place more frequently and is therefore charged too frequently with the same starter battery. It exists the danger that the battery is ultimately too weak to consistently carry out the start-stop procedure.

The Use of a starter of the next larger series has the disadvantage that the rotor of the starter motor then also a higher moment of inertia has, since this builds larger in diameter. This is insofar disadvantageous in that the acceleration capability of the rotor is reduced and thus use in a start-stop system tends to be dissatisfaction because the internal combustion engine stops at a stop phase, For example, at a traffic light, only unsatisfactorily fast again can be started. This starter is therefore too slow.

Disclosure of the invention

It it was found that the described functional requirements in terms of accelerability, low power consumption and also additional torque boost then Fulfills can be if the starting device is in for the magnetic flux conductive Area of the pole housing an outer diameter D has, the stator is excited by permanent magnets, which has a radial height of h and a ratio k <ten. k is a quotient from the outer diameter D and the height H. Parallel to this is when using the starting device on a larger starter battery (higher Capacity) the Demagnetisierfestigkeit sufficiently large.

Based on an electrical part of the same remained the same diameter Rotor (outer diameter Disc pack) this means that the outer diameter of the starter motor enlarged and characterized in Polrohr a corresponding to the larger thickness of the permanent magnets a bigger river is provided without using a more expensive magnetic material must become. This river increase reduces the current consumption of the rotor to a certain torque provide. At the same time, the armature moment of inertia remains similarly low, as it would be with a certain normal application. The result is the ability to accelerate elevated. As already mentioned, have the "thick" magnets also one increased Demagnetization on, allowing the starter for operation on larger batteries can be allowed, what for the start-stop application is preferred.

One positive effect regarding the manufacturing cost is that with skillful choice of the new outer diameter, the pole tube of the next can be used in the product program existing size. Consequently are e.g. operated with a rotor several torque classes, the is called, a rotor fits in different pole tubes with different ones Permanent magnets, so that these pairings of the rotor with different Pole tubes and permanent magnets at different torques to lead.

Of Another is the use of a larger pole tube for applications with higher load cycles an enlarged space for the design wear parts, such as. the carbon brushes or the planetary gear, available.

It it is envisaged that the permanent magnets are ferrite magnets.

Short description of the drawing

The invention will be exemplified below explained in more detail with reference to the figure. This figure shows a starting device in a longitudinal section.

1 shows a starting device in a longitudinal section. In the 1 is a starting device 10 shown. This starting device 10 For example, has a starter motor 13 and an engagement relay 16 on. The starter motor 13 and the engagement relay 16 are on a common drive end shield 19 attached. The starter motor 13 Functionally, it serves as a starter pin 22 drive it when in the sprocket 25 the internal combustion engine, not shown here is eingespurt.

The starter motor 13 has a pole tube as a housing 28 on, on its inner circumference permanent magnets 31 wearing. The stator is out of the pole tube 28 and in the pole tube 28 attached permanent magnets 31 educated. The pole housing or pole tube 28 has a diameter D. The permanent magnets 31 have a height h, which is directed in the radial direction to the axis of rotation of the drive shaft. The permanent magnets 31 in turn surround an anchor 37 that made a slats 40 built anchor package 43 and one in grooves 46 arranged armature winding 49 having. The anchor package 43 is on a drive shaft 44 pressed. At the starter pin 22 opposite end of the drive shaft 44 is also a commutator 52 attached, among other things from individual Kommutatorlamellen 55 is constructed. The commutator bars 55 are in known manner with the armature winding 49 electrically connected in such a way that when the commutator bars are energized 55 through carbon brushes 58 a rotary motion of the anchor 37 in the pole tube 28 results. One between the Einspurrelais 16 and the starter motor 13 arranged power supply 61 supplies both the carbon brushes when switched on 58 as well as the excitation winding 34 with electricity. The drive shaft 44 is commutator side with a shaft journal 64 in a plain bearing 67 supported, which in turn in a Kommutatorlagerdeckel 70 is held stationary. The commutator cover 70 turn is by means of tie rods 73 that go beyond the circumference of the pole tube 28 are distributed (screws, for example, 2, 3 or 4 pieces) in the drive end shield 19 attached. It supports the pole tube 28 at the drive end plate 19 off, and the commutator bearing cap 70 at the pole tube 28 ,

In drive direction closes to the anchor 37 a so-called sun wheel 80 on, the part of a planetary gearbox 83 has. The sun wheel 80 is from several planet wheels 86 surrounded, usually three planet wheels 86 by means of roller bearings 89 on axle journal 92 are supported. The planet wheels 86 roll in a ring gear 95 off, in the pole tube 28 is stored outside. Towards the output side closes to the planetary gears 86 a planet carrier 98 in which the axle journals 92 are included. The planet carrier 98 will turn into an interim storage 101 and a slide bearing arranged therein 104 stored. The interim storage 101 is designed pot-shaped, that in this both the planet carrier 98 , as well as the planet wheels 86 are included. Furthermore, in the cup-shaped intermediate storage 101 the ring gear 95 arranged, which ultimately by a cover 107 opposite the anchor 37 closed is. Also the interim storage 101 supports with its outer circumference on the inside of the pole tube 28 from. The anchor 37 indicates that of the commutator 52 opposite end of the drive shaft 44 another shaft journal 110 on, who also in a plain bearing 113 is absorbed, from. The plain bearing 113 in turn is in a central hole of the planet carrier 98 added. The planet carrier 98 is integral with the output shaft 116 connected. This output shaft 116 is with her from the interim storage 101 opposite end 119 in another camp 122 , which in the drive end shield 19 is fixed, supported. The output shaft 116 is divided into different sections: So follows the section that is in the plain bearing 104 of the interim storage 101 is arranged, a section with a so-called spur toothing 125 (Internal toothing), which is part of a so-called shaft-hub connection. This shaft-hub connection 128 allows in this case the axially rectilinear sliding of a driver 131 , This driver 131 is a sleeve-like extension, which is integral with a cup-shaped outer ring 132 of the freewheel 137 has. This freewheel 137 (Richtgesperre) consists further of the inner ring 140 that is radially inward of the outer ring 132 is arranged. Between the inner ring 140 and the outer ring 132 are clamp bodies 138 arranged. These clamp bodies 138 prevent, in cooperation with the inner and outer ring relative rotation between the outer ring and the inner ring in a second direction. In other words: the freewheel 137 allows a relative movement between the inner ring 140 and outer ring 132 only in one direction. In this embodiment, the inner ring 140 integral with the starter pinion 22 and its helical toothing 143 (External helical teeth) executed.

For the sake of completeness, the single-track mechanism should be considered here. The push-in relay 16 has a bolt 150 on, which is an electrical contact and which is connected to the positive terminal of an electric starter battery, which is not shown here. This bolt 150 is through a relay cover 153 passed. This relay cover 153 closes a relay housing 156 from, by means of several fasteners 159 (Screws) on the drive end plate 19 is attached. In the engagement relay 16 is still a pull-in winding 162 and a so-called holding winding 165 arranged. The intake winding 162 and the stops development 165 both cause each in the on state an electromagnetic field, which both the relay housing 156 (made of electromagnetically conductive material), a linearly movable armature 168 and an armature conclusion 171 flows through. The anchor 168 carries a push rod 174 , when linear insertion of the anchor 168 towards a shift pin 177 is moved. With this movement of the push rod 174 to the shift pin 177 This is from its rest position towards two contacts 180 and 181 moved, leaving a on to the contacts 180 and 181 End of the shift pin 177 attached contact bridge 184 both contacts 180 and 181 connects electrically with each other. This is done by the bolt 150 electrical power via the contact bridge 184 away to the power supply 61 and thus to the carbon brushes 58 guided. The starter motor 13 is energized.

The engagement relay 16 or the anchor 168 but also has the task, with a tension element 187 one the drive end shield 19 to move rotatably arranged lever. This lever 190 , usually designed as a fork lever, engages with two "tines" not shown here on its outer circumference two discs 193 and 194 to a between this clamped driving ring 197 to the freewheel 137 towards the resistance of the spring 200 to move and thereby the starter pinion 22 in the sprocket 25 einzuspuren.

It thus becomes a starting device with an electrically operable starter motor 13 suggested, the starter motor 13 a stator and a rotor (armature 37 ), wherein the stator has a pole housing in the form of a pole tube 28 has, which is suitable for conducting magnetic flux. The magnetic flux conducting region of the pole housing or pole tube 28 has an outside diameter D. The stator is made by permanent magnets 31 excited, which have a radial height h. It is provided that a ratio k is a quotient of the outer diameter D of the pole tube 28 and the height h of the permanent magnets 31 where k <ten.

The permanent magnets 31 should be ferrite magnets.

The permanent magnets 31 are each by holding springs 32 secured in the pole tube.

Claims (2)

Starting device with an electrically operable starter motor ( 13 ), wherein the starter motor ( 13 ) has a stator and a rotor, wherein the stator is a pole housing ( 28 ), which is suitable for conducting magnetic flux and wherein the magnetic flux conductive region of the pole housing ( 28 ) has an outer diameter (D) and the stator by permanent magnets ( 31 ), which has a radial height (h), wherein a ratio (k) is a quotient of the outer diameter (D) and the height (h), wherein the ratio (k) is less than ten. Starting device according to claim 1, characterized in that the permanent magnets ( 31 ) Are ferrite magnet.