DE102008040106A1 - Starter for an internal combustion engine - Google Patents

Abstract

The invention relates to a starter (1) for an internal combustion engine, with a pinion (2) pushed onto a shaft (3) and with an axial securing device (6) securing the pinion (2) on the shaft (3). It is envisaged that the axial securing device (6) is a ring element (7) which is pushed onto the shaft (3) and held in frictional engagement.

Description

The Invention relates to a starter for an internal combustion engine, with a pushed on a shaft pinion and with a Pinion on the shaft securing axial lock.

Beach of technology

starter are known in the art for starting internal combustion engines. A pinion spurts in a rotationally fixed with the crankshaft of the internal combustion engine connected gear and drives the crankshaft in this way on until the internal combustion engine ignites and runs on its own. For free ejecting Starters the starter pinion is stored in a drive bearing with needle sleeve starters. At the starter assembly, the freewheel with the starter pinion is through the needle sleeve together. The maximum head circles and numbers of teeth the starter variants are therefore limited. The muted or Spring-loaded application of the starter pinion to the ring gear is included Tooth-to-tooth contact is not guaranteed. By increase of required starting speeds, run-up assistance for the internal combustion engine and required life in start-stop operation, it is necessary to Number of teeth and thus also to increase the tip circle diameter at the starter pinion. With the solutions known from the prior art, in particular in embodiments with the described needle sleeves, this is not montage technical or only with considerable change the assembly lines possible. Needle sleeves with larger inner ring and mutual sealing divorced for cost reasons and from the point of view of mountability. Next would have the shaft diameter of the starter pinion in extrusion execution to the diameter the larger head circle be adapted, which in turn due to the larger mass of the component the Dynamics of the starter and the weight of the complete product negatively influenced. It is known so far, the pinion as Steckritzel perform, mounted at the end of the starter assembly and then axially is secured. As axial securing is an axial in the prior art Fixation by means of snap ring and / or stop ring in the manner of a Seeger rings known. The disadvantage of this is an increased installation costs as well an elevated one Space requirements and in the embodiment the as free ejecting Starter an additional Capsule for closing of the starter pinion.

task the invention is to provide a starter for an internal combustion engine, which provides a corresponding pinion and thereby a simple, inexpensive Assembly guaranteed as Steckritzel without the disadvantages described above accepted Need to become.

Disclosure of the invention

For this becomes a starter for proposed an internal combustion engine, with a deferred on a shaft Pinion and with a pinion on the shaft securing axial. It is envisaged that the axial securing a pushed onto the shaft, is frictionally held ring element. The axial securing is As a result, causes the ring member pushed onto the shaft and held there in frictional engagement. The ring element has this an inner diameter that matches the outer diameter of the shaft exactly corresponds that in the deferred state on the material-related frictional forces is held in place. For the purpose of assembly, this will Ring element pushed onto the shaft and fixes the pinion thereby.

Prefers the ring element is pushed onto the shaft under the action of ultrasound. Due to the ultrasound effect during pushing is reduces the sliding friction between the shaft and the ring element, so pushing the pinion onto the shaft without too much effort possible is. At the same time it is avoided that the ring element for the purpose of postponement, for example, must be heated to thermal Expansion of the ring element about a diameter extension of the To effect ring element, as for example when bursting he follows. A Ultraschallleitwirkung can be much easier and especially with considerable time savings.

In a preferred embodiment the ring element is a pot element. It therefore encompasses the Wave not only outside circumference, but also on the front side with its bottom of the pot. This will be also sealing functions or closure functions provided.

In an embodiment the shaft is a hollow shaft.

Prefers the hollow shaft is axially displaceable on a drive shaft of the Starters stored. The hollow shaft serves here by their Axialverschieblichkeit the disengagement of the pinion and meshing to start in the corresponding gear the crankshaft or crankshaft pulley, wherein a corresponding mimic provided in cooperation with the drive shaft is.

In a further embodiment, the pot element with its bottom of the pot closes the hollow shaft at the end. As a result, a closure of the hollow shaft is effected, which prevents the penetration of dirt and foreign bodies into the hollow shaft very advantageous and reliable, whereby a Stö tion of a displacement mechanism therein, in particular the drive shaft is avoided in a simple and advantageous manner. Furthermore, the undesirable discharge of, for example, lubricant, such as grease, from the hollow shaft is avoided. In particular, it is further avoided that an additional element must be used to close the hollow shaft.

Further is provided in a preferred embodiment, that the pinion rotatably and axially displaceable on the hollow shaft is arranged. The hollow shaft thus rotates the pinion, wherein it is axially displaceable on the hollow shaft to a certain extent outsourced. The moment transmission takes place here by the non-rotatable arrangement, for example via a Rotational drive, which allows a certain Axialverschieblichkeit. hereby is achieved that the pinion when meshing with a tooth-on-tooth contact give way on the hollow shaft in the way of its Axialverschieblichkeit can and so damage the sprocket and / or sprocket into which the pinion meshes, is avoided.

Especially It is preferably provided that the pinion by means of a spring, in particular Belleville spring, is biased axially in the direction of the ring member. The Axialverschieblichkeit the pinion on the hollow shaft is hereby limited by the spring and its bias, which it exerts on the pinion, respectively steamed. Especially with tooth-on-tooth contact of the pinion with the sprocket into which the pinion meshes becomes a short, cushioned yielding of the pinion by this steamed Axialverschieblichkeit guaranteed, where the pinion back into its intended starting position just because the bias returns, once the tooth-on-tooth contact is lifted and the pinion with the sprocket combs.

Further a method is proposed for securing a pinion of a Starters, in particular as described above, on a shaft, wherein a ring member for forming the axial securing to the shaft deferred and thereby held in frictional engagement. The ring element holds accordingly by friction after sliding. Another fixation, in particular a welding, pinning, Solder or similar not necessary.

In further training is postponed under Ultrasound. The ultrasonic effect increases the sliding friction while of postponing to a great extent or at least reduce it to such an extent that the Sliding the ring element on the shaft without too much effort possible is. In particular, this is a relatively quick and inexpensive installation of the ring element allows axial locking, as a thermal Treatment of the ring element for diameter extension as in Blasting or an additional welding, Screwing, pinning or the like eliminated.

Further advantageous embodiments emerge from the dependent claims and combinations thereof.

Brief description of the drawings

The Invention will be explained in more detail with reference to an embodiment without but limited to this to be.

It shows

the Figure a pinion of a starter for an internal combustion engine with Axial locking.

Embodiment (s) the invention

The figure shows sections of a starter 1 for an internal combustion engine, not shown, with a pinion 2 that on a wave 3 as a hollow shaft 4 is formed, is deferred. The pinion 2 stored on the hollow shaft 4 rotationally fixed about a rotational drive, not shown, but to a small extent, namely the width of a gap 5 , axially displaceable. The wave 3 is end to the axial securing of the pinion 2 on the wave 3 with an axial lock 6 provided in the form of a ring element 7 in a special embodiment as a pot element 8th is trained. The hollow shaft 4 is axially displaceable on a drive shaft 9 the starter 1 stored, wherein the hollow shaft 4 to effect disengagement for meshing the pinion 2 in a ring gear, not shown, axially displaceable up to a bearing stop 10 is stored. When meshing, the pinion can 2 by its own Axialverschieblichkeit on the hollow shaft 4 in the circumference of the gap 5 give in to be able to catch a tooth-on-tooth contact and damage the pinion 2 and to avoid the ring gear, not shown. The pinion 2 is in the direction of the axial securing 6 over a spring 11 namely a diaphragm spring 12 , pretensioned. The feather 11 rests on the pinion 2 on the one hand and on a hollow shaft stage 13 on the other hand. The pot element 8th covers a cavity 14 inside the hollow shaft 4 , which is open at the end and with removed pot element 8th Access to the storage stop 10 and to the drive shaft 9 granted. For applying the ring element 7 on the hollow shaft 4 will be at least the ring element 7 with ultrasound 15 applied to the sliding friction during the sliding between ring element inner surface 16 and hollow shaft outer shell 17 reduce so far that without applying too much pressing force the ring element 7 on the hollow shaft 4 slides open. After the end of exposure to ultrasound 15 becomes the ring element 7 on the hollow shaft 4 held by friction. In this way, a further component, for example a snap ring, is very advantageously saved. Furthermore, as in the prior art when using snap rings usual hollow shaft cover is saved. An additional fixation of the ring element 7 on the wave 3 not necessary.

Claims (10)

Starter for an internal combustion engine, with a pushed onto a shaft pinion and with a pinion on the shaft securing axial, characterized in that the axial ( 6 ) on the shaft ( 3 ) pushed, frictionally held ring element ( 7 ). Starter according to claim 1, characterized in that the ring element ( 7 ) under the action of ultrasound on the shaft ( 3 ) is postponed. Starter according to one of the preceding claims, characterized in that the ring element ( 7 ) a pot element ( 8th ). Starter according to one of the preceding claims, characterized in that the shaft ( 3 ) a hollow shaft ( 4 ). Starter according to one of the preceding claims, characterized in that the hollow shaft ( 4 ) axially displaceable on a drive shaft ( 9 ) of the starter ( 1 ) is stored. Starter according to one of the preceding claims, characterized in that the pot element ( 8th ) with its bottom of the pot hollow shaft ( 4 ) closes at the end. Starter according to one of the preceding claims, characterized in that the pinion ( 2 ) rotatably and axially displaceable on the hollow shaft ( 4 ) is arranged. Starter according to one of the preceding claims, characterized in that the pinion ( 2 ) by means of a spring ( 11 ), in particular disc spring ( 12 ), axially in the direction of the ring element ( 7 ) is biased. Method for securing a pinion of a starter, in particular according to one of the preceding claims, on a shaft, wherein a ring member pushed to form the axial securing to the shaft and thereby held in frictional engagement. Method according to claim 9, characterized in that that the postponement takes place under the action of ultrasound.