DE102012213402A1 - Camshaft adjusting device, has stator drivable by crankshaft of engine, and securing part extending from tube section towards radial outer windings of spring, and secured in immovable manner in axial direction against tube section - Google Patents

Abstract

The device has a stator (1) drivable by a crankshaft of an internal combustion engine, and a rotor (2) that is rotationally fixed to a camshaft of the internal combustion engine. A torsion spring (5) with helical windings is arranged between the rotor and the stator. A tube section (19) axially protrudes to the associated rotor. A securing part extends from the tube section towards radial outer windings of the torsion spring. The securing part is secured in an immovable manner in an axial direction against the tube section.

Description

The invention relates to a camshaft adjuster with the features of the preamble of claim 1.

A generic camshaft adjuster is for example from the EP 1 979 582 B1 known. The camshaft adjuster has in its basic structure a drivable by a crankshaft stator and a rotatably connected to the camshaft rotor. Between the stator and the rotor, an annular space is provided which is divided by non-rotatably connected to the stator, radially inwardly projecting projections into a plurality of working chambers, which are each divided by a radially projecting from the rotor outwardly wings in two pressure chambers. Depending on the loading of the pressure chambers with a pressure medium of the rotor relative to the stator and thus also the camshaft relative to the crankshaft in the direction of "early" or "late" adjusted. The pressure build-up of the pressure medium also takes place via the crankshaft, with the result that only a small pressure medium flow is provided at low speeds. This low flow of pressure medium has the disadvantage that under unfavorable circumstances, an undesirable adjustment of the camshaft adjuster can occur, which can result in unfavorable consumption of the engine, in particular in the cold start phase, with unfavorable fuel consumption with a troubled run as a result. For this reason, a helical torsion spring is provided between the rotor and the stator in the camshaft adjuster known from EP 1 979 582 B1. The torsion spring is mounted with a radially outer end on a projection associated with the stator with a radially inner end on a pin associated with the rotor. The coil spring is secured by a pressed-in a ring-cylindrical extension of the stator lid to the outside.

The object of the invention is to provide a camshaft adjuster with a helical torsion spring, which is inexpensive to manufacture and easy to assemble.

According to the basic idea of the invention, it is proposed to achieve the object that an axially projecting pipe section assigned to the rotor is provided, and the securing part extends from the pipe section in the direction of the radially outer windings of the torsion spring, and that the securing part bears against the pipe section secured against displacement in the axial direction. The advantage of the proposed solution is to be seen in a simplification of the assembly, which is realized here by a simple sliding of the securing part on the pipe section and a subsequent or simultaneous securing of the securing part relative to the pipe section in the axial direction. Furthermore, the torsion spring is laterally supported much better especially at its radially inner portion.

It is further proposed that the pipe section is part of a tube extending through a central opening of the rotor. The tube can z. B. part of a central screw or part of a central valve, which are provided in the camshaft adjuster, so that the number of parts is not increased by the invention. In addition, the rotor does not have to be structurally changed.

It is also proposed that the securing part extends beyond the second radially outer spring end of the torsion spring and is fixed on its radially outer side on the stator. By the proposed solution, the torsion spring is laterally supported over its entire extent in the radial direction and also the securing part can be additionally stabilized by fixing to the stator. The securing part can thereby also be regarded as a housing for the torsion spring, which on the one hand stabilizes the torsion spring and on the other hand protects against mechanical influences from outside.

It is further proposed that the securing part projects into the pipe section and forms a stop for a guided in the pipe section central valve. The security part can be used in addition to securing the central valve.

This stop can be realized in a particularly simple manner in that the pipe section has at least one slot at the end face, through which the securing part projects with a nose.

According to a further preferred embodiment, it is proposed that the securing part is formed by a securing composite comprising a securing disk and a securing ring securing the securing disk on the pipe portion so as to be non-displaceable. The proposed solution, the locking washer can be secured axially, without having to be simultaneously connected in rotation with the pipe section. The lock washer can thereby z. B. rotatably connected to the stator, so that it rotates with this, while it is fixed axially against displacement of the rotor.

In this case, the nose can be provided to form the stop on the retaining ring, since this is fixed against rotation relative to the pipe section, so that the lock washer can rotate freely relative to the pipe section and at the same time secured against axial displacement.

It is further proposed that the first spring end of the torsion spring is structurally defined particularly simply on the pipe section. This eliminates the provision of separate attachment lugs or pins for the radially inner end of the spring. The end can z. B. be set via a clamp connection or a stop in the circumferential direction.

In particular, the first spring end of the torsion spring can be fixed in a rotationally fixed manner to the pipe section by means of a positive connection, so that the peripheral forces can be transmitted particularly easily.

This can be particularly easily realized by the pipe section is out of round, and the first spring end of the torsion spring is fixed by a shape adapted to the non-circular shape rotationally fixed on the pipe section.

The invention will be described in detail with reference to a preferred embodiment. Show it:

1 a camshaft adjuster with a torsion spring,

2 a camshaft adjuster with a torsion spring and a securing part, and

3 a camshaft adjuster with a torsion spring and a securing part and a central valve.

In the 1 is a camshaft phaser in a sectional view and in view of a torsion spring 5 to recognize. The camshaft adjuster has a stator in its basic construction 1 with an external toothing 3 and a rotor 2 on. The stator 1 is rotatably driven by a crankshaft of an internal combustion engine via a endless traction drive, while the rotor 2 rotatably connected to a camshaft of the internal combustion engine is connectable. Between the stator 1 and the rotor 2 an annular space is present, which is divided by non-rotatably connected to the stator projections in working chambers, which in turn are divided by non-rotatably connected to the rotor blades in opposite pressure chambers. The pressure chambers can be connected to a hydraulic system, via which the pressure chambers for adjusting the rotor 2 and the camshaft relative to the stator 1 and the crankshaft in the direction of "early" or "late" optionally acted upon with pressure medium. The pressure chambers are laterally through sealing cover 4 and 13 locked. The sealing cover 4 and 13 are about pins 15 with the stator 1 or connected to the projections, so that the sealing cover 4 and 13 , the stator 1 and the protrusions can be considered as a more torsionally rigid composite.

In a central opening of the rotor 2 is a pipe 6 arranged with passages for the pressure medium, which with a pipe section 19 over the front of the rotor 2 stands out. Further, a torsion spring 5 provided, which between the rotor 2 and the stator 1 acts. The pipe section 19 is out of round and with a wrench area 9 provided on the first radially inner end of the torsion spring 5 is fixed positively in the circumferential direction. Unless the pipe 6 z. B. part of a central screw for connecting the rotor 2 With the camshaft, the key area can be 9 used simultaneously to tighten the central screw. The torsion spring 5 extends from the first end 7 in a plurality of spiral turns in a plane radially outward to a second end 8th which is attached to one of the pins 15 is mounted.

To secure the torsion spring 5 is one in the 2 to be recognized security part in the form of a security bond from a lock washer 11 and one in a groove on the pipe section 19 engaging circlip 10 intended. The lock washer 11 is with its radial inside between the circlip 10 and on the key area 9 fixed first end 7 the torsion spring 5 arranged so that they slide axially on the pipe section 19 is fixed. Here is the lock washer 11 not firmly clamped, but only so far secured against displacement that they are the torsion spring 5 Secures laterally and at the same time against the pipe section 19 can rotate freely. At the radial outside is the lock washer 11 with an axial collar 20 with single fingers 21 provided over which the lock washer 11 rotatably in corresponding pockets of a collar 22 of the stator 1 intervenes. This is the lock washer 11 rotatably with the stator 1 connected and non-slip on the pipe section 19 secured. Because the lock washer 11 rotatably with the stator 1 connected, the rotor performs 2 with the pipe section 19 of the pipe 6 also the relative rotational movements to the lock washer 11 out. The lock washer 11 is between the circlip 10 and the end 7 the torsion spring 5 arranged with a game, so that the rotation is not hindered.

By the extension of the lock washer 11 from the radial inside of the torsion spring 5 beyond the radial outside of the torsion spring 5 in addition, the torsion spring 5 optimally supported on the side. In addition, the lock washer 11 with a considerably lower press force in the Pockets of the collar 22 of the stator 1 be attached as the lock washer 11 According to the invention in addition to the pipe section 19 is axially secured.

In the 3 is the same camshaft phaser with inserted central valve 12 to recognize. The central valve 12 has a displaceably guided, outwardly projecting piston 18 on, which is moved to drive the camshaft adjuster by an actuator, not shown. The circlip 10 has two opposite noses 17 on, with which the circlip 10 in frontally open grooves 16 of the pipe section 19 is introduced so that the circlip 10 rotatably on the pipe section 19 is fixed. At the same time the circlip engages 10 in a radial groove of the pipe section 19 one, leaving the circlip 10 also axially on the pipe section 19 is secured, and the lock washer 11 secured axially against slipping. This is the torsion spring 5 at its radially inner end of the spring 7 over the lock washer 11 and the circlip 10 axially on the pipe section 19 secured. Unless the lock washer 11 can be widened for mounting in the region of the central opening, the retaining ring 10 also omitted and the lock washer 11 instead also directly for securing in the axial direction in a groove on the pipe section 19 intervention.

Furthermore, the noses protrude 17 so far radially inward that they are the central valve 12 Cover the front side, so that they simultaneously a stop for the central valve 12 form, and the central valve 12 can not slip out.

LIST OF REFERENCE NUMBERS

1

stator

2

rotor

3

external teeth

4

sealing cover

5

torsion spring

6

pipe

7

First spring end

8th

Second spring end

9

key area

10

circlip

11

lock washer

12

central valve

13

sealing cover

14

The End

15

pen

16

groove

17

nose

18

piston

19

pipe section

20

collar

21

finger

22

collar

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 1979582 B1 [0002]

Claims (10)

Camshaft adjuster with - a drivable by a crankshaft of an internal combustion engine stator ( 1 ), and - a rotatably connected to a camshaft of the internal combustion engine rotor ( 2 ), and - one between the rotor ( 2 ) and the stator ( 1 ) acting torsion spring ( 5 ) having helical turns connected to a first radially inner spring end ( 7 ) directly or indirectly with the rotor ( 2 ) and with a second radially outer spring end ( 8th ) directly or indirectly with the stator ( 1 ), and which at an axial end face of the rotor ( 2 ) and the stator ( 1 ) and is secured by a securing part covering the windings laterally to the outside, characterized in that - a rotor ( 2 ), axially projecting pipe section ( 19 ) is provided, and - the securing part starting from the pipe section ( 19 ) in the direction of the radially outer turns of the torsion spring ( 5 ), and that - the securing part with respect to the pipe section ( 19 ) is secured against displacement in the axial direction. Camshaft adjuster according to claim 1, characterized in that - the pipe section ( 19 ) Part of a through a central opening of the rotor ( 2 ) extending pipe ( 6 ). Camshaft adjuster according to one of the preceding claims, characterized in that - the securing part via the second radially outer spring end ( 8th ) of the torsion spring ( 5 ) and at its radially outer side on the stator ( 1 ). Camshaft adjuster according to one of the preceding claims, characterized in that - the securing part in the pipe section ( 19 protrudes and a stop for a in the pipe section ( 19 ) guided central valve ( 12 ). Camshaft adjuster according to claim 4, characterized in that - the pipe section ( 19 ) has at least one slot at the end, through which the securing part with a nose ( 17 ) protrudes. Camshaft adjuster according to one of the preceding claims, characterized in that - the securing part by a securing composite of a lock washer ( 11 ) and a lock washer ( 11 ) on the pipe section ( 19 ) non-slip locking ring ( 10 ) is formed. Camshaft adjuster according to claim 5 and 6, characterized in that - the nose ( 17 ) on the retaining ring ( 10 ) is provided. Camshaft adjuster according to one of the preceding claims, characterized in that - the first spring end ( 7 ) of the torsion spring ( 5 ) on the pipe section ( 19 ). Camshaft adjuster according to claim 8, characterized in that - the first spring end ( 7 ) of the torsion spring ( 5 ) by a form-fit rotation on the pipe section ( 19 ). Camshaft adjuster according to claim 9, characterized in that - the pipe section ( 19 ) is out of round, and - the first spring end ( 7 ) of the torsion spring ( 5 ) by a shape adapted to the non-circular shape rotationally fixed on the pipe section ( 19 ).

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