DE102017115094A1 - Camshaft adjuster with a non-return valve plate arranged between a locking cover and a locking plate - Google Patents

Abstract

The invention relates to a camshaft adjuster (1) for use in an internal combustion engine, comprising a stator (2) and a rotor (4) arranged radially inwardly therewith to form a vane cell (3) and with a locking cover offset axially relative to the vane cell (3) (5) to which axially offset to the vane (3) adjacent a locking plate (6) is arranged, through the locking cover (5) and the locking plate (6) through a hydraulic fluid communication between a hydraulic reservoir and the vane is made possible, wherein Axial direction between the locking cover (5) and the locking plate (6) a check valve plate (7) is arranged to control the hydraulic fluid communication.

Description

The invention relates to a camshaft adjuster for use in an internal combustion engine, such as for use in a motor vehicle, with a stator and a radially inside thereof, to form a vane rotor arranged and with an axially offset to the wing cell locking lid, to which axially offset to the Wing cell adjacent a locking plate is arranged. Through the locking lid and the locking plate through a hydraulic fluid communication between a hydraulic reservoir and the vane cell is made possible.

Various camshaft adjusters are known from the prior art, which allow a relative displacement of the stator to the rotor by means of a hydraulic communication in order to realize an adjustment of the camshaft, and thus of the valve opening angle, adapted to the operating state.

In principle, camshaft adjusters engage with a hydraulic fluid / oil pump coupled to the internal combustion engine in order to convey the hydraulic fluid such that a camshaft adjustment is undertaken. That adjustment mechanism is described as oil pressure activated or English as Oil Pressure Activated, OPA.

More recently, so-called smart phasing has been added to those OPA mechanisms. In this case, in addition to the oil pump, the torques present in the camshaft drive are used in order to achieve an improved adjustment behavior / an improved adjustment performance. That adjustment mechanism is described as a cam torque-activated or English as a Cam Torque Activated, CTA, and is approximately in the published patent application DE 10 2012 201 558 A1 disclosed. Here, a necessary for the CTA mechanism oil reservoir is connected via check valves with the at least one vane. These check valves are designed to ensure reliable supply of the vane cells. Once the check valves in the cover / spring cover of the camshaft adjuster are arranged, also the use of a check valve plate is possible, which replaces the individually mounted plug-in check valves.

More cam phasing with a smart phasing technology are in the documents DE 10 2012 201 566 A1 . DE 10 2012 201 570 A1 and DE 10 2012 201 551 A1 disclosed.

From the hydraulic fluid communication / hydraulic adjustment of the camshaft inevitably results in the question of how the stator behaves relative to the rotor when the internal combustion engine / the engine has just been started and the desired hydraulic pressure is not yet applied in the vane. In order to assign a position to the two components stator and rotor in such a state, locking mechanisms are used. These can cause essentially three positions of the stator to the rotor: the early stop, the center lock or the late stop. For reasons such as those in the DE 10 2007 004 196 A1 A center lock provides the most advantages. If a Smart Phaser is equipped with a mid-lock, it is called a Smart Lock technology.

With current smart phasers, the check valve plate rests on the stator on / at the stator. Corresponding flaps / tabs of the non-return valves therefore protrude from the reservoir into the wing cell when the hydraulic fluid supply of the winged cell is present. In order to prevent jamming between the non-return valve plate and the rotor during that protrusion, corresponding pockets are formed in the rotor which point tangentially to the direction of adjustment of the rotor.

These pockets cause the sealing lengths of the wings are reduced or that a lower displacement angle is forced by a circumferentially wider construction of the rotor. Furthermore, the support of the attack of the tabs on the rotor falls away with the appropriate rotor position. For this reason, the tabs in the prior art are to be kept in the range of elastic deflection even at maximum negative pressure, since they would otherwise be leaking in a blocking case. This in turn requires a correspondingly thick check valve plate or a small deflection of the check valve plate, which, however, reduces the flow at a low negative pressure and thus worsens the behavior of the camshaft adjuster overall.

In addition, depending on the material selected, wear of the check valve plate may occur due to a corresponding locking pin, since it runs onto the edge of the sheet, in particular when unlocking.

Against this background, the object of the invention is to eliminate or at least mitigate the disadvantages of the prior art, and in particular to provide such a camshaft adjuster which realizes a smart-lock function with complete sealing of the rotor relative to the stator. Furthermore, the invention aims to provide the check valve plate defined attacks that no relative movement so as to ensure reliable hydraulic fluid communication.

This is inventively achieved in that in the axial direction between the locking cover and the locking plate, a check valve plate is arranged to control the hydraulic fluid communication. Thus, in the area of the vane itself, the check valve plate does not protrude, as a result of which pockets are no longer to be formed in the rotor. This increases a robust functionality of the camshaft adjuster according to the invention.

Advantageous embodiments are the subject of the dependent claims and are explained in more detail below.

Thus, it is advantageous if the locking plate has on its side facing the locking cover at least one indentation / Kuhle / pocket, which is prepared by the check valve plate formed check valve flaps / flaps in a first direction of actuation, namely in the direction of hydraulic fluid of the hydraulic reservoir is conveyed into the wing cell, to ensure a stop. This stop is independent of the position of the rotor to the stator, so that the flap / flap is not exposed to relative rotation, which improves their life due to the decreasing friction.

Preferably, the locking lid has on its side facing the locking plate at least one shoulder, which is prepared to the non-return valve flaps / in another, second actuating direction, namely in the direction in which a hydraulic fluid communication between the hydraulic reservoir and the vane cell is locked to ensure a stop. Also, this stop is independent of the position of the rotor to the stator, so that the flap / flap is not exposed to relative rotation, which improves their life due to the decreasing friction. The shoulder is preferably designed flat in order to ensure a sufficient degree of robustness.

In a further advantageous embodiment, the locking plate is designed as a fully cured component. Since the locking plate is exposed to the relative movement between the stator and the rotor, it is thus able to demonstrate the desired strength and surface quality even under cyclic loading.

In other words, it can be said that the check valve plate / the check valve plate according to the invention is placed between the two components locking cover and locking plate. The check valve plate thus has no contact with the rotor. This allows a simple, slim design of the rotor and also longer sealing lengths. The exemptions / indentations for the stops are introduced exclusively into the locking plate. As a result, a support of the tabs of the check valve plate is always given at maximum negative pressure. The support can also be made flat because of the fixed position to the check valve flap / flap. This allows more freedom in choosing the spring rate of the check valve flap / tab.

The preferably through hardened locking plate also protects the check valve plate from wear. The invention also allows other orientations of the flaps / flaps, if this z. B. space is necessary. For example, a radial alignment of the tabs would also be conceivable.

The two covers are rotated during assembly against each other to adjust the locking clearance, as in the DE 10 2007 004 196 A1 is described. In that construction, the layered lids are also used to accommodate the check valve sheet therebetween. The locking cover acts as a stop in the reverse direction and the locking plate as a stop in the flow direction. The end stop of the locking plate is designed as a ramp to avoid load peaks on the check valve plate. The access points in the locking plate to the vane are preferably semicircular and offset from the valve center points designed to allow a favorable flow and the largest possible flow cross-section. In addition, the exemptions are broadened approximately to compensate for the displacement of the locking cover to the locking plate. The exemptions are about to produce cheap by means of a stamping step. The resulting punctures are preferably subsequently removed by means of a double disc grinding process.

Thus, the invention can be summarized as described, that the check valve plate between the locking cover and the locking plate is placed. The sheet thus has no contact with the rotor. This allows a simple, slim design of the rotor and longer sealing lengths.

• 1 einen perspektivischen Teilschnitt durch einen erfindungsgemäßen Nockenwellenversteller;
• 2 eine Ansicht von oben auf den teilgeschnittenen Nockenwellenversteller; und
• 3 den Bereich III aus 2 vergrößert dargestellt.

The invention will now be explained in more detail with reference to the figures. Show it:

• 1 a perspective partial section through a camshaft adjuster according to the invention;
• 2 a view from above of the partially cut camshaft adjuster; and
• 3 the area III out 2 shown enlarged.

The figures are merely schematic in nature and are for the sole purpose of understanding the invention. The same elements are provided with the same reference numerals.

In 1 is a camshaft adjuster 1 shown for use in an internal combustion engine. A stator 2 , within which a wing cell 3 as well as an in 2 illustrated rotor 4 are arranged, is with a locking lid 5 sealed. Between the locking lid 5 and the wing cell 3 is a locking plate 6 arranged. Through the locking lid 5 and the locking plate 6 Through is a hydraulic fluid communication between a in 1 not shown hydraulic reservoir and the wing cell 3 is possible. To control those hydraulic fluid communication is a check valve plate 7 of needs: this forms non-return valve bags 8th out, the hydraulic fluid openings 9 in the lock plate 6 and hydraulic fluid channels 10 in the locking lid 5 Cover or optionally release.

Is hydraulic fluid from the hydraulic reservoir through the at least one hydraulic fluid channel 10 and the at least one hydraulic fluid port 9 into the wing cell 3 transferred, lies the check valve 8th at a recess 11 on (see also 3 ) coming from the locking plate 6 is trained. If no fluid is transferred, the check valve pocket is 8th closed and lies on a shoulder 12 on, from the latch cover 5 is trained.

In 2 is the camshaft adjuster 1 shown from above. At the wing cell 3 opposite side of the locking lid 5 is a cover bell 13 arranged. The one with III indexed area is in 3 shown in more detail.

3 illustrates the principle of operation of the invention: Between a hydraulic reservoir 14 and the wing cell 3 is the hydraulic fluid along the flow direction, denoted by the reference numeral 15 is provided, between two different pressure levels, the medium Ap are indicated, directed. For this purpose, the first of the locking lid 5 molded hydraulic fluid channel 10 run through. At the hydraulic reservoir 14 opposite side of the locking lid 5 is the check valve plate 6 arranged the check valve 8th formed. When the hydraulic fluid along the flow direction 13 flows, forms the check valve pocket 8th a hub, with the reference numeral 16 is provided. The check valve bag 8th lies here in a recess 11 the locking plate 6 ,

In a state in which no fluid from the hydraulic reservoir 14 into the wing cell 3 is transferred, which is the flow direction 15 opposite reverse direction 17 in front. This will be the check valve 8th against the shoulder 12 pressed and the fluid flow from the hydraulic reservoir 14 into the wing cell 3 prevented.

LIST OF REFERENCE NUMBERS

1

Phaser

2

stator

3

vane

4

rotor

5

locking cover

6

locking plate

7

Check valve plate

8th

Check valve flap

9

Hydraulic center opening

10

Hydraulic fluid channel

11

indentation

12

shoulder

13

Abdeckglocke

14

hydraulic reservoir

15

flow direction

16

stroke

17

reverse direction

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

• DE 102012201558 A1 [0004]
• DE 102012201566 A1 [0005]
• DE 102012201570 A1 [0005]
• DE 102012201551 A1 [0005]
• DE 102007004196 A1 [0006, 0018]

Claims (4)

Camshaft adjuster (1) for use in an internal combustion engine, comprising a stator (2) and a rotor (4) arranged radially inwardly therewith to form a vane cell (3) and with a locking cover (5) offset axially relative to the vane cell (3), a locking plate (6) is arranged adjacent to the winged cell (3), wherein hydraulic communication between a hydraulic reservoir and the winged cell (3) is made possible by the locking cover (5) and the locking plate (6), characterized that in the axial direction between the locking cover (5) and the locking plate (6) a check valve plate (7) is arranged to control the hydraulic fluid communication. Camshaft adjuster (1) to Claim 1 , characterized in that the locking plate (6) has on its side facing the locking cover (5) at least one indentation (11), which is prepared, check valves (8) formed by the check valve plate (7), in an actuating direction to ensure a stop. Camshaft adjuster (1) according to any one of the preceding claims, characterized in that the locking cover (5) on its side facing the locking plate (6) side has at least one shoulder (12) which is prepared, the check valve (8) in a further actuation direction to ensure a stop. Camshaft adjuster (1) according to one of the preceding claims, characterized in that the locking plate (6) is designed as a hardened component.

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