DE102014223503A1 - Fast-switching hydraulic camshaft adjuster with two check valves in the same direction - Google Patents

Abstract

The invention relates to a hydraulic camshaft adjuster (1) having a drive component (2), such as a sprocket, a toothed wheel or a belt pulley, with an output component (3), such as a camshaft (7) or an intermediate component rotatably connected to the camshaft (7) , with a working space (10) which a piston (11) subdivides into two pressure chambers (14) such that a relative movement between the drive component (2) and the output component (10) is achieved by a relative movement of the piston (11) in the working space (10). 3), and with a main valve (4), the main valve (4) having a feed port (P) for fluidly connecting to a pressure source such as a pump (20), a drain port (T) for fluidly communicating with a pressure sink, as a tank (22), and two working ports (A, B), one of which in each case one of the two pressure chamber (14) is connected, wherein the main valve (4) for selectively fluid Verbi Nden of the inlet port (P) with one of the two working ports (A, B) and the drain port (T) with the other of the two working ports (B, A) or for fluidic locking of both working ports (A, B) is set, further both pressure chambers (14) are each fluidically connected to the inlet port (P) via a non-return valve (25) designed and arranged in such a way that each permits a fluid passage to the inlet port (P) at an overpressure in the respective pressure chamber (14)

Description

The invention relates to a hydraulic camshaft adjuster with a drive component, such as a sprocket, a toothed wheel or a belt pulley, with an output component, such as a camshaft or an intermediate component which can be connected non-rotatably to the camshaft, with a working space which a piston is divided into two pressure chambers, a relative movement or a relative displacement or a phase shift between the drive component and the output component can be effected or forced by a movement of the piston in the working space, and with a main valve, the main valve having an inlet connection for fluidically connecting to a pressure source, such as a pump, a drain port for fluidly communicating with a pressure sink, such as a tank, and two working ports, one of which is connected to each one of the two pressure chambers, wherein the main valve for selectively fluidically connecting the Inlet connection with one of the two working ports and the drain port is set up with the other of the two working ports or for fluidic locking of both working ports.

Gas exchange valves of internal combustion engines can be actuated by cams of a camshaft. About the arrangement and shape of the cam, the opening and closing times of the gas exchange valves are specifically defined. The camshaft is usually actuated, driven and / or driven by a crankshaft of the internal combustion engine. The opening and closing times of the gas exchange valves of the internal combustion engine are usually specified by a relative rotational position or phase position or angular position between the cams and the crankshaft. By changing this relative rotational position between the camshaft and the crankshaft, a variable adjustment of the opening and closing times of the gas exchange valves can be achieved. Due to the variable adjustment of the opening and closing times of the gas exchange valves, for example, the exhaust behavior can be positively influenced depending on the current operating state of the internal combustion engine, the fuel consumption can be reduced, the efficiency can be increased, and / or can the maximum torque and / or maximum power the internal combustion engine can be increased.

This variable adjustment of the opening and closing times of the gas exchange valves can be made or made possible by a provided between the crankshaft and the camshaft camshaft adjusting device or device or such a camshaft adjuster.

There are several principles for driving the adjustment known. One of these drives is the torsion-assisted drive, TA drive ("torque assist"). In the TA drive, the variable displacement is achieved by conveying a hydraulic fluid through a pressure source, such as a pump, into a pressure chamber, while from the other pressure chamber the hydraulic fluid is delivered to a pressure sink, such as a tank. Thus, the TA drive the camshaft adjuster is driven by the energy of a pressure source.

Another of these drives is the cam torque actuated drive, or "cam torque actuated" (CTA). In the CTA drive, the variable displacement is achieved by a force acting from the camshaft to the pressure chambers torque or such a force promotes the hydraulic fluid from one pressure chamber into the other pressure chamber. This torque is thus generated during the cam overruns during operation, and is also referred to as an alternating torque, an alternating torque, a reaction torque or a reaction torque.

The principles of a TA drive and a CTA drive are discussed below.

However, it should be noted at this point that refer to the terms camshaft adjuster drive, camshaft drive, drive member and output member to a transfer of power between the crankshaft and the camshaft. In contrast, the terms adjuster drive, CTA drive, TA drive, operating mode and drive mode relate to a variable adjustment, and thus to a change in the phase angle between the crankshaft and the camshaft.

The TA drive has the advantage that it can be actuated independently of the operating state of the internal combustion engine, that is to say with a rotating camshaft and with a non-rotating camshaft. However, the TA drive has the disadvantage that the adjustment speed is directly dependent on the delivery rate / delivery rate of the pressure source connected to the admission port. This is also referred to as a fluid quantity-limited adjustment readiness.

The CTA drive has the advantage that due to the relatively short delivery paths from one of the pressure chambers into the other pressure chamber and / or due to the relatively high forces or torques within the camshaft adjuster, the adjustment speed is relatively high; that is, the adjustment speed is in the CTA drive in the Usually higher than the TA drive. However, the CTA drive has the disadvantage that for adjusting a rotating camshaft or, in other words, an actuating force between a cam and a plunger or the like must be present. Therefore, the CTA drive, for example, only limited use in internal combustion engines with cylinder deactivation.

A camshaft adjuster of the aforementioned type is for example in the DE 10 2005 052 481 A1 described. This relates to a control valve for a device for the variable adjustment of the timing of gas exchange valves of an internal combustion engine with a hollow valve housing having at least one inlet port (P), at least one drain port (T) and at least two working ports (A, B), and with a Control piston, wherein disposed within the valve housing, a hollow executed Druckmitmitelleiteinsatz and at least one, substantially in the axial direction extending pressure medium channel is formed, wherein the pressure medium passage of the Druckmittelleiteinsatz is at least partially encompassed, wherein the pressure medium channel with at least one of the terminals (A, B, P , T) and communicates via a radial opening with the interior of the Druckmittelleiteinsatzes and wherein the control piston is disposed within the Druckmittelleiteinsatzes. The DE 10 2005 052 481 A1 So describes a control valve of a camshaft adjuster with TA drive.

A camshaft phaser is desired that combines both the fast CTA-type adjustment times and the TA-type adjustment function availability.

Another camshaft adjuster of the type mentioned is, for example, in DE 11 2011 103 133 T5 described. This relates to a phaser having a housing and a rotor arranged for rotation with respect to each other, the housing and the rotor defining at least one cavity interposed therebetween, divided by a vane into a first chamber and a second chamber wherein the phaser further includes channels connecting the first chamber and the second chamber to facilitate swinging of the vane in the cavity, the phaser comprising: a check valve; and a control valve having a spring loaded longitudinally reciprocable spool operable between at least one cam torque actuated (CTA) mode of operation, at least one torsional assisted (TA) mode of operation, and at least one null position, the spool in various longitudinal positions the first chamber, the second chamber, the check valve and an actuating fluid supply source interconnects.

The DE 11 2011 103 133 T5 So, in short, describes a camshaft adjuster with CTA drive. However, this only works in one of two adjustment directions as a TA drive. Furthermore, the sees DE 11 2011 103 133 T5 a check valve axially centrally in the central valve before, which firstly this design is relatively complex, multi-part and complex, making this design secondly requires a relatively large amount of axial space in internal combustion engine longitudinal direction, and thus this design thirdly not with simple means to a TA drive in the other Adjustment can be extended.

The present invention has the object to improve the known camshaft adjuster. In particular, a camshaft adjuster is to be provided, which provides both the CTA function and the TA function in both adjustment directions. The camshaft adjuster should be simple and inexpensive. The camshaft adjuster should, in other words, allow rapid adjustment.

This object is achieved according to the invention in a generic camshaft adjuster in that both pressure chambers are fluidically connected to the inlet connection via a non-return valve configured and arranged in such a way that each permits a fluid passage to the inlet connection at an overpressure in the respective pressure chamber. This has the consequence that the camshaft adjuster is driven by the main valve in a TA mode, with any occurring alternating moments are used in the adjustment, to achieve the desired phase position quickly or faster than a TA alone drive.

It should be noted at this point that in addition to "allow a fluid passage" and the term "let through" is used, the term "let through" defines the forward direction and, in reverse, the reverse direction of a check valve.

By "connect fluidly" is meant a dense connection through which a fluid can flow, which does not necessarily have to be designed as a conduit, but also as a volume, as a connection, as a cross section, as an integration of two components into one another or the like can.

Advantageous developments of the invention are claimed in the subclaims and are explained below.

It can be provided with a plurality of working spaces a camshaft adjuster. Thus, for example, a parallel connection of the work spaces can be provided in order to achieve, for example, high adjustment forces at low pressures, so that, for example, all components can only be designed for these low pressures. It can also be provided a series connection of the working spaces, for example, to allow a high speed of movement of the piston when driven by a plurality of pumps.

Further, it can be provided that all or only a plurality of equally effective pressure chambers share a common non-return valve in order to save costs, for example, by reducing the number of parts. Developing can also be provided that all or only individual pressure chambers each have a separate check valve is assigned to achieve, for example, at relatively small flow rates small check valves in a small space and / or small weight.

The camshaft adjuster according to the invention can be configured in the manner of an axial piston or can be of the axial piston type. An axial piston-type camshaft adjuster, for example, has a single working space with a single piston, so that only relatively little effort is required to produce the fluidic connections. In this case, the drive component and the output component are preferably connected to the piston for effecting the relative movement in each case via a helical toothing, wherein the piston is axially movable. Thus, a coupling of piston movement and phase position change between the drive part and the output part is achieved in a simple mechanical manner.

The camshaft adjuster according to the invention can also be designed in the manner of a rotary piston or can also be of the rotary piston type. A rotary piston-type camshaft adjuster, for example, has a direct coupling of the rotary piston and the phase position change, so that a rotary piston-type camshaft adjuster can be mechanically constructed in a relatively simple and cost-effective manner. It is preferable if the drive member is a stator when the output member is a rotor, and when the piston is rotatable to effect relative movement about a common axis of the input member and the output member. It is particularly preferred if the working space is defined by an inner contour of the stator and an outer contour of the rotor, because this can save additional parts.

It is also particularly preferred in a rotary piston-type camshaft adjuster, when the piston is designed as a rotor-fixed wing, because this simplifies assembly due to reduced number of parts and because this allows direct coupling of the rotor with the adjustment of the camshaft adjuster.

If at least one check valve is arranged and / or integrated in the wing, then the check valve is directly adjacent to the respective pressure chamber, so that short paths of the respective fluidic connection are made possible. This allows a particularly fast or rapid adjusting movement. It may therefore be provided, for example, that a check valve or both check valves are arranged and / or integrated in the wing.

If a valve supply line is formed in the wing, which fluidly connects one of the pressure chambers with the respective check valve, this also allows short paths of the respective fluidic connection and thus a particularly fast or rapid adjusting movement. The valve inlet may be formed, for example, as a hole in the wing, so that the valve inlet is very inexpensive to produce.

There may be provided a valve connection line which fluidly connects the respective check valve or the check valves to the inlet port of the main valve. By means of the valve connection line, a fluid which has been passed to the inlet connection at an overpressure in the respective pressure chamber can be slid to the inlet connection. The valve connection line thus allows short distances of the respective fluidic connection, and thus allows a particularly rapid adjusting movement.

According to an independently claimable aspect of the invention, a main valve for a camshaft adjuster with two cooperating pressure chambers is proposed, which has a feed port for fluidly connecting to a pressure source such as a pump, a drain port for fluidly connecting to a pressure sink such as a tank or a suction port Pump, and two working ports for fluidly connected to each having one of the two pressure chamber of the camshaft adjuster, wherein the main valve for selectively fluidic connection of the inlet port with one of the two working ports and the drain port with the other of the two working ports or for fluidic locking of both working ports is controllable wherein the main valve has a return connection fluidically connected to the inlet connection, by means of which a positive pressure in one of the pressure chambers to the inlet connection is passable. this has Also, as a result, that the camshaft adjuster is driven by the main valve in a TA mode, with any occurring alternating moments are used in the adjustment, to achieve the desired phase position quickly or faster than a TA alone drive.

There may be provided a central check valve which fluidly connects the inlet port to the pressure source, the central check valve being arranged to pass from the pressure source to the inlet port, and wherein the check valves open downstream of the central check valve to the inlet port. By providing this central check valve can be particularly reliably prevented that a fluid is introduced into a supply line between the pressure source and the inlet port by the occurrence of an alternating torque. This has the advantage that the supply line has to be designed only for the maximum pressure of the pressure source and not for the maximum pressure caused by an alternating torque, and secondly has the advantage that the fluid moved by an alternating torque reliably flows into the intended pressure chamber. The central check valve thus causes an increased reliability of the system and causes a faster adjustment of the camshaft adjuster. The central check valve may also be provided integrated in the main valve or central valve.

Optionally, a resiliently preloaded check valve may be provided so that it allows a fluid passage only from a predetermined pressure difference or opens in the forward direction only from a predetermined pressure difference. This can be used as a backup function to prevent a permanently open position of the respective check valve. This may also be used as a control function so as not to allow passage of small pressure differences, pressure surges or pressure oscillations in the passage direction, whereas in terms of magnitude large pressure differences, pressure surges or pressure oscillations in the passage direction are to be transmitted. It can be provided further education that all check valves have the same threshold pressure difference, for example, to keep for cost reasons only one type of check valve in stock. It may also be provided that the check valves have different threshold values, for example in order to compensate for their different throttle action values or flow resistance coefficients in the case of different lines, and / or for the different adjustment directions (post-early adjustment, post-late adjustment). set different thresholds.

In order to be able to use the CTA mode more effectively, it is possible to force the hydraulic fluid to remain in the camshaft adjuster, for example by providing the fluidic connection of the pressure chamber (s) to the discharge port and / or to the pressure sink with a separate throttle. Instead of a separate throttle can make the effective diameter of the fluidic connection of the pressure chamber / -n with or to the drain port and / or to the pressure sink smaller than the effective diameter of the fluidic connection of the pressure chambers via the respective check valve.

According to a further, independently claimable aspect of the invention, the check valve may be a sheet metal part or designed as a sheet metal part. Sheet metal is a cost-effective semi-finished product and sheet metal processing is inexpensive and easy. The term "sheet" is hereby illustrative and although a steel sheet is preferred, other metallic materials, such as copper, aluminum, titanium or the like, and non-metallic materials, such as plastics or fiber-reinforced plastics should be considered. The term "sheet metal" is intended to refer to the result such that, for example, a steel sheet is formed into the check valve by punching, cutting, pressing, embossing, bending, or the like, or such that, for example, a plastic part flat in the end is formed into a urine, or so for example in the end, flat part is milled / turned from the solid.

There may be summarized two such check valves to a check double valve. As a result, a number of parts can be reduced, so that the costs are reduced. The same of course also applies in the event that at least two such check valves are combined to form a check multiple valve. Such a check double valve should also be independently claimable.

A check valve and / or a check double valve may be integrally formed to reduce the number of parts and thus the cost.

The check valve may have, for example, a main body portion or main portion and at least one locking portion. At this time, the main body portion supports the lock portion, and the main body portion is prepared to be supported in / on the camshaft adjuster. This ensures that the locking portion is storable on the camshaft adjuster.

The lock section can, further education, be designed spoon-shaped. Preferably, the locking portion has a main block portion and a Connecting portion. Here, the round in a plan view part of the spoon corresponds to the main block portion and acts as the actual barrier. The roundish in plan view part of the spoon, which is also called Laffe or spoon bowl in the cutlery, is preferably designed approximately flat at the check valve. The connecting portion, which corresponds to the "stem" of the spoon, connects the locking main portion to the main body portion. Thus, a lightweight construction is achieved and the overall mass of the system is reduced.

It may, also further education, be provided on the check valve, a resilient portion which, particularly preferably, has a defined Federkostante. Thus, the locking portion may be resiliently and / or resiliently connected to the main body portion. It is particularly preferred when the "dipper stick" acts as the compliant and / or resilient element.

In other words, a fast camshaft phaser with check valves, for example in the vanes, as well as a pump connection and a tank connection in / at the central valve is proposed.

The invention will be described below with reference to several embodiments with reference to the accompanying figures. Show it:

1 a circuit diagram of a camshaft adjuster according to a first embodiment,

2 FIG. 2 shows a sectional view of the camshaft adjuster according to the first embodiment, transversely to a longitudinal axis of the camshaft adjuster, FIG.

3 and 4 each a sectional view of the camshaft adjuster according to the first embodiment along the longitudinal axis of the camshaft adjuster, wherein the sectional views are offset by an angle of approximately 30 ° about the longitudinal axis,

5 and 6 each a sectional view of the camshaft adjuster according to the first embodiment of a main valve along the longitudinal axis of the camshaft adjuster, wherein the sectional views are offset by the angle of approximately 30 ° about the longitudinal axis, and

7 a check double valve according to the first embodiment, and

8th a check double valve according to a second embodiment.

The figures are merely schematic in nature and are only for the understanding of the invention. The same or comparable elements are provided with the same reference numerals. Features of one embodiment may also be included in the other embodiments; So they are interchangeable.

A camshaft adjuster 1 A first embodiment of the invention is of the rotary piston type. The camshaft adjuster 1 extends along a longitudinal axis X and this longitudinal axis X defines a radial direction Y and a circumferential direction Z, see for example 2 and 3 ,

The camshaft adjuster 1 has a stator 2 , a rotor 3 , a main valve 4 and a valve control device 5 , The stator 2 is a drive component and has radially outside a toothing 6 which, for example, with a chain or a toothed belt (both not shown) can positively transmit a rotary power. The rotor 3 is an output component and is equipped with a camshaft 7 rotatably connected to a rotational performance between the phaser 1 and the camshaft 7 transferred to.

The stator 2 takes radially inside the rotor 3 on, and the rotor 3 radially inward takes the main valve 4 on. An inner contour 8th of the stator 2 and an outer contour 9 of the rotor 3 define a variety of work spaces 10 , which by rotor-fixed wings 11 in first pressure chambers 12 and second pressure chambers 13 be divided. The wings 11 are an example of a piston. The workrooms 10 are connected in parallel so that the first pressure chambers 12 and the second pressure chambers 13 are also connected in parallel. The first pressure chambers 12 and the second pressure chambers 13 become collectively called pressure chambers 14 designated. See in particular 2 ,

The main valve 4 , which may also be referred to as a central valve, has an inlet port P, a return port R, a drain port T and two working ports A, B. The main valve 4 is in 1 shown with a dashed frame and is particularly in the 5 and 6 clearly visible.

The main valve 4 is among other things from a proportional valve 15 , a main valve spring 16 and a return chamber 17 built up. The proportional valve 15 is a 3/4 proportional valve with three ways 18 and four ports, namely an internal intake port P ', and the drain port T and the working ports A and B. The internal port P' is connected to the return chamber 17 fluidly connected, which in turn with both the return port R and with the Inlet port P is fluidly connected. The current position of the proportional valve 15 is about the main valve spring 16 and the valve controller 5 adjustable, allowing free between the three ways 18 can be chosen. Instead of the proportional valve 15 A non-proportional 3/4 valve may also be used.

With the inlet port P is a central check valve 19 fluidly connected. The central check valve 19 leaves to the inlet port P through a fluid, whereas the central check valve 19 in the reverse direction, ie away from the inlet port P, blocks. The central check valve 19 is spring biased with a low threshold. Via the central check valve 19 is the inlet port P with a pressure source, such as a pump 20 , connected. The central check valve 19 can in the main valve 4 be integrated.

With the drain port T is a throttle 21 fluidly connected. The throttle 21 is a symbol for a reduction in the effective diameter of the fluidic connection of the drain port T with a pressure sink, such as a tank 22 or a suction port of a pump. The throttle 21 may be a separate component, such as a throttle component or an orifice member, or may have an integrated function in or on the main valve 4 , such as a narrow-section pipe or a diversion.

The working connection A is via respective working lines 23 for example, with the first pressure chambers 12 fluidly connected, and the working port B is via respective working lines 23 for example, with the second pressure chambers 13 fluidly connected.

The pressure chambers 14 are present in each case via a valve inlet 24 each with a check valve 25 fluidly connected. Here are the check valves 25 from the respective pressure chamber 14 arranged from passing. Thus, in the presence of a higher pressure in one of the pressure chambers 14 as the pressure in the return chamber 19 the fluid from the pressure chamber 14 to the return chamber 19 stream. The check valves 25 are biased at a low threshold.

Two check valves each 25 are via a present example, common, branched valve connection line 26 with the return port R of the main valve 4 fluidly connected. There are two check valves in each case 25 to a check double valve 37 summarized.

The three ways 18 are a first way 27 , a second way 28 and a third way 29 , The first way 27 Also referred to as neutral position, the working ports A, B, the internal inlet port P 'and the drain port T blocks each. The second way 28 fluidly connects the internal inflow port P 'via, for example, the working port A with the first pressure chambers 12 and fluidly connects the drain port T via the other working port, for example, the working port B, with the second pressure chambers 13 , The third way 29 fluidly connects the internal inflow port P 'via, for example, the working port B with the second pressure chambers 13 and fluidly connects the drain port T via the other working port, for example, the working port A, with the first pressure chambers 12 , The ways 18 can also be referred to as valve positions.

The following is on the adjustment of the camshaft adjuster 1 received. It is assumed for the sake of simplicity that an adjustment with increasing volume of the pressure chambers 12 and with decreasing volume of the pressure chambers 13 is sought. It becomes between a TA enterprise, a CTA alone enterprise with not driven pump 20 and a CTA Zuschaltbetrieb with driven pump 20 distinguished.

In TA mode, the proportional valve 15 in the way 28 switched, therefore is due to pressure chamber 12 the high pressure of the pump 20 and is located at the pressure chamber 13 the low pressure of the tank 22 at. Therefore, the hydraulic fluid in the pressure chamber 12 conveyed in, and is the hydraulic fluid from the pressure chamber 13 sponsored out. The wings are moving 11 in the workrooms 10 and the rotor is moving 3 relative to the stator 2 ,

In CTA alone operation, the proportional valve 15 also in the way 28 switched so that the first pressure chambers 12 with the return chamber 17 are fluidically connected and the second pressure chambers 13 with the throttle 21 are fluidically connected. Because the pump 20 is not driven, the first pressure chambers 12 not supplied with fluid, can also increase the volume of the second pressure chambers 13 do not decrease and no fluid flows or runs through the throttle 21 , If now a torque over the second pressure chambers 13 is transmitted because of the alternating moments in the second pressure chambers 13 a higher pressure than in the return chamber 17 before, ie it is in the second pressure chambers 13 an overpressure. The second pressure chambers 13 associated check valves 25 open a fluid passage and the fluid flows out of the second pressure chambers 13 over the second pressure chambers 13 associated check valves 25 and the return chamber 17 in the first pressure chambers 12 , The wings are moving 11 in the workrooms 10 and the rotor is moving 3 relative to the stator 2 , The fluid gets out of the pressure chambers 13 pressed to the extent as the first pressure chambers 12 increase, and there is no fluid flowing through the drain port T. It could further developing an additional, switchable shut-off valve between the drain port T and the tank 22 be provided. The CTA stand-alone operation provides a redundant safety measure, also known as a "safe-fail" measure, in the event of a failure of the pump 20 represents.

In the CTA connection operation, the camshaft adjuster 1 operated in TA mode. If now a torque or alternating torque on the second pressure chambers 13 is transmitted, the pressure in the second pressure chambers increases 13 , When the pressure in the second pressure chambers 13 higher than the pressure in the return chamber 17 will open the second pressure chambers 13 associated check valves 25 or they allow for a fluid passage. Because of this, in addition to that flows from the pump 20 to the first pressure chambers 12 conveyed fluid, the fluid from the second pressure chambers 13 in the first pressure chambers 12 , At the same time, the fluid flows out of the second pressure chambers 13 over the throttle 21 to the tank 22 , The throttle 21 however, limits the amount of to the tank 22 flowing fluid and maintains the pressure in the second pressure chambers 13 at least sufficiently upright, so that the CTA Zuschaltbetrieb works particularly reliable. Especially in view of the short time interval during which alternating torque typically occurs, the throttle is 21 sufficient for approximate pressure maintenance.

In CTA-Zuschaltbetrieb the camshaft adjuster 1 consequently adjust faster or at least as fast as in TA mode. It is preferred that the phaser 1 operated in the CTA connection operation.

In other words, it will be described if there is an overpressure in the pressure chambers 14 occurs, which is caused by the alternating moments that the respective pressure chambers 14 associated check valves 25 active and leave the overpressure to the return chamber 17 or to the inlet port P of the main valve 4 by. Because of the main valve 4 The overpressure can not come from the main valve 4 to the pump 20 escape, and it is by the overpressure, the fluid according to the chosen path 28 into the intended pressure chambers 14 directed. The CTA single mode and the CTA connection mode can enable rapid adjustment at all operating points (in the presence of alternating torques).

From the above description it is clear that the check valves 25 , which the pressure chambers 14 are assigned, can be referred to as pressure relief valves of the check chambers. This does not imply that the check valves 25 in all cases have a pressure chamber pressure limiting effect.

Incidentally, it is such that, if the alternating moments an overpressure in the pressure chambers 14 arises, in which the fluid should intentionally flow, so this pressure is through the respective working lines 23 , the chosen path 28 , the return chamber 17 and the valve connection line 26 to the backs of the check valves 25 directed. Therefore, they do not open due to lack of pressure difference and bias. It is therefore in this case a hydraulic support of the pressure chambers to be enlarged 14 guaranteed. An adjustment against the desired adjustment direction is reliably prevented without the CTA Zuschaltbetrieb to prevent.

Below are some peculiarities of the structure of the camshaft adjuster 1 separately explained according to the first embodiment.

From the 2 not just the arrangement of stator 2 , Rotor 3 and main valve 4 clearly, but it can also be seen that a positioning of the check valves 25 in the wings 11 Offers advantages. So can namely a check valve 27 for receiving the check valves 25 or the check double valves 37 in the wings 11 be simply formed by a bore, a milling, a broaching or the like in the direction of the longitudinal axis X. Furthermore, the valve leads 24 are formed by a bore tangential to the circumferential direction Z in the wings. Finally, the valve connection lines 26 through a bore along the radial direction Y in the rotor 3 and in the wings 11 be formed. All of these holes are easy to position, easy to operate and easy to control before assembly. Intersecting blind holes are avoided, which could lead to rejects.

From the 3 to 6 is the relative arrangement of the terminals P ', P, T, R, A and B, and the working lines 23 and the valve connection lines 26 further clarified. It should be noted that the 5 a section of the 3 shows enlarged, and the 6 according to a section of the 4 shows.

For example, the lines 23 . 26 arranged as follows in the first embodiment. There is one for each of the four workrooms working line 23 to the respective first pressure chamber 12 preferably axially camshaft side in the rotor 3 intended. The respective valve connection line 26 to the check valves 25 in the wing 11 between the two respective pressure chambers 14 is hereby preferably axially approximately centrally in the rotor 3 intended. The respective work management 23 to the respective second pressure chamber 13 Finally, it is preferably axially valve control unit side in the rotor 3 intended. It is preferable to all these lines 23 . 26 Also provided spaced in the circumferential direction Z, namely so that the working lines 23 each just next to the wing 11 in the respective pressure chamber 14 lead. This ensures that the structure of the rotor 3 is not weakened by an excessive occurrence of holes, recesses or penetrations in the sense of a notch effect.

For example, the main valve or central valve 4 which is centrally located in the rotor 3 is arranged in a main valve receptacle or central valve receptacle 28 in the rotor 3 added. The main valve intake 28 has a hollow cylindrical shape, and is made for example as a bore. At the main valve intake 28 are three ring channels 29 educated. Each of the ring channels 29 has a hollow cylindrical, to the main valve receptacle 28 open form, with the working lines 23 and the valve connection line 26 each one of the ring channels 29 branch. Through the ring channels 29 is achieved that the main valve 4 independent of angle, allowing the assembly of the camshaft adjuster 1 is simplified.

The following is an exemplary design of the check double valve 37 and the check valves 25 received.

The non-return double valve 37 The first embodiment is a thin-walled part, preferably a sheet steel part made of sheet steel, and has a main body portion 30 as well as two lock sections 31 , The lock sections 31 are spoon-shaped and each comprise a main block portion 32 and a connection section 33 , Here is the entire check double valve 37 set up in the check valve receptacle 27 to be included. The non-return double valve 37 is designed such that the main body portion 30 positive fit with the check valve receptacle 27 cooperates, so that the check double valve 37 Operationally in the check valve receptacle 27 sitting. By way of example, an alternative or additionally acting interference fit from the main body portion 30 and the check valve receptacle 27 proposed.

The main block sections 32 are designed so that these the respective valve leads 24 completely and fluidly seal tightly in the manner of a check valve. In particular, the respective main block section 32 preferably a larger diameter than the respective valve lead 24 on. The connecting sections 33 connect the main block sections 32 with the main body section 30 , In this case, the respective connection section causes 33 preferably a resilient bias, which the main block portion 32 up to a predetermined threshold value of overpressure in the respective pressure chamber 14 in a the respective valve lead 24 hold blocking position or position.

The main body section 30 and one locking section each 31 form a check valve 25 , By providing only a lock section 31 could analogously be a check valve 25 and a kickback single valve are formed.

The main body section 30 is preferably bent, wherein the bend has a longitudinal axis U and thus also a radial direction V and a circumferential direction W of the check double valve 37 Are defined. Approximately preferably centrally along the longitudinal axis U protrude in the first embodiment of the main body portion 30 parallel to a radial direction V, the locking portions 31 from. This is in 7 to recognize. The non-return double valve 37 has two in a closure or opening direction parallel to each other extending spoon-shaped locking portions 31 on. This above-described design of the check double valve 37 is easy to manufacture by means of a punching step and a bending step.

The longitudinal axis U of the check double valve 37 is preferably approximately parallel to the longitudinal axis X of the camshaft adjuster 1 , The main body section 30 extends along the longitudinal axis U of the check valve 25 over the entire extension / length / depth of the check valve receptacle 27 , so that the respective main block section 32 in the direction of the longitudinal axes U, X to the position of the valve lead 24 is fixed. It is, for fluidic reasons, only preferred that the valve leads 24 and thus the main block sections 32 are arranged centrally along the longitudinal axes U, X.

A second embodiment of the invention will be described below. The same elements are given the same reference numerals and will not be described again. In the second embodiment, the check double valves 37 in terms of the arrangement and shape of the barrier sections 31 designed differently.

In the second embodiment, the connecting portions extend 31 substantially along the longitudinal direction U. The connecting sections 31 protrude with a first connecting section 34 first from the main body section 30 parallel to a radial direction V from. These are each followed by a second connecting section 35 which may also be referred to as an angling. This is followed by a third connecting section in each case closes 36 at, which extends along the longitudinal direction U, and the respective main locking portion 32 stores, so that the main block section 32 ultimately with the main body section 30 connected is. The non-return double valve 37 According to the second embodiment has two in a closing or opening direction parallel to each other extending spoon-shaped locking portions 31 on.

About the total length of the three connecting sections 34 . 35 . 36 can the spring preload to lock the respective valve lead 24 by means of the main block section 32 be determined.

LIST OF REFERENCE NUMBERS

1

 Phaser

2

 Stator or drive component

3

 Rotor or driven component

4

 Main valve or central valve

5

 Valve controller

6

 gearing

7

 camshaft

8th

 Inner contour of the stator

9

 Outer contour of the rotor

10

 working space

11

 Wing or piston

12

 first pressure chamber

13

 second pressure chamber

14

 pressure chambers

15

 proportional valve

16

 Main valve spring

17

 Return chamber

18

 Way or valve position

19

 Central check valve

20

 pump

21

 throttle

22

 tank

23

 working line

24

 valve supply line

25

 check valve

26

 Valve connecting line

27

 Check valve receptacle

28

 Main valve intake or central valve intake

29

 annular channel

30

 Main body portion

31

 blocking portion

32

 Blocking main section

33

 connecting portion

34

 first connection section

35

 second connecting portion

36

 third connecting section

37

 Check valve Double

A

 working port

B

 working port

P

 inflow connection

R

 Return connection

T

 drain connection

U

 Longitudinal axis of the check double valve

V

 Radial direction of the check double valve

W

 Circumferential direction of the check double valve

X

 longitudinal axis

Y

 radial direction

Z

 circumferentially

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 102005052481 A1 [0010, 0010]
• DE 112011103133 T5 [0012, 0013, 0013]

Claims (10)

Hydraulic camshaft adjuster ( 1 ) with a drive component ( 2 ), with a driven component ( 3 ), with a workspace ( 10 ) a piston ( 11 ) in two pressure chambers ( 14 ) so divided that by a relative movement of the piston ( 11 ) in the workspace ( 10 ) a relative movement between the drive component ( 2 ) and the output component ( 3 ) and with a main valve ( 4 ), the main valve ( 4 ) an inlet connection (P) for the fluidic connection to a pressure source, a discharge connection (T) for the fluidic connection to a pressure sink and two working connections (A, B), one of which is in each case one of the two pressure chambers ( 14 ), wherein the main valve ( 4 ) for selectively fluidically connecting the inlet port (P) with one of the two working ports (A, B) and the drain port (T) with the other of the two working ports (B, A) or for fluidic locking of both working ports (A, B) characterized in that both pressure chambers ( 14 ) via in each case such a configured and arranged non-return valve ( 25 ) are fluidically connected to the inlet port (P) that each at an overpressure in the respective pressure chamber ( 14 ) allows fluid passage to the feed port (P). Camshaft adjuster ( 1 ) according to claim 1, characterized in that the camshaft adjuster ( 1 ) is configured axial piston type, wherein the drive component ( 2 ) and the output component ( 3 ) with the piston ( 11 ) are connected for effecting the relative movement in each case via a helical toothing, and wherein the piston ( 11 ) is axially movable. Camshaft adjuster ( 1 ) according to claim 1, characterized in that the camshaft adjuster ( 1 ) is designed like a rotary piston, wherein the drive component ( 2 ) is a stator and the output component ( 3 ) is a rotor, wherein the piston ( 11 ) for effecting the relative movement about a common longitudinal axis (X) of the drive component ( 2 ) and output component ( 3 ) is rotatable, and wherein the piston ( 11 ) is preferably designed as a rotor-fixed wing. Camshaft adjuster ( 1 ) according to claim 2, characterized in that a check valve ( 25 ) or both check valve ( 25 ) in the wing ( 11 ) are arranged. Camshaft adjuster ( 1 ) according to one of claims 2 or 3, characterized in that a valve lead ( 24 ) in the wing ( 11 ) is formed, which one of the pressure chambers ( 14 ) with the respective check valve ( 25 ) fluidly connects. Camshaft adjuster ( 1 ) according to one of claims 1 to 5, characterized in that at least one of the check valves ( 25 ) with the inlet connection (P) of the main valve ( 4 ) by means of at least one valve connection line ( 26 ) is fluidly connected. Camshaft adjuster ( 1 ) according to one of claims 1 to 6, characterized in that a central check valve ( 19 ) at the inlet connection (P) from the pressure source ( 20 ) to the inlet connection ( 20 ) is arranged through, and wherein the check valves ( 25 ) downstream of the central check valve ( 19 ) to the feed port (P). Camshaft adjuster ( 1 ) according to one of claims 1 to 7, characterized in that at least one check valve ( 25 ) is resiliently biased. Camshaft adjuster ( 1 ) according to one of claims 1 to 8, characterized in that the fluidic connection of the pressure chambers ( 14 ) to the pressure sink ( 22 ) with a separate throttle ( 21 ) and / or that the effective diameter of the fluidic connection of the pressure chambers ( 14 ) with the pressure sink ( 22 ) smaller than the effective diameter of the fluidic connection of the pressure chambers ( 14 ) via the respective check valve ( 25 ). Camshaft adjuster ( 1 ) according to one of claims 1 to 9, characterized in that the check valve ( 25 ) is designed as a sheet metal part and a main body portion ( 30 ) and at least one spoon-shaped lock section ( 31 ) having.

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