DE102015116024A1 - Schwenkmotorversteller a camshaft - Google Patents

Abstract

The invention relates to a Schwenkmotorversteller for a camshaft having a rotor (9) and a stator (2) and a hydraulic valve (17) for positioning the rotor (9) relative to the stator (2), wherein for locking the relative to the stator (2 ) is formed pivotable rotor (9) with the stator (2) a locking device (18), and wherein between the stator (2) and the rotor (9) variable pressure chambers (10) are formed, and wherein the hydraulic valve (17) has a first working port (A), a second working port (B), a supply port (P) and a tank port (T), which are hydraulically communicating with each other for hydraulic flow through the pressure chambers (10), and wherein the locking device (18) by means of Hydraulic valve (17) can be acted upon hydraulically. According to the locking device (18) via the supply connection (P) can be acted upon for unlocking or locking.

Description

The invention relates to a Schwenkmotorversteller a camshaft according to the preamble of patent claim 1.

Schwenkmotorversteller serve to adjust a camshaft relative to a crankshaft of an internal combustion engine. The camshaft is connected to the crankshaft by means of a drive element. This drive element may be a gear, a drive chain or a drive belt. With the help of the camshaft opening and closing times of valves of the internal combustion engine are fixed, which are not necessarily with an optimized, i. efficient and efficiency-optimized operation of the internal combustion engine. To achieve optimized operation of the internal combustion engine, the opening and closing times are dependent on the load and / or the speed of the internal combustion engine to adapt. This adaptation can be achieved with the help of a Schwenkmotorverstellers.

The Schwenkmotorversteller is hydraulically controlled and uses as hydraulic fluid in the lubricating oil circuit of the engine existing lubricating oil, which flows through the Schwenkmotorversteller with the help of a Schwenkmotorversteller associated hydraulic valve.

Hydraulic valves for Schwenkmotorenversteller a camshaft are well known. The hydraulic valves have a valve piston, which is axially movable in a valve housing of the hydraulic valve. Usually, a first working connection, a second working connection and a supply connection are formed on the valve housing. The first working connection and the second working connection are connected to the swivel motor adjuster and via these connections a hydraulic fluid can be conveyed both into the hydraulic valve and out of the hydraulic valve. For supplying the hydraulic valve with the hydraulic fluid delivered by means of a conveyor, the valve housing has the supply connection. The hydraulic fluid can flow through the hydraulic valve differently with the aid of a flow-through channel system of the valve piston.

In a typical Schwenkmotorversteller a locking device is arranged to allow under certain operating conditions of the Schwenkmotorverstellers and the internal combustion engine, a rotational lock of a rotor of the Schwenkmotorverstellers to a stator of the Schwenkmotorverstellers. A known locking device comprises a locking bolt and a return element to clamp the bolt in a conventionally hardened seat so that the rotor is locked with respect to the stator fixedly connected to a pulley or a sprocket of the internal combustion engine.

The object of the present invention is to provide a Schwenkmotorversteller for a camshaft having an alternative locking device.

The object is achieved by a Schwenkmotorversteller for a camshaft with the features of claim 1. Advantageous embodiments with expedient and non-trivial developments of the invention are specified in the respective subclaims.

The inventive Schwenkmotorversteller for a camshaft comprises a rotor and a stator and a hydraulic valve for positioning the rotor relative to the stator. For locking the relative to the stator pivotable rotor with the stator, a locking device is formed. Changeable pressure chambers are configured between the stator and the rotor, the hydraulic valve having working connections, a supply connection and a tank connection for the hydraulic flow through the pressure chambers communicating hydraulically with one another. The locking device can be hydraulically acted upon by means of the hydraulic valve. According to the invention, the locking device can be acted upon by the supply connection for unlocking or locking. The advantage is that the locking device can be actuated exclusively by means of a pressure present in the already existing supply connection, wherein an already existing supply channel of the supply connection in the rotor can be used.

Advantageously, the locking or unlocking is controllable.

In a further refinement, a control valve is arranged in a pressure line through which the supply connection can flow. Thus, there is the possibility of locking depending on a control profile, which is, for example, map-controlled, bring about.

In a further embodiment, the locking device is designed in the form of a displaceable adjusting bolt arranged in the rotor, wherein the adjusting bolt by means of pressurization from the supply connection in a rotor formed in the first receiving opening for locking or unlocking is displaceable in order with the stator a shape and / or force-locking connection to bring or solve this.

The control valve may be an electromagnetic or pneumatic or mechanical control valve. It is preferable to use an electromagnetic control valve because of its generally shorter displacement time or shorter reaction time than other control valves.

If the control valve is a 3/2-way switching valve, there is the advantage that via a third connection of the control valve, the hydraulic fluid flowing out of the pressure line can be conducted, for example, into a crankcase of the internal combustion engine or into a separate tank connection.

Compared to a control valve designed in the form of a 3/2-way switching valve, a 2/2-way switching valve is more compact. If leakage for safe venting are sufficient, a 2/2-way switching valve is preferred to use as a control valve.

With the help of the control valve unlocking can be done in two different ways. One way is the admission of the control valve for unlocking. If it is, for example, an electromagnetic control valve, in this context, the admission means energization of the control valve. The advantage is that due to the applied continuous current flow of the control valve, a so-called "fail-safe" function is ensured.

The second way is the admission of the control valve for locking. This means that the control valve is acted upon only, or energized in the case of an electromagnetic control valve when a lock is to take place. An advantage is that it is automatically unlocked before starting the engine.

In a further embodiment, the control valve is designed as a bistable switching valve. Designed as a bistable switching valve, the control valve requires two independent control signals. The advantage of the bistable switching valve is that it remains in the position in which it last received a control signal.

Further advantages, features and details of the invention will become apparent from the following description of preferred embodiments and from the drawing. The features and feature combinations mentioned above in the description as well as the features and feature combinations mentioned below in the description of the figures and / or in the figures alone can be used not only in the respectively specified combination but also in other combinations or in isolation, without the scope of To leave invention. Identical or functionally identical elements are assigned identical reference numerals. For reasons of clarity, it is possible that the elements are not provided with reference numbers in all figures, but without losing their assignment. Show it:

1 1 shows a longitudinal section of a first exemplary embodiment of a swivel motor adjuster according to the invention with a hydraulic valve and with a schematically illustrated control valve,

2 in a schematic representation of the control valve of the Schwenkmotorverstellers a second embodiment,

3 in a schematic representation of the control valve of the Schwenkmotorverstellers a third embodiment, and

4 in a schematic representation of the control valve of the Schwenkmotorverstellers a fourth embodiment.

An inventive Schwenkmotorversteller 1 is like in 1 shown constructed. It allows during operation of an internal combustion engine, not shown, to bring about a change of opening and closing times of gas exchange valves of the internal combustion engine. This is done with the help of Schwenkmotorverstellers 1 a relative angular position of a camshaft, not shown, of the internal combustion engine with respect to a crankshaft of the internal combustion engine, not shown, changed continuously, wherein the camshaft is rotated relative to the crankshaft. By turning the camshaft, the opening and closing times of the gas exchange valves are shifted so that the internal combustion engine brings its optimum performance at the respective speed.

The Schwenkmotorversteller 1 has a cylindrical stator 2 on, the rotation with a drive wheel 3 the camshaft is connected. In the embodiment, the drive wheel 3 a pulley over which a non-illustrated belt is guided as a drive element. The drive wheel 3 but may also be a sprocket over which a drive chain is guided as a drive element. About this drive element and the drive wheel 3 is the stator 2 Driven with the crankshaft.

The stator 2 has a cylindrical stator base body 4 on, on which on the inside 5 are not radially inwardly extending webs formed at regular intervals, such that between each two adjacent webs a gap 6 is formed. In this space 6 becomes a pressure medium, generally a hydraulic fluid, by means of a hydraulic valve 17 introduced controlled.

In the gap 6 protruding is a wing 7 positioned, which on a rotor hub 8th a rotor 9 of the swivel motor adjuster 1 is arranged. The number of spaces 6 accordingly, the rotor hub 8th a number of wings 7 on.

With the help of the wings 7 are thus the spaces between them 6 each in a first pressure chamber 10 and divided into a second pressure chamber, not shown. To reduce a pressure loss in the first pressure chamber 10 and the second pressure chamber are the webs with their first end faces not shown in detail on a non-illustrated outer surface of the rotor hub 8th formed tight fitting. Likewise, the wings are 7 with their second end faces 11 sealingly on one of the outer lateral surface oppositely positioned inner wall 12 of the stator base body 4 at.

The rotor 9 is non-rotatable with the camshaft of the engine via a cylindrical camshaft adapter 19 connected. To change the angular position between the camshaft and the crankshaft, the rotor becomes 9 relative to the stator 2 around a rotation axis 15 of the Schwenkmotorverstellers 1 turned. For this purpose, depending on the selected direction of rotation, the pressure medium in the first pressure chamber 10 or pressurized in the second pressure chamber while the second pressure chamber and the first pressure chamber, respectively 10 is relieved.

The discharge takes place with the help of a non-illustrated tank connection T, which is open for relief. To realize a compact design, it may be a single for the first pressure chamber 10 and the second pressure chamber accessible tank port T act.

For locking a position of the stator 2 and the rotor 9 , which ensures a corresponding positioning of the camshaft relative to the crankshaft at a start of the internal combustion engine, is a locking device 18 of the Schwenkmotorverstellers 1 provided in the form of a center lock. This means that in the locking position, all between the between the stator 2 and the rotor 9 trained pressure chambers 10 have almost the same size or the stator 2 the wings 7 not touched at their radially extending walls.

So that the rotor 9 opposite the stator 2 is rotated in the clockwise direction, using the hydraulic valve 17 radial first hub bores 13 pressurized, which over the circumference of the rotor hub 8th arranged regularly distributed. For rotation of the rotor 9 opposite the stator 2 counterclockwise with the help of the hydraulic valve 17 radial second hub bores 14 pressurized, which also over the circumference of the rotor hub 8th are distributed, these second hub bores 14 axially from the first hub bores 13 are positioned at a distance.

The rotor 9 at least partially comprises the hydraulic valve 17 , The hydraulic valve 17 is similar to a cartridge valve and has a valve body 20 on, within which a valve piston 21 is arranged axially displaceable.

For axial displacement of the valve piston 21 along a coaxial to the axis of rotation 15 trained valve axis 16 , Is a remote from the engine trained first end face 22 of the valve piston 21 closed, leaving a pestle 23 at this first end face 22 can be present. With the help of an electromagnetic linear actuator 24 becomes the valve piston 21 over the pestle 23 positioned. An energization of the linear actuator 24 leads to the axial displacement of the valve piston 21 in the direction of the internal combustion engine, one at a second end face 25 of the valve piston 21 , which from the first end face 22 is formed away from, attached retaining element 26 a retention force on the valve piston 21 exerts, against which the valve piston 21 to move.

For secure sealing of the Schwenkmotorverstellers 1 to hydraulic fluid leakage is at its the linear actuator 24 facing trained end an adjuster cover 27 of the Schwenkmotorverstellers 1 added.

The retaining element 26 formed in this embodiment in the form of a helical compression spring is at its the valve piston 21 facing end formed on the second end face 25 fixed and supported with his from the valve piston 21 facing away from the end of a valve housing 20 designed ring surface 28 from.

The bush-like valve housing 20 has a first working connection A, a second working connection B and a supply connection P. The first working port A, the second working port B and the supply port P are a first channel 29 , a second channel 30 or a third channel 31 assigned, which are each connected to the terminals. The channels 29 . 30 . 31 are a housing wall 32 of the valve housing 21 formed in the radial direction completely penetrating.

The supply port P is designed for connection to an oil pump, not shown, so that the hydraulic valve 17 with the hydraulic fluid, which is oil in this embodiment, can be supplied. In the flow path of the Supply port P is a check valve 33 formed, which is a return flow of the hydraulic fluid from the hydraulic valve 17 prevented in the supply port P.

The locking device 18 has an adjusting bolt 34 up in one in the wing 7 trained first receiving opening 35 slidably received. For locking the rotor 9 with the stator 2 is one with the stator 2 firmly connected locking disc 36 at the linear actuator 24 facing trained side of the rotor 9 arranged at its the first receiving opening 35 facing side surface 37 a second receiving opening 38 has, in which the adjusting bolt 34 can be pushed into it. In this embodiment, a positive connection between the locking disc 36 , or due to the fixed connection of the stator 2 with the locking disc 36 with the stator 2 and the rotor 9 produced.

A control of the adjusting bolt 34 takes place hydraulically, being assigned to the supply port P, in the rotor 9 arranged fourth channel 39 a fifth channel 40 branching off in the rotor 9 is formed, in the first receiving opening 35 empties.

For controlling the adjusting bolt 34 is a control valve 41 with a pressure line 42 the Schwenkmotorversteller 1 associated with a pressurizable connection 43 in the form of a bore between the control valve 41 and the fifth channel 40 in the camshaft adapter 19 is designed.

The adjusting bolt 34 is cylindrical, comprising a shaft 44 and a head 45 , The confluence of the fifth channel 40 in the first receiving opening 35 is between the head 45 and the locking disc 36 arranged. Furthermore, the adjusting bolt 34 a third receiving opening 46 on which the adjusting bolt 34 at least partially penetrating and a restoring element 47 , preferably in the form of a coil spring, supporting receives.

At one of the locking disc 36 turned away end of the first receiving opening 35 is a lid-like closure 48 with a discharge opening, not shown, the first receiving opening 35 closing position. The reset element 47 relies on his from the adjusting bolt 34 opposite end to this closure 48 from.

In this first embodiment, the control valve 41 energized when the adjusting bolt 34 from the locking disc 36 is removed, in other words, the second receiving opening 38 releases and towards the lock 48 with the help of the fifth channel 40 applied hydraulic pressure is pressed. Because the head 45 the lock 48 may face due to the fifth channel 40 applied pressure a force on the head 45 attack him in the direction of the shutter 48 presses or pushes. About the discharge opening can be between the head 45 and the closure 48 existing air escape, so that during the displacement of the adjusting bolt 34 no additional force is needed to compress the air.

The control valve 41 is formed in the first embodiment in the form of a 3/2-way switching valve, wherein a first valve port 49 with the pressure line 42 hydraulically connected, a second valve port 50 is hydraulically connected to the supply line P and a third connection 51 with a discharge line 52 hydraulically connected.

The discharge line 52 is connected to a crankcase, not shown, of the internal combustion engine. Likewise, however, it could also be connected to a separate channel of the tank connection T.

In 2 is a control valve 41 the Schwenkmotorverstellers invention 1 shown in a second embodiment. The Schwenkmotorversteller 1 is basically according to the Schwenkmotorverstellers 1 of the first embodiment, however, the control valve 41 formed in the form of a 2/2-way switching valve. The illustrated control valve 41 is shown in the de-energized connection state. In this case, the first valve port 49 and the second valve port 50 separated and the adjusting bolt 34 is in the second receiving opening 38 taken in sections.

Likewise, as described in the first embodiment, the control valve 41 switched so that it is then energized when a release is to be performed. Ie. the energization of the control valve 41 takes place as long as the rotor 9 not rotatable with the stator 2 should be connected. To unlock the control valve 41 energized, an adjustment of the control valve 41 is due to the energization brought about, such that it is for connection of the first valve port 49 with the second valve port 50 is positioned.

3 shows a control valve 41 the Schwenkmotorverstellers invention 1 in a third embodiment. It is also designed in the form of a 3/2-way switching valve, although in the illustrated de-energized position of the control valve 41 , the first valve connection 49 with the second valve port 50 communicates. Thus lies on the adjusting bolt 34 , or at the head 45 the pressure from the supply port P to which the adjusting bolt 34 against the force of the return element 47 in the direction of the closure 48 suppressed. That means the control valve 41 then to energize, if a lock should take place.

When energized, the control valve 41 adjusted so that the first valve port 49 and the second valve port 50 are separated from each other. This will be the fifth channel 40 not supplied from the supply port P with hydraulic fluid and a restoring force of the return element 47 is sufficient around the adjusting bolt 34 in the second receiving opening 38 to push.

In 4 is a control valve 41 the Schwenkmotorverstellers invention 1 shown in a fourth embodiment. Also this control valve 41 is designed as a 2/2-way switching valve, which, like the control valve 41 of the third embodiment, then energized when a lock is to take place. Thus, when energizing the control valve 41 the first valve connection 49 and the second valve port 50 disconnected, leaving no supply to the fifth channel 40 with hydraulic fluid from the supply port P and the adjusting bolt 34 with the help of the return element 47 in the second receiving opening 38 at least partially included.

The control valve 41 The embodiments shown could also be designed as a so-called bistable valve, which must be present for its operation two external signals.

Claims (11)

Swivel motor adjuster for a camshaft, with a rotor ( 9 ) and a stator ( 2 ) and a hydraulic valve ( 17 ) for positioning the rotor ( 9 ) relative to the stator ( 2 ), wherein for locking the relative to the stator ( 2 ) pivotable rotor ( 9 ) with the stator ( 2 ) a locking device ( 18 ) is formed, and wherein between the stator ( 2 ) and the rotor ( 9 ) variable pressure chambers ( 10 ) are formed, and wherein the hydraulic valve ( 17 ) comprises a working ports (A, B), a supply port (P) and a tank port, which for hydraulic flow through the pressure chambers ( 10 ) are hydraulically communicating with each other, and wherein the locking device ( 18 ) by means of the hydraulic valve ( 17 ) is hydraulically acted upon, characterized in that for unlocking or locking the locking device ( 18 ) is designed to be acted upon via the supply connection (P). Schwenkmotorversteller according to claim 1, characterized in that the unlocking or locking is controllable. Schwenkmotorversteller according to claim 1 or 2, characterized in that in a through-connected to the supply port (P) pressure line ( 42 ) a control valve ( 41 ) is arranged. Schwenkmotorversteller according to any one of the preceding claims, characterized in that the locking device ( 18 ) in the form of a rotor ( 9 ) arranged displaceable adjusting bolt ( 34 ) is formed, wherein the adjusting bolt ( 34 ) by means of a pressurization from the supply connection (P) in one in the rotor ( 9 ) formed first receiving opening ( 35 ) is displaceable for locking or unlocking in order to engage with the stator ( 2 ) bring about a positive and / or non-positive connection or to solve this. Schwenkmotorversteller according to claim 4, characterized in that (for acting on the locking bolt 34 ) a fifth channel ( 40 ) in the rotor ( 9 ) is formed, which of one in the rotor ( 9 ) and the supply port (P) associated fourth channel ( 39 ) is branched off and into the first receiving opening ( 35 ) opens. Hydraulic valve according to one of claims 3 to 5, characterized in that the control valve ( 41 ) is an electromagnetic or pneumatic or mechanical control valve. Hydraulic valve according to one of claims 3 to 6, characterized in that the control valve ( 41 ) is a 3/2-way switching valve. Hydraulic valve according to one of claims 3 to 6, characterized in that the control valve ( 41 ) is a 2/2-way switching valve. Hydraulic valve according to one of claims 3 to 8, characterized in that the control valve ( 41 ) Is designed to unlock acted upon. Hydraulic valve according to one of claims 3 to 8, characterized in that the control valve ( 41 ) is designed to act upon locking. Hydraulic valve according to one of claims 3 to 10, characterized in that the control valve ( 41 ) is a bistable control valve.

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