DE102021200218A1 - sliding cam arrangement - Google Patents

Abstract

The present invention relates to a sliding cam arrangement, comprising a supporting shaft (1) with a longitudinal axis (L) of the supporting shaft and at least one sliding cam (2) mounted on the supporting shaft (1) in a rotationally fixed and axially displaceable manner, the sliding cam arrangement being equipped with a latching device (3), which is set up to releasably fix the sliding cam (2) in a first axial position and at least one second axial position, the latching device comprising a latching recess (31) and a latching element-spring combination with a latching element (33), the latching recess ( 31) has at least partially a first track (B1) and at least a second track (B2) for the latching element (33).

Description

The present invention relates to a slide cam assembly according to the preamble of claim 1.

Sliding cam assemblies of the aforementioned type are, for example, from DE 10 2004 011 586 A1 , DE 10 2011 084 043 A1 and DE 10 2009 005 731 A1 known.

the DE 10 2004 011 586 A1 describes, for example, a slide cam assembly with a latch for the slide cam. The locking device consists of a locking element arranged in the camshaft bearing, which engages in locking grooves machined into the cam carrier. In the case of a cam carrier with two cams, each of which has two cam tracks, two axially adjacent locking grooves are required in the cam carrier, in which the locking element engages.

the DE 10 2011 084 043 A1 describes a slide cam assembly with a locking device. For the sliding cam arrangement, it is provided here that the direction of the force component or the resulting force component of the locking device or devices is selected such that the backlash between the base shaft and the sliding cam in the end region of the base circle phase is eliminated as seen in the direction of rotation.

the DE 10 2009 005 731 A1 describes a sliding cam arrangement with a detent device in which it is provided that the bore is a through bore in which two spring-loaded detent balls are arranged.

With a detachable axial fixation of the sliding cam relative to the support shaft by means of a locking device, in particular by means of a ball-spring mechanism, only a part can be implemented as an axial force component due to the force of the spring in relation to the locking contour. In order to achieve the desired holding force, the spring force should be correspondingly high, which in turn leads to high contact forces or pressure and thus to wear on the locking contour and/or ball.

This is where the present invention comes in and sets itself the task of providing an improved sliding cam arrangement which overcomes the disadvantages outlined above, but at least brings about improvements. In particular, a sliding cam arrangement is to be provided whose latching device is subject to less wear.

According to the invention, this object is achieved by a sliding cam arrangement having the characterizing features of claim 1. The fact that the latching recess has, at least in sections, a first track and at least a second track for the locking element. As a result of this measure, a displacement of the locking element over two raceways and not over one raceway as in the prior art is realized or implemented. Accordingly, the forces can be divided between the at least two raceways, which reduces the surface pressure per raceway and thus also the wear. The wear and tear can be reduced with the configuration of the latching recess proposed above.

Further advantageous refinements of the proposed invention result in particular from the features of the dependent claims. The objects or features of the various claims can in principle be combined with one another as desired.

In an advantageous embodiment of the invention it can be provided that the locking element-spring combination comprises a spring and preferably a ball as the locking element.

In a further advantageous embodiment of the invention it can be provided that the latching element and the spring of the latching element-spring combination are accommodated in a radially aligned opening in the support shaft.

In a further advantageous embodiment of the invention, it can be provided that the latching recess has a latching recess base. In this case, the bottom of the latching recess essentially forms the contact area with the latching element.

In a further advantageous embodiment of the invention, it can be provided that the locking recess, in particular the locking recess base, in the direction of the longitudinal axis of the support shaft, a first area with a sloping locking recess base, a second area with a flat locking recess base, a third area with a rising locking recess base, a fourth area with a flat Has latching recess base, a fifth area with a sloping latching recess base, a sixth area with a flat latching recess base, and a seventh area with an increasing latching recess base. The base of the locking recess preferably has a wavy shape in a side view. The third to fifth area ultimately forms an increase that must be overcome by the latching element when the sliding cam is displaced between the two positions.

In a further advantageous embodiment of the invention, it can be provided that the fourth area is so small that the third area and fifth area merge into one another. The adjacent radii of the third and fifth areas preferably merge tangentially without forming a plateau between these areas. There is no plateau or the fourth area, ie the third area and the fifth area are directly opposite or merge into one another.

In a further advantageous embodiment of the invention, it can be provided that the second area and/or sixth area is configured by radii arranged tangentially and merging into one another.

In a further advantageous embodiment of the invention, it can be provided that the detent recess, in particular the detent recess base, has a distance A _K = 0 on the provided running surfaces from the contacting surface of the detent element, with all other surfaces of the detent recess, in particular the detent recess base, having a distance A _B > 0 have from the surface of the locking element. Using this criterion, diverse surface shapes of the locking recess, in particular the bottom of the locking recess, and the locking element are conceivable.

In a further advantageous embodiment of the invention, it can be provided that the latching recess, in particular the latching recess base, has a first bulge running in the axial direction, forming the first raceway, and a second bulge running in the axial direction, forming the at least second raceway. Such a configuration can be produced in a simple manner, for example if a sliding toothing which is provided in any case is also provided in this area.

Correspondingly, it can advantageously be provided that the sliding cam has a sliding toothing, with the bulge running in the axial direction forming the first track being formed by a first tooth of the sliding toothing and the second bulge running in the axial direction forming the at least second track a further tooth of the sliding toothing, in particular a further tooth arranged immediately next to the first tooth in the circumferential direction. The track or bulge can be advantageously formed by a sliding toothing that is present in any case. Such an embodiment can also have advantages in terms of production technology, in particular since the production capacities for the sliding toothing between the support shaft and the sliding cam are reserved in any case.

In a further advantageous embodiment of the invention, it can be provided that the bulge or tooth of the sliding toothing has, at least in sections, a straight or concave surface in the circumferential direction. The raceway or bulge or tooth of the sliding toothing can be unmachined or machined, in particular straight or concave. The advantage here is that the pressing load is reduced by dividing it into two contact lines.

In a further advantageous embodiment of the invention, it can be provided that the latching recess, in particular the latching recess base, is designed to be concave at least in sections. Suitable raceways can also be provided via a concave shape of the locking recess, in particular of the bottom of the locking recess, which can also be produced advantageously in terms of production technology.

In a further advantageous embodiment of the invention, it can be provided that that area of the latching recess which presses the latching element, in particular the ball, against the force of the spring in the direction of the longitudinal axis of the supporting shaft of the supporting shaft is equipped with the first track and the at least second track. In principle, the entire latching recess can be designed as proposed according to the invention. However, it is also conceivable that the tracks are only provided in the particularly affected area, in particular in the third to fifth area, which in particular forms an elevation that must be overcome by the locking element when the sliding cam is displaced between the two positions.

In a further advantageous embodiment of the invention it can be provided that the latching recess, in particular the latching recess bottom, has two tracks, in particular exactly two tracks.

• 1 eine Schiebenockenanordnung in einer geschnittenen perspektivischen Ansicht mit dem Schiebenocken in einer ersten axialen Position;
• 2 eine Schiebenockenanordnung in einer geschnittenen seitlichen Ansicht mit dem Schiebenocken in einer ersten axialen Position;
• 3 ein Schnitt A-A gemäß 2;
• 4 eine Schiebenockenanordnung in einer geschnittenen perspektivischen Ansicht mit dem Schiebenocken in einer Position zwischen der ersten axialen Position und der zweiten axialen Position;
• 5 eine Schiebenockenanordnung in einer geschnittenen seitlichen Ansicht mit dem Schiebenocken in einer Position zwischen der ersten axialen Position und der zweiten axialen Position;
• 6 ein Schnitt B-B gemäß 5;
• 7 eine Schiebenockenanordnung in einer geschnittenen perspektivischen Ansicht mit dem Schiebenocken in einer zweiten axialen Position;
• 8 eine Schiebenockenanordnung in einer geschnittenen seitlichen Ansicht mit dem Schiebenocken in einer zweiten axialen Position;
• 9 ein Schnitt C-C gemäß 8;
• 10 eine vergrößerte Darstellung der Rastaussparung mit einem Rastelement in einer Position gemäß 5;
• 11 eine Ausschnittvergrößerung gemäß Schnitt B-B gemäß 10 (konkave Form des Rastaussparungsbodens);
• 12 eine Ausschnittvergrößerung von 11 10 (konkave Form des Rastaussparungsbodens);
• 13 eine alternative Kontur der Rastaussparung bzw. des Rastaussparungsbodens (Ausbuchtung bzw. Schiebeverzahnungszahn als Laufbahn).

Further features and advantages of the present invention become clear from the following description of preferred exemplary embodiments with reference to the attached figures. show in it

• 1 a slide cam assembly in a cutaway perspective view with the slide cam in a first axial position;
• 2 a slide cam assembly in a sectional side view with the slide cam in a first axial position;
• 3 a section AA according to 2 ;
• 4 a slide cam assembly in a cutaway perspective view with the slide cam in a position between the first axial position and the second axial position;
• 5 a slide cam assembly in a sectional side view with the slide cam in a position between the first axial position and the second axial position;
• 6 a section BB according to 5 ;
• 7 a slide cam assembly in a cutaway perspective view with the slide cam in a second axial position;
• 8th a slide cam assembly in a sectional side view with the slide cam in a second axial position;
• 9 a section CC according to 8th ;
• 10 an enlarged view of the locking recess with a locking element in a position according to 5 ;
• 11 an enlargement according to section BB 10 (concave shape of the recess bottom);
• 12 an enlargement of 11 10 (concave shape of recess bottom);
• 13 an alternative contour of the detent recess or the detent recess base (bulge or sliding tooth as a raceway).

L

Tragwellenlängsachse

I - VII

erster bis siebter Bereich (Rastaussparung)

B1

erste Laufbahn (Ausbuchtung, Schiebeverzahnungszahn)

B2

zweite Laufbahn (Ausbuchtung, Schiebeverzahnungszahn)

AB

Abstand A_B > 0 von der Oberfläche des Rastelementes

AK

Abstand zur anliegenden Oberfläche des Rastelementes

1

Tragwelle

2

Schiebenocken

3

Rastvorrichtung

11

Schiebeverzahnung der Tragwelle

21

erste Nockenanordnung

22

zweite Nockenanordnung

23

Schaltkulisse

24

Öffnung

31

Rastaussparung

32

Feder

33

Rastelement, insbesondere Kugel

34

Öffnung

211

erster Nocken

212

zweiter Nocken

221

erster Nocken

222

zweiter Nocken

241

Schiebeverzahnung des Schiebennockens

311

Rastaussparungsboden

2411

erster Schiebeverzahnungszahn

2412

zweiter Schiebeverzahnungszahn

The following reference symbols are used in the figures:

L

Longitudinal axis of the supporting shaft

I - VII

first to seventh area (locking recess)

B1

first raceway (bulge, sliding spline tooth)

B2

second raceway (bulge, sliding gear tooth)

AWAY

Distance _AB > 0 from the surface of the locking element

AK

Distance to the adjacent surface of the locking element

1

supporting shaft

2

sliding cam

3

locking device

11

Sliding toothing of the support shaft

21

first cam arrangement

22

second cam arrangement

23

shift gate

24

opening

31

notch

32

Feather

33

Latching element, in particular ball

34

opening

211

first cam

212

second cam

221

first cam

222

second cam

241

Sliding toothing of the sliding cam

311

recess bottom

2411

first sliding gear tooth

2412

second sliding gear tooth

First, reference is made to FIG.

A sliding cam arrangement essentially comprises a support shaft 1 with at least one sliding cam 2. The sliding cam 2 is non-rotatably, but axially displaceably accommodated on the support shaft. For this purpose it can be provided, for example, that the sliding cam 2 has an opening 24 for receiving the support shaft 1, which is equipped with a sliding toothing 241 and the supporting shaft 1 is also equipped with a sliding toothing 11. The sliding cam 2 has a cam arrangement 21 with a first cam 211 and at least one second cam 212 . The cams 211 and 212 differ in terms of their cam contour, which can also be implemented in that the cams have different phase positions. Furthermore, the sliding cam 2 has a shift gate 23 . An actuator pin (not shown) can intervene here and carry out the corresponding desired axial displacement of the sliding cam 2 so that either the first cam 211 or the at least second cam 212 controls the associated gas exchange valve of an internal combustion engine (not shown). The way in which a sliding cam arrangement works and how it interacts with the gas exchange valves of an internal combustion engine is sufficiently known to a person skilled in the art, so that no detailed explanation is required here.

The sliding cam arrangement is also equipped with a latching device 3 which is set up to releasably fix the sliding cam 2 on the support shaft 1 in a first axial position and at least one second axial position. The latching device can comprise, for example, a latching recess 31 on the sliding cam side and a latching element/spring combination 32 and 33 on the supporting shaft side. The locking element can preferably be designed as a ball. Other shapes are also conceivable, such as a cylindrical roller. However, the following examples refer to a ball as the locking element.

Spring 32 and ball 33 are accommodated in a radially aligned opening 34 in the support shaft and press ball 33 against latching recess 31. Latching recess 31 is generally an axially aligned recess, in particular a circumferential recess, in the sliding cam or opening 24 of the sliding cam 2 and has a locking recess base 311 .

• - Erster Bereich I: abfallender Rastaussparungsboden
• - Zweiter Bereich II: ebener Rastaussparungsboden
• - Dritter Bereich III: ansteigender Rastaussparungsboden
• - Vierter Bereich IV: ebener Rastaussparungsboden
• - Fünfter Bereich V: abfallender Rastaussparungsboden
• - Sechster Bereich VI: ebener Rastaussparungsboden
• - Siebter Bereich VII: ansteigender Rastaussparungsboden.

The latching recess 31, in particular the latching recess base 311, can have, for example, seven areas in the axial direction. In a longitudinal section, these can be seen as locking contours. The latching contour has a wave-like shape in longitudinal section. In the axial direction, the following characteristics of the areas with the longitudinal axis L of the support shaft as a reference result:

• - First area I: sloping recess bottom
• - Second area II: level snap-in recess base
• - Third area III: rising snap-in recess floor
• - Fourth area IV: level snap-in recess floor
• - Fifth area V: sloping snap-in recess floor
• - Sixth area VI: level snap-in recess bottom
• - Seventh area VII: rising recess bottom.

In this context, sloping means that the base of the locking recess is moving away from the longitudinal axis of the support shaft. In this context, increasing means that the base of the locking recess turns toward the longitudinal axis of the support shaft. The flat areas can also be infinitesimally small, so to speak merely as a turning point between the adjacent rising or falling areas. The individual areas preferably merge seamlessly into one another.

In the radial direction, the fourth area protrudes further in the direction of the longitudinal axis L of the supporting shaft than the second area and the sixth area. The fourth area is, so to speak, an elevated area compared to the second area and the sixth area. Accordingly, when the sliding cam 2 is axially displaced, the ball 33 always slides over the fourth area, i.e. it is pressed in the direction of the support shaft 1 in order to choose between the first and third area or the fifth and seventh area. The sliding cam 2 is thus releasably fixed axially by the prestressing of the spring 32 or its exertion on the ball 33 . For more details, for example, on the DE 10 2017 219 287 A1 to get expelled.

According to the invention, it is provided that the latching recess 31, in particular the latching recess base 311, has at least in sections a first track B1 and at least a second track B2 for the locking element. The raceways B1, B2 preferably extend in the axial direction of the latching recess 31. The raceways B1, B2 are preferably arranged at a distance next to one another, as seen in the circumferential direction. In other words, another raceway is added to a raceway B1 for the latch member. A ball as a locking element 33 will therefore not roll on one track, but on at least two tracks B1 and B2, so that the resulting contact forces can be divided accordingly between two tracks B1, B2. The latching element 33 preferably touches the latching recess base 311 only on its tracks B1 or B2, so that the track can also be referred to as a contact track. Two tracks, in particular exactly two tracks, are preferably provided.

Examples of such configurations are in particular in the 11 until 13 pictured.

In particular, it is provided that the latching recess 31, in particular the latching recess base 311, has a distance A _K = 0 to the contacting surface of the latching element on the provided running surfaces B1, B2, with all other surfaces of the latching recess 31, in particular the latching recess base 311, being at a distance A _B > 0 have from the surface of the locking element.

The first track B1 and the at least second track B2 could for example be realized in that the recess 31, in particular the recess bottom 311, at least least in sections, is provided with two axially extending bulges, on which the locking element, in particular the ball 33, can roll in accordance with two raceways. The bulges then correspondingly form the raceways B1, B2 for the latching element.

In a preferred embodiment, the first raceway B1 and the at least second raceway B2 can be realized, for example, in that the first raceway B1 is realized by a first sliding toothing 2411 and the second raceway B2 by a second sliding toothing 2412 of the sliding toothing 241 that is present anyway. For this purpose, the latching recess 31, in particular the latching recess base 311, can be designed at least in sections as sliding teeth. The bulges are then correspondingly part of the sliding toothing or, in particular, two sliding toothing teeth form the two bulges and thus ultimately the two raceways B1 and B2. Such a design is particularly in the 13 good to see. The distances A _K and A _B are also shown here.

Provision can preferably be made for the bulge and/or the tooth of the sliding toothing to have a surface which is straight or concave in the circumferential direction, at least in sections.

The first track B1 and the at least second track B2 could also be realized, for example, by the locking recess 31, in particular the locking recess base 311, having a concave shape, in particular in the circumferential direction. Such a design is particularly in the 11 and 12 good to see. The distances A _K and A _B are also shown here.

In principle, the aforementioned configurations can also be combined, ie, for example, a concave or straight bottom of the locking recess with axially running bulges.

In principle, provision can be made for the first track B1 and the at least second track B2 to extend over the entire length of the latching recess 31 , in particular the latching recess base 311 .

Provision can preferably be made for the first track B1 and the at least second track B2 to be provided only in the third to fifth region of the latching recess 31 , in particular the latching recess base 311 . In other words, only the area which presses the locking element 33, in particular the ball, against the spring force in the direction of the longitudinal axis L of the support shaft 1 is equipped with the first track B1 and the at least second track B2. Taking into account the division of areas made above, these are areas III, IV and V, i.e. the elevation, so to speak, in particular the ramps and the plateau, which during the displacement process between the first axial position and the at least second axial position or vice versa by the locking body 33 , In particular the ball against the force of the spring 32 must be overcome.

Of course, features and details that are described in connection with a method also apply in connection with the device according to the invention and vice versa, so that with regard to the disclosure of the individual aspects of the invention reference is or can always be made to one another. In addition, an optionally described method according to the invention can be carried out with the device according to the invention.

QUOTES INCLUDED IN DESCRIPTION

This list of the documents cited by the applicant was 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.

Patent Literature Cited

• DE 102004011586 A1 [0002, 0003]
• DE 102011084043 A1 [0002, 0004]
• DE 102009005731 A1 [0002, 0005]
• DE 102017219287 A1 [0030]

Claims (14)

Sliding cam arrangement, comprising a supporting shaft (1) with a longitudinal axis (L) of the supporting shaft and at least one sliding cam (2) received on the supporting shaft (1) in a rotationally fixed and axially displaceable manner, wherein the sliding cam arrangement is equipped with a latching device (3) which is set up to releasably fix the sliding cam (2) in a first axial position and at least one second axial position, the latching device (3) comprising a latching recess (31) and a latching element-spring combination with a latching element (33), characterized in that the Latching recess (31), at least in sections, has a first track (B1) and at least one second track (B2) for the locking element (31). sliding cam arrangement claim 1 , characterized in that the locking element-spring combination comprises a spring (32) and a ball (33) as a locking element. Sliding cam arrangement according to at least one of the preceding claims, characterized in that the latching element (33) and the spring of the latching element-spring combination are accommodated in a radially aligned opening (34) in the support shaft (1). Sliding cam arrangement according to at least one of the preceding claims, characterized in that the latching recess (31) has a latching recess base (311). Sliding cam arrangement according to at least one of the preceding claims, characterized in that the latching recess (31), in particular the latching recess base (311), in the direction of the longitudinal axis (L) of the supporting shaft has a first region (I) with a sloping latching recess base, a second region (II) with a flat locking recess floor, a third area (III) with a rising locking recess floor, a fourth area (IV) with a flat locking recess floor, a fifth area (V) with a falling locking recess floor, a sixth area (VI) with a flat locking recess floor, and a seventh area (VII). has rising recess bottom. Sliding cam arrangement according to at least one of the preceding claims, characterized in that the fourth area is so small that the third area and fifth area merge into one another. Sliding cam arrangement according to at least one of the preceding claims, characterized in that the second area and/or sixth area is configured by radii arranged tangentially and merging into one another. Sliding cam arrangement according to at least one of the preceding claims, characterized in that the detent recess (31), in particular the detent recess base (311), on the provided running surfaces (B1, B2) has a distance A _K = 0 to the adjacent surface of the detent element, with all other Surfaces of the locking recess (31), in particular the locking recess base (311), have a distance A _B > 0 from the surface of the locking element. Sliding cam arrangement according to at least one of the preceding claims, characterized in that the latching recess (31), in particular the latching recess base (311), at least in sections, has a first bulge running in the axial direction forming the first track (B1) and a second bulge, the at least second Running track (B2) forming a bulge running in the axial direction. sliding cam arrangement claim 9 , characterized in that the sliding cam (2) has a sliding toothing (241), wherein the bulge forming the first track (B1) and running in the axial direction is formed by a first tooth (2411) of the sliding toothing and the second, the at least second raceway (B2) and running in the axial direction bulge is formed by a further tooth (2412) of the sliding toothing, in particular a further tooth arranged in the circumferential direction immediately next to the first tooth. sliding cam arrangement claim 9 or 10 characterized in that the bulge and/or the tooth (2411 or 2412) of the sliding toothing has, at least in sections, a straight or concave surface in the circumferential direction. Sliding cam arrangement according to at least one of the preceding claims, characterized in that the latching recess (31), in particular the latching recess base (311), is concave at least in sections. Sliding cam arrangement according to at least one of the preceding claims, characterized in that that area of the latching recess (31) which the latching element (33), in particular the ball, moves against the force of the spring (32) in the direction of the longitudinal axis (L) of the supporting shaft of the supporting shaft (1st ) presses, with the first career (B1) and at least the second track (B2). Sliding cam arrangement according to at least one of the preceding claims, characterized in that the locking recess (31) has two tracks (B1, B2).

Images