Sliding cam system and method for actuating the sliding cam system

Abstract

The invention relates to a sliding cam system, comprising a support shaft (3), a primary sliding cam (1), and at least one secondary sliding cam (2), wherein the sliding cams (1, 2) are received on the support shaft (3) so as to be axially displaceable but rotationally fixed, the sliding cam system is equipped with an electromagnetic actuator (4) for axially displacing the primary sliding cam (1), the sliding cam system is equipped with a push rod device (5) for axially displacing the at least one secondary sliding cam (2), and the push rod device (5) comprises a mechanical actuator (54). The invention further relates to a method for actuating a sliding cam system according to the invention, the axial displacement of the secondary sliding cam (2) being initiated by the mechanical actuator (54) of the push rod system (5).

Description

[0001] Sliding cam system, and methods for actuating the sliding cam system

[0002] The present invention relates to a sliding cam system according to the preamble of claim 1, and to a method for actuating the sliding cam system according to the invention according to claim 13.

[0003] A sliding cam system of the aforementioned type is known, for example, from WO 2020193560 Al. Here, a first sliding cam, also called a primary sliding cam, is actuated by an actuator, and further sliding cams, also called secondary sliding cams, are actuated by a push rod. The push rod can also be used as an adjusting element. The advantage lies in the fact that only one actuator is required to actuate several sliding cams. The other sliding cams are, in effect, remotely controlled by the push rod. This measure alone results in savings in material and installation space.

[0004] The sliding cam as such comprises, as is known, at least one cam assembly, wherein the cam assembly has a first and at least one second cam. The cams of the cam assembly differ with respect to their cam profile. Depending on the axial position of the sliding cam, either the first cam or the second cam can be selectively engaged with the associated gas exchange valve or cam follower.

[0005] The operation of the sliding cam system depends on the operating point of the combustion engine. Depending on the engine speed and load requirements, different cam profiles are engaged by the cam follower. This measure ultimately serves to optimize the gas exchange in the combustion engine and thus to reduce fuel consumption and / or optimize performance.

[0006] The range of possible switching cam profiles for the secondary sliding cam in an embodiment of the sliding cam system, as described, for example, in WO 2020193560 Al, is limited and restricted to V-shaped cam tracks. This is essentially due to the fact that the push rod has a pin for each secondary sliding cam to actuate the respective switching cam of the secondary sliding cam, which is radially immovable and thus always remains in the switching cam of the respective secondary sliding cam. Contact with the switching cam can therefore only occur in an axial direction, meaning that the respective secondary sliding cam can only be accelerated. Deceleration must therefore be achieved by locking the respective secondary sliding cam or by an additional axial stop between the secondary sliding cam and the cylinder head.This results, for example, in comparatively low shifting forces, low shifting speeds and / or suboptimal NVH behavior.

[0007] The present invention addresses this issue and aims to propose an improved sliding cam system, in particular a sliding cam system that eliminates, or at least mitigates, the disadvantages outlined above. Specifically, it seeks to overcome the limitations of the prior art regarding the switching kinematics and the possible cam tracks. In particular, the control of the secondary sliding cam is to be made more precise and variable, thereby achieving higher switching forces, higher switching speeds, and optimized NVH (noise, vibration, and harshness) behavior. Furthermore, the solution is intended to reduce the installation space, material costs, and complexity of electrical control components, thus improving overall system reliability.

[0008] According to the invention, this problem is solved by the pushrod assembly comprising a mechanical actuator for controlling the at least one secondary sliding cam. This design eliminates the need for a separate electromagnetic actuator for the secondary sliding cam. This results in savings in installation space, material, and manufacturing costs, as well as improved system reliability through the reduction of electrical control components. Furthermore, it becomes possible for the secondary sliding cam to control cam tracks other than exclusively V-shaped ones, such as S-shaped or Y-shaped cam tracks.The proposed invention can result in, in particular, improved switching behavior of the sliding cam system, such as higher achievable switching forces, higher switching speeds, and / or improved NVH behavior, through controlled deceleration of the secondary sliding cam at the end of the switching process. NVH (Noise, Vibration, Harshness) refers collectively to audible or perceptible vibrations in motor vehicles or machinery.

[0009] Further advantageous embodiments of the proposed invention arise in particular from the features of the dependent claims. The subject matter or features of the various claims can, in principle, be combined with one another in any way. In an advantageous embodiment of the present invention, the mechanical actuator may comprise a base body, a switching lever, a first actuator pin, and a second actuator pin. The integration of these components into the mechanical actuator enables precise and repeatable control of the switching movements of the secondary sliding cam. This results in reliable operation at higher switching speeds and an improvement in NVH (noise, vibration, and harshness) behavior.

[0010] In a further advantageous embodiment of the present invention, the switching lever may comprise a leg and two arms extending from the leg at its head, namely a first arm and a second arm, wherein the switching lever, in particular the leg, is rotatably connected to the push rod, the switching lever, in particular the leg, is slidably received in the base body, the arms each being equipped on their side facing the actuator pins with contact surfaces for actuating the actuator pins, wherein the switching lever, in particular the leg, is equipped at its end with a contact element which is in operative connection with a sliding cam of the at least one secondary sliding cam. This embodiment ensures an efficient transmission of the axial movement of the push rod to the actuator pins and thus a precise switching of the switching positions of the secondary sliding cam.In particular, a sliding cam system is proposed in which a mechanical actuator is actuated via a push rod such that a rotatably mounted lever is attached to the push rod. This lever, in interaction with a circumferential groove on the secondary sliding cam, is rotated such that, after the switching operation of the secondary sliding cam, the lever returns to its initial position. The positional changes of the push rod, lever, and secondary sliding cam thus result in uniquely identifiable combinations of positions that cause two switching pins, actuated by the lever, to engage in the corresponding cam track. This makes it possible, in particular, to actuate cam tracks other than V-shaped ones, such as S-shaped or Y-shaped cam tracks. Previously, only V-shaped cam tracks were conceivable for this application of the secondary sliding cam.

[0011] In a further advantageous embodiment of the present invention, the switching lever can be T-shaped, Y-shaped, star-shaped, or triangular. The variability of the switching lever's geometric design allows for flexible adaptation to different installation space and functional requirements, thereby making the sliding cam system more universally applicable. In a further advantageous embodiment of the present invention, the contact surfaces of the switching lever, particularly the arms, can be arranged at an angle or designed as curved contours. This design of the contact surfaces reduces friction between the switching lever and the actuator pins, thus minimizing wear. This increases the system's durability and operational reliability.

[0012] In a further advantageous embodiment of the present invention, the contact surfaces and / or the contact element of the switching lever can be hardened and / or coated. These measures increase resistance to mechanical wear and corrosion, which contributes to a longer service life and greater reliability of the system.

[0013] In a further advantageous embodiment of the present invention, the base body may comprise two cheeks, wherein the switching lever, in particular the leg of the switching lever, is received between the cheeks, wherein the switching lever, in particular the leg, is rotatably connected to the push rod by means of a pin connected to the push rod, the pin being received in elongated holes in the base body, in particular in the cheeks, for slidable support. The use of elongated holes in the cheeks of the base body allows precise guidance of the switching lever, thereby enabling its movement to be precisely controlled and optimizing the switching mechanism.

[0014] In a further advantageous embodiment of the present invention, the contact element can be configured as a pin-shaped section of the switching lever, in particular the leg, wherein the pin-shaped section engages in the sliding cam of the secondary sliding cam, which is configured as a circumferential groove. The direct mechanical coupling between the contact element and the sliding cam enables efficient and low-loss transmission of the movement, thereby increasing the reliability of the switching mechanism.

[0015] In a further advantageous embodiment of the present invention, the contact element can be designed as a fork-shaped element which is rotatably arranged on the switching lever, in particular on the leg, wherein the fork-shaped element engages the sliding cam of the secondary sliding cam, which is designed as a circumferential elevation. The fork-shaped design of the contact element improves the stability and precision of the motion coupling between the switching lever and the sliding cam.

[0016] In a further advantageous embodiment of the present invention, the secondary sliding cam can be equipped with a switching cam for engaging the actuator pins of the mechanical actuator, wherein the switching cam comprises a Y-shaped or two S-shaped cam tracks, and / or the primary sliding cam can be equipped with a switching cam for engaging the actuator pins of the electromagnetic actuator, wherein the switching cam comprises a Y-shaped rotating cam track or two S-shaped cam tracks. The use of Y- and S-shaped cam tracks enables more complex and application-optimized control of the cam movements, thereby allowing the motor performance to be better adapted to different operating conditions.

[0017] In a further advantageous embodiment of the present invention, the actuator pins can be provided with a releasable locking mechanism for the axial direction of movement in the base body, comprising in particular two circumferential and axially spaced grooves in each actuator pin, as well as a spring element that can be selectively brought into contact with the grooves. The locking mechanism of the actuator pins enables precise fixation in the desired position and prevents unintentional movements, thus increasing operational reliability.

[0018] In a further advantageous embodiment of the present invention, the mechanical actuator can be configured to change its switching position in a manner that is uniquely assignable to the position of the primary and secondary sliding cams, thus enabling coordinated actuation of the corresponding switching pins. The unique assignment of the switching position ensures precise synchronization of the cam profiles and thereby optimizes the efficiency of the gas exchange.

[0019] Furthermore, an advantageous method for actuating a sliding cam system according to the invention is to be proposed.

[0020] According to the invention, this problem is solved by a method according to claim 13.

[0021] By initiating the axial movement of the secondary sliding cam via a mechanical actuator of the pushrod system, the advantages of the mechanical actuator can be achieved for the pushrod system according to the invention. The mechanical control of the cam movement improves the robustness of the system and reduces its dependence on electrical components.

[0022] Further advantageous embodiments of the proposed invention arise in particular from the features of the dependent claims. The subject matter or features of the various claims can, in principle, be combined with one another in any way.

[0023] In an advantageous embodiment of the present invention, the method can be carried out using the process steps according to claim 14. These steps enable coordinated and low-loss control of the movements of primary and secondary sliding cams, thereby making the switching efficient and precise.

[0024] In a further advantageous embodiment of the present invention, it can be provided that the sliding cam system returns to the first switching state by means of a renewed axial displacement of the sliding cams by means of an inverse sequence of steps. This ensures a flexible and reliable return to the initial state, thereby extending the system functionality. Further features and advantages of the present invention will become clear with reference to the following description of preferred embodiments and the accompanying figures. The elements or features of the various embodiments can, in principle, be combined with one another as desired.

[0025] Fig. 1 shows a sliding cam system according to the invention in a perspective view;

[0026] Fig. 2 shows an exploded view of a mechanical actuator;

[0027] Fig. 3 - 11 shows a sliding cam system according to the invention in different versions;

[0028] Switching states;

[0029] Fig. 12 shows a further embodiment of a sliding cam system according to the invention, in particular the mechanical actuator;

[0030] Fig. 13 shows a further embodiment of the sliding cam system according to the invention, in particular the mechanical actuator.

[0031] The following reference symbols are used in the illustrations:

[0032] E end of the support shaft

[0033] L Longitudinal axis

[0034] 1 Primary sliding cam

[0035] 2 (first) secondary sliding cams

[0036] 3 Support shaft

[0037] 4 electromagnetic actuator

[0038] 5 pushrod device

[0039] 11 (first) cam arrangement

[0040] 12 second cam arrangement

[0041] 13 Gearshift mechanism

[0042] 14 Sliding cam, especially for the pin 51 (circumferential groove)

[0043] 21 (first) cam arrangement

[0044] 22 second cam arrangement

[0045] 23 Shift gate 24 Sliding gate, especially for the shift lever 544 (circumferential groove / circumferential raising)

[0046] 41 first actuator pin

[0047] 42 second actuator pin

[0048] 51 cones

[0049] 52 Push rod

[0050] 53 Pushrod mount

[0051] 54 mechanical actuator

[0052] 111 first cam

[0053] 112 second cam

[0054] 121 first cam

[0055] 122 second cam

[0056] 211 first cam

[0057] 212 second cam

[0058] 221 first cam

[0059] 222 second cam

[0060] 541 first actuator pin

[0061] 542 second actuator pin

[0062] 543 Basic body

[0063] 544 Shift lever

[0064] 545 Spring element / spring clip

[0065] 5411 Nut

[0066] 5421 Nut

[0067] 5431 first cheek

[0068] 5432 second cheek

[0069] 5433 Slot 5441 First arm

[0070] 5442 second arm

[0071] 5443 thighs

[0072] 5444 Pin (rotation axis of the switching lever)

[0073] 5445 Contact area

[0074] 5446 contact area

[0075] 5447 Contact element

[0076] 5447a Contact element (fork-shaped element)

[0077] 5448 bore

[0078] Features and details described in connection with a method naturally also apply to the device according to the invention, and vice versa, so that the disclosure regarding the individual aspects of the invention always makes or can make reciprocal reference. Furthermore, any described method according to the invention can be carried out with the device according to the invention.

[0079] The terminology used herein serves only to describe certain embodiments and is not intended to limit the disclosure. As used herein, the singular forms "a" and "the" are intended to include the plural forms unless the context otherwise makes clear. It will also be clear that the expressions "indicates" and / or "indicating," when used in this description, specify the presence of the aforementioned features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. As used herein, the expression "and / or" includes any and all combinations of one or more of the associated, listed elements.

[0080] First, particular reference is made to Fig. 1.

[0081] A sliding cam system essentially comprises a primary sliding cam 1, a secondary sliding cam 2, a support shaft 3, an electromagnetic actuator 4, and a pushrod assembly 5. The longitudinal axis L shown symbolizes the axial direction of the support shaft 3. The actuator 4 is an electromagnetically actuated actuator, i.e., the actuator pin(s) 41, 42 of the actuator 4 are electrically actuated via a magnetic coil.

[0082] The primary sliding cam 1 and the secondary sliding cam 2 are each mounted on the support shaft 3 in a rotationally fixed but axially displaceable manner. For this purpose, the sliding cams 1 and 2 are preferably mounted on the support shaft 3 by means of sliding teeth. Both sliding cams, in particular the primary sliding cam 1 and the secondary sliding cam 2, are preferably fixed axially in their switching positions by means of a spring-ball detent.

[0083] The primary sliding cam 1 has at least one cam arrangement 11, preferably a first cam arrangement 11 and a second cam arrangement 12. The figures also show a third and fourth cam arrangement per sliding cam. These may be present, but are irrelevant for a fundamental understanding of the invention.

[0084] The cam arrangement 11 or 12 comprises at least one first cam 111 and one second cam 112. The cams 111, 112 of the respective cam arrangement differ with respect to their cam contour, which can also be achieved by the cams having different phase positions.

[0085] The primary sliding cam 1 is further equipped with a switching cam 13. The electromagnetic actuator 4 is associated with the switching cam 13 of the primary sliding cam 1; that is, the electromagnetic actuator 4 comprises a first actuator pin 41 and a second actuator pin 42, which can engage in the switching cam 13 of the primary sliding cam 1 to displace the primary sliding cam 1 between a first axial position and a second axial position. The switching cam 13 can, for example, comprise two S-shaped circumferential cam tracks or one Y-shaped circumferential cam track. The cam track is typically designed as a groove.

[0086] The switching, i.e. axial displacement, of a sliding cam on the support shaft 3 of a sliding cam shaft by means of an actuator 4 is sufficiently known to the person skilled in the art.

[0087] The secondary sliding cam 2 has at least one cam arrangement 21, preferably a first cam arrangement 21 and a second cam arrangement 22. The cam arrangement 21 or 22 comprises at least a first cam 211 and a second cam 212. The cams 211, 212 of the respective cam arrangement differ with respect to their cam contour, which can also be achieved by the cams having different phase positions. It is also possible to switch between a cam contour and a so-called cylindrical zero-lift cam for cylinder deactivation.

[0088] The sliding cam system is further equipped with the push rod assembly 5 mentioned above. The push rod assembly 5 is designed to axially displace the secondary sliding cam 2 on the support shaft 3 in relation to the primary sliding cam 1. For this purpose, the push rod assembly 5 comprises a push rod 52, which is coupled to the primary sliding cam 1 such that an axial displacement of the primary sliding cam 1 results in an axial displacement of the push rod and thus of the secondary sliding cam 2. It is possible that the displacement of the secondary sliding cam 2 occurs with a time delay relative to that of the primary sliding cam 1. To couple the push rod 52 to the primary sliding cam 1, the primary sliding cam 1 is equipped with a sliding cam 14 in the form of a circumferential groove into which a pin 51 of the push rod 52 engages.It is generally intended that the axial displacement of the push rod 52 corresponds to the axial displacement of the primary sliding cam 1.

[0089] The pushrod assembly 5 further comprises a pushrod receptacle 53 in which the pushrod 52 can be axially displaced. The pushrod receptacle 53 can, for example, be part of bearing mounts for the support shaft 3, or be mounted as a separate component in the cylinder head. The bearing mounts, in turn, can be attached to a cylinder head, cylinder cover, cylinder hood, or hood module (not shown). Essentially, the pushrod receptacle 53 is fixed in position. The pushrod 52 is aligned parallel to the support shaft 3 or its longitudinal axis L, or can be displaced parallel to the support shaft 3 or its longitudinal axis L.

[0090] According to the invention, the push rod assembly 5 is equipped with a mechanical actuator 54, which can be mechanically actuated by the push rod 52. In other words, a second electromagnetically actuated actuator for the secondary push cam 2 is not required for the sliding cam system, thus saving costs, weight, and installation space. Likewise, the use of alternative cam tracks for the switching cam 23 of the secondary push cam 2 is enabled, for example, Y- and S-shaped cam tracks. The essential differences between the mechanical actuator 54 and the electromagnetic actuator 4 should be highlighted again here. The electromagnetically actuated actuator requires a power supply to operate. The timing of the pin actuation is directly determined by, for example, a control unit.In contrast, the mechanically actuated actuator does not require a power supply. The timing of its actuation is determined by the preceding movement of the primary sliding cam and the push rod, resulting in a more mechanically coupled process.

[0091] The following refers to Fig. 2 and 13:

[0092] The mechanical actuator 54 essentially comprises a base body 543, a switching lever 544, as well as a first actuator pin 541 and a second actuator pin 542.

[0093] The base body 543 is attached to a fixed position, for example connected to the cylinder head, the cylinder cover or another component of the internal combustion engine.

[0094] The actuator pins 541, 542 are slidably and, in particular, rotatably mounted in the base body 543. The direction of displacement of the actuator pins 541, 542 is radially aligned with the longitudinal axis L of the support shaft 3. Furthermore, the actuator pins 541, 542 can be detachably locked in two displacement positions by means of a locking device. For this purpose, the actuator pins 541, 542 each have, for example, two circumferential grooves 5411, 5421 into which a spring element 545 can engage. The actuator pins 541, 542 can each engage in a switching cam 23 of the secondary sliding cam 2 for axial displacement of the secondary sliding cam 2.

[0095] The switching cam 23 of the secondary sliding cam element 2 for the engagement of the actuator pins 541, 542 of the mechanical actuator 54 can comprise two S-shaped cam tracks or one Y-shaped cam track. Previously, only V-shaped cam tracks were possible in comparable sliding cam systems without a mechanical actuator.

[0096] The switching lever 544 preferably has a T-shaped form, comprising a leg 5443 and two arms 5441, 5442 projecting from the head of the leg 5443. The first arm 5441 projects over the first actuator pin 541, and the second arm 5442 projects over the second actuator pin 542. The basic design of the switching lever 544 can vary depending on the available installation space or the ratio of the primary sliding cam's displacement to the secondary sliding cam's pin stroke, allowing for deviations from the T-shaped configuration. For example, the switching lever can be T-shaped, Y-shaped, star-shaped, or triangular. In the sense of the inventive idea, the switching lever 544 is understood in particular to be a component of the mechanical actuator 54 which can be in operative connection with the actuator pins 541, 542 of the mechanical actuator 54.

[0097] The switching lever 544 is connected to the push rod 52 via a rotary bearing. The rotary bearing can, for example, comprise a push rod-side pin 5444 and a bore in the switching lever 544, in particular the leg 5443 of the switching lever 544. The switching lever 544 is thus rotatably mounted on the push rod 52.

[0098] It can further be provided that the base body 543 comprises two opposing cheeks 5431, 5432, with the leg 5443 being received between the two cheeks 5431, 5432. In this context, it can be provided that the cheeks 5431 are each equipped with an elongated hole 5433, with the pin 5444 being slidably received in the elongated holes 5433. The elongated hole(s) 5433 are preferably aligned axially, in particular parallel, to the longitudinal axis L. The elongated holes form, in a sense, an axial guide for the pin 5444 and thus for the switching lever 544. The push rod 52 can encircle the base body 543 so that the pin 5444 completely penetrates the base body 543.

[0099] The push rod 52 with the pin 5444 can also be mounted between the cheeks 5431, thus eliminating the need for the elongated hole in the cheeks. The switching lever 544 is slidably mounted in the base body 543. Such an embodiment is shown in Figure 12.

[0100] The axis of rotation, and thus ultimately the orientation of the pin 5444, is perpendicular to the direction of movement of the push rod 52, or in other words, perpendicular to the longitudinal axis L of the support shaft 3. The direction of movement of the switching lever 544 is parallel to the direction of movement of the push rod 52, or in other words, parallel to the longitudinal axis L of the support shaft 3. The interaction of the elongated hole 5433 and the pin 5444 results in a type of rotary-sliding bearing. The switching lever 544 is further equipped at the free end of the leg 5443 with a contact element 5447. The contact element 5447 is an element that is in contact with a sliding cam 24 of the secondary sliding cam 2, which is designed as a circumferential groove. The contact element 5447 can be designed simply as a pin-shaped end of the leg 5443.

[0101] However, other forms are also conceivable, such as a fork-shaped design of the contact element 5447. For example, the sliding cam can be designed as a circumferential ridge or central web that is encompassed by the fork-shaped contact element 5447. The fork-shaped contact element 5447 can be operatively connected to the leg 5443 of the switching lever 544 via a pivot joint. Such a design is shown in Figure 13.

[0102] The arms 5441, 5442 of the switching lever 544 each have a contact surface 5445, 5446 on their side facing the actuator pins 541, 542. This results in a contact surface 5445 facing the first actuator pin 541 and a contact surface 5446 facing the second actuator pin 542. Essentially, the leg 5443 is arranged between the two actuator pins 541, 542 of the mechanical actuator 54.

[0103] The free end of leg 5443 is preferably in permanent operative connection with the sliding cam 24 of the secondary sliding cam 2, which is designed as a circumferential groove. The free ends of arms 5441, 5442 are preferably alternately in operative connection with the respective associated actuator pins 541, 542.

[0104] Further details of the sliding cam system according to the invention will become apparent in particular from the description of a switching process of the sliding cam system. Reference is made in particular to Figures 3 to 11.

[0105] It is understood that only a few selected process steps are presented here, as they are helpful for understanding the process according to the invention. The process may include further steps or intermediate steps known to those skilled in the art.

[0106] The respective switching states in Fig. 3, Fig. 11, and Fig. 7 are characterized by the fact that either the first cams 111, 121, 211, 221 or the second cams 112, 122, 212, 222 of the respective sliding cams 1, 2 can come into contact with the associated valves (not shown). For this purpose, the sliding cams 1, 2 are axially displaced accordingly on the support shaft 3.

[0107] Figures 3 to 7 illustrate the transition from a first switching state to a second switching state. Figures 7 to 11 illustrate the transition from a second switching state back to a first switching state. Figures 4 to 6 and 8 to 10 each depict intermediate states.

[0108] For clarity, the states shown in Figures 3 to 11 are designated as the first to ninth states. In the following considerations, it is assumed that the support shaft 3 rotates and that the respective switching cams 13, 23 are traversed by the respective actuator pins 41, 42, 541, 542.

[0109] When referring to retracted actuator pins, this means actuator pins that are retracted within the respective actuator. Conversely, actuator pins described in this way are not in contact with the associated mechanism.

[0110] When extended actuator pins are described, this refers to actuator pins that have been extended from the respective actuator. Conversely, actuator pins described in this way are in contact with the associated backdrop.

[0111] Figure 3 shows the sliding cam system in a first state, in which the second cams 112, 122 and 212, 222 of the respective cam arrangement 11, 12, 21, 22 interact with the associated valves (valves not shown here). The first state can also be referred to as the first switching state.

[0112] The primary sliding cam 1 is in a first axial position and the secondary sliding cam 2 is also in a first axial position.

[0113] The actuator pins 41, 42 of the electromagnetic actuator 4 are retracted, i.e., not in contact with the associated switching cam 13.

[0114] The push rod 52 or the pin 51 is located in a first position near the end of the support shaft designated by reference numeral E. The support shaft end E is used here as a fixed position to illustrate a change in the position of the relevant elements of the sliding cam system according to the invention. For illustrative purposes, and particularly for geometric orientation, it can be provided that this is the end E that is closer to the electromagnetic actuator 4. Furthermore, it is also provided that the base body 543 is mounted in a fixed position. Preferably, the base body 543 is connected to the cylinder head, cylinder cover or cylinder hood, or hood module (not shown).

[0115] The switching lever 544 is in a first, vertical rotational and sliding position, characterized by a vertically oriented leg 5443 and a correspondingly horizontal orientation of the arms 5441, 5442. It is further characterized by the proximity of leg 5443 to the second actuator pin 542 of the mechanical actuator 54. The actuator pins 541, 542 are used here as fixed positions to illustrate a change in the sliding position of the switching lever 544. It is also evident that the second actuator pin 542 is closer to the end E of the support shaft 3 selected here than the first actuator pin 541.

[0116] The actuator pins 541, 542 of the mechanical actuator 54 are retracted.

[0117] Figure 4 shows the sliding cam system in a second state. This state can also be described as an intermediate state, in which the sliding cams 1, 2, and in particular initially the primary sliding cam 1, are on their way from the first switching state to a second switching state.

[0118] The second actuator pin 42 of the electromagnetic actuator 4 is extended, i.e., retracted into the switching cam 13 of the primary sliding cam 1. The retraction of the second actuator pin 42 into the switching cam 13, through interaction with the switching groove, causes an axial displacement of the primary sliding cam 1 away from end E. This movement is initiated here.

[0119] By engaging the pin 51 of the push rod 52 in the sliding cam 14, the push rod 52 is moved with the primary sliding cam. The push rod 52 is preferably moved simultaneously with the primary sliding cam 1. A special design of the mechanical actuator allows the secondary sliding cam to be moved with a time delay relative to the primary sliding cam. In Fig. 5, the sliding cam system is shown in a third state. This state can also be described as a further intermediate state in which the secondary sliding cam 2 is on its way from the first switching state to a second switching state.

[0120] The primary sliding cam 1 is in a second axial position far from the end E and the secondary sliding cam 2 is still in the first axial position near the end E .

[0121] The push rod 52 or the pin 51 of the push rod is in a second position, away from the end E.

[0122] Since the position of the push rod 52, and thus also the position of the switching lever 544, in particular the axis of rotation 5444 of the leg 5443, has changed with respect to the secondary sliding cam 2, and the contact element 5447 is engaged with the associated groove 24 of the secondary sliding cam 2, the position of the switching lever 544 also changes. The switching lever 544 is in a right-tilted rotational and sliding position, characterized by a leg 5443 tilted in one direction away from the end E and a correspondingly tilted orientation of the arms 5441, 5442. It is further characterized by the proximity of the leg 5443 to the first actuator pin 541 of the mechanical actuator 54.

[0123] It is evident that the contact surface 5445 of the first arm 5441 has come into contact with the first actuator pin 541, such that the first actuator pin 541 has retracted into the associated switching cam 23 of the secondary sliding cam 2. With the extension of the first actuator pin 541 of the mechanical actuator 54, i.e., its retraction into the switching cam 23, the axial displacement of the secondary sliding cam 2 is initiated. The secondary sliding cam 2 is displaced from its first axial position, near end E, to a second axial position, farther from end E.

[0124] Figure 6 shows the sliding cam system in a fourth state. This state can also be described as a further intermediate state, in which the secondary sliding cam 2 is in its second switching state, but the first actuator pin 541 has not yet been moved back into the base body 543. The primary sliding cam 1 is in its second axial position, furthest from end E, and the secondary sliding cam 2 is also in its second axial position, furthest from end E.

[0125] The second actuator pin 42 of the electromagnetic actuator 4 is extended from the switching cam 13 of the primary sliding cam 1.

[0126] The push rod 52 or the pin 51 is in a second position, far from the end E .

[0127] The switching lever 544 is again in the vertical rotation and sliding position, characterized by a vertically aligned leg 5443 and a correspondingly horizontal alignment of the arms 5441, 5442. It is also characterized by the distance of the leg 5443 to the second actuator pin 542 of the mechanical actuator 54.

[0128] The first actuator pin 541 of the mechanical actuator 54 is still in the associated switching cam 23 of the secondary sliding cam 2, but is about to be pushed back into the base body 543 of the mechanical actuator 54 through the radial groove contour of the switching cam 23.

[0129] Figure 7 shows the sliding cam system in a fifth state, in which the first cams 111, 121 and 211, 221 of the cam arrangement 11, 12, 21, 22 interact with the associated valves (valves not shown here). The fifth state can also be referred to as the second switching state.

[0130] The primary sliding cam 1 is in the second axial position and the secondary sliding cam 2 is also in the second axial position.

[0131] The actuator pins 41, 42 of the electromagnetic actuator 4 are retracted.

[0132] The push rod 52 or the pin 51 is in the second position, far from the end E.

[0133] The switching lever 544 is in a second vertical rotary and sliding position, characterized by a vertically aligned leg 5443 and a correspondingly horizontal alignment of the arms 5441, 5442. It is also characterized by the distance of the leg 5443 to the second actuator pin 542 of the mechanical actuator 54. The actuator pins 541, 542 of the mechanical actuator 54 are retracted, i.e., not in contact with the associated switching cam 23.

[0134] Figure 8 shows the sliding cam system in a sixth state. This state can also be described as a further intermediate state in which the sliding cams 1, 2, and in particular initially the primary sliding cam 1, are on their way from the second switching state to the first switching state. The return movement is essentially the reverse of the process already outlined above.

[0135] The first actuator pin 41 of the electromagnetic actuator 4 is extended, i.e., retracted into the switching cam 13 of the primary sliding cam 1. The retraction of the first actuator pin 41 into the switching cam 13 accordingly causes an axial displacement of the primary sliding cam 1 towards end E.

[0136] The secondary sliding cam 2 is still in the second axial position far from the end E.

[0137] The push rod 52 or the pin 51 is still in the second position, away from the end E.

[0138] The actuator pins 541, 542 of the mechanical actuator 54 are both still retracted, i.e. not in contact with the associated switching cam 23 of the secondary sliding element.

[0139] Figure 9 shows the sliding cam system in a seventh state. This state can also be described as a further intermediate state, in which the primary sliding cam 1 is again in its first axial position or in its first switching state.

[0140] Since the position of the push rod 52, and thus also the position of the pivot axis 5444 of the leg 5443, has changed with respect to the secondary sliding cam 2, and the contact element 5447 is engaged with the associated sliding cam 24 of the secondary sliding cam 2, the position of the switching lever 544 also changes. The switching lever 544 is in a left-tilted rotational and sliding position, characterized by a leg 5443 tilted to the left and a correspondingly tilted orientation of the arms 5441, 5442. It is also characterized by the distance of the leg 5443 from the first actuator pin 541 of the mechanical actuator 54.

[0141] It can be seen that the contact surface 5446 of the second arm 5442 has come into contact with the second actuator pin 542, such that the second actuator pin 542 has been extended, i.e., has come into contact with the associated switching cam 23 of the secondary sliding cam 2.

[0142] The extension of the second actuator pin 542 of the mechanical actuator 54 initiates the axial displacement of the secondary sliding cam 2. The secondary sliding cam 2 is moved from its second axial position, far from end E, to the first axial position of the secondary sliding cam 2, near end E.

[0143] Figure 10 shows the sliding cam system in an eighth state. This state can also be described as a further intermediate state, in which the sliding cams 1, 2 are on their way from the second switching state to the first switching state, or have already arrived there.

[0144] The primary sliding cam 1 is located in the first axial position near the end E and the secondary sliding cam 2 is also located in the first axial position near the end E.

[0145] Both actuator pins 41, 42 of the electromagnetic actuator 4 are extended from the switching cam 13 of the primary sliding cam 1, i.e. retracted into the electromagnetic actuator 4.

[0146] The push rod 52 or the pin 51 remains in the first position, towards the end E.

[0147] The switching lever 544 is again in the first vertical rotational and sliding position, characterized by a vertically aligned leg 5443 and a correspondingly horizontal alignment of the arms 5441, 5442. It is also characterized by the distance of the leg 5443 from the first actuator pin 541 of the mechanical actuator 54. The second actuator pin 542 of the mechanical actuator 54 is still in the associated switching cam 23 of the secondary sliding cam 2, but is about to be pushed back into the base body 543 of the mechanical actuator 54 by the contour of the switching cam 23.

[0148] In Fig. 11 the sliding cam system is shown again in its first state, in which the second cams 112, 122 and 212, 222 of the respective cam arrangement 11, 12, 21, 22 interact with the associated valves (valves not shown here).

[0149] The primary sliding cam 1 is in a first axial position and the secondary sliding cam 2 is also in a first axial position.

[0150] The actuator pins 41, 42 of the electromagnetic actuator 4 are retracted.

[0151] The push rod 52 or the pin 51 is in a first position, near the end E.

[0152] The switching lever 544 is in the first vertical rotation and sliding position, characterized by a vertically aligned leg 5443 and a correspondingly horizontal alignment of the arms 5441, 5442. It is also characterized by a distance of the leg 5443 to the first actuator pin 541 of the mechanical actuator 54.

[0153] The actuator pins 541, 542 of the mechanical actuator 54 are retracted.

[0154] In principle, the invention is not limited to the embodiments outlined above. Rather, variations are conceivable without deviating from the inventive idea, particularly with regard to the number of secondary sliding cams 2. For example, one or more secondary sliding cams 2 can be provided, each of which can be moved by a further mechanical actuator 54 (not shown). It is also conceivable, of course, that the cam arrangements each have more than two cams.

Claims

22 Claims 1. Sliding cam system, comprising - a support shaft (3) - a primary sliding cam (1) - at least one secondary sliding cam (2) wherein - the sliding cams (1, 2) are axially displaceable, but rotationally fixed on the support shaft (3), wherein - the sliding cam system is equipped with an electromagnetic actuator (4) for axial displacement of the primary sliding cam (1), wherein - the sliding cam system is equipped with a push rod device (5) for axial displacement of the at least one secondary sliding cam (2), characterized by the fact that the push rod assembly (5) comprises a mechanical actuator (54).

2. Sliding cam system according to claim 1, characterized in that the mechanical actuator (54) comprises a base body (543), a switching lever (544), a first actuator pin (541) and a second actuator pin (542).

3. Sliding cam system according to at least one of the preceding claims, characterized in that - the switching lever (544) comprises a leg (5443) and two arms extending towards the head side of the leg (5443), namely a first arm (5441) and a second arm (5442), wherein - the switching lever (544), in particular the leg (5443), is rotatably connected to the push rod (52), - the switching lever (544), in particular the leg (5443), is slidably received in the base body (543), wherein - the arms (5441, 5442) are each equipped on their side facing the actuator pins (541, 542) with contact surfaces (5445, 5446) for actuating the actuator pins (541, 542), wherein - the switching lever (544), in particular the leg (5443), is equipped at its end with a contact element (5447) which is in operative connection with a displacement cam (24) of the at least one secondary sliding cam (2).

4. Sliding cam system according to at least one of the preceding claims, characterized in that the switching lever (544) is T-shaped, Y-shaped, star-shaped or triangular in shape.

5. Sliding cam system according to at least one of the preceding claims, characterized in that the contact surfaces (5445, 5446) are arranged obliquely or are designed as curved contours.

6. Sliding cam system according to at least one of the preceding claims, characterized in that the contact surfaces (5445, 5446) and / or the contact element (5447) is hardened and / or coated.

7. Sliding cam system according to at least one of the preceding claims, characterized in that the base body (543) comprises two cheeks (5431, 5432), wherein the switching lever (544), in particular the leg (5443) of the switching lever (544), is received between the cheeks (5431, 5432), wherein - the switching lever (544), in particular the leg (5443), is rotatably connected to the push rod (52) by means of a pin (5444) connected to the push rod (52), wherein - the pin (5444) is received in elongated holes (5433) of the base body (543), in particular the cheeks (5431, 5432), for slidable mounting.

8. Sliding cam system according to at least one of the preceding claims, characterized in that the contact element (5447) is designed as a pin-shaped section of the switching lever, in particular of the leg (5443), wherein the pin-shaped section engages in the sliding cam (24) of the secondary sliding cam element designed as a circumferential groove.

9. Sliding cam system according to at least one of the preceding claims, characterized in that the contact element (5447) is designed as a fork-shaped element which is rotatably arranged on the switching lever (544), in particular the leg (5443), wherein the fork-shaped element engages the sliding cam (24) of the secondary sliding cam element which is designed as a circumferential elevation.

10. Sliding cam system according to at least one of the preceding claims, characterized in that the secondary sliding cam (2) is equipped with a switching cam (23) for engagement of the actuator pins (541, 542) of the mechanical actuator (54), wherein the switching cam (23) comprises a Y-shaped or two S-shaped cam tracks, and / or that the primary sliding cam (1) is equipped with a switching cam (13) for engagement of the actuator pins (41, 42) of the electromagnetic actuator (4), wherein the switching cam (13) comprises a Y-shaped circumferential cam track or two S-shaped cam tracks.

11. Sliding cam system according to at least one of the preceding claims, characterized in that the actuator pins (541, 542) of the mechanical actuator (54) are received in the base body (543) with a releasable locking mechanism for the axial direction of movement, comprising in particular two circumferential and axially spaced grooves (5411, 5421) in the actuator pins, and a spring element (545) that can be selectively brought into contact with the grooves.

12. Sliding cam system according to at least one of the preceding claims, characterized in that the mechanical actuator is configured to change its switching position in a way that is uniquely assignable depending on the position of the primary and secondary cams, thus enabling coordinated control of associated switching pins.

13. Method for actuating a sliding cam system according to at least one of the preceding claims, characterized in that the axial displacement of the secondary sliding cam (2) is initiated by the mechanical actuator (54) of the push rod system (5).

14. Method according to claim 13 with a sliding cam system according to at least claims 2 and 3, characterized by the following steps: a) Provision of an initial switching state in which: - The primary sliding cam (1) and the secondary sliding cam (2) are located in a first axial position on the support shaft (3), the support shaft (3) having an end (E); - The actuator pins (41, 42) of the electromagnetic actuator (4) are retracted; - The push rod (52) is in a first position near the end (E); - The switching lever (544) is arranged in a first vertical rotation and sliding position, characterized by a vertically oriented leg (5443)25 and horizontally aligned arms (5441, 5442), wherein the leg (5443) is positioned near the second actuator pin (542) of the mechanical actuator (54); - The actuator pins (541, 542) of the mechanical actuator (54) are retracted; b) Displacement of the primary sliding cam (1) into a second axial position by extending the second actuator pin (42) from the electromagnetic actuator (4) and retracting it into the switching cam (13) of the primary sliding cam (1), thereby causing an axial movement of the primary sliding cam (1) from the first position near one end (E) of the support shaft 3 to a second position far from the end (E); c) Displacement of the push rod (52) into a second position far from the end (E) depending on the axial displacement of the primary sliding cam (1), wherein the switching lever (544) of the mechanical actuator (54) is moved into a second position far from the second actuator pin (542) of the mechanical actuator (54) towards the first actuator pin (541), whereby the switching lever (544) enters a tilted rotary position, characterized by an orientation of the leg (5443) in the direction away from the end (E), wherein the switching lever (544) actuates the first actuator pin (541) of the mechanical actuator (54) to engage in the switching cam (23) of the secondary sliding cam element (2) in order to move the secondary sliding cam (2) from the first axial position to a second axial position. d) Reaching a second switching state in which: - The primary sliding cam (1) and the secondary sliding cam (2) are in the second axial position; - The actuator pins (41, 42) of the electromagnetic actuator (4) have retracted, - The push rod (52) is in the second position furthest from the end (E); - The switching lever (544) is arranged in a second vertical rotation and displacement position, characterized by a vertically aligned leg (5443) and horizontally aligned arms (5441, 5442), wherein the leg (5443) is positioned far from the second actuator pin (542) and near the first actuator pin (541) of the mechanical actuator (54); The actuator pins (541, 542) of the mechanical actuator (54) are retracted.26 15. Method according to claim 14, characterized in that the sliding cam system returns to the first switching state by means of a renewed axial displacement of the sliding cams (1, 2) by means of an inverse sequence of steps a) to d).

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