Coupling device, valve system and method for assembling a coupling device or a valve system

Abstract

A coupling device (1) for connecting a drive shaft (31) of an actuator (3) to a driven shaft (51) of an exhaust valve (5). The coupling device (1) defines a rotational axis (A) and comprises a torsionally rigid retainer (2) having an axially extending slot (25), a coupling rod (45) received in the slot (25) for translational movement relative to the retainer (2) in the direction of the rotational axis (A), and an elastic element (4) biasing the coupling rod (45) in the direction of the rotational axis (A) and having an attachment section (42) fixed to the retainer (2); wherein the retainer (2) and the coupling rod (45) are non-rotatably connected.

Description

Technical Field

[0001] This invention relates to a coupling device for connecting the drive shaft of an actuator to the driven shaft of an exhaust valve. The invention also relates to a valve system comprising an actuator having a drive shaft, an exhaust valve having a driven shaft, and a coupling device. The invention further relates to a method for assembling the coupling device and a method for assembling a valve system. Background Technology

[0002] Exhaust line valves are typically equipped with coupling devices to connect them to actuators for their operation. Although the driven shaft of an exhaust valve can theoretically be directly coupled to the drive shaft of an actuator (such as an electric motor), a coupling device is usually used as an intermediate component connecting the driven and drive shafts. The coupling device serves the general task of compensating for tolerances caused by manufacturing errors or thermal expansion. Manufacturing errors can cause misalignment between the drive shaft of the valve actuator and the driven shaft of the exhaust valve in one or more of the axial, radial, and / or angular directions. Furthermore, because exhaust valve components are typically subjected to temperatures of several 100°C, while valve actuators require ambient temperatures well below 100°C to operate correctly for extended periods, the driven shaft experiences significant thermal stress due to the temperature gradient.

[0003] Exhaust systems designed to enhance performance characteristics often include exhaust valves to improve sound emission characteristics and engine power characteristics. Most systems include only two settings: a closed or fully open valve disc. In many cases, a closed valve results in a quieter sound, while an open valve leads to increased volume. Many car enthusiasts prefer a louder sound. However, exhaust valve systems are required to comply with increasingly stringent certification regulations. To optimize performance while ensuring compliance, an exhaust valve system that can precisely control both desired noise emissions and engine performance standards is needed.

[0004] US 10,060,360B2 recommends the use of a coupling device including an elastic member that is axially compressed between driven members, wherein the elastic member causes the driven members to rotate by means of a torsion spring. The drive member and driven members are exclusively connected via the elastic member, which is axially and circumferentially expandable and contractable. When a torque exceeding the resistance of the elastic member is applied from the drive member toward the driven member, the drive tab of the drive member can directly engage a first edge or a second edge of the driven member. Therefore, the drive member, and the corresponding drive shaft and driven shaft respectively attached to it, are rotatable relative to each other by an angular clearance between the drive tab and the opposing end portions of the raised edges. This clearance prevents the valve member or flap from being precisely positioned in a specific desired location during operation. Furthermore, whenever the direction of movement of the drive shaft reverses, an unavoidable impact sound is generated, resulting in a hissing noise.

[0005] In EP 2180167 B1, a coupling device is proposed that includes an elastic spring directly coupling the drive shaft to the driven shaft. However, it has shown unreliable operation, especially under high thermal loads, because the structural integrity of the spring is compromised, making valve positioning unreliable. Overheating can even cause the torsion spring to fail due to thermal stress exceeding the permissible axial load. Furthermore, since the valves using the proposed coupling device are designed to bias the valve disc against the valve seat in its closed position, the valve disc may be damaged during repeated use due to circumferential biasing forces acting on the valve disc in addition to the closing force and thermal stress.

[0006] Especially in performance exhaust systems that experience rapid pulses of exhaust gas leaving the cylinders of a performance internal combustion engine, the pulse impacts the valve components, causing them to start making a clicking sound due to the elasticity of the springs connecting the drive shaft and the driven shaft, or in the worst case, even resonate with the exhaust pulses.

[0007] Another valve coupling device is proposed in DE 102019120959 A1. This coupling device is proposed as a bushing cooperating with a helical spring, which has a straight section at the opposite end of the spring. The straight spring section engages a corresponding recess in the bushing, thereby allowing rotational and translational degrees of freedom of the spring relative to the bushing. DE 102019120959 A1 attempts to avoid rattling noise when the direction of movement of the valve disc is changed by a bias spring; however, rattling noise still occurs during rapid changes in movement or position. The valve actuation design in DE 102019120959 A1 is quite large and too large for some exhaust system design configurations. Due to its bulk, the valve coupling device may cause premature failure of the valve actuation due to the large mass of the valve coupling device, and because too much heat is transferred from the valve disc to the actuator during prolonged operation. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of the prior art and, in particular, to provide a valve system and a coupling device that have improved reliability, especially in terms of space requirements, heat load resistance, improved positioning, and reduced unwanted noise impact.

[0009] This objective is addressed by the subject matter of the independent claims.

[0010] Therefore, a coupling device is provided for connecting the drive shaft of an actuator to the driven shaft of an exhaust valve. The actuator may, in particular, include an electric motor, such as a stepper motor, servo motor, brushed DC motor, electrically excited DC motor, permanent magnet DC motor, brushless DC motor, switched reluctance motor, torque motor, synchronous motor, etc. Preferably, the actuator is a servo motor or a stepper motor. The driven shaft of the actuator transmits movement from the actuator toward the driven component including the exhaust valve. The drive shaft is preferably directly coupled to the electromagnetic component of the electric motor, or coupled to the electromagnetic component of the electric motor via a reduction gear transmission.

[0011] An exhaust valve includes a valve member, such as a flap, attached to a driven shaft. The driven shaft is configured to receive rotational motion and / or torque from a drive shaft of an actuator to transmit torque and / or rotational motion toward the valve member. Preferably, the valve member (particularly the flap) and the driven shaft are non-rotatably connected to each other; in other words, the driven shaft and the valve member are connected in a torque-resistant manner. For example, the valve member may be welded to the driven shaft, or the valve member and the driven shaft may be forged as a single unit. The valve member of the exhaust valve is specifically configured to be movable within a preferred tubular section of an exhaust passage for selectively opening or closing the section of the exhaust passage to transmit exhaust and / or sound. Specifically, the exhaust valve may include a tubular section of an exhaust system in which the flap is arranged, wherein the size of the flap is determined such that the flap can close as a cube. The shape of the flap may correspond to the shape of the internal cross-section of the tubular section. The driven shaft is preferably arranged perpendicular to the orientation of the tubular section. The driven shaft may be guided into the tubular section through an opening provided with a seal. The driven shaft defines the axis of the shaft about which the valve component can rotate. The drive shaft defines the drive axis. In a preferred embodiment of the valve system, the drive axis and the valve axis are aligned coaxially. Alternatively, the valve axis may be offset relative to the drive axis, specifically angularly offset and / or offset relative to the drive axis in the radial direction. A valve axis that is radially and angularly offset relative to the drive axis can be described as skewed relative to the drive axis.

[0012] The valve member can be arranged in a number of different locations within the pipe section (where the valve member completely closes the internal cross-section of the cubic section) or in locations that minimize the obstruction to the exhaust flow through the pipe section caused by the valve member. The valve member can be oriented within the pipe section to align with the centerline of the pipe section in order to minimize the flow resistance to the exhaust caused by the valve member, particularly the valve flap. The valve member can be positioned in several different locations, particularly between 0° and 90° relative to the centerline of the pipe section. In a preferred embodiment, the position of the valve member relative to the pipe section of the exhaust valve can be continuously variable, particularly in a stepless manner.

[0013] The coupling device is configured to transmit motion and / or torque from the drive shaft to the driven shaft. The coupling device itself defines an axis of rotation. The coupling device further includes a coupling rod received in a slot for translational movement of the rod relative to the retainer in the direction of the axis of rotation. The coupling rod can move parallel to the axis of rotation within the slot. The coupling rod is received in the slot in a backlash-free manner in the circumferential direction relative to the axis of rotation. Furthermore, the coupling device includes a resilient element, specifically a spring, which biases the coupling rod in the direction of the axis of rotation and has an attachment section fixed to the retainer. The resilient element may have a first end that is securely attached to the retainer at the attachment section of the resilient element. The attachment section of the resilient element may be the end of a spring. The fixed attachment of the resilient element to the retainer can be provided, for example, by welding, brazing, molding, forging, gluing, and similar methods. The coupling rod is biased by the resilient element in the direction of its translational mobility within the slot. Any displacement of the coupling rod within the groove in a first compression direction and / or a second tension direction parallel to the axis of rotation is counteracted by the biasing force of the elastic element. The coupling rod may be the second end of an elastic element (such as a spring). The axis of rotation of the coupling device is the axis around which its components rotate to transmit rotational movement from the drive shaft to the driven shaft. The axis of rotation of the coupling device is preferably oriented to be coaxially aligned with the drive shaft and the valve axis, or angularly offset but radially aligned (crossed) with the drive shaft and the valve axis. The coupling device compensates for any misalignment of the drive shaft's drive axis relative to the valve axis of the driven shaft.

[0014] The coupling device according to this disclosure includes a torsionally rigid retainer with an axially extending groove. It should be understood that the retainer provides sufficient rigidity so that operation of the exhaust valve does not cause deformation of the retainer. Any torque transmitted from the drive shaft to the driven shaft via the retainer causes negligible deformation of the retainer. The maximum force applied to the torsionally rigid retainer by the actuator causes a deformation of less than 1%, particularly less than 0.5%, preferably less than 0.1%, of the retainer relative to its axis of rotation. The retainer can be manufactured using one or more different manufacturing methods, including turning, milling, and / or sheet metal bending.

[0015] The retainer and coupling rod are non-rotatably connected. The coupling rod preferably has no rotational play in its corresponding slot. Any translational movement of the rigid member is similarly performed by the connecting rod, and vice versa. The coupling device according to this disclosure is configured such that any movement of the coupling rod about the axis of rotation is accompanied by the same rotational movement of the retainer about the axis of rotation. The coupling rod and retainer rotate as a single unit about the axis of rotation. Specifically, when the coupling device is connected to the exhaust valve and the actuator, when the drive shaft causes the retainer to rotate about the axis of rotation, the coupling rod performs the same rotational movement about the axis of rotation as the retainer, such that the coupling device can transmit rotational movement to the driven shaft. In a preferred embodiment, the retainer is attached to the drive shaft and the coupling rod can be attached to the driven shaft. Alternatively, the retainer can be attached to the driven shaft and the coupling rod can be attached to the drive shaft. In cases where the drive shaft is misaligned relative to the driven shaft, the coupling device can preferably be configured to act as a universal joint for connecting the drive shaft to the driven shaft.

[0016] The non-rotatable connection between the coupling rod and the retainer allows any change in rotational motion or position to be transmitted directly from the drive shaft to the driven shaft, even in the event of rapid changes in direction. This allows for quick and precise valve positioning while avoiding any rattling noise. Separating the coupling rod and retainer also allows the coupling device to thermally decouple the hot exhaust valve from the cold actuator while allowing for thermal expansion of the driven shaft.

[0017] Preferably, the elastic element is compressible in the axial direction. Alternatively or additionally, the elastic element is extensible in the axial direction. The elastic element may include a specific rod-shaped attachment segment at its first axial end and a coupling rod at its second axial end.

[0018] Specifically, the coupling device may include a resilient element, a coupling rod, and a retainer. The rod-shaped attachment segment or attachment rod may be oriented at an angle, preferably perpendicular to the coupling rod. The coupling rod may be oriented in a first intersecting direction relative to the axis of rotation of the coupling device, and the attachment rod may be oriented in a second intersecting direction. By arranging the attachment rod and the coupling rod at an angle relative to each other, the omnidirectional function of the coupling device can be enabled.

[0019] In embodiments of the coupling device, the slot has opposing edges, specifically extending parallel to and circumferentially opposite each other in a direction relative to the axis of rotation of the coupling device, to translately guide the coupling rod and to transmit torque from the coupling rod to the retainer. The edges of the slot are also configured to transmit torque from the retainer to the coupling rod. Preferably, the distance between the opposing parallel edges of the slot approximately corresponds to the outer width (preferably diameter) of the coupling rod. By providing slots with opposing guide edges spaced apart according to the width or diameter of the coupling rod, the position of the valve member can be precisely controlled by an actuator. The actuator can reach not only the open and / or closed end positions of the valve, but also any intermediate reset of the valve member. The edges of the slot can act as sliding supports for guiding the coupling rod.

[0020] The width of the edge can be the same as or greater than the width or diameter of the coupling rod. Preferably, the width of the edge is at least 0.2 times the width of the coupling rod, particularly at least 0.5 times, and preferably at least 0.8 times. Alternatively or additionally, the width of the edge is no greater than 5 times the width of the coupling rod, particularly no greater than 2 times, and preferably no greater than 1.5 times.

[0021] According to one embodiment of the coupling device, the resilient element attached to the retainer has no torque and / or no axial bias. The retainer and the resilient element are preferably adapted to each other such that they do not exert any torque, compression, or tension on each other in the static state of the coupling elements. Specifically, the coupling rod is received in a slot and / or the attachment section is secured to the retainer such that no torque and / or no axial force from the resilient element enters the retainer in the static state of the coupling device. The static state can specifically refer to the state where the fully assembled coupling device is not attached to the drive shaft and / or not attached to the driven shaft of the valve assembly. The retainer and the resilient element can be form-fitted to each other such that the coupling device assembly does not induce torque, compression, or tension bias. Alternatively, the retainer and the resilient element can be adapted to each other to apply biasing forces (such as tension or compression) to each other in the axial direction without torque.

[0022] In embodiments of the coupling device, the elastic member comprises, and is particularly composed of, a helical spring, particularly preferably having a narrow end fixed to the coupling rod and / or a wide end fixed to the attachment section, preferably the attachment rod. The retainer and the specific conical helical spring can be coupled to each other in a space-saving manner. The shape of the helical spring can be preferably determined by a first specific outer diameter at a first axial end of the helical spring, a second specific inner diameter at a second axial end opposite to the first end, the axial extension of the helical spring, and the width of the helical spring (particularly the thickness of the linear element). Specifically, the constant outer diameter and / or maximum outer diameter of the helical spring is at least 20 mm, at least 25 mm, or at least 30 mm. Alternatively or additionally, the constant outer diameter and / or maximum outer diameter of the helical spring is at most 60 mm, at most 50 mm, or at most 40 mm. In one embodiment, the constant outer diameter and / or maximum outer diameter of the helical spring can be 36 mm ± 1 mm. The width of the helical spring, particularly the thickness of the linear element, can be particularly constant. The width of the spring is particularly at least 1 mm, at least 1.5 mm, or at least 2 mm. The width of the spring is particularly at most 3.5 mm, at most 3 mm, or at most 2.5 mm. In particular, the width of the spring can be 2.5 mm ± 0.1 mm. Cylindrical helical springs can be configured to have an axial height of at most 30 mm, particularly at most 25 mm, or at most 15 mm. Cylindrical helical springs can be configured to have an axial height of at least 7.5 mm, particularly at least 10 mm, or at least 12 mm. Cylindrical helical springs can have a pitch of at least 1.5 and / or at most 5, particularly 2-4. Advantageously, the helical spring has a relatively small area quadratic moment when moving about its axis of rotation and can act as a thermal insulator in its axial direction to thermally separate the actuator from the exhaust valve. Helical springs are also advantageous because they can be designed to have almost no imbalance about the axis of rotation. Preferably, the helical spring is circumferentially surrounding the retainer relative to the axis of rotation of the coupling device.

[0023] In a preferred further improvement, the helical spring can be a conical helical spring, having a narrow end fixed to an attachment section (particularly an attachment rod) and a wide end fixed to a coupling rod. The conical helical spring is defined as having a conical shape, wherein the first end of the helical spring is wider than the second end. The maximum outer diameter of the conical helical spring may specifically correspond to the aforementioned dimensions of a general helical spring. The minimum inner diameter of the conical helical spring may be specifically arranged at the opposite axial ends of the spring end that achieves the maximum outer diameter. The minimum inner diameter of the conical helical spring is less than the maximum outer diameter minus the spring width. Specifically, the minimum inner diameter of the conical helical spring is at least 10 mm or at least 15 mm. Alternatively or additionally, the minimum inner diameter of the conical helical spring is not greater than 30 mm, not greater than 25 mm, or not greater than 20 mm. In particular, the minimum inner diameter of the conical helical spring is about 16 mm ± 1 mm. Conical helical springs can be configured to have an axial height of up to 30 mm, particularly up to 25 mm or up to 22.5 mm. Conical helical springs can be configured to have an axial height of at least 10 mm, particularly at least 15 mm or at least 20 mm. Conical helical springs can have a pitch of at least 2 and / or up to 10, particularly 4 to 6.

[0024] In a further improvement to the coupling device that can be combined with the above embodiments, the elastic element, particularly the helical spring, and the coupling rod are formed as a single piece, particularly as a single piece of a linear element preferably having a constant diameter. The coupling rod and the remaining elastic element (particularly the helical spring) can have a constant linear diameter along the entire extension of the linear element. A coupling device having an elastic element comprising an attachment rod as its attachment end, the coupling device may also have the same constant linear diameter as the coupling rod at the attachment rod. Preferably, the elastic element comprising the attachment rod and the coupling rod is formed as a single piece. In particular, the linear segment forming the straight coupling rod and the linear segment forming the straight attachment rod are arranged to intersect each other, particularly at an angle of 90°. The coupling rod and the attachment rod can alternatively be arranged parallel to each other. Preferably, the angle between the coupling rod and the attachment rod is less than 60°, particularly less than 30°, and most preferably less than 10°. Such a coupling device may specifically include a helical spring and a rigid retainer, the helical spring including a coupling rod.

[0025] According to an embodiment of the coupling device that can be combined with the foregoing embodiments, the retainer comprises a metal plate, specifically composed of a metal plate having a central section and two folds bent relative to the central section toward a first direction (preferably, a first direction parallel to the axis of rotation), wherein the two folds form grooves for retaining the coupling rod. Using a single metal plate to provide the retainer for the coupling device has shown to provide maximum torsional rigidity with minimal weight. The central element of the metal plate retainer may be flat and intersect the axis of rotation of the coupling device. The folds of the retainer may preferably extend parallel to the axis of rotation and be radially opposite to each other in a radial direction relative to the axis of rotation. An axially extending groove can thus be formed in the axially extending lobes. The coupling device may have a circumferential gap between the lobes to avoid unnecessary weight and improve thermal insulation. The lobes extending from the central portion of the rigid retainer can serve as a pair of guide posts surrounding the corresponding grooves in which the connecting rod is guided. The lobes forming the edges of the grooves can act as guide rails for the sled-like coupling rods arranged therebetween. Preferably, the retainer has two diametrically opposed slots for receiving a coupling rod, wherein the slots are arranged diametrically opposite each other relative to the axis of rotation to prevent imbalance in rotating the coupling rod about the axis of rotation. In such embodiments, the flaps of the retainer may also be positioned radially opposite each other relative to the axis of rotation to avoid imbalance. Preferably, the retainer has two opposing folds, each fold including a corresponding slot for receiving the same coupling rod. The retainer may include one or more gap spaces arranged circumferentially adjacent to one or more folds of the retainer. The gap spaces between circumferentially adjacent folds may have a circumferential extension at least as long as or greater than that of a corresponding adjacent fold. Preferably, at least 50%, at least 60%, or at least 75% of the circumferential extension of the retainer in a plane perpendicular to the axis of rotation A is achieved through one or more gap spaces between adjacent folds.

[0026] In another embodiment of the coupling device, the retainer comprises a metal plate, preferably composed of a metal plate, the metal plate having a central section and two seams that bend relative to the central section toward a second direction, preferably parallel to the axial direction, wherein the seams form at least one recess for retaining the attachment section. Preferably, the retainer has a central section from which two folded sections extend in a first direction, and the two seams extend from the central section toward a second direction different from the first direction (preferably opposite to the first direction). The central section may be designated as a saddle-shaped section. For ease of reference, the first direction may be designated as "downward," and the second direction may be designated as "upward." It should be understood that the coupling device with seams in all cases does not require any protrusions, such as folds, on the upper first side or in the central section. In the case where the attachment rod forms the attachment section, the recess may be designed to retain the attachment rod. The attachment section is preferably securely fixed to the seams of the retainer, for example by welding, molding, or gluing. The recess can be a U-shaped opening that extends opposite to the slot of the retainer. Alternatively, at least one or all of the recesses of the retainer can form a closed circular (O-shaped) opening that opens only in one direction intersecting the axis of rotation, such that the engagement of at least one recess with the shape-fitting attachment segment prevents any relative movement of the attachment segment (preferably an attachment rod) relative to the axis of rotation in a direction parallel to or circumferentially. The retainer may include one or more gap spaces arranged circumferentially near one or more seams. The gap spaces between circumferentially adjacent seams may have a circumferential extension at least as long as or greater than that of a corresponding adjacent seam. Preferably, at least 50%, at least 60%, or at least 75% of the circumferential extension of the retainer in a plane perpendicular to the axis of rotation A is achieved through one or more gap spaces between adjacent seams.

[0027] According to an alternative embodiment of the coupling device without seams, the coupling device can be compatible with one of the previously mentioned embodiments, wherein the retainer has a central plate section between the folds, wherein the central plate section is directly connected to the attachment section. Providing the retainer with a central plate section preferably passing through the axis of rotation allows the attachment section (in particular, the attachment rod) to be attached to or near the central plate section on the axis of rotation, for example, by welding, molding, or gluing. The central plate section of the retainer may be provided with attachment bridges, preferably straight, which can be arranged according to the attachment section, particularly the attachment rod, to allow mutual engagement of the attachment section and the attachment bridge with corresponding engagement portions of the drive shaft or driven shaft.

[0028] In alternative embodiments, the retainer may comprise or be composed of a hollow cylindrical body, specifically a cylindrical body with a constant diameter or a cylindrical body with graded diameters. A cylindrical body with graded diameters includes at least a middle section and a wide section, the middle section including a recess and the wide section including a groove. The hollow cylindrical body can be readily manufactured from a tubular body and can provide a high amount of torsional stiffness with relatively small wall thickness, while simultaneously having only a small area second moment. The hollow cylindrical body may have a cylindrical shape. Alternatively, the hollow cylindrical body may have at least two graded sections relative to each other, one with a narrow diameter and one with a wide diameter, wherein the narrow section includes at least one recess for retaining an attachment section of the resilient element, and wherein the wide section includes a groove for receiving a coupling rod. Specifically, in combination with a resilient element formed as a conical helical spring, a retainer with a graded cylindrical body allows for minimizing the required space for the coupling element. The graded cylindrical body may have one or more intermediate stages between narrow-diameter and wide-diameter sections. The wall strength of the hollow cylindrical body is preferably constant across all stages. The graded hollow cylindrical body may have a tapered shape that tapers from the narrow to the wide sections. The hollow cylindrical body may be sleeve-shaped with two opposing open ends and a through-hole therebetween, or it may be cup-shaped or can-shaped with sections closing either or both ends. The retainer may include one or more void spaces arranged circumferentially within the cylindrical body. The void spaces between adjacent recesses and / or grooves in the circumferential direction may have a circumferential extension at least as long as or greater than that of one, two, or more adjacent cylindrical body sections. Preferably, at least 50%, at least 60%, or at least 75% of the circumferential extension of the retainer in a plane perpendicular to the axis of rotation A is achieved through one or more void spaces between adjacent cylindrical body sections.

[0029] Specifically, the wall thickness of the metal plate retainer and / or the retainer having a cylindrical body is at least 0.5 mm, at least 0.75 mm, or at least 1 mm. The wall thickness of the retainer is particularly at most 3 mm, at most 2.5 mm, or at most 2 mm. Specifically, the wall thickness can be 1.5 mm ± 0.1 mm.

[0030] In a particular embodiment of the coupling device, the retainer includes at least one or more gap spaces extending along the direction of the rotation axis. Specifically, one or more gap spaces may extend between cylindrical body segments of a hollow cylindrical body. Alternatively, one or more gap spaces may extend between adjacent folds and / or seams. Preferably, the gap space between circumferentially adjacent folds, seams, or body segments may have a circumferential extension at least as long as or greater than that of a corresponding adjacent fold, seam, or body segment. The gap space serves as a cooling element and / or reduces the thermal mass of the retainer to improve thermal insulation between the coupling rod and the attachment segment.

[0031] Another aspect of the invention relates to a valve system comprising an actuator having a drive shaft, an exhaust valve having a driven shaft, and a coupling device connecting the driven shaft to the drive shaft with an axial clearance. The coupling device can be specifically configured as described above. The coupling device can provide axial clearance, radial clearance, and / or angular clearance, but no rotational clearance due to the connection between the driven shaft and the drive shaft, thus transmitting any rotational movement of the drive shaft about the drive axis to a corresponding rotational movement of the driven shaft about the valve axis. Preferably, the magnitude of the rotational movement of the drive shaft is converted into a corresponding, preferably identical, rotational movement of the driven shaft. The coupling member can act as a universal joint between the driven shaft and the drive shaft, thereby converting the rotational movement of the drive shaft into rotational movement of the driven shaft about the valve axis according to a predetermined motion function known to those skilled in the art. The coupling device provides a torque-resistant or rotationally rigid joint between the drive shaft of the actuator and the driven shaft of the exhaust valve, thereby allowing precise positioning of the exhaust valve components by the actuator and avoiding rattling noise.

[0032] In a further improvement to the valve system, the attachment segment of the resilient element and / or the retainer, fixed to a segment of the attachment segment, are connected to a drive shaft. In embodiments where the retainer includes a center plate segment, the center plate segment includes an attachment bridge, and both the attachment bridge and the attachment segment can be engaged by an engagement portion of the drive shaft to directly transmit rotational motion from the drive shaft to the attachment bridge and the attachment segment for the engaging movement of the retainer and the resilient element, without rotational backlash between the retainer and the resilient element. By directly coupling the attachment segment of the resilient element or the retainer to at least a corresponding segment of the resilient element connected to the drive shaft, rotational motion of the drive shaft can be directly transmitted to the coupling device.

[0033] In a further improvement to the valve system that can be combined with the aforementioned valve system, the system includes an adapter for form-fitting engagement of a drive shaft or driven shaft, particularly the engagement portion of the drive shaft or driven shaft, wherein the adapter surrounds an attachment segment of a resilient element. The adapter may surround the attachment segment completely or partially circumferentially, preferably as an attachment rod. The adapter may be an annular sleeve or a U-shaped bushing for providing a form-fitting engagement between the attachment segment and the drive shaft or driven shaft. Since the actuator may be a mass-produced electric motor, the engagement segment of the drive shaft may be formed to correspond to the electric motor manufacturer's standards, wherein different actuators from different manufacturers may have different dimensions. An adapter of a corresponding shape helps adapt the dimensions of the attachment segment (particularly the attachment rod) to the corresponding receiving portion on the drive shaft, the dimensions of which may be defined by the wire diameter of the spring coil. By placing an adapter between the attachment segment and the engagement segment of the drive shaft or driven shaft, true torque transmission without backlash can be provided in a simple manner. Alternatively or additionally, a coupling adapter may be provided to the coupling rod and the corresponding engagement section of the driven or driven shaft.

[0034] According to one embodiment of the valve system, the drive shaft and / or driven shaft achieves one or two corresponding contact lines with the corresponding engaging portion of the coupling device (particularly the coupling rod, attachment section, or retainer section fixed to the attachment section). The drive shaft or driven shaft may particularly achieve a single contact line with the corresponding portion of the coupling device (particularly the preferred threaded rod section of the coupling rod or attachment section). In a preferred embodiment, upper contact with the drive shaft is preferably achieved via a single contact line with the attachment section, and lower contact with the driven shaft is achieved via a single contact line with the coupling rod. Alternatively or additionally, the drive shaft or driven shaft may particularly achieve two radially opposing contact lines, wherein the retainer section is fixed to the attachment section. Preferably, upper contact between the coupling device and the drive shaft is achieved via two contact lines.

[0035] According to one embodiment of the valve system, torque is transmitted from the drive shaft to the driven shaft via a rigid retainer. Preferably, torque is transmitted exclusively from the drive shaft to the driven shaft via the rigid retainer. In particular, even when torque is transmitted from the drive shaft to the driven shaft, the elastic element remains without torque due to the transmission of torque via the rigid retainer. Specifically, the helical section of the coil spring may be without torque. For example, torque received at the coupling rod or attachment section is transmitted to the retainer and through the retainer to another of the attachment section or coupling rod, thereby reducing the torque experienced by the elastic element. When the torque-transmitting rigid retainer is attached to the shaft, the elastic element may be tensioned, particularly in the direction of the rotation axis. Alternatively, in the installed state of the valve system, the elastic element may remain without tension, particularly without compressive bias and / or stretchable bias.

[0036] The present invention also relates to a method for assembling a coupling device (such as the coupling device described above). The assembly method includes the following steps:

[0037] (a) A retainer is provided, the retainer including a groove and a recess;

[0038] (b) Provide a helical spring including a coupling rod and an attachment section;

[0039] (c) Assemble the coupling rod into the slot of the retainer; and

[0040] (d) Assemble the attachment section into the recess of the retainer.

[0041] Unlike the cumbersome and complex assembly methods of existing technologies, the design of the coupling device described above allows for particularly simple and quick attachment. Advantageously, the assembly according to the method described above can alternatively include performing step (c) before step (d) or step (d) before step (c). The assembly method can be performed by first assembling the coupling rod into the slot of the retainer and then assembling the attachment segment into the recess of the retainer. Alternatively, the assembly method can be performed by first assembling the attachment segment into the recess of the retainer and then assembling the coupling rod into the slot of the retainer. It may be advantageous to first assemble and possibly fix the coupling rod or attachment segment of the helical spring into the slot or recess of the retainer, thereby limiting the possibility of movement of the helical spring relative to the retainer, making it easier for the helical spring and the retainer to be manipulated relative to each other, for example, to apply tension to the spring to extend or compress it, thereby making it easier to assemble the other part (i.e., the attachment segment or coupling rod) into the corresponding receiving portion, recess or slot, or retainer.

[0042] In one embodiment, the retainer rotates within the coil spring between steps (c) and (d). It should be understood that the rotation of the retainer within the coil can occur after step (c) and before step (d) or after step (d) and before step (c). Preferably, the retainer can be rotated from a first axial alignment within the coil spring to a second axial alignment within the coil spring. For example, axial alignment of the coil spring and the retainer occurs when the axis of rotation of the retainer is aligned (preferably coaxially aligned) with the axis of symmetry of the coil spring. By placing the retainer within the coil spring, the overall area second momentum of the coupling device is reduced by bringing the relatively rigid, bulky retainer closer to the axis of rotation of the coupling device. Simultaneously, arranging the coil spring outside the retainer, around the retainer, allows for greater flexibility of the coil spring for elongation in the axial direction and contraction in the radial direction, or, for example, in the case of a conical coil spring, because subsequent windings of the coil spring can be radially received within each other in a helical manner, allowing for a greater range of elastic deformation of the coil spring relative to the overall dimensions of the coupling device in the axial direction. Providing a retainer within the helical spring allows the coupling device to be made into a lightweight and compact design overall.

[0043] According to a further improvement of the assembly method, before, during, and / or after rotation, the retainer is translated at least once along its axis along the attachment section or along the coupling rod. The assembly method may utilize the case where the slot receiving the coupling rod and / or the recess receiving the attachment section are equipped with openings extending longitudinally in the axial direction of the retainer. The coupling rod and the slot may undergo translational relative movement relative to each other in the axial direction of the retainer. Alternatively or additionally, during the assembly process, the attachment section and the recess undergo maximum translational movement relative to each other along the axis of the retainer. The relative movement of the retainer in the axial direction may occur fully or partially during rotation of the retainer within the helical spring, before the start of rotation, or after the completion of rotation. Preferably, the translational rotational movement of the retainer relative to the helical spring occurs, wherein the translational movement along the axis of the retainer and, preferably, the rotational movement around the attachment section or around the coupling rod within the helical spring are simultaneous. In particular, the helical spring may extend during rotation, preferably for the entire duration of rotation or for a portion of the time the retainer spends rotating within the helical spring. By allowing the retainer to move relative to the coil spring along its axis, it is possible to assemble a relatively large retainer within the coil and rotate it, thereby enabling a retainer structure with relatively high rigidity for the torsional rigidity transmission from the driven shaft to the drive shaft.

[0044] The present invention also relates to a method for assembling a valve system (such as the valve system described above). The valve system assembly method specifically includes the coupling device assembly method as described above. During the valve system assembly method, when the coupling device is attached to the actuator and the exhaust valve, the resilient element is preferably compressed and biased in the axial direction. The coupling device should be prepared before it is installed to the actuator or the exhaust valve. It may be preferred that the completed coupling device is first attached to the actuator and then subsequently attached to the exhaust valve, or vice versa. After the coupling device is attached to one of the actuators or the exhaust valve, the coupling device is compressed before being attached to the other of the exhaust valve or the actuator. In one embodiment, after the coupling device has been attached to both the actuator and the exhaust valve, the resilient element of the coupling device may remain compressed and biased. In another preferred embodiment, after being attached to both the actuator and the exhaust valve, the resilient element of the coupling device is allowed to depressurize, such that no compression bias remains, or a substantially compression bias of less than 10%, preferably less than 1%, remains. Attached Figure Description

[0045] Further embodiments, features, and technical aspects are described in the dependent claims. Further details of preferred embodiments of the invention are illustrated in the accompanying drawings, in which:

[0046] Figure 1 An example of a valve system according to the invention is shown, the valve system including an actuator, an exhaust valve and a coupling device;

[0047] Figures 2a to 2c Different views of a first embodiment of the coupling device according to the present invention are shown;

[0048] Figures 3a to 3f A series of accompanying figures are shown, illustrating the... Figures 2a to 2c Assembly of coupling devices;

[0049] Figure 4a A view of a second embodiment of the coupling device according to the present invention is shown;

[0050] Figures 5a to 5c A third embodiment of the coupling device according to the present invention is shown;

[0051] Figures 6a to 6b A fourth embodiment of the coupling device according to the present invention is shown;

[0052] Figures 7a to 7f It shows that according to Figures 6a to 6b The assembly sequence of the coupling device;

[0053] Figure 8a A coupling device with an adapter is shown;

[0054] Figure 8bIt shows Figure 8a The adapter used;

[0055] Figure 8c Showing alternative adapters;

[0056] Figure 9a , Figure 9b It shows that it has the following characteristics: Figure 5a The valve device of the coupling device; and

[0057] Figure 10 It shows that it has the following characteristics: Figure 2a A schematic cross-sectional view of the valve assembly of the coupling device shown. Detailed Implementation

[0058] In the following description of a preferred embodiment of the valve system or coupling device according to the invention, the same or similar reference numerals are used to refer to the same or similar components.

[0059] The coupling device according to the invention is generally indicated by reference numeral 1. The coupling device 1 includes a torsional rigid retainer 2 and an elastic element 4 as its main components. The valve system according to the invention is generally indicated by reference numeral 7. This valve system includes an actuator 3, an exhaust valve 5, and the coupling device 1 as its main components.

[0060] exist Figure 1 In the exemplary embodiment shown, the valve system 7 includes a coupling device 1 inserted between the actuator 3 and the exhaust valve 5 for transmitting rotational motion from the actuator 3 to the exhaust valve 5. The actuator 3 has a drive shaft 31. The exhaust valve 5 has a driven shaft 51. The coupling device 1 connects the drive shaft 31 to the driven shaft 51 to transmit force and / or motion from the actuator 3 to the exhaust valve 5.

[0061] The coupling device 1 provides axial clearance to allow for thermal expansion of the exhaust valve, etc. Specifically, the coupling device 1 can be configured as a cardanic element to compensate for any radial misalignment between the rotation axis A3 of the drive shaft 31 and the rotation axis A5 of the driven shaft 51. That is, if the axis A3 of the actuator 3 is not coaxially aligned with the axis A5 of the exhaust valve 5, but is offset in the radial direction, this radial misalignment can be compensated by the coupling device 1.

[0062] Alternatively or additionally, the valve coupling device 1 can be configured to compensate for the angular misalignment between the rotation axis A3 of the actuator 3 and the rotation axis A5 of the exhaust valve 5. For example, if the rotation axis A5 of the valve is tilted or skewed relative to the axis A5 of the actuator 5, the coupling device 1 compensates for the misalignment and connects the valve 5 to the actuator 3 in a preferably non-rotational manner.

[0063] The non-rotatable connection between two components (such as drive shaft 31 and driven shaft 51) allows the two non-rotatable connected components to rotate relative to each other with no rotational clearance. When one of the several non-rotatably coupled components rotates relative to a reference object, the other non-rotatably coupled components also perform a forced rotational movement relative to the reference object.

[0064] When the drive shaft 31 and driven shaft 51 are non-rotatably coupled to each other, any and all rotation of the drive shaft 31 causes a corresponding rotational movement of the driven shaft 51, and vice versa. Those skilled in the art will understand that in the event of a significant misalignment of the actuator axis A3 relative to the axis A5 of the valve 5, the corresponding rotational movements of shafts 31 and 51 are determined by the characteristics of the universal joint connection between them. Because this non-rotatable connection has no play, it prevents any rattling noise caused by loosening of the exhaust valve 5.

[0065] The first embodiment of the coupling device 1 is in Figure 2a Shown in sectional view and in Figure 2b and Figure 2c The figures are shown in two different perspective views. In this embodiment, the elastic element 4 of the coupling device 1 is implemented as a hollow cylindrical helical spring 41. The helical spring 41 has a first end that realizes the attachment section 42. The second end of the helical spring 41 realizes the coupling rod 45.

[0066] A torsional rigid retainer 2 is coupled to an elastic element 4. The retainer 2 comprises a hollow cylindrical body 28 with graded diameters. In this embodiment, the cylindrical retainer within the body 28 has a narrow section 81 and a wide section 83. The wall thickness of the cylindrical body 28 is approximately constant. The inner diameter d1 of the narrow section 81 is smaller than the inner diameter d3 of the wide section 83. The cylindrical body 82 includes a tapered stepped section 82 connecting the narrow section 81 to the wide section 83. The wide section 83 has an axial extension along the rotation axis A of the retainer 2 that is larger than both the narrow section 81 and the tapered section 82, preferably at least as large as the combined axial extension of the narrow section 81 and the tapered section 82. The cylindrical body 28 may be provided with one or more empty sections, for example, in the cylindrical body section forming the wide section 83 and / or in the cylindrical body section forming the narrow section 81 (not shown).

[0067] The narrow section 81 includes a circular recess 24 that can circumferentially completely surround the attachment section 42 received therein. Optionally, the retainer 2 may additionally include a U-shaped axially opening recess 24'. The opening recess 24' can be arranged radially opposite to the recess 24. The attachment section 42 of the elastic element 4 can be fixed to the retainer 2 by welding. The attachment section 42 is inserted into the recess 24 of the retainer 2, and the elastic element 4 is fixed to the retainer 2, and the recess 24 receives the attachment section 42 to prevent relative movement of the elastic element 4 and the attachment section 42 relative to the retainer 2.

[0068] Once the attachment section 42 of the elastic element 4 is fixed to the retainer 2, only the coupling rod 45 remains movable relative to the retainer 2.

[0069] As indicated by arrow m, the coupling rod 45 of the elastic element 4 can move parallel to the axial direction A defined by the retainer 2 of the coupling device 1. However, in the circumferential direction relative to the axis of rotation A of the coupling device 1, the coupling rod 45 is prohibited from rotating relative to the retainer 2. The coupling rod 45 is received within the groove 25 of the retainer, such that the rod 45 can only move relative to the retainer 2 in a direction parallel to the axis of rotation A. When torque is applied to the coupling rod, the coupling rod 45 transmits the torque to the edge 27 of the groove 25. The edges 27 of the groove 25 are arranged opposite each other in the circumferential direction about the axis of rotation A and are spaced apart from each other by a distance corresponding to the width of the coupling rod 45. The coupling rod 45 is guided by the edges 27 of the groove 25, such that the coupling rod 45 can move in the direction of the axis of rotation A, but not in the circumferential direction relative to the axis of rotation A. The edges 27 of the groove 25 can act as sliding bearings for the coupling rod 45.

[0070] When the elastic element 4 is fixed to the retainer 2 at its attachment section 42, for example by welding, gluing, overmolding, or similar means, and when the coupling rod 45 is received substantially without play within the groove 25, the elastic element 4 is non-rotatably connected to the rigid retainer 2. Therefore, any torque applied to the coupling rod 45 or attachment section 42 by external influences is transmitted to the torsional rigid retainer. For example, when torque is received by the coupling rod 45, it is transmitted through the edge 27 of the groove 25 and to the body of the retainer 2. The retainer is designed to be torsional rigid such that no torsional deformation of the retainer 2 occurs, at least during normal operation. Preferably, the retainer 2 is designed to be torsional rigid enough that the maximum torque that the actuator 3 can provide to the coupler 1 via the drive shaft 31 causes a torsional deformation of the retainer 2 of less than 0.1% or less than 0.01%. The torque received by the retainer 2 from the coupling rod 45 can be transmitted to the attachment section 42 via the retainer body 28.

[0071] A groove 25 is arranged in the wide section 83 of the retainer 2. The axial extension of the groove 25 within the cylindrical body 28 of the retainer 2 is greater than the axial width (preferably diameter) of the coupling rod 45, particularly at least 1.5 times or at least 2 times the axial width of the coupling rod 45. The axial extension of the groove 25 within the cylindrical body 28 of the retainer 2 is less than 10 times, preferably less than 5 times, and more preferably less than 3 times the axial width (preferably diameter) of the coupling rod 45. The axial extension of the groove 25 within the bottom of the retainer 2 is less than half the axial extension of the retainer 2. In the assembled state of the coupling device 1, preferably the assembled state of the valve system 7, the coupling rod 45 is fully received within the groove 24 in the direction of the rotation axis A. It should be understood that the terms "direction of the rotation axis" and "axial direction" are used synonymously in this disclosure.

[0072] Figures 3a to 3f The diagram illustrates the sequence for attaching the elastic element 4 to the retainer 2, thereby assembling the coupling device 1. Figure 3a The separate components of the coupling device are shown, including its torsional rigidity retainer 2 before assembly and its adjacent elastic elements 4.

[0073] In this embodiment, the elastic element 4 is implemented as a cylindrical helical spring 41 with two end segments, the two end segments being ends relative to the helical spring body of the helical spring 41, such that the ends extend radially in general relative to the rotation axis A4 of the helical spring 41. The first end of the helical spring 41 forming the attachment segment 42 extends inward from the helical spring rod in a straight, rod-like manner. The second end realizing the coupling rod 45 has a segment 48 extending radially inward in a straight rod-like manner and an arcuate segment 47 additionally realized in the curved portion between the rod segments 48.

[0074] The straight rod section 48 of the coupling rod 45 and the straight rod portion forming the attachment section 42 are arranged relative to each other at a preferably orthogonal angle. The straight attachment section extends relative to the axis of rotation A in a first radial direction, and the straight rod section 48 of the coupling rod 45 extends relative to the axis of rotation A in a second radial direction. This arrangement of the coupling rod 45 relative to the attachment section 42 helps to allow the coupling device 1 to function as a universal joint.

[0075] Figure 3b A retainer 2 is shown disposed on top of the coupling rod 45 of the elastic element 4, wherein the straight section 48 of the coupling rod 45 is received in a groove 25 in the wall of the cylindrical body 28 of the retainer 2, the grooves being radially opposite each other relative to the rotation axis A2 of the retainer. Figure 3bAs shown, when the retainer 2 is disposed on top of the elastic element 4, the rotation axis or symmetry axis A4 of the elastic element 4 and the rotation axis A2 of the retainer 2 can be coaxially aligned. At this time, during the assembly of the coupling device 1, the attachment section 42 has not yet been received in the recesses 24, 24'.

[0076] Figure 3c The diagram illustrates how the retainer 2 rotates within the helical spring 41 about the coupling rod 45. The helical spring 41 has a constant outer diameter of approximately 36 mm. The hollow cylindrical body 28 of the retainer 2 has graded diameters to result in a narrow section 81, a conical section 82, and a wide section 83, as described above. During rotation of the retainer 2 within the helical spring 41 about the coupling rod 45, an arcuate section 47 ensures that the retainer does not slip radially off the coupling rod 45. The arcuate section 47 has an extension of approximately 180° around the axis of rotation A. The arcuate section 47 and the rod section 48 are formed from the helical spring wire and have the same thickness as the rest of the helical spring 41, approximately 1.5 mm. The outer diameter of the arcuate section is approximately 17 mm.

[0077] Figure 3d It is shown that the retainer 2 has been rotated about the coupling rod 45, such that a section of the retainer body 28 (in this case, the narrow section 81, which initially points away from the attachment section 42) now points towards the attachment section 42. Although the retainer 2 is in Figure 3b The stage shown is mainly located outside the coil spring 41, but it is in Figure 3d The stage shown is mainly arranged within the helical spring 41. When the attachment section 42 is not inserted into the corresponding recess 42, the spring 41 can extend along the direction of the rotation axis A.

[0078] Figure 3e It shows that it is in the same position as Figure 3d The elastic element 4 and the retainer 2 are in roughly the same state. The attachment segment 42 is not fully inserted into the corresponding recess 24, so that the axis A2 of the retainer is slightly inclined relative to the axis of the spring A4. In order to insert the attachment segment 42 into the recess 24, the attachment segment can be biased outward toward the coil spring 41, so that the end of the coil spring 41 forming the attachment segment 42 can then slide radially into the recess 24. Afterward, the attachment segment 42 can be firmly attached and thus fixed to the retainer 2.

[0079] Figure 3f The final assembled state of the coupling device 1 is shown, wherein the attachment segment 42 is received within the recesses 24, 24' of the retainer 2 and wherein the coupling rod 45 is arranged within the slot 25. At this stage, the rotation axis A2 of the retainer and the rotation axis A4 of the spring can be concentrically aligned to achieve the rotation axis A of the coupling device 1.

[0080] Different embodiments of coupling device 1 Figure 4a It is shown in sectional view in Figure 4, and in two different perspective views in Figures 4b and 4c. According to Figure 4a The coupling device 1 can be assembled according to the previously described method. Figures 2a to 3f The coupling device is assembled in the same manner. Alternatively, in order to... Figure 4a The elastic element 4 and retainer 2 of the coupling device 1 are assembled to each other. First, their attachment sections can be placed into the recess 24. Then, the retainer 2 can be rotated within the helical spring 43, allowing the coupling rod 42 to be inserted into the corresponding slot 25. The following is about... Figures 6a to 7e The coupling device shown describes such an assembly method.

[0081] exist Figure 4a In the illustrated embodiment, the shapes of the retainer and elastic element 4 differ slightly from those in the aforementioned embodiments, but according to... Figure 4a The function and structure of the coupling device 1 correspond to the function and structure of the aforementioned embodiment. In addition to the recess 24 and the groove 25, the cylindrical body 29 also has a void space 64 extending through the cylindrical body 29 in the axial direction A. The void space 64 separates the body section of the cylindrical body 29 in the circumferential direction and acts as a heat insulation barrier for insulating the attachment section 42, which can be attached to the thermal valve, from the coupling rod 45, which can be attached to the drive actuator.

[0082] The retainer 2 comprises a hollow cylindrical body 29 having a continuous, constant inner diameter and outer diameter. The width of the wall of the hollow cylindrical body 29 is approximately the same as the width of the wire forming the helical spring 40. The wall strength of the hollow cylindrical body 29 can be between 0.5 times and 2.5 times the width of the wire forming the helical spring 43.

[0083] according to Figure 4a In the embodiment of the coupling device 1 shown, the elastic element 4 is implemented as a conical helical spring 43, which slopes from a wide end toward a narrow end. The helical spring 43 terminates at the wide end in an attachment section 42 and at the narrow end in a coupling rod 45. The wide end of the conical helical spring 43 has an outer diameter of approximately 35.5 mm. The narrow end of the conical helical spring 43 has an inner diameter of approximately 16.5 mm. The width or diameter of the wire forming the helical spring 43 is approximately 1.5 mm. Figure 4a In the embodiment shown, both the coupling rod 45 and the coupling segment 42 of the elastic element 4 include straight rod segments 48. The rod segments 48 that form the attachment segment 42 on the one hand and the coupling rod 45 on the other hand extend perpendicularly to each other, so that the coupling device 1 can act as a directional joint element.

[0084] Figure 5a A third embodiment of the coupling device 1 is shown. Figure 5a The elastic element 4 of the coupling device 1 shown is the same as that previously described Figures 2a to 3f The elastic elements in the embodiments shown are substantially the same.

[0085] The retainer 2 is implemented as a curved metal plate body, which includes a fold 23 that is curved in the direction of the rotation axis A. Figures 5a to 5c The metal plate shown has a first central section 20 extending in a radial plane relative to the axis of rotation A, and two folded sections 23a protruding from the central section 20 in the direction of the axis of rotation A.

[0086] like Figure 5a The coupling device 1 shown has a retainer comprising a metal plate. A central segment 20 is fixed to an attachment segment 42 of the elastic element 4. The central segment 20 can be securely attached to the attachment segment 42 of the elastic element 4, for example, by welding, gluing, or otherwise. Figure 5a In the exemplary embodiment shown, the elastic element is implemented as a helical spring 41 with a constant diameter. The elastic element 4, its attachment segment 42, and its coupling rod 45 are made of a wire with a constant diameter. Figure 5a The elastic element 4 in the embodiment shown generally corresponds to Figures 2a to 3f The elastic element of the embodiment shown.

[0087] The central section 20 of the metal plate retainer 2 has a bridging section 20a, which is surrounded by holes 21 on two opposite sides. The bridging section 20a of the central section 20 passes through the axis of rotation A and has a width corresponding to the width of the attachment section 42. The holes 21 on both sides of the bridging section 20a allow the engagement section of the drive shaft to engage both the bridging section 20a and the attachment section 42 of the elastic element, for example, through the holes 21, to transmit torque between the shaft and the coupling device 1 without generating torsional stress between the elastic element attachment section 42 and the corresponding section of the retainer 2 (to which the attachment section 42 is fixed). In this case, the bridging section 20a... Figure 5c As can be seen, the straight rod-shaped end of the helical spring 41 forming the attachment section 42 is aligned parallel to the bridging section 20a that extends radially relative to the axis of rotation A.

[0088] The metal plate has a thickness similar to the width of the linear portion of the coil spring 41. The width of the folded section 23a of the metal plate retainer 2 in the circumferential direction about the axis of rotation A is no more than 10 times the width of the coupling rod 45, preferably no more than 5 times the width of the coupling rod 45, and a gap space 65 exists between the opposing folded sections 23a.

[0089] Figure 6aA cross-sectional view of another embodiment of the coupling device 1 is shown. Figure 6a The coupling device 1 in Figure 6b Shown in different views, and used for Figure 6a The assembly steps of the coupling device 1 are as follows: Figures 7b to 7e As shown in the image.

[0090] Figure 6a The recess 24 of the retainer 2 shown is angledly surrounded by the metal plate body, such that the attachment segment 42 can encounter two opposing limiting stops in the direction of the rotation axis. The upper limiting stop and / or the lower limiting stop can facilitate the assembly of the attachment segment 42 to the retainer 2, particularly for torque-resistant fixing.

[0091] Figure 6a The elastic element 4 in the coupling device 1 is implemented as a conical helical spring 43. Figure 6a The helical spring 43 tapers from the end of the rod-shaped straight end 48 that realizes the attachment section 42 toward the end of the rod-shaped straight end 48 that realizes the coupling rod 45. Regarding the elastic element 4, therefore refer to the section on... Figure 4a The embodiments shown are described below.

[0092] Figure 6a The retainer 2 of the illustrated embodiment is implemented as a metal plate having two folded portions 23b bent in a first upward direction and provided with a groove 25 for receiving a coupling rod. The metal plate component implementing the retainer 2 further includes two seam portions 22b bent in a second downward direction (opposite to the first direction), with recesses 24 provided in the seam portions 22b for receiving an attachment segment 42 of an elastic element. Those skilled in the art will envision that the metal plate implemented in the retainer 2 can be shaped into a generally cross-shaped form before bending, wherein two diameter-opposite arms of the cross are bent in the first direction, and wherein the remaining two diameter-opposite arms are bent in the second direction. The retainer 2 has a central segment 20, from which the folded portions 23b extend upward, and seam portions 226 extend downward from the central segment 20.

[0093] exist Figure 7a In the image, the retainer itself is shown near the conical helical spring 43. Preferably, the diametrically opposed folds 23b are formed with respect to each other in a mirror-symmetric manner; similarly or alternatively, the diametrically opposed seams 22b of the retainer 2 are preferably formed with respect to each other in a mirror-symmetric manner. The symmetry of the folds 23b and / or seams 22b of the retainer 2 can advantageously reduce imbalance.

[0094] Each of the folding portions 23b is provided with a slot 25 for receiving the coupling rod 45. Figure 6aIn this design, the slot 25 is U-shaped and open in the direction of the rotation axis A to allow the coupling rod 45 to be easily inserted into the retainer. The fold 23b forms spaced edges 27 corresponding to the width of the coupling rod 45. The edges 27 of the slot serve as guides for the coupling rod 45 in a purely translational manner relative to the metal plate body of the retainer 2. Therefore, if torque is applied to the coupling rod 45, for example, from the corresponding coupling segment of the drive shaft 31 or driven shaft 51, the torque can be directly transmitted from the coupling rod 45 to the retainer 2 without any play.

[0095] Figure 7a The retainer 2 is shown in its pre-assembled state near the elastic element 4. As a first assembly step, according to... Figure 7b The rod-shaped attachment section 42 of the helical spring 43 can be inserted into the recess 24 of the joint 22b. Figures 6a to 7e In the embodiment shown, the recess 24 for receiving the attachment segment 42 provides clearance for the attachment segment 42 to move in the direction of the rotation axis A during assembly. The recess 24 may also be sized to include clearance in the circumferential direction relative to the rotation axis a of the retainer 2 during assembly. In the direction of axis a of the retainer 2, the attachment segment 42 can move several times its width (preferably its diameter), such as two or three times its width. Figure 7b and Figure 7c Between the assembled states shown, the attachment section 42 has moved within the recess 24 in the direction of the rotation of the retainer A2, thereby sliding these seam portions 22b into the space surrounded by the spring 43.

[0096] Figure 7d The rotation of the retainer 2 around the attachment segment 42 within the helical spring 43 is shown. Figure 7e The retainer 2 is shown from Figure 7c The position shown has rotated approximately 100° with respect to the attachment segment 42. Figure 7c and Figure 7e Between the states shown, the attachment segment 42 remains within the recess 24 in the joint portion 22b. Although in Figure 7b and Figure 7c The initial fold 23b points outward from the helical spring 43 and away from the coupling rod. Figure 7e The fold 23b pointing to the coupling rod 45 is shown. (As shown) Figure 3b As shown, the coupling rod 45 can be received within the slot 25.

[0097] The retainer 2 moves in the direction of its rotation axis A2 to reach, as Figure 7f The final assembly position is shown. The retainer 2 moves relative to the attachment section 42, causing the retainer 2 to slide further into the interior of the coil spring 43. Once the coupling rod 45 is received within the slot 25, as... Figure 6b As indicated, the attachment segment 42 is then securely attached to the retainer 2, for example by welding or brazing the attachment segment 42 to the joint 22b or by covering the molded joint 22b, or by some other means, to fix the attachment segment 42 non-rotatably relative to the retainer 2.

[0098] exist Figures 6a to 7f The retainer 2 shown in the figure (as can be, for example, from) Figure 6a It is readily apparent that the space can be created with very little material, thus leaving large circumferential gaps 65, 66 between the folds 23b and between the seams 22b. The gaps 65, 66 between adjacent circumferentially folds 23b or adjacent circumferentially folds 22b can have a circumferential extension at least as long as or greater than that of a corresponding adjacent fold 23b or seam. Preferably, at least 50%, at least 60%, or at least 75% of the circumferential extension of the retainer 2 in a plane perpendicular to the axis of rotation A is achieved through one or more gaps 65, 66 between adjacent folds 23b or seams 22b. Thus, the retainer 2 and the spring 43 attached to the retainer 2 form a very lightweight coupling device 1, which can be easily and precisely moved by the drive actuator 3 and serves as a highly efficient thermal insulator between the drive shaft 31 and the driven shaft 51.

[0099] Figure 8a Different embodiments of the coupling device are shown. The coupling device 1 includes a cylindrical helical spring 41 attached to a metal plate retainer 2, which includes a folded portion 23c extending in a first direction parallel to the rotation axis A of the coupling device 1 and a seam portion 22c extending in a second opposite direction. Figure 8a The retainer shown is similar to the one previously mentioned. Figures 6a to 7f The difference in the described retainer is that the seam portion 22c is shorter, and the recess 24 provided therein is formed in a manner similar to... Figure 2a The recesses shown in the embodiment.

[0100] It is worth noting that, Figure 8a A U-shaped bushing 53a is shown, which surrounds the attachment section 42 to serve as an adapter between the coupling device 1 and the driven or drive shaft engagement section (not shown in further detail). Figure 8b An exemplary embodiment of the U-shaped bushing is shown in the figure, and Figure 8c The cylindrical bushing 53b is shown in the figure.

[0101] exist Figure 9a and Figure 9b The valve assembly 7 shown in the figure shows the joint section 33 of the two radially opposite contact lines 72 of the coupling device 1. Figure 9aA side view of component 7 is shown. Figure 9b It shows that according to Figure 9a A cross-sectional view of line JJ. The driven shaft 51 is shown schematically. The engaging section 33 of the drive shaft 31 extends into the coupling device 1 through the hole 22 of the retainer 2. The engaging section 33 firmly grips the edge of the bridging section 20a of the retainer 2. The engaging section 33 does not directly contact the attachment section 42 or any other part of the elastic element 4. However, the engaging section 33 engages the retainer 2 at the section of the retainer 2 that is attached to the attachment section 42.

[0102] exist Figure 9a , Figure 9b and Figure 10 The force and / or torque transmission between the coupling device 1 and the actuator 3 in the embodiment shown is substantially the same. Although in an alternative embodiment the attachment segment 42 of the elastic element or the corresponding portion of the retainer 2 may preferably be attached to the drive shaft 31, the attachment segment or corresponding portion of the retainer 2 may be attached to the driven shaft 51.

[0103] Figure 10 A valve assembly 7 with an electric motor 3 is shown. The electric motor 3 has a drive shaft 31, and the drive shaft 31 has a connecting section 33. A driven shaft 5 is schematically shown. The end of the attachment section 42 of the elastic element 4 is located in the connecting section 33. A single contact line 71 is formed between the attachment section 42 and the drive shaft 31. Figure 10 The coupling device 1 shown corresponds to about Figure 2a The described coupling device. Alternatively, another coupling device, such as those described above, may be provided. Figure 4a , Figure 6a or Figure 8a The coupling device described herein. The attachment section 42 of the coupling device 1 is securely held by the engagement section 33. When the drive shaft 31 is rotated by the actuator 3, it forces the attachment section 42, and thus the entire coupling device 1, to perform a corresponding rotational movement. The engagement section 33 engages the coupling device 1 in a torque-resistant manner.

[0104] Figure 10 The engagement section 33 of the clamping attachment segment 48 is shown. This engagement may be form-fitted in the rotational direction relative to the axis of rotation A. Alternatively, a radial clamping force may be used to hold the coupling device 1 to the engagement section 33. Alternatively or additionally, an axial bias 4 of the elastic element 4 between the drive shaft 31 and the driven shaft 50 may help hold the coupling device 1 in place.

[0105] The features disclosed in the foregoing description, drawings, and claims are of great significance for implementing the invention individually and in any combination in various embodiments of the invention.

[0106] List of reference numerals

[0107] 1 Coupling device

[0108] 2 Torsional rigid retainer

[0109] 3 actuators

[0110] 4 elastic elements

[0111] 5 exhaust valves

[0112] 7-valve system

[0113] 20 central section

[0114] 20a Bridge Section

[0115] 21 holes

[0116] 22b joint

[0117] 22c seam

[0118] 23a Folding section

[0119] 23b Folding section

[0120] 23c folding section

[0121] 24 recesses

[0122] 25 slots

[0123] 27 Edge

[0124] 28 cylindrical bodies

[0125] 29 cylindrical body

[0126] 31 drive shafts

[0127] 33 Joint Section

[0128] 41 helical spring

[0129] 42 Attachment Section

[0130] 43 helical spring

[0131] 45 coupling rod

[0132] 47 Arc-shaped section

[0133] 48 Straight rod section

[0134] 51 driven shaft

[0135] 53 U-shaped bushing

[0136] 64 gap space

[0137] 65 gap space

[0138] 66 gap space

[0139] 71 contact line

[0140] 72 contact line

[0141] 81 Narrow Section

[0142] 82-step section

[0143] 83 wide section

[0144] Axis A

Claims

1. A coupling device (1) for connecting a drive shaft (31) of an actuator (3) to a driven shaft (51) of an exhaust valve (5), the coupling device (1) defining a rotation axis (A), and the coupling device (1) comprising: Torsional rigid retainer (2), the torsional rigid retainer (2) having an axially extending groove (25). A coupling rod (45), which is received in the slot (25), is used for translational movement relative to the retainer (2) in the direction of the rotation axis (A). An elastic element (4) biases the coupling rod (45) in the direction of the rotation axis (A) and has an attachment section (42) fixed to the retainer (2); wherein the retainer (2) and the coupling rod (45) are non-rotatably connected, characterized in that, The elastic element (4) includes a conical helical spring (43) having a narrow end fixed to the coupling rod (45) and / or a wide end fixed to the attachment segment (42). The retainer includes a hollow cylindrical body (28) having graded diameters, the cylindrical body (28) including at least a narrow section and a wide section, the narrow section including a recess (24) and the wide section including the groove (25).

2. The coupling device according to claim 1, wherein, The coupling rod (45) has no rotational clearance in the corresponding slot (25).

3. The coupling device according to claim 1 or 2, wherein, The groove (25) has edges (27) that are opposite each other in the circumferential direction relative to the axis of rotation (A) of the coupling device (1), and the edges (27) extend parallel to the axis of rotation (A) of the coupling device (1) for translatively guiding the coupling rod (45) and for transmitting torque from the coupling rod (45) to the retainer (2).

4. The coupling device according to any one of the preceding claims, wherein, The elastic element (4) and the coupling rod (45) are formed as a single piece as a linear object with a constant diameter.

5. The coupling device according to any one of the preceding claims, wherein, The retainer (2) includes at least one gap space (64, 65, 66) extending along the direction of the rotation axis (A), the at least one gap space (64, 65, 66) being between cylindrical body segments of the hollow cylindrical body (28, 29) or between adjacent folds (23a, 23b, 23c) and / or seams (22b, 22c).

6. A valve system (7) comprising an actuator (3) having a drive shaft (31), an exhaust valve (5) having a driven shaft (51), and a coupling device (1) according to any one of the preceding claims, the coupling device non-rotatably connecting the driven shaft (51) to the drive shaft (31) with axial clearance.

7. The valve system (7) according to claim 6, wherein, The attachment section (42) or the section of the retainer (2) fixed to the attachment section (42) is connected to the drive shaft (31).

8. The valve system (7) according to claim 6 or 7, further comprising adapters (53a, 53b) for form-fitting engagement of the drive shaft (31) or the driven shaft (51), wherein, The adapter surrounds the attachment section (42).

9. The valve system (7) according to any one of claims 6 to 8, wherein, The drive shaft (31) and / or the driven shaft (51) achieve one or two corresponding contact lines (71, 72) with the corresponding engagement portion of the coupling device, and achieve the one or two corresponding contact lines (71, 72) with the coupling rod (45), the attachment section (42) or the section of the retainer (2) fixed to the attachment section (42).

10. The valve system (7) according to any one of claims 6 to 9, wherein, Torque is exclusively transmitted from the drive shaft (31) to the driven shaft (51) through the rigid retainer (2), such that the elastic element (4) is kept without torque, wherein the elastic element (4) is taut or tensionless in the direction of the rotation axis (A).

11. The valve system (7) according to any one of claims 6 to 10, wherein, The coupling device (1) connects the driven shaft (51) to the drive shaft (31) with an axial clearance but no rotational clearance.

12. A method for assembling the coupling device (1) according to any one of claims 1 to 5, comprising the following steps: a) Provide a retainer (2) comprising a groove (25) and a recess (24, 24'); b) Provide a helical spring (41, 43) including a coupling rod (45) and an attachment section (42); c) Assemble the coupling rod (45) into the slot (25) of the retainer (2); as well as d) The attachment segment (42) is fitted into the recess (24, 24') of the retainer (2).

13. The method according to claim 12, wherein, Between step c) and step d), the retainer (2) rotates within the helical springs (41, 43).

14. The method according to claim 13, wherein, Before, during and / or after the rotation, the retainer is moved at least once along the axis of the retainer along the attachment section (42) or along the coupling rod (45).

15. A method for assembling a valve system (7) according to any one of claims 6 to 11, comprising the assembly method according to any one of claims 12 to 14, wherein, When the coupling device (1) is attached to the actuator (3) and the exhaust valve (5), the elastic element (4) is compressed and biased in the axial direction (A).

Images