Adjustment and comfort drive for actuators in the automotive field
Patent Information
- Application Number
- PCT/DE2026/100184
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-02-22
- Filing Date
- 2026-02-17
- Publication Date
- 2026-08-27
Smart Images
Figure DE2026100184_27082026_PF_FP_ABST
Abstract
Description
[0001] Attorney file: 524011 -PCT
[0002] Applicant: Framo Morat GmbH & Co KG
[0003] Franz-Morat-Straße 6
[0004] 79871 Eisenbach
[0005] Title: Adjustment and comfort drive for actuators in the automotive sector
[0006] DESCRIPTION
[0007] The invention is based on an adjustment and comfort drive for actuators in the automotive sector.
[0008] The automotive sector covers all branches of the automotive industry. Adjustment and comfort drives for actuators in the automotive sector are used, for example, for the following purposes: seat adjustment, adjustment and folding of exterior mirrors, steering wheel adjustment, opening and closing of the tailgate, charging port, or sunroof, door opening and closing assistance, roof shading, power windows, windshield and rear window wipers, lights, sensors and cameras, and locking and unlocking of charging plugs. An adjustment and comfort drive includes a gearbox. This gearbox must be compact, lightweight, and highly efficient. It should also operate quietly.
[0009] Such a comfort drive for moving an element in a motor vehicle, such as a sunroof, a seat, or a window, is known from DE 102019220 165 A1. The comfort drive has a drive worm that is rotated by a motor. The drive worm engages with a worm wheel with spur teeth. The drive worm engages the outer circumference of the worm wheel and transmits the motor's torque to the worm wheel. The distance between a geometric axis of the worm, around which the drive worm is rotated, and a geometric axis of the worm wheel, around which the worm wheel is rotated, is greater than the outer radius of the worm wheel. This results in a large overall size for the comfort drive.
[0010] The invention is based on the objective of providing an adjustment and comfort drive for actuators in the automotive sector which, compared to the prior art, has a reduced size while offering high efficiency, low weight and low noise levels, and simplifies assembly.
[0011] This problem is solved by an adjustment and comfort drive with the features of claim 1. The drive is characterized by being equipped with a cylindrical worm and a face gear. The worm has at least one thread on its circumferential surface. It is driven to rotate about a geometric worm axis. The face gear has helical teeth on its face. The worm engages with the face gear such that its at least one thread meshes with the teeth of the face gear, and the worm thereby drives the face gear to rotate about a geometric face gear axis. The worm and the face gear are aligned with each other such that the geometric worm axis and the geometric face gear axis are skew geometric lines whose distance d is less than an outer radius of the face gear.The distance here is meant in a mathematical sense: the distance d is the shortest connection between these geometric lines. The worm gear is driven, for example, by a motor or manually. Additional gear stages can be provided between the motor or manual drive on the one hand and the worm gear on the other. The torque of the drive is transmitted to the worm gear and from there to the face gear.
[0012] Since the worm gear does not engage the gear circumferentially, but rather on its face, the distance between the geometric axis of the worm gear and the geometric axis of the face gear is smaller than the outer radius of the face gear and therefore also smaller than in the prior art comfort drive. This results in a smaller overall size. Furthermore, it allows for space-saving integration of the adjustment and comfort drive at its point of use in the automotive sector.
[0013] Due to the cylindrical worm and the face gear, there is one degree of freedom in the direction of the geometric worm axis during the assembly of the adjustment and comfort drive. Robustness against deviations in the arrangement of the worm relative to the face gear is increased in the direction of the geometric worm axis. This simplifies the assembly of the adjustment and comfort drive.
[0014] The cylindrical worm and the face gear have a high contact ratio. Several turns of the worm are always engaged with the helical teeth of the face gear. This results in a high power density during torque transmission.
[0015] Furthermore, the combination of a cylindrical worm and a helical gear offers improved torque transmission and kinematically favorable sliding characteristics. This results in smooth and efficient movement of a driven actuator and a higher efficiency than the prior art comfort drive with a worm gear stage. Efficiency losses due to friction and wear are minimized. Moreover, the adjustment and comfort drive according to the invention is quiet. In addition, the adjustment and comfort drive according to the invention is characterized by its flexibility and adaptability to various applications.
[0016] The adjustment and comfort drive according to the invention can be used in particular in the following devices: headlight adjustment, especially for aligning the light cone; in air conditioning systems for regulating the temperature and airflow in the interior; in electric window regulators for opening and closing the side windows, for driving window shading devices; in electric tailgates for opening and closing and as a closing aid; in door locking for unlocking and locking; in sliding doors for opening and closing; in seat adjustment for adjusting the backrest area, for adjusting the seat tilt, longitudinal adjustment and depth adjustment as well as in a massage function; in engine management, especially in the flap control for air and exhaust gas and in the valve control for cooling applications; in the rear spoiler adjustment; in the folding in and out of a trailer hitch.for opening and closing the sunroof or panoramic roof, for the electric brake booster, for fine-tuning the chassis, for actuating valves, for example coolant valves, for the door drive, for the door closing assist, swivel locking function for the trailer hitch, for opening and closing charging flaps and for locking and unlocking charging plugs in electric vehicles.
[0017] According to an advantageous embodiment of the invention, the adjustable and comfort drive is equipped with a comfort drive base on which the worm and the face gear are rotatably mounted, at least indirectly. The comfort drive base can form a housing or housing part, or be connected to a housing. The comfort drive base serves as a structural element that securely and precisely positions the worm and the face gear, as well as any other mechanical components of the drive. The rotatable mounting of the worm and the face gear on the comfort drive base ensures low-friction and efficient transmission of the rotational movement. Furthermore, the rotatable mounting of the worm and the face gear on the comfort drive base ensures stable and durable operation of the drive, as it distributes mechanical loads evenly and minimizes vibrations.The comfort drive base can be manufactured from various materials, selected according to the application to meet specific requirements for load-bearing capacity, rigidity, weight, and temperature and humidity resistance. Integrating the worm gear and the face gear into a single comfort drive base simplifies the assembly of the adjustment and comfort drive, as the unit is mounted as a single assembly at the point of use. The installation of individual parts on the final product is avoided or at least reduced. The positioning of the components relative to each other is predetermined by the comfort drive base. This leads to reduced manufacturing costs and increased production speed. The comfort drive base can also be equipped with additional mounting points, enabling easy and secure integration of the drive into various vehicles.
[0018] According to a further advantageous embodiment of the invention, the worm gear is connected at a first end in a rotationally fixed manner to a motor shaft of a motor, to an output gear of one or more preceding gear stages, or to a manually driven shaft, such that the torque of the motor or the manually driven shaft is transmitted to the worm gear. The worm gear can also be rotatably mounted in the motor or in a motor housing of the motor. One or more gear stages can also be arranged between the motor and the worm gear. These can be referred to as upstream gear stages.
[0019] According to a further advantageous embodiment of the invention, a second end of the worm, opposite the first end, is a free end. The worm is designed as a shaft equipped with at least one thread. The single-sided bearing ensures that the worm is held stably and precisely in its position, guaranteeing reliable transmission of the rotational motion to the face gear. The single-sided bearing of the worm simplifies the drive design, as fewer bearing components are required, leading to a reduction in manufacturing costs and a simplification of the assembly process. Furthermore, the single-sided bearing of the worm can reduce the space requirement, which is particularly important in the automotive sector, where available space is often limited.Furthermore, the one-sided mounting of the screw can contribute to improved ease of maintenance, as it facilitates access to the screw and its bearing components.
[0020] According to a further advantageous embodiment of the invention, a second end of the worm, opposite the first end, is rotatably mounted, for example, on the comfort drive base. This mounting of the worm ensures that resulting gear forces, particularly radial forces, are absorbed, that the worm deflects less under the influence of these forces, and that bending fracture of the worm is thus avoided. Furthermore, the two-sided mounting of the worm enables more stable and uniform rotation around the geometric axis of the worm, leading to a reduction in vibrations and noise during operation. The additional mounting also contributes to the longevity of the components by reducing wear on the worm and the bearings. This is particularly important in applications where the drive is operated frequently and under varying loads.The even distribution of forces across the bearings prevents uneven loading, which extends the service life of the bearings and the worm gear. According to a further advantageous embodiment of the invention, the toothing of the face gear has an elliptically rounded tooth root. This means that the base of the face gear teeth has an elliptical shape, resulting in a rounding. This reduces stresses in the tooth root. This, in turn, increases the load-bearing capacity and reduces the risk of tooth breakage.
[0021] According to a further advantageous embodiment of the invention, the toothing of the face gear features a chamfered tooth tip. This means that the edges of the teeth are chamfered in the tip region. This reduces the risk of edge bearing and thus the risk of local stress concentrations, which increases the service life and reliability of the face gear. By avoiding local stress concentrations, the probability of a reduction in load-carrying capacity is reduced, which is particularly important in applications with high loads and torques.
[0022] Furthermore, chamfering the end face improves the running characteristics and smoothness of the face gear, leading to a reduction in vibration and noise during operation. Additionally, chamfering the end face can facilitate assembly and installation of the face gear, as the chamfered edges are less susceptible to damage during handling.
[0023] According to a further advantageous embodiment of the invention, the toothing of the face gear has a continuous run-out on one or both sides without tooth face edges. The absence of tooth face edges means that the teeth do not extend to the outer or inner circumferential side of the face gear. With a continuous run-out on both sides, the teeth do not extend to either the outer or inner circumferential side of the face gear. With a continuous run-out on one side, the teeth extend to the inner circumferential side but not to the outer circumferential side, or vice versa. Due to the lateral connection of the tooth, it is more stable with respect to the forces acting upon it. Local stress concentrations at the tooth face edges are avoided, thus increasing the load-bearing capacity against tooth face edge breakage on the gear. Furthermore, the load-bearing capacity of the worm gear is increased in the area where tooth face edges are avoided.Furthermore, the lubricating film is improved by avoiding a lubricating wedge forming the tooth face edge. In this case, the worm must be designed and positioned relative to the face gear such that the engagement of the worm with its at least one turn in the face gear's teeth is located within the area of the face gear's fully formed tooth profiles. Preferably, the worm's thread and the face gear's teeth are in effective engagement at at least three contact points. Outside of the fully formed tooth profiles, a collision between the worm and the face gear must be avoided.
[0024] According to a further advantageous embodiment of the invention, each tooth of the helical gear of the face gear has a convex and a concave tooth flank. This improves the engagement of the worm gear and results in better force distribution during engagement. As an additional measure, the pressure angle on the convex tooth flank can be smaller than on the concave tooth flank. This further improves the load-bearing capacity and efficiency.
[0025] According to a further advantageous embodiment of the invention, the width of each tooth of the face gear decreases from an inner tooth end, which faces the geometric axis of the face gear, to an outer tooth end facing away from the inner tooth end. This tooth shape is also referred to as a comma-shaped tooth head. It improves the engagement of the worm gear with the face gear and ensures better force distribution during engagement.
[0026] According to a further advantageous embodiment of the invention, the thread of the worm engages with the teeth of the face gear at at least three contact points. If the worm has multiple threads, these threads engage with the teeth of the face gear at a total of at least three contact points.
[0027] According to a further advantageous embodiment of the invention, the thread in a worm shaft of the worm forms a profiled groove with a helical path and extends, with respect to the geometric axis of the worm, from a first thread end to a second thread end. At least at the first thread end, the thread has a radial run-out, with respect to the geometric axis of the worm, into a threadless section of the worm shaft. The run-out is also aligned with the helix angle.
[0028] According to a further advantageous embodiment of the invention, the comfort drive has at least one further gear stage connected to the face gear, which couples to the face gear on the output side. Advantageously, the combination of the worm and the face gear according to the invention forms a first gear stage that connects directly to a motor or a manual drive, wherein the worm is coupled to a motor shaft of the motor or to a shaft of the manual drive. In this case, the gear stage connected to the face gear forms a second gear stage, which is driven by the face gear. The second gear stage can also comprise a combination of a worm and a face gear according to the invention or other types of gears, for example, a spur gear set, a planetary gear set, or a screw drive.The additional gear stage can, for example, change the gear ratio, convert a rotational motion into a linear motion, or redirect the torque. According to a further advantageous embodiment of the invention, the face gear is coupled, at least indirectly, to an output shaft of the comfort drive in such a way that it transmits a torque to this output shaft.
[0029] According to a further advantageous embodiment of the invention, the comfort drive comprises a linear drive with a threaded spindle and a spindle nut engaged with the threaded spindle. This combination enables a precise and stable conversion of the rotational motion into a linear motion.
[0030] According to a further advantageous embodiment of the invention, the threaded spindle is rotatably mounted on the comfort drive base and connected to the face gear in a twist-resistant manner, while the spindle nut is mounted on the comfort drive base in a twist-resistant and linearly displaceable manner. The rotatable mounting of the threaded spindle on the base ensures that the spindle can rotate freely while simultaneously being rigidly connected to the face gear to guarantee synchronous movement. The spindle nut is mounted on the comfort drive base in a linearly displaceable manner and secured against rotation, thus enabling smooth and controlled linear movement. This arrangement offers high precision and stability of the movement, high efficiency of the drive mechanism, and a reduction in wear and maintenance requirements.
[0031] According to a further advantageous embodiment of the invention, the spindle nut is arranged in a rotational manner on the face gear or is part of the face gear, while the threaded spindle is mounted in a rotational and linearly displaceable manner on the comfort drive base. The spindle nut is thus either rigidly connected to the face gear or an integral part thereof. This combination of face gear and spindle nut ensures that the rotary motion of the face gear is transmitted directly and without backlash to the spindle nut. This results in a precise and efficient transmission of the rotary motion to the linear motion of the threaded spindle.
[0032] According to a further advantageous embodiment of the invention, the face gear is simultaneously designed as a spindle nut. This means that the face gear not only fulfills the function of a gear that is set in rotation by the worm gear, but also assumes the function of a spindle nut that runs on a threaded spindle. While the helical teeth are located on the face of the face gear, a central through-hole, which runs coaxially to the geometric axis of the face gear, can be equipped as a threaded bore that performs the function of the spindle nut. The threaded spindle is guided in this threaded bore. The threaded spindle engages with the thread of the threaded bore of the face gear.The dual functionality of the face gear as a spindle nut reduces the number of components required, simplifying the design and lowering manufacturing costs. Furthermore, the drive unit's footprint is reduced because two functions are integrated into a single component. This is particularly advantageous in the automotive sector, where available space is often limited.
[0033] According to a further advantageous embodiment of the invention, the adjustment and comfort drive comprises a linear drive with a rack and a linear drive gear meshing with the rack. The rack is an elongated component that can be moved along a linear geometric axis, while the linear drive gear is a rotating component that engages with the rack and enables its linear movement. The linear drive gear is driven either directly or indirectly by the face gear. For this purpose, the linear drive gear can, for example, be arranged at a rotational angle to the face gear or be formed integrally with the face gear. The interaction between the rack and the linear drive gear is achieved through gearing, in which the teeth of the linear drive gear engage with the teeth of the rack, thus ensuring low-friction and efficient power transmission.
[0034] According to a further advantageous embodiment of the invention, the linear drive gear is twisted and connected to the face gear.
[0035] According to a further advantageous embodiment of the invention, the linear drive gear is integrally formed with the face gear. It advantageously forms an integral part of the face gear.
[0036] According to a further advantageous embodiment of the invention, the linear drive gear and the face gear are arranged on a common shaft. The common shaft optimizes the mechanical connection between the linear drive gear and the face gear.
[0037] According to a further advantageous embodiment of the invention, the worm and / or the face gear are made of plastic. This material has the advantage of being lightweight. Furthermore, the components can be manufactured cost-effectively in large quantities. Plastic also exhibits high corrosion resistance, which increases the durability and reliability of the components, particularly in humid or corrosive environments. Another advantage of plastic is its noise-dampening property. By using plastic for the worm and / or the face gear, the operating noise of the drive is reduced. In addition, plastic offers a good balance between strength and flexibility. Shocks and vibrations can be absorbed.
[0038] According to a further advantageous embodiment of the invention, the worm and / or the face gear are made of a thermoplastic or thermoset material. Besides the advantages in manufacturing, the material of the worm and the face gear influences the friction properties between the worm and the face gear. These, in turn, affect the efficiency and service life of the drive.
[0039] According to a further advantageous embodiment of the invention, the worm and / or the face gear are manufactured by plastic injection molding. This represents a cost-effective manufacturing process, particularly for large production runs, with which complex geometries can be produced with high precision and repeatability.
[0040] According to a further advantageous embodiment of the invention, the face gear is manufactured by hot stamping. In this manufacturing process, the material of the face gear is shaped under the influence of heat and pressure. This method enables precise and uniform shaping of the helical teeth on the face of the gear.
[0041] In a further advantageous embodiment, the helical gear is manufactured by injection molding and comprises a metallic or ceramic insert, or a plastic insert. Metallic inserts offer high strength and wear resistance, while ceramic inserts exhibit high temperature resistance and hardness. A plastic insert can be designed with or without reinforcement, for example, fiber reinforcement. A fiber-reinforced plastic insert combines the advantages of lightweight construction and increased strength through the embedding of fibers, such as glass or carbon fibers, in the plastic matrix. These inserts improve the structural integrity of the helical gear and contribute to the reduction of deformation and material fatigue.The integration of such inserts into the face gear leads to improved performance and durability of the comfort drive, particularly under the demanding operating conditions in the automotive sector. According to a further advantageous embodiment of the invention, the face gear consists of a metallic or ceramic material and is sintered, at least in the area of the teeth. Metallic materials offer high strength and durability, which is particularly important to withstand the mechanical stresses that can occur in the automotive sector. Ceramic materials, on the other hand, are characterized by their high wear resistance and temperature resistance, which is particularly advantageous in applications where high temperatures and friction occur.Sintering in the gear teeth area further improves the material properties by creating a denser and more homogeneous structure, which increases the service life and reliability of the face gear. Sintering also increases the surface hardness in the gear teeth area, improving wear resistance and the ability to withstand high loads. This results in a longer service life for the face gear and reduces the need for maintenance and replacement.
[0042] According to a further advantageous embodiment of the invention, the at least partially sintered face gear is impregnated with a lubricant, a plastic, or a metallic impregnating agent. Impregnating the face gear with a lubricant such as oil provides the following properties: (emergency) lubrication, as the lubricant-filled pores act as a lubricant reservoir. This also increases wear resistance and provides a degree of corrosion protection. Impregnation with plastics such as resins or wax can close the pores in the material, thus achieving a seal or a degree of corrosion protection. Furthermore, impregnation with plastics is a fundamental requirement as a pretreatment for further coating processes such as electroplating.Impregnation with metallic impregnating agents, usually with low-melting alloys, can be used to densify the face gear or to increase the mechanical strength of the face gear.
[0043] According to a further advantageous embodiment of the invention, the face gear consists of a metallic material and is manufactured by means of cold extrusion.
[0044] According to a further advantageous embodiment of the invention, the face gear consists of a metallic material and is manufactured by forging.
[0045] According to a further advantageous embodiment of the invention, the face gear is at least partially manufactured by machining.
[0046] According to a further advantageous embodiment, the adjustment and comfort drive is equipped with grease or oil lubrication.
[0047] Further advantages and advantageous embodiments of the invention can be seen in the following description, the drawing and the claims.
[0048] drawing
[0049] The drawing shows exemplary embodiments of the invention. It shows:
[0050] Figure 1 shows a first embodiment of an adjustment and comfort drive in a top view. Figure 2 shows the adjustment and comfort drive according to Figure 1 in a sectional view with a section along the plane marked A - A in Figure 1.
[0051] Figure 3 is a section of Figure 2 concerning the area marked B in Figure 2.
[0052] Figure 4 Adjustment and comfort drive according to Figure 1 in perspective view,
[0053] Figure 5 Worm and part of the face gear of the adjustment and comfort drive according to Figure 1 ,
[0054] Figure 6 shows a second embodiment of an adjustment and comfort drive in a top view.
[0055] Figure 7 Adjustment and comfort drive according to Figure 6 in perspective view,
[0056] Figure 8 shows a second embodiment of a face gear.
[0057] Figure 9 shows a third embodiment of an adjustment and comfort drive in a top view.
[0058] Figure 10 Adjustment and comfort drive according to Figure 9 in sectional view with section along the plane marked D - D,
[0059] Figure 11 Adjustment and comfort drive according to Figure 9 in perspective view,
[0060] Figure 12 Adjustment and comfort drive according to Figure 9 in perspective view, rotated relative to the representation in Figure 11, Figure 13 Adjustment and comfort drive according to Figure 9 in sectional view with section along the plane marked E - E,
[0061] Figure 14 shows a third embodiment of a face gear in a perspective view from above.
[0062] Figure 15 Planar gear according to Figure 14 in a top view,
[0063] Figure 16 Excerpt from the illustration according to Figure 15,
[0064] Figure 17 Section through the face gear according to Figure 14 along the plane A-A,
[0065] Figure 18 shows the fourth embodiment of a face gear in a perspective view from above.
[0066] Figure 19 shows the fifth embodiment of a face gear in a perspective view from above.
[0067] Figure 20 shows the sixth embodiment of a face gear in a top view.
[0068] Figure 21 Planar gear according to Figure 20 in a sectional view with a section along the plane marked A - A in Figure 20,
[0069] Figure 22 Planar gear according to Figure 20 in perspective view from above,
[0070] Figure 23 fourth embodiment of an adjustment and comfort drive in a top view, Figure 24 adjustment and comfort drive according to Figure 23 in sectional view with section along the plane marked C - C,
[0071] Figure 25 Adjustment and comfort drive according to Figure 23 in perspective view,
[0072] Figure 26 shows the fifth embodiment of an adjustment and comfort drive in perspective view.
[0073] Figure 27 Adjustment and comfort drive according to Figure 26 with comfort drive base,
[0074] Figure 28 shows a sixth embodiment of an adjustment and comfort drive in perspective view.
[0075] Figure 29 Adjustment and comfort drive according to Figure 28 in sectional view,
[0076] Figure 30 Adjustment and comfort drive according to Figure 28 with comfort drive base,
[0077] Figure 31 Planar gear of the adjustment and comfort drive according to Figure 28,
[0078] Figure 32 seventh embodiment of an adjustment and comfort drive in perspective view,
[0079] Figure 33 Adjustment and comfort drive according to Figure 32 with comfort drive base,
[0080] Figure 34 Adjustment and comfort drive according to Figures 32 and 33 in a top view, Figure 35 Adjustment and comfort drive according to Figure 33 in sectional view, section along the plane marked A - A in Figure 34,
[0081] Figure 36 Adjustment and comfort drive according to Figure 33 in side view,
[0082] Figure 37 Adjustment and comfort drive according to Figure 33 in sectional view,
[0083] Section along the plane marked B - B in Figure 36,
[0084] Figure 38 Adjustment and comfort drive according to Figure 33 in sectional view,
[0085] Section along the plane marked C - C in Figure 36,
[0086] Figure 39 Planar gear of the adjustment and comfort drive according to Figures 33 to 38.
[0087] Description of the exemplary implementations
[0088] Figures 1 to 5 show a first embodiment of an adjustment and comfort drive 1 for actuators in the automotive sector. The adjustment and comfort drive 1 comprises a cylindrical worm 2, which is driven to rotate about a geometric worm axis 3 by a motor 12 shown in Figure 4. For this purpose, a motor shaft of the motor 12 (not shown in the drawing) is connected to a worm shaft 9 of the worm 2. The worm 2 has a thread 4 with a constant pitch on its circumferential surface. The adjustment and comfort drive also includes a face gear 5, which has a helical tooth 7 on one face 6. This tooth 7 is located on the outer edge of the face gear 5. The worm 2 is in operative engagement with the face gear 5, with the thread 4 of the worm 2 engaging in the tooth 7 of the face gear 5.This causes the face gear 5 to rotate about a geometric face gear axis 8. The geometric worm axis 3 and the geometric face gear axis 8 are skew geometric lines whose distance d is smaller than the outer radius R of the face gear 5. The distance d and the radius R are shown in Figure 1. The illustration clearly shows that the distance d is smaller than the radius R.
[0089] Figure 2 shows a section along the plane labeled AA in Figure 1. Figure 3 shows a detail from Figure 2. In these views according to Figures 2 and 3, it can be seen that the thread 4 of the worm 2 engages with the helical teeth 7 of the face gear 5, thereby rotating the face gear 5 about the face gear axis 8. The face 6 of the face gear 5, with the helical teeth 7 meshing with the thread 4 of the worm 2, is also visible.
[0090] Figure 3 shows that the teeth of the face gear 5 have an elliptically rounded tooth root shape. Furthermore, it can be seen in Figure 3 that the teeth of the face gear 5 have a tip chamfer, which reduces the mechanical stress on the tooth tips. The teeth of the face gear 5 have specific tooth flank angles α. a and up, which define the contact geometry between the worm 2 and the face gear 5.
[0091] Figure 4 shows the first embodiment of an adjustment and comfort drive 1 with a motor 12 and a shaft 13 on which the face gear 5 is arranged. The shaft 13 serves as an output shaft via which the torque from the face gear 5 can be transmitted to a component not shown in the drawing.
[0092] Figure 5 shows the design of the helical toothing of the face gear 5 and the worm 2. Each tooth of the toothing has a convex tooth flank 10 and a concave tooth flank 11. The pressure angle of the worm 2 and face gear 5 is smaller at the convex tooth flank 10 than at the concave tooth flank 11. This results in a distribution of the forces over the tooth flanks 10 and 11.
[0093] In the first embodiment according to Figures 1 to 5, the worm 2 is connected at one end to the motor 12, so that the torque of the motor 12 is transmitted to the worm 2. For this purpose, the worm shaft 9 is non-rotatably connected to a motor shaft (not shown). The other end of the worm 2, opposite the motor 12, is free. It is not additionally supported.
[0094] Instead of directly connecting the worm shaft 9 to a motor shaft of the motor 12, a threaded stage 14 can be provided upstream of the worm 2 between the motor 12 and the worm 2. A corresponding second embodiment is shown in Figures 6 and 7. The upstream gear stage 14 comprises an input gear 15, which is coupled via a shaft 16 to a motor (not shown) or to another upstream gear stage (not shown). The input gear 15 meshes with an output gear 17. This, in turn, is rotationally fixed to the worm 2. For this purpose, the output gear 17 is coupled to the worm shaft 9. The upstream gear stage 14 serves to adjust the gear ratio between a motor and the worm 2.
[0095] Figure 8 shows a second embodiment of a face gear 18. This embodiment differs from the first embodiment of a face gear 5 according to Figures 1 to 5 in that, in the second embodiment, the teeth 19 have a shape referred to as a comma head. The width of each tooth 19 is greater at its inner end 19a, which faces the geometric face gear axis 8, than at its outer end 19b, which faces away from the inner end 19a and the geometric face gear axis 8. The width of each tooth 19 thus decreases from the inside out. Figures 9 to 13 show a third embodiment of an adjustment and comfort drive 20. The motor 12 and the face gear 5 with geometric face gear axis 8 are identical to those of the first embodiment of an adjustment and comfort drive 1 according to Figures 1 to 5.Therefore, the same reference numerals are given for these corresponding components in Figures 9 to 13. However, the worm 22 of the adjustment and comfort drive 20 differs from the worm 2 of the adjustment and comfort drive 1. Unlike the worm 2, the worm 22 is rotatably mounted at its end facing away from the motor 12 in a bearing 28. This bearing 28 is arranged in a bearing receptacle 27, which is part of a comfort drive base 24. The bearing 28 is shown in Figure 13. The motor housing 12 and the face gear 5 are mounted on the comfort drive base 24. The worm 22 is driven by the motor located in the motor housing 12 to rotate about the geometric worm axis 23. The illustration in Figure 12 shows that the comfort drive base 24 is closed by a cover 25. Furthermore, in Figure 12 an output shaft 26 can be seen, which protrudes from the comfort drive base 24.It is connected to the face gear 5. A component not shown in the drawing can be coupled to the output shaft, which is to be moved by the adjustment and comfort drive 20.
[0096] Figures 10 to 18 show various embodiments of a face gear.
[0097] The third embodiment of a face gear 35, shown in Figures 14 to 17, has a helical toothing 37 on its face 36 with continuous run-out on both sides and no tooth edges. The face gear 35 has the outer shape of a cylindrical disk with a central through-hole 41. The central through-hole 41 serves to accommodate a shaft (not shown in Figures 14 to 17) or other connecting element that supports the rotary motion of the face gear 35 and may optionally serve as an output shaft. The helical toothing 37 is located on the face 36, which, in terms of the geometric shape of the face gear, forms a cap of the cylinder. The toothing 37 is formed by recesses on the face 36. These recesses extend radially in a helical pattern. However, they do not extend to the central through-hole or to an outer circumferential side of the face gear 35.Therefore, there are no tooth end edges at either the through-opening or the circumferential side. Instead, each of the recesses is equipped with an inner outlet 38 near the central through-opening 41 and an outer outlet 39 near the circumferential side of the face gear 35. The depth of the recesses decreases continuously at the inner outlet 38 and the outer outlet 39. This is particularly evident in the sectional view according to Figure 17.
[0098] Figure 16 shows the engagement area 40 of a worm gear (not shown). The illustration shows that the engagement area is located within the fully formed tooth profile between the inner outlet 38 and the outer outlet 39.
[0099] Figure 18 shows a fourth embodiment of a face gear 45. This differs from the face gear 35 shown in Figure 14 in that the face gear 45 has a toothing with an outer runout 49, while the recesses extend to the central through-hole, so that tooth face edges are formed there.
[0100] Figure 19 shows a fifth embodiment of a face gear 55. This differs from the face gear 35 shown in Figure 10 in that the face gear 55 has a tooth profile with an inner runout 58, while the recesses extend outwards to the circumferential side, so that tooth face edges are formed there. Figures 20 to 22 show a sixth embodiment of a face gear 65. Like the preceding embodiments, the face gear 65 has a through-hole 71 centrally located with respect to the geometric axis 68 of the face gear. The face gear 65 includes an insert 69, which is placed in an injection mold (not shown in the drawing) during manufacturing by injection molding. The insert 69 consists of a first material, for example, metal or ceramic.In area 70 of the helical gear 67 on the face 66, the insert 69 is overmolded with plastic. The face gear 65 can also be manufactured by multi-component injection molding. In this case, the insert 69 consists of a first component and area 70 of a second component.
[0101] Figures 23 to 25 show a fourth embodiment of an adjustment and comfort drive 100. The drive comprises a comfort drive base 114, on which a motor with motor housing 12, a cylindrical worm 22, and a face gear 105 are mounted. The motor with motor housing 12, the worm 22, and the bearing 27 correspond essentially to the third embodiment shown in Figures 9 to 13, and are therefore provided with the same reference numerals. The worm is driven by the motor, which is arranged in the motor housing 12, to rotate about a geometric worm axis 23. At the end opposite the motor, the worm 22 is rotatably mounted on the bearing 27. The bearing receptacle 27 is arranged on the comfort drive base 114.The face gear 105 is provided with a spiral toothing on one face side and is in effective engagement with the worm 22, so that the worm 22 meshes with its thread in the toothing of the face gear 105 and drives it to rotation about a geometric face gear axis 108.
[0102] In contrast to the third embodiment shown in Figures 9 to 13, the adjustment and comfort drive 100 is equipped with a second gear stage in addition to the first gear stage, which comprises the worm gear 22 and the face gear 105. This second gear stage has a first gear 109 with spur teeth and a second gear 110 with spur teeth. The first gear 109 with spur teeth is either rotationally fixed to the face gear 105 or is formed from a single piece with the face gear 105. This is particularly evident in Figure 24. The torque of the face gear 105 is thus transmitted to the first gear 109, whereby the first gear 109 rotates together with the face gear 105 about the geometric axis 108 of the face gear. The second gear 110 meshes with its face teeth in the face teeth of the first gear 109.The torque is transmitted to the second gear 110, which is driven to rotate about a geometric gear axis 111. The geometric gear axis 108, common to the face gear 105 and the first gear 109, and the geometric gear axis are parallel to each other. They are spaced apart, a distance which is denoted by M in Figures 23 and 24. The second gear 110 is connected to an output shaft 116, which protrudes from the comfort drive base 114. The comfort drive base 114 is fitted with a cover 115. The comfort drive base and the cover form a closed housing that protects the transmission from external influences.
[0103] Figures 26 and 27 show a fifth embodiment of an adjustment and comfort drive 120. The drive 120 comprises a motor 29 that drives a worm gear 122 to rotate. The worm gear 122 is in operative engagement with a face gear 125, which is driven to rotate about the face gear axis 128 by the motor 129 and the worm gear 122. In this respect, the fifth embodiment 120 corresponds to the first embodiment 1 of an adjustment and comfort drive. In contrast to the first embodiment, the adjustment and comfort drive 120 is equipped with an additional gear stage. This is a spindle drive that converts the rotational motion of the motor 129, the worm gear 122, and the face gear 125 into a linear motion.The spindle drive comprises a threaded spindle 130, which is rotationally fixed to the face gear 125, so that the rotation of the face gear 125 is transmitted to the threaded spindle 130, causing it to rotate about the geometric axis 128 of the face gear. A spindle nut 131 is engaged with the threaded spindle 130. The spindle nut 131 is mounted to a drive base or other component with rotational resistance and is linearly movable. Rotation of the threaded spindle 130 therefore results in a linear movement of the spindle nut 131 in the direction of the geometric axis 128 of the face gear.
[0104] Figure 27 shows the comfort drive base 134, which surrounds the worm 122 and the face gear 125. The mounting of the threaded spindle 131 on the comfort drive base is not shown in the drawing.
[0105] Figures 28 to 31 show a sixth embodiment of an adjustment and comfort drive 140. The drive 140 comprises a motor with a motor housing 12, the motor driving a worm gear 22 to rotation. The worm gear 22 is rotatably mounted at its end furthest from the motor on a comfort drive base 144. The worm gear 22 engages with a face gear 145, which is driven to rotation about the face gear axis 148 by the motor and the worm gear 22.
[0106] In this respect, the sixth embodiment 140 corresponds to the third embodiment 20 of an adjustment and comfort drive. In contrast to the third embodiment, the adjustment and comfort drive 140 is equipped with an additional gear stage. This is a spindle drive that converts the rotational motion of the motor, the worm 22, and the face gear 145 into a linear motion. Unlike the spindle drive of the fifth embodiment according to Figures 26 and 27, the face gear 145 is also designed as a spindle nut, so that the spindle nut is driven to rotate. For this purpose, the face gear 145 has a through-hole 151. In the area of the through-hole 151, the face gear 145 is equipped with an internal thread 152. A threaded spindle 150 engages with this internal thread 152. This spindle is mounted on the comfort drive base in a rotationally fixed and linearly movable manner.Rotation of the face gear 145 about the geometric face gear axis 148 thus results in a linear movement of the threaded spindle 150 along the geometric face gear axis 148. Figure 31 shows the face gear 145 in isolation. The illustration shows that the face gear 145 has teeth 147 on its face 146. With the exception of the through-hole 151 with internal thread 152, the face gear 145 is identical to the face gear 65 shown in Figures 16 to 18.
[0107] Figures 32 to 39 show a sixth embodiment of an adjustment and comfort drive 160. The drive 160 comprises a motor 169 with a motor housing 172, wherein the motor 169 drives a worm 162 to rotate about a geometric worm axis 163. The worm 162 is not additionally rotatably mounted at its end facing away from the motor. It is in operative engagement with a face gear 165, which is equipped with a helical tooth 167 on its face 166. The face gear 165 is driven to rotate about the face gear axis 168 by the motor 169 and the worm 162. In this respect, the sixth embodiment 160 corresponds to the first embodiment 1 of an adjustment and comfort drive.Just like the fourth and fifth embodiments, the sixth embodiment of an adjustment and comfort drive 160 has a further gear stage that converts the rotational motion of the motor, the worm gear, and the face gear into a linear motion. However, this is not a spindle drive, but rather a combination of a spur gear 170 and a rack 171. The gear 170 is rotationally fixed to the face gear 165, so that the rotation of the face gear 165 about the geometric axis 168 of the face gear is transmitted to the gear 170. The gear 170 is in operative engagement with the rack 171, so that the rotation of the gear 170 is transmitted into a linear motion of the rack 171 along the geometric linear axis 176. Figure 35 shows that the geometric linear axis 176 of the rack 171 is parallel to the geometric worm axis 163 of the worm 162.The geometric plane gear axis 168 runs perpendicular to these two axes without intersecting them. The geometric plane gear axis 168 is a straight line skew to the geometric worm axis 163 and the geometric linear axis 176.
[0108] The worm gear 162, the face gear 165, the gear 170 and partly also the rack 171 are housed in a comfort drive base 174. This is closed by a cover 175.
[0109] All features of the invention can be essential to the invention, both individually and in any combination. Reference numerals
[0110] 1 Adjustment and comfort drive
[0111] 2 snails
[0112] 3 Geometric worm axis
[0113] 4 threads
[0114] 5 Planar gear
[0115] 6 Plan page
[0116] 7 Spiral toothing
[0117] 8 Geometric face gear axis
[0118] 9 worm shaft
[0119] 10 Convex flank of the face gear teeth
[0120] 11 Concave flank of the face gear teeth
[0121] 12 engine
[0122] 13th wave
[0123] 14 Upstream gear stage
[0124] 15 Drive-side gear of the upstream gear stage 16 Shaft
[0125] 17 Output-side gear of the upstream gear stage 18 Face gear
[0126] 19 teeth
[0127] 19a inner tooth end
[0128] 19b outer end of tooth
[0129] 20 Adjustment and comfort drive
[0130] 22 snail
[0131] 23 Geometric worm axis
[0132] 24 Comfort drive base
[0133] 25 lids
[0134] 26 Output shaft
[0135] 27 Bearing intake
[0136] 28 bearings for worm gear
[0137] 35 Plane gear 36 Plan side
[0138] 37 Spiral toothing
[0139] 38 outlet inside
[0140] 39 outlet outside
[0141] 40 Intervention area of the snail
[0142] 41 Passage opening
[0143] 45 Face gear
[0144] 49 outlet outside
[0145] 55 Face gear
[0146] 58 outlet inside
[0147] 65 Face gear
[0148] 66 Plan page
[0149] 67 spiral teeth
[0150] 68 geometric face gear axle
[0151] 69 inserts made from a first material
[0152] 70 Overmolded area made of a second material 71 Through opening
[0153] 100 adjustable and comfort drive
[0154] 105 Face gear
[0155] 108 geometric plane gear axle
[0156] 109 Gear with face teeth
[0157] 110 Gear with face teeth
[0158] 111 geometric gear axis
[0159] 114 Comfort drive base
[0160] 115 lids
[0161] 116 Output shaft
[0162] 120 Adjustment and comfort drive
[0163] 122 snail
[0164] 125 face gear
[0165] 128 geometric face gear axle
[0166] 129 Engine
[0167] 130 Spindle Spindle nut
[0168] Comfort drive base
[0169] Adjustable and comfort drive Comfort drive base
[0170] face gear
[0171] Plan page
[0172] spiral toothing
[0173] geometric plane gear axis spindle
[0174] Passage opening
[0175] internal thread
[0176] Adjustable and comfort drive
[0177] Snail
[0178] geometric worm shaft face gear
[0179] Plan page
[0180] spiral toothing
[0181] geometric plane gear axis
[0182] Motor
[0183] Gear with spur teeth, rack
[0184] engine housing
[0185] Wave
[0186] Comfort drive base
[0187] Lid
[0188] geometric linear axis of the rack
Claims
1. Attorney's file: 524011 -PCT Applicant: Framo Morat GmbH & Co KG Franz-Morat-Straße 6 79871 Eisenbach Title: Adjustment and comfort drive for actuators in the automotive sector REQUIREMENTS 1. Adjustment and comfort drive for actuators in the automotive sector with a cylindrical worm (2, 22, 122, 162) which is driven to rotation about a geometric worm axis (3, 23, 163) and which has at least one thread (4) on its circumferential surface, with a face gear (5, 35, 45, 55, 65, 105, 125, 145, 165) which has a helical toothing (7, 37, 167) on one face (6, 36, 146, 166), wherein the worm (2, 22, 122, 162) is in effective engagement with the face gear (5, 35, 45, 55, 65, 105, 125, 145, 165) such that the worm (2, 22, 122, 162) meshes with its at least one thread in the teeth of the face gear (5, 35, 45, 55, 65, 105, 125, 145, 165) and the worm (2, 22, 122, 162) thereby rotates the face gear (5, 35, 45, 55, 65, 105, 125, 145, 165) about a geometric face gear axis (8, 68, 108, 128, 148, 168) drives it to rotation, where the geometric worm axis (3, 23, 163) and the geometric face gear axis (8, 68, 108, 128, 148, 168) are skew geometric straight lines whose distance d is less than an outer radius R of the face gear (5, 35, 45, 55, 65, 105, 125, 145, 165).
2. Adjustment and comfort drive according to claim 1, characterized in that it is equipped with a comfort drive base (24, 114, 134, 144, 174) on which the worm gear (2, 22, 122, 162) and the face gear (5, 35, 45, 55, 65, 105, 125, 145, 165) are at least indirectly rotatably mounted.
3. Adjustment and comfort drive according to claim 1 or 2, characterized in that the worm gear (2, 22, 122, 162) is connected at a first end in a rotationally fixed manner to a motor shaft of a motor (9, 129) or to an output gear of one or more preceding gear stages or to a manually driven shaft.
4. Adjustment and comfort drive according to claim 3, characterized in that a second end of the worm (2, 122, 162) opposite the first end is a free end.
5. Adjustment and comfort drive according to claim 3, characterized in that a second end of the worm opposite the first end is rotatably mounted.
6. Adjustment and comfort drive according to one of the preceding claims, characterized in that the toothing (7, 37, 67, 167) of the face gear (5, 35, 45, 55, 65, 105, 125, 145, 165) has an elliptically rounded tooth root.
7. Adjustment and comfort drive according to one of the preceding claims, characterized in that the toothing (7, 37, 67, 167) of the face gear (5, 35, 105, 125, 145, 165) has a head edge fracture.
8. Adjustment and comfort drive according to one of the preceding claims, characterized in that the toothing (37) of the face gear (35, 45, 55) has a continuous run-out on one or both sides without tooth face edges.
9. Adjustment and comfort drive according to one of the preceding claims, characterized in that each tooth of the helical toothing (7) of the face gear (5) has a convex tooth flank (10) and a concave tooth flank (11).
10. Adjustment and comfort drive according to one of the preceding claims, characterized in that, for each tooth (19) of the helical gear (18), its width at the tooth head decreases from an inner tooth end (19a) which faces the geometric helical gear axis (8) to an outer tooth end (19b) facing away from the inner tooth end (19a).
11. Adjustment and comfort drive according to one of the preceding claims, characterized in that the thread (4) or threads of the worm (2, 22, 122, 162) are in effective engagement with the teeth (7, 37, 167) of the face gear (5, 35, 45, 55, 65, 105, 125, 145, 165) at at least three contact points.
12. Adjustment and comfort drive according to one of the preceding claims, characterized in that it has at least one further gear stage adjoining the face gear, which is coupled to the face gear (5, 35, 105, 125, 145, 165) on the output side.
13. Adjustment and comfort drive according to one of the preceding claims, characterized in that the face gear (5, 105) is coupled at least indirectly to an output shaft (26, 116) of the adjustment and comfort drive (20, 100) in such a way that it transmits a torque to this output shaft (26, 116).
14. Adjustment and comfort drive according to one of the preceding claims, characterized in that it comprises a linear drive with a threaded spindle (130, 150) and a spindle nut (131) engaged with the threaded spindle (130, 150).
15. Adjustment and comfort drive according to claim 14 insofar as it refers back to claim 2, characterized in that the threaded spindle is rotatably mounted on the comfort drive base (130) and is connected to the face gear (125) in a twisting manner, and that the spindle nut (131) is received on the comfort drive base (130) in a twisting and linearly displaceable manner.
16. Adjustment and comfort drive according to claim 14 insofar as it refers back to claim 2, characterized in that the spindle nut is arranged in a twisted manner on the face gear or is part of the face gear (145), and that the threaded spindle (150) is received in a twisted and linearly displaceable manner on the comfort drive base (144).
17. Adjustment and comfort drive according to claim 16 characterized in that the face gear (145) is also designed as a spindle nut.
18. Adjustment and comfort drive according to one of the preceding claims, characterized in that it has a linear drive with a rack (171) and with a linear drive gear (170) engaging with the rack (171).
19. Adjustment and comfort drive according to claim 18 characterized in that the linear drive gear (170) is connected to the face gear (165) in a twisted manner.
20. Adjustment and comfort drive according to claim 18 or 19, characterized in that the linear drive gear (170) and the face gear (165) are arranged on a common shaft (173).
21. Adjustment and comfort drive according to one of the preceding claims, characterized in that the worm gear (2, 22, 122, 162) and / or the face gear (5, 35, 45, 55, 65, 105, 125, 145, 165) are made of plastic.
22. Adjustment and comfort drive according to claim 21, characterized in that the worm (2, 22, 122, 162) and / or the face gear (5, 35, 45, 55, 65, 105, 125, 145, 165) are made of a thermoplastic or thermoset.
23. Adjustment and comfort drive according to claim 21 or 22, characterized in that the worm gear (2, 22, 122, 162) and / or the face gear (5, 35, 45, 55, 65, 105, 125, 145, 165) are manufactured by plastic injection molding.
24. Adjustment and comfort drive according to claim 21 or 22, characterized in that the face gear (5, 35, 45, 55, 65, 105, 125, 145, 165) is manufactured by hot stamping.
25. Adjustment and comfort drive according to one of the preceding claims, characterized in that the face gear (65) is manufactured by injection molding and comprises a metallic or ceramic insert (69) or a plastic insert.
26. Adjustment and comfort drive according to one of claims 1 to 20, characterized in that the face gear (5, 35, 45, 55, 65, 105, 125, 145, 165) is made of a metallic or ceramic material and is sintered at least in the area of the toothing.
27. Adjustment and comfort drive according to claim 26, characterized in that the face gear (5, 35, 45, 55, 65, 105, 125, 145, 165) is impregnated with a lubricant or a plastic or a metallic impregnating agent.
28. Adjustment and comfort drive according to one of claims 1 to 20, characterized in that the face gear (5, 35, 45, 55, 65, 105, 125, 145, 165) is made of a metallic material and is manufactured by investment casting.
29. Adjustment and comfort drive according to one of claims 1 to 20, characterized in that the face gear (5, 35, 45, 55, 65, 105, 125, 145, 165) is made of a metallic material and is manufactured by means of cold extrusion.
30. Adjustment and comfort drive according to one of claims 1 to 20, characterized in that the face gear (5, 35, 45, 55, 65, 105, 125, 145, 165) is made of a metallic material and is produced by forging.
31. Adjustment and comfort drive according to one of the preceding claims, characterized in that the face gear (5, 35, 45, 55, 65, 105, 125, 145, 165) is at least partially manufactured by machining.
32. Adjustment and comfort drive according to one of the preceding claims, characterized in that it is equipped with grease or oil lubrication.