Arrangement for operating a vehicle clutch

Abstract

Arrangement for actuating a vehicle clutch, in which a movement of a pedal (1) mounted pivotably about an axis (A) of a pedal block is transferable to a kinematics having at least one energy store (3), by means of which an actuating force to be applied to the pedal (1) can be influenced, characterized in that the kinematics has a gear transmission which is operatively connected to the pedal (1) and is formed from non-circular gears / gear segments (4, 5), characterized in that the gears / gear segments (4, 5) are arranged at least partially on the pedal (1).

Description

[0001] The invention relates to an arrangement for actuating a vehicle clutch, in which a movement of a pedal pivotably mounted about an axis of a pedal bracket is transferable to a kinematics having at least one energy storage device, by means of which an actuating force to be applied to the pedal can be influenced, and in which the kinematics has a gear transmission which is operatively connected to the pedal and which is formed from non-circular gears / gear segments.

[0002] Known actuating devices for clutch or brake systems in motor vehicles feature spring assistance, the purpose of which is to reduce the actuating force applied by the driver to the pedal lever when operating the clutch. Especially at high drive power levels, high contact pressures are required at the clutch. This requires a high actuating force at the beginning of the pedal travel. After a maximum actuating force, the actuating force decreases until the end of the pedal travel.

[0003] To support the driver's operating force when engaging and disengaging the clutch, an over-center spring is typically provided on the pedal lever. This spring holds the unactuated pedal in its rest position and is initially slightly preloaded when the pedal moves between the (engaged) rest position and the (disengaged) end position. After overcoming the dead center, the spring supports further movement of the pedal by applying an additional force toward the fully depressed position. Before the dead center, however, the over-center spring exerts a force directed toward the pedal's rest position.

[0004] The disadvantage of this type of clutch assistance is the fact that when over-center springs are used, the force to be applied by the driver increases in the first part of the clutch pedal travel due to the design, thus resulting in an unfavorable force-travel characteristic curve for the clutch progression (sinusoidal curve).

[0005] While the over-center springs used in the current technology can store both a force that supports the pedal force and a counteracting force, other energy storage systems must be used to achieve a precisely defined force distribution. For example, so-called C-springs or star springs are used, which are, however, very expensive.

[0006] DE 10 2010 054 260 A1, for example, describes a device for reducing pedal force for clutch pedals, which provides an alternative form of clutch assistance compared to the use of over-center springs. A sleeve is mounted around the rotational axis of a clutch pedal, in which spring means (e.g., a star-shaped spring element) are accommodated. Furthermore, a rolling element is mounted within the sleeve in such a way that when the clutch pedal moves around the rotational axis, the rolling element is carried along in a rolling movement along a predetermined path. The rotational movement of the pedal is thus converted into a spring deflection, which does not result in a dead center. The disadvantages of the use of over-center springs described above can thus be avoided. However, this device has a complex and expensive design.

[0007] In automotive engineering, so-called clutch-by-wire systems are known as automatic clutch actuations. In a clutch-by-wire system, the actuation of the clutch, i.e. the opening and closing of the clutch, is not carried out directly by the driver of the vehicle by actuating the clutch pedal. Instead, the actuation of the clutch pedal is detected, for example, by a clutch pedal sensor and evaluated by a control unit, which then, depending on other vehicle condition parameters, controls an actuator to open and close the clutch. This means that there is no longer a direct mechanical or hydraulic connection between the clutch pedal and the clutch release system. In these automated clutch systems, the clutch pedal is only intended to trigger the clutch actuation.The clutch pedal's actuation force is no longer dependent on the force required to disengage the clutch. However, it has been shown that it is advantageous for the driver if they still have to apply a certain actuation force to actuate the clutch, as is also necessary with conventional clutch systems. An arrangement according to the preamble of claim 1 is disclosed in DE 195 06 592 A1. Further prior art is described in EP 1 903 235 A2.

[0008] The object of the invention is to develop an arrangement for actuating vehicle clutches which represents a cost-effective solution for storing force on the clutch pedal, whereby any desired clutch characteristics can be mapped.

[0009] The problem is solved by the features of the first patent claim. Advantageous embodiments of the invention are listed in the subclaims.

[0010] In an arrangement for actuating a vehicle clutch, in which the movement of a pedal pivotably mounted about an axis of a pedal bracket is transmitted to a kinematic system having at least one energy storage device, by means of which an actuating force to be applied to the pedal can be influenced, the kinematic system according to the invention comprises a gear transmission operatively connected to the pedal, which is formed from non-circular gears / gear segments. The gears / gear segments are preloaded by the energy storage device designed as a spring element.

[0011] According to the invention, the gears / gear segments are arranged at least partially on the pedal, with at least two meshing gears / gear segments being provided, one gear / gear segment being fixed and the other gear / gear segment being rotatable. Depending on the pivoting movement of the pedal about its axis, a forced rotational movement of the gear / gear segment about a rotational axis takes place.

[0012] Advantageously, the spring element, designed as a helical spring, is attached on one side to a component fixed to the housing / body, and on the other side, is hinged to the rotatable gear / gear segment by an end piece. Depending on the arrangement of the spring element on the component fixed to the housing / body and / or the attachment to the rotatable gear / gear segment, a force can be achieved that supports or counteracts the actuating force applied to the pedal.

[0013] In a preferred embodiment, the spring element is designed as a leg spring, which is arranged on the axis of rotation of the rotatable gear / gear segment.

[0014] Advantageously, the gear / gear segment and / or the gear / gear segment can be arranged on the pedal and / or on the pedal bracket / on a component fixed to the housing. The gear transmission can be formed from more than two gears / gear segments.

[0015] The invention is explained in more detail below using exemplary embodiments and associated drawings.

[0016] They show in schematic representation: Fig. 1 shows a first embodiment of an arrangement for actuating a vehicle clutch, Fig. 2 shows a second embodiment of an arrangement for actuating a vehicle clutch, Fig. 3 shows a third embodiment of an arrangement for actuating a vehicle clutch, Fig. 4 a fourth embodiment of an arrangement for actuating a vehicle clutch.

[0017] In the Fig. Figures 1 to 4 show exemplary embodiments that can be used particularly for mechanical and electronic clutches (clutch-by-wire). However, they can also be used for other vehicle clutches.

[0018] This shows Fig. 1 shows a schematic representation of an inventive embodiment of an arrangement for actuating clutches in motor vehicles, comprising a clutch pedal 1 mounted on a housing component, for example, a pedal bracket, such that it can pivot about an axis A. Typically, the pedal 1 has a tread 2 that the driver touches with their foot when engaging or disengaging the clutch, causing the pedal 1 to perform a pivoting movement s about the axis A. The further actuators for actuating the clutch will not be discussed in detail here, as they are not relevant to the invention.

[0019] An energy storage device 3 formed by a spring element is fixed to the housing, for example, on a body K (only indicated here) of the vehicle. The preloaded spring element 3, preferably a helical spring, is hinged at one end 3.1 to a non-circular gear 4. The teeth of the rotatably movable gear 4 mesh with the teeth of a fixed, likewise non-circular, gear 5. The gear transmission formed by the two gears 4, 5 and preloaded by the spring element 3 is operatively connected to the pedal 1.

[0020] In Fig. 1 shows two non-circular gears 4, 5 meshing with each other. Depending on the desired / required clutch characteristic, more than two gears 4, 5 can be used, which are preloaded by means of the energy storage / spring element 3. The gears 4, 5 can advantageously be designed as gear segments, as shown in the Fig. 2 to 4. In this way, material, manufacturing, and cost expenditure, as well as space requirements, are reduced while maintaining functionality.

[0021] Various arrangement / attachment variants of the gears 4, 5 are possible to achieve the desired coupling characteristic. The arrangements shown in the drawings Fig. 1 to Fig. The arrangements shown in Figure 4 are to be regarded only as a selection of exemplary embodiments.

[0022] One variant provides for the attachment of the fixed gear 5 to the pedal 1. The teeth of the gear 5 engage with the teeth of the rotatable gear 4, which is not connected to the pedal 1 here and is preloaded via the spring element 3. When an actuating force is applied to the pedal 1 - for example, by the driver's foot on the tread 2 - the pedal 1 performs a pivoting movement s about the axis A. This movement is also performed by the gear 5, which is firmly connected to the pedal 1, causing a rotary movement of the gear 4 about its axis of rotation A1 via the engaged teeth. This results in a displacement of the end 3.1 of the spring element 3 hinged to the gear 4, which leads to a relief or loading of the spring element 3.

[0023] An arrangement of both gears 4, 5 on the pedal 1 is also conceivable, with the gear 5 again being connected to the pedal 1 in a rotationally fixed manner. The gear 4 is mounted on the pedal 1 so that it can rotate about its axis of rotation A1. The spring element 3 hinged to the gear 4 preloads the gears 4, 5, which mesh with each other via their teeth,. Analogous to the variant described above, during a pivoting movement s of the pedal 1, the fixed gear 5 is also moved, whereby the rotatable gear 4 executes a rotational movement about its axis of rotation A1 and thus causes a change in the state of the spring element 3.

[0024] In another variant, the fixed gear 5 is arranged outside the pedal 1, for example on the pedal bracket, and the rotatable gear 4 is arranged on the pedal 1. Here, too, the rotatable gear 4, preloaded via the spring element 3, engages with the gear 5. During a pivoting movement s of the pedal 1 about the axis A, the teeth of the rotatable gear 4 mesh with the teeth of the fixed gear 5, causing a displacement of the end 3.1 of the spring element 3 and thus its loading or unloading.

[0025] Depending on the requirements and complexity of the desired clutch characteristic, the arrangement according to the invention can be varied as desired and expanded with additional gears.

[0026] What all embodiments have in common is their mode of operation, in which the pivoting movement s of the pedal 1, due to the meshing teeth of the two non-circular gears 4, 5 and the resulting rotational movement of the gear 4, leads to a relief or a load on the spring element 3. This occurs depending on the direction of the pivoting movement s of the pedal 1. Likewise, the arrangement of the spring element 3 on the body or its specific articulation on the gear 4 is responsible for whether the spring element 3 is relieved or further loaded when the clutch is opened, and whether a force is generated that supports or counteracts the actuating force to be applied to the pedal 1.

[0027] Due to the non-circular design of gears 4 and 5, all designs / arrangements result in a non-linear rolling speed, which in turn allows for the generation of a non-linear force. The resulting pedal force-pedal travel characteristic curve exhibits a correspondingly complex profile.

[0028] Depending on the field of application, the arrangement according to the invention can be used to generate a force that supports the pedal force / actuating force or to generate a force that counteracts the pedal force / actuating force.

[0029] This shows Fig. 2 shows an embodiment of an arrangement for actuating a clutch according to the invention, which is provided in particular for pedal force assistance, for example in a mechanical clutch actuating device. The gears 4, 5, designed here as gear segments 4 and 5, respectively, are analogous Fig. 1, wherein the gear segment 5 is stationary and engages with the gear segment 4, which can pivot about the rotation axis A1. The gear segments 4, 5 are preloaded via the spring element 3, which is connected to the gear segment 4 and is designed, for example, as a helical compression spring. The spring element 3 is arranged on a component fixed to the housing, e.g., on the body K, in such a way that when the pedal 1 is actuated to open the clutch and the resulting rotational movement of the rotatable gear segment 4, the spring element 3 has a pedal force-assisting effect. The pedal force / actuating force that must be applied to the pedal 1 is thus reduced.

[0030] In Fig. Figure 3 shows an embodiment of an arrangement for actuating a clutch according to the invention, particularly suitable for use in a clutch-by-wire system. The gear segments 4, 5 are analogous to the gear segments 4, 5 of Fig. 2. However, here the spring element 3 is attached to the body K in such a way that when the pedal 1 is acted upon in the direction of opening the clutch, a counterforce is generated via the spring element 3, which means an increase in the actuating force to be applied to the pedal 1.

[0031] In Fig. Figure 4 shows a further embodiment of an arrangement for actuating a clutch according to the invention. A leg spring is used as the spring element 3, which is arranged on the rotational axis A1 of the rotatable gear segment 4. One leg 3.2 is fixedly arranged, while another leg 3.3 is connected to the gear segment 4. Upon a pivoting movement s of the pedal 1 about the axis A and a corresponding rotational movement of the gear segment 4 about the rotational axis A1, the leg spring 3 is either relaxed or loaded, depending on the initial position of the leg 3.3.

[0032] The use of non-circular gears / gear segments 4, 5, which are preloaded by a spring element 3, generates a non-linear rolling speed and thus a non-linear force. Any desired clutch characteristic curve can be achieved by arranging the spring element 3 and / or the gears / gear segments 4, 5 in various configurations. Non-circular gears are increasingly being used in many areas of technology. They can be optimally designed for specific transmission tasks and can also be manufactured cost-effectively with high quality. The gears / gear segments 4, 5 are preferably made of plastic. List of reference symbols 1 pedal / clutch pedal 2 tread 3 Energy storage / spring element / coil spring / leg spring 3.1 End / end piece of the spring element 3.2 Leg of the torsion spring 3.3 Leg of the torsion spring 4 rotating gear / gear segment 5 fixed gear / gear segment A axis of the pedal A1 Axis of rotation of the gear / gear segment K Body / housing-fixed component s Pivoting movement of the pedal

Claims

[1] Arrangement for actuating a vehicle clutch, in which a movement of a pedal (1) pivotably mounted about an axis (A) of a pedal block is transferable to a kinematics having at least one energy storage device (3), by means of which an actuating force to be applied to the pedal (1) can be influenced, characterized by that the kinematics comprises a gear transmission which is operatively connected to the pedal (1) and which is formed from non-circular gears / gear segments (4, 5), characterized by that the gears / gear segments (4, 5) are at least partially arranged on the pedal (1). [2] Arrangement according to claim 1, characterized by that the gears / gear segments (4, 5) are preloaded by the energy accumulator (3) designed as a spring element (3). [3] Arrangement according to one of claims 1 to 2, characterized bythat at least two gearwheels / gearwheel segments (4, 5) are provided which mesh with one another, one gearwheel / gearwheel segment (5) being fixed and the other gearwheel / gearwheel segment (4) being rotatable. [4] Arrangement according to claim 3, characterized by that depending on the movement of the pedal (1) about the axis (A), a forced rotational movement of the gear / gear segment (4) about a rotational axis (A1) takes place. [5] Arrangement according to one of claims 2 to 4, characterized by that the spring element (3) designed as a helical spring (3) is fastened on the one hand to a component fixed to the housing / to a body (K) and on the other hand is articulated to the rotatable gear / gear segment (4). [6] Arrangement according to claim 5, characterized bythat depending on the arrangement of the spring element (3) on the housing-fixed component / body (K) and / or on the fastening to the rotatable gear / gear segment (4), a force can be achieved which supports the actuating force to be applied to the pedal (1) or which counteracts the actuating force. [7] Arrangement according to one of claims 2 to 4, characterized by that the spring element (3) is designed as a leg spring (3) which is arranged on the axis of rotation (A1) of the rotatable gear / gear segment (4). [8] Arrangement according to one of claims 1 to 7, characterized by that the fixed gear / gear segment (5) or the rotatable gear / gear segment (4) is arranged on the pedal (1) and the other gear / gear segment (4, 5) is arranged on the pedal bracket / on a component (K) fixed to the housing. [9] Arrangement according to one of claims 1 to 8, characterized bythat the gear transmission is formed from more than two gears / gear segments (4, 5).

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